Pliable proximity switch assembly and activation method.

(54) Title: FLEXIBLE ASSEMBLY OF PROXIMITY SWITCHES AND ACTIVATION METHOD.

(54) Title: PLIABLE PROXIMITY SWITCH ASSEMBLY AND ACTIVATION METHOD.

(57) Summary

A proximity switch assembly and a method of detecting activation of a proximity switch assembly is provided. The assembly includes a plurality of proximity switches, each having a proximity sensor that provides a sensing actuation field and control circuitry that processes the actuation field of each proximity switch to detect actuation. A flexible material overlaps the proximity sensors. The control circuits monitor the actuation field and determine an actuation of a proximity switch based on a signal generated by the sensor relative to a threshold when a user's finger presses on the flexible material. The flexible material may further include a raised portion and an air gap between the raised portion and the sensor.

(57) Abstract

A proximity switch assembly and method for detecting activation of a proximity switch assembly is provided. The assembly ineludes a plurality of proximity switches each having a proximity sensor providing a sense activation field and control circuitry Processing the activation field of each proximity switch to sense activation. A pliable material overlays the proximity sensors. The control circuitry monitors the activation field and determines an activation of a proximity switch based on a signal generated by the sensor in relation to a threshold when a user's finger depresses the pliable material. The pliable material may further inelude an elevated portion and an air gap between the elevated portion and the sensor.

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Institute

Mexican Property

Industrial □

PATENT TITLE NO. 347131

Headlines)

FORD GLOBAL TECHNOLOGIES. LLC

Home:

Denomination:

Fairlane Plaza South, Suite 800, 330 Town Center Drive, Dearbom, Michigan, 48126, USA

FLEXIBLE MOUNTING OF PROXIMITY SWITCHES AND ACTIVATION METHOD.

Classification:

Int CI.8: G01R27 / 26; H03K17 / 955

Inventories):

MAHENDRA SOMASARA DASSANAYAKE, STUART O. SALTER; JEFFREY SINGER; MICHAEL ISTOK; PIETRO BUTTOLO

REQUEST

Number:

MX / a / 2015/006232

Presentation facade:

Ηοπκ May 2015

14:27

PRIORITY

Country!

Date:

Number:

US May 2014

14/284,659

Validity: Twenty years

Expiration Date: May 18, 2035

The reference patent is granted based on articles 1, 2, section V. 6, section III, and 58 of the Industrial Property Law.

In accordance with article 23 of the Industrial Property Law, this patent is valid for twenty years, non-extendable, counted from the filing date of the application and will be subject to the payment of the fee to keep the rights in force.

Whoever signs this title does so based on the provisions of articles 6 ° fractions lll and 7 ° bis 2 of the Industrial Property Law (Official Gazette of the Federation (DOF) 06/27/1991, amended on 02 / 08/1994, 10/28/1996, 12/26/1997, 05/17/1999, 01/26/2004, 06/16/2005, 01/25/2006, 05/06/2009, 06/01 / 2010,1W06 / 2010, 28 / O8 / 2O10, 01/27/2012 and 04/09/2012); Articles 1® 3rd section V subsection a), 4 “and 12th sections I and III of the Regulation of the Mexican Institute of Industrial Property (DOF 12/14/1999, amended on 07/01/2002, 07/15/2004 , 07/28/2004 and 09/07/2007); Articles 1, 3, ¿5 · section V section e) 16 sections I and III and 30 of the Organic Statute of the Mexican Institute of Industrial Property (DOF 12/27/1999, amended on 10/10/2002, 07/29/2004, 08/04/2004 and 09/13/2007); 1st, 3rd and 5th subsections) of the Agreement that delegates to the General Directors Adiantos, CoordMMMeMMMMMMomMKTituiares of the Regional Offices, Divisional Deputy Directors, Departmental Coordinators and other subordinates of the Mexican Institute of Industrial Property. (DOF 12/15/1999, amended on 02/04/2000, 07/29/2004, 08/04/2004 and 09/13/2007).

Issue Date: April 17, 2017

THE DIVISIONAL DIRECTOR OF PATENTS

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NAHANNY CANAL REYES

XúLhS'íifc

cp iaj. y :. from Mexico

MX / 2017/31777

<img file="MX347131B_D0003.tif" />

FLEXIBLE MOUNTING OF PROXIMITY SWITCHES

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MEUCANO INSTITUTE

DBUnÑRCMB

INDUSTRIAL

AND ACTIVATION METHOD

FIELD OF THE INVENTION

The present invention relates generally to switches and more particularly relates to proximity switches having a higher determination of the actuation of the switches.

BACKGROUND OF THE INVENTION

Motor vehicles are typically equipped with various user-actuated switches, such as switches to operate devices, including actuated windows, headlights, windshield wipers, sunroofs or sunroofs, interior lighting, radio and infotainment devices, and various other devices. In general, these types of switches must be actuated by a user in order to activate or deactivate a device or perform some type of control function. Proximity switches, such as capacitive switches, employ one or more proximity sensors to generate a sensing actuation field and detect changes in the actuation field indicative of user actuation of the switch, typically caused by a finger of the operator. user in close proximity or contact with the sensor. Capacitive switches are typically configured to detect user actuation of the switch based on comparing the sensing actuation field to a threshold.

Switch assemblies frequently employ a plurality of capacitive switches in close proximity to each other and generally require a user to select a single desired capacitive switch to perform the desired operation. In some applications, such as use in an automobile, the driver of the vehicle has a limited ability to view the switches due to driver distraction. In such applications, it is desirable to allow the user to explore the switch mounting for a specific button while

<img file="MX347131B_D0004.tif" />

IMPI

INSTITUTO MEXICANO m the INDUSTRIAL nonuiAD that avoids at the same time a premature determination of the switch activation. Thus, it is desirable to discriminate whether the user intends to flip a switch or just scan for a specific switch button while concentrating on a higher priority task, such as driving, or does not intend to flip a switch. . Thus, it is desirable to provide a proximity switch arrangement that enhances the use of the proximity switches by a person, such as a driver of a vehicle.

BRIEF DESCRIPTION OF THE INVENTION

In accordance with one aspect of the present invention, a proximity switch assembly is provided. The proximity switch assembly includes a proximity sensor that generates an actuation field, a flexible material that lines the proximity sensor, and control circuitry that monitors the actuation field and determines an actuation of a proximity switch based on a signal generated by the sensor relative to a threshold when a user's finger presses on the flexible material.

In accordance with another aspect of the present invention, a method of activating a proximity switch is provided. The method includes the steps of generating a trigger field associated with a proximity sensor and monitoring a signal indicative of the trigger field. The method also includes the steps of determining an amplitude when the signal is stable for a minimum period of time and generating a trigger output when the amplitude exceeds a first amplitude by a known amount indicative of a user pressing on a flexible coating material. to the proximity sensor.

Those skilled in the art will understand and appreciate these and other aspects, objects and features of the present invention upon study of the following specification, claims, and accompanying drawings.

<img file="MX347131B_D0005.tif" />

IMPI

MEXICAN INSTITUTE

BE LA FMV1IBA * iNnumuAi

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a perspective view of a passenger compartment of a motor vehicle having a roof console employing a proximity switch assembly, in accordance with one embodiment;

FIG. 2 is an enlarged view of the overhead console and proximity switch assembly shown in FIG. 1;

FIG. 3 is an enlarged cross-sectional view taken along the line lilili in FIG. 2, showing a series of proximity switches in relation to a user's finger;

FIG. 4 is a schematic diagram of a capacitive sensor employed in each of the capacitive switches shown in FIG. 3;

FIG. 5 is a block diagram illustrating proximity switch mounting, in accordance with one embodiment;

FIG. 6 is a graph illustrating the signal count for a channel associated with a capacitive sensor showing an activation motion profile;

FIG. 7 is a graph illustrating the signal count for two channels associated with the capacitive sensors showing a scan / search slip motion profile;

FIG. 8 is a graph illustrating the signal count for a signal channel associated with capacitive sensors showing a slow-on motion profile;

FIG. 9 is a graph illustrating the signal count for two channels associated with the capacitive sensors showing a rapid scan / search slide motion profile;

FIG. 10 is a graph illustrating signal count for three channels associated with capacitive sensors in a scan / search mode illustrating stable pressure activation at the peak, in accordance with one embodiment;

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MEXICAN INSTITUTE

OF THE MDHEOAD

INDUSTRIAL

<img file="MX347131B_D0006.tif" />

FIG. 11 is a graph illustrating signal count for three channels associated with capacitive sensors in a scan / search mode illustrating stable pressure activation on signal descent below peak, in accordance with another embodiment;

FIG. 12 is a graph illustrating signal count for three channels associated with capacitive sensors in a scan / search mode illustrating increasing stable pressure on a pad to activate a switch, in accordance with a further embodiment;

FIG. 13 is a graph illustrating signal counting for three channels associated with capacitive sensors in a scan mode and selection of a pad based on a stable pressure rise, in accordance with a further embodiment;

FIG. 14 is a state diagram illustrating five states of capacitive switch assembly that is implemented with a state machine, in accordance with one embodiment;

