US3789700A — Positive drive roller planetary wave generator

Claim 1

Independent Claim 158 words

A wave generator for driving a harmonic drive flexspline provided with circumferential spline teeth, the wave generator comprising a sun gear coaxial with the flexspline, a pair of planetary roller pinions respectively diametrically meshing with the sun gear and the flexspline and radially deflecting the latter, the sum of the pitch diameters of the sun and pinion gears measured in a radial direction being different than the pitch diameter of the teeth of the flexspline in its relaxed circular form and substantially equal to the pitch diameter of the mating teeth of the flexspline, as measured between diametrically opposite points corresponding to planetary roller pinion contacts therewith to impart predetermined radial deflection thereto, and each of the planetary roller pinions having on axially opposite sides a plain planetary roller for bearing diametrically on a plain bearing surface of the sun gear and on an attenuator ring lining the interior of the flexspline adjacent to its internal gear teeth.

Claim 2

Dependent Claim 158 words

A wave generator for driving a harmonic drive flexspline provided with circumferential spline teeth, the wave generator comprising a sun gear coaxial with the flexspline, a pair of planetary roller pinions respectively diametrically meshing with the sun gear and the flexspline and radially deflecting the latter, the sum of the pitch diameters of the sun and pinion gears measured in a radial direction being different than the pitch diameter of the teeth of the flexspline in its relaxed circular form and substantially equal to the pitch diameter of the mating teeth of the flexspline, as measured between diametrically opposite points corresponding to planetary roller pinion contacts therewith to impart predetermined radial deflection thereto, and each of the planetary roller pinions having on axially opposite sides a plain planetary roller for bearing diametrically on a plain bearing surface of the sun gear and on an attenuator ring lining the interior of the flexspline adjacent to its internal gear teeth.

Claim 3

Dependent Claim 55 words

A wave generator as in claim 1 wherein a pair of roller skew control rings axially confine the wave generator elements in assembled relation to the flexspline, the control rings having, respectively, a circular peripheral portion of diameter substantially equal to the minor axis of the adjacent attenuator ring and disposed for potential engagement therewith.

Claim 4

Dependent Claim 166 words

In a harmonic drive actuator of the type having a rotary input shaft and a coaxial flexspline having at least first and second sets of teeth, the first of which sets meshes at spaced circumferential points with the circumferential spline teeth of a circular spline, a roller planetary wave generator driven by said shaft to elliptoidally shape the flexspline and circumferentially advance the points of meshing between the first set of flexspline teeth and the circular spline, the wave generator comprising a sun gear secured for rotation with the shaft and having means for coaxially supporting on an axial side thereof a sun roller, a pair of diametrically opposed roller planetary gears meshing with the sun gear and with the second set of flexspline teeth, a flexible ring engaging and deflectible with a surface of the flexspline opposite to its first set of teeth, and a pair of plain planetary rollers respectively bearing, at diametrically opposite localities on the flexible ring and on said sun roller.

Claim 5

Dependent Claim 166 words

In a harmonic drive actuator of the type having a rotary input shaft and a coaxial flexspline having at least first and second sets of teeth, the first of which sets meshes at spaced circumferential points with the circumferential spline teeth of a circular spline, a roller planetary wave generator driven by said shaft to elliptoidally shape the flexspline and circumferentially advance the points of meshing between the first set of flexspline teeth and the circular spline, the wave generator comprising a sun gear secured for rotation with the shaft and having means for coaxially supporting on an axial side thereof a sun roller, a pair of diametrically opposed roller planetary gears meshing with the sun gear and with the second set of flexspline teeth, a flexible ring engaging and deflectible with a surface of the flexspline opposite to its first set of teeth, and a pair of plain planetary rollers respectively bearing, at diametrically opposite localities on the flexible ring and on said sun roller.

Claim 6

Dependent Claim 49 words

An actuator as set forth in claim 3 wherein a sun roller is carried by the sun gear on axially opposite sides thereof, and the roller planetary gears each carry on axially opposite sides thereof a plain planetary roller respectively having bearing on one of the two sun rollers.

Claim 7

Dependent Claim 48 words

An actuator as set forth in claim 3 wherein at least one skew control ring is provided having a portion with diameter of substantially the inside diameter at the minor axis of the flexible ring, the control ring being disposed for peripheral potential engagement by the flexible ring.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1977-02-04	1977-08-06	1978-02-05	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1981-02-04	1981-08-06	1982-02-05	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1985-02-04	1985-08-06	1986-02-05	$7700.00	Window Closed / Lapsed

Positive drive roller planetary wave generator

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