Pure rolling cycloids with variable effective diameter rollers

Patent metadata

Field	Value
Publication number	US-10670119-B2
Application number	US-201615738706-A
Country	US
Kind code	B2
Filing date	Jun 24, 2016
Priority date	Jun 26, 2015
Publication date	Jun 2, 2020
Grant date	Jun 2, 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 ring having an open annular space and a series of variable-width cutouts disposed on an interior peripheral surface of the first ring;
a second ring rotatable within the open annular space of the first ring, wherein the second ring has a respective series of variable-width cutouts 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, wherein:
the first ring has a total number of variable-width cutouts and the second ring has a total number of variable-width cutouts, with the total number of variable-width cutouts of the second ring being smaller than the total number of variable-width cutouts of the first ring, and a total number of the plurality of rollers being less than the total number of variable-width cutouts of the first ring and greater than the total number of variable-width cutouts of the second ring.

2. The apparatus of claim 1 , wherein as a given roller of the plurality of rollers traverses a variable-width cutout of either the variable-width cutouts of the first ring or the variable-width cutouts of the second ring, a radial distance between a center of the first ring and the given roller varies.

3. The apparatus of claim 1 , wherein at least one cutout of the variable-width cutouts starts with a first width at a first end of the cutout, increases to a second width larger than the first width at a center of the cutout, and narrows back to the first width at a second end of the cutout.

4. The apparatus of claim 1 , further comprising:
a roller cage disposed between the first ring and the second ring and configured to couple the plurality of rollers to each other, wherein the roller cage is rotatable in the open annular space of the first ring as the plurality of rollers roll between the interior peripheral surface of the first ring and the exterior peripheral surface of the second ring.

5. The apparatus of claim 4 , wherein the roller cage couples the plurality of rollers such that the rollers are equidistant from each other.

6. The apparatus of claim 1 , wherein the plurality of rollers are spherical.

7. The apparatus of claim 1 , wherein the plurality of rollers each have a rhombic cross section in a plane parallel to an axis of rotation of the second ring and a circular cross section in a plane perpendicular to the axis of rotation of the second ring.

8. The apparatus of claim 1 , wherein the interior peripheral surface of the first ring has a variable-width groove disposed therein, wherein a width of the variable-width groove varies between a first width and a second width larger than the first width, wherein the variable-width cutouts comprise regions of the variable-width groove that increase from the first width to the second width and back to the first width, and wherein the variable-width cutouts are separated by portions of the variable-width groove having the first width.

9. The apparatus of claim 1 , wherein the first ring is fixed.

10. An apparatus comprising:
a first ring having an open annular space and a plurality of depressions spatially arranged in series along an interior peripheral surface of the first ring, wherein a groove is disposed in the interior peripheral surface including the plurality of depressions;
a second ring rotatable within the open annular space of the first ring, wherein the second ring has a respective plurality of depressions spatially arranged in series along an exterior peripheral surface of the second ring, and wherein a respective groove is disposed in the exterior peripheral surface including the respective plurality of depressions; and
a plurality of rollers configured to engage, and roll within, the groove disposed in the interior peripheral surface and the respective groove disposed in the exterior peripheral surface as the second ring rotates within the open annular space of the first ring.

11. The apparatus of claim 10 , wherein:
the first ring has a total number of depressions and the second ring has a total number of depressions, with the total number of depressions of the second ring being smaller than the total number of depressions of the first ring, and a total number of the plurality of rollers being less than the total number of depressions of the first ring and greater than the total number of depressions of the second ring.

12. The apparatus of claim 10 , further comprising:
a roller cage disposed between the first ring and the second ring and configured to couple the plurality of rollers to each other, wherein the roller cage is rotatable in the open annular space as the plurality of rollers roll between the interior peripheral surface of the first ring and the exterior peripheral surface of the second ring.

13. The apparatus of claim 10 , wherein either the first ring or the second ring is fixed.

14. The apparatus of claim 10 , wherein as a given roller of the plurality of rollers traverses the groove and the plurality of depressions of the first ring and the respective groove and the respective plurality of depressions of the second ring, a radial distance between a center of the first ring and the given roller varies.

15. An apparatus comprising:
a first ring having an open annular space and a variable-width groove disposed on an interior peripheral surface of the first ring, wherein the variable-width groove of the first ring defines a plurality of regions, such that at least one 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;
a second ring rotatable within the open annular space of the first ring, wherein the second ring has a respective variable-width groove disposed on an exterior peripheral surface of the second ring, wherein the respective variable-width groove of the second ring defines a respective plurality of regions, such that at least one 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; 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 while engaging the variable-width groove of the first ring and the respective variable width groove of the second ring, wherein a total number of regions defined by the variable-width groove of the second ring is smaller than a total number of regions defined by the respective variable-width groove of the first ring and a total number of the plurality of rollers is less than the total number of regions defined by the variable-width groove of the first ring and greater than the total number of regions defined by the respective variable-width groove of the second ring.

16. The apparatus of claim 15 , wherein as a given roller of the plurality of rollers traverses the variable-width groove of the first ring and the respective variable-width groove of the second ring, a radial distance between a center of the second ring and the given roller varies.

17. The apparatus of claim 15 , wherein the variable-wi

Assignees

• Stanford Res Inst Int

Inventors

• Kernbaum Alexander Steele
• Salisbury Curt

Classifications

• F16H13/08 Primary

  with balls or with rollers acting in a similar manner · CPC title

• F16H1/28 Primary

  with gears having orbital motion · CPC title

• F16H13/06

  with members having orbital motion · CPC title

• F16C33/32

  Balls · CPC title

• F16C33/34

  Rollers; Needles · CPC title