FIG. 15 is a flow chart illustrating a routine for executing a method of activating a switch of the switch assembly, in accordance with one embodiment;

FIG. 16 is a flow chart illustrating the processing of switch activation and switch release;

FIG. 17 is a flow chart illustrating the logic for switching between switch null and switch active states;

FIG. 18 is a flow chart illustrating the logic for switching from switch active state to switch null or switch threshold state;

FIG. 19 is a flow chart illustrating a routine for switching between switch threshold and switch search states;

FIG. 20 is a flow chart illustrating a virtual button method that implements the search state of the switch;

<img file="MX347131B_D0007.tif" />

FIG. 21 is a graph illustrating the signal count for a channel associated with a capacitive sensor having a scan mode and a virtual button mode for activating a switch, in accordance with a further embodiment;

IMPI

INSTtTUT · MUICAN · H LA FSOHSDAO INDUSTRIAL

FIG. 22 is a graph illustrating the signal count for the virtual button mode in which an activation is not triggered;

FIG. 23 is a graph illustrating the signal count for the capacitive sensor in the scan mode further illustrating when the switch is activated, according to the embodiment of FIG. twenty-one;

FIG. 24 is a graph illustrating the signal count for a capacitive sensor that further illustrates when triggers are actuated, in accordance with the embodiment of FIG. twenty-one;

FIG. 25 is a graph illustrating the signal count for a capacitive sensor further illustrating a wait time to exit virtual button mode and re-enter virtual button mode, in accordance with the embodiment of FIG. twenty-one;

FIG. 26 is a flow chart illustrating a routine for processing the signal channel with a virtual button mode, in accordance with the embodiment shown in FIG. twenty-one;

FIG. 27 is a flow chart illustrating a virtual button method for processing! signal channel, according to the embodiment of FIG. twenty-one;

FIG. 28A is a cross-sectional view of a proximity switch assembly with proximity switches and a flexible coating material relative to a user's finger shown in a first position, in accordance with another embodiment;

FIG. 28B is a cross-sectional view of the proximity switch assembly of FIG. 28A further illustrating the user's finger in a second position;

<img file="MX347131B_D0008.tif" />

IMPI injthvt · Mexican

M LA PWRKDAD iNWJynUAL

FIG. 28C is a cross-sectional view of the proximity switch assembly of FIG. 28A further illustrating finger tightness on the flexible layer in a third position;

FIG. 28D is a graph illustrating the signal generated by one of the proximity sensors in response to finger movement and squeezing of the flexible cover as shown in FIGS. 28A-28C;

FIG. 29A is a cross-sectional view of a proximity switch assembly employing a flexible cover material having raised regions with air gaps and a user's finger shown in a first position, in accordance with a further embodiment;

FIG. 29B is a cross-sectional view of the proximity switch assembly of FIG. 29A further illustrating the user's finger in a second position;

FIG. 29C is a cross-sectional view of the proximity switch assembly as shown in FIG. 29A further illustrating depressing the switch by a user's finger in a third position;

FIG. 29D is a graph illustrating a signal generated by one of the sensors in response to finger movement as shown in FIGS. 29A29C;

FIG. 30 is a state diagram illustrating various states of the capacitive switch assembly having the flexible covering material and a virtual button mode; and

FIG. 31 is a flow chart illustrating a routine for processing the signal generated with a proximity switch having a flexible material cover, in accordance with one embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As required, detailed embodiments of the present invention are described herein; however, it should be understood that the described embodiments are merely exemplary of the invention that can be carried out in various alternative ways. Figures are not necessarily in a detailed design; some schematics may be exaggerated or minimized to show a summary of functions. Therefore, the specific structural and functional details described herein are not to be construed as limiting, but merely as a representative basis for teaching a person skilled in the art to variously employ the present invention.

With reference to FIGS. 1 and 2, the interior of a motor vehicle 10 is generally illustrated with a passenger compartment and a switch assembly 20 employing a plurality of proximity switches 22 having switch activation monitoring and determination, in accordance with one embodiment . The vehicle 10 generally includes a roof console 12 mounted to the headliner trim at the bottom of the roof or the deck at the top of the vehicle's passenger compartment, generally above the front passenger seating area. . The switch assembly 20 has a plurality of proximity switches 22 arranged close to each other on the roof console 12, in accordance with one embodiment. The various proximity switches 22 can control any of a number of vehicle devices and functions, such as controlling the movement of a sunroof or sunroof 16, controlling the movement of a sunroof louver 18, controlling the activation of one or more lighting devices such as the interior map / reading and zenith lights 30, and various other devices and functions. However, it should be appreciated that the proximity switches 22 may be located elsewhere on the vehicle 10, such as on the instrument panel, on other consoles such as a center console, integrated into a touch screen display 14 for a system. radio or infotainment devices, such as a navigation screen and / or audio display, or located elsewhere on board vehicle 10 in accordance with various vehicle applications.

Proximity switches 22 are shown and described herein as capacitive switches, in accordance with one embodiment. Each proximity switch 22 includes at least one proximity sensor that provides a sensing trigger field to detect a contact or close proximity (eg, within one millimeter) of a user relative to the one or more sensors. proximity, such as a sliding motion by a user's finger. Therefore, the sensing drive field of each proximity switch 22 is a capacitive field in the exemplary embodiment, and the user's finger has electrical conductivity and dielectric properties that cause a change or disturbance in the drive field. detection as should be apparent to those skilled in the art. However, those skilled in the art should also appreciate that additional or alternative types of proximity sensors may be used, such as, but not limited to, inductive sensors, optical sensors, temperature sensors, resistive sensors, or the like or a combination. thereof. Exemplary proximity sensors are described in the Atmel® Touch Sensor Design Guide of April 9, 2009, 10620 D-AT42-04 / 09, the full reference of which is hereby incorporated herein by reference.

Each of the proximity switches 22 shown in FIGS. 1 and 2 provide control of a vehicle component or device or provide a specific control function. One or more of the proximity switches 22 may be designed to control the movement of a sunroof or sunroof 16 in such a way as to cause the sunroof 16 to move in an open or closed direction, tilt the sunroof, or stop the sunroof. moonroof movement based on a control algorithm. One or more other proximity switches 22 may be designed to control the movement of a sunroof louver 18 between the open and closed positions. Each of the sunroof 16 and louver 18 can be driven by an electric motor in response to the

<img file="MX347131B_D0009.tif" />

IMPI

MWUCANO INSTITUTE

Dt LA IWÍMkPAl

INDUÍnUAL actuation of the corresponding proximity switch 22. Other proximity switches 22 can be used to control other devices, such as turning on an interior map / reading light 30, turning off an interior map / reading light

30, turn an overhead light on or off, unlock a trunk, open a rear hatch, or override a door light switch. Additional controls via the proximity switches 22 may include operating the door windows up and down. Various other vehicle controls can be controlled by means of proximity switches 22 described herein.

With reference to FIG. 3, a portion of the proximity switch assembly 20 is illustrated with a series of three proximity switches 22 arranged in series in close relationship with each other relative to a user's finger 34 during use of the switch assembly 20. Each switch Proximity sensor 22 includes one or more proximity sensors 24 to generate a detection trigger field. According to one embodiment, each of the proximity sensors 24 can be formed by conductive printing ink on the upper surface of the polymeric ceiling console 12. An example of a printing ink proximity sensor 24 is shown in FIG. . 4 generally with an excitation electrode 26 and a receiving electrode 28 where each has interdigitated fingers to generate a capacitive field 32. It should be appreciated that each of the proximity sensors 24 may be formed in another manner such as by mounting a preformed conductor circuit track on a substrate in accordance with other embodiments. The drive electrode 26 receives square wave drive pulses applied to the voltage Vi. The receiving electrode 28 has an output to generate an output voltage Vo. It should be appreciated that the electrodes 26 and 28 can be arranged in various other configurations to generate the capacitive field as the drive field 32.

In the embodiment shown and described herein, the drive electrode 26 of each proximity sensor 24 is applied with voltage input Vi as square wave pulses having a charge pulse cycle sufficient to charge the

<img file="MX347131B_D0010.tif" />

IMPI

INSTITUTE MUICANe

M LA WOMElUD * numiui receiving electrode 28 at a desired voltage. The receiving electrode 28 thus acts as a measurement electrode. In the embodiment shown, the adjacent detection trigger fields 32 generated by the adjacent proximity switches 22 overlap slightly, however, there may be no overlap according to other embodiments. When a user or operator, such as the user's finger 34, enters a trigger field 32, the proximity switch assembly 20 detects the disturbance caused by the finger 34 to the trigger field 32 and determines whether the disturbance is sufficient as to activate the corresponding proximity switch 22. Trigger field disturbance 32 is detected by processing the load pulse signal associated with the corresponding signal channel. When the user's finger 34 contacts two trigger fields 32, the proximity switch assembly 20 detects the disturbance of the two contacted trigger fields 32 via separate signal channels. Each proximity switch 22 has its own determined signal channel that generates the load pulse count that is processed as described herein.

