Classifications

• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
  • H03K17/96—Touch switches
  • H03K17/9625—Touch switches using a force resistance transducer
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
  • H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
  • H03K2217/96—Touch switches
  • H03K2217/96015—Constructional details for touch switches

Definitions

• the present invention relates to an electrical control device by tactile surface using pressure sensitive resistors (also known as FSR sensor for "Force Sensing Resistor” in English), particularly for control devices of motor vehicles such as a motorized mechanism for opening and / or closing at least one opening or an electronic element for a multimedia screen or an air conditioning system. More recently, it has been proposed to use, for these commands, tactile surfaces making it possible to detect a simple support of the finger to trigger a particular type of action or control, such as for a vehicle member control, as a function of the position of the detected support and / or the subsequent displacement of this support on the surface. These touch surfaces are increasingly using the technology of pressure-sensitive resistors, which outpace other equivalent technologies, such as capacitive or optical technologies, thanks to its ease of implementation and its robustness.
• Such sensors are for example known under the name “digitizing tablet” (English name “Digitizer pad”) and are cited as prior art the following documents: US 4,810,992, US 5,008,497, FR 2683649 or EP 0 541 102.
• These sensors comprise semiconductor layers sandwiched between, for example, a conductive layer and a resistive layer.
• a pressure on the FSR layer By exerting a pressure on the FSR layer, its ohmic resistance decreases, thus making it possible, by application of a suitable voltage, to measure the applied pressure and / or the location of the place where the pressure is exerted.
• the bottom surface of the sensor can be fixed by gluing on a support provided for this purpose.
• this joining technique can cause problems.
• partial detachment of the sensor can be observed for significant variations in the temperature fluctuating between -40 ° C. and 85 ° C.
• the object of the present invention is therefore to provide an electrical control device having a better behavior in the face of variations in the outside temperature.
• the subject of the invention is a tactile surface control device comprising a sensor whose surface is sensitive to a variation in tactile pressure and a support carrying the sensor, characterized in that the sensor is mounted floating on the support. and in that the support comprises positioning means cooperating with a dead zone of the sensor for positioning the sensor on the support.
• FIG. 1 is a perspective view of the control device according to a first embodiment of the invention
• FIG. 2 is a perspective view of the control device according to a second embodiment of the invention
• FIG. 3 is a perspective view of the control device according to a third embodiment of the invention.
• the identical elements bear the same reference numbers.
• FIG. 1 shows a control device 1 according to the invention, for example suitable for controlling a motorized mechanism (not shown) for opening and / or closing an opening, such as for example a window of a motor vehicle, a sunroof or the boot / tailgate / motorized sliding door of a vehicle.
• a motorized mechanism for opening and / or closing an opening
• this type of device can be adapted to any other electrical control of a motor vehicle such as an electric seat control or light controls such as a ceiling lamp or ambient lighting.
• the electrical control device with a tactile surface 1 comprises a sensor 3 carried by a support 5 in particular intended to be covered with a protective coating and assembled with a printed circuit board, in a not shown housing.
• the support 5 made of plastic for example, comprises, in particular, snap-fitting means 6 to the casing as well as lateral notches 8 allowing the passage of screws for fixing a cover and a bottom that fits together. in the other to form the housing (not shown).
• the sensor 3 has a sensitive surface 7 to a variation of tactile pressure (also known as FSR sensor for "Force Sensing Resistor” in English), that is to say using pressure sensitive resistors.
• tactile pressure also known as FSR sensor for "Force Sensing Resistor” in English
• These sensors comprise flexible semiconductor layers sandwiched between, for example, a conductive layer and a resistive layer. By exerting pressure or sliding on the FSR layer, its ohmic resistance decreases allowing, by applying a suitable voltage, to measure the pressure applied and / or the location of the place where the pressure is exerted.
• the touch sensor comprises two flexible support sheets spaced from each other by elastic spacers and on mutually opposite faces of the elements making it possible to make an electrical contact during the compression. of the sensor.
• the sensitive surface 7 comprises three adjacent active zones 7a, 7b, 7c corresponding to the active zones for controlling a specific electrical function in these zones.
• the tactile surface 7 comprises two inactive transverse regions 9a and 9b, and a peripheral region 11, composed of the lateral regions 11a to Hd, also called dead zones.
• the transverse dead zones 9a and 9b are traversed by passages
• the touch surface 7 of the sensor 3 comprises connecting means 15 at its end, to provide the electrical connection with, for example, the printed circuit board (not shown).
