Abstract: The present invention provides a positive displacement dry pump comprising: a plurality of vacuum pumping stages comprising a respective plurality of pumping mechanisms driven by one or more drive shafts for pumping fluid in series through the pumping stages from a pump inlet at the high vacuum stage to a pump outlet at the low vacuum stage; a lubrication chamber housing a bearing assembly for supporting the drive shaft for rotational movement, the drive shaft extending from the high vacuum stage to the lubrication chamber through an opening of a head plate of the lubrication chamber; an inter-stage purge port through which gas can enter the pump at an inter-stage location downstream of the high vacuum stage and pass only through the or each vacuum pumping stage downstream of the inter-stage port; a lubrication chamber purge port located in the lubrication chamber through which purge gas can flow from a source of purge gas; wherein the inter-stage port is connected to the lubrication chamber for controlling t

Abstract: A two-stage screw compressor has a low-pressure stage screw compressor and a high-pressure stage screw compressor integrally constructed. Compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. A method of supplying lubrication oil prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor. As a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.

Abstract: A rotary hydraulic actuator includes a housing defining a chamber, a first boss, and a port block with a bore communicating with the chamber. The port block includes rotor supply and drain ports communicating with the bore, and a stator port communicating with the chamber through a stator hole in the boss. A rotor mounted in the internal chamber includes: a body with a laterally-extending arm; a first stub shaft received in the bore, the first stub shaft including base slots passing laterally therethrough; a first rotor port disposed in the arm in communication with the internal chamber, and oriented in a tangential direction relative to an axis of rotation; and internal passages which interconnect the rotor base slots and the first rotor port. Passages in the port block communicate with the bore and interconnect the rotor supply and drain ports at a first angular position of the rotor.

Abstract: A pumping device and method are described. The pumping device comprises a dry rough vacuum pump equipped with a gas inlet connected to a vacuum chamber, a gas outlet leading to a conduit and an ejector. The pumping method comprises pumping gases contained in the vacuum chamber using the dry rough vacuum pump through the gas inlet, measuring electric power consumed by the dry rough vacuum pump and the pressure of the gases in the conduit, starting the ejector, when the pressure of the gases at the outlet and the electrical power consumed cross respective set point values as they rise and stopping the ejector when the electric power consumed and the pressure of the gases in the conduit at the outlet cross respective set point values as they fall.

Abstract: A pump device for a frozen product machine includes a pump casing, first and second rotor gear, and a sealing arrangement. The first and second rotor gears fit in a pumping cavity of the pump casing in a rotatably movable manner that creates a suction effect for pumping and mixing liquid mixture with air to produce a mixture product. The sealing arrangement includes a plurality of sealing elements provided between two outer side surfaces of the first and second rotor gears and inner side surfaces of the pump casing for ensuring the liquid mixture and air being sealed and mixed within the pumping cavity through the first and second rotor gears and for preventing the first and second rotor gears from being direct-surface contact of the pump casing.

Abstract: A compressor system includes a lubricant reservoir, a screw compressor, and a valve. The screw compressor includes a housing defining a compression chamber having a suction port, a discharge port, a first lubricant feed port located between the suction port and the discharge port, and a second lubricant feed port located between the discharge port and the first lubricant feed port. The valve is in fluid communication with the lubricant reservoir, the first lubricant feed port via a first lubricant feed passageway, and the second lubricant feed port via a second lubricant feed passageway. The valve is movable between a first position and a second position. In the first position, the valve fluidly connects the lubricant reservoir to the first lubricant feed passageway to direct lubricant to the first lubricant feed port. In the second position, the valve fluidly connects the lubricant reservoir to the second lubricant feed passageway to direct lubricant to the second lubricant feed port.

