Speed reducer, joint assembly and electric pendulum

Patent metadata

Field	Value
Publication number	US-12492740-B2
Application number	US-202418605698-A
Country	US
Kind code	B2
Filing date	Mar 14, 2024
Priority date	Mar 14, 2023
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

A joint assembly includes a speed reducer and a motor. The speed reducer includes a housing, an internal gear; an external gear at least partially arranged in an internal gear hole of the internal gear and meshing with the internal gear; an eccentric wheel rotatably and at least partially arranged in an external gear hole of the external gear; a limiting disc; and a drive member. A rotation axis of the eccentric wheel is coaxial with a central axis of the internal gear. The eccentric wheel drives the external gear to revolve around the rotation axis of the eccentric wheel. The drive member is driven to rotate by the motor. The drive member drives the eccentric wheel to rotate and hence drives the external gear to revolve around the rotation axis of the eccentric wheel in the internal gear hole of the internal gear, driving the internal gear to rotate.

First claim

What is claimed is:

1 . A speed reducer, comprising:
a housing; an internal gear rotatably and at least partially supported in the housing, the internal gear having a concentric internal gear hole having a peripheral surface with internal teeth arranged thereon and an internal gear through-hole; an external gear at least partially arranged in the concentric internal gear hole and having external teeth meshing with the internal teeth of the concentric internal gear hole to drive the internal gear to rotate, the external gear having an external gear through-hole; an eccentric wheel rotatably and at least partially arranged in the external gear through-hole, the eccentric wheel having an eccentric wheel hole extending through the eccentric wheel, wherein a rotation axis of the eccentric wheel is coaxial with a central axis of the internal gear, and the eccentric wheel is configured to drive the external gear to revolve around the rotation axis of the eccentric wheel; a limiting disc arranged in the housing, the limiting disc being engaged with the housing so that the limiting disc and the housing are limited to relative movement in a first direction, and the limiting disc being engaged with the external gear so that the limiting disc and the external gear are limited to relative movement in a second direction, wherein the first direction, the second direction, and an axial direction of the limiting disc are orthogonal to each other; a drive member connected to the eccentric wheel to drive the eccentric wheel to rotate, the drive member having a hole therethrough; and a positioning shaft connected to a wall of the housing and extending from the wall through the hole of the drive member, the eccentric wheel hole of the eccentric wheel, the external gear through-hole of the external gear, and the internal gear through-hole of the internal gear.

2 . The speed reducer according to claim 1 , wherein:
one of the limiting disc and the housing comprises a first limiting portion, and the other one of the limiting disc and the housing comprises a first limiting groove, the first limiting portion being fitted in the first limiting groove and being movable in the first direction; and one of the limiting disc and the external gear comprises a second limiting portion, and the other one of the limiting disc and the external gear comprises a second limiting groove, the second limiting portion being fitted in the second limiting groove and being movable in the second direction.

3 . The speed reducer according to claim 2 , wherein:
the first limiting portion is on the housing, the second limiting portion is on the external gear, and the first limiting groove and the second limiting groove are on the limiting disc; and two first limiting portions, two second limiting portions, two first limiting grooves, and two second limiting grooves are provided, wherein the two first limiting portions are opposite in the first direction and the two first limiting grooves are opposite in the first direction, and the two second limiting portions are opposite in the second direction and the two second limiting grooves are opposite in the second direction, wherein the limiting disc has roughly an oval shape.

4 . The speed reducer according to claim 2 , wherein the first limiting portion and the second limiting portion are prisms or cylindrical rods, and the first limiting groove and the second limiting groove are U-shaped grooves.

5 . The speed reducer according to claim 1 , wherein the drive member is a first gear, the first gear is rotatably supported in the housing and is connected to the eccentric wheel, and a rotation axis of the first gear is coaxial with the rotation axis of the eccentric wheel.

6 . The speed reducer according to claim 5 ,
wherein the housing has a first end and a second end, and the positioning shaft is connected to an end wall of the first end of the housing and extends towards the second end of the housing; wherein the eccentric wheel hole of the eccentric wheel, the hole of the drive member, and the internal gear through-hole of the internal gear are all coaxial with the internal gear.

7 . The speed reducer according to claim 5 , wherein the housing has a first end and a second end; an end wall of the first end of the housing comprises a central flange extending towards the second end of the housing; the first gear has a positioning groove coaxial with the rotation axis of the eccentric wheel; and the central flange is rotatably fitted in the positioning groove.

8 . The speed reducer according to claim 1 , wherein the housing has a first end and a second end; the second end of the housing is open and is covered by a cover plate; the cover plate has a cover plate hole; a part of the internal gear is located in the housing, and another part of the internal gear is rotatably supported in the cover plate hole.

9 . The speed reducer according to claim 8 , wherein an outer peripheral surface of the internal gear is a stepped surface to divide the internal gear into a large diameter portion and a small diameter portion; the large diameter portion is located in the housing; and the small diameter portion is rotatably fitted in the cover plate hole.

10 . A joint assembly, comprising:
a speed reducer, comprising
a housing,
an internal gear rotatably and at least partially supported in the housing, the internal gear having a concentric internal gear hole having a peripheral surface with internal teeth arranged thereon and an internal gear through-hole,
an external gear at least partially arranged in the concentric internal gear hole and having external teeth meshing with the internal teeth of the concentric internal gear hole to drive the internal gear to rotate, the external gear having an external gear through-hole,
an eccentric wheel rotatably and at least partially arranged in the external gear through-hole, the eccentric wheel having an eccentric wheel hole extending through the eccentric wheel, wherein a rotation axis of the eccentric wheel is coaxial with a central axis of the internal gear, and the eccentric wheel is configured to drive the external gear to revolve around the rotation axis of the eccentric wheel,
a limiting disc arranged in the housing, the limiting disc being engaged with the housing so that the limiting disc and the housing are limited to relative movement in a first direction, and the limiting disc being engaged with the external gear so that the limiting disc and the external gear are limited to relative movement in a second direction, wherein the first direction, the second direction, and an axial direction of the limiting disc are orthogonal to each other,
a drive member connected to the eccentric wheel to drive the eccentric wheel to rotate, the drive member having a hole therethrough, and
a positioning shaft connected to a wall of the housing and extending from the wall through the hole of the drive member, the eccentric wheel hole of the eccentric wheel, the external gear through-hole of the external gear, and the internal gear through-hole of the internal gear; and
a motor configured to drive the drive member to rotate.

11 . The joint assembly according to claim 10 , wherein:
the drive member of the speed reducer is a first gear connected to the eccentric wheel, and a rotation axis of the first gear is coaxial with the rotation axis of the eccentric wheel; and a motor shaft of the motor comprises a second gear, the second gear meshes with the first gear to drive the first gear to rotate, and the number of teeth of the first gear is greater than the number of teeth of the second gear.

12 . The joint assembly according t

Assignees

• T Max Hangzhou Tech Co Ltd

Inventors

• Yang Huizhong
• Yang Yilin

Classifications

• B25J9/102 Primary

  Gears specially adapted therefor, e.g. reduction gears (gearings in general F16H) · CPC title

• F16H1/32

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

• F16H2001/326

  comprising linear guiding means guiding at least one orbital gear · CPC title

• F16H1/16

  comprising worm and worm-wheel · CPC title

• F16H37/041

  for conveying rotary motion with constant gear ratio · CPC title