Rear derailleur

Patent metadata

Field	Value
Publication number	US-11401006-B2
Application number	US-201916547236-A
Country	US
Kind code	B2
Filing date	Aug 21, 2019
Priority date	Aug 22, 2018
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

A bicycle derailleur mechanism is provided which accommodates larger radial spacing and/or smaller radial spacing having a non-uniform value over the respective winding region. The derailleur mechanism cable pull transmission device may provide over its rotational angular range about the rotational axis, which is effective during operation, a variable transmission ratio as a function of the rotational position of the cable pull transmission device relative to the base component.

First claim

I claim:

1. A derailleur mechanism for a rear wheel derailleur of a bicycle, comprising:
a base component which is configured to be immovably fastened to a bicycle relative to a bicycle frame during its intended gear shift operation,
a movement coupling device and a chain guide arrangement which is displaceably coupled to the base component by means of the movement coupling device in a translatory manner relative to the base component,
a cable pull securing formation which is configured for supporting a cable sheath and for passing a cable of a gear shift cable pull portion through the cable pull securing formation running from a gear shift actuating device to the derailleur mechanism, and
a cable pull transmission device which is rotatably arranged about a rotational axis on the base component,
wherein the cable pull transmission device has a gear shift deflection contour which surrounds the rotational axis with a larger radial spacing and has a displacement deflection contour which surrounds the rotational axis with a smaller radial spacing, wherein the gear shift deflection contour and the displacement deflection contour are connected together for common rotational movement about the rotational axis,
wherein the gear shift deflection contour is configured to receive the gear shift cable pull portion so as to bear along a gear shift winding region and the displacement deflection contour is configured to receive a displacement cable pull portion running between the displacement deflection contour and the movement coupling device so as to bear along a displacement winding region, and
wherein in that the larger radial spacing or the smaller radial spacing has a non-uniform value over the respective winding region, so that the cable pull transmission device, over its rotational angular range about the rotational axis which is effective during operation, provides a variable transmission ratio as a function of the rotational position of the cable pull transmission device relative to the base component.

2. The derailleur mechanism of claim 1 , wherein the displacement deflection contour extends eccentrically about the rotational axis such that the smaller radial spacing of the displacement deflection contour, starting from a minimum displacement winding region, with an increasing winding angle of the displacement winding region reduces to a minimum value of the smaller radial spacing, and starting therefrom becomes larger again.

3. The derailleur mechanism of claim 2 , wherein the location of the minimum value of the smaller radial spacing is located closer to a longitudinal end of the displacement winding region located more remotely from the movement coupling device than to the longitudinal end of the displacement winding region located closer to the movement coupling device.

4. The derailleur mechanism of claim 2 , wherein the movement coupling device comprises a parallelogram connecting rod gear system with two parallelogram connecting rods which in each case have an articulated region on the base component side and an articulated region on the chain guide side, wherein each parallelogram connecting rod is pivotably connected to the base component at its articulated region on the base component side about a base-connecting rod axis, and is pivotably connected to the chain guide arrangement at its articulated region on the chain guide side about a chain guide connecting rod axis,
wherein the derailleur mechanism has a cam disc which is connected to one of the parallelogram connecting rods as a master connecting rod for common movement, wherein the cam disc is configured to guide a cable end of the displacement cable pull portion, coupled to the master connecting rod for common movement, away from the master connecting rod along a bearing region so as to bear against a bearing track configured on the cam disc.

5. The derailleur mechanism of claim 4 , further comprising the displacement cable pull portion which couples the master connecting rod to the displacement deflection contour for common movement, wherein for at least half of the common movement range of the cam disc and the displacement deflection contour it applies that a cable length of the displacement cable pull portion, freely running between the cam disc and the displacement deflection contour, runs independently of the respective operating rotational position of the cam disc and the displacement deflection contour both tangentially to the bearing track of the cam disc and tangentially to the displacement deflection contour.

6. The derailleur mechanism of claim 5 , wherein the cam disc and the displacement deflection contour are planar structures having extension planes oriented at right-angles to their respective rotational movement axis, wherein their extension planes enclose an angle between 65° and 90°.

7. The derailleur mechanism of claim 6 , wherein their extension planes enclose an angle of between 70° and 80°.

8. The derailleur mechanism of claim 4 , wherein the cam disc is rotatably mounted on a receiving component consisting of the base component and the chain guide arrangement by means of a bearing component defining a connecting rod axis of the master connecting rod for common rotation with the master connecting rod about the connecting rod axis, wherein the cam disc is preferably arranged axially relative to the connecting rod axis between a portion of the base component and the master connecting rod.

9. The derailleur mechanism of claim 8 , further comprising a component consisting of the master connecting rod and the receiving component has an apron which protrudes along the connecting rod axis and which runs about the connecting rod axis and which surrounds a bearing formation of the cam disc encompassing the bearing component radially outwardly relative to the connecting rod axis.

10. The derailleur mechanism of claim 4 , wherein the cam disc has a recess which is passed through by a further bearing component which defines a connecting rod axis of the other respective connecting rod of the parallelogram connecting rod gear system, which is not the master connecting rod, wherein the further bearing component together with an edge portion of the recess forms a mechanical end stop for limiting the rotational movement of the cam disc in at least one rotational direction.

11. The derailleur mechanism of claim 4 , wherein the base component has a fastening formation for fastening to the bicycle, which defines a fastening axis along which a fastening component that is a screw or a wheel axle, extends for fastening the base component to the bicycle, wherein the connecting rod axes have a spacing from the fastening axis which is different from zero and with the fastening axis enclose an angle ranging from 75° to 105°.

12. The derailleur mechanism of claim 1 , wherein the cable pull securing formation is pivotably arranged about a rocker axis relative to the base component.

13. The derailleur mechanism of claim 12 , further comprising a cable channel component which relative to the base component is immovably secured thereto and which together with the gear shift deflection contour forms a cable channel for a part of the gear shift cable pull portion received on the gear shift winding region, wherein the cable pull securing formation is pivotably mounted on the cable channel component.

14. The derailleur mechanism of claim 13 , wherein the rocker axis is oriented parallel to the rotational axis.

15. The derailleur mechanism of claim 13 , wherein the rocker axis passes through the cable channel.

16. The derailleur mechanism of one of claim 1 ,

Assignees

• Sram De Gmbh

Inventors

• Braedt Henrik

Classifications

• B62M9/124

  Mechanisms for shifting laterally · CPC title

• B62M9/126

  Chain guides; Mounting thereof · CPC title

• B62M9/127 Primary

  Mounting or guiding of cables · CPC title

• B62M25/02

  with mechanical transmitting systems, e.g. cables, levers · CPC title

• B62M9/125

  Mounting the derailleur on the frame · CPC title