摘要 |
A cushion hydraulic cylinder is provided with a series of longitudinally separated metering orifices in the wall of the cylinder through which exhausted fluid is expelled. As the piston extends towards these metering orifices a seal sequentially cover and uncovers the metering orifices further restricting the flow of exhausted fluid. In addition the piston is provided with radial bores having one or more longitudinal passages which are in fluid communication with either the piston side of the cylinder or the rod side of the cylinder. The first longitudinal passage is provided with a passage orifice through which exhausted fluid can flow after a circumferential piston seal reopens a previously blocked metering orifice. The second longitudinal passage maybe provided with a check valve which prevents the flow of fluid in one direction.
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