Drive device for driving draft rollers in spinning machine

摘要

Spinning machine includes draft rollers 3, 4 and 5 and a drive device for driving the draft rollers. The drive device has a drive unit 6 for driving the front draft roller 5, and a drive unit 7 for driving the back and middle draft rollers 3 and 4. Each drive unit has a variable speed motor M2 or M3 and a transmission mechanism, and the variable speed motor of the drive unit 6 for driving the front draft roller 5 is a synchronous AC motor having permanent magnets. A reverse rotation preventing device including a ratchet wheel and a pawl is arranged in the drive unit 6 for preventing a reverse rotation of the front draft roller 5, occurring with a reverse rotation of the synchronous motor M2, caused by the action of the permanent magnets in the synchronous motor upon starting the synchronous motor. <IMAGE>