| 摘要 |
<p>1,005,663. Axial-flow compressors. GARRETT CORPORATION. Nov. 24, 1961 [Nov. 25, 1960], No. 42202/61. Heading F1C. [Also in Division G3] Control mechanism for a compressor comprises a vent valve which is actuated in accordance with the speed of the compressor such that the vent is open over a certain speed range but is closed at a predetermined speed. The control mechanism comprises a housing fed with air tapped from the compressor through a pipe 34 which passes through a filter and orifice member 66 to a chamber 65. The air flows through a nozzle 68 and passes to exhaust through an outlet 75. The flow through the nozzle is controlled by a valve member 77 slidable in a shaft 81 which rotates at a speed proportional to the compressor. The shaft carries weights 95 on spring arms 91, 93, the arm 93 being connected to a sleeve 84 axially slidable in the shaft. Movement of the sleeve is restricted by a pin 84 movable in a slot 83. When the speed increases above a predetermined value the pin moves in the slot and thus moves the spindle of valve 77 to restrict flow through the nozzle 68. The consequential rise in pressure in chamber 65 moves a piston 55 against a spring loading 61 to move a valve 40 from its seat 38 to a seat 43. This movement of the valve 40 permits flow from pipe 34 to a pipe 24 which leads to an actuating device, such as a diaphragm, of the vent valve to close this valve. When the speed is below the predetermined value the valve 40 is in the position shown and the pipe 24 is connected to atmosphere through outlet 48 to allow the vent valve to be open. The nozzle 68 is axially adjustable by ring 71 and is positioned such that the valve 72 does not seat on the nozzle when moved towards it thus avoiding wear.</p> |
