Claims
- 1. A dolly wheel assembly, comprising:
a dolly wheel; a dolly wheel spindle fixedly secured to said dolly wheel such that said dolly wheel and said dolly wheel spindle rotate about an axis as a single unit; a dampening device in communication with said dolly wheel spindle to apply a resisting force to said dolly wheel spindle to resist free rotation of said dolly wheel, and a controller in communication with said dampening device such that said dampening device can apply said resisting force or remove said resisting force upon demand to satisfy a variety of different conditions encountered by a vehicle employing the dolly wheel assembly.
- 2. The assembly of claim 1, wherein said dampening device includes a electroviscous fluid located in a chamber that communicates with at least a portion of said dolly wheel spindle, such that upon application of a varying current, the viscosity of said electro-viscous fluid varies.
- 3. The assembly of claim 2, wherein said electroviscous fluid is magnetorheological fluid technology.
- 4. The assembly of claim 2, wherein said electroviscous fluid has a low viscosity when excited by current to allow said dolly wheel to have a high degree of maneuverability.
- 5. The assembly of claim 1, wherein said dampening device includes an electric motor having variable resistance of rotation in communication with said controller.
- 6. The assembly of claim 1, wherein said dampening device includes a hydraulic pump/motor system with a variable orifice for providing the ability to regulate variable resistance and braking of rotation in communication with said controller for desired operation.
- 7. The assembly of claim 1, wherein said dampening device includes a hydraulic pump/motor system utilizing an electroviscous fluid for providing the ability to regulate variable resistance and braking of rotation in communication with said controller for desired operation.
- 8. The assembly of claim 1, wherein said dampening device includes a mechanical détente system.
- 9. The assembly of claim 7, wherein said electroviscous fluid is magnetorheological fluid technology.
- 10. The assembly of claim 7, wherein said electroviscous fluid has a low viscosity when unexcited by current to allow said dolly wheel to have a high degree of maneuverability.
- 11. The assembly of claim 7, wherein said electroviscous fluid when excited by current can have a higher viscosity to apply a resisting force.
- 12. The assembly of claim 11, wherein said electroviscous fluid, when excited by current can be caused to have a higher viscosity to apply a resisting force.
- 13. The assembly of claim 12, wherein said electroviscous fluid can be caused to have a viscosity up to and including a semi-solid state to apply a braking force.
- 14. The assembly of claim 2, wherein application of said current is controlled by said controller.
- 15. The assembly of claim 1, wherein the dolly wheel assembly is incorporated into a mobility vehicle.
- 16. The assembly of claim 1, wherein said variety of different conditions include one or more of the following:
parking the vehicle on a hillside, maneuvering the vehicle on a hillside, maneuvering the vehicle in tight locations, or operating the vehicle in conditions of varying traction resulting in lessened control.
- 17. A dolly wheel assembly for a vehicle comprising:
a dolly wheel rotatably secured to the vehicle and having an axis of rotation; a dolly wheel spindle fixedly secured to said dolly wheel; a dampener device in communication with said dolly wheel spindle to apply a restricting force thereto; and a controller in communication with said dampener device to regulate application of said restricting force and the magnitude of said restricting force to be applied to said dolly wheel spindle depending upon dolly wheel requirements.
- 18. The dolly wheel assembly of claim 17, wherein said controller can apply said restricting force on demand.
- 19. The dolly wheel assembly of claim 17, wherein said restricting force can be a braking force to lock said dolly wheel spindle and prevent any movement of said dolly wheel with respect to said dolly wheel axis of rotation.
- 20. The dolly wheel assembly of claim 17, wherein the magnitude of said restricting force limits movement of said dolly wheel spindle, but allows said dolly wheel to be turned small amounts for purposes of corrective steering at higher vehicle speeds.
- 21. The dolly wheel assembly of claim 17, wherein said dampener device is an electroviscous dampener including electroviscous fluid which is in communication with said controller, said electroviscous fluid having a normal low viscosity to allow said dolly wheel to freely rotate about said dolly wheel axis.
- 22. The dolly wheel assembly of claim 21, wherein said electroviscous fluid is magnetorheological fluid technology.
- 23. The dolly wheel assembly of claim 21, wherein said dampener device is in communication with a current source and upon application of said current, said electroviscous fluid increases in viscosity up to and including a semi-solid state.
