Hybrid gear drive
AssigneeThe Board of Trustees of the University of Illinois
InventorsFaydor L. Litvin, Aleksandar Egelja, Inhwan Seol
Life of this patent
Estimating the term…
Abstract
A hybrid gear drive suitable for the transformation of motion and power between an involute worm and a face gear wherein the axis of the face gear and the worm may be crossed or intersected. The gear drive includes a multi-thread involute worm in meshing engagement with a face gear having helical teeth. The multi-thread involute worm threads each have a driving surface and a coasting surface formed in the profiles of the involutes of a pair of base circles having different radii. The gear drive allows practical gear ratios up to about ten for high speed, high load applications such as helicopter or automobile gearboxes.
Claims31
An apparatus, comprising:
- a face gear having a face gear axis, said face gear having a plurality of teeth;
- and
- a multi-thread involute worm in meshing engagement with a portion of said plurality of teeth, each of said multi-threads has a driving surface formed at a first base circle with a first radius and a coast surface formed at a second base circle with a second radius, and wherein said first radius and second radius are unequal and said worm has a worm axis that is not parallel with said face gear axis.
A combination, comprising:
- a gas turbine engine;
- a gear box coupled to said engine;
- and
- a gear set positioned within said gear box, said gear set comprising:
- a face gear having a face gear axis, said face gear having a plurality of face gear teeth;
- and a multi-thread involute worm in meshing engagement with said plurality of face gear teeth, each of said multi-threads has a driving surface formed at a first base circle with a first radius and a coasting surface formed at a second base circle with a second radius, and wherein said first radius and second radius are unequal and said worm has a worm axis that is not parallel with said face gear axis.
A gear drive, comprising:
- a face gear having a face gear axis and a plurality of teeth;
- and
- a multi-thread involute worm in meshing engagement with a portion of said plurality of teeth, each of said multi-threads has a driving surface with a first pressure angle and a coast surface with a second pressure angle, and wherein said first and second pressure angles are unequal and said worm has a worm axis that is intersected with said face gear axis.
A gear drive, comprising:
- a face gear having a face gear axis and a plurality of teeth;
- and
- a multi-thread involute worm in meshing engagement with a portion of said plurality of teeth, each of said multi-threads has a driving surface with a first pressure angle and a coast surface with a second pressure angle, and wherein said second pressure angle is greater than said first pressure angle and said worm has a worm axis that is not parallel with said face gear axis.
A gear drive, comprising:
- a face gear having a face gear axis and a plurality of teeth;
- and
- a multi-thread involute worm in meshing engagement with a portion of said plurality of teeth, said worm has a cylindrical pitch surface, and said multi-threads has a driving surface with a first pressure angle and a coast surface with a second pressure angle, and wherein said first and second pressure angles are unequal and said worm has a worm axis that is not parallel with said face gear axis.
Dependencies are inferred from the claim text.