Patent ID: 8056679
Filing Date: 2011-11-15
Classification: E06C

Abstract:
1. A retractable ladder comprising: a plurality of telescoping rail sections each having left and right side rail members, each of said left and right side rail members having two opposite lateral sides, and two aligned locking holes provided respectively in said lateral sides; and at least one control device including a shaft disposed rotatably between said left and right side rail members of one of said rail sections, two locking units disposed respectively on two opposite ends of said shaft to lock movement of said one of said rail sections relative to an adjacent one of said rail sections, and an operating member fixed between said two opposite ends of said shaft to rotate said shaft, each of said locking units having a controlled piece fixed to and rotatable along with said shaft, two abutment plates abutting respectively against two opposite sides of said controlled piece, two locking pins extending outwardly and respectively from said abutment plates, and two spring members sleeved respectively on said locking pins and biasing said abutment plates to abut respectively against said two opposite sides of said controlled piece; said controlled piece being rotatable between a pushing position to push said locking pins to project outwardly and respectively from said locking holes in said one of said rail sections and engage respectively said locking holes in said adjacent one of said rail sections, and a non-pushing position, where said locking pins are permitted to extend inwardly so as to disengage from said locking holes in said adjacent one of said rail sections.