Abstract: Methods for controlling the net-displacement of a rotary fluid pressure device are disclosed. One of the net-displacement control methods (47) includes obtaining a desired input parameter (23) and a relative position (21) of a first member (43) and a second member (35) of a fluid displacement mechanism. A determination of a first and second output value is then made for each of a plurality of volume chambers (45) when the volume chambers (45) are supplied with fluid at fluid inlet and fluid outlet conditions, respectively. A total output value is then computed for each of a plurality of control valve configurations (63) and compared to the desired input parameter (23). The control valve configuration (63) with the total output value most similar to the desired input parameter (23) is then selected. A plurality of control valves (15) are then actuated in accordance with the selected control valve configuration (63).

Abstract: A vane compressor has a plurality of vanes that are radially translatable and have outer ends. The vanes create zones between each pair of adjacent vanes, each zone having a given area. The vane compressor also has an axis about which the vanes rotate and an outlet for expelling compressed fluid. A first zone immediately following a second zone, which is in register with the outlet, has the same area as the second zone.

Abstract: The present invention relates to a system for improving the performance of a rotary engine comprising at least one of a piston having at least one piston vane configured to rotate. A peddle block is positioned in the pathway of the piston vane, wherein as the piston vane approaches the peddle block a secondary exhaust pressure increases against the piston vane surface, the secondary exhaust pressure, in part, causes the piston vane to rotate and self-align for a subsequent cycle. A variable orifice secondary exhaust port selectively vents at least a portion of the secondary exhaust pressure, away from the piston vane setting an optimal rotational speed of the piston vane, improving performance of the rotary engine. Other exemplary embodiments include turbo-charging the rotary engine by increasing the secondary exhaust pressure, increasing the piston vane rotation, and increasing the amount of secondary exhaust pressure that is recirculated.

Abstract: A gerotor assembly includes a star, a ring, and an annular plug member, as well as an o-ring. The star member defines a center opening of a first diameter which is connectable to a low-pressure fluid reservoir. The ring member circumscribes the star member. The ring member defines, in conjunction with a stationary end cap of a fluid control device, a fluid channel connectable to a high-pressure fluid supply. The plug member is circumscribed by the star member, and defines a center bore of a second diameter less than the first diameter. The o-ring is positioned between the star and the plug members. The plug member forms a fluid seal against the end cap. A fluid control device includes the above gerotor assembly and a valve housing section. A method of assembling the gerotor assembly and fluid control device are also disclosed.

Abstract: A scroll compressor and assembly includes a suction duct to direct refrigerant from the housing inlet to a location upstream of a motor. Additionally, the suction duct includes drain ports that act to drain oil received in the suction duct into the oil sump. This can be used for filling and charging the oil sump with oil initially by using the common refrigerant inlet port through the housing and also acts to collect coalesced oil from oil mist generated by operation of the scroll compressor in a refrigeration system and likewise drain the lubricant oil into the lubricant sump.

Abstract: A rotary pump having a variable delivery volume, comprising: a casing; a delivery chamber formed in the casing; at least one delivery rotor which is rotatable in the delivery chamber; an actuating member which is arranged facing a front face of the delivery rotor or surrounds the delivery rotor, and is moveable in the casing for adjusting the delivery volume; the actuating member chargeable with an actuating force which is dependent on a fluid requirement; a track which is formed in the casing and guides the actuating member on an actuating member sliding surface in a sliding contact; and a sliding material which forms at least one of the track and the actuating member sliding surface.

Abstract: A method for restoring the registry of opposed shafts that carry meshing pump teeth inside a polymer pump that contains polymer without removing polymer from within the pump, the method using an asymmetric pattern of apertures in the shaft ends and a template having a pattern of holes that matches the pattern of apertures, and dowels that closely fit the holes and apertures.

Abstract: An internal gear fluidic machine, in particular a pump for the lubrication circuit of a motor vehicle engine, comprises an operating part including an external gear (2) and an internal gear (4), which is housed within an axial cavity (25) of the external gear (2) and meshes with the latter. The external gear (2) is associated with a translating mechanism (8, 22), arranged to cause an axial sliding thereof relative to the internal gear (4) in order to vary the capacity and the fluid flow rate of the machine. The translating mechanism (8, 22) defines a first capacity, adjustment space (24) in communication with a high pressure chamber (48) of the machine, and a second capacity adjustment space (15) where pressure conditions exist that are dependent on the operating conditions of an element, different from the high pressure chamber (48), of a fluidic circuit in which the machine (1) is connected.

