Patent ID: 6880675
Filing Date: 2005-04-19
Classification: E06C

Abstract:
1. A ladder assembly, comprising two symmetric support stands pivotally connected with each other, wherein: each of the two support stands includes a main frame, an upper frame, and a lower frame; the main frame of each of the two support stands includes two main uprights each having an inner side face having an upper end formed with a plurality of positioning holes; the upper frame of each of the two support stands is mounted on an upper portion of the main frame and includes two upper uprights each adjustably mounted on an upper portion of a respective one of the two main uprights of the main frame; the lower frame of each of the two support stands is mounted on a lower portion of the main frame and includes two lower uprights each adjustably mounted on a lower portion of a respective one of the two main uprights of the main frame; each of the two support stands further includes a retraction control unit including a support seat, two linking members, a press button, two operation rods, and two control seats, wherein: the support seat is formed with an operation slot; each of the two linking members is pivotally mounted on the support seat; the press button is slidably mounted in the operation slot of the support seat and has two ends each rested on a first end of a respective one of the two linking members; each of the two operation rods is slidably mounted in a respective one of the two upper uprights of the upper frame and has an upper end pivotally mounted on a second end of a respective one of the two linking members; and each of the two control seats includes a hollow body formed with a through hole, a locking member slidably mounted in the hollow body and provided with a locking stub extended through the through hole and detachably locked in one of the positioning holes of a respective one of the two main uprights of the main frame.