Abstract: A turbomachine that can be operated as a motor and as a pump, having an axially fixedly mounted shaft, including a power section with rotating inlet and outlet and an associated controller. Because the axial forces (Fgx) have been made independent of the sense of rotation the turbomachine is significantly more reliable, and because the sealing forces have been adjusted it has significantly greater reliability (?) in both running directions. It can be operated with fluids and gases. The turbomachine can be extended by adding a control device and a drive for the control device so as to provide a freewheel function, a braking function and/or blocking function, and so as to shift, modify and optimize the characteristic curves across the entire control range. In both the clockwise and anticlockwise directions the turbomachine has in principle the same properties, although these can be modified and optimized by the control device.

Abstract: An apparatus and method of producing a pump including a housing and a cam received within the housing that is rotatable relative to the housing. The cam includes an axis of rotation. The pump further includes a retainer plate operable to abut the cam to restrict movement of the cam in a first direction along the axis of rotation. The pump further includes a biaser, such as a spring, operable to place a first constant force in the first direction on the retainer plate.

Abstract: A pump (10) comprising a casing (12) that encloses a pumping group (14). On the casing (12) at least one inlet conduit (F) and at least one outlet conduit are obtained. The pumping group (14) comprises a pair of mutually coupled gears defining a pump chamber. A first support shaft (16) is operatively connected to an actuator assembly (18) so that the first gear can operate as a driving gear to set the second gear in rotation. The pump (10) comprises at least one element (20) for compensating the increase in volume of the fluid (F) and/or the increase in the pressures inside such a pump (10). The element (20) for compensating the pressure/volume is at least partially manufactured from a shape memory metal alloy having superelastic properties.

Abstract: A pump having a stroke ring which has an axial recess, a rotor which is received in the axial recess so as to be rotatable relative to the stroke ring, wherein the rotor has radial recesses in which delivery elements are displaceable received as viewed in a radial direction, a side plate which closes off the axial recess on a first side, a pressure plate which closes off the axial recess on a second side, wherein the pressure plate has at least one opening, wherein a pressure region of the pump is fluidically connected to external surroundings of the pressure plate through the at least one opening, and wherein at least one fluid path is provided from the pressure region of the pup into an under-vane region of the delivery elements, and a cold-start plate which is preloaded against the pressure plate by means of a spring element such that, at least when the pump is at a stand-still, the cold-start plate closes the at least one opening in the pressure plate to the external surroundings of the pressure plate.

Abstract: A rotary vane pump or rotary vane motor including a rotatable rotor being eccentrically arranged within a rotatable cylindrical housing sleeve defining a freely rotary working chamber which takes out the relative sliding movement and friction inside to outer housing bearing. A partition element of a vane hingedly attached to the rotor; wherein the partition element travels with the rotor following the orbit of the housing incident to the expansion and contraction of the working space performing as a true dynamic radial seal; The rotor assembly along with the housing assembly being sandwiched between end-plates to fulfill dynamic side seal; The end-plates may contain pressure and non-pressure ports as well as holes for shaft, bearings, brackets and mounting hardware.

Abstract: The invention relates to an apparatus for sealing a pump chamber of a rotary lobe pump vis-a-vis a fluid-free region of the rotary lobe pump, in particular in the region of a shaft duct, wherein the apparatus has two or more sealing elements, which can be disposed adjacent to a front side of a rotary piston disposed on a shaft in the pump chamber of the rotary lobe pump in such a way that a labyrinth gap extends between the sealing elements, said labyrinth gap being arranged in a radial direction relative to the shaft and in an axial direction in order to extend the seal land. According to the invention, the seal land is larger in a radial direction relative to the shaft than the seal land in an axial direction relative to the shaft.

Abstract: A balance shaft module having a variable capacity hydraulic pump may include a first balance shaft that receives torque from an engine and a first unbalance mass is formed, a second balance shaft that receives torque from the first balance shaft through a connection gear, and a hydraulic pump that suctions and discharges oil by the rotation of the second balance shaft and varies its capacity depending on oil pressure discharged.

Abstract: A pump unit of a vane-type pump having no dedicated housing including a drive shaft, a rotor that interacts with the drive shaft and accommodates vanes, a contour ring surrounding the rotor, and a first and a second side plate which are disposed laterally of the contour ring.

