An elevating gear comprises a hollow cylinder body with one end sealed and the other end opened, an elevating lever which is arranged in the cylinder body and one end of which extends out the cylinder body, a stating ring arranged at the opening end of the cylinder body and an adjusting button arranged on the elevating lever. The elevating lever is provided with a rack rod, the cylinder body is internally provided with a tip chute which is fixedly connected with the adjusting button, the tip chute is internally provided with a moving pin with one end matched and connected with the rack rod and the other end matched and connected with the bevel of the tip chute, the elevating lever is provided with a septa, a locking spring is arranged between the adjusting button and the septa, and an elevating spring is arranged between the bottom surface inside the cylinder body and the septa; the cylinder body is internally provided with a bracket which is matched with the moving pin; the rack rod is an oblique rack rod; the bottom of the cylinder body is provided with a locating pin which is corresponding to the position of the spring; a buffer piece is arranged between the bottom of the stating ring and the oblique rack rod; another buffer piece is arranged between the bottom of the cylinder body and the oblique rack rod; the buffer piece is a rubber damping ring. The elevating gear of the utility model adopts a mechanical clipping structure, facilitates processing and has low cost and long service life.