Vehicle seat for passenger motor vehicle

The invention relates to a vehicle seat for a motor vehicle according to the features of the preamble of claim 1.

JP 09109757 A shows a vehicle seat of an active having the seat suspension. There are-derived from the vehicle floor Vibrations by electrical actuators compensated. A control device determined by acceleration sensors the acceleration of the vehicle and the seat and controls electric actuators so that the vibrations of the vehicle are largely compensated.

The the present invention underlying task there, a vehicle seat with an active seat suspension for a to provide motor vehicle, at different Vibrational excitations is particularly comfortable and a possible having good vibration suppression.

This object is inventively achieved by a vehicle seat solved with the features of claim 1.

The vehicle seat has a seat structure with a seat cushion and associated preferably with the seat cushion mechanically Backrest on which a of a control device controllable support device to a vehicle-fixed Seat substructure is mounted. The control device has a Controller structure on which two types of controllers with one another to a common transmission link with a particular transfer characteristic combined. You can use both types of controller using a stored in the control device Crossfading combined. This crossfading here has a history, that of the vibration amplitude the seat structure, preferably the seat cushion depends. unreacted This usually means Controller structure, it is possible two different controller types to consider, depending on the amplitude of the seat structure or the seat cushion different control behavior exhibit. Thus it is achieved that over a wide Vibration amplitude range of the seat structure, or the seat cushion an individually customized controller characteristic comes into play and thus the active seat suspension one of each oscillation amplitude range particularly having well-adjusted controller characteristic.

In a device may be provided in particular that the first type of controller, a control response of a passive suspension Seat, ie a seat of a passive spring / damper system is sprung, has. The second type of controller , a control behavior of an active suspension seat exhibit. This makes it possible that in an oscillation amplitude range the vibration and / or damping behavior the seat of the invention in about the vibrational and / or damping behavior of a passive suspension Seat corresponds. In another vibration amplitude range is it about the second type of controller, a controller behavior modeled, which corresponds to an active suspension seat.

The goal of an active seat suspension is to vibrations or Vibrations that can affect an occupant to suppress. This creates a conflict with vibrations have a large vibration amplitude. Leaving such Vibrations by means of an active seat suspension suppress, were large relative movements between seat and vehicle required. For the takes the seat mechanism on very large stroke movements to be designed, what usually the space in vehicles, especially in passenger cars not available. Also, by such a large relative movements between cab and seat the operation of steering and / or affected pedals sustainable.

To resolve this conflict, is the present Invention designed a control device with a control structure, which in particular higher-frequency vibrations largely suppressed and at the same time low-frequency vibrations with great oscillation amplitude predominantly from the console transmits on the seat. This may in particular implemented by be that the first controller type a passive suspension Seat modeled and then is used when relatively large stroke low-frequency vibrations occur. Of the second controller type modeled here, the control behavior of a active suspension seat, which individually harder or softer is adjustable, preferably adapted to the respective occurring vibrations. With the second type of controller a active suspension seat succeeds then a small electrical field strength to reach the seat, which the the driver preset rest position of the seat, a high vibration suppression guaranteed.

In one embodiment it may be provided that to a seat cushion or a backrest or a seat frame Sensors for recording vibrations of the whole seat structure are arranged. This is a simple design allows configuration of the vehicle seat.

In particular, in one embodiment, it is provided that the crossfading at oscillation amplitudes of the seat structure or of the seat cushion in an area above one in the Control device variably definable amplitude maximum value only the first controller type considered. As a result, that particularly very large amplitudes above a previously defined amplitude maximum value there are a control behavior is realized, which first the Controller type corresponds. This can be achieved in that the vibration and / or damping characteristics, for example a passively damped conventional automobile seat for large amplitudes takes effect.

Furthermore it can be provided that the crossfading at oscillation amplitudes of the seat structure type resp seat cushion in an area below one in the control device variably definable fixed amplitude value a constant Blending ratio of the first type to the second controller comprising controller type. This makes it possible that, in a Range of small oscillation amplitudes modeled a control behavior is that an active suspension vehicle seat and corresponds to the best possible small-signal behavior is the best possible vibration suppression has.