Abstract: A self-adjusting gear pump is disclosed. The pump may be a crescent internal gear pump, a gerotor pump, or an external gear pump. The pump includes a pump housing, gear housing, first and second gears, a side plate housing with a side plate, a shim and an end plate. The side plate moves between a first position contacting the first and second gears and gear housing, and a second position contacting the end plate. The side plate is spring biased toward the first position. A method is disclosed for match grinding the crescent plate (if used), gear housing and gears as a unit to provide a uniform surface. The side plate housing and side plate are similarly match ground. An assembly method is disclosed which allows the crescent plate to be moved with respect to the gear housing so that clearances between the crescent and the gear teeth are eliminated.

Abstract: An air compression device is applied in an air compressor, and mainly includes a first rotor, a second rotor, a stop disk, a transmission element and a drive element. When external air enters an air chamber in the air compression device, the air is rotated and compressed by the first rotor and the second rotor, and then is exhausted, the transmission element generates axial displacement vertically according to actual requirements on air admission or exhaust, and drives the drive element and the first rotor to displace, so as to change a capacity of the air chamber, and adjust the air output.

Abstract: Positive-displacement auxiliary pumping systems for use in pump apparatus of different configurations are disclosed. The positive-displacement auxiliary pumping systems are included in positive-displacement rotary pumps having a casing defining a pumping cavity, an inlet port connected to the pumping cavity, a discharge port connected to the pumping cavity, and a positive-displacement auxiliary pumping port connected to the pumping cavity. Pumping elements move within the pumping cavity of the casing and define a collapsing pocket that maintains fluid communication with the positive-displacement auxiliary pumping port after the collapsing pocket is no longer in fluid communication with the discharge port.

Abstract: A vane pump includes a housing defining a pump chamber; a rotor rotatably arranged in the pump chamber; and a motor to rotate the rotor. An imaginary plane is defined to bisect the pump chamber in an axis direction. The housing has a first inlet port and a second inlet port located symmetrical with each other with respect to the imaginary plane, and the housing has a first outlet port and a second outlet port located symmetrical with each other with respect to the imaginary plane.

Abstract: A rotary fluid pressure device includes a gerotor gear set having a ring gear and a star gear orbitally moveable about a longitudinal axis relative to the ring gear. The star gear includes an annular spacer ring disposed at one end of the star gear. A brake pin is moveable along the longitudinal axis into and out of interlocking engagement with the annular spacer ring. The brake pin includes an outer surface for engaging an interior surface of the spacer ring. The outer surface of the brake pin and the interior surface of the spacer ring are each angled relative to the longitudinal axis to engage each other in a tapered engagement, to generate an axial force along the longitudinal axis to move the brake pin out of engagement with the star gear in response to a torque being applied to the star gear.

Abstract: The invention concerns a vane cell machine with a stator and a rotor having radially displaceable vanes arranged in guides, said vanes bearing on an inside of the stator and bordering, together with the rotor, the stator and a side wall, work chambers at each axial end of the rotor. It is endeavoured to provide a vane cell machine that has a good internal tightness, in which the wear is still kept small. For this purpose, in a radially internal area the side wall comprises an insert that is axially movable in the side wall and has a pressure application surface axially inside and axially outside.

Abstract: An upper casing receives a rotor, which is rotated by a drive force of a motor. The upper casing includes a pump chamber, which receives the rotor, a planar surface portion, which is formed around an opening of the pump chamber, and a through hole. A lower casing includes a planar surface portion, which is formed around the opening of the pump chamber, and a through hole. The lower casing closes the opening of the pump chamber to form the pump chamber in cooperation with the upper casing. A resilient sheet is placed between the lower casing and a mount portion of the motor and includes a through hole. A screw is received through the through holes of the upper casing, the lower casing and the resilient sheet to securely connect the upper casing, the lower casing and the resilient sheet to the mount portion. A lower casing side surface of the resilient sheet includes a plurality of primary protrusions.

Abstract: A pump device comprising a first side plate arranged at one axial side of a drive gear and having a first contact surface contacting to a first side surface of the drive gear, a friction coefficient of the first contact surface being smaller than that of the first side surface of the drive gear, a second side plate arranged at the other axial side of the drive gear and having a second contact surface contacting to a second side surface of the drive gear, a friction coefficient of the second contact surface being smaller than that of the second side surface of the drive gear and a seal member incorporated with the first and second side plates to constitute a pump chamber, the seal member sealing tops of teeth of the drive gear and having a friction coefficient that is smaller than that of the tops of the teeth.

