Joint device and motor

Patent metadata

Field	Value
Publication number	US-9574616-B2
Application number	US-201514638687-A
Country	US
Kind code	B2
Filing date	Mar 4, 2015
Priority date	Mar 5, 2014
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A joint device includes a drive rotor fixed to a drive shaft, a driven rotor fixed to a driven shaft, and a ring-shaped buffer located between the drive rotor and the driven rotor. The drive rotor includes a drive engagement portion that projects toward the driven rotor in an axial direction. The driven rotor includes a driven engagement portion that projects toward the drive rotor in the axial direction. The buffer includes an outer surface, which includes a first engagement recess and a second engagement recess that are recessed toward a radially inner side. An outer diameter of a bottom surface of the second engagement recess is smaller than an inner diameter of the driven engagement portion or an outer diameter of a bottom surface of the first engagement recess is smaller than an inner diameter of the drive engagement portion.

First claim

The invention claimed is:

1. A joint device comprising:
a drive rotor fixed to a drive shaft;
a driven rotor fixed to a driven shaft; and
a ring-shaped buffer located between the drive rotor and the driven rotor, wherein;
the drive rotor includes a drive engagement portion that projects toward the driven rotor in an axial direction;
the driven rotor includes a driven engagement portion that projects toward the drive rotor in the axial direction;
the buffer includes an outer surface, which includes a first engagement recess and a second engagement recess that are recessed toward a radially inner side;
the drive engagement portion is inserted into the first engagement recess engageable in a rotation direction;
the driven engagement portion is inserted into the second engagement recess engageable in the rotation direction; and
an outer diameter of a bottom surface of the second engagement recess is smaller than an inner diameter of the driven engagement portion; and
the drive rotor and the driven rotor respectively include a drive contact portion and a driven contact portion, and the drive contact portion and the driven contact portion directly contact each other in the rotation direction when a load acting on the driven rotor is greater than or equal to a predetermined level.

2. The joint device according to claim 1 , wherein:
the outer diameter of the bottom surface of the second engagement recess is smaller than the inner diameter of the driven engagement portion; and
the outer diameter of the bottom surface of the first engagement recess is substantially equal to the inner diameter of the drive engagement portion.

3. The joint device according to claim 2 , wherein:
a circumferential width of the first engagement recess is substantially equal to a circumferential width of the drive engagement portion; and
a circumferential width of the second engagement recess is larger than a circumferential width of the driven engagement portion.

4. The joint device according to claim 1 , wherein:
the second engagement recess includes an arcuate surface extending around an axis;
the driven engagement portion includes an arcuate surface extending around the axis and opposed to the arcuate surface of the second engagement recess;
the first engagement recess includes an arcuate surface extending around an axis;
the drive engagement portion includes an arcuate surface extending around the axis and opposed to the arcuate surface of the first engagement recess; and
the arcuate surface of the second engagement recess has a smaller radius than the arcuate surface of the opposing driven engagement portion.

5. A motor comprising the joint device according to claim 1 .

6. A joint device comprising:
a drive rotor fixed to a drive shaft;
a driven rotor fixed to a driven shaft; and
a ring-shaped buffer located between the drive rotor and the driven rotor, wherein:
the drive rotor includes a drive engagement portion that projects toward the driven rotor in an axial direction;
the driven rotor includes a driven engagement portion that projects toward the drive rotor in the axial direction;
the buffer includes an outer surface, which includes a first engagement recess and a second engagement recess that are recessed toward a radially inner side;
the drive engagement portion is inserted into the first engagement recess engageable in a rotation direction;
the driven engagement portion is inserted into the second engagement recess engageable in the rotation direction;
an outer diameter of a bottom surface of the first engagement recess is smaller than an inner diameter of the drive engagement portion; and
the drive rotor and the driven rotor respectively include a drive contact portion and a driven contact portion, and the drive contact portion and the driven contact portion directly contact each other in the rotation direction when a load acting on the driven rotor is greater than or equal to a predetermined level.

7. The joint device according to claim 6 wherein:
the outer diameter of the bottom surface of the first engagement recess is smaller than the inner diameter of the drive engagement portion; and
the outer diameter of the bottom surface of the second engagement recess is substantially equal to the inner diameter of the driven engagement portion.

8. The joint device according to claim 7 , wherein:
a circumferential width of the second engagement recess is substantially equal to a circumferential width of the drive engagement portion; and
a circumferential width of the first engagement recess is larger than a circumferential width of the driven engagement portion.

9. The joint device according to claim 6 , wherein:
the second engagement recess includes an arcuate surface extending around an axis;
the driven engagement portion includes an arcuate surface extending around the axis and opposed to the arcuate surface of the second engagement recess;
the first engagement recess includes an arcuate surface extending around an axis;
the drive engagement portion includes an arcuate surface extending around the axis and opposed to the arcuate surface of the first engagement recess; and
the arcuate surface of the first engagement recess has a smaller radius than the arcuate surface of the opposing drive engagement portion.

10. A motor comprising the joint device according to claim 6 .

Assignees

• Asmo Co Ltd

Inventors

• Hakamata Kazuyuki

Classifications

• F16D3/02

  adapted to specific functions · CPC title

• H02K7/1166

  comprising worm and worm-wheel (structural association with bearings specially adapted for worm gear drives H02K7/081) · CPC title

• H02K7/003

  Couplings; Details of shafts (means for mounting rotors on shafts H02K1/28) · CPC title

• F16D3/68 Primary

  the elements being made of rubber or similar material · CPC title