Abstract: A dry rotary pump for recirculating an at least partially gaseous composition containing hydrogen. The dry rotary pump comprising a first rotating shaft and a second rotating shaft. The first rotating shaft and the second rotating shaft are driven in rotation by a drive system in a gear chamber. The dry rotary pump comprises a first pair of seals and a second pair of seals, each comprising a first shaft seal and a second shaft seal. The dry rotary pump comprises a pressure equalization chamber in fluid connection with a gap between the first shaft seal and the second shaft seal to regulate pressure in the gap. The gear chamber is in fluid connection with the gap, and the pumping chamber is in fluid connection with the first shaft seal and the first shaft seal by a pulsation attenuation chamber.

Abstract: A gear pump is provided with: a casing including a suction port configured to suck fluid, and a discharge port configured to expel the pressurized fluid; a gear including a wheel portion with gear teeth and an axially elongated shaft portion, the gear being so housed in the casing as to transport the fluid from the suction port to the discharge port; and a floating bearing rotatably supporting the shaft portion and being movable axially, the floating bearing including a sealing face in contact with the wheel portion, a receiver face axially opposed to the sealing face; and a communication path having an opening on the sealing face and communicating the opening with a third pressurization chamber defined by a third receiver face of the receiver face and the casing.

Abstract: An actuator for a compressor element, the actuator comprising an electrical motor with a motor casing which defines a motor chamber in which a motor rotor is positioned rotatably with the help of one or more motor bearings in relation to a motor stator, whereby the motor stator is built of laminations around which windings are attached and whereby the motor rotor is built of a shaft with laminations, whereby the actuator is further equipped with a cooling circuit for a coolant, wherein the coolant is water, the motor bearings are water-lubricated, the shaft on the motor rotor is made from stainless steel, the windings are embedded in an epoxy resin and a composite sleeve is applied around each of the laminations on the motor rotor and on the motor stator.

Abstract: One or more techniques and/or systems are disclosed for a pump technology that provides for more effective and efficient transfer of liquids, such as petroleum products and components, to and through pipelines. Such a technology can comprise a type of external gear pump that creates higher flow, resulting in higher pressures in the pipeline, to move the liquids, while providing for longer pump life, simpler and less maintenance, and fewer undesired conditions, with a smaller footprint, in a cost-effective system.

Abstract: A rotary pump with a rotational direction which can be switched, including: a housing which has a pump space featuring an inlet into a low-pressure region of the pump space for a medium to be pumped and an outlet out of a high-pressure region of the pump space for the medium to be pumped; at least one rotor; at least one bearing for the at least one rotor; at least one sealing stay which axially faces the rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the rotor; and a lubricant feed which feeds a lubricant from the pump space to at least the bearing, wherein the lubricant feed is formed in the sealing stay.

Abstract: To reduce frictional heat generated between a rotation shaft and a bearing portion in a gear pump in which the rotation shaft having a gear mounted thereon is received by the bearing portion and an image recording apparatus having the gear pump. Provided is a gear pump which has a rotation shaft, a bearing portion which receives the rotation shaft, and a gear which is mounted on the rotation shaft and rotates with the rotation shaft, in such a manner that the gear feeds liquid. Furthermore, at least either a concave portion or a convex portion is provided in at least either the rotation shaft or the bearing portion.

Abstract: A sectional sealing system for water-spray type screw rotor compressor that is configured to prevent the intermixing of coolant and working fluid from a compression chamber with lubricant used to lubricate at least a bearing system of a rotor. The sealing system may include suction side and discharge side sealing portions that are positioned about first and second shafts, respectively, of the rotor. The suction side sealing portion may include a first seal, a first labyrinth seal, and a second labyrinth seal, the first seal being in proximity to a suction side of the compression chamber. The discharge side sealing portion may include a plurality of first seals, a second seal, a first labyrinth seal, and a second labyrinth seal, the plurality of first seals of the discharge side sealing portion being in proximity to a discharge side of the compression chamber.

Abstract: A system and method are presented for improved performance of gerotor compressors and expanders. Certain aspects of the disclosure reduce porting losses in a gerotor system. Other aspects of the disclosure provide for reduced deflection in lobes of an outer rotor of a gerotor system. Still other aspects of the disclosure provide for reduced leakage through tight gaps between components of a gerotor system.

