Abstract: To reduce squeeze pressure peaks on meshing rotors of a gear pump, recesses are molded into the product duct wall in the meshing area, on the delivery side and the suction side. The recesses are formed with spherical segments or other continuously curved surfaces.

Abstract: Pump heads comprising at least two gear-pump chambers are disclosed. Each chamber comprises a housing which defines a corresponding pump cavity. Each cavity contains a driving gear and at least one driven gear and has a separate inlet and outlet. The pump cavities are hydraulically interconnected by a fluid conduit allowing passage whenever the pump chambers are pumping a fluid so as to generate a higher pressure in one cavity relative to the other cavity, of the fluid from the higher-pressure cavity to the lower-pressure cavity sufficient to maintain hydraulic prime of both cavities. The invention is particularly useful for ink jet printing applications.

Abstract: Fluid transfer apparatus comprising a fluid reservoir and a pump connected to the reservoir by a supply line, wherein the apparatus is configured so that vapor generated in the pump during periods of inoperation may escape from the pump cavity through the pump inlet, rather than being trapped in the pump cavity, and liquid may flow into the pump cavity from the supply line through the pump inlet to replace escaping vapor, thereby providing reliable pump start-up during intermittent operation. The apparatus may be employed to pump LNG for fueling of vehicles. Where LNG or another cryogenic fluid is being pumped, the pump is preferably driven by a motor located above the pump and connected thereto by an elongated shaft. Shaft seals may be provided to prevent the fluid being pumped from contacting the motor or the bearings supporting the motor shaft. A vapor trap may be provided beneath the shaft seals to prevent contact between liquid being pumped and the shaft seals.

Abstract: Apparatus and process for handling thermoplastic liquified material is disclosed. A system including an extruder feeding into a degasifying chamber is disposed upstream of a gear pump for pressurizing the material. The extruder gravity delivering, by way of a multiple-billet die, billets to the gears outside of the gear meshing area.

Abstract: In a tandem type gear pump, the housing body has an inner middle partition wall portion integral with the body and having bearing means. The housing body is formed at the opposite axial end faces thereof with a pair of recesses each shaped like a pair of glasses, with a pair of covers being fixed to the axial end faces of the body to close the recesses. A pair of gear pump units are set in the recesses so as to be rotatable by the bearing means in synchronism with each other. The housing is provided with inlet and outlet port means in communication with the gear pump units.

Abstract: The present invention relates to an apparatus for producing a controllable, uniform conveying pressure for processing highly viscous, temperature sensitive rubber or thermoplastics, consisting of two rotating conveying elements that form a toothlike sealing profile and are arranged on shafts in a housing. The root diameter of the conveying elements more or less corresponds to the diameter of the shaft sections that are axially adjacent to the conveying elements on either side and form bearing surface therefor. The radial faces of the conveying elements are thus avoided and so are the usually rather difficult sealing problems at these faces. By additionally providing either the shaft sections or the surrounding housing parts with return channels the channel volume of which decreases in the conveying direction, the axial sealing capacity of the gear pump is improved considerably.

Abstract: A device to separate muddy water from slurry which is being drained away and a means to use said muddy water to both seal and lubricate a gap between the guide channels and the vanes of the drainage pump, thereby securing the efficient long-term functioning of the pump. The invention presupposes the use of a vane type rotary drainage pump connected to a separation means which is set up to remove muddy water from the slurry discharged from the discharge port. A pressure chamber is incorporated into said rotor and connection with the inner ends of each of said guide channels. The muddy water separated out by the separation means is fed back into said pressure chamber.

Abstract: Method and apparatus for on-site cleaning of a gear pump by coupling the gear pump outlet to the gear pump inlet and to the inlet end of the passage and which bypasses the bearing and is preferably controlled by a valve element which can block off the bypass in normal operation and be opened for a cleaning operation to increase the pressure on the side of the bearing connected to the inlet and thereby increase the velocity of the flushing stream.

