Scroll type fluid machine

Abstract

A scroll type fluid machine having a rotation-preventing member extending between at least one of a fixed scroll and a housing which form a non-orbiting part and a movable scroll and preventing rotation of the movable scroll, and also having a mechanism for making the rotation-preventing member movable, the mechanism being provided to the rotation-preventing member for permitting a movement of the rotation-preventing member itself which movement is required for the rotation-preventing member to permit an orbital movement of the movable scroll. The scroll type fluid machine, with the rotation-preventing mechanism for the movable scroll, can be easily assembled into a target assembly condition, and can be formed to be small-sized and light-weighted.

1 . A scroll type fluid machine comprising a fixed scroll, a movable scroll which engages said fixed scroll to form a fluid pocket being moved in a scroll radial direction, a crankshaft which engages said movable scroll to drive said movable scroll, and a housing which is provided with a bearing supporting said crankshaft, said movable scroll being orbited relative to said fixed scroll by a drive torque transmitted to through said crankshaft, characterized in that said fixed scroll and said housing form a non-orbiting part, and provided is a rotation-preventing member which extends between at least one of said fixed scroll and said housing forming said non-orbiting part and said movable scroll and which prevents said movable scroll from rotating, and also provided to said rotation-preventing member is a mechanism for making said rotation-preventing member movable, said mechanism permitting said rotation-preventing member's own movement required for permission of an orbital movement of said movable scroll by said rotation-preventing member. 
     
     
         2 . The scroll type fluid machine according to  claim 1 , wherein said rotation-preventing member comprises a member which is fixed to an outer circumferential section of said movable scroll and which extends from said outer circumferential section of said movable scroll radially outward, and said mechanism for making said rotation-preventing member movable is provided to at least one of said fixed scroll and said housing, and comprises a rotating-body space which has an axis line parallel with a main shaft section of said crankshaft and a rotating body which is rotatably fitted in said rotating-body space and which slidably supports said rotation-preventing member. 
     
     
         3 . The scroll type fluid machine according to  claim 2 , wherein said rotation-preventing member is constructed integrally with a scroll wall of said movable wall. 
     
     
         4 . The scroll type fluid machine according to  claim 2 , wherein said rotating body comprises a pair of columnar shoes each having an arc surface and a flat bottom surface, and supports said rotation-preventing member slidably between flat bottom surfaces facing to each other. 
     
     
         5 . The scroll type fluid machine according to  claim 2 , wherein a distance from a center axis of said rotating-body space to a center axis of said main shaft section of said crankshaft is set in a range of 1.5-15 times of an orbiting radius of said movable scroll. 
     
     
         6 . The scroll type fluid machine according to  claim 2 , wherein, when said rotating-body space is referred to as a cylindrical space having a diameter of D1, a thickness in a maximum thickness section determined based on said flat bottom surface with one of said cylindrical shoes is referred to as T1, a thickness in a maximum thickness section determined based on said flat bottom surface with the other of said cylindrical shoes is referred to as T2, and a thickness of said rotation-preventing member is referred to as Ts, they are set to satisfy a relation represented by the following equation:
     D 1> T 1+ T 2+ Ts.      
     
     
         7 . The scroll type fluid machine according to  claim 2 , wherein a back surface of said movable scroll slides on said housing and forms a space for containing a drive mechanism section of said crankshaft which is partitioned from a suction chamber, a lubricating oil route is provided for supplying lubricating oil from an oil sump formed below a discharge chamber into said drive mechanism section containing space, and said lubricating oil route is formed through said rotating-body space. 
     
     
         8 . The scroll type fluid machine according to  claim 2 , wherein said scroll type fluid machine is formed as a horizontal-type one in which said main shaft section of said crankshaft is extended in a horizontal direction at a time during operation. 
     
     
         9 . The scroll type fluid machine according to  claim 8 , wherein said rotating-body space is located above or below said fixed scroll. 
     
     
         10 . The scroll type fluid machine according to  claim 1 , wherein said rotation-preventing member comprises a member which is engaged free to rotate with an outer circumferential section of said movable scroll and which extends from said outer circumferential section of said movable scroll radially outward, and said mechanism for making said rotation-preventing member movable is provided to at least one of said fixed scroll and said housing, and comprises a hole for reciprocating sliding which extends in a direction orthogonal to a main shaft section of said crankshaft and which slidably supports said rotation-preventing member. 
     
     
         11 . The scroll type fluid machine according to  claim 10 , wherein an engagement section of said rotation-preventing member engaged free to rotate with said outer circumferential section of said movable scroll is located at a place from which a distance to a center axis of said main shaft section of said crankshaft in said movable scroll is set at 1.5 times or more of an orbiting radius of said movable scroll. 
     
     
         12 . The scroll type fluid machine according to  claim 10 , wherein a back surface of said movable scroll slides on said housing and forms a space for containing a drive mechanism section of said crankshaft which is partitioned from a suction chamber, and a lubricating oil route is provided for supplying lubricating oil from an oil sump formed below a discharge chamber into said drive mechanism section containing space, and said lubricating oil route is formed through said hole for reciprocating sliding. 
     
     
         13 . The scroll type fluid machine according to  claim 10 , wherein said scroll type fluid machine is formed as a horizontal-type one in which said main shaft section of said crankshaft is extended in a horizontal direction at a time during operation. 
     
     
         14 . The scroll type fluid machine according to  claim 1 , wherein a center of a bearing of a back surface of said movable scroll is coincident with the origin of a spiral curve forming a scroll wall, and a center of a main shaft section of said crankshaft supported rotatably by a bearing of said housing is coincident with the origin of a spiral curve forming a scroll wall of said fixed scroll. 
     
     
         15 . The scroll type fluid machine according to  claim 1 , wherein a bush integrated with a counterweight is interposed between a crankpin of said crankshaft and a bearing of a back surface of said movable scroll, so that torque is transmitted from said crankpin to said movable scroll at the same time that a centrifugal force in said movable scroll is cancelled to be decreased. 
     
     
         16 . The scroll type fluid machine according to  claim 1 , wherein wall thickness of a scroll wall of either or both of said movable scroll and said fixed scroll becomes smaller in an outward direction. 
     
     
         17 . The scroll type fluid machine according to  claim 1 , wherein said scroll type fluid machine is formed as a scroll type compressor or a scroll type expansion machine. 
     
     
         18 . The scroll type fluid machine according to  claim 1 , wherein said scroll type fluid machine is an automotive scroll type fluid machine which is mounted on a vehicle.