Sprocket support body and bicycle hub assembly

Patent metadata

Field	Value
Publication number	US-2020298619-A1
Application number	US-201916673981-A
Country	US
Kind code	A1
Filing date	Nov 5, 2019
Priority date	Mar 22, 2019
Publication date	Sep 24, 2020
Grant date	—

Abstract

A sprocket support body comprises an external spline configured to be engaged with an internal spline of a bicycle sprocket arrangement. The external spline includes a plurality of external-spline driving surfaces configured to transmit a rotational driving force between the sprocket support body and the bicycle sprocket arrangement in a circumferential direction. The plurality of external-spline driving surfaces includes at least four first external-spline driving surfaces and at least one second external-spline driving surface. The at least four first external-spline driving surfaces are respectively arranged on at least four of nine first external-spline driving positions equally arranged in the circumferential direction about a rotational center axis at a first external-spline pitch angle which is equal to 40 degrees. The at least one second external-spline driving surface is offset from the nine first external-spline driving positions in the circumferential direction about the rotational center axis.

First claim

What is claimed is:

1 . A sprocket support body for a bicycle hub assembly, comprising:
an external spline configured to be engaged with an internal spline of a bicycle sprocket arrangement, the external spline including a plurality of external-spline driving surfaces configured to transmit a rotational driving force between the sprocket support body and the bicycle sprocket arrangement in a circumferential direction with respect to a rotational center axis of the sprocket support body, the plurality of external-spline driving surfaces including
at least four first external-spline driving surfaces respectively arranged on at least four of nine first external-spline driving positions equally arranged in the circumferential direction about the rotational center axis at a first external-spline pitch angle which is equal to 40 degrees, and
at least one second external-spline driving surface offset from the nine first external-spline driving positions in the circumferential direction about the rotational center axis.

2 . The bicycle sprocket support body according to claim 1 , wherein
the at least four first external-spline driving surfaces include nine first external-spline driving surfaces, and the nine first external-spline driving surfaces are equally arranged in the circumferential direction about the rotational center axis at the first external-spline pitch angle.

3 . The sprocket support body according to claim 1 , wherein
the at least one second external-spline driving surface includes at least three second external-spline driving surfaces offset from the nine first external-spline driving positions in the circumferential direction about the rotational center axis.

4 . The sprocket support body according to claim 3 , wherein
the at least three second external-spline driving surfaces are equally arranged in the circumferential direction about the rotational center axis at a second external-spline pitch angle.

5 . The sprocket support body according to claim 4 , wherein
the at least three second external-spline driving surfaces include nine second external-spline driving surfaces equally arranged in the circumferential direction about the rotational center axis at the second external-spline pitch angle.

6 . The sprocket support body according to claim 4 , wherein
the second external-spline pitch angle is equal to 40 degrees.

7 . The sprocket support body according to claim 4 , wherein
the at least three second external-spline driving surfaces are offset from the nine first external-spline driving surfaces in the circumferential direction about the rotational center axis at a first external-spline offset angle smaller than the second external-spline pitch angle.

8 . The sprocket support body according to claim 7 , wherein
the first external-spline offset angle is equal to or smaller than a half of the second external-spline pitch angle.

9 . The sprocket support body according to claim 4 , wherein
the plurality of external-spline driving surfaces includes at least one third external-spline driving surface offset from the nine first external-spline driving positions and the at least three second external-spline driving surfaces in the circumferential direction about the rotational center axis.

10 . The sprocket support body according to claim 9 , wherein
the at least one third external-spline driving surface includes at least three third external-spline driving surfaces offset from the nine first external-spline driving surfaces and the at least three second external-spline driving surfaces in the circumferential direction about the rotational center axis.

11 . The sprocket support body according to claim 10 , wherein
the at least three third external-spline driving surfaces are equally arranged in the circumferential direction about the rotational center axis at a third external-spline pitch angle.

12 . The sprocket support body according to claim 11 , wherein
the third external-spline pitch angle is equal to 40 degrees.

13 . The sprocket support body according to claim 11 , wherein
adjacent two driving surfaces of the at least three third external-spline driving surfaces are equally arranged in the circumferential direction about the rotational center axis at an additional third external-spline pitch angle different from the third external-spline pitch angle.

14 . The sprocket support body according to claim 13 , wherein
the additional third external-spline pitch angle is larger than the third external-spline pitch angle.

15 . The sprocket support body according to claim 1 , wherein
the external spline includes a plurality of external-spline teeth.

16 . The sprocket support body according to claim 15 , wherein
the plurality of external-spline teeth includes
at least four first external-spline teeth respectively arranged on at least four of nine first external-spline tooth positions equally arranged in the circumferential direction about the rotational center axis at the first external-spline pitch angle, and
at least one second external-spline tooth offset from the nine first external-spline tooth positions in the circumferential direction about the rotational center axis,
the at least four first external-spline teeth respectively include the at least four first external-spline driving surfaces, and the at least one second external-spline tooth respectively includes the at least one second external-spline driving surface.

17 . The bicycle sprocket support body according to claim 16 , wherein
the at least four first external-spline teeth include nine first external-spline teeth, the at least four first external-spline driving surfaces include nine first external-spline driving surfaces, the nine first external-spline driving surfaces are equally arranged in the circumferential direction about the rotational center axis at the first external-spline pitch angle, and the nine first external-spline teeth respectively include the nine first external-spline driving surfaces.

18 . The sprocket support body according to claim 17 , wherein
the nine first external-spline teeth have the same cross-sectional shape as each other on a plane perpendicular to the rotational center axis.

19 . The sprocket support body according to claim 16 , wherein
the plurality of external-spline teeth has the same cross-sectional shape as each other on a plane perpendicular to the rotational center axis.

20 . The sprocket support body according to claim 16 , further comprising
a tubular body having the rotational center axis, wherein the plurality of external-spline teeth extends radially outwardly from the tubular body with respect to the rotational center axis.

21 . The sprocket support body according to claim 16 , wherein
the plurality of external-spline teeth defines a plurality of external-spline recesses, each recess of the plurality of external-spline recesses is provided between adjacent two teeth of the plurality of external-spline teeth in the circumferential direction, the plurality of external-spline recesses includes
a first external-spline recess having a first circumferential width defined in the circumferential direction, and
a second external-spline recess having a second circumferential width defined in the circumferential direction, and
the second circumferential width is different from the first circumferential width.

22 . The sprocket support body according to claim 1 , w

Assignees

• Shimano Kk

Inventors

• Oka Tomonari

Classifications

• B60B27/023

  specially adapted for bicycles · CPC title

• B62M9/10 Primary

  involving different-sized wheels, {e.g. rear sprocket chain wheels} selectively engaged by the chain, belt, or the like {(bicycle hubs rotatably arranged on axle B60B27/023)} · CPC title

• B60B27/04

  housing driving means, e.g. sprockets · CPC title

• F16H55/30

  Chain-wheels · CPC title

• F16D2001/103

  the torque is transmitted via splined connections · CPC title