Showing papers on "Gear pump published in 1997"

Micro gear pumps for dosing of viscous fluids

Abstract: Gear pumps using micro gear wheels with diameters of 596 and and a height of have been realized at IMM by means of a combination of LIGA technology and precision engineering. Using oil as pumping medium the pumps achieve back pressures of more than 1200 hPa and flow rates of up to . The self-filling pumps tolerate air bubbles and particles contained in the working medium. The gear pumps displace 82 and 213 nl respectively per revolution, i.e. they offer the possibility of very precise dosing of viscous fluids, such as oil.

Infinitely variable ring gear pump

Abstract: An infinitely variable ring gear pump comprising a stationary casing, an internal rotor (3) in said casing rotatably supported and driven by means of a shaft (2) and an external rotor (4) likewise rotatably supported, meshing with the internal rotor (3), the difference in the number of teeth of the gear ring running set comprising the internal rotor (3) and the external rotor (4) being equal to unity, having a tooth shape in which a plurality of expanding and contracting displacement cells (7) each sealed off from the other materializes due to tooth tip contact and kidney-shaped low and high-pressure ports (8, 9) fixedly arranged laterally in the region of the displacement cells (7) being provided in the casing, the ports (8, 9) being separated from each other by webs (10, 11) and the angular position of the eccentric axis (eccentricity 17) of the ring gear running set (5) being variable relative to the casing. The support (12) of the external rotor (4) of the ring gear running set (5) occurs at the outer diameter (13) of the latter in an adjusting ring (14) preferably the same in width which is rollable with zero slip by its outer circumferential or pitch circle (15) on an inner circumferential or pitch circle (16). The difference in the diameters of the two circumferential or pitch circles (15, 16) equals twice the eccentricity (17) of the ring gear running set (5).

Gear pump for use in an electrically-operated sealed compressor

Abstract: A gear pump is used in an electrically-operated sealed compressor. The compressor includes a compression mechanism, an electric motor for driving the compression mechanism, and a crankshaft for transmitting the rotational force of the electric motor to the compression mechanism. The gear pump includes a pair of gears being in mesh with each other, one of which is connected to one end of the crankshaft, and a pump casing accommodating only the pair of gears. The pump casing together with the gear pair is disposed on one side of a cover plate, while other elements constituting the gear pump are disposed on the other side of the cover plate. By this construction, the distance between the gear pair and an auxiliary bearing to which the gear pump is secured can be reduced and, hence, an undesirable whirling of one end portion of the crankshaft can also be reduced.

Pressurized fluid supply system

Abstract: The present invention has an object to enable to supply a discharged pressurized fluid of a hydraulic pump without any energy loss with an arbitrary flow rate distribution ratio to a plurality of actuators. A discharged pressurized fluid of the hydraulic pump 11 is supplied to the first and second actuators 15 and 16 via the first and second variable displacement type hydraulic pump/motors 13 and 14. The first variable displacement type hydraulic pump/motor 13 and the second variable displacement type hydraulic pump/motor 14 are mechanically connected to rotate at the same revolution speed. By this, the pressurized fluid is supplied to the first and second actuators 15 and 16 depending upon displacements of the first and second variable displacement type hydraulic pump/motors.

Variable speed transmission and transaxle

Abstract: A variable speed transmission or transaxle that utilizes a pump for variable braking of the output shaft or axle A rotatable input shaft connectable to a drive source extends into a transmission housing and is operatively connected to a gear train that transmits rotational power to a transmission output shaft A gerotor pump mounted within the housing utilizes a ring gear of an epicyclic gear of the gear train as an inner gerotor gear that meshes with an outer gerotor gear to pump fluid along a fluid conduit By adjustably varying the resistance of the pump, the revolution rate of the epicyclic ring gear is adjusted which in turn results in a controlling of the speed of rotation of the transmission output shaft In an alternate embodiment, a reversible transmission is provided by employing two gerotor pumps and two gear trains which allow forward and reverse speeds of rotation of the output shaft to be variably controlled

Wheel braking system

Abstract: A wheel braking system comprises a motor driven gear pump, a relief line connecting the pump discharge to the pump intake, a wheel brake unit connected to the pump discharge, and a flow restriction in the relief line. A control unit controls the motor for the pump in response to an output signal of a brake pedal sensor. The brake pedal sensor generates the output signal indicative of the brake pedal stamping force. The control unit determines a desired motor speed for the sensed brake pedal stamping force and operates the motor.

