FASTENING CONTROL SYSTEM OF SCREW

PROBLEM TO BE SOLVED: To properly control the fastening state of a screw based on a mode of a change of fastening torque acting on the screw. SOLUTION: This fastening control system 1 includes a torque wrench 2 with a torque release mechanism operated when reaching set torque, and a control device 3 controlling the fastening state of the screw by the torque wrench 2. The torque wrench 2 includes a strain gauge 13 detecting fastening torque information, a detection switch 15 detecting fastening completion information based on an operation of the torque release mechanism, and a transmission means 14 transmitting the fastening torque information and fastening completion information. The control device 3 includes a reception means 18 receiving the fastening torque information and fastening completion information, a peak detection means 19 successively detecting peak values in which the modes of the changes of the fastening torque information are changed from an increasing tendency to a decreasing tendency and outputting the peak value detected last when receiving the fastening completion information, a determination means 20 determining the propriety of the fastening state of the screw by the outputted peak value, and a portable information terminal 17 notifying the determination result. COPYRIGHT: (C)2010,JPO&INPIT