Power transfer structure of vehicle

Patent metadata

Field	Value
Publication number	US-10023049-B2
Application number	US-201515320715-A
Country	US
Kind code	B2
Filing date	Jun 24, 2015
Priority date	Jun 26, 2014
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

In a transfer structure of a vehicle according to one aspect of the present invention, a drive shaft includes: a first power transfer shaft including a first end coupled to a differential device; a second power transfer shaft including a first end coupled to a second end of the first power transfer shaft through a first universal joint; and a third power transfer shaft including a first end coupled to a second end of the second power transfer shaft through a second universal joint and a second end to which a driving wheel is coupled, and dampers are provided on at least two respective power transfer shafts. Among these dampers, a predetermined damper arranged on the longest power transfer shaft out of the at least two power transfer shafts functions in a frequency region lower than a frequency region in which a remaining damper functions.

First claim

The invention claimed is:

1. A power transfer structure of a vehicle, the power transfer structure comprising:
a power source including a differential device; and
a drive shaft coupling the differential device and a driving wheel, wherein:
the drive shaft includes:
a first power transfer shaft including a first end thereof coupled to the differential device,
a second power transfer shaft including a first end thereof coupled to a second end of the first power transfer shaft through a first universal joint, and
a third power transfer shaft including a first end thereof coupled to a second end of the second power transfer shaft through a second universal joint and a second end to which the driving wheel is coupled;

dampers are provided on at least two of the first, second, and third power transfer shafts; and
among these dampers, a first damper arranged on a longest one of the at least two power transfer shafts functions in a first frequency region lower than a second frequency region in which a second damper functions.

2. The power transfer structure according to claim 1 , wherein:
the power source includes an engine to which an exhaust pipe is connected;
the exhaust pipe is provided so as to extend through a position above the first power transfer shaft of the drive shaft; and
the first damper is a metal damper provided on the first power transfer shaft, the metal damper including a small-diameter portion formed in a predetermined range in an axial direction and being configured to damp vibrations by torsion of the small-diameter portion.

3. The power transfer structure according to claim 2 , wherein the second damper includes a rubber member that damps the vibrations and is provided on at least one of the second power transfer shaft and the third power transfer shaft.

4. The power transfer structure according to claim 1 , wherein:
the second power transfer shaft includes:
a fourth power transfer shaft including a first end thereof coupled to the first universal joint and a second end extending toward the second universal joint,
a fifth power transfer shaft including a second end thereof coupled to the second universal joint and a first end of the fifth power transfer shaft extending toward the first universal joint, and
an elastic damper configured such that a tubular portion provided at one of the second end of the fourth power transfer shaft and the first end of the fifth power transfer shaft accommodates a shaft portion provided at the other of the second end of the fourth power transfer shaft and the first end of the fifth power transfer shaft, and an elastic member is interposed between the tubular portion and the shaft portion; and

in an axial direction, a portion of the elastic damper located at a second universal joint side of the elastic member is a small-diameter portion that is smaller in diameter than each of a first portion of the elastic damper where the elastic member is provided and a second portion of the elastic damper located at a first universal joint side of the elastic member.

5. The power transfer structure according to claim 4 , wherein a first distance between the elastic damper and the first universal joint in the axial direction is shorter than a second distance between the elastic damper and the second universal joint in the axial direction.

6. The power transfer structure according to claim 5 , wherein the small-diameter portion is provided with a restricting portion configured to restrict relative rotation of the tubular portion and the shaft portion within a predetermined angular range.

7. The power transfer structure according to claim 6 , wherein the elastic damper includes a first bearing located at the first universal joint side of the elastic member in the axial direction and interposed between the tubular portion and the shaft portion.

8. The power transfer structure according to claim 7 , wherein:
the elastic damper includes a second bearing located at the second universal joint side of the elastic member in the axial direction and interposed between the tubular portion and the shaft portion; and
the second bearing is smaller in diameter than the first bearing.

9. The power transfer structure according to claim 1 , wherein:
the second power transfer shaft includes:
a fourth power transfer shaft including a first end thereof coupled to the first universal joint and a second end of the fourth power transfer shaft extending toward the second universal joint, and
a fifth power transfer shaft including a second end thereof coupled to the second universal joint and a first end of the fifth power transfer shaft extending toward the first universal joint, and
an elastic damper configured such that a tubular portion provided at one of the second end of the fourth power transfer shaft and the first end of the fifth power transfer shaft accommodates a shaft portion provided at the other of the second end of the fourth power transfer shaft and the first end of the fifth power transfer shaft, and an elastic member is interposed between the tubular portion and the shaft portion; and

the elastic damper includes:
a first bearing located at an opening portion side of the elastic member in an axial direction and interposed between an outer periphery of the shaft portion and an inner periphery of the tubular portion,
a diameter-expanded portion located at a side opposite to the opening portion side of the first bearing in the axial direction and projecting outward in a radial direction from the outer periphery of the shaft portion, and
a retaining portion located at the opening portion side of the first bearing in the axial direction and projecting inward in the radial direction from the inner periphery of the tubular portion; and

a pull-out strength of the elastic damper by the retaining portion is higher than a pull-out strength of the first universal joint.

10. The power transfer structure according to claim 9 , wherein the first universal joint includes:
an accommodated portion provided at the first end of the fourth power transfer shaft;
a tube-shaped portion provided at the second end of the first power transfer shaft so as to accommodate the accommodated portion; and
a boot portion provided on an outer periphery of the tube-shaped portion and an outer periphery of the fourth power transfer shaft so as to be extendable in the axial direction.

11. The power transfer structure according to claim 10 , wherein:
the power source includes an engine;
the retaining portion is constituted by a snap ring attached to a circumferential groove so as to be reduced in diameter, the circumferential groove being formed on the inner periphery of the tubular portion;
the elastic damper is arranged behind the engine in a vehicle forward/rearward direction and outside the first universal joint in a vehicle width direction;
the tubular portion is arranged so as to extend outward in the vehicle width direction from the first end of the fourth power transfer shaft; and
the opening portion is arranged outside the engine in the vehicle width direction.

12. The power transfer structure according to claim 11 , wherein:
in addition to the first bearing arranged at the opening portion side of the elastic member in the axial direction, the elastic damper further includes a second bearing arranged at a side opposite to the opening portion side of the elastic member in the axial direction; and
the first bearing is larger in diameter than the second bearing.

13. The power transfer structure according to claim 4 , wherein the small-diameter portion is provided with a restricting portion configured to restrict re

Assignees

• Mazda Motor

Inventors

• Nishimura Kenichiro
• Mito Eiji

Classifications

• F16D3/845

  allowing relative movement of joint parts due to the flexing of the cover · CPC title

• F16D3/227

  the joints being telescopic · CPC title

• F16D2300/22

  Vibration damping · CPC title

• F16D3/223

  the rolling members being guided in grooves in both coupling parts · CPC title

• F16F15/12

  using elastic members or friction-damping members, e.g. between a rotating shaft and a gyratory mass mounted thereon ({F16F15/14} , F16F15/16 take precedence) · CPC title