Abstract: A gear pump for pumping viscous material has a housing with an inlet and an outlet and a gear chamber between the inlet and the outlet. A pair of intermeshing gear wheels which are rotatably supported by bearings in the gear chamber of the housing have end faces in rotative contact with abutting faces of the housing. Spiral grooves in end faces of the gear wheels have a direction to move radially outwardly any material entering between end faces of the gear wheels and abutting faces of the housing to prevent such material from reaching the bearings. An integral drive shaft of one of the gears has a helical groove for preventing material from reaching bearings of the drive shaft. The driven gear has a central circular recess in which a bearing stud projects with bearing needles between the stud and the recess in the gear.

Abstract: A hydraulic fluid pressure energy translating device of the sliding vane type comprising a cartridge including a cam ring including an internal contour, a rotor having a plurality vanes rotatable therewith and slidable relative thereto in slots in the rotor with one end of each vane engaging the internal contour. The cartridge includes a rotor and has an internal contour cooperating to define one or more pumping chambers between the periphery of the rotor and the cam contour through which the vanes pass carrying fluid from an inlet port to an outlet port. Two pressure chambers are formed for each vane and each vane has two surfaces one in each chamber, both being effective under pressure in the respective chambers to urge the vanes into engagement with the cam. The cartridge further includes support plates.

Abstract: An externally driven rotor is rotatable within a pumping chamber and is located in meshing relationship with an internal idler gear. An annular bearing mounted within the housing in confronting relationship with a peripheral surface of the rotor, provides a bearing surface and supports radially directed loads exerted by unbalanced fluid force on the rotor. A pressure balancing circuit is provided for transferring pressurized fluid from a discharge region in the pump to a backside of the rotor to at least partially balance axial forces exerted on the rotor by pressurized fluid. To provide bi-rotational capability, a cross-communicating passage and check valves are used for controlling the flow of fluid into the pressure balancing circuit.

Abstract: A pump 10 for materials having a viscosity up to about 3.0.times.10.sup.5 cps, such as cellulose acetate, has a pump body 12 formed with a gear receiving means and, mounted thereon for closing the gear receiving means 13, a pair of side plates 16, 18 having bearing receiving cavities 21. The side plates 16, 18 have pressure relief means 50 for relieving pressure that builds-up in the intermesh of gears 14 when highly viscous material, such as cellulose acetate, is being pumped. This means of diverting the pressure buildup enables the pump 10 and component parts, such as shafts 22, 24 and plain bearings 20, to resist premature failure due otherwise to the resultant load caused by residual pressure buildup. In the preferred embodiment, wear resistant ceramic plain bearings 20 are press fitted in the bearing cavities. Grooves or channels 30 in the interior walls 32 of bearings 20 provide a means to lubricate shafts 22, 24 rotatably supported in the bearings 20.

Abstract: An improved sealing apparatus for gear transfer pump of the type that includes a gear driven by a drive shaft connected to a drive source. The drive shaft extends through a backhead which includes a seal system for inhibiting fluid leakage between the drive shaft and the backhead. The seal system includes a tubular insert held at one end by a support element threadedly received in an end bore of the backhead and structure defined by the backhead which engages another portion of the insert and includes a secondary seal for inhibiting fluid leakage between the insert and the backhead. The insert includes structure for mounting at least a portion of the seal in predetermined alignment with the drive shaft. The drive shaft includes an abutment for locating a rotating portion of the seal for applications that include two-part seals. A seal cartridge is disclosed in which non-rotating and rotating portions of the seal form a single assembly that is installed as a unit into the backhead.

Abstract: A screw compressor, having a housing with an inlet and an outlet opening in which two or more rotors are rotatably mounted on bearings. The bearings are equipped with helically meshing profiles which operate tightly in conjunction with a closely fitted cylindrical part of the housing. The bearing devices or the rotors consist at least in part of fluid bearings.

Abstract: A gear metering pump for delivering precise amounts of a compounded elastomeric material into a die. The gear pump has a housing formed with a hollow interior chamber containing a pair of rotating meshing gears mounted on shafts, one of which is power driven, for passing controlled quantities of the compounded material out of the chamber and into the die. A side plate is removably mounted on the housing and encloses an open side of the chamber and is moved between open and closed positions by fluid pressure cylinders mounted on the housing to provide ready access into the chamber for cleanout. A first bearing assembly for the gear shafts is mounted on the removable side plate and retains the gears mounted thereon for removing the gears from within the chamber along with the side plate.

