Scroll compressor with anti-reverse rotation clutch

Abstract

A low cost protective clutch member is positioned adjacent an end of the drive shaft in a scroll compressor. The device is a thin washer having a tab which is selectively driven against the housing stop when the compressor is driven in a forward direction, but is movable into a notch in the shaft when the shaft is driven in a reverse direction. The tab prevents rotation of the shaft when in the notch.

1 . A scroll compressor comprising: 
 a first scroll member having a base and a generally spiral wrap extending from the base;    a second scroll member having a base and a generally spiral wrap extending from its base, said spiral wraps of said first and second scroll members interfitting to define compression chambers;    a drive shaft for causing said second scroll member to orbit relative to said first scroll member, said drive shaft being normally driven in a first direction; and    a device for allowing rotation of said drive shaft when driven in said first direction, but engaging said drive shaft to prevent rotation when driven in a second direction opposed to said first direction.    
     
     
         2 . A scroll compressor as recited in  claim 1 , wherein a clutch is positioned between said second scroll member and a housing member to prevent orbiting movement of said second scroll member in said second direction.  
     
     
         3 . A scroll compressor as recited in  claim 1 , wherein said device is positioned against an end of said shaft remote from said first and second scroll members.  
     
     
         4 . A scroll compressor as recited in  claim 3 , wherein said device includes a washer applying a thrust force along said shaft.  
     
     
         5 . A scroll compressor as recited in  claim 1 , wherein said device includes a tab which is movable within a housing, said tab abutting a stop on said housing when said shaft is driven in said first direction, and said tab being moved into a notch in said shaft when said shaft is driven in said second direction.  
     
     
         6 . A scroll compressor as recited in  claim 5 , wherein said washer is mounted within a bore of a housing member.  
     
     
         7 . A scroll compressor as recited in  claim 5 , wherein said housing also mounts a bearing at a remote end of said shaft.  
     
     
         8 . A scroll compressor as recited in  claim 1 , wherein there is a second device for preventing unpowered reverse rotation mounted adjacent to an upper end of said shaft.  
     
     
         9 . A scroll compressor comprising: 
 a first scroll member having a base and a generally spiral wrap extending from said base;    a second scroll member having a base and a generally spiral wrap extending from said base, said wraps of said first and second scroll members interfitting to define compression chambers;    a drive shaft for driving said second scroll member to orbit relative to said first scroll member in a first direction when said drive shaft is driven in a first direction; and    a washer positioned in abutting contact with an end of said shaft remote from said first and second scroll members, said washer having a tab extending upwardly toward said shaft, said tab being movable with said washer between an actuated and a non-actuated position, said tab abutting a housing stop when in said non-actuated position, and said tab catching an opening in said shaft when in said actuated position, said washer being driven to move said tab to said non-actuated position when said shaft is driven in said first direction, and said washer being driven to move said tab to said actuated position when said shaft is driven in a second direction opposed to said first direction.