Integrated feature for friction-less movement of force sensitive touch screen

• US 8,780,543 B2
• Filed: 03/21/2012
• Issued: 07/15/2014
• Est. Priority Date: 03/15/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: F-Origin, Inc.
• Inventors: Mlne, Anders L., Griffith, David, Lackey, Mark, Noble, Curtiss
• Primary Examiner(s): Wilson, Adrian S
• Application Number:
  US13/425,846
• Publication Number:
  US 20120200789A1
• Time in Patent Office: 846 Days
• Field of Search: 361/679.21, 345/173, 349 58- 60
• US Class Current: 361/679.21
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G06F 1/1656 Details related to functional adaptations of the enclosure, e.g. to provide protection against EMI, shock, water, or to host detachable peripherals like a mouse or removable expansions units like PCMCIA cards, or to provide access to internal components for maintenance or to removable storage supports like CDs or DVDs, or to mechanically mount accessories mounting of accessories to a computer display G06F1/1607; display hoods G06F1/1603; cooling arrangements for portable computers G06F1/203
• CPC Class Codes: G06F 3/04142 the force sensing means being located peripherally, e.g. disposed at the corners or at the side of a touch sensing plate

Abstract

A suspension system for a differential-pressure touch sensitive panel suspended over force sensors, for use in either fixed or mobile devices such as point of sales terminals, kiosks, laptops, monitors, PDAs, cell phones, UMPCs and more. In one embodiment, a number of leaf springs are attached directly to the touch lens at both ends and attached directly to the underlying housing at the center, effectively pulling the leaf spring down at the center into a concave arc. The spring bias preloads the touch lens downward against the force sensors. The leaf springs bring the touch lens into a fixed state in the xy-plane and resist translation; however, the touch lens remains free to float against the bias of the leaf spring(s) without any frictional physical contact along the z-axis.

Claims

1. A suspension for a touch screen display having a touch panel parallely-spaced from a fixed base panel, and a plurality of force sensors there between supported by said fixed based panel in a bearing relation to said touch panel, comprising:

at least one elongate resilient leaf spring arm having a shape memory characteristic, said leaf spring arm being attached at both ends to one of said touch panel or base panel, and a center of said leaf spring-arm being attached to the other of said touch panel or base panel in an arcuate configuration, thereby pre-biasing said touch panel against said plurality of force sensors.

2. The suspension for a touch screen according to claim 1, wherein said at least one elongate resilient leaf spring arm comprises two elongate resilient leaf spring arms.

3. The suspension for a touch screen according to claim 2, wherein said at least one elongate resilient leaf spring arm comprises four elongate resilient leaf spring arms.

4. The suspension for a touch screen according to claim 1, wherein the center of said leaf spring-arm is attached to the base panel by an adjustable set screw.

5. The suspension for a touch screen according to claim 4, wherein the opposing ends of said leaf spring-arm are attached to the touch panel by fixed rivets.

6. The suspension for a touch screen according to claim 1, wherein the leaf spring-arm is cold-formed from spring steel with said shape memory characteristic.

7. The suspension for a touch screen according to claim 6, wherein the leaf spring-arm is cold-formed in a flat configuration from spring steel to provide said shape memory characteristic when deflected into an arched configuration.

8. The suspension for a touch screen according to claim 2, wherein the leaf spring-arms provide frictionless translation ability for said touch lens along a z-axis, while constraining relative lateral movement along an x-y plane.

9. The suspension for a touch screen according to claim 2, wherein said two elongate resilient leaf spring arm comprise plastic leaf spring arms.

10. A touch screen assembly for an electronic device, comprising:

a touch lens having an underside;

an LCD display parallely-spaced from said touch lens;

a supporting substrate underlying said LCD display;

a plurality of force sensors supported by said supporting substrate and bearing against the underside of said touch lens;

at least two elongate resilient leaf spring arms having a shape memory characteristic, each of said leaf spring arms being attached at both ends to one side of said touch lens, and a center of said leaf spring-arm being attached to said supporting substrate so as to maintain each of said leaf spring arms in an arcuate configuration, thereby pre-biasing said touch panel against said plurality of force sensors.

11. The touch screen assembly for an electronic device according to claim 10, wherein said at least one elongate resilient leaf spring arm comprises four elongate resilient leaf spring arms.

12. The touch screen assembly for an electronic device according to claim 10, wherein the center of each leaf spring-arm is attached to the supporting substrate by an adjustable set screw.

13. The touch screen assembly for an electronic device according to claim 10, wherein said at least two elongate resilient leaf spring arms comprise four elongate resilient leaf spring arms.

14. The touch screen assembly for an electronic device according to claim 10, wherein the opposing ends of said leaf spring-arms is attached to the touch lens by fixed rivets.

15. The touch screen assembly for an electronic device according to claim 10, wherein each leaf spring-arm is cold-formed from spring steel with said shape memory characteristic.

16. The suspension for a touch screen according to claim 15, wherein each said leaf spring-arm is cold-formed in a flat configuration from spring steel to provide said shape memory characteristic when deflected into an arched configuration.

17. The suspension for a touch screen according to claim 10, wherein said at least two leaf spring-arms provide frictionless translation ability for said touch lens along a z-axis, while constraining relative lateral movement along an x-y plane.

18. A suspension for a touch screen display having a touch lens and LCD display both seated in a rigid supporting structure, and a plurality of force sensors fixedly attached to said supporting structure in a bearing relation to said touch lens, comprising:

a pair of opposing elongate resilient leaf spring arms having a flat shape memory characteristic, both leaf spring arms being attached lengthwise along opposing edges of said touch lens and attached at both ends to said touch lens, and a center point of said leaf spring-arms being biased outward and attached to said rigid supporting structure in an arcuate configuration, the shape-memory characteristic thereby pre-biasing said touch panel against said plurality of force sensors.

19. The suspension for a touch screen according to claim 18, wherein the centers of both of said pair of leaf spring-arms are attached to the supporting structure by adjustable set screws to vary said pre-bias.

20. The suspension for a touch screen according to claim 19, wherein the opposing ends of both of said pair of leaf spring-arms are adhesively bonded to the touch lens.