Pure rolling cycloids with variable effective diameter rollers

Patent metadata

Field	Value
Publication number	US-10876608-B2
Application number	US-202016856848-A
Country	US
Kind code	B2
Filing date	Apr 23, 2020
Priority date	Jun 26, 2015
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

An apparatus includes a first ring having an open annular space and a variable-width groove disposed on an interior peripheral surface of the first ring; a second ring rotatable within the open annular space of the first ring, where the second ring has a respective variable-width groove disposed on an exterior peripheral surface of the second ring; and a plurality of rollers disposed between, and configured to roll on, the interior peripheral surface of the first ring and the exterior peripheral surface of the second ring and rotatable therebetween.

First claim

What is claimed is:

1. An apparatus comprising:
a first outer ring having an open annular space and a first-outer-ring variable-width groove disposed on an interior peripheral surface of the first outer ring;
a first inner ring rotatable within the open annular space of the first outer ring, wherein the first inner ring has a first-inner-ring variable-width groove disposed on an exterior peripheral surface of the first inner ring;
a first plurality of rollers disposed between, and configured to roll on, the interior peripheral surface of the first outer ring and the exterior peripheral surface of the first inner ring and rotatable therebetween while engaging the first-outer-ring variable-width groove and the first-inner-ring variable width groove;
a second outer ring having an open annular space and a second-outer-ring variable-width groove disposed on an interior peripheral surface of the second outer ring;
a second inner ring rotatable within the open annular space of the second outer ring, wherein the second inner ring has a second-inner-ring variable-width groove disposed on an exterior peripheral surface of the second inner ring; and
a second plurality of rollers disposed between, and configured to roll on, the interior peripheral surface of the second outer ring and the exterior peripheral surface of the second inner ring and rotatable therebetween while engaging the second-outer-ring variable-width groove and the second-inner-ring variable width groove,
wherein the first outer ring is coupled to the second outer ring and the first inner ring is coupled to the second inner ring.

2. The apparatus of claim 1 , wherein the interior peripheral surface of the first outer ring is aligned with the interior peripheral surface of the second outer ring.

3. The apparatus of claim 2 , wherein the exterior peripheral surface of the first inner ring is aligned with the exterior peripheral surface of the second inner ring.

4. The apparatus of claim 1 , wherein the rollers of the second plurality of rollers are aligned with the rollers of the first plurality of rollers.

5. The apparatus of claim 1 , wherein the rollers of the second plurality of rollers are not aligned with the rollers of the first plurality of rollers.

6. The apparatus of claim 1 , wherein:
the first-outer-ring variable-width groove defines a plurality of regions, such that each region of the plurality of regions starts with a first width at a first end of the region, increases to a second width larger than the first width at a center of the region, and narrows back to the first width at a second end of the region, and
the first-inner-ring variable-width groove defines a respective plurality of regions, such that each respective region of the respective plurality of regions starts with the first width at a respective first end of the respective region, increases to the second width at a respective center of the respective region, and narrows back to the first width at a respective second end of the respective region.

7. The apparatus of claim 6 , wherein:
a total number of regions defined by the first-inner-ring variable-width groove is smaller than a total number of regions defined by the first-outer-ring variable-width groove, and
a total number of the first plurality of rollers is less than the total number of regions defined by the first-outer-ring variable-width groove and greater than the total number of regions defined by the first-inner-ring variable-width groove.

8. The apparatus of claim 1 , wherein:
the second-outer-ring variable-width groove defines a plurality of regions, such that each region of the plurality of regions starts with a first width at a first end of the region, increases to a second width larger than the first width at a center of the region, and narrows back to the first width at a second end of the region, and
the second-inner-ring variable-width groove defines a respective plurality of regions, such that each respective region of the respective plurality of regions starts with the first width at a respective first end of the respective region, increases to the second width at a respective center of the respective region, and narrows back to the first width at a respective second end of the respective region.

9. The apparatus of claim 8 , wherein:
a total number of regions defined by the second-inner-ring variable-width groove is smaller than a total number of regions defined by the second-outer-ring variable-width groove, and
a total number of the second plurality of rollers is less than the total number of regions defined by the second-outer-ring variable-width groove and greater than the total number of regions defined by the second-inner-ring variable-width groove.

10. The apparatus of claim 1 , further comprising:
an input shaft coupled to the first inner ring and the second inner ring.

11. The apparatus of claim 10 , wherein the first and second inner rings are eccentrically coupled to the input shaft such that the first and second inner rings are offset from the input shaft in the same direction.

12. The apparatus of claim 10 , wherein the first and second inner rings are eccentrically coupled to the input shaft such that the first and second inner rings are offset from the input shaft in different directions.

13. The apparatus of claim 10 , further comprising:
a first drive member eccentrically mounted to the input shaft and coupled to the first inner ring; and
a second drive member eccentrically mounted to the input shaft and coupled to the second inner ring.

14. The apparatus of claim 1 , further comprising:
an output coupled to at least one of the first inner ring or the second inner ring.

15. The apparatus of claim 1 , further comprising:
a first output coupled to the first inner ring; and
a second output coupled to the second inner ring.

Assignees

• Stanford Res Inst Int

Inventors

• Kernbaum Alexander Steele
• Salisbury Curt

Classifications

• F16H1/28 Primary

  with gears having orbital motion · CPC title

• F16C19/26 Primary

  with a single row of rollers · CPC title

• F16C33/32

  Balls · CPC title

• F16H13/06

  with members having orbital motion · CPC title

• F16C33/46

  Cages for rollers or needles · CPC title