Illuminated display remote control has light sensors on neon tubes

Remote monitoring system for luminous display device.

display maintenance system

The present invention relates to remote monitoring systems for light display devices, in particular illuminated signs.

The object of the present invention is in particular to improve the reliability of lighting devices, in particular to allow preventive action.

To this end, according to the invention, a remote monitoring of the type in question is characterized in that it comprises:

at least one light display device comprising a plurality of light elements each having a certain light emission, light sensors arranged to measure the light emission of at least some of the light elements of the display device, a local central remote monitoring connected to the light sensors of the display device to receive light measurements made by said light sensors, and a central station, remote from the luminous display device and connected to the local central monitoring station of the luminous display device by a telecommunications link.

Thanks to these arrangements, it is possible to follow the evolution of the light intensity emitted by the light elements of the display device, which makes it possible to follow the aging of these light elements and to trigger preventive maintenance operations, so as to replace the light elements when they reach the end of their life, but before they fail.

In preferred embodiments of the invention, one can optionally also have recourse to one and / or the other of the following arrangements:

- the local central monitoring station is suitable for measuring an ambient temperature and a supply voltage of the light elements, and for correcting the light measurements that it receives from the light sensors, so as to obtain corrected measurements equivalent to conditions standardized temperature and voltage;

- the local remote monitoring unit is adapted to measure an ambient temperature and a supply voltage of the light elements, and to communicate said ambient temperature and said supply voltage to the light sensors, the light sensors being adapted to correct the measurements of light which they produce as a function of said ambient temperature and of said supply voltage, so as to obtain corrected measurements equivalent to standardized temperature and voltage conditions, the light sensors being adapted to transmit these corrected measurements to the local remote monitoring center;

- light elements include neon tubes;

- Each light sensor is suitable for measuring the light emission of a single light element;

- each light sensor is fixed against a light element;

- the luminous display device is placed in a place closed to the public and the local central monitoring station is connected to at least one intrusion sensor suitable for detecting the presence of a person in the vicinity of the display device, said central local remote monitoring being adapted to immediately warn the central station upon detection of a person in the vicinity of the luminous display device;

- the local central monitoring station comprises at least one protection cabinet which can be opened, and interrupting the display said local central monitoring station comprises at least one contact sensor suitable for detecting the opening of said cabinet, the local central monitoring station being adapted to immediately notify the central station when said local central monitoring station detects an opening of the cabinet;

- the local central monitoring station is adapted to immediately notify the central station when said local central monitoring station detects a zero supply voltage;

- the luminous display device comprises an emergency cut-off system suitable for the power supply of said light device, the local central monitoring station being connected to said emergency cut-off system to detect an actuation of this cut-off system. emergency, and the local central monitoring station being adapted to immediately notify the central station when it detects an actuation of the emergency cut-off system;

- the luminous display device is an illuminated sign.

Other characteristics and advantages of the invention will become apparent from the following description of one of its embodiments, given by way of non-limiting example, with reference to the accompanying drawings.

On the drawings:

- Figure 1 is a schematic view of a remote monitoring system according to one embodiment of the invention,

- Figure 2 is a schematic view of a light sensor belonging to the remote monitoring system of Figure 1,

- Figure 3 is a perspective view of the light sensor of Figure 2,

- and Figure 4 is a block diagram of part of the remote monitoring system of Figure 1.

In the various figures, the same references designate identical or similar elements.

As shown in Figure 1, the invention relates to a remote monitoring system for a light device 1 such as a lighted sign, display mounted by comprising, for example, on the a plurality of roof of a building 2 light elements and light 3.can be

Advantageously, the elements each constituted by a neon tube or by a series of neon tubes mounted in series. In the example shown, each light element 3 forms a character which can be a number, a letter, or other, but of course, each light element 3 could also be a figurative element.

To monitor the operation of the display device 1 and in particular the aging of the light elements 3, the remote monitoring system according to the invention comprises light sensors 4 which are arranged to measure the light emission of at least some of the light elements. 3 of the display device. Preferably, as shown, the remote monitoring system comprises a light sensor 4 for each light element 3 representing a character, a number or another figurative element.

Each light sensor 4 is mounted so as to measure only the light intensity of the light element 3 to which it is assigned. When the light elements 3 are neon tubes or sets of neon tubes, the light sensors 4 can advantageously be fixed directly against the neon tubes, for example by means of a wire tie or the like which is passed around the tube. sensor 4 and the corresponding neon tube.

The various light sensors 4 of the light display device 1 are connected to a local central monitoring station 6, for example by means of a bus link 5, in particular an RS485 type link, or the like.

such as a phototransistor the transparent window

This local central monitoring station communicates by means of a telecommunications link 7 with a central station 8 which may for example include a microcomputer and which can communicate with a plurality of local central monitoring stations corresponding to several display devices. luminous 1. The telecommunication link Ί can be a wire link passing through the switched telephone network, a radio telephone link of GSM or other type, etc ...

