| 摘要 |
PURPOSE:To reduce noise level in the audible frequency region of a rotary type compressor by covering both ends of a tubular portion having axial ribs projecting centripetally while interconnecting said both ends with a cup-like lid. CONSTITUTION:An enclosing case 23 is constituted from a stator 22 of a motor 5, a cylindrical portion 24 fixedly circumscribing a bearing 8 and cup-like covers 17, 18 fixed to both ends of said portion 24. The cylindrical portion 24 is formed with a plurality of axial ribs 24a interconnecting both ends of said portion 24 and projecting centripetally. By such constitution is increased the rigidity of the enclosing case 23 against the deformation of axial section, and the natural vibration mode shifts outside the audible frequency region so that the occurrence of noise of about 2kHz-5kHz easy to hear for a man can be reduced. |
