Electromechanical unit to operate speedometer and odometer - has shaft operating speedometer, and secondary shaft operating odometer

摘要

The device is mounted in motor vehicles, and has a shaft rotating at a speed proportional instantaneous speed if the vehicle magnet is rotatably mounted on the shaft. An electromagnetic convertor is stationary w.r.t. the magnet and opposite to it. A first electronic circuit processes pulses from the convertor and applies a current proportional to the pulse frequency to an electromagnetic display unit whose deflection shows the vehicle instantaneous speed. A secondary shaft (9) is connected to the main shaft (1) through a stepping down gear transmission (2, 7, 8). A second permanent magnet (10) is connected to the secondary shaft (9) and rotates with it. A second electromagnetic convertor (11) is stationary w.r.t. the second magnet (10). A second electronic circuit (12) processes second convertor (11) pulses. It retransmits processed pulses to an electromagnet (13) operating a ratchet (14), in turn operating the odometer (16).