Force-Sensitive Input Device

• US 20140078070A1
• Filed: 09/14/2012
• Published: 03/20/2014
• Est. Priority Date: 09/14/2012
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Armstrong-Muntner, Joel S.
• Granted Patent: US 9,639,179 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0441 using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals
• 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

Abstract

An input device for computing devices that include touch screens. The input device includes an outer housing having an inner surface and an inner shaft. The inner shaft is at least partially received within the outer housing. A nib is operatively coupled to the inner shaft. Providing a first force to the nib causes the inner shaft to contact the inner surface of the outer housing at a first contact point along the outer housing, and providing a second force to the nib causes the inner shaft to contact the inner surface of the outer housing at a second contact point along the outer housing.

Claims

1. An input device for computing devices comprising:

an outer housing having an inner surface;

an inner shaft at least partially received within the outer housing; and

a nib operatively coupled to the inner shaft;

wherein

providing a first force to the nib causes the inner shaft to contact the inner surface of the outer housing at a first contact point along the outer housing; and

providing a second force to the nib causes the inner shaft to contact the inner surface of the outer housing at a second contact point along the outer housing.

2. The input device of claim 1, wherein the inner shaft comprises an outer surface, and the outer surface of the inner shaft contacts the inner surface of the outer housing responsive to the first and second forces.

3. The input device of claim 1, wherein the outer surface of the inner shaft selectively forms an electrical connection at the first and second contact points of the outer housing.

4. The input device of claim 1, wherein the first force causes the inner shaft to bend at a first bend point along the inner shaft, the first bend point being coupled to the first contact point responsive to the first force.

5. The input device of claim 1, wherein the inner surface of the outer housing comprises a resistive element, the inner shaft comprises a conductive element, and wherein the input device further comprises a substantially constant source coupled to a first portion of the resistive element.

6. The input device of claim 5, wherein the inner shaft selectively contacts the resistive element at locations along the outer housing responsive to the first and second forces, and the input device selectively provides first and second measurements indicative of the respective first and second forces.

7. The input device of claim 6 wherein the substantially constant source comprises a current source and the measurements comprise voltages.

8. The input device of claim 5, wherein the substantially constant source comprises a voltage source, and a second portion of the resistive element is coupled to a reference voltage node.

9. The input device of claim 1, wherein the inner shaft comprises a resistive element.

10. The input device of claim 9, wherein a contact resistance of the resistive element increases along a first direction of the resistive element.

11. An apparatus comprising:

an inner shaft including an electrically conductive portion; and

a nib operatively coupled to the inner shaft and configured to bias the inner shaft in a first biasing direction within a rigid housing such that the electrically conductive portion of the inner shaft contacts the rigid housing at a first location along a longitudinal axis of the rigid housing.

12. The apparatus of claim 11, wherein at least a portion of the inner shaft is flexible.

13. The apparatus of claim 12, wherein the nib is configured to bias the flexible inner shaft in the first biasing direction responsive to a first force, and the nib is further configured to bias the flexible inner shaft in a second biasing direction responsive to a second force greater than the first force such that the electrically conductive portion contacts the rigid housing at a second location along the longitudinal axis of the rigid housing.

14. The apparatus of claim 11, wherein the inner shaft comprises an outer surface, and the outer surface comprises the electrically conductive portion.

15. The apparatus of claim 11, wherein the inner shaft comprises a depth plunger.

16. The apparatus of claim 11, wherein the inner shaft comprises a plurality of disks and a plurality of resistances coupled between the plurality of disks, and at least one of the plurality of disks comprises the electrically conductive portion.

17. A stylus for providing an input to a touch interface of a computing device, comprising:

an elongated body;

a nib operably coupled to the elongated body; and

an inner shaft operably coupled to the nib and at least partially received within the elongated body;

wherein

movement of the nib causes a portion of the inner shaft to bend towards the elongated body.

18. The stylus of claim 17, wherein the portion of the inner shaft makes an electrical contact with the elongated body responsive to the movement of the nib, and further wherein the stylus is configured to provide a signal indicative of a location of the electrical contact along the elongated body.

19. The stylus of claim 17, wherein the movement of the nib is radial movement relative to the elongated body.

20. The stylus of claim 17, wherein the nib is electrically coupled to an outer surface of the elongated body and the stylus is configured for use with a capacitive touch interface.

21. A method for operating an input device for a computing device, comprising:

determining a contact position of an inner shaft with an outer housing, the contact position of the inner shaft with the outer housing varying responsive to a force provided to the nib; and

providing an output signal responsive to the determined contact position.

22. The method of claim 21, further comprising monitoring the contact position of the inner shaft with the outer housing and providing the output signal responsive to the monitored contact position.

23. The method of claim 21, wherein the output signal provided responsive to the determined contact position increases in magnitude as the force applied to the nib increases.

24. The method of claim 21, further comprising transmitting the output signal to the computing device.

25. The method of claim 21, wherein the contact position of the inner shaft with the outer housing is determined by voltage dividing a voltage applied to the outer housing through a wiper, the wiper comprising the inner shaft.

26. The method of claim 21, further comprising determining an orientation of the input device relative to the computing device and transmitting the orientation to the computing device.