Hydraulic pump control system

Abstract: A hydraulic pump control system is shown that can control the absorbing torque of a hydraulic pump with respect to the engine power for driving the hydraulic pump in a well-balanced manner, and reduce a deviation of an actual revolution number from a target revolution number of the engine. A torque of hydraulic pumps during operation is estimated from a pump pressure and first and second line pressures. Based on the estimated torque, an output torque of the hydraulic pumps is controlled so that an error between a target revolution number and an actual revolution number of the engine becomes null.

Development of LIGA-fabricated, self-priming, in-line gear pumps

Abstract: This paper reports the development and characterization of the self-priming, magnetically-actuated, two-gear plastic pump which is fabricated by the sacrificial LIGA process. This positive displacement, in-line pump provides a flow rate of 350 /spl mu/l/min at 5000 rpm, over 140 cm-H/sub 2/O (/spl sim/2 psi) of head pressure and 28.8 cm-H/sub 2/O vacuum on the suction side for a single stage pump. It is the first non-diaphragm, microfabricated pump. A two stage in-line pump generated 533 mm-H/sub 2/O vacuum at its inlet (21" H/sub 2/O). This performance demonstrates a viable, microfabricated alternative to syringe pumps and compressed gas for moving fluids in micro-instrumentation.

Oil pressure generator having at least two coaxial rotating power sources and power output apparatus

Abstract: An oil pressure generator 20 includes a drive gear 30, a driven gear 32, and a crescent 34, which constitute a gear pump unit, as well as one-way clutches 36 and 38 that respectively interlock with two rotating shafts 42 and 46 when the rotating shafts 42 and 46 rotate in an identical direction relative to the drive gear 30. In case that both the rotating shafts 42 and 46 rotate in the interlocking direction, the corresponding one-way clutch interlocks with the rotating shaft having a greater revolving speed, thereby driving the drive gear 30. This structure enables the oil pressure generator 20 to produce an oil pressure through rotation of the rotating shaft having a greater revolving speed out of the two rotating shafts 42 and 46.

Gear pump with meshing internal and external toothed wheels

Abstract: The gear pump has an inner gearwheel with external teeth eccentrically mounted inside an outer gearwheel with internal teeth. The housing in which the gearwheels fit has an inlet (45) and an outlet (46) connection at right-angles to each other, extending radially towards the cylindrical chamber in which the gearwheels rotate. There is a filler piece (36) in the crescent-shaped space between the two gearwheels. This has a D-section support rod (38) at its leading edge with its ends held in the side cheeks of the housing. There is a curved, tapered carrier piece (65) behind this rod, supporting a curved sealing strip (66).

Method and device for monitoring system units based on transmission of lumped characteristic numbers

Abstract: A method is provided for monitoring the operating status of one or more pumps, particularly gear pumps, whereby system parameters are determined by a corresponding measuring device. The system parameters are subsequently processed in a local evaluation unit into characteristic numbers. Finally at least some of the characteristic numbers determined in the local evaluation unit are transmitted from the pump and/or the local evaluation unit to the central evaluation unit. Based on the characteristic numbers, the operating status of the pump is determined and if necessary, an appropriate action is triggered.

Liquid fuel pressurization and control method

Abstract: A liquid fuel pressurization and control system is disclosed which utilizes either a helical flow pump, or a helical flow pump followed by a gear pump, to pressurize liquid fuel to precisely the pressure level required by a turbogenerator's combustor injectors. This eliminates the need to overpressurize the fuel then regulate the fuel pressure down using a flow control valve or a pressure control valve. The shaft torque and shaft speed of the pump are controlled by the turbogenerator's power controller so as to assure that the turbogenerator's speed is precisely controlled (e.g. within ten (10) rpm out of one hundred thousand (100,000) rpm), and that its turbine exhaust temperature is precisely controlled (e.g. within two (2) degrees Fahrenheit out of twelve hundred (1200) degrees Fahrenheit) over the full range of turbogenerator electrical output power. The system also provides cool, high pressure air to assist atomization of the liquid fuel in the injectors utilizing a variable speed helical flow compressor. The system also adjusts the relative fuel flow through the multiple fuel injectors to aid flame stability at low turbogenerator speeds and low output power levels.

Control of lubrication and temperature of the bearings of a pump

Abstract: A method and apparatus for transporting a solution of cellulose in an amine oxide solvent using a gear pump (11) having a pump body (12) and a pair of meshing gear wheels (15, 16) mounted on shafts (17, 18) rotatable in bearings (21) fixed relative to the pump body (12). The temperature of at least one of said bearings (21) is monitored and used to control the volume throughput of the pump (11) in dependence on the monitored temperature.

