| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a screw fastening device 10, along with a screw loosening determination method, improving a rate of correct determination in determination of screw loosening, without causing increase in work load and operation time. <P>SOLUTION: A bit position measuring section 29 measures a position of a bit 27 as a relative position in relation to a placement surface 67 of a screw supplying device 13 when a screw 14 is acquired from the screw supplying device 13. The bit position measuring section also measures the position of the bit as a relative position in relation to a workpiece surface 74 where a screw 14 hole is provided when fastening of the screw 14 onto a workpiece 15 has been completed. A screw loosening determination section 57 determines that screw loosening has not occurred when, based on the first and second bit positions, a difference between the first and second bit positions falls within an allowable range. The screw loosening determination section determines that screw loosening has occurred when the difference between the first and second bit positions does not fall within the allowable range. <P>COPYRIGHT: (C)2013,JPO&INPIT |
