Fluid machine

Abstract

A fluid machine includes a housing, an electric motor, a drive circuit that includes a heat-generating component and drives the electric motor, a cover that defines an accommodation chamber, which accommodates the drive circuit, with the housing, and a fastener that fastens the cover to the housing. The cover is configured to press the heat-generating component or a heat transfer member, to which heat of the heat-generating component is transferred, against the housing in a fastening direction of the fastener when fastened by the fastener. The fluid machine further includes a seal that is held between the first opposing surface of the housing and the second opposing surface of the cover in the direction intersecting the fastening direction of the fastener.

1 . A fluid machine comprising:
 a housing including a suction port through which fluid is drawn;   an electric motor accommodated in the housing;   a drive circuit including a heat-generating component, wherein the drive circuit drives the electric motor;   a cover arranged on an outer surface of the housing, wherein the cover defines an accommodation chamber, which accommodates the drive circuit, with the housing;   a fastener that fastens the cover to the housing, wherein
 the cover is configured to press the heat-generating component or a heat transfer member, to which heat of the heat-generating component is transferred, against the housing in a fastening direction of the fastener when fastened by the fastener, and 
 the housing includes a first opposing surface and the cover includes a second opposing surface that opposes the first opposing surface in a direction intersecting the fastening direction of the fastener; and 
   a seal arranged between the first opposing surface and the second opposing surface, wherein the seal is held between the first opposing surface and the second opposing surface in the direction intersecting the fastening direction of the fastener.   
     
     
         2 . The fluid machine according to  claim 1 , wherein:
 the cover and the housing are formed from a metal:   the cover includes
 a body including a circumferential wall and an end wall, wherein the circumferential wall includes a first end and a second end located at a side opposite to the first end, and the end wall is located at the first end of the circumferential wall, and 
 a flange projecting outward from the second end; 
   the fastener fastens the flange and the housing with the flange in contact with the housing,   the heat-generating component is located in the accommodation chamber that is defined by the body and the housing, and   the second opposing surface is part of an inner surface of the circumferential wall.   
     
     
         3 . The fluid machine according to  claim 1 , wherein
 the cover includes a body including a circumferential wall and an end wall, wherein the circumferential wall includes a first end and a second end located at a side opposite to the first end, and the end wall is located at the first end of the circumferential wall,   the fluid machine includes the heat transfer member,   the heat transfer member includes
 a base that is partially located between the heat-generating component and the housing, and 
 a post that extends from the base toward the end wall and contacts the end wall, and 
   when fastened by the fastener, the post is pressed by the end wall, which, in turn presses the heat transfer member against the housing.   
     
     
         4 . The fluid machine according to  claim 3 , wherein the cover is fastened to the housing with the fastener extending through the end wall, the post, and the base. 
     
     
         5 . The fluid machine according to  claim 3 , wherein
 the cover and the heat transfer member are formed from a metal,   the circumferential wall includes an inner surface including
 a first inner circumferential surface located at a side corresponding to the first end, 
 a second inner circumferential surface located at a side corresponding to the second end, and 
 a coupling surface that couples the first inner circumferential surface and the second inner circumferential surface, 
   a straight line that extends through a center of the first inner circumferential surface and connects two points on the first inner circumferential surface is shorter than a straight line that extends through a center of the second inner circumferential surface and connects two points on the second inner circumferential surface,   the housing includes a projection projecting from the outer surface of the housing toward the end wall, wherein the projection includes a distal end surface that contacts the base,   the second opposing surface is the second inner circumferential surface,   the first opposing surface is part of the projection, and   the base is held between the coupling surface and the distal end surface.   
     
     
         6 . The fluid machine according to  claim 3 , wherein
 the drive circuit includes a circuit board to which the heat-generating component is connected, and   the heat transfer member, the heat-generating component, and the circuit board are unitized with the heat-generating component in contact with the heat transfer member.   
     
     
         7 . The fluid machine according to  claim 3 , wherein
 the cover and the heat transfer member are formed from a metal,   the body includes an opening that opens toward the housing, wherein the opening is located at the second end,   the circumferential wall includes an inner surface including
 a first inner circumferential surface located at a side corresponding to the first end, 
 a second inner circumferential surface located at a side corresponding to the second end and having a larger diameter than the first inner circumferential surface, wherein the second inner circumferential surface forms the second opposing surface, and 
 a step surface located between the first inner circumferential surface and the second inner circumferential surface, 
   the housing includes a projection that projects from an end surface of the housing, wherein the projection includes a distal end surface that is in contact with the base, and the projection includes a side surface, which serves as the first opposing surface, located radially inward from the second inner circumferential surface,   the base is held between the step surface and the distal end surface, and   a metal-surrounded chamber surrounded by metal is defined by the first inner circumferential surface, the end surface, and the base, wherein the drive circuit is located in the metal-surrounded chamber, and the seal is located outside the metal-surrounded chamber.   
     
     
         8 . The fluid machine according to  claim 1 , wherein the fluid machine is a motor-driven compressor including a compression unit that compresses fluid drawn from the suction port when the electric motor is driven.