Proximity switch having sensitivity control and method therefor

• US 8,928,336 B2
• Filed: 06/09/2011
• Issued: 01/06/2015
• Est. Priority Date: 06/09/2011
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Salter, Stuart C., Gardner, Cornel Lewis, Singer, Jeffrey, Whitens, Michael James
• Primary Examiner(s): Koval, Melissa
• Assistant Examiner(s): NGUYEN, TRUNG Q
• Application Number:
  US13/157,012
• Publication Number:
  US 20120313648A1
• Time in Patent Office: 1,307 Days
• Field of Search: 324/647, 324/600, 324682-688, 324/548, 324/661, 324/200, 324/207.13, 324219-246
• US Class Current: 324/647
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 2217/94026 Automatic threshold calibration; e.g. threshold automatically adapts to ambient conditions or follows variation of input
• CPC Class Codes: H03K 2217/960705 Safety of capacitive touch and proximity switches, e.g. increasing reliability, fail-safe

Abstract

A vehicle proximity switch and method are provided having sensitivity control based on a user selected sensitivity input. The switch includes a proximity sensor such, as a capacitive sensor, installed in a vehicle and providing a sense activation field. The proximity switch also includes control circuitry for processing the sense activation field to sense user activation of the switch by comparing the sense activation field to a threshold. The proximity switch further includes a user sensitivity input for receiving a user selected sensitivity input. The control circuitry controls sensitivity of the comparison based on the user selected sensitivity input.

Claims

1. A proximity switch having sensitivity control comprising:

a proximity sensor providing a sense activation field;

control circuitry processing the sense activation field to sense user activation of the switch by comparing the sense activation field to a threshold; and

a user sensitivity input for receiving a user selected sensitivity input, wherein the proximity sensor and the user sensitivity input each include capacitive plates or electrode pads which are formed as part of a capacitor and electronic circuitry, wherein electrical signals are applied to each of the proximity sensor and the user sensitivity input, and wherein the sensitivity of the proximity switch may be adjusted by changing a charge burst length of an electrical signal applied to the proximity sensor based on the user selected sensitivity input.

2. The proximity switch of claim 1, wherein the proximity switch is installed in a vehicle for use by a passenger in the vehicle.

3. The proximity switch of claim 1, wherein the proximity sensor comprises a capacitive sensor.

4. The proximity switch of claim 1, wherein the user sensitivity input comprises a capacitive switch.

5. The proximity switch of claim 1 further comprising an output for providing an output signal to control a device.

6. The proximity switch of claim 1, wherein the user sensitivity input comprises a dedicated user actuated switch.

7. The proximity switch of claim 1, wherein the user sensitivity input comprises one or more shared switches.

8. The proximity switch of claim 1, wherein the user sensitivity input is used to control sensitivity of a plurality of proximity switches.

9. A vehicle capacitive switch having sensitivity control comprising:

a capacitive sensor installed in a vehicle and providing a sense activation field;

control circuitry processing the sense activation field to sense user activation of the switch by comparing the sense activation field to a threshold; and

a user sensitivity input for receiving a user selected sensitivity input, wherein the capacitive sensor and user sensitivity input each include capacitive plates or electrode pads which are formed as part of a capacitor and electronic circuitry, wherein electrical signals are applied to each of the proximity sensor and the user sensitivity input, and wherein the sensitivity of the capacitive sensor may be adjusted by changing a charge burst length of an electrical signal applied to the capacitive sensor based on the user selected sensitivity input.

10. The capacitive switch of claim 9 further comprising an output for providing an output signal to control a device.

11. A method of sensing user proximity with adjustable sensitivity control, said method comprising;

providing a sense activation field with a proximity sensor;

processing the sensed activation field to sense user activation of the proximity sensor by comparing the sensed activation field to a threshold;

detecting a user sensitivity input, wherein the proximity sensor and the user sensitivity input each include capacitive plates or electrode pads which are formed as part of the capacitor and electronic circuitry, and wherein electrical signals are applied to each of the proximity sensor and the user sensitivity input; and

adjusting sensitivity of the comparison based on the user sensitivity input, whereon the sensitivity of the proximity sensor may be adjusted by changing a charge burst length of an electrical signal applied to the proximity sensor.

12. The method of claim 11, wherein the proximity sensor is installed in a vehicle for use by a passenger in the vehicle.

13. The method of claim 11, wherein the proximity sensor comprises a capacitive sensor.

14. The method of claim 11, wherein the step of detecting a user sensitivity input comprises sensing a user input with a dedicated sensitivity input.

15. The method of claim 11, wherein the step of detecting a user sensitivity input comprises sensing a user input with a shared input.

16. The method of claim 11 further comprising the step of outputting a control signal based on the comparison to control a device.