Differential device

Patent metadata

Field	Value
Publication number	US-9739364-B2
Application number	US-201514964754-A
Country	US
Kind code	B2
Filing date	Dec 10, 2015
Priority date	Dec 12, 2014
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

In a differential device, even when tooth portions of side gears are placed farther from output shafts due to increase in diameter of the side gears or even when a pinion rotates at high speed, seizure in meshing portions of the pinion and the side gears and a sliding portion of the pinion is prevented effectively. The side gears each include a shaft portion connected to corresponding one of the output shafts, and a flat intermediate wall portion integrally connecting the shaft portion and the tooth portion of the side gear separated outward from the shaft portion in a radial direction of an input member. A through oil passage is formed in the intermediate wall portion of at least one side gear, both ends of the through oil passage being respectively opened in inner and outer side surfaces of the intermediate wall portion.

First claim

What is claimed is:

1. A differential device which distributively transmits rotational force from an input member to a pair of output shafts via a pair of side gears, the input member supporting a pinion support portion that supports a pinion thereon, the pinion being rotatable together with the pinion support portion,
the side gears each having a tooth portion in mesh with the pinion in an outer peripheral portion of the side gear, wherein the side gears each include:
a shaft portion connected to a corresponding one of the pair of output shafts; and
an intermediate wall portion integrally connecting the shaft portion and the tooth portion, the intermediate wall portion separated outward from the shaft portion in a radial direction of the input member and being formed in a substantially flat shape, the differential device further comprising:
a cover portion including a side wall portion which covers an outer side surface of at least one of the side gears, and which is connected to the input member so as to rotate integrally with the input member; and
a washer installed between an inner side surface of the side wall portion and the outer side surface of the one of the side gears,

wherein a through oil passage is formed in the intermediate wall portion of at least one of the side gears, ends of the through oil passage being respectively opened in an inner side surface and an outer side surface of the intermediate wall portion,
and wherein an opening of the through oil passage is partially occluded by the washer.

2. The differential device according to claim 1 ,
wherein relative positions of the washer and the through oil passage are set such that at least an inner peripheral portion of the washer faces the opening of the through oil passage opened to the outer side surface of the intermediate wall portion.

3. The differential device according to claim 2 , wherein a washer retaining groove, fitting and retaining the washer therein, is formed in at least one of the inner side surface of the side wall portion and the outer side surface of the side gear.

4. The differential device according to claim 2 , wherein:
the side wall portion includes a weight-reduction portion exposing the outer side surface of the side gear, and
an oil guide groove is provided in a recess in the inner side surface of the side wall portion, the oil guide groove being capable of guiding flow of lubricant oil from a peripheral edge of the weight-reduction portion toward the washer and the through oil passage during rotation of the input member.

5. The differential device according to claim 3 , wherein
the side wall portion includes a weight-reduction portion exposing the outer side surface of the side gear, and
an oil guide groove is provided in a recess in the inner side surface of the side wall portion, the oil guide groove being capable of guiding flow of lubricant oil from a peripheral edge of the weight-reduction portion toward the washer and the through oil passage during rotation of the input member.

6. A differential device which distributively transmits rotational force from an input member to a pair of output shafts via a pair of output gears, the input member supporting a differential gear support portion that supports a differential gear thereon, the differential gear being rotatable together with the differential gear support portion, the output gears each having a tooth portion in mesh with the differential gear in an outer peripheral portion of each of the output gears, wherein
the pair of output gears each include:
a shaft portion connected to a corresponding one of the pair of output shafts; and
an intermediate wall portion integrally connecting the shaft portion and the tooth portion, the intermediate wall portion separated outward from the shaft portion in a radial direction of the input member and being formed in a substantially flat shape, the differential device further comprising:
a cover portion including a side wall portion which covers an outer side surface of at least one of the side gears, and which is connected to the input member so as to rotate integrally with the input member; and
a washer installed between an inner side surface of the side wall portion and the outer side surface of the one of the side gears,

wherein a through oil passage is formed in the intermediate wall portion of at least the one of the output gears, both ends of the through oil passage being respectively opened in an inner side surface and an outer side surface of the intermediate wall portion,
wherein an opening of the through oil passage is partially occluded by the washer, and
wherein

d
⁢

⁢

2
/
PCD

≦

3.36
·

(

1

z
⁢

⁢
1

)

2
3

·

sin
⁡

(

tan

-
1

⁢

z
⁢

⁢
1

z
⁢

⁢
2

)

 is satisfied, and
Z 1 /Z 2 >2 is satisfied, where Z 1 , Z 2 , d 2 and PCD denote the number of teeth of each of the output gears, the number of teeth of the differential gear, a diameter of the differential gear support portion and a pitch cone distance, respectively.

7. The differential device according to claim 6 , wherein Z 1 /Z 2 ≧4 is satisfied.

8. The differential device according to claim 6 , wherein Z 1 /Z 2 ≧5.8 is satisfied.

9. The differential device according to claim 6 , wherein relative positions of the washer and the through oil passage are set such that at least an inner peripheral portion of the washer faces the opening of the through oil passage opened to the outer side surface of the intermediate wall portion.

10. The differential device according to claim 6 , wherein a washer retaining groove, fitting and retaining the washer therein, is formed in at least one of the inner side surface of the side wall portion and the outer side surface of the output gear.

11. The differential device according to claim 9 , wherein the side wall portion includes a wei

Assignees

• Musashi Seimitsu Kogyo Kk

Inventors

• Mori Hiroyuki
• Nishimura Naoya

Classifications

• F16H48/08

  comprising bevel gears · CPC title

• F16H57/043

  within rotary parts, e.g. axial channels or radial openings in shafts · CPC title

• F16H57/0427

  on rotary parts, e.g. using baffles for collecting lubricant by centrifugal force · CPC title

• F16H57/0483 Primary

  Axle or inter-axle differentials · CPC title