Patent ID: 9180026
Filing Date: 2015-11-10
Classification: A61F,F16F

Abstract:
1. An adjustment-free cushioning air cylinder for use in a prosthesis joint, comprising: an air cylinder body, wherein an air chamber is formed in the inner of the air cylinder body; a piston, wherein one end of the piston is slidably disposed in the air chamber, and the other end extends to the external of the air cylinder body; the piston divides the air chamber into an upper air chamber and a lower air chamber, and does a reciprocating movement between a first position and a second position in the air chamber; a first non-return check valve, wherein the first check valve is disposed in the piston, one end of the first check valve is connected to the upper air chamber, and the other end is connected to the lower air chamber, so as to allow the air unidirectionally flowing from the upper air chamber to the lower air chamber; an upper air way, wherein the upper air way is formed within the air cylinder body and connects the upper air chamber with the outside; a second non-return check valve, wherein the second check valve is disposed in the upper air way, one end of the second check valve is connected to the outside, and the other end is connected to the upper air chamber so as to allow the air unidirectionally flowing from the outside to the upper air chamber; and a lower air way, wherein the lower air way is formed inside the air cylinder body and connects lower air chamber with the outside; and a third non-return check valve which is disposed in the lower air way to allow the air unidirectionally flowing from the lower air chamber to the outside; wherein a bore diameter of the upper air way is larger than that of the lower air way so that the entering flow rate of the air chamber is larger than the discharging flow rate.