This paper describes the theoretical-experimental study of an auto-adjustable stroke end cushioning device utilized in hydraulic cylinders, focusing the characterization of the bush geometry effect on the cushioning achieved. A nonlinear model is presented which includes the physical phenomena that exert a significant influence on the performance of this hydraulic component, such as: friction, fluid compressibility and pressure energy loss in the cushioning section. The model is validated through the comparison between theoretical and experimental results, under different conditions of load, supply pressure and piston speed. From this point it is possible to obtain a model applicable for the design of stroke end cushioning devices in hydraulic cylinders. Consequent contributions related to proportional directional valves modeling are also presented.
Hydraulic cylinders; cushioning; proportional valves
