Backrest elevator device

摘要

A backrest elevator device has a main plate, an adjustment panel, a driven block, a spring, and a cover plate. The main plate has a hollow interior, a corrugated slot, and a plurality of serrations. The adjustment panel has a chamber and a guide groove communicating with the chamber. The driven block has a protruded block. The driven block is inserted in the chamber. The spring is disposed between the adjustment panel and the driven block. The cover plate is disposed on the adjustment panel to cover the chamber. The adjustment panel engages with the main plate. The protruded block engages with two of the serrations.