Single pivot front derailleur
AssigneeWick Werks, LLC
InventorsChristopher A. Wickliffe, Eldon L. Goates
Life of this patent
Estimating the term…
Abstract
Embodiments of a front derailleur gear shifting system including various unique chain guides attached to and operating from a single pivot point. This derailleur system provides a simple, yet, elegant and robust improvement in shifting technique over conventional, lateral motion front derailleurs. Embodiments of open and closed annulus chain guides having specially shaped lifting and pulling surfaces for acting upon a bicycle chain during shifting are also disclosed. Additionally, as an optional enhancement, a dual-sided chain catcher that prevents unintended over-shifts in either direction is disclosed.
Claims21
A single pivot front derailleur for shifting a bicycle chain between a small chainring and a large chainring, the front derailleur, comprising:
- a mounting mechanism for structurally securing the front derailleur to a bicycle frame;
- a movement mechanism connected to the mounting mechanism, the movement mechanism further comprising:
- an arm having a proximal end housing a single pivot, the arm rotating about a single pivot in a plane of rotation, the plane of rotation at an acute angle relative to any vertical plane of the bicycle frame;
- and
- a chain guide connected to a distal end of the arm, the chain guide configured for lifting up or pulling down on the bicycle chain during shifting.
A single pivot front derailleur for shifting a bicycle chain between a small chainring and a large chainring, the front derailleur, comprising:
- a mounting mechanism for securing the front derailleur to a bicycle frame structural member;
- an arm rotationally connected to the mounting mechanism through a single pivot located at a proximal end;
- and
- a chain guide connected to a distal end of the arm, the chain guide and arm configured to selectively rotate about the single pivot in a direction forward or backward relative to the mounting mechanism during shifting.
A front derailleur for shifting a bicycle chain between a small chainring and a large chainring, the front derailleur, comprising:
- a chain guide having an upwardly and outwardly angled and contoured lifting surface and an inwardly and downwardly angled outer pulling surface for engaging the bicycle chain during up-shifts and down-shifts, respectively;
- an arm connected at a distal end to the chain guide, the arm housing a pivot axis about which the distal end and the chain guide rotate about;
- and
- a mounting mechanism rotationally connected to the arm through a single pivot housing the pivot axis.
A dual-sided chain catcher adjustably connected to a structural member of a bicycle frame, the dual-sided chain catcher comprising an inner guard and an outer guard, the inner guard preventing the bicycle chain from falling inside the small chainring during down-shifts and the outer guard preventing the bicycle chain from falling outside the large chainring during up-shifts.
Dependencies are inferred from the claim text.