Abstract: A vane pump includes a motor, a rotor rotated by the motor, a first casing having a pump chamber accommodating the rotor and a first flat part in a periphery of an opening of the pump chamber, a second casing having a second flat part joined to the first flat part to gas-tightly or liquid-tightly close the opening of the pump chamber, an elastic sheet disposed between the second casing and the motor, and a screw penetrating the first casing, the second casing and the elastic sheet. The screw is configured to fasten and join the first casing, the second casing and the elastic sheet to the motor.

Abstract: A gear pump has a pump housing formed with a gear receiving recess, a pump cover coupled with the pump housing to cover the gear receiving recess, a hydraulic passage that uses the gear receiving recess as a passage part thereof, and annular inner and outer gears operatively installed in the gear receiving recess. The inner and outer gears are of a bevel type and meshed with each other in such a manner as to bias the inner gear in a direction to reduce the thickness of the passage part when the inner gear is rotated while turning the outer gear therearound.

Abstract: A laminate material web has two webs of nonwoven fabric that lie on the outside, and film strips of an elastic film disposed between them, in sections, whereby the nonwoven fabric webs are connected with one another in the regions between the film strips. The film strips are connected with the inner surfaces of the nonwoven fabric webs only at the two longitudinal edges, in each instance, both on the top and on the bottom, and the nonwoven fabric webs have weakenings running in the web direction, in the regions that cover the film strips. A method for the production of a laminate material web is also described.

Abstract: The invention relates to a sealing device for a swivel motor comprising an outer part and an inner part as well as at least one working chamber located between them, which seals the working chamber and comprises at least two rectangular sealing element housed in a groove enclosed in the outer and/or inner part running essentially parallel to the swivel axis of the swivel motor, each of which comprises at least one rectangular sealing plant and at least one gasket.

Abstract: A pump, particularly a vane pump or roller cell pump, whereby the vane pump or roller cell pump is provided with a two-stroke contour ring, with a rotor, inside of which vanes or rollers are mounted in a manner that enables them to be radially displaced, with at least one side side plate, which seals the rotating group, with a casing and with a casing cover, whereby the rotor is driven by a shaft and the shaft is mounted inside the casing and, optionally, inside the cover.

Abstract: A side face of a pump gear is formed into a stepped face such that an annular region extending radially from a diameter which is smaller than a dedendum circle diameter of the pump gear and larger than the outer diameter of a pump gear bearing to the addendum circle diameter of the pump gear is recessed by a certain depth to increase the side gap in the recessed annular region. Therefore, the side gap in the recessed annular region is larger than a side gap in a region between the diameter smaller than the dedendum circle diameter of the pump gear and larger than the outer diameter of the pump gear bearing to the outer diameter of the pump gear bearing.

Abstract: A fluid pump assembly comprises a pump housing and a fluid pump disposed within the pump housing. The fluid pump has axially opposite first and second side faces and includes cooperating impeller and rotor members. The fluid pump assembly further comprises inlet and outlet ports disposed adjacent to the first side face, a pressure chamber formed within the pump housing adjacent to the second side face, and an end plate disposed within the pressure chamber and movable relative to the pump between a first position and a second position. The end plate has axially opposite inner and outer end surfaces oriented so that the inner end surface faces the fluid pump, while the outer end surface faces away from the pump. An area of the outer end surface of the end plate is greater than the area of the inner end surface thereof.

Abstract: A hydraulic vane pump includes a plurality of members forming a recession and an orifice in fluid communication with one another and with rotating vane cells at an inlet sector of the pump. Air entrained in the vane cells is exhausted through the recession and the orifice prior to fluid passing from the inlet sector to a discharge sector, thereby increasing pump capacity and decreasing cavitation noise. A method of pumping fluid in a vane pump to decrease cavitation noise is also provided.

Abstract: A bearing is located with movement of an outer race in the longitudinal direction of a drive shaft being restricted, and the drive shaft is fixed to an inner race 51c with the press fit, so that, it is possible to prevent the drive shaft from escaping. In addition, the inner race is longer than the outer race. Therefore, it is possible to obtain sufficient strength of the press fit of the drive shaft in the inner race 51c while suppressing the size of the outer race (in other words, suppressing the size of the pump device). As a consequence, the size of the pump device can be suppressed while increasing reliability of the function for preventing the drive shaft from escaping.