Further, it may be provided that for a particular Oscillation amplitude range, preferably at small Vibration amplitudes below a definable amplitude minimum value, a constant blending ratio of two types of controllers based on a storable in the control device is fading parameter fixed. In this case, determined this transition parameters experimentally and be stored in a memory of the control device or by a user to be changed individually.

In an advantageous embodiment, it is provided that the Control device to transition parameters based the Rectified value of the conducted by the Seat Vibration determined and individual stores. This is a particularly good adaptation of the active seat suspension to the prevailing Road conditions and appearing vibrations possible.

To ensure a particularly good vibration suppression in a Area between the amplitude maximum value and the range ensure the constant crossfading is provided that the blending function in the oscillation amplitudes Seat structure type resp seat cushion in a range between the amplitude maximum value and the amplitude minimum value a having parabolic shape.

In one embodiment, it is provided that the control device a plurality of sensors which generate the test signals based where the control device, the support device controls. Especially it is provided that the vehicle seat is one degree of freedom having. That is, the seat structure, in particular movably the seat cushion in one degree of freedom and said control means a vehicle-installed first acceleration sensor and a with the Seat second acceleration sensor connected to receive the acceleration of the vehicle and the seat structure has or seat cushion. This allows the acceleration values detected by the seat structure and vehicle separated and Rules are used.

To achieve a particularly fine control is provided, that the device has a third sensor namely has a displacement sensor, the relative position of the seat cushion and seat structure determined. This additional Displacement sensor, in addition to the acceleration values ​​have a position information supplies, offsets can be avoided and so a particularly fine control of the vibration behavior be achieved.

In addition to the movable support of the seat structure or the Seat cushion in one degree of freedom, the seat structure or mounted the seat cushion also movable in several degrees of freedom be. So it is possible to provide the cushion for storing recordable movable in two or three degrees of freedom. A first degree of freedom can be, for example, vertical up and down movement of the seat towards a represent the vertical vehicle axis and may referred to as Z-axis will. A second degree of freedom can the movement of Seat in the vehicle longitudinal direction so be an X-axis. To which may be a third degree of freedom are considered, the for example, includes the Y-axis. Alternatively, a well Another degree of freedom, for example, a pitch or Roll and a longitudinal or transverse axis of the seat or account of the vehicle and controlled by means of Supporting device are compensated.

In order for a seat with more than one degree of freedom, a particularly good Regele Gung enable is provided that the control device depending controlled degree of freedom each one with the vehicle acceleration sensor and associated connected with a the seat structure or the seat cushion second acceleration sensor having a degree of freedom to separate intrusion of the acceleration values ​​of to allow vehicle and seat cushions. Furthermore, be provided that the control device comprises a controller structure having, each controlled degree of freedom a separate independent regulator modeled, of the regulation Supporting device selectively allows for a degree of freedom.

To Systemic coupling degrees of freedom to one another to prevent, it can be provided that in the control device Compensation measures, preferably an equalizer or decoupling network is provided. These compensation measures prevent inherent linkages between the individual degrees of freedom or this while.

The active seat suspension, a control device in the form having an electronic control unit, which has a Microprocessor, electronic memory and interfaces having. Also, the control device or parts of the control device be realized by means of analog computers.

The invention is based on a closer shown in the drawings Embodiment hereinafter described. Show it:<dl tsize="6"><dt>Fig. 1</dt><dd>a schematic side view of a vehicle seat with active seat control,</dd><dt>FIG. 2</dt><dd>a schematic representation of the fading function Control apparatus,</dd><dt>Fig. 3</dt><dd>a schematic structure of the control apparatus for Determining a fade coefficient,</dd><dt>Fig. 4</dt><dd>a schematic structure of the control structure the control device.</dd></dl>

1 shows a schematic side view of a with a driver occupied vehicle seat 1. The vehicle seat is located in a commercial vehicle cab, which in the figure 1 schematically the instrument panel 15 and a steering wheel 14 and the cab floor is indicated. Using these parts can the relative mounting position of the vehicle seat 1 in recognize the vehicle cabin.