Abstract: An internal gear pump includes a casing, a cover mounted to the casing, a pump chamber defined between the casing and the cover, an internal gear slidably arranged within the pump chamber, an external gear rotatably arranged within the pump chamber and rotatingly driven from the outside to engage with and drive the internal gear, a fixed filler for regulating sliding movements of the internal and external gears and for preventing oil leakage from a high-pressure side to a lower-pressure side within the pump chamber, a suction port formed in the cover and extended circumferentially within the angular range of about 90 degrees, an oil pocket device formed in respective sliding surfaces of the casing and cover, on which the opposite side surfaces of the internal gear slide, the oil pocket device having a plurality of taper lands extended within the radial width of from the root of tooth of the internal gear to the outer peripheral surface of the internal gear between the peripheral wall of the pump chamber and t

Abstract: A vane type hydraulic energy translating device for pumping filtered seawater and which uses seawater as a lubricating fluid. The pump is a compact, light weight design in which the bearings and certain other critical components are fabricated from corrosion resistant, low friction, high strength materials. The vanes as well as flexible side plate members are formed of these corrosion resistant materials. The pump body is formed of high corrosion resistant stainless steel. The side plates are flexible and act as wear surfaces for the ends of the vanes as well as sealing surfaces about the rotor thereby preventing leakage of seawater from high to low pressure areas. Each vane is spring biased radially outward from the rotor axis with four springs disposed within apertures located in the vane base. The vanes are generally rectangular in shape and have an outer end portion which serves as a sliding seal against a cam ring track.

Abstract: A gear pump having improved low-temperature operation includes a housing with a cavity wherein is rotatably received a pair of meshed pinion gears. A pair of bushing members matched in external shape to a projection of the pair of gears and complementary to the housing cavity alone journal the pair of gears. The bushings and gears are freely movable relative to the housing at all operating temperatures for the pump, and the bushings are urged by fluid pressure forces into sealing cooperation with the gears and with the housing. The pump achieves an improved pumping volume by directing a trapped intermesh volume to the outlet port of the pump.

Abstract: The roller-vane hydraulic machine comprises a hollow casing (1) having working fluid inlet and outlet passages (2, 3). The casing (1) is provided with hollows opening into the space of the casing (1), said hollows accommodating rollers (4) interacting with a rotor (5) located inside of the casing (1). The casing (1) is provided with vanes (6) which, together with the casing (1) form a working space (7) divided by the rollers (4) into larger and smaller inter-roller chambers (8, 9) intercommunicated in pairs by hydraulic relief passages (14, 15). The rollers (4) have slots for the passage of the vanes (6) of the rotor (5). The larger and smaller inter-roller chambers (8, 9) are intercommunicated in pairs by passages (14, 15, 16, 17) in the casing (1).

Abstract: A flowmeter has meshing rotors mounted on shafts. The bores of the rotors have plural longitudinally extending grooves which flow materials through the grooves and out of the bores to promote long, accurate running of the flowmeters. Radial faces of counterbores and end faces and lands of the rotor are provided with radial extensions of the axially extending grooves to provide flow of the material through the grooves.

Abstract: A hydraulic device includes a hydraulic motor having a wobble shaft driven by a rotor of a gerotor gear set. An outer end of the wobble shaft is received in a hollow inner end portion of an output shaft. A brake assembly holds the motor output shaft against rotation when the hydraulic motor is being operated. A seal blocks fluid flow between the brake assembly and the hydraulic motor. The seal is disposed in sealing engagement with the hollow end portion of the output shaft at a location between the motor and the brake assembly.

Abstract: A lubrication system for the main drive connection of a gerotor device, the lubrication system having a pressure operated piston valve connected directly off of the gerotor cells of the device for bi-directional circulation of fluid therethrough.

