Device in fluid-containing cylinders having a fluid-operated piston

Claim 1

A fluid-controlled buffer device in cylinders having a fluidoperated working piston, comprising a buffer piston concentrically mounted at one end of the working piston and having a substantially smaller diameter than the diameter of working piston, a bore communicating with a fluid outlet at one end of said cylinder, said buffer piston being adapted to enter and gradually throttle said bore communicating with said fluid outlet upon the working piston approaching said end of the cylinder, said buffer piston comprising a cylindrical body, said bore having a diameter larger than the diameter of the cylindrical body as to form an annular clearance between the peripheral surfaces of the body and the bore upon the cylindrical body being positioned within the bore, a flexible slotted sealing ring having a non-deformable cross-sectional area being mounted in an annular notch located in at least one of said peripheral surfaces and extending into said annular clearance, said notch having a diameter facilitating radial play between the sealing ring and the peripheral surface of the notch to provide for radial displacement of the cylindrical body, said sealing ring slidingly engaging the other of said peripheral surfaces, axial recesses in the peripheral surface slidingly engaging said sealing ring at the end adapted to be initially engaged by the sealing ring for effecting a pressure reduction on the sealing ring until the end portion of said peripheral surface enters the sealing ring, said peripheral surface further including passages adapted to, upon the cylindrical body being moved into the bore, initially permit the flow of fluid from the cylinder to the outlet opening, said passages being adapted to be successively closed by axial movement relative to the sealing ring to thereby gradually reduce the total effective area of the passages while concurrently maintaining a turbulent flow of the fluid through the passages.