PROBLEM TO BE SOLVED To improve controllability of a motor including a stator with two-split structure.

SOLUTION
A motor 400 includes a stator 460 disposed to surround an outer circumference of a rotor 440 which rotates integrally with a drive shaft 420. The stator 460 includes an inner core 462 having multiple protrusions 462B radially outwardly extending from an outer circumferential surface of a cylindrical portion 462A, and a cylindrical outer core 464 having its inner circumferential surface side attached to a top of the protrusion 462B. A connection portion (first connection portion 462F) as a part for connecting a side surface (first side surface 462D) of the protrusion 462B at an upstream side in a rotating direction of the rotor 440 and an outer circumferential surface of the cylindrical portion 462A has a rounded shape. A connection portion (second connection portion 462G) as a part for connecting a side surface (second side surface 462E) of the protrusion 462B at a downstream side in the rotating direction of the rotor 440 and the outer circumferential surface of the cylindrical portion 462A has a rounded shape. A radius r1 of the rounded shape of the first connection portion 462F is greater than a radius r2 of the rounded shape of the second connection portion 462G.

A fluid working system such as a pump for displacing a working fluid such as hydraulic fluid or a motor using a working fluid is provided. The system may have a positive displacement machine which includes one or more working chamber with displacement means such as a cylinder with a reciprocating piston. There are also two or more fluid ports to allow the working fluid to flow into and out of the working chamber. The working fluid flows from one fluid port means to another either being forced to do so when pumped or moving the piston when functioning as an engine. The fluid working system has associated therewith a non-dead compliance volume of a material such as syntactic foam. This compliance volume acts to smooth any pressure fluctuations within the working fluid system.

A scroll compressor includes an oil circulation pipe having one end inserted through a casing to be connected to an oil storage space inside the casing and another end connected to a suction passage for supplying refrigerant from outside of the casing to a compression chamber, an oil circulation valve disposed between the both ends of the oil circulation pipe to selectively open or close the oil circulation pipe, and a controller to control an opening or closing operation of the oil circulation pipe to reduce or eliminate frictional loss due to a shortage of oil by adjusting an oil level of the oil storage space at an initial operation.

A compressor may include a shell, first and second scroll members, a floating seal, a muffler plate, and a wear ring. The shell defines a discharge chamber and a suction chamber. The floating seal may sealingly engage the second scroll member. The muffler plate defines the discharge chamber and the suction chamber. The wear ring may sealingly engage the muffler plate and the floating seal such that the wear ring, the muffler plate, and the floating seal fluidly isolate the discharge chamber from the suction chamber. The muffler plate may include an axially facing surface that contacts the wear ring. The axially facing surface may include an annular recess. The wear ring may at least partially cover the annular recess. The annular recess may provide clearance between the muffler plate and the wear ring to allow the wear ring to deflect relative to the muffler plate during compressor operation.

A liquid pump of the present disclosure includes a container, a shaft, a bearing, a pump mechanism, a storage space, and a liquid supply passage. The shaft is disposed in the container. The bearing supports the shaft. The pump mechanism pumps a liquid by rotation of the shaft. The storage space is defined in the container at a position outside the pump mechanism. The storage space stores the liquid to be taken into the pump mechanism or the liquid to be discharged to outside of the container after being expelled from the pump mechanism. The liquid supply passage is a flow path including an inlet open to the storage space and supplying the liquid stored in the storage space to the bearing.

A device for compression of a gaseous fluid, in particular of a refrigerant. The device comprises a housing with a suction pressure chamber and a high pressure chamber, a compression mechanism as well as a configuration developed in the proximity of the high pressure chamber, for the separation of a control mass flow from a fluid-lubricant mixture for the control of the compression mechanism. The configuration is developed and disposed with a first flow duct for diverting a main mass flow of the compressed fluid-lubricant mixture from the device and a second flow duct for conducting the control mass flow within the device to the suction pressure chamber in such manner as to separate a mass flow of the gaseous fluid as a control mass flow. A method for the separation of a control mass flow is also provided.

The purpose of the present invention is to provide a scroll-type fluid machine for which maintenance can easily be performed in necessary locations, and a maintenance method for said fluid machine. The present invention provides a scroll-type fluid machined characterized by being provided with a main body unit for compressing a fluid, and a motor unit for driving the main body unit; the main body unit having a fixed scroll, a revolving scroll, a main body casing, and an autorotation-preventing mechanism that is held by the revolving scroll and the main body casing and that prevents autorotation of the revolving scroll; the motor unit having a rotor, a stator for causing the rotor to rotate, a shaft that rotates integrally with the rotor, a motor cover for housing the rotor and the stator, and a main bearing that is secured to the interior by the motor cover and that supports the shaft; a distal end of the shaft having an eccentric part; the main body unit and the motor unit being connected via the eccentric part; and the main body casing and the motor cover being fastened by a fastening member.

A scroll compressor includes oil in an oil storage space that is brought into direct contact with and stirred with a discharge refrigerant. The scroll compressor includes a fixed scroll, an orbiting scroll coupled to one side of the fixed scroll, and a discharge cover coupled to another side of the fixed scroll and provided with a muffler hole communicating with a refrigerant discharge space and the oil storage space.

A scroll compressor includes a first oil supply passage communicating with a first compression chamber formed between an inner circumferential surface of a fixed wrap and an outer circumferential surface of an orbiting wrap, and a second oil supply passage separated from the first oil supply passage and communicating with a second compression chamber formed between an outer circumferential surface of the fixed wrap and an inner circumferential surface of the orbiting wrap, wherein the first oil supply passage includes an oil supply guide portion provided in a thrust surface of the fixed scroll in contact with the orbiting scroll to define a part of the first oil supply passage, whereby communication between the first and second compression chambers can be prevented, thereby suppressing leakage between the compression chambers, stabilizing behavior of the orbiting scroll, and facilitating formation of the orbiting scroll.

A pump as provided includes an inlet, an outlet, and a scroll pumping element. The scroll pumping element includes a fixed scroll component having one or more fixed scrolls and orbiting scroll component having one or more orbiting scrolls for fluid pumping. The fixed scroll component and the orbiting scroll component are arranged so as to be capable of providing pressurized fluid to a thrust bearing and prevent contact between the fixed scroll component and the orbiting scroll component.