Abstract: A vacuum booster assembly includes, but is not limited to, a booster housing defining a booster chamber and including a gas inlet and a gas outlet; a first rotor positioned within the booster chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the booster chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10?6 in/in*K) to about 13 (10?6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the booster chamber includes a coating.

Abstract: A sealable volume has a wall forming at least a portion of a boundary limiting the volume. The wall includes a hydrogen permeation barrier including a layer system (LS) having at least one layer. The layer system includes at least one hydrogen barrier layer (HPBL) of an at least ternary oxide. Preferably, the oxide is substantially composed of Al, Cr and O and the hydrogen barrier layer (HPBL) is deposited using physical vapor deposition, in particular cathodic arc evaporation. Preferably, the layer system includes at least one of: an adhesion layer (AdhL), a hydrogen storage layer (HStL), a protective layer (ProtL), in particular a thermal barrier layer (ThBL), a diffusion barrier layer (DBL), an oxidation barrier layer (OxBL), a chemical barrier layer (ChBL), a wear resistance layer (WRL). Excellent hydrogen permeation barrier properties can be achieved, and the layer system can be tailored as required by an envisaged application.

Abstract: A housing for a rotary engine has: a peripheral wall defining two end faces and an inner face transverse to the two end faces; two side walls sealingly engaged to the two end faces of the peripheral wall, a core of a side wall of the two side walls having a core face, the core face having a cavity section facing the rotor cavity and an abutment section annularly extending around the cavity section, the abutment section facing an end face of the two end faces, the abutment section having a flared portion flaring away from the end face; and a coating on the core face, the coating made of a material harder than a material of the core of the side wall, the coating covering the cavity section and ending at a coating edge located on the flared portion, the coating edge free of contact with the end face.

Abstract: A threaded spindle machine includes a metal middle housing part (12) arranged between housing end caps (24) and forming a fluid chamber (16) for receiving a plurality of threaded spindles rotatably supported in the housing end caps (24); an insert (18) adhered into the middle housing part, which insert forms a wear-resistant running surface for the threaded spindles on the inner wall of the fluid chamber (16) and defines an adhesive gap (20) with the inner surface of the middle housing part (12); and at least one filling channel (26) leading from an outer surface of the middle housing part (12) to the adhesive gap (20), and the filling channel (26) extends from an end of the middle housing part (12) which is adjacent to a housing end cap (24).

Abstract: A rotary compressor includes: a closed upright cylindrical compressor housing including an upper portion provided with a discharge section of refrigerant and a body portion provided with an intake section of the refrigerant; a compression section disposed at a lower part in the compressor housing and configured to compress the refrigerant suctioned by the intake section to discharge the refrigerant from the discharge section; and a motor disposed at an upper part in the compressor housing and configured to drive the compression section. The motor has a rotor disposed on an inner side and a stator disposed on an outer side, the refrigerant is HFO1123 refrigerant or a refrigerant mixture containing the HFO1123 refrigerant, and an inner welded portion formed by welding using flux is provided within a projection area of the rotor at the upper portion of the compressor housing.

Abstract: An insulated seal seat assembly comprises a shaft configured and arranged to rotate about an axial axis, a seal seat that is secured to the shaft, and a thermal insulator configured and arranged radially between the shaft and the seal seat.

Abstract: An eccentric compensating torsional drive system for reducing the rotational eccentric conflict between multiple eccentric rotational movement limits on the eccentric offset within the drive system includes a motor, a first offset distance coupling, an offset floating bearing, and a dynamic element that is driven in a first offset distance rotation by the motor, coupling, and offset floating bearing. The dynamic element is pivotally connected to a static element via a pivotal offset bearing assembly having a substantially matching offset to the first offset distance. Operationally, the offset bearing can have relative rotational movement to the coupling and dynamic element to lessen the dynamic conflict as between the first offset distance and the pivotal offset bearing assembly, as the offset bearing acts as a floating variance in rotational offset via changing a radial position to the coupling and dynamic element.