Abstract: A compressor may include a shell, first and second scroll members, and a seal assembly. The shell defines a first and second pressure regions. The first scroll member may include a first end plate defining a chamber. The seal assembly may surround the discharge passage and fluidly separate the first and second pressure regions from each other. The seal assembly may include first and second sealing members. The first sealing member may prevent communication between the chamber and the second pressure region when a first fluid pressure within the second pressure region is higher than a second fluid pressure within the chamber. The first sealing member may define a leakage path when the first fluid pressure is lower than the second fluid pressure. The second sealing member may fluidly separate the chamber and the second pressure region when the first fluid pressure is lower than the second fluid pressure.

Abstract: A scroll compressor may be provided with a check valve interposed between a balance chamber and a discharge chamber. The check valve may allow balance chamber pressure to remain low during start-up of the compressor. Low balance chamber pressure may allow an orbiting scroll to remain unclamped to a fixed scroll thereby reducing torque required to initiate rotation of the orbiting scroll. After steady-state operational speed is reached the check valve may close and the scrolls may be clamped together to produce a desired steady-state operating condition for the compressor.

Abstract: A compressor (10) comprises counter rotating and intermeshing twisted rotors (18) and (20) disposed in a housing having an air intake plate (28) and an outlet (16). The outlet (16) has a first edge (60) and a second edge (70) which nm parallel with a length of the rotors (18) and (20) respectively. A gap (62) is formed in the outlet near a junction of the edges (60) and (70). Air which is compressed by the rotors (18) and (20) is able to bleed through the gap (62) in advance of trailing edges of lobes of at least one of the rotors (18) passing its corresponding edge (60). Also the rotors (18), (20) are arranged so that the trailing edge of a lobe of rotor (18) passes edge (60) before a trailing edge of a lobe of rotor (20) passes edge (70).

Abstract: A positive displacement rotary machine with a body having an internal spherical working surface divided into bypass and propulsion areas, a rotor with a working rotational surface, a ring working cavity formed by the working surfaces of the body and rotor, and a C-shaped separator mounted in part of the cavity at an angle to a plane of the rotor rotation. The cavity is partitioned by the separator at the bypass area, and the working medium openings are located from opposite sides of the separator. The working surface of the rotor has at least one slot. In each slot is mounted a piston capable of sealing the working cavity, and performing rotational oscillations in a slot plane. The piston is at least in the form of a part of a disk and has at least one through-cutout for the separator passage, and can seal the through-cutout at the propulsion area.

Abstract: A stepper motor suitable for use in a medical imaging environment has (a) a cylindrical central gear having an external surface with circumferentially distributed and radially directed teeth, (b) a shaft for mounting the central gear such that it is constrained to move in rotational motion about its centerline, (c) a cylindrical hoop gear having a bore with an internal surface having circumferentially distributed and radially directed teeth, (d) level arm crank mechanisms for mounting the hoop gear such that it is constrained to move in translational-circular motion about the central gear's centerline, wherein this central gear is further configured to fit within the hoop gear's bore in such a manner that a plurality of the central gear and hoop gear teeth intermesh and cooperate so that the planetary movement of the hoop gear causes the central gear to rotate, and (e) piston mechanisms for applying a fluid pressure driven force to specified points on the hoop gear so as to cause its movement.

Abstract: The invention is a compression method having characteristics of smooth compression and internal cooling of the gas. Embodiments of the invention employ a cylindrical chamber and an orbiting rotor to create a moving duct or chamber whose walls converge, relative to a static gas packet drawn into the moving duct, at a “pinch point”. Preferably the closing speed of the walls is subsonic and the speed of the pinch point is supersonic. This enables high pressure to co-exist, at the narrowing end of the duct, with low pressure elsewhere in the duct, because of the pressure information barrier produced by the supersonic advance of the pinch point. The invention also discloses means for providing gas inlet and outlet functionality, and means for providing a variable flow compressor.

