Vehicular propeller shaft

Patent metadata

Field	Value
Publication number	US-10933741-B2
Application number	US-201815995464-A
Country	US
Kind code	B2
Filing date	Jun 1, 2018
Priority date	Jun 7, 2017
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A vehicular propeller shaft is configured to transmit a rotational force output from a drive force source to drive wheels. The vehicular propeller shaft includes a stepped pipe-shaped member including a compressive load weakest part with respect to an axial compressive load of the vehicular propeller shaft and a torsional load weakest part with respect to a torsional load around an axis of the vehicular propeller shaft. The compressive load weakest part and the torsional load weakest part are positioned apart from each other in a radial direction of the stepped pipe-shaped member.

First claim

What is claimed is:

1. A vehicular propeller shaft configured to transmit a rotational force output from a drive force source to drive wheels, the vehicular propeller shaft comprising:
a stepped pipe-shaped member including a compressive load weakest part with respect to an axial compressive load of the vehicular propeller shaft; and
a torsional load weakest part with respect to a torsional load around an axis of the vehicular propeller shaft, the compressive load weakest part and the torsional load weakest part being positioned apart from each other in a radial direction of the stepped pipe-shaped member, wherein:
the stepped pipe-shaped member includes
a small diameter pipe portion having a predetermined outer diameter,
a large diameter pipe portion having an outer diameter exceeding the outer diameter of the small diameter pipe portion, and
a first tapered pipe portion connecting the small diameter pipe portion and the large diameter pipe portion to each other;

the compressive load weakest part is positioned on the large diameter pipe portion side of the first tapered pipe portion; and
the torsional load weakest part is positioned on the small diameter pipe portion side of the first tapered pipe portion.

2. The vehicular propeller shaft according to claim 1 , wherein a groove-shaped circumferential direction notch disposed in an outer peripheral surface of the first tapered pipe portion on the large diameter pipe portion side constitutes the compressive load weakest part.

3. The vehicular propeller shaft according to claim 2 , wherein the stepped pipe-shaped member is configured to satisfy the following Formula 1 and Formula 2 in a plane including a center line of the vehicular propeller shaft,
0<1.95+0.0880× a+ 708× b− 96.7× c+ 232× d− 8.79× a×b+ 0.562× a×c+ 0.0150× a×d+ 188× b×c− 560× b×d− 1.0× c×d   1

0<−627+7.63× a+ 3,420× b− 18.6× c+ 8.84× d− 44.5× a×b+ 5.11× a×c+ 9.25× a×d− 402× b×c− 2,100× b×d− 728× c×d   2

in which a represents a first taper angle as an angle between the center line of the vehicular propeller shaft and a part of the first tapered pipe portion forming a straight line or a tangent to an inflection point in a curve portion of the first tapered pipe portion, b represents a pipe compression rate determined as 1−(small diameter pipe portion outer diameter/large diameter pipe portion outer diameter), c represents a pipe compression portion R rate determined as boundary portion radius/circumscribed radius, the boundary portion radius is a curvature radius of a boundary portion arc circumscribing a straight line showing an outer peripheral surface of the large diameter pipe portion and a curve showing the outer peripheral surface of the first tapered pipe portion, the circumscribed radius is a curvature radius of an arc circumscribing a first midpoint and a first contact point, the first midpoint is a midpoint between a base point and a first intersection point when an intersection point between the tangent to the first tapered pipe portion and an extension line of a straight line showing an outer peripheral surface of the small diameter pipe portion is the base point and an intersection point between the tangent to the first tapered pipe portion and an extension line of the straight line showing the outer peripheral surface of the large diameter pipe portion is the first intersection point, the first contact point is a point apart from the base point toward the outer peripheral surface of the small diameter pipe portion by a length from the base point to the first midpoint, and d represents a notch rate determined as a plate thickness of the circumferential direction notch/a plate thickness of the stepped pipe-shaped member other than the circumferential direction notch.

4. The vehicular propeller shaft according to claim 1 , wherein:
the stepped pipe-shaped member includes a medium diameter pipe portion having an outer diameter exceeding the outer diameter of the small diameter pipe portion and smaller than the outer diameter of the large diameter pipe portion and a second tapered pipe portion connecting the large diameter pipe portion and the medium diameter pipe portion to each other on the large diameter pipe portion side;
a second taper angle of the stepped pipe-shaped member is smaller than the first taper angle;
the first taper angle is an angle between the center line of the vehicular propeller shaft and the part of the first tapered pipe portion forming the straight line or the tangent to the inflection point in the curve portion of the first tapered pipe portion; and
the second taper angle is an angle between the center line of the vehicular propeller shaft and a part of the second tapered pipe portion forming a straight line or the tangent to the inflection point in a curve portion of the second tapered pipe portion.

Assignees

• Toyota Motor Co Ltd

Inventors

• Isono Tatsuya
• Kawarada Kouki
• Mori Atsushi
• Mikazuki Atsuo

Classifications

• B60K17/22 Primary

  characterised by arrangement, location, or type of main drive shafting, e.g. cardan shaft · CPC title

• F16C3/00 Primary

  Shafts (flexible shafts F16C1/00; marine propeller shafts, paddle wheel shafts B63H23/34); Axles; Cranks; Eccentrics · CPC title

• B60B2900/331

  Safety or security · CPC title

• B60B35/12

  Torque-transmitting axles (independent suspension aspects B60G) · CPC title

• F16C2240/30

  Angles, e.g. inclinations · CPC title