Touch sensor system

• US 8,324,910 B2
• Filed: 03/04/2009
• Issued: 12/04/2012
• Est. Priority Date: 12/17/2004
• Status: Active Grant

• Current Assignee: Stoneridge Control Devices, Inc. (Stoneridge Incorporated)
• Original Assignee: Stoneridge Control Devices, Inc. (Stoneridge Incorporated)
• Inventors: Lamborghini, Louis R., Yuen, Benjamin K., Babington, Thomas E.
• Primary Examiner(s): NGUYEN, HOAI AN D
• Application Number:
  US12/397,605
• Publication Number:
  US 20090160529A1
• Time in Patent Office: 1,371 Days
• Field of Search: 324/713, 324/649, 324/600, 324/679, 324/658, 324/691, 323/904, 327/517, 345/173, 348/14.03, 379/93.19, 399/185, 463/37
• US Class Current: 324/658
• CPC Class Codes: B60K 2360/1446 Touch switches
• CPC Class Codes: B60K 2360/34 Backlit symbols
• CPC Class Codes: B60K 35/10 Input arrangements, i.e. from user to vehicle, associated with vehicle functions or specially adapted therefor
• CPC Class Codes: H03K 17/96 Touch switches specially adapted for electronic time-pieces with no moving parts G04G21/08
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2017/9602 characterised by the type or shape of the sensing electrodes
• CPC Class Codes: H03K 2017/9606 using one electrode only per touch switch
• CPC Class Codes: H03K 2217/94052 with evaluation of actuation pattern or sequence, e.g. tapping
• CPC Class Codes: H03K 2217/96015 Constructional details for touch switches for capacitive touch switches see H03K2217/9607
• CPC Class Codes: H03K 2217/96042 with illumination
• CPC Class Codes: H03K 2217/960725 Charge-transfer

Abstract

A touch sensor assembly. The touch sensor assembly may include a housing, at least one touch sensor and a sensor cover. The sensor cover may identify a touch area associated with each touch sensor. The housing may form a water tight cavity for the sensor cover and the touch sensor when coupled to an housing cover. A raised dome may be provided, e.g. on the sensor cover or another element, to provided tactile feed back. LEDs may be provided for illuminating the touch areas and/or sensing ambient light. A controller may control the illumination level of the LEDs in response to sensed ambient light. Adjacent key suppression algorithms are also provided.

Claims

1. A touch sensor assembly comprising:

a housing;

a circuit board configured to be received at least partially in said housing;

at least one light emitting diode (LED) coupled to said circuit board;

at least one touch sensor coupled to said circuit board; and

a sensor cover configured to be received at least partially in said housing with said circuit board disposed between said housing and said sensor cover, said sensor cover comprising a graphical indicator of a touch area associated with said at least one touch sensor,

said housing comprising a mating feature configured to mate with a corresponding feature on a rear surface of an housing cover to provide a substantially water tight cavity for enclosing said circuit board and said sensor cover between said housing and said housing cover,

said housing cover comprising a translucent material configured to obscure said graphical indicator so that it is not readily visible unless said LED is illuminated.

2. The touch sensor assembly of claim 1, wherein said mating feature comprises a slot extending about a perimeter of said housing, and wherein said corresponding feature of said housing cover comprises a projection, said slot configured to accept said projection to provide said substantially water tight cavity.

3. The touch sensor assembly of claim 2, wherein said projection comprises an upstanding wall defining a closed geometry.

4. The touch sensor assembly of claim 2, wherein an adhesive is at least partially disposed within said slot.

5. The touch sensor assembly of claim 1, wherein said at least one light emitting diode (LED) is mounted to a bottom surface of said circuit board and configured for illuminating said touch area.

6. The touch sensor assembly of claim 1, said assembly comprising a plurality of said touch sensors coupled to said circuit board, and a plurality of said graphical indicators, each of said graphical indicators being associated with one of said touch sensors, said assembly further comprising a plurality of said light emitting diodes (LEDs) , each of said LEDs being mounted to said bottom surface of said circuit board, each of said LEDs being configured for illuminating an associated one of said touch areas.

7. The touch sensor assembly of claim 1, wherein said graphical indicator is provided on a raised dome portion of said sensor cover, said raised dome portion being positioned to be disposed over said touch sensor upon assembly of said circuit board and said sensor cover to said housing.

8. The touch sensor assembly of claim 1, wherein said touch sensor comprises capacitive circuitry configured to exhibit a capacitance responsive to contact with said touch area.

9. The touch sensor assembly of claim 1,

wherein said touch sensor comprises a variable capacitance that changes in response to contact with said touch area to establish an associated output voltage to be used by a controller for determining if said touch area has been touched by a user;

and

a raised dome portion positioned over said touch area, said raised dome portion being configured to deform into contact with said touch sensor upon application of a force to said raised dome portion toward said touch sensor and being configured to return to a non-deformed state when said force is removed,

said raised dome having height above said touch sensor in said non-deformed state great enough so that said touch sensor will not provide said output unless said raised dome is deformed into said deformed state by said force.

10. The touch sensor assembly of claim 1, wherein said at least one touch sensor comprises variable capacitance that changes in response to contact with a touch area to establish an associated output voltage to be used by a controller for determining if said touch area has been touched by a user.

11. The touch sensor assembly of claim 1, said assembly further comprising:

at least one conductor coupling said sensor cover to said touch sensor.

12. The touch sensor assembly of claim 11, said sensor cover having a bottom surface spaced a distance from an illuminating surface of said LED, said distance selected to provide a desired illumination coverage area by said LED on said touch area.

13. The touch sensor of claim 12, wherein said touch sensor is coupled to said circuit board, and wherein said LED is coupled to a bottom surface of said circuit board.

14. The touch sensor assembly of claim 1, said assembly further comprising:

a controller,

wherein said light emitting diode (LED) is configured to illuminate at least a portion of said touch area and to sense an ambient light level adjacent said touch area, said controller configured to control an illumination level provided by said LED in response to said sensed ambient light level.

15. The touch sensor assembly of claim 14, wherein said illumination level provided by said LED is at a first illumination level for a first ambient light level and at a second illumination level for a second ambient light level, said first ambient light level greater than said second ambient light level, and said first illumination level greater than said second illumination level.

16. The touch sensor assembly of claim 14, wherein said LED is coupled to a bottom surface of said circuit board.

17. The touch sensor assembly of claim 9, further comprising a reference electrode disposed adjacent said at least one touch sensor.

18. The touch sensor assembly of claim 14, further comprising a reference electrode disposed adjacent said touch sensor, configured to prevent said output based on a signal from said electrode.