With reference to FIG. 5, the proximity switch assembly 20 is illustrated in accordance with one embodiment. A plurality of proximity sensors 24 are shown providing inputs to a controller 40, such as a microcontroller. Controller 40 can include control circuitry, such as a microprocessor 42 and memory 48. The control circuit may include sensing control circuits that process the trigger field of each sensor 22 to detect activation of the corresponding switch by the user by comparing the trigger field signal with one or more thresholds in accordance with one or more more control routines. It should be appreciated that other analog and / or digital control circuits may be employed to process each trigger field, determine user trigger, and initiate action. Controller 40 may employ a QMatrix acquisition method available from ATMEL®, in accordance with one embodiment. The ATMEL acquisition method uses a WINDOWS® C / C ++ host compiler and a WinAVR debugger to simplify development and

<img file="MX347131B_D0011.tif" />

IMPI

INSTTTUTO MEXICANA DE LA PROHIBA »INBUÍTRLAL test of the Hawkeye utility that allows real-time monitoring of the internal status of critical variables in the software, as well as the collection of data records for further processing.

Controller 40 provides an output signal to one or more devices that are configured to perform certain actions in response to successful activation of a proximity switch. For example, the one or more devices may include a sunroof 16 having a motor to move the sunroof panel between the open and closed and tilt positions, a sunroof louver 18 that moves between the open and closed positions. , and lighting devices 30 that can be turned on and off. Other devices such as a radio can be controlled to perform on / off functions, volume control, scan, and other types of devices to perform certain other functions. One of the proximity switches 22 can be used to actuate the sunroof closed, another proximity switch 22 can be destined to actuate the sunroof open and an additional switch 22 can be destined to actuate the sunroof to a tilt position, all of them could have a motor move the sunroof to the desired position. The sunroof louver 18 may open in response to one proximity switch 22 and may close in response to another proximity switch 22.

Controller 40 is further shown with an analog-to-digital (A / D) comparator 44 coupled to microprocessor 42. A / D comparator 44 receives the voltage output Vo from each of the proximity switches 22, converts the analog signal into a digital signal and provides the digital signal to microprocessor 42. In addition, controller 40 includes a pulse counter 46 coupled to microprocessor 42. The pulse counter 46 counts the charge signal pulses that are applied to each excitation electrode of each proximity sensor, counts the pulses required to charge the capacitor until the voltage output Vo reaches a predetermined voltage, and provides the count to microprocessor 42. The pulse counter is indicative of the change in

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<img file="MX347131B_D0012.tif" />

capacitance of the corresponding capacitive sensor. Controller 40 is further shown in communication with a pulse width modulated drive buffer.

fifteen. Controller 40 provides a pulse width modulated signal to pulse width modulated drive buffer 15 to generate a train of square wave pulses Vi that is applied to each drive electrode of each proximity sensor / switch 22. The controller 40 processes a control routine 100 stored in memory to control and make a determination as to the activation of one of the proximity switches.

In FIGS. 6-13, the change in the sensor load pulse count shown as the signal count Δ for a plurality of signal channels associated with a plurality of proximity switches 22, such as the three switches 22 shown in FIG. 3, is illustrated according to various examples. The change in sensor load pulse count is the difference between an initialized reference count value with no finger or other object present in the trigger field and the corresponding sensor reading. In these examples, the user's finger enters activation fields 32 associated with each of three proximity switches 22, generally one sensing activation field at a time with overlap between adjacent activation fields 32 when the user's finger user moves through the series of switches. Channel 1 is the change (Δ) in sensor load pulse count associated with a first capacitive sensor 24, channel 2 is the change in sensor load pulse count associated with the second adjacent capacitive sensor 24, and Channel 3 is the change in sensor load pulse count associated with the third capacitive sensor 24 adjacent to the second capacitive sensor. In the described embodiment, the proximity sensors 24 are capacitive sensors. When a user's finger is in contact or in close proximity to a sensor 24, the finger alters the capacitance measured at the corresponding sensor 24. The capacitance is parallel to the parasitic capacitance of the untouched sensor pad, and as such , is measured as an offset. The induced capacitance of the user or operator is proportional to the dielectric constant of the finger or other part of the user's body, the

<img file="MX347131B_D0013.tif" />

IMPI

MEXICAN INSTITUTE

OE THE INDUSTRIAL RROWSTY surface exposed to the capacitive pad, and is inversely proportional to the distance from the user's limb to the switch button. According to one embodiment, each sensor is excited with a train of voltage pulses through pulse width modulation (PWM) electronics until the sensor is charged to a specified voltage potential. Such an acquisition method charges the receiving electrode 28 to a known voltage potential. The cycle repeats until the voltage across the measuring capacitor reaches a predetermined voltage. Placing a user's finger on the touch surface of switch 24 introduces external capacitance that increases the amount of charge transferred in each cycle, thereby reducing the total number of cycles required for the measurement capacitance to reach the minimum. default voltage. The user's finger causes the change in the sensor charge pulse count to increase as this value is based on the initialized reference count minus the sensor reading.

The proximity switch assembly 20 is capable of recognizing the movement of the user's hand when the hand, particularly a finger, is in close proximity to the proximity switches 22, to discriminate whether the intention of the user is to activate a switch 22 , scan for a specific button while focusing on higher priority tasks such as driving, or is the result of a task such as adjusting the rear view mirror that has nothing to do with actuation of a proximity switch 22. The proximity switch assembly 20 can operate in a scan or search mode that allows the user to scan keyboards or buttons by swiping or sliding a finger in close proximity to switches without triggering a switch activation until user intent is determined. The proximity switch assembly 20 monitors the amplitude of a generated signal in response to the trigger field, determines a differential change in the generated signal, and generates a trigger output when the differential signal exceeds a threshold. As a result, exploration of the proximity switch assembly 20 is allowed, such that users are free to explore the pad.

<img file="MX347131B_D0014.tif" />

IMPI

INSTITUTE MiXJCAN ·

BE U MU * IEOA »fNnumuAi switch interface with your fingers without unintentionally activating an episode, the interface response time is fast, the activation occurs when'Tosciedo's contact a surface panel and inadvertent activation of the panel is avoided or reduced. switch.

With reference to FIG. 6, when user finger 34 approaches a switch 22 associated with signal channel 1, finger 34 enters activation field 32 associated with sensor 24 causing capacitance interruption, resulting in This way results in increased sensor count as shown by signal 50A having a typical trigger motion profile. An entry ramp slope method can be used to determine if the operator intends to press a button or scan the interface based on the entry ramp slope on the 50A signal of the channel 1 signal rising from the point 52 where signal 50A crosses the active level count (LVL_ACTIVE) to point 54 where signal 50A crosses the threshold level count (LVL_THRESHOLD), according to one embodiment. The slope of the input ramp is the differential change in the signal generated between points 52 and 54 that occurs during the time period between times tth and tac. Because the threshold level numerator - active level usually changes only when the presence of gloves is detected, but is otherwise a constant, the slope can be calculated just when the time to cross from the active level to the level expires. threshold referred to as tact¡ve2threshoid which is the difference between time tth and tac. A direct push on a switch pad can typically occur in a period of time referred to as tdirectpush in the range of about 40 to 60 milliseconds. If the tact¡ve2threshoid time is less than or equal to the direct push time tdirectpush, then it is determined that the switch activation has occurred. Otherwise, the switch is determined to be in a scan mode.

According to another embodiment, the slope of the input ramp can be calculated as the difference in time from time tac at point 52 with time t_Pk to reach the peak count value at point 56, referred to as the tact¡ve2peak time.

The tact¡ve2peak time can be compared to a direct push peak, referred to as td¡rect_push_pk which can have a value of 100 milliseconds according to one embodiment. If the tact¡ve2peak time is less than or equal to td¡rect_push_pk, it is determined that the activation of the switch has occurred. Otherwise, the switch assembly operates in a scan mode.

In the example shown in FIG. 6 shows the channel 1 signal rising as the capacitance disturbance increases rapidly rising from point 52 to the peak value at point 56. The proximity switch assembly 20 determines that the slope of the entry ramp is either the tact¡ve2threshoid or tact¡ve2peak time period for the signal to rise from the first threshold point 52 to either the second threshold at the point 54 or the peak threshold at point 56. The slope or differential change in the generated signal is then used for comparison to a representative forward thrust threshold td¡rect_push or td¡rect_push_pk to determine activation of the proximity switch. Specifically, when the tact¡ve2peak time is less than tdírect_push or tact¡ve2threshoid is less than td¡rect_push, the activation of the switch is determined. Otherwise, the switch assembly remains in scan mode.

