BACKGROUND OF THE INVENTION

This invention relates to bicycles and bicycle derailleurs. In particular the invention relates to electromechanical rear derailleurs for bicycles.

SUMMARY OF THE INVENTION

The invention provides, in one aspect, an electromechanical rear derailleur for a bicycle, including a base member attachable to the bicycle along a mounting axis. A movable member includes a cage assembly attached thereto. A linkage includes pivot axes oriented substantially perpendicular to the mounting axis. The linkage coupling the movable member to the base member is operative to enable movement of the movable member relative to the base member in a direction substantially parallel to the mounting axis. A power source is provided with a motor electrically connected to the power source, and a transmission is coupled to and actuated by the motor to move the movable member.

Other aspects of the invention provide a rear derailleur wherein the power source is disposed on or in the base member. The linkage may include an outer link member and an inner link member. The linkage may include link pins on which the linkage pivots, the link pins defining the pivot axes. The transmission may include a plurality of gears rotatable about a plurality of gear axes, respectively, wherein the gear axes are substantially parallel to the pivot axes. The transmission may be disposed on or in the base member. The motor may be disposed on or in the base member. The power source may be disposed on or in the base member. The linkage may include an outer link member and an inner link member. The rear derailleur may further include a clutch between the movable member and the transmission, the clutch moving the movable member responsive to operation of the transmission. The clutch may include a drive arm coupled to the transmission and a clutch spring in contact with the drive arm. The transmission may include an output gear and the drive arm is coupled to the output gear. The clutch spring may be disposed on the inner link member. The clutch spring may be disposed about the link pin that attaches the inner link member to the movable member. The motor may have a motor shaft with a motor shaft axis that is perpendicular to the pivot axes. The linkage may include link pins on which the linkage pivots, the link pins defining the pivot axes, wherein the pivot axes are substantially parallel to the mounting axis and the transmission includes a plurality of gears rotatable about a plurality of gear axles, respectively, wherein at least some of the gear axles have gear axle axes that are substantially parallel to the pivot axes.

The invention also provides in an alternative embodiment an electromechanical rear derailleur for a bicycle, including a base member attachable to the bicycle. A movable member is provided having a cage assembly attached thereto. A linkage is provided coupling the movable member to the base member and operative to enable movement of the movable member relative to the base member. The derailleur includes a power source and a motor electrically connected to the power source. A transmission is coupled to and actuated by operation of the motor to move the movable member and a position detector is provided, including a magnet rotated by the transmission, a sensor to sense rotation of the magnet, a magnet guide sized and shaped to guidingly receive a portion of the magnet and position the magnet within an effective range of the sensor.

Alternatives include wherein the rear derailleur includes a magnet holder disposed in the rear derailleur, the magnet held by the magnet holder. The magnet holder may be coupled to the transmission. The rear derailleur may further include a PC board positioned in the base member and wherein the sensor is disposed on the PC board in position to sense motion of the magnet. A magnet guide may be disposed on the PC board and the magnet extends from the magnet holder. The magnet holder may be attached to a position detector gear. The position detector gear may be in contact with and actuated by an output gear of the transmission. The rear derailleur may further include a position detector gear biasing gear disposed in the derailleur and coupled to the position detector gear to reduce backlash thereof.

In an embodiment, an electromechanical rear derailleur for a bicycle includes a base member attachable to the bicycle, the base member having a housing with an opening. The derailleur also includes a moveable member having a cage assembly attached thereto, and a linkage coupling the moveable member to the base member and operative to enable movement of the moveable member relative to the base member. The derailleur also includes a power supply disposed on the base member; and a motor module configured to move the moveable member. The base member is configured to receive the motor module in the opening of the housing such that the motor module is disposed within the base member and electrically connected to the power supply.

In an embodiment, a rear derailleur for a bicycle includes a movable member having a cage assembly attached thereto, and a base member attachable to the bicycle along a mounting axis, the base member including a housing. The housing includes a wall configured for removable attachment to a power supply housing, an opening configured to receive a motor module therein, and a linkage attachment portion. The derailleur also includes a linkage attached to the base member at the linkage attachment portion, the linkage coupling the movable member to the base member and operative to enable movement of the movable member relative to the base member, the linkage configured to be moved by the motor module.

In an embodiment, an electromechanical rear derailleur for a bicycle is provided. The electromechanical rear derailleur includes a base member attachable to the bicycle, and a moveable member having a damper and a cage assembly attached thereto. The cage assembly is pivotally connected to the base member and including wheels configured to interact with a bicycle chain. The electromechanical rear derailleur also includes a linkage coupling the moveable member to the base member and operative to enable movement of the moveable member relative to the base member; and a power supply and motor module disposed on the base member, the motor module operatively coupled to the linkage and received in a housing. The power supply provides power to the motor module to move the wheels and damper relative to the base member.

These and other features and advantages of the present invention will be more fully understood from the following description of one or more embodiments of the invention, taken together with the accompanying drawings.