Abstract: A rotary device has at least one seal arrangement between inner and outer components to constrain fluid flow there between. The seal arrangement has a smooth surface and an opposing surface with a plurality of grooves and lands along a length of the at least one seal with the lands are separated from the smooth surface by a predetermined gap. The grooves have a bottom surface substantially parallel to the smooth surface. The width of the lands is between about 125% to 145% of the width of the grooves. The groove depth is between about 30% to 50% of the width of the grooves. A corner radius between the bottom surface of the grooves and side walls of the grooves is between about 25% to 100% of the depth of the grooves.

Abstract: A rotary compressor includes a sealed vertical compressor housing, a compressing unit, and a motor. A refrigerant discharging unit is provided at an upper part and a refrigerant intake unit is provided at a lower part side surface in the sealed vertical compressor housing. The compressing unit is disposed on the lower part of the compressor housing, includes an annular cylinder, an end plate including a bearing unit and a discharge valve unit and blocking end portions of the cylinder, an annular piston that engages with an eccentric portion of a rotation axis supported by the bearing unit, revolves along a cylinder inner wall of the cylinder in the cylinder, and forms a cylinder chamber between the cylinder inner wall and the annular piston, and a vane. The motor is disposed on the upper part of the compressor housing, and drives the compressing unit via the rotation axis.

Abstract: A brake rotor assembly for use with an anti-lock braking system. The brake rotor assembly includes a brake rotor having a pair of braking surfaces; a tone ring having a first end having a plurality of spaced sensing formations disposed thereon and a second end for circumferentially contacting a surface of the brake rotor assembly, the first end thermally insulated from the brake rotor; and a snap ring for connecting the tone ring to the brake rotor assembly. A method of forming a brake rotor assembly is also provided.

Abstract: A pump having at least two fluid drivers and a method of delivering fluid from an inlet of the pump to an outlet of the pump using the at least two fluid drivers. Each of the fluid drives includes a prime mover and a fluid displacement member. The prime mover drives the fluid displacement member to transfer fluid. The fluid drivers are independently operated. However, the fluid drivers are operated such that contact between the fluid drivers is synchronized. That is, operation of the fluid drivers is synchronized such that the fluid displacement member in each fluid driver makes contact with another fluid displacement member. The contact can include at least one contact point, contact line, or contact area.

Abstract: A hydraulic tool includes a stator, a rotor, and a removable coating. At least one of the stator and the rotor comprises a resilient material. The removable coating has a thickness selected to compensate for expected swelling of the resilient material or an expected contraction of a clearance between the rotor and the stator based on thermal expansion. The removable coating is disposed on a surface of at least one of the rotor and the stator, and the removable coating is formulated to be removed during operation of the hydraulic tool. A method of operating a hydraulic tool includes passing a fluid through the hydraulic tool during rotation of the rotor within the stator and removing at least a portion of the removable coating responsive to rotation of the rotor within the stator as a volume of the resilient material increases responsive to contact with the fluid passing through the hydraulic fluid.

Abstract: A rotary internal combustion engine with a rotor body made at least in major part of a first material, including at least one land protruding axially from each of its end faces and defining a contact surface extending at a fixed position with respect to the end faces. The contact surface frictionally engages a portion of the inner surface of the internal cavity of the engine, and at least the outer surface of the land includes a second material. The second material has a greater wear resistance than that of the first material with respect to frictional engagement with the portion of the inner surface of the internal cavity contacting the land. A method of axially positioning a rotor of a rotary engine within an internal cavity of an outer body of the engine are also discussed.

Abstract: A hydraulic tool includes a stator and a rotor rotatably disposed within the stator. At least one of at least an inner portion of the stator and at least an outer portion of the rotor includes an insert comprising a hard material. A method of forming a hydraulic tool includes attaching at least one insert comprising a hard material to a surface of a stator or a surface of a rotor. A downhole motor or pump includes a stator and a rotor. The stator includes at least one insert comprising a hard material disposed over at least a portion of an interior surface thereof and a matrix material at least partially surrounding the at least one insert. The rotor includes at least one insert disposed over at least a portion of an exterior surface thereof and a matrix material at least partially surrounding the at least one insert.

Abstract: A disc brake assembly includes a rotor with an ABS tone ring insert assembly that functions as a rotation indicator in an anti-lock braking system. The insert is positioned in the hat of a rotor disc in a spaced relationship and is mounted to the mounting flange of the rotor disc. Forming the ring insert separately from the rotor disc also allows different coating materials to be used on the tone ring that may be more heat resistant. The ring insert assembly can be made of powder metal or made as a cast iron cylinder with a toothed cap made of powder metal having a corrosion resistant coating. Cost savings can be realized along with high performance when only a portion of the assembly if made of powder metal and coated.

