A rotary compressor that may include an upper or outboard bearing above the motor components and, in this case, includes an upper bearing plate having a structure that ensures bearing alignment when press fit with an upper cap and a center shell. In some implementations, a main bearing frame that secures and holds a main bearing has a structure that when press fit with a lower cap and center shell ensure bearing alignment. Some implementations include disposing a hermetic terminal and a discharge port a the side of the upper cap or center shell.

A pump assembly, fluid machinery, and a heat exchange device. The pump assembly includes: a lower flange; a lower friction-reducing ring; a cylinder, the lower friction-reducing ring being disposed inside the cylinder, and the lower flange being disposed below the cylinder; and a piston assembly arranged inside the cylinder and includes a piston sleeve and a piston slidably arranged inside the piston sleeve. The lower friction-reducing ring has a central hole. A position-limiting protrusion is disposed on a surface of the piston sleeve, which faces the lower flange. The limiting protrusion extends into the central hole of the lower friction-reducing ring, fits and is limited by the lower flange.

A centering process and fastening bolt are not required for assembling a fixed scroll and an orbiting scroll of a scroll compressor that includes a hermetically sealed container and a compression mechanism. The fixed scroll includes a cylindrical portion formed in a circumferential direction on an outer circumferential side of the fixed wrap, a flange provided in the circumferential direction further outside of the cylindrical portion, and a first hole provided in the flange in an axial direction. The frame includes an inner circumferential surface, a flange provided in the circumferential direction further outside of the inner circumferential surface, and a second hole in the axial direction which is provided in a position of the flange opposite to the first hole. A knock pin is inserted in the first and second holes to prevent the frame and the fixed scroll from being displaced in the rotational direction.

An outer gear and an inner gear expand and contract volume of pump chambers formed between both the gears, and rotate to suction fuel into the pump chambers and then discharge fuel from the pump chambers sequentially. The inner gear includes an insertion hole that is depressed along its axial direction. A joint member includes a main body portion that is fitted to a rotary shaft, a foot portion that extends from the main body portion along the axial direction and is inserted in the insertion hole with a clearance therebetween, and a protruding portion that protrudes from the foot portion toward a rotation progress side of the inner gear and has its width in the axial direction further narrowed toward a top portion of the protruding portion.

A scroll compressor includes a compression mechanism having fixed and movable scrolls forming a compression chamber, a motor to drive the movable scroll, a drive shaft, a casing, a housing accommodated inside the casing, and a floating member supported by the housing. The casing accommodates the compression mechanism, the motor, and the drive shaft. The floating member can be pushed toward the movable scroll by a pressure in a back pressure space formed between the floating member and the housing. The floating member may include a plurality of supported portions arranged circumferentially at three or more locations, and the housing may include a supporting portion supporting the supported portions. Alternatively, the floating member may include a body member and an outer peripheral member separate from the body member, the outer peripheral member mounted to an outer periphery of the body member, and the housing supports the outer peripheral member.

The scroll compressor (2) comprises a hermetic enclosure (3) comprising a midshell (4), an upper cap (5) and a baseplate (6), the baseplate (6) comprising a mounting base (32) having a plate shape and including a central opening (33), and a central cap (28) arranged within the central opening (33), the central cap (28) comprising a concave portion (29) and a first cylindrical rim portion (30) extending upwardly and having an outer diameter substantially corresponding to an inner diameter of the midshell (4); a compression unit (11) configured to compress refrigerant; and an electric motor (21) configured to drive the compression unit (11) via a drive shaft (19). The mounting base (32) comprises a second cylindrical rim portion (34) extending upwardly and surrounding the central opening (33), wherein an inner diameter of the second cylindrical rim portion (34) substantially corresponds to the inner diameter of the midshell (4) and to an outer diameter of the first cylindrical rim portion (30).

A pump includes a fluid inlet section, a fluid outlet section, a rotor axially between the fluid inlet section and the fluid outlet section, a center section radially inside of the rotor and a stator including electrical coils for generating electromagnetic flux for moving the rotor around the center section. The rotor and the center section define a fluid flow chamber radially therebetween. The rotor is rotatable about the center section by the electromagnetic flux generated by the electrical coils. An inlet control section is configured for regulating fluid flow from the fluid inlet section into the fluid flow chamber during rotation of the rotor inside of the stator about the center section. An outlet control section is configured for regulating fluid flow from the fluid flow chamber into the fluid outlet section during rotation of the rotor inside of the stator about the center section. The electrical coils are axially offset from the rotor.

An electric pump device includes a motor having a rotor and a stator portions, a pump portion and a housing. The stator portion has a stator core, and coils each having a winding portion and a crossover portion. The housing has a housing body portion having a tubular shape and extending in the axial direction, and a flange portion expanding radially outward from the outer peripheral surface of the housing body portion. The flange portion has an end surface that faces toward one side in the axial direction and is disposed in the axial direction between a first and a second virtual plane. The first and the second virtual planes pass through parts of the stator core, the winding portion, and the crossover portion located respectively closest to one and the other sides in the axial direction and expanding in a direction perpendicular to a central axis.

Provided is an electric pump device which includes a motor having a shaft extending along a first central axis, a pump portion driven by the motor, and a housing for housing the motor and the pump portion. The housing includes: a housing body portion which has a bottomed tube shape and extends in an axial direction, a flange portion which expands radially outward from an outer peripheral surface of the housing body portion, and a projection portion extending from a bottom portion of the housing body portion toward one axial side. A second central axis of the projection portion is arranged at a position shifted in a radial direction from the first central axis. The flange portion has convex portions projected from the end surface facing the one axial side of the flange portion toward the one axial side.

A pump includes a casing defining an interior volume. The pump casing includes at least one balancing plate that can be part of a wall of the pump casing with each balancing plate including a protruding portion having two recesses. Each recess is configured to accept one end of a fluid driver. The balancing plate aligns the fluid displacement members with respect to each other such that the fluid displacement members can pump the fluid when rotated. The balancing plates can include cooling grooves connecting the respective recesses. The cooling grooves ensure that some of the liquid being transferred in the internal volume is directed to bearings disposed in the recesses as the fluid drivers rotate.