| 摘要 |
PURPOSE:To generate a braking force with its size enlarged by steps by a method wherein a retarder consisting of a plurality of retarder units and a magnetic rotor is provided between an engine and speed change means and the exciting coils of the retarder units are selectively excited. CONSTITUTION:A rotor 5 constituted of a flywheel provided with a multiplicity of teeth 9 is provided between an engine and speed change means and,in their proximity, a plurality of retarder units 7 consisting of iron cores 13, exciting coils 10, and short-circuit rings 15 are arranged, to form a brake. The exciting coils 10 of the retarder units 7 are connected to a power source circuit via switches Sl-sn, so that the coils 10 are energized in order when the switches Sl-Sn are closed in order. Accordingly, the retarder braking force is controlled by steps by adjusting the number of switches to be closed, which enables the generation of a braking force with its size dependent upon the load size. |
