| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent rotation of a lock ring upon excessive pulling-out force acting thereon while having good workability and guaranteeing high earthquake resistant performance. <P>SOLUTION: The lock ring of the earthquake-resistant pipe joint structure in which spigot projections 9 are locked with the lock ring 20 in a recessed groove 6 of a pipe socket inner face includes: a lock ring base part 11 having a one-split circular shape and fitted in the recessed groove; projecting pieces 12 projecting in the base part width direction at prescribed intervals over the entire periphery of the base part; and a cover 23 having slits 24 therearound for covering each of the projecting pieces. With this lock ring, as the projecting pieces are bent by sliding of the projections to projecting piece inner tapered faces 20a and insertion of the projections are allowed, there is no need to increase the diameter inside the recessed groove of the lock ring. As the projecting pieces and the cover can be made long or thick to become close to the length in the width direction of the recessed groove as much as possible, even when excessive pulling-out force is acted, the projecting pieces are positively abutted on an inner wall of the recessed groove, rotation of the lock ring is effectively inhibited, and pulling out of the spigot is effectively inhibited. <P>COPYRIGHT: (C)2012,JPO&INPIT |