Abstract: A rotary positive displacement hydraulic machine includes a housing defining two mutually intersecting parallel working chambers having a low pressure inlet side and a high pressure outlet side. Two meshing rotors are mounted for rotation in the two chambers, respectively. Bearing supports at opposite ends of the chambers, support bearings in which the rotors are journalled for rotation. At least one end of the housing is closed by an end cover. The end cover and adjacent housing end have at least one elongate recess on each side of the working chambers. The end cover recesses are alignable with the housing recesses. There is at least one keying element in each pair of aligned recesses so that the open end of the housing is supported against relative movement by differential fluid pressure in the chambers in a direction transverse to a plane containing the axes of rotation of the meshing rotors.

Abstract: A rotor includes a plurality of vanes and is connected to a rotatable shaft of a motor arrangement. A casing includes a pump chamber and elongated holes. The pump chamber receives the rotor in such a manner that the rotor is eccentric to the pump chamber. Each elongated hole penetrates through the casing and has an elongated cross section. A major axis of the elongated cross section of each elongated hole extends in a direction of eccentricity of the rotor relative to the pump chamber. Each bolt is received through a corresponding elongated hole of the casing and is threadably engaged with a mount to connect the casing to the mount. The casing holds each bolt in a minor axial direction of the elongated cross section of the corresponding elongated hole to limit substantial movement of the male threaded screw member in the minor axial direction of the elongated hole.

Abstract: A vane pump includes a motor arrangement, a rotor, a casing and bolts. The motor arrangement includes a mount. The rotor includes vanes and is rotated by the motor arrangement. The casing has opposed first and second end surfaces and makes flat surface contact with the mount at the second end surface thereof. The casing includes a pump chamber, receiving through holes and second end side recesses. The pump chamber receives the rotor. The receiving through holes penetrate through the casing. The second end side recesses are recessed in the second end surface of the casing. The second end side recesses are spaced away from the receiving through holes. Each bolt is received through a corresponding one of the receiving through holes of the casing, and each bolt is threadably engaged with the mount to connect the casing to the mount.

Abstract: A novel bi-rotational pump adapted to pump fluid in either of two directions by reason of construction inclusive of passageways and an array of check valves and pilot pistons which cooperate in one direction and in another way in the other direction.

Abstract: A rotary vane suction pump that includes a housing that defines a pump chamber. A shaft is rotatably mounted to the housing. A rotor is fixed to the front end of the shaft to rotate in unison with the vanes. The vanes that form the fluid cavities, into which the fluid is drawn into and discharged from, are seated in radially directed slots that extend longitudinally, end-to-end along the length of the rotor. Discs located at the opposed inboard and outboard ends of the rotor are mounted to the shaft and rotor to turn in unison with the rotor. The discs have diameters greater than that of the rotor and the pump chamber. The discs thus close the ends of the pump chamber and the ends of the slots in which the vanes are seated.

Abstract: A hydraulic pump system having a pump for pressurizing fluid and a hydraulic chamber for receiving fluid from the pump. An even flow of fluid is outputted from the chamber to a valve assembly. The chamber is formed from a resonator and a resonator cover that are attached in a fluid tight manner by elastic fasteners. The resonator cover acts as a pressure controller in that when the pressure of fluid is of sufficient magnitude, this force creates a gap for controlling fluid pressure output to the valve assembly.

Abstract: A hydrostatic transmission and a charge pump for supplying operating oil which are housed in a housing, in which a pump casing of the charge pump is mounted to a center section of the hydrostatic transmission without using mounting bolts. A spring is interposed between the pump casing and the inner surface of the housing. For defining pump discharge pressure, the center section receives all of the radial force generated in the pump casing. Between the center section and the charge pump is interposed a plate of material made of less friction resistance so as to reduce the sliding resistance. The charge pump is simple in construction and inexpensive to produce.

Abstract: An improved self-lubricating bearing arrangement for gear pumps utilizes a system of material feed channels and reservoir pockets to divert a portion of the material being pumped from the pressure side of the intermeshing gears to lubricate the gear-supporting shafts within the bearing arrangement. At each gear shaft, a linear material feed channel is formed in the radial face of the bearing between a pressure relief recess and an axial opening supporting the shaft and a parabolic reservoir pocket is formed within the bearing opening adjacent the shaft to apply diverted polymer to the shaft. Each material feed channel and reservoir pocket is polished to a mirror finish to minimize any tendency of suspended additives in the polymer from adhering to or collecting within the channels or pockets, thereby to prevent unusual or localized wearing of the gear shafts.

