JPS6411740A - Screw tightening device - Google Patents

Abstract

PURPOSE:To reduce screws, improperly tightened, by providing a controller, which performs an instruction of action to a screw tightening mechanism, and means, generating an instruction signal of performing temporary tightening by a high speed and low torque and an instruction signal of performing the final tightening by a low speed and high torque, in the controller. CONSTITUTION:A screw tightening device 1 provides a screw tightening mechanism 2, in which a screw 10 supplied from a screw supplying mechanism 3 is tightened to an assigned part P, and a controller 8 which performs an instruction of screwing and tightening action. The controller 8, which provides a temporary tightening instruction signal generating means 8a performing temporary tightening by a relatively high speed further low torque, performs the temporary tightening being based on this temporary tightening instruction signal A. While providing also a final tightening instruction signal generating means 8b performing final tightening by a relatively low speed further high torque, the final tightening is performed by the screw tightening mechanism 2 by generating a final tightening instruction signal B after the temporary tightening is completed. Accordingly, the reduction of improper screw tightening and the orientation to high speed tightening can be attained.