A compressor includes a normally open discharge valve assembly for controlling compressed refrigerant flow from the discharge chamber through the compression members. This controlling of flow results in an increased performance for the compressor by reducing recompression volume and the elimination of reverse rotation at shut down. The discharge valve assembly includes a valve seat, a valve plate and a valve stop secured within a recess formed within the compressor with a wave ring retainer. The valve stop and the valve seat include a contoured surface that is engaged by the valve plate when it opens and closes. The contoured surface controls the movement of the valve plate.
1. A scroll machine comprising:
a shell defining a discharge chamber;
a first scroll member having a first spiral wrap projecting outwardly from a first end cap;
a second scroll member having a second spiral wrap projecting outwardly from a second end cap, said second spiral wrap being intermeshed with said first spiral wrap;
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 discharge pressure zone being in communication with said discharge chamber; and
a discharge valve disposed between said discharge pressure zone and said discharge chamber, said discharge valve being disposed within a recess formed by said first scroll member, said discharge valve being movable between a first, a second, and a third position, wherein:
said first position is a closed position where said discharge valve abuts a bottom surface of said recess and fluid flow between said discharge chamber and said discharge pressure zone is prohibited;
said second position is an open position where said discharge valve abuts said bottom surface of said recess and fluid flow between said discharge chamber and said discharge chamber and said discharge pressure zone is permitted at a first flow level; and
said third position is an open position where said discharge valve is spaced from said bottom surface of said recess and fluid flow between said discharge chamber and said discharge pressure zone is permitted at a second flow level greater than said first flow level.
2. The scroll machine according to claim 1 , wherein said discharge valve moves axially with respect to said first scroll member.
3. The scroll machine according to claim 1 , wherein fluid flows around an outer periphery of said discharge valve when said discharge valve is in said third position.
4. The scroll machine according to claim 1 , wherein a passage between said first scroll member and said discharge valve is opened when discharge valve moves from said second position to said third position.
5. The scroll machine according to claim 1 , wherein said discharge valve comprises a valve plate and a valve stop.
6. The scroll machine according to claim 5 , wherein said valve plate moves with respect to said valve stop when discharge valve moves from said first position to said third position.
7. The scroll machine according to claim 5 , wherein said valve plate moves with respect to said first scroll member when said discharge valve moves from said second position to said third position.
8. The scroll machine according to claim 1 , wherein said discharge valve comprises a valve seat and a valve plate.
9. The scroll machine according to claim 8 , wherein said valve plate moves with respect to said valve seat when said discharge valve moves from said first position to said second position.
10. The scroll machine according to claim 8 , wherein said valve plate moves with respect to said first scroll member when said discharge valve moves from said second position to said third position.
11. The scroll machine according to claim 1 , wherein said discharge valve comprises a valve seat, a valve plate and a valve stop.