Abstract: Designs for multiple segment lobe pumps are shown. The designs include pumps using rotors having two lobes to a plurality of lobes and segments that include two segments to a plurality of segments. Designs for both vertical, or straight walled conventional lobed rotors, as well as helical lobe rotors are shown. The designs are applicable to a variety of rotors and number of segments. In one particular case the designs enable a three lobe helical pump. Designs are also shown for separation plates used between the multiple segments. The separation float between the pairs of lobes in a segment and can also have a fixed position between the lobes by inclusion of end pieces that enable clamping of the separation plates in position.

Abstract: The invention relates to a rotary lobe pump for conveying a fluid medium containing solids, comprising an inlet and an outlet for the medium being conveyed, and further comprising a pump casing and two rotary lobes arranged in said pump casing and having intermeshing rotary lobe vanes. According to the invention, the pump casing has two opposite casing half-shells which seal the pump casing fluid-tightly. The casing half-shells are double-walled.

Abstract: A seal structure includes: first and second members defining a hollow internal area of a fluid device; and a seal member fixed to the first member for sealing a gap between the first and second members. The seal member includes a sliding contact member being in sliding contact with a surface of the second member and formed of a resin. The second member includes a resin layer and a resin layer holding structure. The resin layer is formed by sliding the second member on the sliding contact member to transfer the resin forming the sliding contact member onto a sliding contact portion of the surface of the second member at which the second member comes into contact with the sliding contact member. The resin layer holding structure is a porous film formed by electric discharge surface treatment and holds the resin layer in the sliding contact portion.

Abstract: A gear ring pump includes a pump bearing arranged in the housing cover. A port support is mounted in the pump housing between the impeller set and the end wall of the working chamber in a movable manner towards the driveshaft such that the port support is prevented from rotating. The port support has a suction kidney and a pressure kidney which pass through the port support separately from each other across the entire width of the port support. The thickness of the port support approximately matches the thickness of the impeller set but can also project past the thickness of the impeller set by up to 20%. The thermal expansion coefficient of the port support is approximately 70% to 120% greater than the thermal expansion coefficient of the pump housing. The driveshaft which is rotationally fixed to the inner rotor does not protrude into the port support.

Abstract: A compressor includes a compression mechanism and a resin layer including a stack of three or more layers formed on a whole area or a portion of at least one surface of at least one part of the compression mechanism. A hardness of a layer most distant from a base in the resin layer is smaller than a hardness of a layer closest to the base in the resin layer. A difference in hardness between two adjacent layers in the resin layer is smaller than a difference in hardness between the layer most distant from the base and the layer closest to the base.

Abstract: The invention relates to a gear pump (1) for conveying a fluid, said gear pump comprising a rotatably mounted, external geared toothed wheel (3) and an internal geared annular gear (2) that are meshed in order to generate a conveying action, and are arranged together with an electrically commutable stator (7) in a housing (5). The stator (7) extends concentrically around the annular gear (2) and interacts with the annular gear to generate an electromotive force. The annular gear (2) has a closed, homogeneous cylindrical surface and a plain bearing (13) is provided on the stator (7).

Abstract: An apparatus for use in a wellbore may include a stator having a bore and a rotor disposed in the bore. Either or both of the rotor and the stator may include a layer that has an asymmetrical material property profile along at least a portion of a circumference of that layer.

Abstract: Methods of removing moisture from a compressor using a sorbent technology are provided. A dehydration device incorporating the sorbent technology is disposed in a system that contains a hygroscopic fluid. By passing the hygroscopic fluid over the sorbent technology, moisture is removed from the hygroscopic fluid. The systems include sealed devices and integral components for heating, ventilation, and air conditioning (HVAC) systems and refrigeration devices.

Abstract: A compressor, characterized in that a steel is used as the base material for the other sliding material vane 10 and nitrided, a CrN or DLC film is formed on the surface by PVD treatment, and a Ni—Cr—Mo cast iron is used for the other corresponding sliding material piston 9. It is possible in such a configuration to suppress the temperature rise by sliding friction of the sliding materials, such as the vane tip region 10a and the peripheral region of piston 9 that are vigorously slid, relax decomposition of the refrigerant, and suppress corrosion by hydrogen fluoride generated in reaction with water and oxygen, and thus to provide a compressor higher in reliability.

