Abstract: The device avoids the use of screw-and-nut and facilitates the operations for mounting and dismantling the brakes. It comprises a support (10) for the brake (6) provided with tab (12) capable of engaging and resiliently clipping into a cavity (5) of the fork (3).

Abstract: A fork element 1 for guiding the chain is pivotally mounted by means of a deformable parallelogram structure 11, 12 on a support constituted by an arm 3 which is upwardly and outwardly inclined relative to a vertical plane containing the longitudinal axis of the bicycle. The parallelogram structure is deformed in a plane which is inclined in a direction parallel to said arm. With this arrangement, the fork element is shifted in a constant vertical position in a combined oblique upward and advancing movement so as to shift the chain from a small chain wheel to a larger chain wheel.

Abstract: The invention simplifies the manufacture of levers employed in particular for actuating cycle derailleurs and facilitates the mounting of the cable on these levers. For this purpose, the lever 20 has at least one cavity 31 in which the cable can be engaged resiliently in opposition to the action of a retaining device.

Abstract: The unit comprises a collar defining a bearing surface (13) for the lever, a fixing device such as a rivet (24) which also constitutes the journal on which the lever (25) is mounted, and an elastically yieldable washer (23). The collar defines also a cavity (16) for a member constituting an abutment for a cable sheath and may be provided with a rapid fixing device.

Abstract: The derailleur comprises, between the conventional articulation mechanism which allows the lateral displacement of the chain guide device (12), an additional articulation mechanism (10, 11) whereby the chain guide device (12) can effect a displacement which is substantially free and of large extent in a plane perpendicular to the axis (X--X) of the crank-gear. This very substantially improves the conditions under which the chain is shifted from one chain wheel to another.

Abstract: The derailleur comprises a chain guiding and shifting device in the form of a fork member (2) articulated to a support (1) adapted to be fixed to the frame of the bicycle. At least one (4) of the wings of the fork member (2) has a part (11) which is adjustable in position so as to adapt the width of the at least one wing (4) to the diameter of the small chain wheel of the crank-gear.

Abstract: The derailleur is shown in a retracted position allowing the dismantling of the rear wheel of the cycle. In this retracted position, it is maintained by an abutment which is rigid with the fixed part of the derailleur and is resiliently retained in a cavity defined by the concavity of a resiliently yieldable strip carried by a member fixed to the frame lug. In the operative position, the abutment is applied against the support surface of the lug.

Abstract: The invention provides a mechanism which is simpler in construction, cheaper and easier to assemble. The derailleur mechanism is of the type comprising a movable device for guiding or shifting the chain connected to a support in such manner as to be displaced in translation with respect to the support by means of an actuating device. The movable device is connected to the support, on one hand, by a link and, on the other hand, by a pin-and-slot connection. The slot has the shape of an arc of a circle whose radius is equal to the distance between the two pivot pins of the link.

Abstract: The object of the invention is to provide a mechanism whose construction and assembly are simplified and whose cost is consequently reduced. The mechanism comprises a support device, a movable device connected to the support device in such manner as to be movable in translation relative to the support device by an actuating device. The support device and movable device are mounted on an intermediate member to pivot about respective pivot pins. The two pivot pins are parallel to each other and the intermediate member defines two cavities which are parallel and extend in a direction orthogonal to the two pivot pins. Two push-members are slidably mounted in the two cavities and the ends of the push-members are respectively in contact with two parallel surfaces. One of the surfaces is defined on the movable device and the other is defined on the fixed device.