Abstract: A gear pump includes a pair of gears that meshes with each other, two rotational shafts inserted into the respective gears that rotate together with gears, a pair of side plates arranged adjacent to both side surfaces of the gears, each having two through-holes forming bearings of the two shafts, a seal block that abuts against the pair of side plates and covers a part of the pair of gears, a pump assembly having the gears, the two shafts, the pair of side plates, and the seal block, and a case having a recess to accommodate the pump assembly. A line passing through an arc center of a cylindrical surface inscribed in the facing surface of the case, and parallel to the two shafts, forms a rotating axis. When the pump assembly rotates about the rotating axis, one of the of side plates contacts the inner wall of the case.

Abstract: One embodiment includes a gear pump with a driven gear, a gear shaft passing through the driven gear, and a pressure loaded journal bearing. Also included is a fluid film, between a surface of the pressure loaded journal bearing and a surface of the gear shaft, and a hybrid pad on the pressure loaded journal bearing. The hybrid pad has a minimum leading edge angular location on the pressure loaded journal bearing of 41.5° and a maximum trailing edge angular location on the pressure loaded journal bearing of 54.5°. The gear pump also includes a porting path for supplying high pressure fluid from a discharge of the gear pump to the fluid film at the hybrid pad.

Abstract: One embodiment includes a gear pump with a driven gear, a gear shaft passing through the driven gear, and a stationary journal bearing. Also included is a fluid film, between a surface of the stationary journal bearing and a surface of the gear shaft, and a hybrid pad on the stationary journal bearing. The hybrid pad has a minimum leading edge angular location on the stationary journal bearing of 41.5° and a maximum trailing edge angular location on the stationary journal bearing of 54.5°. The gear pump also includes a porting path for supplying high pressure fluid from a discharge of the gear pump to the fluid film at the hybrid pad.

Abstract: One embodiment includes a gear pump with a drive gear, a gear shaft passing through the drive gear, and a stationary journal bearing. Also included is a fluid film, between a surface of the stationary journal bearing and a surface of the gear shaft, and a hybrid pad on the stationary journal bearing. The hybrid pad has a minimum leading edge angular location on the stationary journal bearing of 29.5° and a maximum trailing edge angular location on the stationary journal bearing of 42.5°. The gear pump also includes a porting path for supplying high pressure fluid from a discharge of the gear pump to the fluid film at the hybrid pad.

Abstract: One embodiment includes a gear pump with a drive gear, a gear shaft passing through the drive gear, and a pressure loaded journal bearing. Also included is a fluid film, between a surface of the pressure loaded journal bearing and a surface of the gear shaft, and a hybrid pad on the pressure loaded journal bearing. The hybrid pad has a minimum leading edge angular location on the pressure loaded journal bearing of 29.5° and a maximum trailing edge angular location on the pressure loaded journal bearing of 42.5°. The gear pump also includes a porting path for supplying high pressure fluid from a discharge of the gear pump to the fluid film at the hybrid pad.

Abstract: A rotary pump can pump a liquid for pollution control of exhaust gases in a system on board a vehicle and can include a rotor and a stator that are positioned in a casing. The casing can include a wall delimiting a main internal volume and an integral outlet pipe for the pump. A pressure sensor can be positioned within the main internal volume of the casing.

Abstract: The invention relates to a double-flow screw spindle machine for drive generation by multiphase mixtures or for the delivery of multiphase mixtures, comprising at least two separate inlet chambers (11, 12) and an outlet chamber (20), and a separator (30), situated upstream of the inlet chambers (11, 12), for separating liquid phase and gas phase. The object of the present invention is to provide a dual-flow screw spindle machine which is easily adaptable to changed process conditions. This object is achieved by virtue of the fact that both inlet chambers (11, 12) are connected to the separator (30) by separate lines (31, 32; 33) for the gas phase and the liquid phase.