Abstract: A refrigerant compressor includes a compression unit having a roller and a vane for compressing refrigerant. The vane has a film having first to fourth layers on its metallic base member. The first layer is made of chromium. The second layer is made of chromium and tungsten-carbide. The third layer is made of metal-containing amorphous-carbon containing at least tungsten or tungsten-carbide. The fourth layer is made of non-metal-containing amorphous-carbon containing carbon and hydrogen. In the second layer, chromium content-rate on a first-layer side is larger than on a third-layer side, and tungsten-carbide content-rate on the third-layer side is larger than on the first-layer side. In the third layer, content-rate of the at least tungsten or tungsten-carbide on a second-layer side is larger than on a fourth-layer side. The roller with which an end-edge of the vane slidably-contacts is made of flake graphite cast iron containing molybdenum, nickel and chromium.

Abstract: A fluid pump includes a motor, an inner gear rotor and an outer gear rotor. The inner gear rotor is driven for rotation about an axis by the motor and has a plurality of outwardly extending teeth. The outer gear rotor has a plurality of inwardly extending teeth that are engaged by the teeth of the inner gear rotor so that the outer gear rotor is driven for rotation about a second axis when the inner gear rotor rotates. At least one of the inner gear rotor and the outer gear rotor is formed from a plastic material.

Abstract: According to one embodiment of the invention, a gerotor apparatus includes an outer gerotor having an outer gerotor chamber, an inner gerotor, at least a portion of which is disposed within the outer gerotor chamber, and a synchronizing apparatus operable to control the rotation of the inner gerotor relative to the outer gerotor. The inner gerotor includes one or more entrance passages operable to communicate a lubricant into the outer gerotor chamber.

Abstract: In order to prevent deterioration in performance of an oil-free screw compressor and scuffing caused by rust, surfaces of both male and female rotors are coated with heat-resistance coatings containing a solid lubricant. A coating contains Polyimide resin to which Molybdenum disulfide, as a solid lubricant, and Aluminum oxide and Titanium oxide, as additives, are added. Accordingly, it is possible to realize a coating that is higher in heat resistance and longer in lifetime than a conventional one.

Abstract: A screw spindle machine having a tubular casing (10) that is made of cast metal and is lined with a wear resistant layer (16), with the wear resistant layer (16) being encapsulated in a steel shell (20) that matches the outer peripheral shape of the layer (16).

Abstract: A rotary pump having a variable delivery volume, including: 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 use in producing a stator for a progressing cavity apparatus which includes the use of electroforming to produce the stator tube. A stator tube for a progressing cavity apparatus which is produced using electroforming and a stator for a progressing cavity apparatus which includes a stator tube produced using electroforming.

Abstract: A scroll compressor is constructed by combining a stationary scroll and an orbiting scroll formed by erecting a scroll-shape wrap upright on a base plate meshing with each other. A scroll member constructing the stationary scroll or the orbiting scroll is constructed of an inner layer member 601 forming a core metal and an outer layer member 600 arranged so as to surround the inner layer member and forming an outer layer part, the inner layer member is constructed of a material with higher modulus of elasticity than that of the outer layer member, and separation prevention parts (uneven parts 603, depressions 604, or holes 605) preventing the inner layer member and the outer layer member from separating with each other due to difference in coefficient of thermal expansion thereof are arranged in the inner layer member.

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: A method for manufacturing roller pockets in a stator of a gerotor device generally includes providing a stator having a cavity including a generally cylindrical section defining a central axis and a plurality of roller pockets angularly spaced around a periphery of the cylindrical section. Each roller pocket is configured to receive a respective roller, which acts as an internal tooth of the gerotor device. Each roller pocket defines a generally cylindrical roller pocket bearing surface. The method further includes grinding each roller pocket bearing surface of each roller pocket with a grinding wheel rotating about a rotational axis perpendicular to the central axis. A stator for a gerotor device is also described.

