| 摘要 |
An impact cushioning and shock absorbing device disposed in the coupling between the actuating member of a press ram and the ram. The device is in the form of a hydraulic piston-cylinder assembly defining a chamber which is filled with an uncompressible hydraulic fluid. The hydraulic fluid is pressurized by a compressed compressible fluid, such as air, acting on a large area piston directly coupled to a small area piston disposed in a small diameter cylinder filled with the incompressible hydraulic fluid and in communication with the chamber, the ratio in the areas of the pistons determining the pressure amplification rate or gain. When the press ram meets a resistance to its travel which is large enough to overcome the pressure of the hydraulic fluid in the chamber, the volume of the chamber is decreased with the result that hydraulic fluid is introduced in the small diameter cylinder, thus displacing the small area and the large area pistons against the pressure of the compressible fluid, and cushioning the impacts and shocks to which the ram is subjected in operation.
|
