Machine tool spindle motor control system design

A spindle consists of a three-phase squirrel-cage asynchronous motor drag, lubricating oil pump by another three phase squirrel-cage asynchronous motor drag, adopt direct start, technology requirements; ( 1) The spindle must after lubricating oil pump start to start; ( 2) Spindle for positive operation, convenient for debugging, to positive and reverse point move; ( 3) Spindle stopped, allowed to lubricating oil pump stop; ; ( 4) With the necessary electric protection. Press SF1 make QA2 electric locking, the lubricating oil pump MA2 starts, to push SF2, can make the QA1 electric locking, spindle motor MA1 was started. Press SF3 can make QA1 electricity, namely the spindle motor MA1 positive point move; According to SF4 can make QA3 electricity, namely the spindle motor MA1 reverse point move. When the lubricating oil pump to a halt, must first make the spindle motor, first stop, namely QA1 normally open off, then press the SF6.