| 摘要 |
<p>PCT No. PCT/NL92/00076 Sec. 371 Date Nov. 10, 1993 Sec. 102(e) Date Nov. 10, 1993 PCT Filed Apr. 16, 1992 PCT Pub. No. WO92/18395 PCT Pub. Date Oct. 29, 1992.An assembly for closing a pipe mouth comprising a mouthpiece connected to a pipe mouth, and a stopper having an axially projecting portion which is adapted for insertion into the mouthpiece. The stopper includes a lock which is operable by a key, and such that in the released position, the stopper can be moved into and out of the mouthpiece with the key securely connected to the lock, and in the locked position the stopper is retained in the mouthpiece and the key may be removed. The lock includes a magnetic control means which permits the lock to be moveable between the released and locked positions only when the stopper is inserted in the mouthpiece.</p> |
