Touch sensor back plane ground connection

• US 8,337,216 B1
• Filed: 07/26/2011
• Issued: 12/25/2012
• Est. Priority Date: 07/26/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Miller, Thayne M.
• Primary Examiner(s): Johnson, Amy C.
• Assistant Examiner(s): Imas, Vladimir
• Application Number:
  US13/191,368
• Time in Patent Office: 518 Days
• Field of Search: 439/65, 439/67, 178 1801- 1811, 345173-178
• US Class Current: 439/67
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: H01R 4/06 Riveted connections by explosion H01R4/08

Abstract

Touch sensor panels can use touch sensors to detect the presence and location of a touch event. In order for the touch sensors to function reliably, the back plane of the touch sensor panel should be grounded. Supplying this ground connection can provide a uniform electrical reference point from which changes in voltage and capacitance due to a touch event can be measured. Without this ground connection, touch sensors may misrepresent the touch event. Various embodiments of the present disclosure provide different means for providing a ground connection for the back plane of a touch sensor panel. These embodiments are designed to provide a reliable ground connection even in the presence of various failure conditions.

Claims

1. A flexible tail configured to electrically connect a first component of a touch sensor panel to a second component of the touch sensor panel, the flexible tail comprising:

a non-critical bend adjacent to a connection point between the flexible tail and the second component;

a non-conductive side; and

a conductive side in contact with the second component,

wherein the flexible tail is configured to be fastened to the second component by inserting a screw through a hole in the flexible tail, and

wherein the flexible tail is positioned to maintain electrical connectivity between the first component and the second component if the flexible tail cracks along the non-critical bend.

2. The flexible tail of claim 1, wherein the flexible tail is positioned by placing a first portion of the conductive side against the first component and a second portion of the conductive side against the second component, a transition from the first portion to the second portion having no bends.

3. The flexible tail of claim 2, wherein the flexible tail is further positioned by bending a third portion of the flexible tail over itself at the non-critical bend such that the conductive side lies underneath a head of the screw.

4. The flexible tail of claim 2, wherein the positioned flexible tail is configured to maintain electrical connectivity between the first component and the second component through the flexible tail'"'"'s conductive side if the flexible tail cracks along the non-critical bend or if corrosion forms between a head of the screw and the flexible tail.

5. The flexible tail of claim 3, wherein the positioned flexible tail is configured to maintain electrical connectivity between the first component and the second component through the screw if corrosion forms between the flexible tail and the second component.

6. The flexible tail of claim 1, wherein the flexible tail is positioned by placing a first portion of the non-conductive side against the first component and bending a second portion of the flexible tail underneath itself at the non-critical bend such that the conductive side of the flexible tail lies against the second component.

7. The flexible tail of claim 6, wherein the positioned flexible tail is configured to maintain electrical connectivity between the first component and the second component through the screw if the flexible tail cracks along the non-critical bend or if corrosion forms between the flexible tail and the second component.

8. The flexible tail of claim 1, wherein the second component is electrically connected to earth ground.

9. The flexible tail of claim 1, wherein the conductive side is made from aluminum or copper and the non-conductive side is made from PET or plastic.

10. The flexible tail of claim 1, wherein the flexible tail has a critical bend at a connection point between the flexible tail and the first component.

11. The flexible tail of claim 1, wherein a washer is placed between the conductive side of the flexible tail and a head of the screw.

12. The flexible tail of claim 1, wherein the first component is a back plane of the touch sensor panel and the second component is a body of the touch sensor panel.

13. A flexible tail configured to electrically connect a first component of a touch sensor panel to a second component of the touch sensor panel, the flexible tail comprising:

a non-conductive side; and

a conductive side in contact with the second component,

wherein the flexible tail is positioned to maintain electrical connectivity between the first component and the second component if corrosion forms between the flexible tail and a head of a screw.

14. The flexible tail of claim 13, wherein the flexible tail is positioned by placing a first portion of the conductive side against the first component and a second portion of the conductive side against the second component, a transition from the first portion to the second portion having no folds.

15. The flexible tail of claim 13, wherein the flexible tail is free of non-critical bends.

16. The flexible tail of claim 13, wherein the first component is a back plane of the touch sensor panel and the second component is a body of the touch sensor panel.

17. A method for electrically connecting a first component of a touch sensor panel to a second component of the touch sensor panel, comprising:

forming a flexible tail, the flexible tail having

a non-critical bend adjacent to a connection point between the flexible tail and the second component,

a non-conductive side, and

a conductive side in contact with the second component;

fastening the flexible tail to the second component by inserting a screw through a hole in the flexible tail; and

positioning the flexible tail to maintain electrical connectivity between the first component and the second component if the flexible tail cracks along the non-critical bend.

18. The method of claim 17, wherein positioning the flexible tail comprises placing a first portion of the conductive side against the first component and a second portion of the conductive side against the second component, the transition from the first portion to the second portion having no bends.

19. The method of claim 18, wherein positioning the flexible tail further comprises bending a third portion of the flexible tail over itself at the non-critical bend such that the conductive side lies underneath a head of the screw.

20. The method of claim 17, wherein positioning the flexible tail comprises placing a first portion of the non-conductive side against the first component and bending a second portion of the flexible tail underneath itself at the non-critical bend such that the conductive side of the flexible tail lies against the second component.

21. The method of claim 17, wherein the first component is a back plane of the touch sensor panel and the second component is a body of the touch sensor panel.

22. A method for electrically connecting a first component of a touch sensor panel to a second component of the touch sensor panel, comprising:

forming a flexible tail, the flexible tail having

a non-conductive side, and

a conductive side in contact with the second component; and

positioning the flexible tail to maintain electrical connectivity between the first component and the second component if corrosion forms between the flexible tail and a head of a screw.

23. The method of claim 22, wherein positioning the flexible tail includes placing a first portion of the conductive side of the flexible tail against the first component and a second portion of the conductive side of the flexible tail against the second component, the transition from the first portion to the second portion having no folds.

24. The method of claim 23, wherein the first component is a back plane of the touch sensor panel and the second component is a body of the touch sensor panel.