A scroll compressor includes a fixed scroll and a movable scroll. The fixed scroll has a spiral fixed-side wrap positioned upright on a surface of a fixed-side plate. The movable scroll is orbitably disposed to face the fixed scroll. The movable scroll has a spiral movable-side wrap positioned upright on a surface of a movable-side plate, with the movable-side wrap being configured to mesh with the fixed-side wrap. A side clearance is formed between a side surface of the fixed-side wrap and a side surface of the movable-side wrap so as to increase from an outer peripheral side toward an inner peripheral side of each of the wraps.

A scroll compressor includes a bush having a shaft part and a balance weight part. The shaft part is disposed between an orbiting bearing that supports an orbiting scroll, and an eccentric pin of a crankshaft. The balance weight part is secured to the outer periphery of the shaft part by shrink-fitting. The shaft part includes: a cylindrical body part which is fitted into the orbiting bearing, and into which the eccentric pin of the crankshaft is inserted; and a cylindrical coupling part which extends outward from an axial end portion of the body part, and to which the balance weight part is joined. The bush satisfies the following requirements:

1.2D2/D11.6, and(a)

1.0(D2D3)/(D4D2)E1/E23.5,(b)

where D1 is the outer diameter of the body part, D2 is the outer diameter of the coupling part, D3 is the inner diameter of the body part, D4 is the outer diameter of the balance weight part, E1 is the Young's modulus of the shaft part, and E2 is the Young's modulus of the balance weight part.

A driveshaft assembly for a compressor includes an unloader assembly and a driveshaft. The unloader assembly includes an unloader and a counterweight. The unloader assembly is rotationally supported by a bearing. The unloader includes a flank surface that is slidably engaged with a flank surface on the driveshaft.

Liquid ring systems are known for compressing gasses. However, known systems include moving surfaces that require high precision manufacturing. A valve arrangement for a liquid ring system comprising: a plurality of plates; a vane set; and a chamber set that comprises at least one chamber, wherein a first chamber of the chamber set comprises: a first valve, disposed on a first plate of the plurality of plates, which is configured to be closer to the first face of a first vane of the vane set than the second face of the second vane of the vane set; and a second valve, disposed on a second plate, which is configured to be closer to the second face of the second vane than the first face of the first vane.

To reduce surface pressure acting on a tip of a winding terminal portion of a spiral wall of an orbiting scroll in a scroll compressor. In a scroll compressor 10, a thrust plate 81 and a thrust sheet 82 capable of being elastically deformed are provided between an opposing surface 237 serving as a thrust receiving part and an orbiting base plate 521 of an orbiting scroll 52. A first sealing member 83 seals between the orbiting base plate 521 and the thrust sheet 82 and a second sealing member 84 having a diameter greater than that of the first sealing member 83 seals the opposing surface 237 of a second partition wall 232 and the thrust plate 81. A back pressure chamber H5 is partitioned from a suction pressure area (space H6) by the thrust plate 81, thrust sheet 82, the first sealing member 83, and the second sealing member 84. A circular concave portion 816 is formed on a surface of the thrust plate 81 on the thrust sheet 82 side.

A scroll compressor including an orbiting scroll that performs an orbiting motion; a fixed scroll coupled to the orbiting scroll so as to form a compression chamber; and a main frame that rotatably supports the orbiting scroll at an opposite side of the fixed scroll with the orbiting scroll interposed therebetween, and supportably connected to the fixed scroll. The fixed scroll is provided with a back pressure hole formed between a first back pressure chamber in which gas discharged from the compression chamber is received, and the compression chamber. The back pressure hole may communicate with the first back pressure chamber and the compression chamber on the basis of a predetermined pressure ratio of the compression chamber.

A supercharger constructed in accordance to one example of the present disclosure includes a housing, a first rotor, a second rotor and a rotor shaft assembly. The first and second rotors are received in cylindrical overlapping chambers of the housing. The first rotor has a central longitudinal passage. The rotor shaft assembly rotatably supports the first rotor and includes a first rotor shaft and a separate and distinct second rotor shaft. The first and second rotor shafts are press-fit into the central passage defined in the first rotor.

A rotary compressor includes a sealed longitudinal compressor housing which is provided with a discharge portion of a refrigerant at an upper portion thereof, is provided with an inlet portion of a refrigerant at a lower portion thereof, and in which lubricant oil is stored; a compressing unit which is disposed in the compressor housing, compresses a refrigerant sucked from the inlet portion and discharges the refrigerant from the discharge portion; a motor which is disposed in the compressor housing and drives the compressing unit via a rotation shaft; and an accumulator which is attached to a side portion of the compressor housing and is connected to the inlet portion of the refrigerant. When an inner diameter of a cylinder constituting the compressing unit is referred to as Dc, a height of the cylinder is referred to as Hc, and an eccentric amount of an eccentric portion of the rotation shaft is referred to as e, Dc, Hc, and e are set so that a value obtained by an expression (e+Hc).Math.(Dce).sup.1/3/(e.Math.Hc).sup.2/3 is less than 4.1.

A driveshaft assembly for a compressor includes an unloader assembly and a driveshaft. The unloader assembly includes an unloader and a counterweight. The unloader assembly is rotationally supported by a bearing. The unloader includes a flank surface that is slidably engaged with a flank surface on the driveshaft.

A fluid compressor system has a scavenge loss limiter that increases the efficiency of the fluid compressor system by reducing the compressed working fluid recirculated into the airend through a scavenge flow. The scavenge loss limiter includes a scavenge hole positioned at a discharge end face of a rotor cavity of the compressor housing. As a rotor of the compressor system rotates, the rotor may intermittently restrict the free-flowing scavenge flow returning from a lubricant separation tank. The rotor may be a male rotor having a plurality of male lobes. As the discharge end clearance between the rotor and the discharge end face is tightly controlled and monitored, a better control of the scavenge flow returning to the rotor cavity is achieved.