Bearing device, speed reduction mechanism including the bearing device, and motor torque transmission device

• US 8,827,854 B2
• Filed: 09/05/2012
• Issued: 09/09/2014
• Est. Priority Date: 09/08/2011
• Status: Active Grant

• Current Assignee: Jtekt Corporation (Toyota Motor Corporation)
• Original Assignee: Jtekt Corporation (Toyota Motor Corporation)
• Inventors: Nomura, Keita, Takuno, Hiroshi, Yamamoto, Takeshi
• Primary Examiner(s): LEWIS, TISHA D
• Application Number:
  US13/603,871
• Publication Number:
  US 20130065722A1
• Time in Patent Office: 734 Days
• Field of Search: 475169-181, 384437-475, 184/6
• US Class Current: 475/170
• CPC Class Codes: B60K 1/00 Arrangement or mounting of electrical propulsion units B60K7/00 takes precedence; arrangement or mounting of plural diverse prime-movers for mutual or common propulsion B60K6/00; electric transmission arrangements B60K17/12; electric equipment or propulsion of electrically-propelled vehicles per se B60L; current-collectors for power supply lines of electrically-propelled vehicles B60L5/00
• CPC Class Codes: B60K 17/356 having fluid or electric motor, for driving one or more wheels disposition of motor in, or adjacent to, traction wheel B60K7/00
• CPC Class Codes: B60K 2001/001 one motor mounted on a propulsion axle for rotating right and left wheels of this axle
• CPC Class Codes: B60L 2240/48 related to transmissions
• CPC Class Codes: B60L 2260/28 Four wheel or all wheel drive
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: F16C 19/06 with a single row or balls
• CPC Class Codes: F16C 19/26 with a single row of rollers
• CPC Class Codes: F16C 2361/61 Toothed gear systems, e.g. support of pinion shafts in general F16H57/02
• CPC Class Codes: F16C 2380/26 Dynamo-electric machines or combinations therewith, e.g. electro-motors and generators in general H02K
• CPC Class Codes: F16C 2380/27 Motor coupled with a gear, e.g. worm gears
• CPC Class Codes: F16C 33/3843 formed as one-piece cages, i.e. monoblock cages
• CPC Class Codes: F16C 33/414 formed as one-piece cages, i.e. monoblock comb cages
• CPC Class Codes: F16C 33/4623 formed as one-piece cages, i.e. monoblock cages
• CPC Class Codes: F16C 33/6681 Details of distribution or circulation inside the bearing, e.g. grooves on the cage or passages in the rolling elements
• CPC Class Codes: F16H 2001/325 comprising a carrier with pins guiding at least one orbital gear with circular holes
• CPC Class Codes: F16H 57/0428 Grooves with pumping effect for supplying lubricants
• CPC Class Codes: F16H 57/0471 Bearing
• CPC Class Codes: F16H 57/0486 with fixed gear ratio differentials F16H57/0483
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A cage of each of ball bearings arranged on respective outer peripheries of eccentric portions of a motor shaft has an annular base portion interposed between an inner ring and an outer ring and a plurality of partition wall portions for forming pockets together with the base portion. In a first ball bearing, part of the base portion protrudes axially outward from the inner raceway and forms an oil receiving portion that receives lubricating oil from the second rolling bearing side, at a portion around the rotation axis and axially outward of the first rolling bearing.

Claims

1. A bearing device, comprising:

a rotary shaft that has at least two eccentric portions that are arranged at equal intervals around a rotation axis of the rotary shaft, and that have respective central axes that are spaced apart at equal interval from the rotation axis in a radial direction of the rotary shaft; and

at least two rolling bearings that include a first rolling bearing and a second rolling bearing, that are respectively arranged on outer peripheries of the at least two eccentric portions of the rotary shaft, and each of which includes a plurality of rolling elements that roll between an inner raceway and an outer raceway and a cage by which the rolling elements are rollably retained at equal intervals around the corresponding central axis, wherein

the cage of each of the at least two rolling bearings has an annular base portion that is interposed between the inner raceway and the outer raceway and a plurality of partition wall portions for forming pockets together with the base portion, and

in the first rolling bearing, part of the base portion protrudes axially outward from the inner raceway and forms an oil receiving portion that receives lubricating oil from the second rolling bearing side, at a portion around the rotation axis and axially outward of the first rolling bearing.

