Abstract: An armrest adjusting device for adjusting armrest of chairs includes a hollow armrest seat and a guide plate is fixedly inserted into the armrest seat. A movable member is movably received in the armrest and includes a push end which includes tapered surfaces to control two rods to be removably engaged with click notches in the vertical portion of the elevator part which is connected to the seat of the chair. The vertical portion is inserted in the armrest seat. The movable member is operated via an opening defined through a wall of the armrest seat which is moved with the movable member. The armrest seat does not need to make large holes so as to increase the structural strength and the armrest adjusting device can also be used with tubular elevator part.

Abstract: A rail adjustment device including an adjustment mechanism for adjusting and locating the rail. The adjustment mechanism includes a bar body having a locating section. Multiple pairs of notches are formed on opposite corners of the locating section. By means of swiveling the bar body, a locating member can be engaged in or disengaged from one of the notches. The locating member can be snugly engaged in the notch without swinging. This ensures good quality of the rail in use or operation.

Abstract: A chair arm includes an inner post having a first end secured on a chair and a second opposite to the first end of the inner post. The inner post includes a first slot longitudinally defined therein near the second end of the inner post and extending through the inner post. The first slot has two opposite sides each having a series of first indentations defined in the inner post. An outer post is sleeved on the inner post. The outer post has a through hole defined therein and communicating with the first slot when the outer post partially receiving the inner post. A locking device is reciprocally slidably mounted in the through hole and extending into the inner post to selectively hold the outer post in place.