Abstract: A spindle motor includes a shaft extending in an axial direction, and a base portion configured to define a portion of a housing, and including a through hole in which the shaft is inserted. The shaft includes a non-through hole portion, a first connection channel, and a second connection channel extending from the non-through hole portion in a radial direction. An upper portion of the hole portion includes a screw hole portion including a screw thread. A minimum diameter of the screw thread is greater than an inside diameter of the hole portion. A sealing member is located between the screw hole portion and the first connection channel.

Abstract: An input shaft assembly is movable along an axis to absorb external impact loads. A biasing member exerts an axial load in a direction counter to potential impact loads. A stop is provided to control the application of biasing loads to control application of such axial load.

Abstract: Multistage pump comprising a plurality of components which include a plurality of pre-assembled pump modules, having at least one twin screw pump module. The multistage pump further has an elongate sleeve for housing the components, and a securing device attachable or engagable with a portion of the elongate sleeve. The securing device is operable to fixedly retain the components within the sleeve. Each of the pre-assembled pump modules has at least one thrust bearing.

Abstract: A metering pump or segment, and a metering pump assembly comprising a plurality of the metering pumps or segments, are disclosed. The drive shaft assembly for driving the pump gears of each metering pump or segment is coaxially aligned with the longitudinal axis of the pump or segment, as is the fluid inlet. The single drive shaft assembly is utilized to drive all of the metering pumps or segments comprising the metering pump assembly, and the different metering pumps or segments are fluidically connected together by means of a common fluid passageway. In addition, the different metering pumps or segments can be interchanged or exchanged so as to permit different metered fluid output volumes to be outputted at different predetermined locations, and the dispensing volumes can also be added together.

Abstract: A vacuum pump includes a pumping stage, a rotary shaft supported by a lubricated support bearing; a lubricant deflector mounted between the lubricated support bearing and a ring seal which is mounted on the rotary shaft between the lubricant deflector and the pumping stage, a first reservoir containing a first reserve of liquid lubricant and in communication with the lubricated support bearing in a first volume, a lubricant splashing unit mounted on the rotary shaft in the first reservoir and having one end bathed in the first reserve of lubricant. A second reservoir includes a second reserve of liquid lubricant separated from the first reservoir by a separation wall having an aperture through which the first and second reserves of lubricant communicate. A lubricant return channel having one inlet facing the lubricant deflector opens into the second volume of the second reservoir above the second reserve of lubricant.

Abstract: A pump or motor for fluid or gaseous media comprising a shaft (4), which faces a working part (13) and has a common inclined sliding surface (14) with the same, whereby the working part (13) limiting the pump working spaces (12) wobbles in a positionally fixed housing (10).

Abstract: A coupling shaft assembly includes a coupling shaft with a first radial shoulder and a second radial shoulder, the first radial shoulder and the second radial shoulder each include at least one slot to provide a lubricant flow path.

Abstract: A screw fluid machine has a first non-contact seal, a second non-contact seal and a lip seal disposed between a rotor chamber and a bearing for a rotor shaft located on the high pressure side, and in this order from the rotor chamber side. It includes a pressurized communicating channel for introducing high-pressure target gas into a pressurized space formed between the first and second non-contact seals, a pressurized pressure detecting device for detecting the pressure of the pressurized space, and an alarm device for generating an alarm when a value detected by the pressurized pressure detecting device falls out of a predefined range of pressurized pressures. The screw fluid machine is capable of detecting or predicting a condition of the shaft sealing device and accurately and reliably reporting the detected condition to an operator.

Abstract: A water-lubrication type screw fluid machine has a first non-contact seal, a second non-contact seal and a lip seal disposed between a rotor chamber and a bearing for a rotor shaft. The bearing is located on the high pressure side and in this order from the rotor chamber side. the bearing includes a low pressure communicating channel for allowing an outflow space formed on the rotor chamber side with respect to the first non-contact seal to communicate with a low pressure channel for the target gas communicating with a low pressure space inside the rotor chamber or the rotor chamber, a pressurized communicating channel for introducing high-pressure target gas into a pressurized space formed between the first and second non-contact seals, and an open communicating channel through which an open space formed between the second non-contact seal and the lip seal opens to the outside of the casing.