With reference to FIG. 7, an example of a swipe / scan motion through two switches is illustrated when the finger passes or slides through the trigger field of two adjacent proximity sensors shown as channel 1 of the signal labeled 50A and Channel 2 of the signal labeled 50B. As the user's finger approaches a first switch, the finger enters the trigger field associated with the switch's first sensor causing the change in sensor count at signal 50A to increase at a slower rate so such that a reduced differential change in the generated signal is determined. In this example, the channel 1 profile of the signal experiences a change in the tactive time2_Peak that is not less than or equal to td¡rect_push, thereby resulting in entering search or browse mode. Because the tact¡ve2threshoid is indicative of a slow differential change in the generated signal, the activation of the switch button is not initiated, according

IMPI

<img file="MX347131B_D0015.tif" />

with a realization. According to another embodiment, because the tact¡ve2peak time is not less than or equal to td¡rect_push_pk, indicative of a slow differential change in a generated signal, the activation is not initiated, according to another embodiment. The second channel of the signal labeled 50B is displayed by becoming the maximum signal in the

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INTMimUAt transition point 58 and has an increase change in sensor count Δ with a differential change in signal similar to that of signal 50A. As a result, the first and second channels 50A and 50B reflect a sliding movement of the finger across two capacitive sensors in scan mode that results in the lack of activation of either switch. Using the tact¡ve2threshoid or tact¡ve2peak time period, a decision can be made whether or not to activate a proximity switch when its capacitance level reaches the peak of the signal.

For a slow forward push motion as shown in FIG. 8, additional processing may be employed to ensure that an activation is not intended. As shown in FIG. 8, Channel 1 of the signal identified as signal 50A is displayed in slowest rise during either tact¡ve2threshoid or tact¡ve2 time periods_Peak that would result in entering explore mode. When such a slip / scan condition is detected, with time tact¡ve2threshoid greater than td¡rect_push if the channel that does not meet the condition is the first channel of the signal to enter scan mode and is still the channel maximum (the channel with the highest intensity) when its capacitance falls below LVL_KEYUP_Threshold at point 60, then activation of the switch starts.

With reference to FIG. 9, a quick movement of a user's finger across the proximity switch assembly is illustrated without activation of the switches. In this example, the relatively large differential change in the signal generated for channels 1 and 2 is detected, for both channels 1 and 2 which are shown by lines 50A and 50B, respectively. The switch assembly uses a delayed time period to delay the activation of a decision until the transition point 58 at which the second signal channel 50B rises above the first signal channel 50A. The time delay can be

LM.PI nrcrnUT · MEXICAN

OF THE MIDDLE

INDUSTRIAL

<img file="MX347131B_D0016.tif" />

set equal to the time threshold td¡rect_push_pk according to one embodiment. Thus, by using a time delay period before determining the activation of a switch, very fast scanning of the proximity keypads prevents unintentional activation of a switch. Introducing the time delay time into the response can make the interface less sensitive and can function better when the operator's finger movement is substantially uniform.

If a previous threshold event that does not result in activation is recently detected, the scan mode can be entered automatically, according to one embodiment. As a result, once inadvertent actuation is detected and rejected, more caution may be applied for a period of time in scan mode.

Another way to allow an operator to enter scan mode is to use one or more appropriately marked and / or textured areas or pads on the surface of the switch panel associated with the proximity switches determined with the function of signaling. when mounting proximity switches the operator's intention to scan blindly. The one or more pads involved in the scan can be located in an easily accessible location that may not generate activity with other signal channels. According to another embodiment, a larger, unmarked scan-involved pad may be employed surrounding the entire switch interface. You will likely come across such a scan pad first when the operator's hand slides through the trim on the overhead console in search of a reference point from which to begin blind scanning of the proximity switch assembly.

Once the proximity sensor assembly determines whether an increase in the sensor count change is a switch activation or the result of a scan movement, the assembly proceeds to determine whether and how the scan movement should end in an activation of the proximity switch. According to one embodiment, the proximity switch assembly seeks

<img file="MX347131B_D0017.tif" />

a steady press on a switch button for at least a predetermined amount of time. In a specific embodiment, the predetermined amount of time is equal to or greater than 50 milliseconds, and more preferably

IMPI

INSTITUTO MEXICANO DE LA MIOHSBA »iNousruAi approximately 80 milliseconds. In FIGS. 10-13 illustrate examples of switch mounting operation using a time stable methodology.

With reference to FIG. 10, the scan of three proximity switches corresponding to signal channels 1-3 labeled 50A-50C signals, respectively, is illustrated while a finger slides across the first and second switches in scan mode and then activates the third switch associated with signal channel 3. When the finger scans the first and second switches associated with channels 1 and 2, no activation is determined because there is no stable signal on lines 50A and 50B. The signal on line 50A for channel 1 starts as the maximum signal value until channel 2 on line 50B becomes the maximum value and finally channel 3 becomes a maximum value. Signal channel 3 is displayed with a stable change in the sensor count near the peak value for a sufficient period of time tstabie, such as 80 milliseconds, which is sufficient to initiate activation of the corresponding proximity switch. When the threshold level trigger condition is met and a peak is reached, the stable level method activates the switch after the level at the switch is tied in a narrow range for at least the time period tstabie. This allows the operator to scan the various proximity switches and activate a desired switch once it is found by holding the user's finger position in the proximity of the switch for a stable period of time tstabie.

With reference to FIG. 11, another embodiment of the stable level method is illustrated in which the third signal channel on line 50C has a sensor count change having a stable condition on signal descent. In this example, the change in sensor count for the third channel exceeds the threshold

<img file="MX347131B_D0018.tif" />

level and has a stable pressure detected during the time period tstabie such that the activation of the third switch is determined.

According to another embodiment, the proximity switch mounting

IMPI

INSTITUI® MMICANL M INDUSTRIAL NONITY may employ a virtual button method that looks for an initial peak value of change in sensor count while in scan mode followed by a further sustained increase in change in sensor count to make the determination to activate the switch, as shown in FIGS. 12 and 13. In FIG. 12, the third signal channel on line 50C is raised to an initial peak value and then further increased by a change in the sensor count Cvb. This is equivalent to a user's finger gently brushing the surface of the switch mount as it slides through the switch mount, reaching the desired button and then pressing the virtual mechanical switch in such a way that the user's finger presses on the surface. contact of the switch and increase the amount of finger volume closer to the switch. The increase in capacitance is caused by the increase in the surface of the fingertip when it is compressed on the surface of the pad. The increase in capacitance can occur immediately after the detection of a peak value shown in FIG. 12 or it may occur after a decrease in the change in sensor count as shown in FIG. 13. The proximity switch assembly detects an initial peak value after another change increase in the sensor count indicated by the capacitance Cvb at a stable level or a stable period of time tstabie. A stable level of detection generally means that there is no change in noise absent from the sensor count value or a small change in noise absent from the sensor count value that can be predetermined during calibration.

It should be appreciated that a shorter period of time tstabie can lead to accidental activations, especially after a change in the direction of finger movement and that a longer period of time tstabie can lead to a less responsive interface.

iNSTiruT »Mexican

DE LA HIOFUUAD in »ustwal

It should also be appreciated that both the stable value method and the virtual button method can be active at the same time. By doing so, the stable time tstabie can be relaxed to be longer, such as one second, since the operator can always activate the button using the virtual button method without waiting for the stable pressure timeout.

Proximity switch mounting can further employ robust noise rejection to avoid nuisance inadvertent actuation. For example, with a roof console, accidental opening and closing of the sunroof should be avoided. Excessive noise rejection can reject intentional triggers, which should be avoided. One method of rejecting noise is to observe whether multiple adjacent channels are reporting simultaneous activation episodes, and in that case, select the signal channel with the highest signal and activate it, thereby ignoring all other signal channels until the release of the signal. selected signal channel.

The proximity switch assembly 20 may include a noise rejection signature method based on two parameters, namely a signature parameter which is the ratio of the channel between the highest intensity (max channel) and the overall level. accumulated (sum_channel), and the dac parameter which is the number of channels that are at least a certain relation of the max_channel. In one embodiment, the dac a0.5. The signature parameter can be defined by the following equation:

. . max channel max, __{0 n}charmel, signature = - = ----- = —-----^L.

sumchannel ^ channel, i = 0, n

The dac parameter can be defined by the following equation: dac = VchannelSj&gt; a_dac max_channel.

According to the dac, for a recognized trigger that must not be rejected, the channel must be generally clean, that is, the signature must be greater than a predefined threshold. In one embodiment, "^{dac = 1} = 0.4, and ^to^^and=² = 0.67. If the dac is greater than 2, the activation is rejected according to one embodiment.

<img file="MX347131B_D0019.tif" />

IMPI fNsrmrro mxcano

OE LA FROniDA »fNCMJSTUAL

When a decision is made whether or not to activate a switch in the downstream phase of the profile, then instead of max_channei and sum_cnannel, its peak values ​​peak_max_channel and peak_sum_channel can be used to calculate the signature. The signature can have the following equation:

signature = peak max channel _ max (max channel (t)) peak_sum_channel max (sum_channel (t))

A search-triggered noise rejection mode can be employed. When a detected activation is rejected due to a dirty signature, the search or scan mode should be automatically activated. Thus, when scanning blind, a user can search with all fingers extended trying to establish a frame of reference from which to start searching. This can activate multiple channels at the same time, thereby resulting in a poor signature.

