A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
SEALING SLEEVE AND TELESCOPIC LADDER
A closure cover and an extension ladder are provided, relating to the technical field of daily tools. The closure cover comprises an upper closure plate (100), a lower closure plate (200), and two airtight sheets (300), the upper closure plate (100) and the lower closure plate (200) are fixedly connected by a connector (800), the upper closure plate (100) and the lower closure plate (200) are each provided with ventilation holes (101), the airtight sheets are fixed to a surface of the upper closure plate (100) facing away from the lower closure plate (200) and a surface of the lower closure plate (200) facing away from the upper closure plate (100), respectively, and the airtight sheets (300) are capable of controlling the closing and opening of the ventilation holes (101). The disclosure alleviates the technical problem that the extension ladder in the prior art is likely to cause a pinching injury or a crush injury to the user due to an excessively fast descending speed during retraction.
SEALING SLEEVE AND TELESCOPIC LADDER
A closure cover and an extension ladder are provided, relating to the technical field of daily tools. The closure cover comprises an upper closure plate (100), a lower closure plate (200), and two airtight sheets (300), the upper closure plate (100) and the lower closure plate (200) are fixedly connected by a connector (800), the upper closure plate (100) and the lower closure plate (200) are each provided with ventilation holes (101), the airtight sheets are fixed to a surface of the upper closure plate (100) facing away from the lower closure plate (200) and a surface of the lower closure plate (200) facing away from the upper closure plate (100), respectively, and the airtight sheets (300) are capable of controlling the closing and opening of the ventilation holes (101). The disclosure alleviates the technical problem that the extension ladder in the prior art is likely to cause a pinching injury or a crush injury to the user due to an excessively fast descending speed during retraction.
SEALING SLEEVE AND TELESCOPIC LADDER
DICHTUNGSMUFFE UND AUSZIEHBARE LEITER
MANCHON D'ÉTANCHÉITÉ ET ÉCHELLE TÉLESCOPIQUE
ZHOU MINQING (author) / HUANG JINCHAI (author)
2021-01-20
Patent
Electronic Resource
English
IPC:
E06C
LADDERS
,
Leitern