Abstract: A rotary fluid device having a housing that defines a pumping chamber, a shaft disposed in the housing, and a rotor disposed in the pumping chamber and engaged with the shaft. The rotor includes a body which defines a bore that includes an oblique tapered surface. A pivot line is disposed along the tapered surface. The pivot line is a circumferential line at which the rotor pivots. A method for manufacturing a rotor includes turning an outer peripheral surface of the rotor. A bore is formed in the rotor. The bore includes an oblique tapered surface that has a pivot line disposed along the tapered surface, wherein the pivot line is a circumferential line at which the rotor pivots.

Abstract: A positive displacement compressor designed for near isothermal compression. A rotor includes a curved sealing portion that coincides with a in an interior rotor casing wall. Liquid injectors provide cooling liquid. A gate moves within the compression chamber to either make contact with or be proximate to the rotor as it turns. Gate positioning systems position the gate in this manner, taking into account the shape of the rotor. Outlet valves allow for expulsion of liquids and compressed gas. The unique geometry and relationship between the parts provides for efficiencies and higher pressures not previously found in existing compressor designs.

Abstract: The invention relates to a rotor for a positive displacement rotary pump. The rotor comprises a hub with an aperture and a center axis through aperture and at least 2 lobes radially extending from hub and in a direction essentially perpendicular to the axis of hub. The rotor comprises a core of a first polymer material and a cover of a second polymer material, which second polymer material has a hardness which is lower than the first polymer material. The first and the second polymer materials are connected to each other. The hub or the major part of the hub is preferably provided by the core, whereas at least a part of the lobes is provided by the cover. The invention also relates to a method of providing the rotor and a pump comprising the rotor.

Abstract: Methods, devices, and systems are disclosed for combining fluids of different pressures and flow rates in, for example, gas gathering systems, gas wells, and other areas in which independently powered compressors are not desired. Methods, devices, and systems for turning a shaft are also provided, as are methods, devices, and systems for dropping pressure in a gas line.

Abstract: A scroll component including a spiral scroll wrap, a baseplate having a first major surface coupled to the scroll wrap and a second opposing major surface comprising a protruding pilot extending a distance from the baseplate, and a hub fastened to the baseplate adjacent to the protruding pilot. A method of forming a scroll compressor element is also provided.

Abstract: The present technology is directed generally to rotary displacement systems and associated methods of use and manufacture. The systems can be used to compress and/or expand compressible fluids. In some embodiments, the rotary displacement systems include a chamber housing having a pressure-modifying chamber with a first port and a second port, a first passageway in fluid communication with the chamber via the first port, and a second passageway in fluid communication with the chamber via the second port. The systems can further include a shaft positioned within the chamber housing and rotatable relative to the chamber housing about a rotational axis, and a rotor comprising no more than two lobes.

Abstract: The present technology is directed generally to rotary displacement systems and associated methods of use and manufacture. The systems can be used to compress and/or expand compressible fluids. In some embodiments, the rotary displacement systems include a chamber housing having a pressure-modifying chamber with a first port and a second port, a first passageway in fluid communication with the chamber via the first port, and a second passageway in fluid communication with the chamber via the second port. The systems can further include a shaft positioned within the chamber housing and rotatable relative to the chamber housing about a rotational axis, and a rotor comprising no more than two lobes.

Abstract: A scroll compressor includes scroll compressor bodies with axial tip seals projecting from the respective scroll ribs of fixed and movable scroll compressor bodies. An extended thrust region is provided in surrounding relation to an inner axial tip sealing region to provide for carrying thrust loads in the event that the scroll compressor bodies are forced axially together. Part of the thrust region may carry a tip seal, while another part may be free of a tip seal. This provides for at least a nominal reverse operation capability.