Gear coatings for rotary gear pumps

Abstract: Gears for pumping non-lubricating fluids at high pressure are provided which include special coatings. One of the gears is coated with a combination of nickel and polytetrafluoroethylene; the other gear is coated with a combination of carbon and tungsten carbide. Because the coatings are different and have different hardnesses, galling is prevented. Preferably, the gears are fabricated from stainless steel and, therefore, in the event a scratch or nick in the coating is produced, corrosion is prevented. The gears are useful for gear pumps used to pump fire fighting liquids and foam at high pressures.

Oil pump adaptor

Abstract: An adaptor for mounting a high capacity external oil pump to an original equipment engine block having existing openings for mounting an external oil pump. The adaptor bolts on existing bolt holes in the engine block. Sump oil is routed through the adaptor into the high volume oil pump. The high volume gear pump is driven, through the adaptor, by the previously existing original equipment engine block mechanism and through the previously existing opening provided for driving the original equipment gear pump. The adaptor has openings for accepting dirty sump oil from the engine. Dirty sump oil is directed through a cavity to the intake side of the high capacity gear pump. An oil filter is provided on the gear pump cover. Orifices direct the pressurized oil from the gear pump to the filter. The filtered pressurized oil is returned to the engine by mating orifices in the adaptor, gear pump, and gear pump housing.

Integrated motor/gear pump

Abstract: Pinion and ring gears intermeshed at one location within a pump chamber are rotationally supported therein by a cylindrical bearing portion of a housing sealingly enclosing said pump chamber between side plates of the housing within which stator windings are mounted in operative alignment with permanent magnets carried in one of the gears acting as a motor rotor as a result of interaction between such magnets and magnetic fields produced by electrical input power fed to the stator windings.

Gear pump with noise attenuation

Abstract: An apparatus comprises a reservoir (14) containing hydraulic fluid (68), a gear pump (16) with a suction hole (74), and a hydraulic muffler (18). The gear pump (16) has gears (78) with meshing teeth (80) that convey a flow of hydraulic fluid (68) from the reservoir (14) into the pump (16) through the suction hole (74). The muffler (18) attenuates noise by damping flow rate fluctuations that are caused by the meshing gear teeth (80). The muffler (18) includes a compliant element (92) and a fluid inertia structure (90) interposed between the suction hole (74) and the fluid (68) in the reservoir (14). The inertia structure (90) responds to the flow rate fluctuations by directing corresponding hydraulic pressure fluctuations to deflect the compliant element (92). As a result, noise is attenuated upon deflection of the compliant element (92).

Multi-speed transmission for electric power tools

Abstract: A multi-speed transmission for electrical power tools with a rotatable tool has a machine housing, a working spindle supported in the housing for rotating the tool, an electric motor, a gear reducer shaft which is driven by the electric motor, a planetary transmission arranged between the working spindle and the gear reducer shaft, the planetary transmission including a sun gear, planetary gears and a planetary gear carrier, the planetary gear carrier being coupled with the gear reducer shaft, the sun gear being formed switchably so that it is coupled for joint rotation with the machine housing for a slower speed and with the working spindle for a faster speed.

Compact manual transaxle for motor vehicles

Abstract: A compact manual transaxle includes an input shaft having four fixed input gears, a first intermediate shaft rotatably supporting three speed gears meshing with three of the input gears, a second intermediate shaft rotatably supporting a pair of speed gears meshed with two of the input gears and a reverse gear meshed with a speed gear on the first intermediate shaft, and a differential. One speed gear on each of the intermediate shafts meshes with a common input gear. A transfer gear on each intermediate shaft is meshed with a final drive gear fixed to the differential. The transaxle further includes a pair of synchronizer clutches for establishing three forward gears by selectively coupling the three speed gears to the first intermediate shaft and a pair of synchronizer clutches for establishing two forward gears and the reverse gear by selectively coupling the speed gears and reverse gear to the second intermediate shaft.

Hydrostatic gear combined with mechanical gear

Abstract: The hydromechanical transmission may be used in a tracked vehicle. It has a hydrostatic gear with a mechanical gear, and a planetary gear mechanism, both driven by a motor. The hydrostatic gear output works together with the mechanical gear to achieve an infinitely-variable flow of power through the hydromechanical gear. The planetary gear has three sets of planetary gears and five links, linking the hydromechanical gear with the output.

Centrifugal flywheel pump with two section

Abstract: The pump has at least two pump sections each with a suction area and a pressure area. A fluid path leads from the pressure side to consumer, and a hydraulic resistance element is set in another fluid path connecting the pressure areas. The hydraulic resistance element can be a cold start plate (17) through which the pressure areas can be separated. The pump has a radially aligned rotor (7) with slits receiving the vanes, a pressure plate (11) sealingly adjoining the end side of the rotor and a fluid connection between the pressure side of the pump and an under-vane area.