Abstract: A thrust plate for a gear pump or motor which permits the use of high pressure fluid from the outlet side thereof to lubricate the trunnions and bushings therein. The thrust plates include two small bores which pass therethrough the which are in fluidic communication with the inlet side of the pump via the surface of the thrust plate that confronts the gears within the pump. The foregoing bores are also in fluidic communication with the bushings by means of associated slots in the opposite side of the thrust plate. The opposite ends of the bushings are in fluidic communication with fluid at atmospheric pressure. By minimizing the size of the foregoing bores and by allowing the passage of fluid through same to the inlet side of the pump via the gear tooth confronting surface of the thrust plate, pressure gradients are created across the trunnions and their associated bushings.

Abstract: A vane type compressor comprising a main housing with a cylinder, a front side plate covering one end of the cylinder, a front housing over the front side plate for forming a suction chamber, and a rotor inserted in the cylinder with a rotatable drive shaft extending through bosses of the front side plate and the front housing. A seal is arranged in the boss of the housing, and a check valve is arranged in the front housing at the inlet thereof. To guide the fluid in the suction chamber to the seal, to improve the lubrication of the seal, a pair of guide walls are provided on opposite sides of the check valve and between the check valve and the suction ports to constitute a passage directed to the seal. Also, a pair of ribs is extended from the front side plate toward the seal to constitute a gap, the gap overlapping the passage.

Abstract: An improved, high-pressure fluid draining, internal gear hydraulic device of the type having a rotatable valve plate which selectively communicates inlet and outlet ports of a commutator with opening and closing fluid chambers between internal and external gear. The valve plate has radially extending drain ports which drain high pressure fluid from the area inside the valve plate to a check valve system outside the valve plate. This check valve system can drain to a low pressure fluid port of the device such as the inlet or outlet of the pump.

Abstract: A gear pump constructed in such a manner that bearing bushings are pressedly inserted in bushing insertion holes for supporting gear shafts therein, side plate are arranged on both sides of gears, and a part of hydraulic oil in a suction chamber is circulated through a lubricating oil introduction passage formed on an inside of each of the bearing bushings and a lubricating oil return passage formed on an outside of each of the bearing bushings. The lubricating oil return passages have outlets positioned in a manner to be laterally symmetric on the basis of a vertical line defined by connecting centers of the gear shafts and vertically symmetric on the basis of a horizontal line extending through a center of the vertical line and perpendicular to the vertical line. The side plates each are formed with a through-hole which is positioned on one side of the vertical line so as to be communicated to both outlets of the lubricating return passages vertically symmetric on the basis of the horizontal line.

Abstract: A variable vane-type pump in which a cam ring with variable eccentricity encompasses a rotary piston comprising vanes guided in radial slots. At least one lateral surface of the rotary piston abuts on the contact surface of a control disc with pressure pocket and suction pocket. A channel is provided in the control disc whose intake opening is disposed in the direction of rotation of the pump between pressure pocket and suction pocket and in direct vicinity of the end of the pressure pocket. The channel terminates in a housing chamber, the waste oil chamber, the lubricating channels and/or into the under-vane chambers. After displacement of the cam ring, a connection can be established between the channel and the pressure pocket so that the pressure fluid still delivered can discharge via the channel to safeguard lubrication of the pump.

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 lubrication system is provided for a motor of the type including a gerotor displacement mechanism (17), an inlet port (57), an outlet port (61), and valve means (19,55) operable to control the flow of fluid from the inlet port through volume chambers (29) of the displacement mechanisms and back to the outlet port, thus defining a main fluid flow path. A shuttle valve (85) communicates a flow of lubrication fluid from the main fluid flow path to a lubrication flow path (79,81,82,83) which flows through the bearings and spline connections of the motor. In accordance with the invention, a restrictor member 113 is located in the outlet port (61) and defines a restricted orifice 115 which restricts outlet flow from the motor causing a back pressure which generates the flow of lubrication fluid. After fluid flows through the lubrication flow path, it flows to the outlet port, downstream of the restricted orifice 115, recombining with the low-pressure, exhaust flow from the motor.

