Abstract: A hydraulic gear pump for the oil lubrication system of an automobile engine is disclosed, and wherein the meshing teeth of the gears define fluid cells which are expanded in the intake portion and receive the fluid from an inlet, and then compressed in the discharge portion to expel the fluid. The inlet to the pump includes at least two parallel fluid lines which are each connected to a tank. A pressure controlled valve is connected to one or both of the fluid lines, and during the normal operating range of output pressure, the valve is controlled by the pressure in the pump discharge chamber so as to decrease the flow through the lines from a maximum flow rate to a lower flow rate as the output pressure increases. In the event the engine and oil are cold, the output pressure will increase beyond the normal operating range, since the oil consumption is small.

Abstract: A hydraulic gear pump is disclosed wherein the meshing teeth of the gears define fluid cells which are expanded in the intake portion and receive the fluid from an inlet, and then compressed in the discharge portion to expel the fluid. The contact ratio of the cooperating driving flanks of the meshing teeth is smaller than the contact ratio of the cooperating sealing flanks of the meshing teeth, which serves to minimize the power requirement of the pump. The inlet to the pump includes at least two parallel lines which are each connected to a tank, and the first line is provided with a fixed throttle and the second line is provided with a pressure control valve which is controlled by the pressure in the pump discharge line.

Abstract: A gear pump is disclosed which is adapted to produce a large number of independent output streams, and which includes a housing having a cylindrical opening, a toothed gear disposed coaxially within the cylindrical opening, and at least one pinion gear disposed within the cylindrical opening and mounted in meshing engagement with the toothed gear. A plurality of enclosed fluid chambers are disposed in an equally spaced apart arrangement about the periphery of the toothed gear during orbital rotation of the pinion gear, which in one embodiment includes a tooth cover positioned forwardly of the pinion gear, and in another embodiment comprises the spaces between the teeth of the toothed gear. A fluid inlet is provided for delivering a fluid to the cylindrical opening and to each of the enclosed fluid chambers, and a fluid outlet having a one way valve also communicates with each of the fluid chambers.

Abstract: A rotary vane vacuum pump assembly is disclosed which is characterized by the absence of the discharge of lubricating oil with the exhaust airstream, and which includes an internal stator and a surrounding rotor. Pivotal vanes are mounted on the interior of the rotor, so as to define a plurality of air chambers which expand and contract as the rotor rotates about the stator. Also, a freely rotatably cylindrical sleeve is positioned between the stator and vanes, so that the relative sliding contact of the vanes on the surface of the sleeve is minimized, to thereby eliminate the need for internal oil lubrication. In one preferred embodiment, a hydraulic pump is joined to the vacuum pump to form a compact assembly, and wherein the hydraulic pump supplies oil to the bearings which mount the rotor.

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: A hydraulic gear pump is disclosed wherein the meshing teeth of the gears define fluid cells which are expanded in the intake portion and receive the fluid from an inlet, and then compressed in the discharge portion to expel the fluid. The fluid is expelled to a common discharge chamber through a plurality of outlets which are positioned along the rotational direction and which are separated by a distance corresponding to the pitch of the gear teeth. The inlet to the pump includes at least two parallel lines which are each connected to a tank, and the first line is provided with a fixed throttle, and the second line is provided with a pressure control valve which is controlled by the pressure in the pump discharge chamber. The inlet may include a third parallel line, which is provided with a further valve and which is controlled by an externally monitored parameter.

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: A gear pump is disclosed which is adapted to produce a large number of independent output streams, and which includes a housing having a cylindrical opening, a toothed gear disposed coaxially within the cylindrical opening, and at least one pinion gear disposed within the cylindrical opening and mounted in meshing engagement with the toothed gear. A plurality of enclosed fluid chambers are disposed in an equally spaced apart arrangement about the periphery of the toothed gear during orbital rotation of the pinion gear, which in one embodiment includes a tooth cover positioned forwardly of the pinion gear, and in another embodiment comprises the spaces between the teeth of the toothed gear. A fluid inlet is provided for delivering a fluid to the cylindrical opening and to each of the enclosed fluid chambers, and a fluid outlet having a one way valve also communicates with each of the fluid chambers.

Abstract: A positive displacement reciprocating pump for conveying a liquid or gaseous fluid is disclosed and which comprises a fluid enclosure having a movable piston means mounted therein which sealably divides the enclosure into a pumping chamber on one side and an actuating chamber on the other side. The piston means may comprise either a slideable piston or a flexible diaphragm. An inlet valve and a separate outlet valve are each connected to the pumping chamber, and a control system is provided for intermittently supplying a pressurized working fluid to the actuating chamber so as to intermittently move the piston means in the discharge direction, with the piston means being moved in the opposite or suction direction by either the pressure of the fluid being conveyed, or a suitable spring.

Abstract: A rotary vane pump is disclosed which comprises a cylindrical housing, and a cylindrical rotor eccentrically mounted for rotation within the housing. The rotor includes a slot mounting a pair of oppositely oriented hook-shaped vanes, so as to define a hook space adjacent each end of the overlying vanes. A fluid, such as lubricating oil, is delivered to each hook space during that portion of its rotation shortly before its bottom dead center position, and the delivered fluid is pressurized during that portion of its rotation shortly after its bottom dead center position to assist in moving each vane outwardly from its bottom dead center position.

