Cycloidal planetary gear speed reducer

Patent metadata

Field	Value
Publication number	US-9890832-B2
Application number	US-201515316332-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	Jul 7, 2014
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

The invention relates to a cycloidal planetary gear speed reducer having a central shaft, comprising at least one ring gear disposed so as to be rigidly mounted in a housing, a set of planet gears in mesh with the ring gear, a rotatably supported planet gear carrier, on which the planet gears are mounted, and a plurality of drive plates arranged axially one behind the other in order to drive the planet gears, wherein the drive plates are mounted eccentrically on the central shaft in order to execute a circular translation movement, wherein at any given time during execution of a circular translation movement, the drive plates are in engagement with at least two planet gears.

First claim

What is claimed is:

1. A cycloidal planetary gear speed reducer having a central shaft, comprising:
at least one ring gear disposed so as to be rigidly mounted in a housing,
a set of planet gears in mesh with the at least one ring gear,
a rotatably supported planet gear carrier, on which the planet gears are mounted, and
a plurality of drive plates arranged axially, one behind the other, in order to drive the planet gears, wherein the drive plates are mounted eccentrically on the central shaft in order to execute a circular translation movement, wherein at any given time during execution of a circular translation movement, the drive plates are in engagement with at least two planet gears, wherein in order to engage with three planet gears, the drive plates form in each case three concave circular arc-shaped tooth segments, which correspond with said three planet gears and which have internal gear teeth on the outer periphery, with said internal gear teeth having an opening angle that is greater than 180 degrees; or in order to engage with four planet gears, the drive plates form in each case four concave circular arc-shaped tooth segments, which correspond with these four planet gears and which have internal gear teeth on the outer periphery, with said internal gear teeth having an opening angle that is greater than 150 degrees.

2. The cycloidal planetary gear speed reducer of claim 1 , wherein the drive plates form, in each case, concave circular arc-shaped tooth segments having internal gear teeth on the outer periphery, wherein the internal gear teeth of the tooth segments, which follow one another in succession in the circumferential direction, exhibit a tooth offset, which is a function of the respective position of the tooth segments, by a predetermined angle with respect to each other.

3. The cycloidal planetary gear speed reducer of claim 2 , wherein the tooth offset of the internal gear teeth of the tooth segments, which follow one another in succession in the circumferential direction, is determined by means of an angle that is a function of the respective position of the tooth segments, the tooth count of the first ring gear, the tooth count of the internal gear teeth of the tooth segments, the number of planet gears and the gear ratio between the drive plates and the ring gear.

4. The cycloidal planetary gear speed reducer of claim 1 , wherein the drive plates form, in each case, concave circular arc-shaped tooth segments having internal gear teeth on the outer periphery, with said internal gear teeth having, in each case, a predetermined opening angle that is determined as a function of the number of planet gears, the length of the mesh line of action from its entry point up to its pitch point between the external gear teeth of the planet gears and the internal gear teeth of the tooth segments and as a function of the tip circle diameter and the pitch circle diameter of the internal gear teeth of the tooth segments.

5. The cycloidal planetary gear speed reducer of claim 1 , wherein the drive plates have in the circumferential direction recesses between the tooth segments on the outer periphery.

6. The cycloidal planetary gear speed reducer of claim 1 , wherein the drive plates have through-holes in a radially central region between the recesses on the outer periphery and a central receiving opening radially inwards.

7. The cycloidal planetary gear speed reducer of claim 1 , wherein the drive plates are made of sheet metal and are manufactured by punching.

Assignees

• Schaeffler Technologies Ag

Inventors

• Kurth Franz
• Schimpf Ralph

Classifications

• F16H1/32 Primary

  in which the central axis of the gearing lies inside the periphery of an orbital gear · CPC title

• F16H2035/003

  Gearings comprising pulleys or toothed members of non-circular shape, e.g. elliptical gears · CPC title

• F16H2049/008

  Linear wave gearings, i.e. harmonic type gearing imposing a strain wave to a straight flexible member engaging a second member with different pitch to generate linear motion thereof · CPC title

• F16H2001/327

  with the orbital gear having internal gear teeth · CPC title