Abstract: The invention comprises a rotary engine method and apparatus configured with a lip seal. A lip seal restricts fuel flow from a fuel compartment to a non-fuel compartment and/or fuel flow between fuel chambers, such as between a reference expansion chamber and any of an engine: rotor, vane, housing, and/or a leading or trailing expansion chamber. In separate states, high pressure and low pressure force sealing movement of the lip seal, respectively. The lip seal is optionally used in combination with a cap seal to form a dynamic seal. The dynamic seals ability to track a noncircular path are particularly beneficial for use in a rotary engine having an offset rotor and with a non-circular inner rotary engine compartment having engine wall cut-outs and/or build-ups. The dynamic sealing forces further provide cap sealing forces over a range of temperatures, pressures, fuel flow rates, varying loads, and operating engine rotation rates.

Abstract: An oil-free lubrication centrifugal refrigerant compressor for compressing low-pressure refrigerant into high-pressure refrigerant, includes: a housing; a refrigerant pathway; a compression module; a radial bearing; a first conducting member, collecting troughs and a first exhaust member.

Abstract: A compressor (20) has at least a first rotor (26; 28) at least partially within a bore (276; 278) of a housing. A slide valve element (102; 300) is positioned at least partially within a channel (200; 301) in the housing and has a first surface facing the first rotor. The slide valve element includes a body (268; 302) and a coating (270; 306) on the body. The coating forms the first surface.

Abstract: A scroll compressor includes a baffle member in a high pressure region of the housing where compressed fluid is stored. The baffle serves to carry and transfer pressure loads away from the central region to an outer periphery region where such loads can be transferred to the outer housing. Deflection, stress and wear on the scroll compressor bodies may be reduced.

Abstract: A new type of progressive cavity compressor is intended primarily for 3 to 10 ton vapor-cycle air conditioning systems. Major working section elements include a rotor, a stator, inlet ports, an outlet endplate, and outlet check valves. The helical rotor is driven in an eccentric orbital path inside the helical stator. In the preferred embodiment, the rotor and stator helices have varying (non-uniform) pitch in the working section. Rotor-stator running clearances are tight, to minimize leakage. Two outlet check valves regulate refrigerant discharge flow and pressure. Efficient compression is provided over a wide range of compression ratios, corresponding to a wide range of ambient temperatures in an air conditioning application. The invention can improve the energy efficiency of air conditioning systems, especially at off-design conditions.

Abstract: The invention comprises a rotary engine method and apparatus configured with a cap seal. A cap seal restricts fuel flow from a fuel compartment to a non-fuel compartment and/or fuel flow between fuel chambers, such as between a reference expansion chamber and any of an engine: rotor, vane, housing, and/or a leading or trailing expansion chamber. Means for providing cap sealing force to seal the cap against a rotary engine housing element comprise one or more of: a spring force, a magnetic force, a deformable seal force, and a fuel force. The dynamic caps ability to track a noncircular path are particularly beneficial for use in a rotary engine having an offset rotor and with a non-circular inner rotary engine compartment having engine wall cut-outs and/or build-ups. The dynamic sealing forces further provide cap sealing forces over a range of temperatures, pressures, fuel flow rates, and operating engine rotation rates.

Abstract: A rotary engine using a swing vane separating expansion chambers is provided for operation with a pressurized fuel or fuel expanding during a rotation of the engine. A swing vane pivots about a pivot point on the rotor yielding an expansion chamber separator ranging from the width of the swing vane to the length of the swing vane. The swing vane optionally slidingly extends to dynamically lengthen or shorten the length of the swing vane. The combination of the pivoting and the sliding of the vane allows for use of a double offset rotor in the rotary engine and the use of rotary engine housing wall cut-outs and/or buildups to expand rotary engine expansion chamber volumes with engine rotation yielding corresponding increases in rotary engine power and/or efficiency.

Abstract: The invention relates to a pumping system (3) for pumping fluid. The pumping system (3) comprises a first pumping unit (1) comprising a first flow path (4) and a second pumping unit (2) comprising a second flow path (5). The fluid pumped by the first pumping unit (4) is guided through the first flow path (4), and the fluid pumped by the second pumping unit (2) is guided through the second flow path (5). The first pumping unit (1) and the second pumping unit (2) are functionally coupled. The first flow path (4) and the second flow path (5) are adapted to be functionally independent from each other.

