Racine, WI —Engineers have long wanted a 3,000 psi vane pump, but the task of designing one has been difficult to achieve. Bosch Automation Technology has responded to these requests by designing a pressure compensated, variable volume vane pump known as the VPV Whisper Pump.
Key to the design is a pressure proportional regulator valve, which also addressed other design considerations, such as low noise levels and high-pressure capability. The greatest challenge involved reducing vane and pressure ring wear at high pressures.
The patented pressure proportioning regulator valve consists of a valve housing with a passage containing inlet, return, outlet ducts, and a valve gate. To maintain a constant pressure ratio, the valve gate contains a piston, and a sliding control member for reducing pressure.
Engineers were able to reduce the noise output by an average of 3 dB(A) per model for a decibel level from the upper 40's on the VPV 16 to the mid 70's for the VPV 164. Sound pressure levels were measured in an anechoic chamber with a microphone placed one meter away at various locations. The average sound pressure levels were spatially- and time-weighted.
Integration of components was also key to the success of lowering the decibel level. Direct mounting of the pump into the electric motor eliminates the need for a traditional coupling, reducing assembly time. The removal of the coupling also has the potential to reduce the vibratory influence present in bell housing/coupling installations, and the sound level of the unit overall.
Additional Details... Contact Karen Ford, 7505 Durand Ave., Racine, WI 53406; Tel: (262) 554-7100; FAX: (262) 554-7117; www.boschat.com ,
or Enter No. 581
.