Electromechanical rear derailleur for coaxial mounting

1. An electromechanical rear derailleur for coaxial mounting on a rear wheel axis of a bicycle, comprising:

a base member, the base member releasably mounted on a bicycle frame;

a movable member;

a chain guiding arrangement connected to the movable member for rotation about an axis of rotation;

a pivot mechanism connecting the base member to the movable member such that the movable member is movable relative to the base member; and

an electromechanical drive for driving the pivot mechanism,

wherein the base member includes a first connection end and a second connection end, the first connection end for coaxial mounting on the rear wheel axis, and the second connection end for coupling with the pivot mechanism,

a power source having a midplane, in the state mounted on the bicycle frame the midplane lies approximately in a plane with a right dropout,

wherein the electromechanical drive is received in a gear housing, and the gear housing has an electrical interface to directly attach a power source to the gear housing.

2. The electromechanical rear derailleur of claim 1 , wherein the first connection end of the base member is connected to the base member in a rotationally secure manner, and formed in one piece therewith.

3. The electromechanical rear derailleur of claim 2 , wherein the first connection end has at least one arm with a centring opening.

4. The electromechanical rear derailleur of claim 2 , wherein the first connection end of the base member has a first arm and a second arm arranged spaced apart from one another in the axial direction, the first arm has a first centring opening, and the second arm has a second centring opening.

5. The electromechanical rear derailleur of claim 4 , wherein, in the mounted state, the first arm is located on an axial inner side of the bicycle frame and the second arm is located on an axial outer side of the bicycle frame.

6. The electromechanical rear derailleur of claim 1 , wherein the second connection end of the base member has a first pin receiver for a first pivot pin of the pivot mechanism and a second pin receiver for a second pivot pin of the pivot mechanism.

7. The electromechanical rear derailleur of claim 6 , wherein the first pin receiver and the second pin receiver are each oriented substantially orthogonally to the rear wheel axis.

8. The electromechanical rear derailleur according to claim 6 , wherein the first and second pin receivers are each oriented at an angle relative to the rear wheel axis.

9. The electromechanical rear derailleur of claim 1 , further comprising:

an adapter, wherein the adapter connects the base member to the bicycle frame, the adapter includes a screw connection, the screw connection being a bolt with an external thread and a nut with an internal thread.

10. The electromechanical rear derailleur of claim 1 , wherein the electromechanical drive is arranged in a first region of the base member.

11. The electromechanical rear derailleur of claim 10 , wherein the electromechanical drive is a worm gear, and a motor-operated worm thereof is arranged in part in the first region of the base member, and cooperates with a worm wheel on the pivot mechanism.

12. The electromechanical rear derailleur of claim 11 , the base member defines a housing cavity in which the gear housing is arranged at least in part.

13. The electromechanical rear derailleur of claim 12 , wherein the base member is in a multi-part form and includes at least a first base sub-member for mounting on a bicycle frame and a second base sub-member for mounting on the first base sub-member, and the housing cavity is defined between the first and second base sub-member.

14. The electromechanical rear derailleur of claim 13 , wherein the first base sub-member comprises the first connection end of the base member having a first arm and a second arm.

15. An electromechanical rear derailleur for coaxial mounting on a rear wheel axis of a bicycle, comprising:

a base member, the base member releasably mounted on a bicycle frame and having a first connection end and a second connection end, the first connection end for coaxial mounting on the rear wheel axis;

a movable member;

a chain guiding arrangement connected to the movable member for rotation about an axis of rotation;

a pivot mechanism connecting the base member to the movable member such that the movable member is movable relative to the base member, the second connection end of the base member coupling with the pivot mechanism;

an electromechanical drive for driving the pivot mechanism; and

a power source having a midplane that runs between a first arm and a second arm of first connection end of the base member, and a midplane of the power source, in the state mounted on the bicycle frame, lies approximately in a plane with a right dropout.

16. An electromechanical rear derailleur for coaxial mounting on a rear wheel axis of a bicycle, comprising:

a base member, the base member releasably mounted on a bicycle frame;

a movable member;

a chain guiding arrangement connected to the movable member for rotation about an axis of rotation;

a pivot mechanism connecting the base member to the movable member such that the movable member is movable relative to the base member;

an electromechanical drive for driving the pivot mechanism; and

a power source having a midplane, in the state mounted on the bicycle frame the midplane lies approximately in a plane with a right dropout,

wherein the base member includes a first connection end and a second connection end, the first connection end for coaxial mounting on the rear wheel axis, and the second connection end for coupling with the pivot mechanism,

wherein the base member is configured to be fastened to the power source in a manner that electrically connects the power source to the electromechanical drive, and

wherein an electrical interface between the power source and the base member is positioned inboard of the base member.