The vehicle seat 1 has a seat structure, the seat cushion a 11, one connected to the seat cushion backrest 12, and having a bearing seat frame. A seat structure 31 is fixedly connected to the vehicle floor. On the Seat substructure 31 is a seat platform 36, a seat cushion 11 movably. The seat cushion 11 is a seat frame connected to a backrest 12 of the vehicle seat. At the top End of the backrest 12, a headrest 13 is arranged.

A controllable by a control device 4 supporting device 6 is between the seat base 31 and the seat cushion 11 arranged. The support link 6 connects the seat cushion 11 movable covers with the fixed vehicle seat substructure 31 and the seat pedestal, a Paralellogrammlenker 33 and a spring / damper system. The seat cushion 11 is on the supporting device 6 in the direction of the vehicle vertical axis, the time direction, and in the direction of the vehicle longitudinal axis, the X-direction, movably. Thus, the illustrated in Figure 1 Vehicle seat two degrees of freedom Z and X. The transmission behavior the supporting device 6 is determined by the control device 4 controlled.

The seat structure 31 includes a support bracket 32 ​​fixed is connected to the vehicle floor. On the support beam 32 is arranged a support damper 35a and a support spring 34a. The support spring as well as the supporting dampers are at their connected one end to the support beam 32 and the other at its End with a Parallelogrammlenkergestänge 33. The Parallelogrammlenkergestänge 33 enables movement of the Seat cushion 11 in the Z direction and ensures a parallel shift the related parallelogram 33 Seat pedestal 36 for all oscillating and vibrating movements of the vehicle seat. 1

The movement of the vehicle seat 1 and the seat cushion 11 in the Z direction is assisted by the spring damper system 34a, 35a determined. Because the transmission of this spring damper system which is a part of the active seat suspension represents, is by controlling the forces of the damper 35a changeable. The damper 35a has for this purpose an electric Actuator, which is controlled by the control device. 4

Assigned to the degree of freedom in the Z direction are 3 sensors wherein a first sensor 21a fixed to the vehicle on the supporting beam 32 is arranged. This first sensor is an acceleration sensor 21a formed and takes the acceleration values the vehicle or the vehicle cab on. On second sensor 22a is positioned seat cushions laid on the seat pedestal 36th It is likewise designed as an acceleration sensor. This second sensor 22a serves to receive the acceleration values of the seat cushion 11. Further, a third sensor 23a, which is disposed on the damper 35a is, and the relative position of the seat 36 and the pedestal the seat cushion 11 relative to the lower seat structure 31 and receives the vehicle cabin. These three Sensors are connected by a signal line 24a to the control device 4, and delivering it to them the relevant Interference for the degree of freedom Z.

The seat platform 36 has a slide 37 on which a movement the seat cushion 11 allowed in the vehicle longitudinal direction. The vehicle longitudinal direction extends in the direction of travel Vehicle. The movement of the carriage 37 is in this case of a Spring damper system, consisting of the spring 34b and the Damper 35b controlled. The damper 35b has in this case a linear electric motor which by the control device 4 is controlled by the vibration characteristics of the seat in the X direction, ie to regulate the degree of freedom X.

Further, three sensors 37 are arranged on the carriage, associated with the degree of freedom X. A first acceleration sensor 22b is fixed to the vehicle connected to the seat platform 36, so that the vibrations in the X direction of the vehicle cab be taken up by this acceleration sensor. A second acceleration sensor 22b on the carriage 37 arranged such that it is mechanically secured to the seat cushion 11 connected and thus the acceleration of the seat cushion 11 receives. A third sensor 23b is attached to the Slide 37, or on the damper 35b arranged so that it the relative position of the seat cushion 11 relative to the Cabin or the seat platform 36 receives. These three sensors deliver measured quantities for the control device 4 for the degree of freedom in the X direction, and are via a signal line 24 to the control device 4 connected.

