Page 38 - PNEUMATIC AND HYDRAULIC

2.7 Actuator

2.7.1 Double Acting Cylinder

This is a standard cylinder that produces reciprocating motion. It is available in single

and double rod types. Figure 2.7 shows the single rod cylinder. This cylinder is

provided with a cushion mechanism, which uses a cushion sleeve to close the fluid
return port as the piston rod retracts. Therefore, the fluid is discharged through a

restrictor located in parallel with the return port, resulting in a higher piston back
pressure and a slower piston speed.

Figure 2.7: Double Acting Cylinder

2.7.2 Single Acting Cylinder

This is a cylinder that pushes the piston in one way (extending direction). The piston
rod is returned by gravitation or a mechanical force.

Figure 2.8: Single Acting Cylinder

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