With reference to FIG. 14, there is shown a state diagram for mounting proximity switches 20 in a machine state implementation, according to one embodiment. The machine state implementation is shown with five states including state 70 SW_NONE, state 72 SW.ACTIVE, state 74 SW_THRESHOLD, state 76 SW_HUNTING, and state 78 SWITCHACTIVATED. State 70 SW_NONE is the state where there is no detected sensor activity. The SW_ACTIVE state is the state in which some activity is detected by the sensor but it is not enough to activate the activation of the switch at that point in time. The SW THRESHOLD state is the state where the activity determined by the sensor is high enough to warrant triggering, searching / scanning, or random movement of the switch assembly. The 76 SW_HUNTING state is entered when the activity pattern determined by the switch assembly is compatible with the browse / search interaction. State 78 SWlTCH_ACTIVATED is the state in which the activation of a switch has been identified. In the 78 SWITCH_ACTIVATED state, the switch button remains active and no further selection is possible until the corresponding switch is released.

₂₂

MSXiCAN INSTITUTE

FROM THE nMEDA »

INDUSTRIAL

The state of the proximity switch assembly 20 changes according to the detection and processing of the detected signals. When in the SW_NONE state 70, the system 20 may advance to the SW_ACTIVE state 72 when some activity is detected by one or more sensors. If there is enough activity to warrant any activation, search or casual movement is detected, the system 20 can proceed directly to state 74 SW_THRESHOLD. When in the SW_THRESHOLD state 74, the system 20 may proceed to the SW_HUNTING state 76 when a pattern indicative of scanning is detected, or it may proceed directly to the switch on state 78. When a switch activation is in the SW_HUNTING state, a switch activation can be detected to change to the 78 SWITCH ACTIVATED state. If the signal is rejected and an inadvertent action is detected, the system 20 may return to state 70 SW_NONE.

With reference to FIG. 15, the main method 100 is shown for monitoring and determining when to generate a trigger output with the proximity switch arrangement, in accordance with one embodiment. Method 100 begins at step 102 and proceeds to step 104 to perform an initial calibration that can be performed one time. The calibrated signal channel values ​​are calculated from the raw channel data and the calibrated reference values ​​by subtracting the reference value from the raw data in step 106. Then, in step 108, from all readings From the signal channel sensors, the highest count value referenced as max_channel and the sum of all the readings from the channel sensors referenced as sum_channel are calculated. In addition, the number of active channels is determined. In step 110, method 100 calculates the recent range of the max_channel and sum_channel to later determine if the move is in progress.

After step 110, method 100 proceeds to decision step 112 to determine if any of the switches are active. If there is no active switch, method 100 proceeds to step 114 to perform a real time online calibration. Otherwise, method 116 processes the release of the switch in step

<img file="MX347131B_D0020.tif" />

IMPI

MEXICAN INSTTTUTE OF WIBAD INDUSTRIAL

116. Thus, if a switch is already active, then method 100 proceeds to a module where it waits and blocks all activity until ITS activation.

After real time calibration, method 100 proceeds to decision step 118 to determine if there is any channel lock indicative of recent activation, and if so, proceeds to step 120 to decrease the channel lock timer. If no channel locks are detected, method 100 proceeds to decision step 122 to search for a new max_channel. If the current max_channel changes such that there is a new max_channel, method 100 proceeds to step 124 to reset the max_channel, sum the ranges, and set the threshold levels. Thus, if a new max_channel is identified, the method resets the recent signal ranges and updates, if necessary, the search / scan parameters. If the SWITCH_status is less than SW ACTIVE, then the seek / scan signal is set equal to true and the switch state is set equal to SW_NONE. If the current max_channel does not change, method 100 proceeds to step 126 to process the max_channel state of bare finger (no glove). This may include processing the logic between the various states as shown in the state diagram of FIG. 14.

After step 126, method 100 proceeds to decision step 128 to determine if any switch is active. If activation of the switch is not detected, method 100 proceeds to step 130 to detect a possible presence of a glove on the user's hand. The presence of a glove can be detected based on a small change in the capacitance count value. Method 100 then proceeds to step 132 to update the past history of the max_channel and sum_channel. The active switch index, if any, is then output to the hardware-software module at step 134 before ending at step 136.

When a switch is active, a switch release process routine shown in FIG. 16. The breaker release processing routine 116 begins at step 140 and proceeds to decision step.

<img file="MX347131B_D0021.tif" />

142 to determine if the active channel is less than LVLRELEASE and, if so, ends at step 152. If the active channel is less than LVL_RELEASE then routine 116 proceeds to decision step 144 to determine if the

LVLDELTATHRESHOLD is greater than 0 and otherwise proceed to step

IMPI

INÍHTV! » MUdCAN · MLAPMHHMP INDUJTUAL

146 to raise the threshold level if the signal is stronger. This can be achieved by decreasing LVL_DELTA_THRESHOLD. Step 146 also sets the threshold, release, and active levels. Routine 116 then proceeds to step 148 to reset the maximum channel and add the history timer for the long steady signal search / scan parameters. The switch state is set equal to SW_NONE in step 150 before ending in step 152. To exit the switch release process module, the signal on the active channel has to drop below LVL RELEASE, which is an adaptive threshold that changes when glove interaction is detected. Releasing the switch button resets all internal parameters and starts a lockout timer to prevent further activations before a certain timeout, such as 100 milliseconds, has elapsed. In addition, the threshold levels are adapted based on the presence of gloves or not.

With reference to FIG. 17, a routine 200 is illustrated for determining the change of state from a SW_NONE state to a SW_ACTIVE state, according to one embodiment. Routine 200 begins at step 202 to process the SW NONE state and then proceeds to decision step 204 to determine if the max_channel is greater than LVL_ACTIVE. If the max_channel is greater than LVL_ACTIVE, then the proximity switch assembly changes state from a SW_NONE state to a SW_ACTIVE state and terminates at step 210. If the max_channel is not greater than LVL ACTIVE, routine 200 checks whether to reset the search signal in step 208 before ending in step 210. Thus, the state changes from a SW_NONE state to a SW ACTIVE state when the max_channel is driven above LVL_ACTIVE. If the channels remain below this level, after a certain waiting period, the signal

<img file="MX347131B_D0022.tif" />

. IMPI institute mwucanq^{Z 3 1} THE TWBMITY

INDUSTRIAL search, if set, resets to no search, which is a way out of search mode.

With reference to FIG. 18, a method 220 is illustrated for processing the state of the SW_ACTIVE state by changing to either the SW_NONE state or the SW_THRESHOLD state, in accordance with one embodiment. Method 220 begins at step 222 and proceeds to decision step 224. If max_channel is not greater than LVL_THRESHOLD, then method 220 proceeds to step 226 to determine if max_channel is less than LVL_ACTIVE and, if so, proceeds to step 228 to change the switch state to SW_NONE. In this way, the state of the state machine is moved from the SW_ACTIVE state to the SW NONE state when the max_channel signal drops below LVL_ACTIVE. A delta value can also be subtracted from LVL ACTIVE to introduce some hysteresis. If the max_channel is greater than the LVL_THRESHOLD, then routine 220 proceeds to decision step 230 to determine whether a recent threshold episode or glove is detected and, if so, sets the search on the signal equal to true in step 232 In step 234, method 220 changes the state to the SW_THRESHOLD state before ending in step 236. Thus, if the max_channel is driven above LVL_THRESHOLD, the state changes to the SW THRESHOLD state. If gloves are detected or a previous threshold event that does not result in activation is recently detected, the search / scan mode can be entered automatically.

With reference to FIG. 19, a method 240 is illustrated for determining the activation of a switch from the SW_THRESHOLD state, in accordance with one embodiment. Method 240 begins at step 242 to process the SW_THRESHOLD state and proceeds to decision block 244 to determine if the signal is stable or if the signal channel is at a peak, then method 240 proceeds to decision step 246 to determine if search or browse mode is active, and if so, skip to step 250. If the search or scan mode is not active, method 240 proceeds to decision step 248 to determine if the signal channel is clean and fast active and greater than a threshold, and then

<img file="MX347131B_D0023.tif" />

IMPI

ΙΝΤΓΤΤυΤΓ) MWUCANC klammumo

INDUSTRIAL if yes, sets the active switch equal to the maximum channel in step 250. Method 240 proceeds to decision block 252 to determine if there is an active switch and, if so, ends in step 256. If there is no switch active, method 240 proceeds to step 254 to initialize the search variables SWITCH_STATUS which is set equal to SWITCH_HUNTING and PEAK_MAX_BASE equal to MAX_CHANNELS, before ending at step 256.

In the SW_THRESHOLD state, no decision is made until a peak is detected in MAX_CHANNEL. Peak value detection is conditional on either a change in signal direction, or both the MAX_CHANNEL and SUM_CHANNEL remaining stable (bound to a range) for at least a certain range, such as 60 milliseconds. Once the peak is detected, the search signal is verified. If seek mode is off, the input ramp slope method is applied. If the SW_ACTIVE to SW_THRESHOLD is less than a threshold such as 16 milliseconds and the signature of the noise rejection method indicates that it is a valid trigger episode, then the state is changed to SWITCH_ACTIVE and the process is passed to the PROCESS_SWITCH_RELEASE module; otherwise, the seek signal is set equal to true. If the delayed activation method is used instead of activating the switch immediately, the state is changed to SW_DELAYED_ACTIVATION where a delay is applied at the end of which, if the current MAXCHANNEL index does not change, the button is activated.