Abstract: A seal for the drive shaft of a gear pump for polymeric materials dissolved in a fluid solvent is disclosed, and which is adapted to prevent the polymeric material from leaking and hardening on the drive shaft. The seal includes a pair of axially spaced apart annular packing seals surrounding the drive shaft so as to define an annular chamber, and means for supplying a pressurized shielding inert gas, such as nitrogen, into the annular chamber. An outlet line is connected to the lowest portion of the annular space and leads to an air tight container which also contains a shielding inert atmosphere, and such that any polymeric material which leaks along the drive shaft and enters the annular chamber remains in solution, and is withdrawn into the air tight container. A valve is also provided on the container for periodically draining the withdrawn polymeric material therefrom.

Abstract: To avoid areas of slow moving or stagnant polymer in a gear pump feeding from an extruder to a die, the inlet port (7) has its cross-section changing progressively from that of the outlet (10) of the extruder to a slot section (11) at the demeshing region of the gear teeth, the slot section having a breadth at least equal to the breadth of the gears (3, 4) and a height between one and four times the gear teeth height, and the outlet port (8) preferably changes progressively from a similar slot section (16) at the meshing region of the gear teeth to the cross-section of the inlet (17) of the die.

Abstract: A rotary fluid pressure device (11) is disclosed of the type having a fluid displacement means (17), an inlet port (57), an outlet port (61) and a valve means (55) which cooperates with a housing (21;101;201) to define a main flow path communicating from the inlet to the volume chambers of the mechanism (17) and then to the outlet. The device includes an arrangement such as an orifice (89) or shuttle valve (111) having its inlet in communication with the main flow path downstream of the contracting volume chambers (29). The motor includes a lubricant flow path (81,83; 107,109; 207) which provides lubricant to the bearings and shaft splines. The orifice (89) or shuttle valve (111) provides a generally constant flow of lubricant despite variations in the motor load or motor speed.

Abstract: In gear pumps having an automatic lubricator, channels are provided for the delivery to and the discharge from the pump bearings, of lubricant, which consists of and is withdrawn from the medium to be conveyed. The conveying means for conveying the lubricant through the channels are mounted in the shafts of the gear pump. The channels can connect the suction side or the delivery side or the suction and delivery sides of the pump to the pump bearing.

Abstract: A hydrostatic machine having a rotor mounted in a housing and having a leakage oil connection, the leakage oil being conducted before discharge to the tank through predetermined housing portions in order to heat the central part of the housing during the start-up phase of the machine.

Abstract: A wet motor pump has an armature located in a motor chamber. A shaft bushing with an internal bore rotatably supporting a shaft end portion of an armature shaft is located in an outlet housing having a bore and a bushing support for receiving the shaft bushing. The bushing, end portion of the armature shaft, the internal bore as well as an end wall passage of the outlet housing structure defines an end chamber wherein are provided an end chamber inlet passage and an end chamber outlet passage for communicating the end wall passage and the wet motor chamber. A pressure differential structure establishes a pressure differential between the end chamber inlet passage and the end chamber outlet passage, to cause a fluid flow into the end chamber inlet passage, to cool and lubricate the shaft bushing, and therefrom out of the end chamber outlet passage forming a cooling and lubrication system.

Abstract: The bore of a bearing bush for a gear pump has a first recess located in a zone of load concentration in the bore, the first recess being supplied with a fluid under pressure. A second recess in the bore is located wholly outside the zone in which concentrated loads occur and acts as a reservoir for fluid, to prevent cavitation within the bore as a result of low pressures caused by radical movements of a shaft within the bush. A passage connects the second recess with a zone of lower pressure within the pump.

Abstract: There is shown a pressure loaded external gear pump with a low pressure lubrication system. The low pressure lubrication system utilizes the viscous shear pumping effect which occurs between the shafts and bearings to draw fluid from the inlet port, circulate it past the bearings and then return it to the inlet port.

