| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a double locking device that achieves easy workability during extension/contraction adjustment and sure fixing performance in a pipe structure. <P>SOLUTION: The double locking device 10 in a pipe structure includes a stepped locking mechanism and a non-stepped locking mechanism 50. The stepped locking mechanism is configured as follows. In a spring-coil clearance, a spring coil 35 is engaged with the outer-peripheral surface of an external pipe 20 while being sandwiched between a locking step 24 and an intermediate wall. In a locking-protrusion clearance, when a locking protrusion 22 is in a small-diameter clearance area, the locking protrusion is fitted to a locking groove 41 via a fitting insertion hole 23, and also, when the locking protrusion 22 is in a large-diameter clearance area, the locking protrusion is disengaged from the locking groove 41 via the fitting insertion hole 23. The non-stepped locking mechanism 50 is configured such that a pressing screw 43 formed at the tip of an inner pipe 40 is screwed into a tapered hole 52 of an expansion piece 51, brought into sliding contact with the external pipe 20, to allow the tapered hole 52 to expand or contract. <P>COPYRIGHT: (C)2012,JPO&INPIT |