• the connection means 15 are flexible.
• the connection means 15 are formed by an extension of the sensor 3.
• the senor 3 is mounted floating on the support 5 and the support 5 comprises a positioning means 17 cooperating with a dead zone 11 of the sensor 3 to position the sensor 3 on the support 5.
• the sensor 3 mounted floating on the support 5 makes it possible to overcome the problems related to the differences in thermal expansion coefficients between the sensor 3, the support 5 and the glue, which occur in the devices of the prior art. Indeed, the sensor 3 can move slightly sliding on its support 5 when the control device 1 is subject to significant thermal variations.
• the positioning means is essential to ensure that the location of the active area of the surface 7 of the sensor 3 corresponds to the location of the specific command requested by the user.
• the device 1 solves the problems of the prior art related to the fixing means of the sensor 3 to the support 5 by gluing.
• the positioning means 17 cooperates with a dead zone 11 of the sensor 3, which makes it possible to optimize the space requirement of the control device 1 while avoiding a loss of the active surface 7 of the sensor 3.
• the senor 3 is removably positioned at the support 5, which makes it possible to change it or reposition it easily if necessary. It is expected that the surface 7 of the sensor 3 fits into the support 5.
• the surface 7 and the support 5 have a parallelepipedal shape and the positioning means 17 and the corresponding dead zones 11b and Hd are located on the opposite lateral edges of the longitudinal ends of the device 1, to better position the sensor 3 on the support 5.
• FIG. 1 illustrates a first embodiment of the device 1 in which the positioning means 17 comprises at least one centering pin 19 cooperating with at least one corresponding hole 21 formed in a dead zone 11 of the sensor 3.
• the hole 21 has an opening, for example circular, slightly larger than the section of the centering pin 19, so as to allow a slight sliding of the sensor 3 around the pin 19.
• the positioning means 17 of the device 1 comprises two centering pins 19 located on the opposite side edges of the support 5 which cooperate respectively with two corresponding holes 21 formed in a dead zone 11a, 11b of the sensor 3.
• a compact manufacturing unit comprising the sensor 3 assembled to the support 5, advantageously connected to a printed circuit board, which can be handled independently during the assembly phases of the manufacturing processes. It is also possible to use the lateral notches 8 of the support 5 as additional positioning means by providing corresponding cuts in the dead zones 11a, 11c of the sensor 3.
• the device 1 to comprise fastening means not shown in this figure, in order to removably fix the sensor 3 to the support 5.
• these fixing means are formed by the housing of the device 1, taking the sensor 3 sandwiched between the support 5 and the protective coating.
• the positioning means 17 comprise at least one holding hook 23 which cooperates with a peripheral dead zone 11 of the sensor 3.
• the senor 3 advantageously comprises a peripheral dead zone 11 around the active zone 7. whose lateral dimension is sufficient to allow its cooperation with the holding hook 23.
• the support comprises a raised peripheral edge 24 surrounding the sensor 3 in which the holding hooks 23 are formed.
• the border 24 and the holding hooks 23 form a positioning means 17 of the sensor 3 in the support 5 and the holding hooks 23 further allow the retention of the sensor 3 in the device 1.
• two holding hooks 23 cooperate with a peripheral dead zone Hd of the lateral face opposite to the electrical connection means 15 of the sensor 3.
• the flexible connection means 15 already form a positioning means on this face of the sensor 3.
• the device 1 also comprises at least one holding hook 23 cooperating with a peripheral dead zone Ha, Hc of each longitudinal face of the sensor 3.
• the positioning means 17 comprises at least one centering pin 25 cooperating with a corresponding hole 26 and at least one attachment tooth 27 cooperating with a corresponding oblong hole 28.
• the pin 25 and the hooking tooth 27 make it possible to position the sensor 3 on the support 5 and the hooking tooth 27 also makes it possible to retain the sensor 3 on the support 5.
• the oblong hole 28 allows the lateral positioning of the sensor 3 to the support 5, while allowing a slight longitudinal sliding of the sensor 3 around the attachment tooth 27.
• the centering pin 25 and the hooking tooth 27 are located on opposite edges of the support 5 and cooperate with corresponding holes 26 and 28 formed in corresponding dead zones Hb and Hd, opposite one another. other in the length of the sensor 3.

Landscapes

• Switches That Are Operated By Magnetic Or Electric Fields (AREA)
• Manipulator (AREA)
• Push-Button Switches (AREA)
• Adjustable Resistors (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=39386404

Family Applications (1)

Country Status (6)

Citations (1)

Family Cites Families (14)

• 2007
  • 2007-07-31 FR FR0705594A patent/FR2919737B1/fr active Active
• 2008
  • 2008-07-21 US US12/670,828 patent/US20100288568A1/en not_active Abandoned
  • 2008-07-21 JP JP2010518615A patent/JP5318868B2/ja active Active
  • 2008-07-21 EP EP08775238A patent/EP2174418A1/de not_active Withdrawn
  • 2008-07-21 WO PCT/EP2008/059510 patent/WO2009016058A1/fr active Application Filing
  • 2008-07-21 CN CN200880101322A patent/CN101772890A/zh active Pending

Patent Citations (1)

Non-Patent Citations (1)

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