Air-oil actuator type HPW

The air-oil actuator type HPW is used as a linking element in hydropneumatic actuators between the compressed air and the hydraulic system. Such open-circuit hydropneumatic systems normally comprise – viewed in the direction of energy transfer – the air-oil actuator, the flow control valve (or control block comprising several such valves) and the actuating cylinder. The energy of the compressed air is transferred from the upstream pneumatic circuit to the hydraulic system. Modern electrical signal processing systems determine on the one hand the sequences in the pneumatic section with simple EP-converters. The qualitative motion sequence in the hydraulic system can also be influenced by the fact that EP-converters and the previously described pneumatically adjustable hydropneumatic flow control valves can be used to apply signals to the hydraulic flow. Hydraulic flows in such hydropneumatic systems are very suitable for solving a number of actuation problems. The compressed air energy is quickly available due to the high flow speeds and is transferred to the hydraulic section with very little loss due to the use of the very latest technology. The hydraulic flow is free from periodical spurious oscillation, and when used in conjunction with the previously described air-oil actuator, is also free from non-periodical spurious oscillation. This very disturbing type of oscillation is often caused by trapped, non-dissolved air and unsuitable seal combinations combined with a degreased hydraulic pressure medium.