A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
A telescopic ladder including two columns, and a plurality of steps, each of which being formed by socketing a smaller tube in a bigger tube, each step being arranged between upper ends of two tubes of a same diameter; an instep-operable folding switch including an operating lever is provided below a first step on the bottom of the ladder; each end of the operating lever contacts a lower end of one transmission bar, an upper end of the transmission bar contacts an end of a pin switch for a second step, and the other end of the pin switch is hinged to a middle portion of a pin with its front end of the pin being fitted in positioning holes of two columns corresponding to the second step, and its rear end of the pin being resisted against a return spring located within a pin connector in the second step.
A telescopic ladder including two columns, and a plurality of steps, each of which being formed by socketing a smaller tube in a bigger tube, each step being arranged between upper ends of two tubes of a same diameter; an instep-operable folding switch including an operating lever is provided below a first step on the bottom of the ladder; each end of the operating lever contacts a lower end of one transmission bar, an upper end of the transmission bar contacts an end of a pin switch for a second step, and the other end of the pin switch is hinged to a middle portion of a pin with its front end of the pin being fitted in positioning holes of two columns corresponding to the second step, and its rear end of the pin being resisted against a return spring located within a pin connector in the second step.
Telescopic Ladder
PAN YUEJIN (author)
2021-09-02
Patent
Electronic Resource
English
IPC:
E06C
LADDERS
,
Leitern