Force sensor for use in an input device and methods for constructing and using the sensor

• US 8,446,360 B2
• Filed: 01/14/2009
• Issued: 05/21/2013
• Est. Priority Date: 09/30/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Baskett, Lawrence Jared, Amm, David Thomas
• Primary Examiner(s): Boddie, William L
• Assistant Examiner(s): Edwards, Carolyn R
• Application Number:
  US12/353,732
• Publication Number:
  US 20100082270A1
• Time in Patent Office: 1,588 Days
• Field of Search: 345156-175, 178/18.03, 178/18.06, 702/41, 702/190, 738/626.32
• US Class Current: 345/156
• CPC Class Codes: G01L 5/165 using variations in capacitance
• CPC Class Codes: G01L 5/223 to joystick controls
• CPC Class Codes: G06F 3/03543 Mice or pucks G06F3/03541 takes precedence

Abstract

The disclosure addresses a force sensor that is scalable in size and adaptable to a variety of form factors, including those suitable for use in an input device for a computer or other processing system, and in some cases including those of the configuration normally referred to as a computer mouse. The force sensor will include at least two structural members that are cooperatively attached one another as to be displaced from one another in response to a force acting upon one of the structural members. In some examples, the engagement between the two structural members will be specifically configured to allow such displacement in response to forces acting laterally on the force sensor. The force sensor will also include one or more sensing mechanisms to provide a measurement of the sensed deflection.

Claims

1. A force sensor configured for use in an input device to a processing system, comprising:

a first support member;

a second support member coupled in movable relation to the first support member along at least a first axis;

a third support member coupled in movable relation to the second support member along at least a second axis orthogonal to the first axis;

a first sensor arranged to provide a first signal reflective of the degree of movement between the first and second support members relative to at least the first axis; and

a second sensor arranged to provide a second signal reflective of the degree of movement between the second and third support members relative to at least the second axis;

wherein the first and second support members are coupled in movable relation through a first flexure assembly extending between the first support member and the second support member;

further comprising;

a second flexure assembly; and

a third flexure assembly extending between the first support member and the second support member, the third flexure assembly in spaced relation to the first flexure assembly; and

wherein the first and third flexure assemblies each comprise a generally planar flex element, and

wherein the two flex elements extend in generally parallel planes to one another.

2. The force sensor of claim 1, wherein the second and third support members are coupled in movable relation through the second flexure assembly extending between the second support member and the third support member.

3. The force sensor of claim 1, wherein the first flexure assembly extending between the first and second support members comprises a flexible metal plate extending in a plane generally perpendicular to the first axis.

4. The force sensor of claim 1, wherein the input device comprises a hand-operated input device.

5. The force sensor of claim 1, wherein the input device comprises a computer mouse.

6. The force sensor of claim 1, wherein at least one of the first flexure assembly, the second flexure assembly, or the third flexure assembly comprises a flexible elastomer.

7. The force sensor of claim 6, wherein the flexible elastomer comprises a silicon-based elastomer.

8. The force sensor of claim 1, wherein at least one of the first flexure assembly, the second flexure assembly, or the third flexure assembly comprises a flexible metal.

9. The force sensor of claim 1, wherein at least one of the first flexure assembly, the second flexure assembly, or the third flexure assembly comprises a flexible plastic.

10. The force sensor of claim 1, wherein at least one of the first support member, the second support member, or the third support member comprises a rigid metal.

11. The force sensor of claim 1, wherein at least one of the first support member, the second support member, or the third support member comprises a rigid glass-filled plastic.

12. An input device, comprising:

a first support wing including, a first central web portion, and angled arms extending generally in a first direction relative to the central web portion;

a second support wing including, a second central web portion, a first pair of angled arms extending generally in a second direction relative to the central web portion, the second direction generally opposite to the first direction; and

a second pair of angled arms extending in generally the first direction relative to the central web portion, the second pair of angled arms extending generally orthogonally to the first pair of arms;

front and rear flex plates coupling the first and second support wings to one another through the angled arms,

the front and rear flex plates extending in spaced, generally parallel, relation to one another,

wherein the support wing having the lowermost web portion has its angled arms coupled to the relatively upper end of each flex plate, and

wherein the support wing having the uppermost web portion has its angled arms coupled to the relatively lower end of each flex plate;

a third support wing having a third central web portion, and angled arms extending generally in the second direction relative to the central web portion;

left and right flex plates coupling the second and third support wings to one another through the angled arms, the left and right flex plates extending in spaced, generally parallel, relation to one another,

wherein the support wing having the lowermost web portion has its angled arms coupled to the relatively upper end of each flex plate, and

wherein the support wing having the uppermost web portion has its angled arms coupled to the relatively lower end of each flex plate;

a first sensor assembly having a first component supported by the first support wing and a second component carried by the second support wing, and configured to provide a first signal reflective of the degree of movement between the first and second support wings relative to at least the first axis; and

a second sensor assembly having a first component supported by the second support wing and a second component carried by the third support wing, and configured to provide a first signal reflective of the degree of movement between the second and third support wings relative to at least the second axis.

13. The input device of claim 12, wherein the input device comprises a computer mouse.

14. The input device of claim 12, wherein the input device comprises a hand-operated input device.

15. The input device of claim 12, wherein at least one of the front and rear flex plates or the left and right flex plates comprise a flexible elastomer.

16. The input device of claim 15, wherein the flexible elastomer comprises a silicon-based elastomer.

17. The input device of claim 12, wherein at least one of the first the front and rear flex plates or the left and right flex plates comprise a flexible metal.

18. The input device of claim 12, wherein at least one of the first the front and rear flex plates or the left and right flex plates comprise a flexible plastic.

19. The input device of claim 12, wherein at least one of the first support wing or the second support wing comprises a rigid glass-filled plastic.

20. The input device of claim 12, wherein at least one of the first support wing or the second support wing comprises a rigid metal.