With reference to FIG. 20, a virtual button method is illustrated that implements the SW_HUNTING state, according to one embodiment. Method 260 begins at step 262 to process the SW_HUNTING state and proceeds to decision step 264 to determine if the MAX_CHANNEL has fallen below the LVL_KEYUP_THRESHOLD, and if so, sets the MAX_PEAK_BASE equal to MIN (MAX_PEAK_BASE, MAX_CHANNEL) in the step 272. If the MAX CHANNEL has dropped below LVL_KEYUP_THRESHOLD, then method 260 proceeds to step 266 to use the first trigger channel of the search method to check if the episode should trigger the trigger for

<img file="MX347131B_D0024.tif" />

button. This is determined by determining whether the first and only channel is traversed and the signal is clean. If yes, method 260 sets the active switch equal to the maximum channel in step 270 before ending in step 282. If not

IMPI

IWSTmnV MHUCAFK

M LA nOPIWAB

MDUrnUAL traverses the first and only channel or if the signal is not clean, method 260 proceeds to step 268 to terminate and determine an inadvertent actuation and to set the SWITCH_STATUS equal to the SW_NONE state before ending in step 282.

After step 272, method 260 proceeds to decision step 274 to determine if the channel has clicked. This can be determined by whether MAX_CHANNEL is greater than MAX_PEAK_BASE plus delta. If the channel has clicked, the method 260 proceeds to decision step 276 to determine if the signal is stable and clean and, if so, sets the active switch state to the maximum channel in step 280 before ending in the step 282. If the channel has not clicked, method 260 proceeds to decision step 278 to observe if the signal is long, stable, and clean, and if so, proceeds to step 280 to set the active switch equal to the maximum channel before ending. at step 282.

The proximity switch assembly 20 may include a virtual button mode, in accordance with another embodiment. With reference to FIGS. 21-27, there is shown the proximity switch assembly having a virtual button mode and a method of activating the proximity switch with the virtual button mode, in accordance with this embodiment. The proximity switch assembly may include one or more proximity switches, each providing a sensing actuation field and control circuitry to control the actuation field of each proximity switch to detect actuation. The control circuit monitors the signals indicative of the trigger fields, determines a first stable amplitude of the signal over a period of time, determines a second subsequent stable amplitude of the signal over the period of time, and generates a trigger output when the second stable signal exceeds first stable signal by a known amount. The method can be employed by mounting proximity switches and includes the steps of generating a trigger field associated with each of one or more than a plurality of sensor sensors.

2β

OF THE PUOMDAL ·

INDUSTRIAL proximity and to monitor a signal indicative of each associated trigger field. The method also includes the steps of determining a first amplitude when the signal is stable for a minimum period of time and determining a second amplitude when the signal is stable for the minimum period of time. The method further includes the step of generating a drive output when the second amplitude exceeds the first amplitude by a known amount. As a result, a virtual button mode is provided for the proximity switch that prevents or reduces unintended or false activations that may be generated by a finger scanning a plurality of proximity switch buttons and changing direction or by a finger. covered by a glove.

In FIG. 21 shows scanning and activating a proximity switch for one of the signal channels labeled signal 50 when a user's finger slides across the corresponding switch, enters a scan mode, and proceeds to activate the switch. in virtual button mode. It should be appreciated that the user's finger can scan a plurality of capacitive switches as illustrated in FIGS. 10-12 wherein the signals associated with each of the corresponding signal channels are generated when the finger passes through the trigger field of each channel. A plurality of signal channels can be processed at the same time and the maximum signal channel can be processed to determine the activation of the corresponding proximity switch. In the examples provided in the signal diagrams of FIGS. 21-25, a single signal channel associated with a switch is shown; however, a plurality of signal channels can be processed. Signal 50 associated with one of the signal channels is shown in FIG. 21 rising to an active threshold level 320 at point 300, at which point the signal enters the scan mode. Thereafter, signal 50 continues to rise and reaches a first amplitude, at which point the signal is stable for a minimum period of time, shown as Tstable shown at point 302. At point 302, signal 50 is enters virtual button mode and sets a first base value Cbase, which is the count of the delta signal at point 302. At this point, the

<img file="MX347131B_D0025.tif" />

IMPI?

INSTITUTO MEXICAN · DE LA HUMEDAD INDUSTRIAL virtual button mode establishes an incremental activation threshold as a function of the base value Cbase multiplied by a constant Kvb. The trigger threshold for determining a trigger can be represented by: (1 + Kvb) x Cbase, where Kvb is a constant greater than zero. The virtual button mode continues to monitor the 50 signal to determine when it reaches a second stable amplitude during the minimum period of time Tstable that occurs at point 304. At this point 304, the virtual button mode compares the second stable amplitude with the first stable amplitude and determines whether the second amplitude exceeds the first amplitude by the known amount of Kvb x Cbase. If the second amplitude exceeds the first amplitude by the known amount, then a trigger output is generated for the proximity switch.

According to this embodiment, the signal channel must maintain a stable signal amplitude for at least a minimum period of time Tstable before entering the virtual button mode or determining switch activation. The sensor value when it enters virtual button mode is recorded as Cbase. The method monitors when a subsequent stable signal amplitude is achieved again before a timeout period. If a stable signal amplitude is achieved again before the timeout period expires with a delta count value greater than a desired percentage, such as 12.5 percent of the previous recorded Cbase, then the trigger is triggered. According to one embodiment, a percentage increase in the delta signal count of at least 10 percent is provided per Kvb x Cbase.

The multiplier Kvb is a factor of at least 0.1 or at least 10 percent of the Cbase value, according to one embodiment. According to another embodiment, the multiplier Kvb is set to approximately 0.125 which equates to 12.5 percent. The stable time period Tstable can be set to a time of at least 50 milliseconds, according to one embodiment. According to another embodiment, the stable time period Tstable can be set in the range of 50 to 100 milliseconds. Stable amplitude can be determined by the amplitude of the signal being substantially stable in a range within twice the estimated noise size in the signal from

<img file="MX347131B_D0026.tif" />

according to one embodiment, or within 2.5 to 5.0 percent of the signal level, according to another embodiment or a combination of twice the estimated signal noise plus 2.5 to 5.0 percent of the signal level, according to a further embodiment.

IMPI

INSTITUTO MEXICANC de la rnorittMB INBUITUAL

With reference to FIG. 22, a signal 50 is shown for a signal channel associated with a proximity switch that enters the scan mode at point 300 and proceeds until a first stable amplitude is reached when the stable signal amplitude exists for a period of time. minimum Tstable at point 302 where virtual button mode is entered. At this point, the Cbase value is determined. From there, the signal 50 is shown decreasing and again increasing to a second amplitude when the signal is stable for the minimum time period Tstable at point 306. However, in this situation, the second amplitude in the point 306 does not exceed the base value Cbase of the signal at point 302 by the known amount of Kvb x Cbase and, as a result, does not generate a trigger output for the switch.

With reference to FIG. 23, a signal 50 associated with a signal channel is illustrated that enters scan mode at point 300 and proceeds to reach a first amplitude for a stable period of time Tstable at point 302 where scan mode is entered. virtual button and Cbase is determined. Thereafter, signal 50 continues to rise to a second amplitude that is stable for the minimum time period Tstable at point 308. However, at point 308, the second amplitude does not exceed the base value Cbase of the signal that is set to the first amplitude at point 302 by the known amount of Kvb x Cbase, such that the switch mounting The proximity switch does not actuate a switch output. However, a new updated base value is generated for Cbase at point 308 and used to determine the known quantity for comparison to the next stable amplitude. Signal 50 is shown decreasing and then increasing until the third amplitude that is stable for the minimum time period Tstable at point 310. The third

ΙΜΡΙ

INSTITUTO MEXICANO Dt INOUCTUAL PETIMITY the amplitude exceeds the second amplitude by more than the known amount of Kvb x Cbase in such a way that an activation output is generated for the switch.

With reference to FIG. 24, another example of a signal 50 is illustrated that is entered into the scan mode at point 300 and continues to rise to a first amplitude that is stable for a minimum period of time Tstable at point 302 where the virtual button mode and Cbase is determined. Thereafter, signal 50 is displayed decreasing to a second amplitude that is stable for the minimum time period Tstable at point 312. At point 312, the second amplitude does not exceed the first amplitude by the known amount of Kvb x Cbase such that a signal drive is not generated. However, an updated base value Cbase is generated at point 312. Thereafter, signal 50 continues to rise to a third amplitude that is stable for the minimum time period Tstable at point 310. The third amplitude exceeds the second amplitude by the known amount of Kvb x Cbase, such that a drive or activation output is generated for the switch.

