Improved non-return valve device for fluids

摘要

This non-return valve has a retention spring 2 placed outside the body 1 of the valve. This spring is held on the body of the valve by screwing its rear turns into a threading 5 cut into the outer surface of the body of the valve; it embraces the stopper disc 3 and retains the latter by means of a closure turn 6 of smaller diameter. This spring has a large diameter and it can therefore be manufactured from less expensive materials than if it had to be mounted inside the body of the valve. Furthermore, it correctly guides the stopper element in its opening and closing movements. <IMAGE>