Back to results
US 9,309,806 B2Granted
Rotational drive apparatus
AssigneeDenso Corporation
InventorsTomonobu Kuroda, Tetsuji Yamanaka, Naoaki Kouno
Life of this patent
Estimating the term…
Abstract
A first internal gear of a speed reducer includes an internally-toothed portion and a bearing portion and is formed as a one-piece member that is formed separately from a first housing. The internally-toothed portion forms internal teeth, which are meshed with external teeth of a first planetary gear. The bearing portion includes an eleventh cylindrical surface, which supports a motor shaft. The internal teeth of the first internal gear are arranged coaxial with the eleventh cylindrical surface. The internal teeth of the first internal gear and the bearing portion are formed as portions of the one-piece member.
Claims20
A rotational drive apparatus comprising:
- a first housing:
- an electric motor that is received in the first housing;
- a second housing that is fitted to the first housing and is fixed to the first housing;
- an output shaft that is coaxial with a motor shaft of the electric motor and is rotatably supported by the second housing;
- an eccentric shaft that is eccentric to the motor shaft and is rotatable integrally with the motor shaft;
- a first internal gear that is coaxial with the motor shaft and is formed separately from the first housing and the second housing, wherein the first internal gear is entirely received in an inside of the first housing and is non-rotatably fitted to an inner wall surface of the first housing;
- a first planetary gear that is meshed with the first internal gear from a radially inner side of the first internal gear, wherein the first planetary gear is rotatably supported by the eccentric shaft to enable rotation of the first planetary gear around the eccentric shaft, and at a time of rotating the motor shaft, the first planetary gear revolves around the motor shaft while changing a meshed location of the first planetary gear that is meshed with the first internal gear, and the first planetary gear is rotated about the eccentric shaft at a reduced speed that is reduced from a rotational speed of the motor shaft;
- and
- a rotation transmitting device that transmits rotation of the first planetary gear, which is rotated about the eccentric shaft, to the output shaft, wherein:
- the first internal gear is a one-piece member and is formed separately from the first housing, wherein the first internal gear includes:
- an internally-toothed portion that is tubular and is fitted to the first housing, wherein the internally-toothed portion has a plurality of internal teeth that are meshed with a plurality of external teeth of the first planetary gear;
- a bearing portion, which is configured into a tubular form and supports the motor shaft;
- and
- a flange portion, which connects between the internally-toothed portion and the bearing portion.
11 more elements
A rotational drive apparatus comprising:
- a first housing:
- an electric motor that is received in the first housing;
- a second housing that is fitted to the first housing and is fixed to the first housing;
- an output shaft that is coaxial with a motor shaft of the electric motor and is rotatably supported by the second housing;
- an eccentric shaft that is eccentric to the motor shaft and is rotatable integrally with the motor shaft;
- a first internal gear that is coaxial with the motor shaft and is non-rotatably fitted to the first housing;
- a first planetary gear that is meshed with the first internal gear from a radially inner side of the first internal gear, wherein the first planetary gear is rotatably supported by the eccentric shaft to enable rotation of the first planetary gear around the eccentric shaft, and at a time of rotating the motor shaft, the first planetary gear revolves around the motor shaft while changing a meshed location of the first planetary gear that is meshed with the first internal gear, and the first planetary gear is rotated about the eccentric shaft at a reduced speed that is reduced from a rotational speed of the motor shaft;
- and
- a rotation transmitting device that transmits rotation of the first planetary gear, which is rotated about the eccentric shaft, to the output shaft, wherein:
- the first internal gear is a one-piece member and is formed separately from the first housing, wherein the first internal gear includes:
- an internally-toothed portion that is tubular and is fitted to the first housing, wherein the internally-toothed portion has a plurality of internal teeth that are meshed with a plurality of external teeth of the first planetary gear;
- a bearing portion, which is configured into a tubular form and supports the motor shaft;
- and
- a flange portion, which connects between the internally-toothed portion and the bearing portion,
- the internally-toothed portion is axially displaced from the bearing portion;
- the flange portion is placed on a radially outer side of the bearing portion and includes:
- a tubular section that is connected to the internally-toothed portion;
- and
- a bottom section that connects between an end part of the tubular section, which is opposite from the internally-toothed portion of the tubular section, and the bearing portion;
- the tubular section of the flange portion includes a primary through-hole that radially extends through the tubular section;
- and
- the bottom section of the flange portion includes a secondary through-hole that axially extends through the bottom section and receives a motor terminal of the electric motor.
19 more elements
Dependencies are inferred from the claim text.