Rear wheel hub such as star ratchet useful in an impeller for a bicycle e.g. a mountain bike, comprises a hub body, an axle body, a first bearing device between the hub body and the axle body, and a freewheel body for receiving a bicycle

摘要

The rear wheel hub (10) comprises a hub body (12), an axle body (14), a first bearing device (16) between the hub body and the axle body, where the hub body is rotatably held in relation to the axle body around a rotational axis, a freewheel body (18) for receiving a bicycle, a second bearing device (20) between the axle body and the freewheel body, where the freewheel body is rotatably held in relation to the axle body around the rotational axis, and a freewheel device between the freewheel and hub bodies, where the freewheel device causes a coupling between the freewheel and hub bodies. The rear wheel hub (10) comprises a hub body (12), an axle body (14), a first bearing device (16) between the hub body and the axle body, where the hub body is rotatably held in relation to the axle body around a rotational axis, a freewheel body (18) for receiving a bicycle, a second bearing device (20) between the axle body and the freewheel body, where the freewheel body is rotatably held in relation to the axle body around the rotational axis, and a freewheel device between the freewheel body and the hub body, where the freewheel device causes a coupling between the freewheel body and the hub body in a first rotational direction around the rotational axis. The freewheel body is freely rotatable against the hub body in a second direction, which is opposite to the first direction. The freewheel device has a first front wheeling and a second front wheeling, which are turned towards each other and are axially movable to each other and of which one is rigidly formed in relation to the hub body and the other is formed in relation to the freewheel body. The first bearing device has a first hub bearing and a second hub bearing, where each hub bearing has an inner ring and an outer ring and each hub bearing is held at one side with the inner ring axially in a first holding direction in relation to the hub axis. Each hub bearing is held at one side with the outer ring in a second holding direction, which is opposite to the first holding direction, in relation to the hub body. The first holding direction of the second hub bearing runs opposite to the first holding direction of the first hub bearing. The second bearing device has first and second freewheel bearings. Each freewheel bearing has an inner ring and an outer ring. Each freewheel bearing is held at one side with the inner ring axially in a first holding direction in relation to the hub axis, is held at one side with the outer ring in a second holding direction, which is opposite to the first holding direction, in relation to the freewheel body. The first holding direction of the second freewheels bearing runs opposite to the first holding direction of the first freewheel bearing. The rear wheel hub has a first end cap and a second end cap, which are placed at the both ends of the hub axis and lie onto the front side ends of the hub axis at their inner side, so that a clamping force causing in axial direction to the rear wheel hub is transferable from the end caps over the axle body. The first and second hub bearings have two bearing units, where the hub body has first and second bearing receptions for the first and second hub bearings, where the bearing receptions are formed for receiving the two bearing units. One of the two bearing units is exchangeable against a distance unit per hub bearing. The first front wheeling is formed to a first disk body, which is floatably held in relation to the rotational axis and is edged by a pre-clamping device in direction to the second front wheeling. The second front wheeling is immovably held into a pre-clamping direction, where the second front wheeling is formed at a second disk body, which is screwed into a reception opening of the hub body. The screwing direction corresponds to the coupling direction. The pre-clamping direction has an elastic resetting device, which supports at the freewheel body and pushes the first disk body in direction to the second front wheeling. The elastic resetting device is formed itself, so that the first disk body is simultaneously pushed in direction to the second front wheeling and a pre-clamping force is producible against a tilting of the first disk body. The pre-clamping device has an elastic ring body, which is arranged between the freewheel body and the first disk body and lies onto the first disk body. The hub bearing, which is oriented towards the freewheel body, has an inner wheel ring and an outer wheel ring. The second front wheeling is formed in one piece with the outer wheel ring. The second front wheeling is formed at a second disk body, which is screwed into a reception opening of the hub body. An independent claim is included for an impeller for a bicycle.