- 24. The dolly wheel assembly of claim 22, wherein when said electroviscous fluid has a viscosity of a semi-solid state resulting in said restricting force being a braking force such that rotation of said dolly wheel is prevented.
- 25. The dolly wheel assembly of claim 23, wherein said electroviscous fluid has a viscosity between said normal low viscosity and said semi-solid state, resulting in said restricting force being applied to said dolly wheel spindle to limit movement of said dolly wheel except for corrective steering.
- 26. The dolly wheel assembly of claim 25, wherein said controller is in communication with sensors and in concert with said electroviscous fluid can provide low viscosity for dolly wheel response to corrective steering and higher dampening viscosity after corrective steering action.
- 27. The dolly wheel assembly of claim 21, wherein said electroviscous fluid is located in a dolly wheel spindle housing.
- 28. The dolly wheel assembly of claim 21, wherein said electroviscous fluid is located in a separate dampener housing which is separate from, but in communication with, said dolly wheel spindle.
- 29. The dolly wheel assembly of claim 21, wherein said electroviscous dampener has a dampener housing having a plurality of surface contours formed on an inner peripheral surface thereof to communicate with said electroviscous fluid.
- 30. The dolly wheel assembly of claim 29, wherein said plurality of surface contours are radial ribs.
- 31. The dolly wheel assembly of claim 24, wherein said dolly wheel spindle has a plurality of surface contours formed on a peripheral surface thereof to communicate with said electroviscous fluid.
- 32. The dolly wheel assembly of claim 31, wherein said plurality of surface contours are radial ribs.
- 33. The dolly wheel assembly of claim 17, wherein said dampener device includes an electric motor having variable resistance of rotation in communication with said controller.
- 34. The dolly wheel assembly of claim 17, wherein said dampener device includes a hydraulic pump/motor system for providing the ability to regulate resistance and braking of rotation in communication with said controller for desired operation.
- 35. The dolly wheel assembly of claim 17, wherein said dampener device includes a mechanical détente system.
- 36. A method of restricting movement of a dolly wheel assembly, comprising:
securing a dolly wheel spindle to a dolly wheel such that said dolly wheel and said dolly wheel spindle rotate about an axis as a single unit; applying a restricting force to said dolly wheel spindle on demand to limit rotation of said dolly wheel about said axis to accommodate a variety of different conditions encountered by a vehicle employing the dolly wheel assembly; and removing said restricting force from said dolly wheel spindle on demand to allow said dolly wheel to rotate freely about said axis.
- 37. The method of claim 36, wherein said restrictive force can be a variable force that allows some rotation of said dolly wheel spindle about said axis.
- 38. The method of claim 36, wherein said restrictive force is a complete braking force.
- 39. The method of claim 36, wherein said restrictive force is applied by an electroviscous dampening device having an electroviscous fluid, and being in communication with said dolly wheel spindle, the viscosity of said electroviscous fluid increases upon application of a current.
- 40. The method of claim 36, wherein said restrictive force is applied by an electric motor having a variable resistance of rotation.
- 41. The method of claim 36, wherein said restrictive force is applied by a hydraulic pump/motor system with a variable orifice for providing the ability to regulate variable resistance and braking of rotation of said dolly wheel spindle.
- 42. The method of claim 36, wherein said restrictive force is applied by a hydraulic system using an electroviscous fluid providing the ability to regulate variable resistance and braking of rotation of said dolly wheel spindle.
- 43. The method of claim 36, wherein said restrictive force is a mechanical détente system.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims priority from U.S. Provisional Application Serial No. 60/293,873, entitled “Dolly Wheel Steering System Employing Speed Related Dampening,” filed May 25, 2001; U.S. Provisional Application Serial No. 60/293,848, entitled “Dual Mode Steering System For a Vehicle,” filed May 25, 2001; and U.S. Provisional Application Serial No. 60/317,008, entitled “Personal Mobility Vehicle,” filed Sep. 4, 2001.
Provisional Applications (3)
|
Number |
Date |
Country |
|
60293873 |
May 2001 |
US |
|
60293848 |
May 2001 |
US |
|
60317008 |
Sep 2001 |
US |