Abstract: A progressing cavity pump/motor (10) includes a stator housing (12), a polymeric layer (14), and a rotor (16). A plurality of axially extending grooves (24) are formed in the interior surface of the stator housing for receiving polymeric material therein. At least one seal gland (46) adjacent an end of the polymeric layer maintains sealing between the stator housing and the polymeric layer.

Abstract: A method for use in producing a stator for a progressing cavity apparatus which includes the use of electroforming to produce the stator tube. A stator tube for a progressing cavity apparatus which is produced using electroforming and a stator for a progressing cavity apparatus which includes a stator tube produced using electroforming.

Abstract: A scroll fluid machine that is capable of preventing a power loss and enhancing the degree of hermeticity of compression chambers. A plurality of outer peripheral projections are formed on an outer peripheral surface of a wrap portion of each scroll. An outer peripheral coating layer is formed on an outer peripheral surface of a wrap portion of a fixed scroll, and an inner peripheral coating layer is formed on an inner peripheral surface of the wrap portion. Each of the coating layers comprises: contact portions that make contact with the mating wrap portion; and non-contact portions that do not make contact with the mating wrap portion. In this way, the degree of hermeticity of the compression chambers can be enhanced by the contact portions, and power loss can be prevented by the non-contact portions.

Abstract: A refrigerant compressor includes a first layer (24) composed of a single layer of chromium, a second layer (25) composed of an alloy layer of chromium and tungsten carbide, a third layer (26) composed of an amorphous carbon layer containing at least one of tungsten and tungsten carbide, and a fourth layer (27) composed of an amorphous carbon layer containing carbon and hydrogen without metals, which are sequentially formed on a surface of a sliding member (13b) of a compression mechanism formed of tool steel. The second layer (25) is formed to have a chromium content higher on a side of the first layer (24) than a side of the third layer (26), and have a tungsten carbide content higher on the side of the third layer (26) than the side of the first layer (24). In addition, the third layer (26) is formed to have a tungsten content or a tungsten carbide content higher on a side of the second layer (25) than a side of the fourth layer (27).

Abstract: Scrolls made from one or more near-net shaped powder metal processes either wholly or fabricated together from sections. Both “conventional” press and sinter methods and metal injection molding methods will be described.

Abstract: A high capacity lightweight compact vane motor or pump system which utilizes vanes with extensions to improve efficiency of the system overall. The present invention generally includes a rotor housing, a rotor, a housing cover. The rotor housing will generally include a central opening in which the rotor is positioned. The rotor will generally include a plurality of radially spaced vane slots. A rotor vane will generally be positioned within each vane slot. Each rotor vane will generally include a first extension and a second extension, wherein the first extension extends into slidable engagement with a groove on the housing cover and the second extension extends into slidable engagement with a groove on the interior surface of the rotor housing. As the rotor is rotated within the housing, the vanes will slide into and out of the slots to create voids to hold oil to be expelled at the outlet.

Abstract: A single screw compressor structure includes a screw rotor and a casing, which houses the screw rotor. A tapered outer circumferential surface of the screw rotor has a plurality of helical grooves, with an outer diameter that increases from an inlet side toward a discharge side. The casing includes an outer tube member having a circular inner hole to form an interior, and an inner tube member is fixed to the interior of the outer tube member. The inner tube member has a tapered inner surface that opposes the tapered outer circumferential surface of the screw rotor. A single screw compressor further including a gate rotor is assembled by adjusting mesh between the screw rotor and the gate rotor, aligning the tapered outer and inner circumferential surfaces relative to one another, and integrally coupling the outer and inner tube members to each other.

Abstract: The invention relates to a vane for a vane pump, in particular a vane vacuum pump, having a crucible-shaped housing and provided with a rotor mounted eccentrically and rotatably in the housing, wherein the vane is displaceably mounted perpendicular to the axis of rotation in the rotor and the free ends thereof are in contact with the interior circumferential surface of the housing, wherein the vane has a closed surface, at least in the sections protruding beyond the rotor, in the direction of the interior circumferential surface, and the surface is formed by an exterior wall, which is provided with a coating, wherein the coating is provided with perforations in the area located inside the rotor.