Abstract: A rotary machine is described with a vane carried by a rotor in a housing. The vane includes: a central vane axis extending radially outward along a y-axis from a center of the rotor through the vane to the housing. A centrifugal force of the vane against the housing is primarily distributed with a first sealing element mounted on an end of the vane, such as a rotatable element supported by a rigid support. The rigid structure of the first sealing element facilitates use of a second flexible sealing element mounted on the vane end. The second flexible sealing element performs as a sliding seal between a trailing expansion chamber and a leading expansion chamber on opposite sides of the vane. The rigid seal and the flexible sliding seal typically function independently of each other as separate constituents of the tip or end of a given vane.

Abstract: A rotor engine is provided for operation with a fuel expanding during a power stroke. To aid power stroke efficiency, the rotary engine contains a vane, where a tip of the vane includes one or more of: a rolling element configured to move with the vane, a bearing for bearing the force of the vane applied to the inner housing, a seal for providing a seal between a leading chamber and an expansion chamber, a pressure relief cut for reducing pressure build-up between vane wings and an inner wall of the rotor engine housing; and/or a booster enhancing pressure equalization above and below a vane wing. The vane reduces vibration of the vane-tips against the inner wall of the housing of the rotary engine during operation of the engine.

Abstract: A pump assembly includes a housing having a chamber in communication with an inlet and an outlet. A rotating ring, variable displacement vane pump is received in the chamber. The pump, and particularly the rotating ring, is supported by a fluid bearing in the chamber. A control is provided for selectively altering fluid flow to the bearing in response to one of hydrodynamic bearing pressure, boost flow pressure, and the pump stroke.

Abstract: A scroll compressor includes scroll compressor bodies with axial tip seals projecting from the respective scroll ribs of fixed and movable scroll compressor bodies. An extended thrust region is provided in surrounding relation to an inner axial tip sealing region to provide for carrying thrust loads in the event that the scroll compressor bodies are forced axially together. Part of the thrust region may carry a tip seal, while another part may be free of a tip seal. This provides for at least a nominal reverse operation capability.

Abstract: A rotary engine is described including: (1) a rotor located within a housing, the rotor configured with a plurality of rotor vane slots; (2) a vane separating an interior space between the rotor and the housing into at least a trailing chamber and a leading chamber, where the vane slidingly engages a rotor vane slot; (3) a first passage through the vane, the first passage including a first exit port into the rotationally trailing chamber; and (4) a second exit port to the rotationally trailing chamber, where the first exit port and the second exit port connect to any of: (a) the first passage through the vane and (b) the first passage and a second passage through the vane, respectively. Optionally, one or more seals affixed to the vane and/or the rotor valve the first passage, the second passage, a vane wingtip, and/or a conduit through the rotor.

Abstract: An oil pump including a first housing having a rotation shaft insertion hole, a cam ring, a pump element, a rotation shaft rotatably extending through the rotation shaft insertion hole, a second housing disposed on the cam ring, wherein the cam ring is placed in a position relative to the rotation shaft insertion hole of the first housing by using a jig, and the cam ring includes a clamped portion that is clamped by a cam ring holding device, while the first housing and the second housing are fixed to each other after placing the cam ring in the position relative to the rotation shaft insertion hole by using the jig. Alternatively, the oil pump including a fixing means for fixing the cam ring to the pump body instead of the clamped portion.

Abstract: A pump rotor for a screw pump includes a shaft, a first set of threads disposed on a portion of an outer surface of the shaft, at least one thread of the first set of threads including a groove disposed on an end portion thereof, and a ring seal disposed on the groove such that the ring seal is configured to protrude outwardly from the groove and to rest against an inner surface of a liner of the screw pump, and the groove is sized so as to allow the ring seal to move radially with respect to the plurality of threads as the rotor is deflected.

