DYNAMICS OF PNEUMATIC CYLINDER SYSTEMS

To drive a pneumatic cylinder, meter-out circuit is used in many cases, since time to move the piston is constanteven if the load is changed. That is, the meter-out restriction method realized velocity control. However thisprinciple of velocity control has not been explained sufficiently. The purpose of this study is to make clear thevelocity control mechanism. In order to clarify this mechanism, nondimensional equations and their responses are presented. Consequently six parameters governing the cylinder response are obtained. As a result, by drawing theblock diagram of cylinder system, it is found that the compliance of a cylinder makes the feed back loop in cylinder velocity and the flow characteristics of restriction in choking compensates the constant velocity for changing a loadforce.