MAIN SHAFT HOME POSITION STOP CONTROL CIRCUIT

摘要

PURPOSE:To stop main shaft in a home position by a method wherein after changing a main shaft motor control system to the home position stop control mode the main shaft motor is made to rotate at a constant speed of revolution slower by one constant revolving angle and afterwards being made to decelerate at a constant ratio. CONSTITUTION:At the stop control time of main shaft motor 3 the main shaft motor 3 lowers its speed of revolution by lowering a speed instruction signal VCMD from a speed instruction signal ORCM is given to the main shaft orientation control circuit 7 to turn a switch S1 OFF and to turn a switch S2 ON. The main motor 3 holds the constant speed of revolution by means of the speed control circuit 2 to which the speed instruction signal VCMD is given. When the porjection 61 goes by a sensor 62 a strobosignal STRB is given to give input to the control circuit 7 slowly lowering the speed instruction signal VCMD down to zero where the main shaft motor 3 stops.