Patent ID: 7074013

Claim:
A scroll machine comprising: a first scroll member having a first spiral wrap projecting outwardly from a first end plate; a second scroll member having a second spiral wrap projecting outwardly from a second end plate, said second spiral wrap being interleaved with said first spiral wrap; a drive member for causing said spiral wraps to orbit with respect to one another whereby said spiral wraps create pockets of progressively changing volume between a suction pressure zone at a suction pressure and a discharge pressure zone at a discharge pressure; a discharge passage placing one of said pockets in fluid communication with said discharge pressure zone; a plate member having first and second contact portions disposed adjacent said first scroll member, said entire first scroll member other than said discharge passage being covered by said plate member, said discharge passage extending through said plate member and said first end plate; a first annular seal disposed between said first contact portion of said plate member and said first end plate and surrounding said discharge passage; a second annular seal disposed between said second contact portion of said plate member and said first end plate and surrounding said first annular seal, thereby defining a chamber between said annular seals; and a passage for placing compressed fluid at a pressure intermediate said suction pressure and said discharge pressure in fluid communication with said chamber to pressure bias said first scroll member toward said second scroll member; wherein one of said first and second annular seals is an L-shaped seal.