| 摘要 |
PURPOSE:To enhance the sealing ability of a seal ring, by providing such an arrangement that a back pressure is affected upon the seal ring by means of a back pressure means to make it possible to provide a seal by means of the contact surface pressure between the slidable contact surfac of the ring and the seal surface of a support member while oil is fed into between the seal surface and the slidable contact surface. CONSTITUTION:An annular chamber 9 is formed in either one of a revolving scroll 3 and a support member 8, and a seal surface 83 is provided on the other one, and a seal ring 10 having a slidable contact surface 101 cooperated with the seal surface 83 is held in the annular chamber 9 so that a pressure chamber 14 is defined by the seal ring 10 while lubrication oil is fed into between the seal surface 83 and the slidable contact surface 101. There are provided an oil feed means comprising a second oil passage 27 communicated with a pressure chamber 14 through a back pressure chamber and as well communicated with a first oil feed passage 16 formed in a drive shaft 6, for feeding oil to a lubrication part and a back pressure means for making the back pressure act upon the seal ring 10. With this arrangement, since the seal defining the high pressure chamber 14 is satisfactory and the ring 10 is not the one which allows elastic deformation, it is possible to select materials having a high friction resistance, such as, for example, metal, etc. Accordingly, it is possible to enhance the sealing ability and durability of the seal ring. |