The control device 4 includes a control structure, which a separate controller for each degree of freedom X or Z provides. For each degree of freedom X or Z, the control device 4 a separate controller on which internally identical is constructed. Each knob is made of a Combination of two types of controllers 41 and 42. The output signal the control device 4 is separated by degrees of freedom. The output 25a controls the supporting device 6 of the vehicle seat in the X direction, in particular the output line 25a is connected to the damper 35b and so controls the response of the degree of freedom X. The output 25b of the control device 4 is connected to the Damper 35a for controlling the transmission behavior of the Z-degree of freedom connected.

In order to an active seat suspension a wide a range of vibration amplitudes consistently good comfort to achieve is in the control apparatus 4, a controller structure implemented, the two types of controllers 41 and 42. These two types of controllers 41, 42 are based on a blending function 43 combined, which crossfading 43 is shown in detail in FIG. 2 This crossfading is independent of the static seat adjustment be. The blending function 43 depends on the deflection the seat to the rest position from, so the vibration amplitude φ and supplies depending on the oscillation amplitude φ different crossfade values ​​based on which the controller 41 or 42 together to form a common output Faz be combined.

In a region of small oscillation amplitudes φ of the seat, ie in an area which is smaller than φmin and extends to -φmin, is the setting of the controller combination constant. That is, the controller types 41 and 42 be at a constant ratio K min respectively (1 - Kmin) combined to a possible optimum Vibration suppression in the small signal behavior of active get fit regime. Exceeds the amplitude of vibration the seat structure or the seat cushion 11 φmin the value, so starts the dynamic display the passive seat adjustment, which is modeled in the controller type 41st For this purpose a parabolic history crossfading modeled 43, of the value φmin to the value of the oscillation amplitude φmax enough.

is φmax From the value the output of the control structure 4 mainly from the regulator 41, the passive seating arrangements modeled determined. Thus, to reach an adaptation or a crossfading of different control settings, a possible good to both small-signal behavior to obtain vibration suppression as well as in large-signal behavior an optimum for the driver possible comfort setting the vehicle seat through.

In addition to the vibration amplitude φ or the parameters φmin and φmax remains the Umblendkoeffizient K.sub.min a variable in the control device 4 size. to at prolonged suggestions of the cab with a large amplitude carry the seat to the car better can, the parameter K min is made variable. To determines the control device 4 the parameter K.sub.min way of estimated direct guidance value of the seat structure or the seat cushion 11 by-oscillation around the rest position. Here, the rectified value is then normalized to a range of 0 to the first Accordingly, over the Value K min reached an amplitude control of Umblendvorganges, the best possible and most optimized adaptation of allows control behavior of the active seat suspension.

In the figure 3, the structure of the control device 4 is shown, which allows the determination of Umblendfaktors K-min. To this end, the amplitude value is filtered φ and a mean magnitude of the oscillation amplitude of φ Seat determined. Then, from this mean magnitude the amplitude φ the rectified value is determined and normalized. From these values, the control device determines the Umblendkoeffizienten K.sub.min means the controlled comfort adaptation the active seat control on the basis of of the performed vehicle seat 1 performed vibration amplitude becomes.

In Figure 4 is an example of the control structure of the control device 4 presented for the degree of freedom z. aim The scheme is, the oscillation amplitudes of the seat is on Zero to regulate. For this, the signal of the acceleration sensors 21a and 21b or 22a and 22b and the signal the actuator position and the relative speed of the actuator used as a measurement of the control device. 4 These are measured variables for both types of controller 41, for the purely passive Seat, and 42 supplied for the active seat. At the is a model which takes into account the geometry of seat 44 implemented in the controller structure. On the basis of the oscillation amplitude φ the seat structure or the seat cushion 11, according to the above-described structure of the control device 4 crossfading 43 or the blend ratio K.sub.min determined. With the help of the factor is the K.sub.min Output of the controller 41 and the controller 42 each combined into one output Faz. This output signal drives the actuator of each controlled degree of freedom. In addition, in the control structure nor the characteristic of the actuator are taken into account to the best possible to reach and accurate control of the seat.

The controller structure shown in Figure 4 for the degree of freedom Z can also be used for the degree of freedom X, in which the corresponding sensor signals and reference signals be replaced by Z by X. Likewise, a tilt or roll of a vehicle seat to be considered, where appropriate for the degree of freedom a tilting degree of freedom α, is used.