| 摘要 |
605,533. Air compressors. WILDE, G. L., and ALLEN, F. J. Dec. 28, 1945, No. 35112. Drawings to Specification. [Class 110 (i)] Surging is prevented in a two-stage centrifugal compressor by reducing the area of the diffuser passages in one stage only. When the compressor is used as a supercharger for an internal-combustion reciprocating engine, the reduction takes place in the low-pressure stage and when used as the air-compressor in a gas turbine plant, the reduction takes place in the high-pressure stage. The reduction may be effected by diffuser vanes pivoted at their midpoints or at their leading edges,' or by plates pivoted in recesses in the diffuser blades or by diffuser blades slidingly mounted in grooves in the side walls. The moving vanes or plates are connected by mechanism so that all move together. The reduction may also be effected by a lateral movement of one diffuser side wall. The moving parts are operated by a servomotor through a spring-loaded toggle so that they move from one extreme position to the other. The servomotor may be responsive to the speed or the pressure-ratio of the compressor. When the compressor is driven through a variablespeed gear, the control is rendered ineffective when the low and medium speed gears are in use. |