With reference to FIG. 25, another example of a signal 50 is shown for a signal channel that enters the scan mode at point 300 and proceeds to reach a first amplitude that is stable for the minimum period of time Tstable at point 302, and thus Therefore, it enters virtual button mode and determines Cbase. The signal 50 then continues to rise to a second amplitude that is stable for the time period Tstable at point 308. The second amplitude does not exceed the first amplitude by the known amount such that a switch actuation is not generated at this point. Thereafter, signal 50 is shown decreasing to point 314 and in the process of doing so, a reset timer waits since the last stable amplitude is received as shown by Treset. When the reset timer waits, at point 314, the virtual button mode is exited and the scan mode is entered once the virtual button mode is exited. When this occurs, the old Cbase determined

<img file="MX347131B_D0027.tif" />

IMPI

INSTITUTO MEXICANO DE LA PROPIEDAD INDUSTllAL is no longer valid. From there, signal 50 is shown rising to a third amplitude that is stable for the minimum time period Tstable at point 316. At this point, the third amplitude establishes an updated Cbase that is used to determine future activations of the switch. Thereafter, the signal 50 is further displayed decreasing below the active threshold value 320, in which case, the virtual button mode is exited without activations.

A method of activating a proximity switch with a virtual button mode using the proximity switch assembly is illustrated in FIGS. 26 and 27. With reference to FIG. 26, method 400 begins at step 402 and proceeds to acquire all signal channels associated with all proximity switches in step 404. The method 400 proceeds to decision block 406 to determine whether the state is set to the ACTIVE state, and if so, it checks for a switch release in step 414 before ending in step 416. If the state is not is set to the ACTIVE state, method 400 proceeds to step 408 to find the maximum channel (CHT). Next, once the maximum channel is found, routine 400 proceeds to step 410 to process the maximum channel (CHT) of the virtual button method before ending at step 416. The maximum channel of the virtual button processing method 410 is illustrated in FIG. 27 and described below. It should be appreciated that method 400 may include an optional step 412 to also process the maximum channel signal using a touch method to detect a user touching a proximity switch to generate a trigger output.

The maximum channel virtual button processing method 410 shown in FIG. 27 begins at step 420 and proceeds to step 422 to input the maximum channel signal. Therefore, the maximum signal channel associated with one of the proximity switches is processed to determine the virtual button mode state and switch activation. At decision step 424, method 410 determines whether the switch is set to the virtual button mode state and, if so, proceeds to decision step 426 to determine whether the signal channel value is less than the active threshold. If the signal channel is less than the

<img file="MX347131B_D0028.tif" />

IMPI *

INSTITUT · MUüCANC

MLEnuinUMD

MiurnuAi threshold active, method 410 proceeds to step 428 to set the state equal to

NONE and returns to the beginning. If the signal channel is not less than the active threshold value, the method 410 proceeds to decision step 430 to determine if the signal has a first stable amplitude for a time period greater than the stable time period Tstable. If the stable signal channel at the first amplitude is stable for a period of time greater than Tstable, the method 410 proceeds to decision step 432 to determine whether the signal channel is not stable for a period of time that exceeds the period of Treset reset time and otherwise return to step 422. If the signal channel is not stable for a period of time that exceeds the Treset reset time, the method 410 proceeds to set the state equal to the scan / search state and ends in step 460.

Again in decision step 430, if the signal channel is stable for a period of time that exceeds the stable time period Tstable, method 410 proceeds to decision step 436 to determine whether the Ch (t) signal is greater than Cbase by a known amount defined by Kvb x Cbase, and if so, sets the switch to active state to generate a trigger output before ending in step 460. If the signal does not exceed Cbase by the known amount of Kvb x Cbase, method 410 proceeds to set the new Cbase value at the current stable signal amplitude in step 440, before ending in step 460.

Again in decision step 424, if the switch state is not set to virtual button mode, method 410 proceeds to decision step 442 to determine if the state is set to scan state, and if so , proceeds to decision step 444 to determine whether the signal is greater than the active threshold, and otherwise sets the state equal to the NONE state and ends at step 460. If the signal is greater than the active threshold, method 410 proceeds to decision step 448 to determine if the signal is stable at an amplitude for a period of time that exceeds the minimum period of time Tstable, and otherwise ends at operation 460. If the signal is stable in a

<img file="MX347131B_D0029.tif" />

amplitude for a period of time that exceeds the minimum period of time

Tstable, the method 410 proceeds to step 450 to set the switch state to the virtual button state and set the new value Cbase for the signal channel in step 450 before ending in step 460.

IMPI

INSTHVTO MEXICANO W LA MtOHEBAD INDUSTRIAL

Again in decision step 442, if the switch state is not set to the scan / search state, method 410 proceeds to decision step 452 to determine whether the signal is greater than the active threshold, and otherwise , ends at step 460. If the signal is greater than the active threshold, method 410 proceeds to decision step 454 to set the state to the scan / search state before ending at step 460.

Thus, the proximity switch assembly having the virtual button method 410 advantageously provides better detection of virtual button switch activation and better rejection of unintended activations. The method 410 can advantageously detect a switch activation while rejecting unintended activations that can be detected when a finger scans the switch assembly and changes direction or in which the user's finger is wearing a glove. Enhanced actuation detection advantageously provides improved proximity switch mounting.

In this way, the determination routine advantageously determines the activation of the proximity switches. The routine advantageously allows a user to explore the proximity switch pads, which can be particularly useful in an automotive application, where driver distraction can be avoided.

The proximity switch assembly 20 may include a flexible material that lines the proximity sensor, and the control circuitry may activate a proximity switch based on a signal generated by the sensor relative to a threshold when a user's finger presses. the flexible material, according to a further embodiment. In this embodiment, the proximity switch assembly 20 can operate in virtual button mode and can provide better signal detection by employing the flexible material that deforms.

<img file="MX347131B_D0030.tif" />

IMPI

INSTITUTO MÜUCAN DE LA PAUMWAL INDUSTRIAL to allow the user's finger to move closer to the proximity sensor. Furthermore, a void space in the form of an air pocket can be provided between the flexible material and the proximity sensor and a raised or raised surface can be further provided in the flexible material.

With reference to FIGS. 28A-31, there is shown the proximity switch assembly 20 employing the flexible material and operating in a virtual button mode and a method of activating the proximity switch using the flexible material in the virtual button mode , according to this embodiment. The proximity switch assembly 22 may include a proximity sensor, such as a capacitive sensor, that generates an actuation field. It should be appreciated that a plurality of proximity sensors 24 may be employed where each generates a trigger field. Proximity sensors 24 are shown provided on the surface with a rigid substrate, such as a polymeric roof console 12, in accordance with one embodiment. Each of the proximity sensors 24 can be formed by conductive printing ink on the surface of the polymeric ceiling console 12. Proximity sensors 24 may be formed in another manner such as by mounting preformed conductive circuit traces on a substrate in accordance with other embodiments.

A flexible material 500 is shown covering the substrate 12 and is intended to provide the touch surface for a user's finger 34 to interact with the proximity sensors 24 to activate the switches 22. The flexible material 500 is shown formed as a cover layer that can be made of an elastic material, including rubber, according to one embodiment. Flexible material 500 is flexible with respect to underlying substrate 12 which is generally rigid. Flexible material 500 overlaps proximity sensor 24 and is deformable when a user's finger 34 applies pressure such that finger 34 compresses flexible material 500 and moves inward toward proximity sensor 24 such as shown in FIG. 28C. According to one embodiment, the flexible material 500 may have a layer thickness in the range of

<img file="MX347131B_D0031.tif" />

IMPI

INSTtTUT · MEXICAN

OF THE INBUrnUAL niCWIUMD about 0.1 to 10 millimeters and more preferably in the range of 1.0 to 2.0 mm.

Proximity switch assembly 20 employs control circuitry to monitor the trigger field associated with each sensor 24 and determine a triggering of a proximity switch based on a signal generated by proximity sensor 24 relative to a threshold when a Finger 34 of a user presses on flexible material 50. The control circuit can determine a stable amplitude of a signal generated by the proximity sensor 24 for a predetermined period of time and can generate a switch activation output when the stable output exceeds a threshold value. According to one embodiment, the control circuits can determine a first stable amplitude of a signal over a period of time, can determine a subsequent second stable amplitude of the signal over a period of time, and can generate a switch activation output. proximity associated with the signal when the second stable signal exceeds the first stable signal by a known amount.

With reference to FIGS. 28A-28D, the mounting of proximity switches 20 is illustrated employing a flexible material 500 that overlaps one or more proximity sensors 24, in accordance with a first embodiment. As shown in Fig. 28A, a finger of a user 34 shown in a first position contacts the surface of flexible material 500 at a near but laterally offset location of a proximity sensor 24. In FIG. 28B, the user's finger 34 is shown in motion by sliding sideways to a second position aligned with a proximity sensor 24 without applying pressure to the flexible material 500. This can occur when a user is scanning the proximity sensor assembly 20 in a scan / search mode without the intention of activating switch 22. In FIG. 28C, the user's finger 34 is shown applying a force toward the proximity sensor 24 to depress the flexible material 500 to move the user's finger 34 to the third position closest to the proximity sensor 24. The user's finger 34 can thereby press and deform flexible material 500 to move closer to proximity sensor 24 and can

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Mexican institute IMPI

MUnOMUMB

INDUWUAL furthermore crush and thereby flatten the finger 34 against the substrate 12 to provide a greater surface area or volume of the finger in close proximity to the sensor 24 which provides a greater interaction with the associated activation field and, therefore, a greatest sign.