Abstract: A lubricant metering system for a compressor may include a cap, a cap cage, and a shaft. The cap may include an outer surface, a first recess, and a first radial bore extending between the first recess and the outer surface. The cap cage may include a second recess receiving the cap and a lubricant inlet in communication with the first recess via the first radial bore. The shaft may be received within the first recess and may include an axially extending bore and a second radial bore extending between an outer diameter of the shaft and the axially extending bore. The shaft may be mounted for rotation relative to the cap to allow lubricant to flow into the axially extending bore via the first and second radial bores when the second radial bore is aligned with the first radial bore.

Abstract: A bidirectional sealless ink pumping system used in an inkjet printing device includes a liquid ink reservoir and a pump. The pump moves ink from the reservoir through a pumping chamber to supply ink to printheads in the printer, and moves ink from a recirculation receptacle through the pumping chamber to the reservoir. A portion of the ink in the pumping chamber is drawn out of the pumping chamber to lubricate the moving member and is filtered before returning to the pumping chamber.

Abstract: In a pump system, a process fluid is directed into inlet chambers of a pump casing at an inlet pressure, and a plurality of rotors disposed inside the pump casing are rotated to pump the process fluid from the inlet chambers to an outlet chamber located between the inlet chambers, wherein the process fluid in the outlet chambers is at an outlet pressure. The process fluid is directed from the outlet chamber to a separator configured to separate particulate matter from the process fluid, and a portion of separated process fluid is directed from the separator to a gear chamber of the pump. Pump bearings are lubricated with the portion of separated process fluid from the gear chamber. Some of the portion of the separated process fluid from the pump bearing is leaked to the inlet chambers via rotor shrouds to reduce accumulation of particulate matter in the inlet chambers.

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.

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: In a motor-driven scroll type compressor, a rotary shaft includes a first opening at a position adjacent to a front end of the rotary shaft and facing an inner surface of a bearing for rotatably supporting the front end of the rotary shaft, a second opening at a position adjacent to a rear end of the rotary shaft and communicating with a back pressure chamber provided in front of a movable scroll member in a housing of the compressor, a communication passage interconnecting the first opening and the second opening, and a throttle formed by a clearance between the first opening and the inner surface of the bearing.

Abstract: Rotor having a shaft having an axial direction, where an inner and central cooling channel with an inlet and an outlet for a cooling agent is provided in this shaft, extending in the above-mentioned axial direction. Additionally, the above-mentioned cooling channel is at least partly provided with inwardly directed fins.

Abstract: The expander-compressor unit 70 includes the closed casing 1, the expansion mechanism 4 disposed in the closed casing 1 so that a surrounding space thereof is filled with the oil, the compression mechanism 2 disposed in the closed casing 1 so as to be positioned higher than the oil level, the shaft 5 for coupling the compression mechanism and the expansion mechanism 4 to each other, and the oil flow suppressing member 50 disposed in the surrounding space of the expansion mechanism 4 so that the space 55a filled with the oil is formed between the expansion mechanism 4 and the oil flow suppressing member 50. Thereby the flow of the oil filling the inner reserving space 55a is suppressed, and thus, heat transfer from the high temperature oil to the low temperature expansion mechanism can be reduced.

Abstract: An expander-integrated compressor (5A) has a compression mechanism (21) for compressing a refrigerant and an expansion mechanism (22) for expanding the refrigerant. The compression mechanism (21) is located above the expansion mechanism (22) inside a closed casing (10) and shares a rotating shaft (36) with the expansion mechanism (22). An oil pump (37) is provided at the lower end of the rotating shaft (36). The oil pump (37) is immersed in oil in an oil reservoir (15). Usually, the oil is placed in the oil reservoir (15) in such a manner that the oil level (OL) is located above a lower end portion (34e) of a vane (34a) of a first expansion section (30a). More preferably, the oil is placed in such a manner that the expansion mechanism (22) is immersed in the oil. An oil supply passage (38) for guiding the oil to the compression mechanism (21) is formed inside the rotating shaft (36). A suction port (37a) of the oil pump (37) is provided below the lower end portion (34e) of the vane (34a).

