BOLT FASTENING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a bolt fastening device capable of changing over the fastening tool quickly and easily in accordance with the sort of the bolt to be tightened. SOLUTION: The bolt fastening device to tighten a bolt by turning a nut runner 3 is composed of a socket 21 for hexagonal bolt which is equipped at the tip with a socket part 23 to admit fitting-in of the head of a hexagonal bolt and whose base end is coupled with the output shaft 3a of the nut runner 3, a wrench 26 for a bolt with fit hole located in extension coaxially with the socket 21 to be turned in a single piece and having a wrench part 27 to be fitted in the fit hole of the bolt, and a tool changeover means 41 allowing the wrench 26 and socket 21 to make relative movement in the axial direction and moving the wrench part 27 between the protrusive position protruding from the socket part 23 and the retracted position to make retraction into the socket part 23.