Geared haptic feedback element

• US 9,779,592 B1
• Filed: 09/22/2014
• Issued: 10/03/2017
• Est. Priority Date: 09/26/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Hoen, Storrs T.
• Primary Examiner(s): Pope, Daryl
• Application Number:
  US14/493,190
• Time in Patent Office: 1,107 Days
• Field of Search: 3404071, 3405731, 345161
• CPC Class Codes: G08B 6/00 Tactile signalling systems, e.g. personal calling systems
• CPC Class Codes: H02K 21/185 with the axis of the rotor perpendicular to the plane of the armature
• CPC Class Codes: H02K 7/061 using rotary unbalanced masses for generating mechanical vibrations in general B06B1/16
• CPC Class Codes: H02K 7/116 with gears

Abstract

A thin haptic feedback element suitable to provide a perceivable single pulse haptic feedback including an electromagnetic coil, a permanent magnet or other magnetic field source rotatably coupled to an eccentric mass through a torque-increasing drive train. The haptic feedback element may rapidly accelerate and decelerate the eccentric mass to produce a perceivable haptic feedback.

Claims

1. A haptic feedback element comprising:

an electromagnetic coil having a core;

a magnetic field source rotatable about a first axis, the magnetic field source positioned proximate the core;

a first gear fixedly coupled to the magnetic field source;

a second gear rotatably coupled to the first gear, the second gear rotatable about a second axis; and

a mass element fixedly coupled to the second gear positioned eccentrically to the second axis;

wherein

a first angular displacement of the first gear causes a second angular displacement in the second gear.

2. The haptic feedback element of claim 1, wherein the first angular displacement is greater than one but less than ten times the second angular displacement.

3. The haptic feedback element of claim 1, wherein the first angular displacement is ten times or greater the second angular displacement.

4. The haptic feedback element of claim 1, wherein the electromagnetic coil operates in at least an operation mode and a brake mode.

5. The haptic feedback element of claim 4, wherein the operation mode comprises an alternating a magnetic field through the core.

6. The haptic feedback element of claim 4, wherein the brake mode comprises one of fixing a magnetic field through the electromagnetic coil, reversing a magnetic field through the electromagnetic coil, and alternating a magnetic field within the electromagnetic coil.

7. The haptic feedback element of claim 1, wherein the magnetic field source comprises a permanent magnet.

8. The haptic feedback element of claim 1, further comprising a third gear that rotatably couples the first gear to the second gear.

9. The haptic feedback element of claim 1, wherein the eccentric mass is metal.

10. A method of providing haptic feedback comprising:

receiving a request for haptic feedback;

providing current of a first polarity to an electromagnetic coil magnetically proximate a rotatable magnetic field source;

providing current of a second polarity to the electromagnetic coil; and

applying a braking current to the electromagnetic coil that causes an eccentric mass rotatably coupled to the rotatable magnetic field source to decelerate.

11. The method of claim 10, wherein the operations of providing a current of a first polarity and providing a current of a second polarity repeat a selected number of times prior to the operation of applying a braking current.

12. The method of claim 11, wherein the selected number of repetitions is determined based on an angle of rotation of the eccentric mass.

13. The method of claim 12, wherein the angle of rotation of the eccentric mass is one tenth of the angle of rotation of rotatable magnetic field source.

14. The method of claim 10, wherein the rotatable coupling between the rotatable magnetic field source and the eccentric mass comprises at least a first gear.

15. The method of claim 12, wherein the angle of rotation of the eccentric mass is determined at least in part by a magnetic field sensor.

16. The method of claim 12, wherein the angle of rotation of the eccentric mass is greater than one tenth of the angle of rotation of rotatable magnetic field source.

17. A haptic feedback element comprising:

a single-phase stepping motor with a drive axis;

a first gear fixedly coupled to the drive axis;

a second gear rotatably coupled to the first gear, the second gear rotatable about an axis of rotation;

a mass element fixedly coupled to the second gear positioned eccentrically to axis of rotation; and

a commutator configured to operate the single-phase stepping motor synchronously.

18. The haptic feedback element of claim 17, wherein a first angular displacement of the first gear causes a second angular displacement in the second gear.

19. The haptic feedback element of claim 18, wherein the first angular displacement is greater than one but less than ten times the second angular displacement.

20. The haptic feedback element of claim 17, wherein a first diameter of the first gear is less than a second diameter of the second gear.