Unbalanced machinery vibration isolation with a semi-active pneumatic suspension

The problem of unbalanced machinery isolation is tackled in this paper. The proposed solution incorporates an air suspension that can be adapted depending on the turning frequency. The system is built with three main parts: an air spring, a reservoir and a connecting pipe. A model of the suspension excited by the unbalanced rotor is also shown in this paper. The properties of the system make it possible to use a configuration of the suspension (one pipe size) over a bandwidth range and another configuration (another pipe size) over the remaining bandwidth range. This idea is implemented with solenoid controlled valves and the results show significant improvements with respect to completely passive configurations.