Derailleur of a bicycle gearshift and method for electronically controlling a bicycle gearshift

Patent metadata

Field	Value
Publication number	US-9758217-B2
Application number	US-201514955935-A
Country	US
Kind code	B2
Filing date	Dec 1, 2015
Priority date	Dec 2, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A bicycle derailleur for operating a chain guide. The derailleur has primary actuator that imparts a primary displacement on the chain guide that has at least a component in an axial direction with respect to an assembly of toothed wheels. The derailleur also has secondary actuator that imparts a secondary displacement on the chain guide that has at least a component in a radial direction with respect to the assembly of toothed wheels. The secondary actuator can operate independently of the primary actuator.

First claim

What is claimed is:

1. A derailleur of a bicycle gearshift, comprising:
a support unit, configured to be mounted on a bicycle frame at an assembly of coaxial toothed wheels, the support unit includes a first fixing unit that has a support body and a chain tensioning spring being rotatably assembled on a pivot;
a mobile unit, comprising a chain guide;
a primary actuation means configured to move the mobile unit with respect to the support unit so as to impart onto the chain guide a primary displacement having at least a component in an axial direction with respect to an axis (Z) of the assembly of toothed wheels; and,
a secondary actuation means configured to move the mobile unit with respect to the support unit so as to impart onto the chain guide a secondary displacement having at least a component in a radial direction with respect to the axis (Z) of the assembly of toothed wheels,
wherein the secondary actuation means are capable of moving the mobile unit independently of the primary actuation means and the secondary actuation means comprise a linkage for adjusting a preload of the chain tensioning spring, and
the first fixing unit comprising a first ring rotatably mounted on the pivot, provided with a tooth for resting on the bicycle frame and with a seat in engagement with a first end of the chain tensioning spring; and,
the linkage for adjusting the preload of the chain tensioning spring comprises:
a second ring rotatably assembled in the support body and on the pivot, provided with a seat in engagement with a second end of the chain tensioning spring;
a toothed sector formed on the second ring; and,
a worm screw in engagement with the toothed sector.

2. The derailleur according to claim 1 , wherein:
the mobile unit comprises a mobile body and a second fixing unit, for assembling the chain guide on the mobile body;
the chain tensioning spring is provided in at least one of the first fixing unit and the second fixing unit, the chain tensioning spring determining a configuration of the chain guide when engaged with a bicycle transmission chain;
the linkage of the secondary actuation means determines a variation of the configuration of the chain guide that involves the secondary displacement of the chain guide.

3. The derailleur according to claim 2 , wherein the derailleur is of an articulated parallelogram type, with one fixed side and one mobile side opposite to the fixed side and connected to it by two connecting rods of equal length, wherein the fixed side is formed by the support body and the mobile side is formed by the mobile body.

4. The derailleur according to claim 2 , wherein:
the second fixing unit comprises:
a pivot assembled in the mobile body, the chain guide and the chain tensioning spring being rotatably assembled on the pivot; and
a seat formed in the chain guide, in engagement with a first end of the spring;

and,
the linkage for adjusting the preload of the chain tensioning spring comprises:
a ring rotatably assembled in the mobile body and provided with a seat in engagement with a second end of the chain tensioning spring;
a toothed sector formed on the ring; and
a worm screw in engagement with the toothed sector.

5. The derailleur according to claim 1 , wherein the primary actuation means comprise a first electric motor and the secondary actuation means comprise a second electric motor.

6. The derailleur according to claim 1 , wherein:
the primary actuation means and the secondary actuation means comprise a single shared electric motor; and,
a transmission is provided for having a primary output and a secondary output respectively associated with the primary actuation means and with the secondary actuation means.

7. The derailleur according to claim 6 , wherein the transmission comprises:
a primary shaft set in rotation by the single electric motor,
a primary toothed wheel fixedly fitted on the primary shaft,
a first secondary shaft and a second secondary shaft parallel to one another and to the primary shaft,
a first secondary toothed wheel fixedly fitted on the first secondary shaft,
a second secondary toothed wheel fixedly fitted on the second secondary shaft,
an auxiliary toothed wheel assembled in an axially mobile manner along an auxiliary axis (A) parallel to the primary and secondary shafts in meshed engagement permanently with the primary toothed wheel and selectively with one and/or the other of the secondary toothed wheels.

8. The derailleur according to claim 7 , wherein a reduction stage is arranged between the electric motor and the primary shaft.

9. The derailleur according to claim 7 , wherein the auxiliary toothed wheel is fixedly fitted onto an auxiliary shaft, rotatably carried by a slide guided in a mobile manner along the auxiliary axis (A).

10. The derailleur according to claim 9 , wherein said slide is actuated by an electromagnetic actuator.

11. The derailleur according to claim 10 , wherein the electromagnetic actuator comprises a push-pull electromagnet.

12. A derailleur of a bicycle gearshift, comprising:
a support, configured to be mounted on a bicycle frame at an assembly of coaxial toothed wheels, that supports a mobile chain guide, the support includes a first fixing unit that has a support body and a chain tensioning spring being rotatably assembled on a pivot;
a primary actuator for moving the chain guide through a primary displacement having a component in an axial direction with respect to an axis (Z) of the assembly of toothed wheels; and,
a secondary actuator for moving the chain guide through a secondary displacement having at least a component in a radial direction with respect to the axis (Z) of the assembly of toothed wheels,
wherein the secondary actuator is capable of moving the chain guide independently of the primary actuator and the secondary actuator comprises a linkage for adjusting a preload of the chain tensioning spring, and
the first fixing unit comprising a first ring rotatably mounted on the pivot, provided with a tooth for resting on the bicycle frame and with a seat in engagement with a first end of the chain tensioning spring; and,
the linkage for adjusting the preload of the chain tensioning spring comprises:
a second ring rotatably assembled in the support body and on the pivot, provided with a seat in engagement with a second end of the chain tensioning spring;
a toothed sector formed on the second ring; and,
a worm screw in engagement with the toothed sector.

13. The derailleur according to claim 12 , wherein the primary displacement is generally perpendicular to the second displacement.

Assignees

• Campagnolo Srl

Inventors

• Bortoli Alberto
• Bortolozzo Gianluca
• Pasqua Paolo

Classifications

• B62M9/122 Primary

  electrically or fluid actuated; Controls thereof · CPC title

• B62M9/124

  Mechanisms for shifting laterally · CPC title

• B62M9/132

  electrically or fluid actuated; Controls thereof · CPC title

• B62M2009/12413

  Rear derailleur comprising telescoping mechanisms · CPC title

• B62M9/134

  Mechanisms for shifting laterally · CPC title