The sequence of episodes shown in FIGS. 28A-28C is further illustrated in the signal response shown in FIG. 28D. The signal 506 generated by the proximity sensor 24 is shown rising to a first level 506A indicative that the user's finger 34 is in contact with the proximity switch assembly 20 at the first laterally distant position of the proximity sensor 24 as seen in FIG. 28A. Signal 506 is then raised to level 506B indicative that user's finger 34 shown in the second position aligned with proximity sensor 24 without applying force as shown in FIG. 28B. Thereafter, signal 506 then rises to a third elevated level 506C indicative that the user's finger 34 applies a force in the third position to depress flexible material 500 as shown in FIG. 28C. Thus, the signal 506 is much larger when the user's finger 34 presses on the flexible material 500 allowing virtual button detection.

The control circuit monitors the actuation field and determines an actuation of the proximity switch based on signal 506 relative to a threshold when the user's finger presses on flexible material 500. Process circuitry may include controller 400 that is shown in FIG. 5 to execute a control routine that may include routine 520 which is shown and described herein in connection with FIG. 31. As such, the process circuits can use a virtual button method as described above to detect a scan mode and the virtual button activations of one or more proximity switches.

The proximity switch assembly 20 may be further configured with a flexible material 500 has a raised or raised touch surface portion 502 aligned with each proximity sensor 24 and a gap

IMPI

INSTITUTO MEXICANO DE LA FBOMIÜAD INBUSTUAL vacuum or air gap 504 disposed between raised portion 502 and proximity sensor 24 as shown in FIGS. 24A-24C, according to another embodiment. In this embodiment, the air gap 504 formed between the flexible material 500 and each proximity sensor 24 provides a greater travel distance during activation of the switch that can also serve as a haptic feel for a user. Air gap 504 may have a height distance of less than 5.0 millimeters, in accordance with one embodiment, more preferably in the range of 1.0 to 2.0 millimeters. The raised portion 502 of the flexible material 500 maintains the user's finger 34 most distal from the proximity sensor 24 in the non-depressed state. As shown in FIG. 29A, a user's finger 34 contacts the mounting proximity switch 20 at a location close to but laterally spaced from the proximity sensor 24 at a first position. Next, in FIG. 28B, the user's finger 34 is moved to a second position aligned with the proximity sensor 24 on top of the raised portion 52 of the flexible material 500. In this position, a finger of a user 34 may be scanning the proximity switches 22 in a scan / search mode, with no intention of activating a switch. In FIG. 29C, the user's finger 34 is shown in the third position depressing the flexible material 500 on top of the raised portion 502 in order to move the finger 34 to a fully depressed state that compresses the flexible material 500 and the air gap. 504 to allow the user's finger to be in a closer position relative to the proximity sensor 24. When this occurs, the control circuits detect an intention of the user to activate the switch 22 and generate an activation output signal.

With reference to FIG. 28D, the signal 506 generated in response to activation of the trigger field by the proximity sensor 24 is shown in relation to the actuations of the user's finger shown in FIGS. 29A-29C. Signal 506 is shown rising to a first level 506A indicative that the user's finger 34 is in the first position in contact with the proximity switch assembly 20 at a lateral distance from the sensor 24 which is₃₉ iMPí ^ a

OF THE FKMEDA »

INDUSTRIAL shown in FIG. 29A. Signal 506 is held at first level 506A as also shown by level 506B while the user's finger is raised to the second position on raised portion 502 aligned above proximity sensor 24 without depressing flexible material 500, as shown in FIG. 29B. Raised portion 502 thereby allows signal 506 to maintain a low signal when a user's finger is in a scan mode and does not intend to activate switch 22. Signal 506 is displayed rising to a higher level. raised 506C indicative that the user's finger 34 is depressing the flexible material in the third position by compressing the raised portion 502 and the air gap 504 as shown in FIG. 29C to activate switch 22. The control circuits process signal 506 to detect an activation of switch 22 when this occurs and may further detect a scan / search mode as described above.

With reference to FIG. 30, a state diagram is shown for mounting proximity switches in another state machine implementation utilizing flexible material and virtual button mode, in accordance with one embodiment. The state machine implementation is shown with four states, including wait state 510, search state 512, virtual button state 514, and button press state 516. Wait state 510 is entered when the signal is below a threshold indicative that no sensor activity is detected. Search state 512 is entered when the signal is greater than a threshold indicative that the determined activity is compatible with a search / search interaction. The virtual button state 514 is entered when the signal is stable. The push button state 516 is indicative of forceful pressure on the switch to compress the flexible material once it is in the virtual button state. When the signal reaches a certain threshold, the search / scan mode 512 is entered. When the signal is stable and greater than a base level, the virtual button mode 514 is entered. If the signal is stable and greater than a base level plus a delta zenith value,

IMPI

INSTITUTE MWCANC

I heard THE PSOA1EBW INMJSTUAL 516 button press mode is entered. It should be appreciated that the base level can be updated as described above.

With reference to FIG. 31, routine 520 is shown for controlling proximity switch mounting and actuation method using flexible material as described above in connection with FIGS. 28A-30 and described herein. Routine 520 may be stored in memory 48 and executed by controller 40, in accordance with one embodiment. Routine 520 begins at step 522 to process the largest or maximum signal channel, which is the maximum signal channel associated with one of the proximity switches. In step 524, the maximum signal channel is input to the controller. Next, in decision step 526, routine 520 determines whether the current state is set to the wait state and, if so, proceeds to decision step 528 to determine whether the maximum signal channel is greater than a threshold. . If the maximum signal channel is not greater than the threshold, the routine 520 ends in step 530. If the maximum signal channel is greater than a threshold, the routine 520 proceeds to set the state in the search state in step 532 before ending at step 530.

Back in decision step 526, if the state is set to the wait state, routine 520 proceeds to decision step 534 to determine if the state is set to the search state, and if so, proceeds to step Decision 536 to determine whether the maximum signal channel is less than a threshold. If the maximum signal channel is less than the threshold, routine 520 proceeds to step 538 to set the state to the standby state and then ends at step 530. If the maximum signal channel is not less than threshold 536, routine 520 proceeds to decision step 540 to determine if all signal channels are stable, and if not, ends at step 530. If all signal channels signal are stable, routine 520 proceeds to step 542 to set the state equal to the virtual button state and then sets the channel base to the maximum signal channel in step 544 before ending in step 530.

Again at decision step 534, if the state is not set equal to the search state, routine 520 proceeds to decision step 546 to determine

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ΙΝΕΤΓΠπ »MEXICAN □ ί la reonuMt (NBUJTtlAL if the state is in the virtual button state and otherwise proceeds to step 548 to set the state to the push button state. From there, routine 520 proceeds to decision step 550 to determine whether the maximum signal channel is less than a threshold, and otherwise ends at step 530. If the maximum channel is less than a threshold, routine 520 sets the state equal to the wait state in step 552 and then releases the activation in step 554 before ending in step 530.

Again in decision step 546, if the state is set equal to the virtual button state, routine 520 proceeds to decision step 556 to determine if the maximum signal channel is less than a threshold, and if so, sets the state equals the wait state in step 558 before ending in step 530. If the maximum signal channel is not less than the threshold, routine 520 proceeds to decision step 560 to determine whether the virtual button timer is greater than a timeout, and if so, sets the state to the state of search at step 562 before ending at step 530. The virtual button timer may be set in a range of one to three seconds, according to one embodiment. If the virtual button timer does not time out, routine 520 proceeds to decision 564 to determine if all signal channels are stable, and otherwise ends at step 530. If all signal channels are determined to be stable, routine 520 proceeds to decision step 566 to determine if the rubber zenith is depressed which can be determined by the maximum signal channel being greater than a signal channel base summed with a delta zenith signal value. If the rubber zenith is depressed, routine 520 proceeds to decision step 568 to set the state equal to the button press state and then generates a maximum signal channel activation at step 570 before ending at step 530. If the rubber zenith is not depressed, routine 520 proceeds to step 572 to determine that the finger is still sliding and to update the base signal ChBase to the maximum signal channel in step 572 before ending in step 530.

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IMPI iNrrmrro majucaaic

M LA PW11DAP

INDUSTRIAL

In this manner, the proximity switch assembly 20 having the flexible material 500 and the virtual button mode advantageously provides better detection of virtual button switch activation to improve rejection of unintentional activations. Method 520 can advantageously detect activation of a switch while rejection of unintentional activation of the switch can be detected when a finger scans the switch assembly. Better actuation detection advantageously provides an improved proximity switch mounting which may be particularly advantageous or useful in an automotive application where distraction of the driver can be avoided.

It should be understood that variations and modifications may be made to the aforementioned structure without departing from the concepts of the present invention and it should be further understood that such concepts are intended to be covered by the following claims unless these claims by their language state expressly otherwise.

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IMPI