Abstract: A sliding vane air pump has a resilient flexible plate secured to the housing adjacent to one end of the rotor so that drawing a high vacuum flexes the plate closer to the rotor to further increase the vacuum attainable by the pump.

Abstract: Internal gear pump with an internal gear, a thrust plate arranged on each side of the internal gear, a powered external pinion arranged eccentrically relative to the internal gear and meshing with it, and a sickle-shaped, floating filler part split in peripheral direction and bearing with its blunt end on an axial support pin. The first segment of the filler part that faces the teeth of the pinion has a greater radial thickness than its second segment facing the teeth of the internal gear. The first segment features in the parting interface at least one axially extending groove for accommodation of a sealing element. The first segment features at least one stop for restricting wear on the surface facing the teeth of the pinion.

Abstract: A rotary vane machine includes a rotor having one or more sliding vanes. The rotor rotates within a chamber of a housing. At least one sealing plate is located between an end surface of the rotor and a corresponding inner surface of the housing. The sealing plate improves the seal between the rotor surface and the inner housing surface.

Abstract: A pump or motor device (22) includes a housing (24) which encloses a rotor (30) disposed within a cam ring (46). A bottom or wear end plate (100) and a top or pressure end plate (156) cooperate with the cam ring (46) and vanes (42) connected with the rotor (30) to form working chambers. The rotary device (22) may be assembled for either a clockwise or counterclockwise rotation. When the rotary device (22) is to be assembled for clockwise rotation, a first set of end plates (100 and 156) is used. When the rotary device (22) is to be assembled for counterclockwise rotation, a second set of end plates (130 and 204) is used. The second set of end plates (130 and 204) includes end plates which are mirror images of the corresponding end plates (100 and 156) in the first set of end plates.

Abstract: A pump gear for force-feeding of a non-Newtonian fluid has a pair of gears with intermeshing teeth, each flanked by members such as bearings with inner surfaces opposite to its side surfaces. The gaps that are formed between the side surfaces of the gears and the inner surfaces of the flanking members are tapered such that their width increases radially, making the speed of fluid flow substantially uniform throughout inside the gaps.

Abstract: The balanced vane hydraulic pump designed for automotive power steering applications employs a two-piece aluminum housing construction, a cam ring, rotor flow regulating valve, a high pressure gallery, and a pressure plate, all located in the rear housing section, and a set of needle bearings located in the front housing section for supporting the pump drive shaft from one end only. The pressure plate has a sculpted portion which communicates with the cam ring side of the pressure plate. The sculpted portion is a wishbone-shaped gallery and a low pressure area, recessed within the face of the pressure plate. The pressure plate also includes high pressure windows which deliver high pressure fluid from the cartridge to the high pressure gallery located within the rear portion of the pump housing.

Abstract: A rotary positive displacement hydraulic machine such as a gear pump or motor, comprises a housing defining two mutually intersecting parallel working chambers, two meshing rotors mounted for rotation in the two chambers, respectively, and two bearing supports at opposite ends of the parallel chambers and each supporting bearings in which the two rotors are journalled for rotation. The housing is open at one or both ends. The or each open end of the housing has a hollow, non-circular spigot which is received in a recess of matching non-circular shape defined by a continuous flange projecting from a peripheral region of a respective bearing support in a direction parallel to the axes of rotation of the meshing rotors and which is surrounded by a shoulder extending from the spigot to the peripheral edge of the housing, so that the or each open end of the housing is supported by its bearing support against outwards movement in a plane transverse to the axes of rotation of the meshing rotors.

Abstract: A reversible, self-priming rotary pump has a housing with a stator of elastomeric material which is softer than the elastomeric material of the rotor on a cam on shaft. The inlet and exhaust ports are separated by a lobe received in a recess in the stator. As the shaft is rotated, the rotor orbits within the stator to pump the fluid between the inlet and exhaust ports, the stator being at least partially compressed along the line of contact with the rotor to form an efficient seal therebetween.

Abstract: A gear pump is disclosed which is adapted to convey a polymeric melt without significant leakage, and which comprises a pair of intermeshing gears. One of the gears is driven by a drive shaft which extends through a journal bore in the pump housing, and a by-pass duct extends between the journal bore and an area in the internal chamber of the pump which is adjacent but spaced from the intermeshing teeth and where the fluid cells defined by the intermeshing teeth are expanding. Also, at least one root of one of the gears includes a channel which leads to the area of the by-pass duct, and so that an intermittent suction resulting from the expanding fluid cells acts to withdraw any melt from the journal bore of the drive shaft and through the by-pass duct, to thereby prevent leakage of the melt outwardly through the journal bore.

