×

Shaft seals for a screw compressor

  • US 3,975,123 A
  • Filed: 08/19/1974
  • Issued: 08/17/1976
  • Est. Priority Date: 09/03/1973
  • Status: Expired due to Term
First Claim
Patent Images

1. In a screw compressor comprising a housing (10) defining a working space (18) containing a pair of intermeshing male and female screw rotors, the screw rotors being mounted in said housing (10) by means of respective rotor shaft means, said housing (10) further defining respective bearing chambers which are supplied with lubricant and into which said respective rotor shaft means extend;

  • an inlet channel (20);

    an outlet channel (22); and

    port means in said housing communicating each of said inlet and outlet channels with the working space (18) of the housing, the improvement comprising;

    at least one shaft seal system associated with at least one of said rotor shaft means, each shaft seal system including;

    a pressure gas source means including at least a first pressure gas source (28), and means including port means in said working space for communicating said first pressure gas source with the high pressure side of the working space; and

    four spaced seal sections (58,56,54,52) mounted with a positive clearance relative to an associated rotor shaft means;

    an annular intermediate pressure chamber (64) being defined between the first (58) and second (56) seal sections, an annular blocking pressure chamber (62) being defined between the second (56) and third (54) seal sections and being in communication with said first pressure gas source (28), and a drain space (60) defined between the third (54) and the fourth (52) seal sections;

    said first seal section (58) being disposed between the working space (18) of the compressor and the intermediate pressure chamber (64), the second seal section (56) being disposed between the intermediate pressure chamber (64) and the blocking pressure chamber (62), the third seal section (54) being disposed between the blocking pressure chamber (62) and the drainage space (60), and the fourth seal section (52) being disposed between the drainage space (60) and the bearing chamber (36,40) of the related shaft means; and

    means for communicating said first pressure gas source (28) with said blocking chamber (62);

    said drain space draining away any lubricant from the bearing chamber passing over the fourth seal section and any gas passing over the third seal section.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×