Abstract: An engine is described for operation on a fuel expanding about adiabatically in a power stroke of the engine. To aid the power stroke efficiency, the rotary engine contains one or more of a rotor configured to rotate in a stator, the rotor offset along both an x-axis and a y-axis relative to a center of the stator, a vane configured to span a distance between the rotor and the stator, where the inner wall of the stator further comprises at least one of: a first cut-out in the housing at the initiation of the power stroke, use of a build-up in the housing at the end of the power stroke, and/or use of a second cut-out in the housing at the completion of rotation of the rotor in the engine. The engine yields a cross-sectional area expanding during a portion of the power stroke at about the Fibonacci ratio.

Abstract: The present invention provides a pump system comprising a bearing housing coupled to a pump liner, the pump liner defining a fluid conduit, the pump liner comprising a fluid inlet and a fluid outlet; and at least one rotor having a first rotor portion and a second rotor portion, the first rotor portion being disposed within the fluid conduit and the second rotor portion being disposed within the bearing housing; the first rotor portion comprising a first conveying stage adjacent to the bearing housing, and a second conveying stage adjacent to the first conveying stage, the first and second conveying stages being configured to convey a fluid, the first conveying stage being configured to convey the fluid from the bearing housing into the fluid conduit. The new pump systems rely on a dynamic restriction to reduce the need for mechanical seals between bearing housings and raw process fluid.

Abstract: Scroll pumping apparatus includes a first scroll element and a second scroll element; a drive mechanism operatively coupled to the second scroll element for producing orbiting motion of the second scroll element relative to the first scroll element, the drive mechanism having an axis of rotation; and an isolation element to isolate a first volume and a second volume in the scroll pumping apparatus. The isolation element includes a first resilient annular member coupled, directly or indirectly, to the first scroll element, a second resilient annular member coupled, directly or indirectly, to the second scroll element, and a tubular member coupled between the first and second annular members.

Abstract: A valve for selectively allowing the return of oil from a discharge plenum to a suction plenum includes a passage which is selectively opened or blocked by a valve spool. The valve spool sees a pressure from a discharge pressure location upstream of a discharge check valve on one face, and a discharge pressure from a discharge plenum on an opposed face. While the compressor is running, the two pressures should be relatively equal. The face which sees the pressure from the chamber upstream of the check valve is larger than the face which sees the pressure from the discharge plenum. Thus, when the compressor is running, the valve spool is biased to a first position at which it allows oil return from the discharge plenum to the suction plenum. However, upon shutdown of the compressor, the pressure in the chamber upstream of the discharge valve drops. The valve spool will be driven to a second position at which it blocks communication for oil return.

Abstract: An eccentric screw pump or an eccentric screw motor has a rotor formed from at least a tubular jacket with at least two layers. The outer layer of the jacket consists of a material that is abrasion-resistant and/or corrosion-resistant.

Abstract: A progressing cavity pump assembly includes a collar assembly connecting a housing and a tubing string, with the collar having an inside diameter upset and the rotor having a rotor head axially spaced from a rotor helix, with the rotor head having an outer diameter forming a stop adapted to land on the inside diameter upset. A method of timing a progressing cavity pump assembly includes providing a collar assembly having an inside diameter upset, movably connecting the collar assembly and the housing, providing a rotor having a rotor head axially spaced from a rotor helix, with the rotor head having an outer diameter forming a stop, selectively adjusting the relative position of the collar assembly and the housing to form a pathway substantially corresponding to the rotor helix, landing the stop on the inside diameter upset, and fixing the relative position of the collar assembly and the housing.

Abstract: The invention relates to a rotary lobe pump for conveying solids-laden fluids engendered in agriculture, in which the conveyed fluid volume flow adapts itself to different operating modes. For improved self-priming, the rotary lobe pump is preferably designed for vertical mounting of the rotary lobes, wherein an angular gear is provided. The rotary lobes are mounted in a topside or underside cover, wherein the axes of the rotary lobes are vertically oriented. Using one of the covers, the rotary lobes can be vertically removed and maintained without having to dismantle other pump components from the pump housing. The rotary lobes can also be removed together with the angular gear as an integral pump component using one of the covers.