Bicycle crank assembly

Patent metadata

Field	Value
Publication number	US-10000253-B1
Application number	US-201615361332-A
Country	US
Kind code	B1
Filing date	Nov 25, 2016
Priority date	Nov 25, 2016
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

A crank arm fixing ring is basically provided with a cylindrical mounting portion and a contact portion. The cylindrical mounting portion includes an external thread configured to screw into a crankshaft. The contact portion extends radially outwardly from the cylindrical mounting portion. The contact portion is configured to contact a crank arm upon attachment of the crank arm with the crank arm fixing ring. The contact portion includes at least one cutout extending radially outwardly from the cylindrical mounting portion. The at least one cutout is configured to receive a transmission line extending through the cylindrical mounting portion.

First claim

What is claimed is:

1. A crank arm fixing ring comprising:
a cylindrical mounting portion including an external thread configured to screw into a crankshaft, the cylindrical mounting portion having a first end and a second end; and
a contact portion including at least one tool engagement protrusion extending axially from the second end of the cylindrical mounting portion and extending radially outwardly with respect to the second end of the cylindrical mounting portion, the at least one tool engagement protrusion being configured to contact a crank arm upon attachment of the crank arm with the crank arm fixing ring, the contact portion including at least one cutout extending axially and radially outwardly from the second end of the cylindrical mounting portion and configured to receive a transmission line extending through the cylindrical mounting portion.

2. The crank arm fixing ring according to claim 1 , wherein
the at least one cutout of the contact portion includes a plurality of the cutouts.

3. The crank arm fixing ring according to claim 2 , wherein
the at least one tool engagement protrusion includes a plurality of tool engagement protrusions and the cutouts are arranged to define the plurality of tool engagement protrusions.

4. The crank arm fixing ring according to claim 3 , wherein
the tool engagement protrusions are equally spaced apart in a circumferential direction.

5. The crank arm fixing ring according to claim 3 , wherein
at least two of the tool engagement protrusions are diametrically disposed.

6. The crank arm fixing ring according to claim 1 , wherein
the cylindrical mounting portion and the contact portion are integrally formed as a one-piece member.

7. The crank arm fixing ring according to claim 1 , wherein
the cylindrical mounting portion and the contact portion are made of a metallic material.

8. The crank arm fixing ring according to claim 1 , wherein
the cylindrical mounting portion and the contact portion are made of a non-metallic material.

9. A bicycle crank assembly comprising:
a crankshaft having a first end portion and a second end portion, the second end portion having an opening with an internal thread, the opening leading to an interior space of the crankshaft;
a crank arm including a crankshaft receiving opening with the second end portion of the crankshaft disposed in the crankshaft receiving opening;
a crank arm fixing ring securing the crank arm to the second end portion of the crankshaft, the crank arm fixing ring comprising:
a cylindrical mounting portion including an external thread screwed into the internal thread of the crankshaft; and
a contact portion contacting the crank arm, the contact portion including at least one cutout extending radially outwardly from the cylindrical mounting portion; and

a transmission line extending into the cylindrical mounting portion of the crank arm fixing ring and out of the cylindrical mounting portion of the crank arm fixing ring via the at least one cutout.

10. The bicycle crank assembly according to claim 9 , further comprising
a first electrical unit disposed in the interior space of the crankshaft; and
a second electrical unit disposed on the crank arm, the first electrical unit being electrically connected to the second electrical unit by the transmission line.

11. The bicycle crank assembly according to claim 10 , wherein
the crank arm has an internal cavity and the transmission line extends into the internal cavity of the crank arm.

12. The bicycle crank assembly according to claim 11 , wherein
the crank arm has a bore extending from the internal cavity to the crankshaft receiving opening, the transmission line extends through the bore.

13. The bicycle crank assembly according to claim 12 , further comprising
an outer cap disposed in the crankshaft receiving opening and concealing the crank arm fixing ring and a portion of the transmission line extending out of the bore and into an area of the crankshaft receiving opening.

14. The bicycle crank assembly according to claim 9 , further comprising
an additional crank arm secured to the first end portion of the crankshaft.

15. The bicycle crank assembly according to claim 14 , wherein
the additional crank arm includes a sprocket mounting structure with at least one sprocket mounted on the sprocket mounting structure.

16. The bicycle crank assembly according to claim 9 , wherein
the at least one cutout of the contact portion includes a plurality of the cutouts.

17. The bicycle crank assembly according to claim 16 , wherein
the cutouts are arranged to define a plurality of tool engagement protrusions.

18. The bicycle crank assembly according to claim 17 , wherein
the tool engagement protrusions are equally spaced apart in a circumferential direction.

19. The bicycle crank assembly according to claim 1 , wherein
the cylindrical mounting portion and the contact portion are integrally formed as a one-piece member.

Assignees

• Shimano Kk

Inventors

• Tetsuka Toshio
• Furuya Takashi
• Mori Shintaro

Classifications

• F16B23/0061

  with grooves, notches or splines on the external peripheral surface designed for tools engaging in radial direction (F16B23/003 takes precedence) · CPC title

• F16B9/054

  the intermediate member being threaded · CPC title

• B62M3/16

  Accessories · CPC title

• B62M25/08

  with electrical or fluid transmitting systems · CPC title

• F16B23/00

  Specially shaped {nuts or} heads of bolts or screws for rotations by a tool {(detachable ornamental heads for screws A47G3/00; screwdrivers, wrenches B25B)} · CPC title