Provided is a motor rotor which, without changing an integral fastening structure relying on swage pins, increases resistance to the excessive excitation force of the motor rotor and which can easily prevent decreases in fastening strength; a motor that uses the motor rotor, and an electric compressor are also provided. This motor rotor is provided with a cylindrical rotor core comprising multiple laminated magnetic steel sheets, end plates and balance weights laminated on both ends of the rotor core, and multiple headed swage pins which are inserted from one side and which integrally fasten the rotor core, the end plates and the balance weights. The material of the balance weight arranged to the head of the swage pin is harder than that of the swage pin, and the material of the balance weight arranged to the swage part of the swage pin is softer than that of the swage pin.

A method and system is provided for pressure balancing one or more seals in machines such as expanders and/or compressors using the process fluid which is being expanded or compressed to provide the pressure for pressure balancing the other side of the one or more seals. The one or more seals may be part of a pressure containing chamber which may comprise a seal, a bearing and/or a gear on a rotating shaft common to the seal. An amount of pressure to be supplied to housing(s) for a machine so as to create a pressure cascade, and thereby dropping the pressure in each subsequent chamber as pressure approaches atmosphere. Pressure differentials may be directed to leak process fluid to the chamber into the process. Pressurized lube oil systems may be employed for balancing pressure and delivering lubricant to the seals, bearings and gears.

A compressor may include a first compression member, a second compression member, and a motor assembly. The second compression member is movable relative to the first compression member and cooperates with the first compression member to define a compression pocket therebetween. The motor assembly drives one of the first and second compression members relative to the other one of the first and second compression members. The motor assembly includes a stator and a rotor. The rotor is rotatable relative to the stator about a rotational axis. The stator surrounds the rotational axis. The rotor may include magnets that are arranged around the rotational axis. The magnets may be spaced apart from the stator in an axial direction that is parallel to the first rotational axis.

A cooling system is configured to operate in one of three modes, a DX mode of operation when outdoor air is too hot or too humid and the cooling system operates as a normal closed circuit system, a hybrid mode of operation when outside temperatures cool down and the cooling system operates as a partial reduced normal closed circuit system and a free cooling system, and a thermosiphon mode of operation when the outside temperature is below a predetermined temperature and the cooling system operates without the normal closed circuit system. The cooling system includes a scroll compressor unit having a main casing, a scroll compressor supported by the main casing, and a refrigerant pump supported by the main casing. The scroll compressor unit is configured to selectively engage the scroll compressor and the refrigerant pump to achieve one of the DX mode, the hybrid mode, and the thermosiphon mode.

The invention relates to a scroll compressor (10) and to a method for operating the scroll compressor (10). The scroll compressor (10) has a stator (15), an orbiter (20) which can be moved about an orbiter axis (55) relative to the stator (15), and a coupling device (50). The stator (15) and the orbiter (20) engage into each other and at least partly delimit at least one working area (105) for compressing a fluid (110) which can be filled into the working area (105). The coupling device (50) has a first coupling unit (60) which is arranged on the stator (15) and a second coupling unit (65) which is arranged on the orbiter (20) opposite the first coupling unit (60), wherein the first coupling unit (60) is magnetically coupled to the second coupling unit (65), and the second coupling unit (65) introduces a coupling torque (M.sub.K) which acts about the orbiter axis (55) into the orbiter (20).

A compressor may include a first compression member, a second compression member, and a motor assembly. The second compression member is movable relative to the first compression member and cooperates with the first compression member to define a compression pocket therebetween. The motor assembly drives one of the first and second compression members relative to the other one of the first and second compression members. The motor assembly includes a stator and a rotor. The rotor is rotatable relative to the stator about a rotational axis. The stator surrounds the rotational axis. The rotor may include magnets that are arranged around the rotational axis. The magnets may be spaced apart from the stator in an axial direction that is parallel to the first rotational axis.

A compressor may include a first compression member, a second compression member, and a motor assembly. The second compression member is movable relative to the first compression member and cooperates with the first compression member to define a compression pocket therebetween. The motor assembly drives one of the first and second compression members relative to the other one of the first and second compression members. The motor assembly includes a stator and a rotor. The rotor is rotatable relative to the stator about a rotational axis. The stator surrounds the rotational axis. The rotor may include magnets that are arranged around the rotational axis. The magnets may be spaced apart from the stator in an axial direction that is parallel to the first rotational axis.

An electric pump includes a case, and a motor that includes a rotor and a stator and is surrounded by the case. The case includes an introduction pipe portion for introducing a fluid and a discharge pipe portion for discharging the fluid. The rotor is disposed in a space surrounded by the case and the stator and communicating with the introduction pipe portion and the discharge pipe portion. The rotor includes a first blade member, a second blade member, and a relay portion. An outer diameter of the relay portion is smaller than an outer diameter of at least one of the first and second blade members. The relay portion is positioned between the first blade member and the second blade member.

A rotary compressor includes a cylinder that is coupled to an inner space of a casing and that defines a compression space, a first bearing and a second bearing located at upper and lower sides of the cylinder, a roller disposed eccentrically with respect to an inner circumferential surface of the cylinder to vary a volume of the compression space based on rotation, and a vane inserted into the roller to rotate together with the roller, and drawn out toward the inner circumferential surface of the cylinder during the rotation of the roller to partition the compression space into a plurality of compression chambers. A suction passage communicating with the compression space is defined in the first bearing or the second bearing, and a suction port communicating between the suction passage and the compression space is defined on a side surface of the cylinder.

An object is to ensure reliable engagement of a pin and an engagement hole (ring) serving as a rotation prevention mechanism in a scroll fluid machine in which a turn radius of an orbiting scroll is constant. A scroll-type compressor (10) according to the present invention is provided with: a fixed scroll (24); an orbiting scroll (22) that revolves with respect to the fixed scroll (24); a main shaft (14) that includes an input shaft (14a) to which a driving force is transmitted, and an eccentric shaft (14c) that is offset by a predetermined amount with respect to the input shaft (14a) and that transmits the driving force to the orbiting scroll (22); and a pin-and-ring mechanism (27) that is provided between the orbiting scroll (22) and a housing (11) and that prevents rotation of the orbiting scroll (22). When a turn radius of the eccentric shaft (14c) of the main shaft (14) is ?s and a turn radius of a pin (27a), which is determined by the pin (27a) and ring (27b), is ?pin, the pin-and-ring mechanism (27) satisfies ?s<?pin.