Abstract: Gearwheel pump, having a housing with at least two intermeshing gears with shafts supported by slide bearings lubricated with pumping medium (M) fed from a suction side to a pressure side, a return duct which leads pumping medium which flows outward through the plain bearing back to the suction side, and a valve (5) having a stationary part and a moveable part (20, 21). The valve (5) has a setting characteristic which runs, as a first approximation, linearly at least in one region, wherein the setting characteristic is defined by a differential pressure (?p) across the valve as a function of a setting path (x) in the valve (5) thereby significantly improving capability for setting the pressure in the transition region between the plain bearing and a dynamic seal of a driveshaft which is guided outward.

Abstract: A shaft assembly includes a fluid transfer insert located within a bore of a shaft. The fluid transfer insert seals to the shaft and includes at least one fluid channel that communicates between a plurality of fluid ports located in the shaft. The fluid channel is defined by an outer surface of the fluid transfer insert.

Abstract: A compressor (20) has an unloading slide valve (100). The valve has a valve element (102) having a range between a first condition and a second condition, the second condition being unloaded relative to the first condition. A first surface (200) of the valve element (102) is in sliding engagement with a second surface (202) of the housing (22) during movement between the first and second conditions. The valve element is coupled to an actuating piston (124). The compressor includes a linear bearing (132) guiding a piston shaft (122).

Abstract: A fuel pump is disclosed, especially a prefeed pump for feeding aircraft fuel to the high pressure pump, wherein the form-fit connection between the drive shaft (4) and the driven impeller (2) is produced by a regular, convex, triangular polygonal contour having rounded-off lateral faces and corner faces, the drive shaft and the impeller being provided with the polygonal contour. In this manner, the wear resulting from the poor lubricating power of the kerosene-based aircraft fuel can be reduced and the service life of the fuel pump can be increased.

Abstract: A rotor assembly for a supercharger assembly is provided. The rotor assembly includes at least one lobe defining at least one cavity. The at least one cavity is configured to contain a fluid operable to cool the at least one lobe. A supercharger incorporating the rotor assembly is also disclosed.

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: In a pump system, a process fluid is directed into inlet chambers of a pump casing at an inlet pressure, and a plurality of rotors disposed inside the pump casing are rotated to pump the process fluid from the inlet chambers to an outlet chamber located between the inlet chambers, wherein the process fluid in the outlet chambers is at an outlet pressure. The process fluid is directed from the outlet chamber to a separator configured to separate particulate matter from the process fluid, and a portion of separated process fluid is directed from the separator to a gear chamber of the pump. Pump bearings are lubricated with the portion of separated process fluid from the gear chamber. Some of the portion of the separated process fluid from the pump bearing is leaked to the inlet chambers via rotor shrouds to reduce accumulation of particulate matter in the inlet chambers.

Abstract: An expander-compressor unit (200) includes a closed casing (1), a compression mechanism (2) disposed at an upper position in the closed casing (1), an expansion mechanism (3) disposed at a lower position in the closed casing (1), a shaft (5) coupling the compression mechanism (2) to the expansion mechanism (3), and an oil pump (6) disposed between the compression mechanism (2) and the expansion mechanism (3). The oil pump (6) supplies the oil held in an oil reservoir (25) to the compression mechanism (2) via a suction passage. A strainer (65) is provided to the suction passage so that the oil to be drawn into the oil pump (6) passes through the strainer.

Abstract: To provide a rotor apparatus of a pump in which pressure release in the air gap between an oil seal and an inner rotor is conducted smoothly and good durability and sealing ability of the oil seal is maintained and which has a very simple structure and allows the increase in size to be avoided. The rotor apparatus of a pump includes a drive shaft in which a plurality of arcuate circumferential surface sections centering on an axial center and a plurality of flat surface sections are disposed alternately, and an inner rotor having a mounting hole into which the drive shaft is inserted. In the mounting hole, arcuate inner peripheral sections corresponding and equal in number to the arcuate circumferential surface sections and flat surface inner peripheral sections corresponding and equal in number to the flat surface sections are formed alternately.

Abstract: An intended purpose of this invention is to realize a gear pump suitable for delivery of high-pressure and high-viscosity fluids by using helical gears 2 and 3 meshing with each other. For this purpose, the gear pump includes introduction paths 121 and 131 for introducing the fluid from a discharge side toward shaft end sides of gear shafts 21 and 31 to apply shaft ends of the gear shafts 21 and 31 with fluid pressures counterbalancing axial thrusts produced by the helical gears 2 and 3.

