| 摘要 |
<p>A housing (10) contains a resiliently mounted electric motor (32) and compressor (30), which draws air into the housing through inlets (23) via a tortuous passage (20) formed by sound absorbent baffles (22), and delivers the air externally of the housing through outlets (54, 56). The housing (10) is made in two halves, each comprising a rigid metal outer layer (14) and a thermally conductive, sound absorbing inner layer (16), e.g. of lead-filled rubber. Silencers (38, 40) are preferably fitted to the compressor, and may comprise air expansion chambers. In this way the production of noise is reduced and its escape from the housing is kept low, since the housing does not need any openings for the through flow of cooling air by convection.</p> |
