Input device roller with hybrid magnetic ratchet system

Abstract

A rotatable wheel for an input device which interfaces with a computer. The input device includes both a permanent magnet and an electromagnet. A rotor of material which will magnetically interact with the permanent magnet and electromagnet is coupled to the rotatable wheel. The permanent magnet and electromagnet can be used to control a ratchet force applied to the rotatable wheel. In an alternate embodiment, a rotatable wheel with a flywheel is engaged with a roller. A ratchet wheel can be intermittently engaged with the flywheel to provide a ratchet force. By disengaging the ratchet wheel, the flywheel can be allowed to spin, providing momentum to allow for easier scrolling in certain conditions, such as for scrolling through a long document.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the electronics of the tactile feedback according to one embodiment of the present invention.

FIG. 2 is a block diagram of the tactile feedback software according to an embodiment of the invention.

FIG. 3 is a diagram of a combined permanent magnet and electromagnet interacting with a rotor according to an embodiment of the invention.

FIG. 4 is a diagram illustrating the permanent magnet of FIG. 3 and its flux fields.

FIG. 5 is a diagram illustrating a combined flux field of the permanent and electromagnets.

FIG. 6 is a diagram illustrating the electromagnetic flux field canceling the permanent magnet flux field.

FIG. 7 is a diagram illustrating the direction of the magnetic fields of different points to produce the canceling effect.

FIG. 8 is a diagram of a simulation showing a Halbach array for canceling a magnetic field on one side and magnifying it on the other.

FIG. 9 is a diagram illustrating the permanent electromagnets of the invention interacting with a iron ratchet wheel connected by planetary gears to a scroll wheel.

FIG. 10 is a diagram of the embodiment of FIG. 9 showing the addition of a lead screw for controlling the permanent magnet distance to the ratchet wheel.

FIG. 11 is a diagram of a flywheel and ratchet wheel embodiment for controlling a scroll wheel ratchet.

FIG. 12 is a side view of the ratchet wheel and flywheel interaction of FIG. 11.

FIG. 13 is a diagram of the embodiment of FIG. 12 illustrating the long diameter position of the oval ratchet wheel against the flywheel.

FIG. 14 is a diagram of a side view illustrating the oval ratchet wheel being retracted by a solenoid.

FIG. 15 is a diagram of an embodiment of a metal ratchet wheel attached to an axle with an electromagnet.

FIG. 16 is a diagram of a electro-permanent magnet.

FIG. 17 is a diagram of an embodiment with a keeper in place to restrain the magnetic flux and avoid force on the wheel.—18 uses magnetic flux path adjustment.

FIG. 18 is a diagram of the embodiment of FIG. 17 with the keeper having been moved to allow magnetic flux to apply force to the wheel.

FIG. 19 is a simplified diagram of a DC motor 200 may be coupled to a roller wheel or may form a portion of a roller wheel of the control device.

Claims

1. A user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;a permanent magnet mounted in said device;an electromagnet mounted adjacent said permanent magnet; anda rotor made of a material which will magnetically interact with said permanent magnet and said electromagnet and coupled to said rotatable wheel and operative, in conjunction with at least one of said magnets, to provide a ratchet force to said rotatable wheel.

2. The device of claim 1 further comprising: a control circuit configured to energize said electromagnet to provide a combined magnetic field from said permanent magnet and said electromagnet which is larger than a magnetic field from said permanent magnet alone.

3. The device of claim 1 further comprising: a control circuit configured to energize said electromagnet to at least partially cancel a magnetic field from said permanent magnet alone.

4. The device of claim 1 further comprising an axle connecting said rotor to said wheel.

5. The device of claim 4 further comprising a planetary gear attached to and end of said axle, said planetary gear engaging a gear-toothed inside of said wheel.

6. The device of claim 1 further comprising a moveable member for adjusting a distance between said permanent magnet and said electromagnet.

7. The device of claim 6 wherein said moveable member is moveable via electric power.

8. The device of claim 1 further comprising a control circuit, responsive to a feedback signal from said host, for controlling an amount and direction of a magnetic field from said electromagnet to control and amount of ratcheting and a ratchet force.

