Patent ID: 6213731
Filing Date: 2001-04-10
Classification: F01C,F04C,F25B

Abstract:
A scroll-type machine comprising:a first scroll member having a first end plate and a first spiral wrap extending therefrom;a second scroll member having a second end plate and a second spiral wrap extending therefrom, said first and second scroll members being positioned with said first and second spiral wraps interleaved with each other;a drive member for causing said scroll members to orbit relative to one another whereby said spiral wraps will create pockets of progressively changing volume between a suction pressure zone and a discharge pressure zone;said first and second scroll members being movable between a first relationship in which sealing surfaces of said first and second scroll members are in sealing relationship to close off said pockets and a second relationship wherein at least one of said sealing surfaces of said first and second scroll members are spaced apart to define a leakage path between said pockets; anda fluid operated piston secured to said first scroll, said piston being actuatable to apply a force to said first scroll to move said first scroll between said first relationship where said scroll machine operates at substantially full capacity and said second relationship in which said scroll machine operates at substantially zero capacity.