Abstract: A tensioning device for a power-transmitting drive, which can be blocked by a safety element is provided. The safety element (5, 11, 15, 18) can be deactivated automatically through the installation of the tensioning device (1) on a motor or through the installation of another component.

Abstract: A gear selection device for a variable gear mechanism, especially for a bicycle gear drive mechanism, with a control device, which acts via a force-transmitting element on the variable gear mechanism; with an actuating device with a rotatable actuating element for manual actuation of the control device; and with a display device with an indicator element, which can move along an arc to display the engaged gear selected via the actuating device. The angular movement of the actuating device or control device is transmitted via a transmission device to the display device in such a way that the arc through which the indicator element of the display device passes is smaller than the arc through which the actuating element of the actuating device passes as the same time. This improves the readability of the display device and also improves the ergonomics of the gear selection device.

Abstract: A one-way transmission with a resetting function for use in ratchet mechanisms. The resetting spring for the actuating lever is arranged to also takes over the prestressing of the one-way transmission element. The integration of the following switch components is also possible; the shift lever and the one-way transmission element; the shift lever, the one-way transmission element and the resetting spring; the positioning device and the positioning pawls; of the positioning device and actuating button; the actuating button and the resetting element; and the positioning device, the actuating button and the resetting element.

Abstract: A shift mechanism for a bicycle gear assembly that includes an actuating part that may be moved by an actuating lever or a release lever to shift between the gears of the gear assembly. The actuating and release levers operate independently from each other. The actuating part has a winding groove for receiving a cable connected to the gear assembly and first and second toothed segments. The release lever controls a detent element having first and second detent noses that are alternately engageable with the first and second toothed segments, respectively. The release lever may also have a cam contour that allows at least two gears to be shifted upon actuation of the release lever.

Abstract: A gear selection device for a variable gear mechanism, especially for a bicycle gear drive mechanism, with a control device, which acts via a force-transmitting element on the variable gear mechanism; with an actuating device with a rotatable actuating element for manual actuation of the control device; and with a display device with an indicator element, which can move along an arc to display the engaged gear selected via the actuating device. The angular movement of the actuating device or control device is transmitted via a transmission device to the display device in such a way that the arc through which the indicator element of the display device passes is smaller than the arc through which the actuating element of the actuating device passes as the same time. This improves the readability of the display device and also improves the ergonomics of the gear selection device.

Abstract: A one-way transmission with a resetting function for use in ratchet mechanisms. The resetting spring for the actuating lever is arranged to also takes over the prestressing of the one-way transmission element. The integration of the following switch components is also possible; the shift lever and the one-way transmission element; the shift lever, the one-way transmission element and the resetting spring; the positioning device and the positioning pawls; of the positioning device and actuating button; the actuating button and the resetting element; and the positioning device, the actuating button and the resetting element.

Abstract: A gearshift for bicycle gears includes an operating lever arranged so as to be rotatable around a stationary central axis for controlling an operating part arranged in a housing. The operating part is also rotatable around the central axis and has a take-up groove for receiving a gear-shifting cable, whereby a latch interacts with a tooth mechanism on the operating part for winding the cable. The gearshift further includes a release-and-hold mechanism consisting of a first latching disk having a first latching segment and a second latching disk having a second latching segment connected to the operating part, and of a release lever that interacts alternately with the first latching segment and the second latching segment. Arranged on the release lever are a first latching lug and a second latching lug, which alternately engage with the first latching segment and the second latching segment.