Abstract: An oil pump assembly comprises a pump body assembly composed of a pair of front and rear pump bodies, the rear pump body housing in a pump housing space a pair of pumps each including a pump cartridge having a rotor supported on a common drive shaft rotatably supported on the front pump body, and a cam ring accommodating the rotor. A single side plate is axially slidably interposed between the pump cartridges. A pressure plate is disposed between one of the pump cartridges remote from the front pump body and a pump discharge pressure chamber defined at the bottom of the pump housing space and communicating with a main passage through which one of the pumps communicates with a discharge port. The other pump is selectively connected by a directional control valve to the main passage. The pump and valve parts can easily be assembled into the pump bodies, and hence the oil pump assembly can be mass-produced efficiently, less costly, and is small in size and lightweight.

Abstract: A rotary fluid pressure device is disclosed of the type including a roller gerotor (17) having a ring member (23) and a plurality of rollers (25) serving as internal teeth. At each end of each roller (25) is a side clearance space (85) and a small amount of lubrication fluid flows from each pressurized volume chamber through the side clearance spaces (85) into an adjacent lubricant recess (81). All of the lubricant recesses (81) are in communication with the fluid-collecting groove (79) and lubrication fluid flows from the groove (79) to the motor lubrication flow path. The lubrication flow path includes flow through a rearward bearing set (35); a forward bearing set (33); a pair of fluid passages (36); the forward splines (37, 39); and the rearward splines (43, 45). The invention results in improved lubrication generally, and of the forward splines in particular.

Abstract: A lubricating system for a scroll type compressor which includes a housing having a front end plate and a cup-shaped casing. A fluid inlet port is formed on the cup-shaped casing positioned opposite and opening onto a rotation preventing/thrust bearing device. In one embodiment, a cut portion may be formed in the fixed ring of the rotation preventing/thrust bearing device opposite the fluid inlet port. An oil passageway may then be formed in the front end plate to communicate between the cut portion and a shaft seal cavity.

Abstract: An improved pump assembly includes a plurality of pumping elements which rotate with a rotor and engage an inner surface of a cam ring to define pumping chambers which hold liquid and/or air. As the pumping chambers move along an inlet arc, liquid flows through an orifice to the chambers. The orifice restricts the rate of flow of liquid to the pumping chambers to a flow rate which is insufficient to fill the chambers with liquid during high speed rotation of the rotor. As the pumping chambers move along an outlet arc which has a constant slope toward the rotor, the volume of each pumping chamber is decreased. When the fluid pressure in the pumping chamber exceeds a pump discharge pressure, one of a series of a check valves opens and fluid is discharged from the pumping chamber.

Abstract: A seal for the drive shaft of a gear pump for melted polymeric materials is provided, which includes a reduced pressure zone, a mechanical packing seal, and a liquid filled chamber positioned in succession along the drive shaft. The liquid is a solvent for the polymeric material, and it is maintained under a pressure slightly above that in the reduced pressure zone. Thus a small quantity of the liquid tends to move axially into the reduced pressure zone where it dissolves any polymeric material leaking thereinto. A failure of the seal may be readily detected by monitoring the volume of the liquid, since any polymeric material leaking axially through the packing seal will be dissolved by the liquid in the chamber, thereby increasing the volume of the liquid.

Abstract: A compact hydraulic motor 10 in which a pressurized sleeve bearing 20 is coaxial with a commutator 16, all positioned in the output housing 14. The commutator housing provides fluids to a rotary valve plate 48 and to chambers 52 formed between rotating inner member 30 and orbiting outer member 32. The sleeve bearing 20 is pressurized with fluid from the gear set 30, 32 and is in fluid communication with a rear needle bearing 24. The seals are protected from overpressurization through channels 25 and 46 and pressurization valves. In an alternate embodiment of the invention, dual gear sets 80, 82, and 81, 83, (FIG. 7) are positioned within a housing for either series or parallel operation. Fluid directed to the two gear sets by a manifold 112 can run the gear sets in parallel or series in order to provide either high speed low torque or low speed high torque operation.

