Power transmission shaft

Patent metadata

Field	Value
Publication number	US-10533612-B2
Application number	US-201715634064-A
Country	US
Kind code	B2
Filing date	Jun 27, 2017
Priority date	Jul 11, 2016
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

A power transmission shaft comprises a shaft unit interposed between first and second shafts; an engaged portion provided on one end of the second shaft and having an annular stepped part provided between a smaller diameter portion and a larger diameter portion; and an engaging portion provided on one end of the shaft unit and joinable with the engaged portion to rotate together about a common rotation axis, wherein the engaging portion comprises a cylindrical base portion that rotates together with the shaft unit, an elastically shrinkable cylindrical portion that is provided on one axial end of the cylindrical base portion to project toward the engaged portion and catching pawls that are provided by the elastically shrinkable cylindrical portion and latchingly engageable with the annular stepped part when the engaged portion and the engaging portion are coaxially arranged and joined with each other.

First claim

What is claimed is:

1. A power transmission shaft interposed between first and second shaft members that make up a pair of vehicle side shaft members, the first shaft member being arranged to be driven by a power source and the second shaft member being arranged to drive road wheels, so that a power of the power source is transmitted to the road wheels through the power transmission shaft, the power transmission shaft comprising:
at least one shaft interposed between the first shaft member and the second shaft member;
an engaged portion that is provided on one axial end of one of the paired vehicle side shaft members and has an annular stepped part formed between a smaller diameter portion with a is first diameter and a larger diameter portion with a second diameter larger than the first diameter, each of the smaller and larger diameter portions being arranged to extend around a common rotation axis;
an engaging portion that is provided on one axial end of the at least one shaft, wherein the engaging portion comprises a cylindrical base portion that rotates together with the shaft unit, an elastically shrinkable cylindrical portion that is provided by the cylindrical base portion at a position opposite to the shaft unit, and a projected portion that is provided by the elastically shrinkable cylindrical portion; and
a fixing ring that is connectable to the engaging portion such that the projected portion is latchingly engaged with the annular stepped part when the elastically shrinkable cylindrical portion is subjected to shrink and/or expansion.

2. A power transmission shaft as claimed in claim 1 , in which the elastically shrinkable cylindrical portion is made of an elastic material and shrinkable and expandable within an elastic limit.

3. A power transmission shaft as claimed in claim 1 , further comprising an annular seal member that is provided between the second shaft member and the cylindrical base portion to seal a circular clearance defined therebetween.

4. A power transmission shaft as claimed in claim 3 , in which the elastically shrinkable cylindrical portion is formed with a slit portion that extends in the direction of the common rotation axis.

5. A power transmission shaft as claimed in claim 4 , in which the slit portion comprises a plurality of slits that are circumferentially arranged about the common rotation axis.

6. A power transmission shaft as claimed in claim 3 , in which a thickness in radial direction of the elastically shrinkable cylindrical portion is smaller than that of the cylindrical base portion.

7. A power transmission shaft as claimed in claim 6 , in which the annular seal member is axially spaced apart from the elastically shrinkable cylindrical portion by a given distance.

8. A power transmission shaft as claimed in claim 6 , in which the elastically shrinkable cylindrical portion is formed with a tapered portion whose thickness in radial direction gradually increases in the direction from the projected portion toward the cylindrical base portion.

9. A power transmission shaft as claimed in claim 1 , in which at least one of the elastically shrinkable cylindrical portion or the fixing ring is formed with a tapered portion whose radial dimension gradually changes in the direction of the common rotation axis, and in which when the fixing ring slides on the cylindrical base portion, the elastically shrinkable cylindrical portion is subjected to shrink and/or expansion due to a wedge effect produced by the tapered portion.

10. A power transmission shaft as claimed in claim 9 , in which the tapered portion is provided to both the elastically shrinkable cylindrical portion and the fixing ring, in which the fixing ring is arranged to exhibit the wedge effect when moving in the direction from the projected portion to the cylindrical base portion, and in which an angle of the tapered portion of the fixing ring relative to the common rotation axis is greater than an angle of the tapered portion of the elastically shrinkable cylindrical portion relative to the common rotation axis.

11. A power transmission shaft as claimed in claim 1 , further comprising a lock that is positionable between the engaging portion and the fixing ring to lock the fixing ring to the engaging portion.

12. A power transmission shaft as claimed in claim 11 , in which the lock is a circlip.

13. A power transmission shaft as claimed in claim 12 , in which the fixing ring is cylindrical and covers the engaging portion with a given annular clearance therebetween.

14. A power transmission shaft as claimed in claim 12 , in which the circlip is properly set between the engaging portion and the fixing ring only when the projected portion is latchingly engaged with the annular stepped part.

15. A power transmission shaft as claimed in claim 1 , in which the engaging portion is formed at an outer cylindrical wall thereof with a male screw portion and the fixing ring is formed at an inner cylindrical wall thereof with a female screw portion, so that when the male screw portion and the female screw portion are engaged, the fixing ring is fixed to the engaging portion.

16. A power transmission shaft as claimed in claim 15 , in which the projected portion is arranged to be viewed from outside when the fixing ring is fixed to the engaging portion.

17. A power transmission shaft as claimed in claim 1 , in which the fixing ring is formed with a first annular flange and the engaging portion is formed with a second annular flange, so that when the first and second annular flanges are combined by a given tool, the fixing ring is fitted to the engaging portion.

18. A power transmission shaft as claimed in claim 17 , in which at least one of the first or second annular flanges is formed with an annular sloped recess whose diameter gradually increases as the slope of the annular sloped recess is shifted radially outward.

19. A power transmission shaft as claimed in claim 1 , in which the projected portion is shaped to project radially inward toward the common rotation axis, in which the projected portion is formed with an inclined surface that is contactable with the annular stepped part, and in which a radial distance between the common rotation axis and the inclined surface gradually increases as an axial distance between the inclined surface and the annular stepped part reduces.

20. A power transmission shaft as claimed in claim 1 , in which the second shaft member is formed at its cylindrical outer surface with a male serration and the cylindrical base portion is formed at its cylindrical inner surface with a female serration that is engageable with the male serration, and in which when the male serration is inserted into the female serration by such a degree as to establish the deepest engagement therebetween, the projected portion is placed apart from the annular stepped part in the direction of the common rotation axis.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Sugiyama Kenichi
• Mabe Yasutomo

Classifications

• F16D2003/22326

  Attachments to the outer joint member, i.e. attachments to the exterior of the outer joint member or to the shaft of the outer joint member · CPC title

• F16D2003/22323

  Attachments to the shaft of the inner joint member whereby the attachments are distanced from the core · CPC title

• F16D2001/103

  the torque is transmitted via splined connections · CPC title

• F16D1/116

  the interengaging parts including a continuous or interrupted circumferential groove in the surface of one of the coupling parts (circlips for retaining hubs on shafts F16B21/18) · CPC title

• F16D3/223

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