| 摘要 |
A collapsible telescopic ladder is composed of several rungs, several ladder frame tubes 4, 7, 9 and bottom covers 5. The bottom covers are mounted at the lower end of the ladder frame tubes. There is a latch on every rung and is composed of a spring-loaded locking pin 2. There is a locking pin hole in every ladder frame tube which matches with the locking pin. The projecting end of the locking pin is spherical. A taper on every bottom cover engages the sphere of the locking pin to push it out of supporting engagement with the adjacent ladder frame tube. A button 1 may be provided on the locking pin. |