Abstract: A positive displacement reciprocating pump for conveying a liquid or gaseous fluid is disclosed and which comprises a fluid enclosure having a movable piston means mounted therein which sealably divides the enclosure into a pumping chamber on one side and an actuating chamber on the other side. The piston means may comprise either a slideable piston or a flexible diaphragm. An inlet valve and a separate outlet valve are each connected to the pumping chamber, and a control system is provided for intermittently supplying a pressurized working fluid to the actuating chamber so as to intermittently move the piston means in the discharge direction, with the piston means being moved in the opposite or suction direction by either the pressure of the fluid being conveyed, or a suitable spring.

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 method and apparatus for lubricating a vacuum pump, preferably a rotary vane vacuum pump, wherein the pump rotor is mounted on a hollow drive shaft continuously fed with a lubricating oil stream under excess pressure from an oil pump, radial openings being provided in the hollow shaft for the outward supply of lubricating oil to the elements being lubricated with the lubricating oil stream from said oil pump being fed under excess pressure as a pulsating and preferably intermittent flow stream into the interior of the hollow shaft.

Abstract: A motor fuel feed pump with a tappet operated piston or membrane wherein the tappet is linearly guided and sealed in a housing segment which projects into the cylinder chamber of the pump on its suction side or its pressure side with inlet and outlet means positioned such that the motor fuel flows around and in direct contact with the projecting housing segment.

Abstract: A rotary vane pump is provided which comprises a cylindrical housing, and a cylindrical rotor mounted within the housing. The rotor includes a number of radial guide slots extending axially along the length of the rotor, with each slot having a depth along at least a portion of its axial length which extends to the axis of the rotor. A blade is slideably disposed in each slot, and has a height which generally corresponds to the depth of the slot. This arrangement permits the rotor to be compact in size, and yet able to provide an adequate area of contact between the blades and rotor slots in the extended position of the blades.

Abstract: A hydraulic flow control apparatus is provided which is adapted to provide a constant pressure differential between a pump and an external load. The apparatus includes a housing, and a balance piston slideably mounted therein. The pump pressure acts to bias the piston in a direction toward a pump bypass position, and the piston is urged in the other direction and toward its operating position by the consumer pressure and a spring. Means are also provided whereby the pressure of the pump necessary to move the piston toward its bypass position and against the force of the spring, may be minimized during operation in the idling mode, to thereby minimize power consumption.

Abstract: A hydraulic flow control apparatus is provided which is adapted to provide a constant pressure differential between a pump and an external load. the apparatus includes a housing, and a balance piston slideably mounted therein. The pump pressure acts to bias the piston in a direction toward a pump bypass position, and the piston is urged in the other direction and toward its operating position by the consumer pressure and a spring. Means are also provided whereby the pressure of the pump necessary to move the piston toward its bypass position and against the force of the spring, may be minimized during operation in the idling mode, to thereby minimize power consumption.

Abstract: An improved rotary vane machine assembly of the type utilized for producing vacuum in motor vehicle power brake assistance units wherein a compensating coupling connects the pump drive shaft with the drive motor of the pump and a lubricant is supplied to the working elements of the pump from said drive motor, the improvement comprising a pot-shaped hood which receives the working components of the pump and, in particular, the rotor and vanes, and a mounting flange having a bell-shaped foot portion surrounding the compensating coupling and a lid portion covering the open end of the pot-shaped hood. A compensating disc which limits the operating chamber of the working components in an axial direction is also disclosed, the compensating disc being pressed against the face of the vanes by means of a cushion of lubricant and/or a compression spring.

Abstract: An improved design for sealing and lubricating the moving parts of a rotary vane pump. An effectively operating lubricant distributing system is obtained in such a pump by forming radially extending passages through the pump drive shaft and attached rotor which connect the lubricant carrying hollow portion of the drive shaft with chambers located between the base of the vanes and the slits formed in the rotor in which the vanes radially slide. The rear bearing in which the drive shaft rotates is connected to these vane base chambers by means of an annular compartment having a lubricant duct connected thereto, thereby insuring the continuous flow of lubricant from the hollow portion of the drive shaft, through the vane base chambers and into the rear bearing. In an alternative embodiment of the present invention, the front bearing of the pump is connected with the hollow portion of the drive shaft via a lubricant passage formed on the suction side of the vanes.

Abstract: An improved design of a rotary vane-type vacuum pump which prevents the oil used to lubricate the moving parts of the pump from entering the intake line of a connected vacuum chamber. The improvement comprises forming the inlet port in the front face of the cover plate which seals the end of the rotor casing. Filters are positioned in the intake port to catch any oil flowing along the inner wall of the intake port and to condense any oil foam entering therein. In order to facilitate the condensing of the oil foam, the inlet port is divided into two connected chambers, the lower of said chambers being of sufficient capacity to collect said oil foam flowing from the pump during its operation. A check valve is also positioned in the inlet port ahead of said filters in order to prevent the vacuum pressure in the vacuum chamber and intake line from dissipating through the pump and oil mist being drawn into the intake port when the pump is stopped.