2. The bearing device according to claim 1, wherein:

the rotary shaft is formed of a hollow shaft member that has an oil supply passage that is open at an inner periphery and an outer periphery of the hollow shaft member; and

each of the at least two rolling bearings is formed such that, in the second rolling bearing, part of the base portion protrudes axially outward from the inner raceway and forms an oil receiving portion that receives lubricating oil from the oil supply passage.

3. A speed reduction mechanism, comprising:

a speed reduction unit that includes input members and outputs member, and that reduces a speed of rotation input into the input members and outputs the rotation with a reduced speed from the output members; and

a bearing unit by which the input members of the speed reduction unit are rotatably supported around respective central axes of the input members, wherein

the bearing unit is the bearing device according to claim 1, and

the input members of the speed reduction unit include a first input member that is supported by the first rolling bearing, and a second input member that is supported by the second rolling bearing.

4. A speed reduction mechanism, comprising:

a speed reduction unit that includes input members and outputs member, and that reduces a speed of rotation input into the input members and outputs the rotation with a reduced speed from the output members; and

a bearing unit by which the input members of the speed reduction unit are rotatably supported around respective central axes of the input members, wherein

the bearing unit is the bearing device according to claim 2, and

the input members of the speed reduction unit include a first input member that is supported by the first rolling bearing, and a second input member that is supported by the second rolling bearing.

5. The speed reduction mechanism according to claim 3, wherein:

in the bearing unit, the rotary shaft has a first oil flow passage that is open at a position between the inner raceway and the outer raceway of the second rolling bearing; and

in the speed reduction unit, the second input member has a second oil flow passage that communicates with the first oil flow passage and that is open at a position between the inner raceway and the outer raceway in the first rolling bearing.

6. The speed reduction mechanism according to claim 4, wherein:

in the bearing unit, the rotary shaft has a first oil flow passage that is open at a position between the inner raceway and the outer raceway of the second rolling bearing; and

in the speed reduction unit, the second input member has a second oil flow passage that communicates with the first oil flow passage and that is open at a position between the inner raceway and the outer raceway in the first rolling bearing.

7. A motor torque transmission device, comprising:

an electric motor that generates motor torque; and

a reduction-transmission mechanism that reduces a speed of rotation of the electric motor and transmits driving force to a driving force transmitted target, wherein

the reduction-transmission mechanism is the speed reduction mechanism according to claim 3.

8. A motor torque transmission device, comprising:

an electric motor that generates motor torque; and

a reduction-transmission mechanism that reduces a speed of rotation of the electric motor and transmits driving force to a driving force transmitted target, wherein

the reduction-transmission mechanism is the speed reduction mechanism according to claim 4.

9. A motor torque transmission device, comprising:

an electric motor that generates motor torque; and

a reduction-transmission mechanism that reduces a speed of rotation of the electric motor and transmits driving force to a driving force transmitted target, wherein

the reduction-transmission mechanism is the speed reduction mechanism according to claim 5.

10. A motor torque transmission device, comprising:

an electric motor that generates motor torque; and

a reduction-transmission mechanism that reduces a speed of rotation of the electric motor and transmits driving force to a driving force transmitted target, wherein

the reduction-transmission mechanism is the speed reduction mechanism according to claim 6.

11. The motor torque transmission device according to claim 7, wherein

the reduction-transmission mechanism transmits the driving force to a differential mechanism that serves as the driving force transmitted target.

12. The motor torque transmission device according to claim 8, wherein

the reduction-transmission mechanism transmits the driving force to a differential mechanism that serves as the driving force transmitted target.

13. The motor torque transmission device according to claim 9, wherein

the reduction-transmission mechanism transmits the driving force to a differential mechanism that serves as the driving force transmitted target.

14. The motor torque transmission device according to claim 10, wherein

the reduction-transmission mechanism transmits the driving force to a differential mechanism that serves as the driving force transmitted target.