공압용 실린더의 릴리프 밸브와 니들밸브의 쿠션 특성에 관한 연구

A Study on the Cushion Characteristics Relief Valve and Needle Valve Type in Pneumatic Cylinder

Pneumatic cylinders are most widely used as actuators in automatic equipment because they are available in a wide of power and stroke, simple to install and operation. Due to the tendency to use high-speed driving pneumatic cylinders to improve productivity, they are required rapid acceleration and deceleration of the piston motion. This paper presents a study of the dynamic characteristics of cushion processes in relief and needle valve type cushion mechanism in meter-out speed control system. Of interest here is to investigate the effect of varying the piston velocities. The simulation results of pressure in the cushion chamber and the dynamic behaviors of the relief valve type cushion mechanism are compared with the needle valve type, which help to understand the performance and improve or design the better cushion configurations in pneumatic cushion cylinder. Based on the relation between absorbed energy and impact energy in cushion process, cushion performances are evaluated.