9. user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;a permanent magnet mounted in said device;an electromagnet mounted adjacent said permanent magnet;a rotor made of a material which will magnetically interact with said permanent magnet and said electromagnet and coupled to said rotatable wheel and operative, in conjunction with at least one of said magnets, to provide a ratchet force to said rotatable wheel;an axle connecting said rotor to said wheel;a planetary gear attached to and end of said axle, said planetary gear engaging a gear-toothed inside of said wheel; anda control circuit configured to energize said electromagnet to provide a combined magnetic field from said permanent magnet and said electromagnet which is larger than a magnetic field from said permanent magnet alone;wherein said control circuit is further configured to energize said electromagnet to at least partially cancel a magnetic field from said permanent magnet.

10. A user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;a flywheel mounted in engagement with said rotatable wheel; anda ratchet wheel mounted for intermittent engagement with said flywheel.

11. The device of claim 10 wherein said flywheel is metal with a rubber tire mounted on its circumference.

12. The device of claim 10 wherein said ratchet wheel is oval shaped such that it pushes against said flywheel with different forces as the oval rotates.

13. The device of claim 10 wherein said ratchet wheel is engageably biased against said flywheel.

14. The device of claim 13 further comprising a solenoid mounted to engage said ratchet wheel with said flywheel.

15. The device of claim 14 further comprising a control circuit for causing said solenoid to disengage said ratchet wheel from said flywheel in response to determined conditions to allow free rotation of said rotatable wheel without a ratchet effect.

16. The device of claim 10 further comprising a spring for biasing said ratchet wheel against said flywheel.

17. A user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;a flywheel mounted in engagement with said rotatable wheel, wherein said flywheel is metal with a rubber tire mounted on its circumference;a ratchet wheel mounted for intermittent engagement with said flywheel;wherein said ratchet wheel is oval shaped such that it pushes against said flywheel with different forces as the oval rotates;a spring for biasing said ratchet wheel against said flywheel; anda solenoid mounted to engage said ratchet wheel with said flywheel.

18. A user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;an electro-permanent magnet mounted in said device; anda rotor made of a material which will magnetically interact with said electro-permanent magnet and coupled to said rotatable wheel and operative, in conjunction with said electro-permanent magnet, to provide a force to said rotatable wheel.

19. The device of claim 18 further comprising a controller coupled to said wheel sensor and said electro-permanent magnet, configured to pulse said electro-permanent magnet to modify its state to provide a ratchet force in response to the turning of said wheel.

20. A user input device for interfacing with a host computer, comprising: a rotatable wheel mounted in said input device, said wheel being rotatable by a finger of a user;a wheel sensor mounted in said input device and providing a wheel signal to said host computer indicating a rotary position of said wheel;a permanent magnet mounted in said device;a keeper mounted adjacent said permanent maget;an actuator coupled to said keeper so that said keeper can be moved over said permanent magnet to constrain the flux from said permanent magnet, and can be removed from said permanent magnet to allow said flux to escape; anda rotor made of a material which will magnetically interact with said permanent magnet and coupled to said rotatable wheel and operative, in conjunction with said magnets, to provide a force to said rotatable wheel.

21. The device of claim 20 further comprising a controller coupled to said wheel sensor and said actuator, configured to pulse said actuator to move said keeper to modify the flux from said permanent magnet to provide a ratchet force in response to the turning of said wheel.

22. A roller wheel for use in a user input device comprising a roller wheel body;at least a first coil rotationally coupled to the roller wheel body; anda set of magnets coupled to the roller wheel body and configured to rotate with the roller wheel body, and rotate relative to the coil;wherein current is configured to be driven through the coil to provide magnetic interaction between the coil and the magnet to provide a ratcheting force as the roller wheel body is rotated.

23. The roller wheel of claim 21, wherein if no current is driven through the coil than the roller wheel is configured to rotate in a smooth-roller mode.

24. The roller wheel of claim 21, The roller wheel of claim 21, further comprising a set of magnetic field sensors, wherein the magnets are configured to rotate relative to the magnetic field sensors and the magnetic field sensors are configured to detect the changing magnetic field from the rotating magnets for encoding rotation of the roller wheel body.

25. The roller wheel of claim 24, wherein the magnetic field sensors include Hall effect sensors.

26. The roller wheel of claim 21, further comprising a second coil, wherein the first mentioned coil and the second coil are configured to rotate the roller wheel body based on current driven alternately through the coils.