Tachogenerator device for acquiring rotation speed of wheel of bicycle, has magnet piece integrated in carrier part that is formed for fixation of magnet piece at valve, and sensor mountable at vehicle part in torque-proof manner

摘要

The device has a sensor (16) i.e. Hall sensor, mountable at a vehicle part in a torque-proof manner, where the vehicle part is disconnected from a wheel (20) of a vehicle i.e. bicycle (12). A magnet piece (24) is fixed at the vehicle part, where movement of the magnet piece at the sensor induces a signal for an electronic evaluation unit i.e. tachometer (10). The magnet piece is integrated in a carrier part (22) that is formed for fixation of the magnet piece at a valve (18) without modification of a valve stem. The carrier part is formed as a valve cap or as a functional part of the valve. The magnet piece is formed by a ring magnet. The vehicle part is selected from a group comprising a fork (14), a brake or a rear wheel guide.