Rotary compressor arrangement (100) comprising a body (40) centered at a shaft axis (X) and a cylindrical piston (10) eccentrically arranged with respect to the body (40) such that a chamber is created between them, the arrangement (100) further comprising a satellite element (50) arranged at an offset axis (Y) and orbiting around the shaft axis (X) such that the orbiting of the satellite element (50) entrains in rotation around the shaft axis (X) the cylindrical piston (10) over the body (40), the relative distance between the axis (X, Y) being such that a contact between the body (40) and the cylindrical piston (10) within the chamber is ensured during rotation of the cylindrical piston (10).

The scroll-type compressor comprises a fixed scroll 320 and an orbiting scroll which are engaged with each other, a front housing 220 for accommodating the fixed scroll 320 and the orbiting scroll, and a rear housing 240 joined to the open end of the front housing 220. The fixed scroll 320 has the base plate 322 fitted into the front housing 220, and the flange 326 held at a joint surface between the front housing 220 and the rear housing 240. Additionally, at least one of the flange 326 of the fixed scroll 320 and the front housing 220 forms therein a recessed portion 326A or 220E which permits the fixed scroll 320 to be displaced in an axial direction toward the orbiting scroll due to a pressure difference acting on opposite surfaces of the base plate 322 of the fixed scroll 320.

A method for operating a progressive cavity pump wherein the stator has at least first and second active stator sections that are at different locations on the stator, comprising inserting a first rotor having a first active rotor section that is aligned with the first active stator section, and rotating the first rotor relative to the first active stator section such that the aligned first active rotor and stator sections generate a pumping force. Subsequently, the first rotor is removed and a second rotor is inserted having a second active rotor section that is aligned with the second active stator section, and rotating the second rotor relative to the second active stator section such that the aligned second active rotor and stator sections generate a pumping force.

A fluid machine is provided with a first rotor having a first rotor first working portion and a first rotor second working portion, a second rotor having a second rotor first working portion configured to mesh with the first rotor first working portion and a second rotor second working portion configured to mesh with the first rotor second working portion and rotate independently from the second rotor first working portion.

A screw compressor includes a casing, a drive shaft, a screw rotor, a gate rotor, a slide valve, and a slide valve driving mechanism having a hydropneumatic cylinder. The drive shaft has one end supported via a bearing on a bearing holder held by the casing. The other end is coupled to an electric motor. A compression chamber is defined by the gate rotor meshing with a helical move formed on the screw rotor. The hydropneumatic cylinder is located opposite to the screw rotor with respect to the bearing. The bearing holder has an outer peripheral surface configured as a guide surface guiding a sliding movement of the slide valve. The bearing holder has axial end portions. One of the axial end portions located opposite to the screw rotor constitutes a cylinder tube of the hydropneumatic cylinder to achieve integration of the bearing holder and the hydropneumatic cylinder.

There is provided an electric compressor to be fixed an object including a compression mechanism, an electric motor, a housing, a supporting member, and a plurality of vibration damping members. One of the housing and the supporting member has a recess and the other of the housing and the supporting member has a projection that is disposed in the recess and engaged with the recess to form a plurality of accommodating spaces on opposite sides of the projection, respectively. A filling rate of each vibration damping member in the corresponding accommodating space is changeable. There is also provided a method for manufacturing the electric compressor, including preparing a plurality of vibration damping members, choosing one of the vibration damping members, and providing the supporting member to the outer peripheral surface of the housing while accommodating the chosen vibration damping members in the respective accommodating spaces.

An eccentric screw pump for delivering solid-laden liquids includes a rotor and a stator within which the rotor is rotatably arranged. The rotor and stator are arranged and designed with respect to one another in such a way that at least one chamber is formed, which serves to transport the liquid. The eccentric screw pump has a drive motor for rotating the rotor, a control device for controlling the drive motor at least in a working state, in which the rotor is rotated, and an idle state, in which the rotor does not rotate, and an engagement unit, which is designed to set an engagement between the rotor and stator to an idle engagement in the idle state and to a working engagement in the working state. The idle engagement is less than the working engagement. A method for operating the eccentric screw pump is also disclosed.

Rotary compressor arrangement (100) comprising a body (40) centered at a shaft axis (X) and a cylindrical piston (10) eccentrically arranged with respect to the body (40) such that a chamber is created between them, the arrangement (100) further comprising a satellite element (50) arranged at an offset axis (Y) and orbiting around the shaft axis (X) such that the orbiting of the satellite element (50) entrains in rotation around the shaft axis (X) the cylindrical piston (10) over the body (40), the relative distance between the axis (X, Y) being such that a contact between the body (40) and the cylindrical piston (10) within the chamber is ensured during rotation of the cylindrical piston (10).

A method for operating a progressive cavity pump wherein the stator has at least first and second active stator sections that are at different locations on the stator, comprising inserting a first rotor having a first active rotor section that is aligned with the first active stator section, and rotating the first rotor relative to the first active stator section such that the aligned first active rotor and stator sections generate a pumping force. Subsequently, the first rotor is removed and a second rotor is inserted having a second active rotor section that is aligned with the second active stator section, and rotating the second rotor relative to the second active stator section such that the aligned second active rotor and stator sections generate a pumping force.

A screw compressor includes a casing, a drive shaft, a screw rotor, a gate rotor, a slide valve, and a slide valve driving mechanism having a hydropneumatic cylinder. The drive shaft has one end supported via a bearing on a bearing holder held by the casing. The other end is coupled to an electric motor. A compression chamber is defined by the gate rotor meshing with a helical groove formed on the screw rotor. The hydropneumatic cylinder is located opposite to the screw rotor with respect to the bearing. The bearing holder has an outer peripheral surface configured as a guide surface guiding a sliding movement of the slide valve. The bearing holder has axial end portions. One of the axial end portions located opposite to the screw rotor constitutes a cylinder tube of the hydropneumatic cylinder to achieve integration of the bearing holder and the hydropneumatic cylinder.