Abstract: A sealing chamber is defined between the front head and the front side block. The drive shaft on which the rotor is rigidly fitted is journalled by front and rear plain bearings provided on the front and rear side blocks, respectively. The bearing on the front side has an end portion remote from the rotor enclosedly disposed in the sealing chamber. The sealing chamber communicates in a direct manner with the suction port formed in the compressor casing by way of a passage means so as to be supplied in a direct manner with suction refrigerant having a low temperature and a low pressure.

Abstract: A gear pump structure is provided having a housing with a pump chamber, a suction chamber and a discharge chamber communicating with said pump chamber on opposite sides thereof, a suction port and a discharge port in said housing communicating respectively with the suction chamber and discharge chamber, each of said ports have spaced apart inlet and outlet means, said suction port being contoured to provide on introduction of fluid into the inlet end a point intermediate its inlet and outlet means having a pressure higher than the pressure at the inlet and outlet means, at least one pair of meshing gears mounted for rotation in said pump chamber and each having two axially spaced trunnions, a plurality of bearing means in said housing each having an axial bore mounting said trunnions for rotation in the pump chamber, drive means for rotating said gears so that liquid which is drawn through the suction port into the suction chamber is engaged by teeth on said gears and transferred to the discharge port under p

Abstract: The invention relates to a hydraulic pump or motor having inlet and outlet ports and expansible chamber section at one end thereof, which may be a gerator gear set, and a drive shaft at the other end thereof. A distributor valve driven by the drive shaft and having a central bore directs fluid between the inlet and outlet ports in the housing and the expansible chamber section. A shaft, such as a cardan shaft, disposed in the central bore of the valve provides a driving connection between the valve and the expansible chamber forming section. Although a bearing is provided in the housing for the drive shaft, the distributor valve is also subjected to radial loads because the cylindrical surface thereof has a close fitting sealing relationship with the housing bore in which it is rotatably disposed. Lubrication for both ends of the cylindrical surface of the valve is provided by passages extending from valve passages which carry the motive fluid controlled by the valve.

Abstract: A dynamic cooler apparatus is provided for dynamically cooling molten plastic extrudate while pumping metered amounts of that extrudate to an extrusion die or the like. The dynamic cooler apparatus utilizes bi-helical gears in a gear pump configuration in a housing in which a heat exchange medium is circulated. The heat exchange medium is also circulated internally of the gears so that the gear teeth and the housing act to cool discrete volumes of extrudate from four sides defined by the gear teeth and the internal surface of the housing. The bi-helical gears are driven to minimize loading between the teeth thereof and to permit the teeth to be as small as practical to present more cooling surface for a given cross-section of extrudate and optimize the heat transfer capability of the dynamic cooler apparatus. Provision is also made to use the molten extrudate as a lubricant for the shafts and bearings of the bi-helical gears.

Abstract: A liquid pump has a drive shaft which extends through a housing. The high pressure side of the pump is connected through a radial channel with an annular channel formed in the housing surrounding the drive shaft. High pressure liquid in the annular channel prevents the ingesting of air by the pump.

Abstract: Gear pump and motor apparatus adapted to operate both as a pump and as a motor include two meshing gears whose shafts are supported in a housing chamber by respective bearing sleeves whose end faces sealingly engage the end faces of the respective gears. An oil supply passage is formed in each of the bearing sleeves in a region diametrically opposed to flat surface portions formed on the outer peripheral surface of the bearing sleeves and near a central plane which passes through the axes of cylindrical chamber portions in which the gears are situated. Oil leaking from the pump/motor chamber is directed into spaces defined between the peripheral surfaces of the bearing sleeves and the respective chamber portions through the oil supply passages into the bearing sleeve openings to lubricate the gear shafts which are received therein. The ratio of the length to the diameter of each of the oil supply passages is less than or equal to about 10.

Abstract: An improved rotary compressor of sliding vane type in which a rotor head portion is provided where the peripheral surface of the rotor approaches the inner peripheral surface of the cylinder so as to divide the interior of the cylinder into a discharge side and a suction side for fluid, while the cylinder is formed with a seal portion where a clearance between the rotor and cylinder at the rotor head portion is formed into a wedge-like configuration in a rotational direction by an arc having a radius of curvature smaller than a radius of the cylinder.