Abstract: In a hermetically sealed compressor 100 including a rotary compressing element (4) having at least one cylinder (43A, 43B), and a roller (45) provided to the cylinder so as to be freely eccentrically rotatable, an electrically-driven element (2) for driving the roller (45) and a hermetically sealed container in which the rotary compressing element and the electrically-driven element are accommodated, oil (8) being stocked in the hermetically sealed container (1), the oil (8) in the hermetically sealed container (1) is injected into the compression chamber (43) when refrigerant is sucked into the compression chamber (43) of the cylinder.

Abstract: In a compression/expansion unit (30) serving as a fluid machine, both a compression mechanism (50) and an expansion mechanism (60) are housed in a single casing (31). An oil supply passageway (90) is formed in a shaft (40) by which the compression mechanism (50) and the expansion mechanism (60) are coupled together. Refrigeration oil accumulated in the bottom of the casing (31) is drawn up into the oil supply passageway (90) and is supplied to the compression mechanism (50) and to the expansion mechanism (60). Surplus refrigeration oil, which is supplied to neither of the compression and expansion mechanisms (50) and (60), is discharged out of the terminating end of the oil supply passageway (90) which opens at the upper end of the shaft (40). Thereafter, the surplus refrigeration oil flows into an oil return pipe (102) from a lead-out hole (101) and is returned back towards a second space (39).

Abstract: An improved pump and pumping method includes a circumferential positive displacement pump having two counter rotating rotors. A clearance gap is defined between the rotor shaft, and a body hub portion of the body that forms the chamber.

Abstract: A shaft assembly includes a fluid transfer insert located within a bore of a shaft. The fluid transfer insert seals to the shaft and includes at least one fluid channel that communicates between a plurality of fluid ports located in the shaft. The fluid channel is defined by an outer surface of the fluid transfer insert.

Abstract: A rotary fluid pressure device (11) has a stationary valve member (17), a rotatable valve member (51), and a valve seating mechanism (73). The valve seating mechanism (73) defines an outer balance ring member (75) having a valve-confronting surface (79) in engagement with an opposite surface (81) of the rotatable valve member (51) and an inner balance ring member (77) having a valve-confronting surface (111) in engagement with the opposite surface (81) of the rotatable valve member (51), with the outer balance ring member (75) and the inner balance ring member (77) being structurally independent from the other. The outer balance ring member (75) and the inner balance ring member (77) define a balance ring passage (71) which provides continuous fluid communication between a fluid inlet (53) or a fluid outlet (53) and the valve passages (61) in the rotatable valve member (51).

Abstract: A vacuum pump includes a housing assembly having an oil-reservoir chamber in which a lubricating oil is stored; a pair of screw rotors disposed in the housing assembly and engaged with each other; a pair of rotary shafts connected to the rotors, respectively; a plurality of bearings supporting each of the rotary shafts and having an opening; an oil-feed pump for feeding the lubricating oil from the oil-reservoir chamber to the bearing; an oil-circulation passage provided for circulating the lubricating oil from the oil-feed pump to the oil-reservoir chamber through the bearing; a cover provided at the opening of the bearing to close the opening of the bearing with a clearance remained, the cover permitting the lubricating oil to enter the bearing through the clearance; and an oil-escape passage provided adjacent to the bearing for returning to the oil-reservoir chamber the lubricating oil not entering the bearing.

Abstract: A viscous seal for fluid transfer devices that deviates from the conventional wisdom of avoiding contact between the seal and a rotating drive shaft of the fluid transfer device. Instead of avoiding contact, contact between the seal and drive shaft is used to effect axial alignment of a sealing sleeve with the shaft. As a result, the viscous seal is compliant in that the sealing sleeve can follow the axis of the drive shaft. Accordingly, the sealing sleeve can fit snugly around the drive shaft for more effective prevention of leakage of low or any viscosity fluid along the drive shaft, but without any significant radial load being applied to the sealing sleeve that might cause undue wear or damage due to galling.