| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an actuator capable of stably regulating retraction of a piston rod after operation, and easily coping with a change of bending rigidity of the piston rod supporting a stopper. <P>SOLUTION: This actuator 21 supports the stopper for receiving an object to be protected by advancing the piston rod 50 in a cylinder 22 during operation. A lock mechanism R for regulating retraction of the piston rod includes a locking ring 71 to be housed in a housing groove 53 of a piston part 51, and a locking stepped part 26 on the cylinder side. The locking stepped part includes a locking regulation surface 27 and an outer circumference regulation surface 28. A tapered regulation surface 58 at the housing groove of the piston part abuts on an inner side surface 75 on the advance side of the locking ring 71 under a condition where the diameter of the tapered regulation surface 58 at the housing groove of the piston part increases after advance of the piston rod and under such a condition as to abut on the locking regulation surface of the locking stepped part and the outer circumference regulation surface and retraction of the piston rod 50 is regulated, using the locking ring 71 regulated by the locking stepped part. <P>COPYRIGHT: (C)2010,JPO&INPIT |
