Drive unit of pressure device

Abstract

A drive unit of a pressure device, such as a welding gun, includes a piezoelectric type load cell adapted to be arranged in an easily attached and removed manner and to have relatively small capacity. The drive unit includes a through-hole 6, formed in a rotary shaft 5 of a drive motor 1, which is a drive source, and a pressure shaft 10, configured to be able to move with a part thereof being in the through-hole 6. The rotary shaft 5 is rotatably supported by the bearing 7, and the piezoelectric type load cell 17 is sandwiched between a preload striker plate 18, through which the pressure shaft 10 passes, and a preload setting striker plate 19, through which the pressure shaft 10 passes with a preload exerted on the load cell 17.

Dependencies are inferred from the claim text.