PURPOSE: To reduce the number of operation times of a brake to a half of that of a conventional art and to provide an increased life for a brake mechanism part by always opening a brake during energization to either an electric motor for a high speed or an electric motor for a low speed.
CONSTITUTION: A circuit wherein during energization to either an electric motor MOS for a high speed or an electric motor MOC for a low speed, a brake BR is always brought into an opening state is constituted. For example, by pressing the first stage of a two-stage push type push button switch PB, an inverter INV is started, and the electric motor MOC for a low speed is energized. Since, during operation of the inverter INV, a signal is always outputted from an RUN terminal, through utilization of the signal, the brake BR is always brought into an opening state. Since, during high speed operation, the inverter INV is also under operation, the brake BR is left released. This constitution reduces the number of operation times of the brake BR to a half, whereby an increased life can be provided for a brake mechanism.
JPH08199802 | LIFELINE WINDING EQUIPMENT OF GONDOLA EQUIPMENT |
WO/2014/053299 | DRUM HOIST WITH A DRIVEN MAIN SHAFT |
SAITO KAZUMASA
SHIMODAIRA TOYOHISA