| 摘要 |
<p>The present invention relates to a screw rotor machine which incorporates a sound silencing device in the vicinity of the inlet and/or outlet port. In accordance with the invention, the sound silencing device comprises a Laval-nozzle (8) having a valve body (9) which is movable axially in relation to the nozzle. When the machine is shut-down, the valve body (9) lies sealingly against the opening (8A) of the nozzle. When increasing the capacity of the machine to full load, the valve body (9) moves in the opening direction under the influence of a damping force and against the action of a substantially constant spring force (14), so as to maintain a flow rate immediately beneath the sound speed in the smallest area (8A) of the nozzle (8).</p> |
