| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic screw fastener for determining screw floatation on the basis of a surface height of a work.SOLUTION: An automatic screw fastener comprises reciprocatably moving means 20 for freely moving a screw fastening tool unit 10 in the screwing-in direction of a screw N for rotatingly driving a bit 1 engageable with the screw N in predetermined torque and capable of also outputting position information of the bit 1, and a control device 30 for controlling the reciprocatably moving means 20 in driving, and the screw fastening tool unit 10 comprises a screw guide 3 freely slidable by including the bit 1, a screw guide spring 4 for always energizing the screw guide 3 to the tip side of the bit 1 and a photoelectronic sensor 40 in which the bit 1 outputs a bit relative movement signal by detecting the relative movement to the screw guide 3. The control device 30 also comprises a storage part for storing upper-lower limit ranges with every screw fastening point by determining screw floatation by comparing the upper-lower limit ranges of presetting a difference of a movement position of the bit 1 when completing screw fastening and when receiving the bit relative movement signal.SELECTED DRAWING: Figure 2 |
