Tapping device for reciprocative press

摘要

A device for simultaneously tapping threads and performing the usual operations of a punch press is described in which the tapping device is attached to the upper and lower plates of a punch press. As the punch plates are brought toward and away from each other, gear trains and helically grooved lead screws change the up and down motion into rotating motion. The gear trains also change the speed of the rotating motion which is used to drive a thread tapping tool through the metal being formed in the punch press. If there is too much force opposing the tapping operation, an electrical contact in the device is opened and the punch press stopped before the tap or tapping device can be damaged.