Scroll machine

Abstract

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 said 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. 
     
     
       12. 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 plate;   a second scroll member having a second spiral wrap projecting outwardly from a second end plate, 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 assembly disposed between said discharge pressure zone and said discharge chamber, the complete assembly movable relative to said first scroll member and including a valve plate movable between a first open state and a closed state.   
     
     
       13. The scroll machine according to claim 12, wherein said discharge valve assembly moves axially with respect to said first scroll member. 
     
     
       14. The scroll machine according to claim 12, wherein said valve plate is normally in said first open state. 
     
     
       15. The scroll machine according to claim 12, wherein said discharge valve assembly is disposed within a recess formed by said first scroll member. 
     
     
       16. The scroll machine according to claim 12, wherein said discharge valve assembly further comprises a valve seat and a valve stop. 
     
     
       17. The scroll machine according to claim 16, wherein said valve plate moves with respect to said valve seat and said valve stop between said first open state and said closed state. 
     
     
       18. The scroll machine according to claim 16, wherein said valve plate engages said valve seat when said valve plate is in said closed state. 
     
     
       19. The scroll machine according to claim 16, wherein said valve plate is movable into a second open state. 
     
     
       20. The scroll machine according to claim 19, wherein said valve plate abuts said valve stop in said second open state. 
     
     
       21. The scroll machine according to claim 12, further comprising a biasing member applying a force on said discharge valve assembly to bias said discharge valve assembly in a first direction relative to said first scroll member. 
     
     
       22. The scroll machine according to claim 21, wherein said discharge valve assembly is movable in a second direction opposite to said first direction and against said force of said biasing member. 
     
     
       23. The scroll machine according to claim 12, wherein said discharge valve assembly is biased into engagement with said first scroll member. 
     
     
       24. The scroll machine according to claim 12, wherein said discharge valve assembly is movable between a first position and a second position relative to said first scroll member, said valve plate permitting communication between said discharge pressure zone and said discharge chamber when said discharge valve assembly is in either said first position or said second position and restricting communication between said discharge pressure zone and said discharge chamber when said valve plate is in said closed state and said discharge valve assembly is in said second position. 
     
     
       25. The scroll machine according to claim 24, wherein said discharge valve assembly abuts a surface of said first scroll member in said second position. 
     
     
       26. The scroll machine according to claim 24, further comprising a biasing member biasing said discharge valve assembly into said second position. 
     
     
       27. The scroll machine according to claim 24, wherein said discharge valve assembly is biased into said second position. 
     
     
       28. The scroll machine according to claim 12, wherein said discharge valve assembly and said valve plate cooperate to define a first open state, a second open state, a third open state, and a closed state. 
     
     
       29. The scroll machine according to claim 28, wherein said first open state, second open state, and said third open state provide three different flow levels between said discharge pressure zone and said discharge chamber and said closed state restricts flow between said discharge pressure zone and said discharge chamber. 
     
     
       30. The scroll machine according to claim 21, wherein said biasing member is a wave-ring. 
     
     
       31. The scroll machine according to claim 21, wherein said biasing member is received within a groove of said first scroll member. 
     
     
       32. The scroll machine according to claim 31, wherein said groove is an annular groove formed in a wall of said first scroll member. 
     
     
       33. The scroll machine according to claim 12, wherein movement of said valve plate between said first open state and said closed state is independent of movement of said discharge valve assembly relative to said first scroll member.