Thrust actuator driven by motor

Abstract: PROBLEM TO BE SOLVED: To make possible the large equivalent gear ratio of a thrust actuator driven by motor and generate its large thrust without making small the number of the teeth of its input gears, by configuring each of its reduction gears through the gear train comprising the combination of gears whose number is not smaller than a specific one. SOLUTION: A reduction gear is configured by the combination of three or more gears. Providing a front-side sun gear 1f at the left end of a rotor 1b and a rear-side sun gear 1g at the right end of the rotor 1b, one-portions of front-side and rear-side reduction gears 2, 3 are configured respectively. The front-side and rear-side reduction gears 2, 3 comprise respective two front-side and rear-side planetary gears 2b, 3b provided respectively around the front-side and rear-side sun gears 1f, 1g, and respective two front-side and rear-side internal gears 2a, 3a provided respectively on the outsides of the gears 2b, 3b and in an actuator housing 7. The respective two front-side and rear-side planetary gears 2b, 3b are all fastened rotatably to front-side and rear-side planet carriers 2d, 3d by axes 2c, 3c. As a result, changing the numbers of the teeth of the internal gears 2a, 3a and sun gears 1f, 1g one by one on the front and rear sides, the large equivalent gear ratio of a thrust actuator driven by motor can be achieved.

Continuously variable annular gear pump

Abstract: The pump has a stationary housing (1) and an annular ring set (5) with inner rotor (3) and meshing outer rotor (4). The gear ration of the inner rotor and the annular ring set is equal to 1. The bearing (12) of the outer rotor along its outer diameter (13) is inside the adjusting ring (14) of preferably the same width. The adjusting ring moves slip-free with its outer part circle (15) on an inner part circle (16). The difference between the diameters of the two part circles is double the eccentricity (17) of the ring set.

Hydraulic transmission for bicycles

Abstract: The hydraulic pump (42) connected to the bicycle's pedal crankshaft (25) is a vane cell pump with one or more feed cells (101). The peripheral edge face of at least one cell is formed by a displacement valve (90) which is radially adjustable in relation to the pump drive shaft (25). The displacement valve encompasses the pump drive shaft by an angle which is larger than the central angle of a feed cell.

Tribology of Hydraulic Pumps

Abstract: To obtain much higher performance than that of alternative power transmission systems, hydraulic systems have been continuously evolving to use "high-pressure". Adoption of positive displacement pumps and motors is based on this reason. Therefore, tribology is a key technology for hydraulic pumps and motors to obtain excellent performance and durability. In this paper the following topics are investigated: 1. The special feature of tribology of hydraulic pumps and motors. 2. Indication of the important bearing/sealing parts in piston pumps and effects of the frictional force and leakage flow to performance. 3. The methods to break through the tribological limitation of hydraulic equipment. 4. Optimum design of the bearing/sealing parts used in the fluid to mixed lubrication regions.

Gear pump channel arrangement for tempering media

Abstract: In order to cool the slide bearing area for the slidable bearing of a gear pump shaft, a slide bearing bush with a slide bearing area and, in the case of the guiding-through of a shaft, a sealing area extends in one piece integrally to the outside, and a cooling-medium guiding system provided in the bush is connected from the outside. This eliminates all sealing problems for the cooling medium feeding to the slide bearing area.

Gear pump having members with different hardnesses

Abstract: An improved gear pump having members with different hardnesses includes a housing defining an internal bore with inlet and outlet passageways. A head member includes a wall between the inlet and outlet passageways and extends toward a toothed rotor. A toothed idler gear meshes with the rotor. The head member and idler gear are made of materials having a hardness greater than that of the rotor material. In one embodiment the idler gear is made of ceramic material whereas the head member and rotor are made of cast iron, with the head member treated to have a hardness greater than that of the rotor.

Oil pressure generator and power output apparatus

Abstract: An oil pressure generator 20 includes a drive gear 30, a driven gear 32, and a crescent 34, which constitute a gear pump unit, as well as one-way clutches 36 and 38 that respectively interlock with two rotating shafts 42 and 46 when the rotating shafts 42 and 46 rotate in an identical direction relative to the drive gear 30. In case that both the rotating shafts 42 and 46 rotate in the interlocking direction, the corresponding one-way clutch interlocks with the rotating shaft having a greater revolving speed, thereby driving the drive gear 30. This structure enables the oil pressure generator 20 to produce an oil pressure through rotation of the rotating shaft having a greater revolving speed out of the two rotating shafts 42 and 46.