Bicycle front derailleur

Patent metadata

Field	Value
Publication number	US-10252773-B2
Application number	US-201615279178-A
Country	US
Kind code	B2
Filing date	Sep 28, 2016
Priority date	Apr 5, 2016
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

A bicycle front derailleur is basically provided with a base member, a chain guide and a chain restricting abutment. The base member is configured to be mounted on a bicycle frame. The chain guide is configured to be movably coupled to the base member between a retracted position and an extended position to move a bicycle chain. The chain restricting abutment is configured to restrict the bicycle chain from moving in a radially outward direction of a rotational center axis of a bicycle front sprocket when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position.

First claim

What is claimed is:

1. A bicycle front derailleur comprising:
a base member configured to be mounted on a bicycle frame;
a chain guide configured to be movably coupled to the base member between a retracted position and an extended position to move a bicycle chain; and
a chain restricting abutment including a contact surface that contacts the bicycle chain to restrict the bicycle chain from moving in a radially outward direction of a rotational center axis of a bicycle front sprocket when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position.

2. The bicycle front derailleur according to claim 1 , wherein
the chain guide includes an inner guide plate and an outer guide plate, the outer guide plate including a base plate portion and a chain guiding portion protruding from the base plate portion toward the inner guide plate, the chain guiding portion being configured to contact a side surface of the bicycle chain when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position, a first axial distance defined between the chain restricting abutment and the inner guide plate being smaller than a second axial distance defined between the chain guiding portion and the inner guide plate.

3. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is disposed on a downstream side of the chain guiding portion with respect to a chain driving direction.

4. The bicycle front derailleur according to claim 1 , wherein
the chain guide includes an inner guide plate and an outer guide plate, the outer guide plate including a base plate portion and a chain guiding portion protruding from the base plate portion toward the inner guide plate, the chain guiding portion being configured to contact a side surface of the bicycle chain when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position, the outer guide plate is configured to define a non-contact space between the chain restricting abutment and the chain guiding portion in a chain driving direction, the non-contact space being configured not to contact the bicycle chain when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position.

5. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is disposed on the base member.

6. The bicycle front derailleur according to claim 5 , wherein
the chain restricting abutment is disposed at a front end of the base member.

7. The bicycle front derailleur according to claim 5 , wherein
the chain restricting abutment is disposed on a downwardly facing surface of the base member.

8. The bicycle front derailleur according to claim 7 , wherein
the chain guide includes an inner guide plate and an outer guide plate, and
the contact surface of the chain restricting abutment is part of a protrusion disposed between the inner guide plate and the outer guide plate as viewed from a direction perpendicular to the rotational center axis when the base member is mounted on the bicycle frame.

9. The bicycle front derailleur according to claim 1 , wherein
the chain guide includes an inner guide plate and an outer guide plate, and
the chain restricting abutment is disposed on an outer guide plate of the chain guide.

10. The bicycle front derailleur according to claim 9 , wherein
the chain restricting abutment is disposed forward of the inner guide plate.

11. The bicycle front derailleur according to claim 10 , wherein
the chain restricting abutment is integrally formed as a one-piece member of the outer guide plate.

12. The bicycle front derailleur according to claim 9 , wherein
the chain restricting abutment is disposed at a front end of the outer guide plate.

13. The bicycle front derailleur according to claim 12 , wherein
the outer guide plate includes a base plate portion and a chain guiding portion protruding from the base plate portion toward the inner guide plate, the chain guiding portion is configured to contact a side surface of the bicycle chain when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position, and the chain restricting abutment is aligned with the chain guiding portion in a direction extending parallel to a chain driving direction.

14. The bicycle front derailleur according to claim 1 , wherein
the chain guide includes an inner guide plate, an outer guide plate and a connecting part extending between the inner guide plate and the outer guide plate, the chain restricting abutment is disposed on the connecting part of the chain guide.

15. The bicycle front derailleur according to claim 14 , wherein
the chain restricting abutment is disposed at a front end of the chain guide.

16. The bicycle front derailleur according to claim 14 , wherein
the contact surface of the chain restricting abutment is part of a protrusion protruding from the connecting part between the inner guide plate and the outer guide plate.

17. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is configured to contact an outer periphery of the bicycle chain when the base member is mounted on the bicycle frame and the bicycle chain moves from a larger front sprocket toward an adjacent smaller front sprocket.

18. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is at least partially made of an elastic material.

19. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is configured to be elastically deformed by the bicycle chain that moves in the radially outward direction when the base member is mounted on the bicycle frame and the chain guide moves from the retracted position toward the extended position.

20. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is at least partially made of a non-metallic material.

21. The bicycle front derailleur according to claim 20 , wherein
the chain restricting abutment is at least partially made of a resin material.

22. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment is detachably connected to the base member.

23. A bicycle front derailleur according comprising:
a base member configured to be mounted on a bicycle frame;
a chain guide configured to be movably coupled to the base member between a retracted position and an extended position to move a bicycle chain; and
a chain restricting abutment configured to restrict the bicycle chain from moving in a radially outward direction of a rotational center axis of a bicycle front sprocket when the base member is mounted on the bicycle frame and the chain guide moves from the extended position toward the retracted position, the chain restricting abutment being at least partially made of an elastomer.

24. The bicycle front derailleur according to claim 1 , wherein
the chain restricting abutment includes an internal space.

25. The bicycle front derailleur according to claim 24 , wherein
the chain restricting abutment includes a through hole that comprises the internal space of the chain restricting abutment.

Assignees

• Shimano Kk

Inventors

• Inoue Kenkichi
• Sugimoto Akinobu

Classifications

• B62M9/105

  involving front sprocket chain-wheels engaged by the chain, belt or the like · CPC title

• B62M9/00

  Transmissions characterised by use of an endless chain, belt, or the like (cycle chain guards B62J13/00) · CPC title

• B62M9/135

  Mounting the derailleur on the frame · CPC title

• B62M9/136 Primary

  Chain guides; Mounting thereof · CPC title

• B62M9/134 Primary

  Mechanisms for shifting laterally · CPC title