Abstract: The invention pertains to a dry vacuum pump comprising at least one rotating shaft (11) mounted on at least one lubricated bearing (5) and at least one sealing device (9) for sealing off lubricating fluids capable of entering the shaft passage from said bearing (5), said sealing device (9) being installed between the lubricated bearing (5) and a dry pumping stage (7), characterized in that said sealing device (9) comprises a centrifuge element (17) designed to rotate in unison on said shaft (11) and comprising at least one through line (19) capable of separating the lubricating fluids from the fluid that may travel from said bearing (5) to the dry pumping stage (7).

Abstract: A stator for a progressive cavity pump or motor comprises a tubular housing having a central axis. In addition, the stator comprises a stator insert coaxially disposed within the housing. The stator insert has a radially outer surface that engages the housing and a radially inner surface defining a helical-shaped through bore extending axially through the stator insert. The stator insert includes an insert body and an insert liner attached to the insert body. The insert body is radially positioned between the housing and the insert liner. The insert body comprises a reinforcement structure and a plurality of voids dispersed within the reinforcement structure.

Abstract: An insulated glass secondary edge sealing device that dispenses sealant to insulated glass units including at least two panes of glass separated by a spacer, including a fixed sealant dispensing head, a table that supports the insulated glass units, a fence, a depth sensor, a linear motion encoder, a metering device. The sealant dispensing head has a dispensing nozzle and a corner dam. The dispensing nozzle includes a floating insulated glass unit contact surface and the corner dam is shiftable between a retracted position and an extended position. A control unit receives signals from the depth sensor and the linear motion encoder and controls the metering device to dispense a measured flow of sealant based on the depth of the inset of the spacer and the movement of the insulated glass unit parallel to the fence and relative to the encoder.

Abstract: A compressor slider has a carbon content of 2.0 wt % to 2.7 wt %, a silicon content of 1.0 wt % to 3.0 wt %, a balance of iron that includes unavoidable impurities, graphite that is smaller than the flake graphite of flake graphite cast iron, and a hardness that is greater than HRB 90 but less than HRB 100 in at least a portion of the slider.

Abstract: In aspects, the disclosure provides a drilling motor that includes a stator and a rotor disposed in the stator, wherein the inner surface of the stator and/or outer surface of the stator includes a coating of a diamond-like carbon material.

Abstract: A scroll type compressor includes a fixed scroll having a suction opening, a movable scroll, a hermetically sealed container having an upper cap, and a suction pipe that penetrates through the upper cap and is engagedly fitted through an O ring in the suction opening of the fixed scroll at a lower portion thereof. The upper cap includes a pipe stand formed of iron at a suction-pipe penetrating portion thereof. The suction pipe comprises an iron lower suction member that is engagedly fitted in the suction opening of the fixed scroll and an O-ring groove in which the O ring is fitted, and a copper upper suction member that is joined to the lower suction member by brazing and engagedly fitted in the pipe stand. The upper suction member and the pipe stand are joined to each other by brazing.

Abstract: A skinned rotor 201 or skinned stator 305 of a progressive cavity apparatus is described. A rotor 201 can be skinned by threading a sleeve 210 with a profiled helical outer 212 and profiled helical inner 214 surface onto a core 202 with a profiled helical outer surface 204. A rotor (1301, 1401) can also be skinned by inserting a non-helical core (1302, 1402) into a non-helical longitudinal bore (1314, 1414) of a sleeve (1310, 1410) with a profiled helical outer surface (1312, 1412). A stator 305 can be skinned by threading a tubular liner 310 with profiled helical inner 314 and profiled helical outer 312 surfaces into a profiled helical bore 308 of a tube 306. A stator (2405, 2505) can also be skinned by inserting a tubular liner (2410, 2510) with a non-helical outer surface (2412, 2512) into a non-helical bore (2408, 2508) of a tube (2406, 2506).

Abstract: A high performance gear type oil pump for an internal combustion engine which has drive and driven gears which are, on one common side of the gears, respectively supported from the housing by a drive shaft and an idler shaft. In order to avoid cantilevering of the gears when generating pressurized oil, the other common side of the gears are each rotatable mounted on stub axles or pins which themselves are fixedly attached to the housing. In order to minimize wear, oil under pressure is supplied to the bearing surfaces of stub axles or pins which extend interiorly of the gears and also to the bearing surfaces of the housing which faces the common side of the gears where the stub axles are located, through oil supply passageways in the stub axles or pins.