Abstract: An improved adhesive pump and pump control system for automatically changing the flow rate of adhesive materials being dispensed onto a workpiece in conformance with changes in movement of a robot controlled adhesive dispensing nozzle used to apply adhesive materials automatically onto the surface of the workpiece in accordance with a predetermined pattern. The system includes an improved adhesive gear pump having a novel sealing arrangement which employs lubricant grease supplied under pressure for preventing leakage of the adhesive along the shaft into the bearings of the pump thereby assuring long and reliable operating life for the pump under normal operating conditions.

Abstract: Variations in pump capacity of gear pumps due to varying leakage paths occurring in otherwise identical pumps as a result of the manufacturing operation are minimized without unduly hindering the fitting of the bearings through the pump housing by maintaining the distance "TBD" between the center of the bearing journal and the bearing flat closely within tolerances and by providing a relief in the bearing periphery diametrically opposite of the flat.

Abstract: A rotary positive-displacement fluid-pressure machine of bi-directional type including a casing, intermeshing rotors, and a pressure-balancing arrangement, associated with the end face, remote from said rotors, of the or each end plate means of the machine. Each arrangement comprises sealing means which separate a plurality of areas on said end face, certain being subjectable to high, and others to low, fluid pressures. A further area defined by further sealing means and subjectable only to high fluid pressure is in a zone opposite, and is in positional correspondence with, that zone of the face of the end plate means engaging the rotors which is in registry with the region where the rotors mesh. The further area extends through and beyond the common plane of the rotor axes towards the low pressure side of the machine.

Abstract: Rapid wear in a gear pump construction due to shaft deflection during pump operation and of the sort including a housing having an interior wall defining a pumping chamber, opposed inlet and outlet ports meshed gears within the chamber, a pair of shafts mounting the gears and bushings journalling the shafts is avoided by providing at least some of the bushings near their ends remote from the gears and on their sides remote from the outlet with radially outwardly opening slots extending generally transverse to the shafts.

Abstract: A planetary hydraulic motor comprises a housing (1) with a stator gear (2), the housing accommodating a shaft (3) having fixedly secured thereon a gear (4), a ring rotor (11) disposed eccentrically relative to the shaft (3) and two cover cups (5 and 6). The shaft (3) has a sealing assembly in the form of a thrust ring (7) secured in the cover cup (5) and a sleeve (8) having a cylindrical projection adjoining by the end face thereof the working surface of the thrust ring (7). Mounted on the outer surface of the cylindrical projection of the sleeve (8) is a ring element (20) fabricated from an elastic material. Provided in the sleeve (8) essentially under the ring (20) are passages (21) adapted to communicate a section of the inner surface of the ring (20) with the atmosphere.

Abstract: An arrangement for centering an end wall of a housing of a hydraulic gear machine, such as a pump or a motor, with respect to the open end of an internal chamber provided in a housing body forming the circumferential wall of the housing includes a plurality of pins which are received in a press-fitting manner in bores of the end wall and protrude beyond an end face of the end wall which faces and closes the open end of the chamber in the mounting position. The pins may have contact surfaces which are turned to the same diameter as the corresponding inner surface of the housing body which bounds the open end of the chamber, or they may exactly fit into the open end, or overlap slightly with the inner surface in which event some material displacement or deformation takes place during the assembly of the end wall with the housing body.

Abstract: A tubular cylindrical housing encloses an eccentrically mounted rotor provided with radial slots receiving the inner ends of slideable vanes, the outer ends of which are connected to wiper bars which ride along the interior peripheral surface of the housing. Opposed rotatable sealing plates disposed between the ends of the rotor and the ends of the housing are concentric with the interior of the housing and carry the ends of the wiper bars. Gear trains synchronize the rotation of the discs and rotor.

Abstract: A hydraulic device, pump or motor, useful with the hydraulic fluid used in a mine. The device comprises a housing with an impeller within the housing. A drive shaft extends through the housing and carries the impeller. There are bearings for the shaft on either side of the impeller. The improvement is an isolator member positioned between each bearing and the impeller chamber to prevent contact between the bearing and the pumped hydraulic fluid. The invention reduces the damage to hydraulic pumps and motors without increasing fire risk within the mine and helps conserve oil. This latter advantage applies to use of the invention anywhere, including use outside a mine.