MOTOR CONTROL APPARATUS FOR A RAILWAY SWITCH MACHINE

摘要

A motor control apparatus (104) for a railway switch machine (106) includes a power source (134) for a voltage; a selector (132) for providing the voltage to a reversible motor (105) of the switch machine (106) in a normal state, a nd for providing a reverse polarity of the voltage to the reversible motor (105 ) in a reverse state; a first transistor (129) for switching reverse current flowing through the reversible motor (105); a first diode (131) electrically connected in parallel with the first transistor (129) for conducting normal current for the reversible motor (105); a second transistor (128) for switching normal current flowing through the reversible motor (105); a secon d diode (130) electrically connected in parallel with the second transistor (128) for conducting reverse current for the reversible motor (105); and a circuit (118) for controlling the first and second transistors based upon th e position or operating mode of the railway switch machine (106).