As shown in FIG. 4, each light sensor 4 may comprise an external housing 9 which is fixed for example against a luminous element 3 as explained above, the housing 9 being opaque and comprising a transparent window 10 arranged against the luminous element 3. so as to capture only the light emission of this single element 3.

Inside the housing 9, the light sensor 4 comprises for example:

a component 11 for measuring light intensity PHOTOTRANS.), arranged behind 10 to measure the light intensity emitted by the light element 3 (by way of example, a phototransistor of the SFH 3410 type sold by the company OSRAM can be used ), an adjustable gain amplifier 12, connected to the output of the phototransistor 11, an analog / digital converter 13 (A / D) connected to the output of the amplifier 12, a microcontroller 14 connected to the output of the analog / digital converter 13 and controlling the amplifier 12 so as to be able to adjust the gain of said amplifier, and an interface 15 connecting the microcontroller 14 to the bus link 5 or to any other link connecting the sensor 4 to the local central monitoring station 6.

As shown in Figure 3, the housing 9 of the sensor 4 can for example be a substantially parallelepipedal housing made of molded plastic, this housing comprising on one of its faces a wedge 16 substantially U-shaped, which defines a groove 17 adapted to engage partially on the corresponding neon tube 3. In the example shown, the transparent window 10 consists of an orifice pierced in the bottom of the groove 17 and covered by a transparent film 18 ensuring the sealing of the housing.

In addition, in the example shown in FIG. 3, the housing 9 of the sensor 4 advantageously comprises two encoder wheels 5a making it possible to determine the electronic address of the sensor 4 in the bus 5, so as to allow communication between the sensor 4 and the local central monitoring station 6.

As shown in FIG. 4, the local central monitoring station 6 may for example include a programmable controller 19 integrated in a protection cabinet 6a.

The controller 19 can be connected for example:

- to a modem 20 itself connected to the aforementioned telecommunications link 7, to a mains supply 21 which also allows the controller 19 to measure the supply voltage, which supply voltage is also supplied to the light elements 3 via power supply modules 27 (P),

- to a temperature sensor 22 measuring the ambient temperature, to a back-up battery 23,

- to an intrusion sensor 24 making it possible to detect the presence of a person on the roof of the building 2, or more generally in the vicinity of the light display device 1 when said light display device is located in a closed place at public, the intrusion sensor 24 being able to be constituted for example by a contact sensor (C1) adapted to detect the opening of a door or an access hatch to the roof of the building 2, to a sensor 25, in particular a contact sensor (C2), suitable for detecting the opening of the protection cabinet 6a, to an emergency cut-off system 26 connected to the power supply module 27 to cut the power supply to the device. illuminated display 1 in the event of an emergency, where applicable, to a keypad 28 and a screen 29,

- and to the bus link 5 which is connected to the various light sensors 4 (SENS.) and, where appropriate, to the aforementioned power supply modules 27 (these power supply modules 27 could possibly be connected to the PLC programmable 19 via another link than the bus link 5, for example an I2C type bus link).

The telesurveillance system which has just been described operates as follows.

During the installation of the system, the gain of the amplifier 12 of each sensor 4 is configured, via the automaton 19, so that all the sensors 4 emit substantially the same signal. The gains of the amplifiers 12 of the sensors 4 are thus configured and are therefore different according to the light elements 3, and in particular according to the color of these light elements.

In addition, curves or correction tables are stored in the programmable controller 19 which compensate for the drift in the light intensity emitted by the light elements 3 as a function of the ambient temperature and as a function of the supply voltage. These correction tables or curves thus allow the programmable logic controller 19 to correct the measurements of light intensity that it receives from the sensors 4, so as to different display histories to determine corrected measurements equivalent to standard temperature conditions and supply voltage (for example, ambient temperature of 10 ° C and supply voltage of 220V).

The aforementioned curves or correction tables may optionally be different depending on the types of light elements 3, and in particular according to the color of the light elements.

During the periods of operation of the light display device 1, the programmable controller 19 regularly interrogates the various light sensors 4 and stores the light intensity measurements coming from these sensors, after correction.

In addition, at regular intervals, for example once a day, the programmable controller 19 comes into contact with the central station 8 via the communication link 7 and sends it the corrected measurements thus stored.

In this way, the central station 8 has one of the corrected light intensities of the light elements 3 of each device that it monitors, which makes it possible to detect, manually or automatically, the light elements 3 which undergo a drop in light intensity. indicating that said light elements are reaching the end of their life. It is then possible to initiate a preventive maintenance operation and to replace the aging light elements 3 before they fail.

Furthermore, the programmable controller 19 is advantageously suitable for immediately signaling to the central station 8:

the presence of a person in the vicinity of the display device 1, detected by the sensor 24, the opening of the protection cabinet 6a, detected by the sensor 25,

- and the emergency cut-off of the power supply to the display device 1, detected from the emergency cut-off system 26.

It will also be noted that the correction of the light intensity measurements could, if necessary, be carried out inside each sensor 4, by memorizing the curves or microcontroller tables 14 of the sensor, then adjusts the gain of the amplifier accordingly. 12 of said sensor.

correction in which microcontroller