Showing papers on "Gear pump published in 2003"

The Theoretical Flow Ripple of an External Gear Pump

Abstract: In this paper, the theoretical flow ripple of an external gear pump is studied for pumps of similar size using different numbers of teeth on the driving and driven gears. In this work, the flow ripple equation is derived based upon the flow of incompressible fluid across the changing boundaries of a control volume. From this method, it is shown that the instantaneous length of action within the gear mesh determines the instantaneous flow ripple. A numerical and a closed-form approximation are presented for the instantaneous length of action and it is shown that the difference between these two solutions is negligible. Fast Fourier transform analysis is employed for identifying the harmonic frequencies and amplitudes of the flow pulse and these results are compared for 16 different pump designs. In summary, the results of this study show that the driving gear dictates the flow ripple characteristics of the pump while the driven gear dictates the pump size. As a result, it may be advantageous to design an external gear pump with a large number of teeth on the driving gear and a fewer number of teeth on the driven gear This design configuration will tend to reduce both the physical pump size (without reducing the volumetric displacement of the pump) and the amplitude of the flow pulsation, while increasing the natural harmonic frequencies of the machine.

Fluid pump/generator with integrated motor and related stator and rotor and method of pumping fluid

Abstract: A fluid pump integrated with a motor, a fluid pump/generator device, a rotor for a fluid pump/generator device, a stator for a fluid pump/generator device and a method for pumping fluid are disclosed. Specifically, a fluid pump includes a motor rotor having a plurality of magnetic vanes that electromagnetically interact with a plurality of magnetic poles of the motor stator such that the rotor functions simultaneously as the impeller for the pump and rotor for the motor, with fluid flowing through channels on the rotor. Pump and motor are tightly integrated into one single device so that the number of parts is reduced, total size is compressed, reliability of the device is improved, and cost efficiency is increased. In addition, the use of magnetic vanes for propelling fluid improves motor efficiency. Further, the fluid flow is used to directly cool the pump/generator device, which reduces energy consumption.

Power system and work machine using same

Abstract: Engineers are constantly seeking methods to reduce undesirable emissions, noise, and vibrations created by power systems. In the present invention, a power system includes at least one hydraulic cylinder that defines a first fluid volume and a second fluid volume separated from one another via a moveable plunger. Hydraulic power created within the hydraulic cylinder is converted to mechanical energy by a variable displacement hydraulic motor that is fluidly connected to at least the first fluid volume. A generator is attached to the variable displacement hydraulic motor, and produces electrical power that is stored in a power storage system. The stored power can be supplied to an electric motor that is operable to power a hydraulic pump. The hydraulic pump supplies hydraulic fluid to the hydraulic cylinder. The power system of the present invention is a relatively efficient alternative to a power system including a diesel engine that can be a source of undesirable emissions, noise and vibrations.

Electro-mechanical actuator for an electrically actuated parking brake

Abstract: An electrically actuated parking brake system and actuator (102) therefor. The actuator (102) includes a motor (200) having a drive shaft, and a gear train coupled to the drive shaft, wherein the gear train provides at least one mechanical output from the actuator (102). The gear train may include a drive gear (202) coupled to the drive shaft, a driven gear (204) coupled to the drive gear (202), and a planetary gear set (206) coupled to the driven gear (204). Various configurations are provided for isolating actuator components for controlling audible noise, including sub-frame isolation configurations, motor isolation configurations, and gear train isolation configurations.

Hydraulically assisted gear shift mechanism for a marine propulsion device

Abstract: A hydraulic assist mechanism for use in conjunction with a gear shift device provides a hydraulic cylinder and piston combination connected by a linkage to a gear shift mechanism. Hydraulic pressure can be provided by a pump used in association with either a power trim system or a power steering system. Hydraulic valves are used to pressurize selected regions of the hydraulic cylinder in order to actuate a piston which is connected, by an actuator, to the gear shift mechanism.

Internal meshed gear pump

Abstract: The internal gear pump includes a driving shaft, a small gear connected with driving shaft and formed into one body, inner geared ring which is mutually engaged with said small gear, cover mounted inthe pump body and can be freely rotated and front and back pump covers mounted in the pump body. Between the circular surfaces of outside circules of the small gear and inner geared ring a stopping pin and a movable semicircular block are set for separating low pressure cavity from high perssure cavity. Two sides of the described small gear and inner geared ring are equipped with left and right two float side boards on which a back pressure oil cavity and elastomer are respectively set, and on the external cylindrical surface of the inner geared ring and on the central position directed toward every tooth point several holes are axially distributed.

Method and apparatus for maintaining hydraulic pressure when a vehicle is stopped

Abstract: A system for maintaining hydraulic pressure in a vehicle hydraulic system when the vehicle is stopped or idling. A hydraulic pressure reserve system includes a primary hydraulic circuit that includes a hydraulic pump and a hydraulic sump and that provides hydraulic pressure to at least a hydraulically actuated transmission and an accumulator tank and control valve connected from the primary hydraulic circuit for storing a reserve of hydraulic fluid at an accumulator pressure. An accumulator control valve, such as a bi-directional valve, allows a flow of hydraulic fluid between the primary circuit and the accumulator tank according to the primary circuit pressure to raise the primary circuit pressure towards a desired pressure. The hydraulic pressure reserve system may include a primary gear connected from a primary drive and driving an auxiliary secondary gear with a primary drive clutch for connecting the secondary gear to drive the hydraulic pump and an auxiliary drive clutch for connecting the auxiliary secondary gear or a drive chain to drive the hydraulic pump.

Delivery of pitch/thermoplastic/thermoset resins in RTM systems

Abstract: Resin or pitch is melted in a melt blender apparatus ( 11 ) and then loaded, into a heated jacketed holding tank ( 12 ) A pair of feed lines ( 14, 16 ) receives resin from the holding tank ( 12 ) and feeds an upper gear pump ( 15 ) and a lower gear pump ( 17 ) A mixing enhancement such as a static mixer ( 18, 19 ) is located in each of the feed lines ( 14, 16 ) between the gear pumps ( 15, 17 ) and the resin delivery ends ( 25, 26 ) of the feed lines The resin-melt feed lines may be equipped with pressure indicators ( 27, 28, 32, 34 ) and pressure relief valves ( 23, 24 ) The resin-melt feed lines may also be equipped with pump accumulators ( 31, 33 ) Resin melt pressure created by the gear pumps ( 15, 17 ) forces a piston inside the accumulator back to the desired position The accumulators ( 31, 33 ) can also be used to maintain constant pressure in the feed stock Resin can be recycled from the accumulators ( 31, 33 ) into the melt blender ( 11 )

Electric internal gear pump

Abstract: A novel motor-integrated electric internal gear pump that is compact and has a structure where a main shaft can be stably supported. A pump has a rotor section (4) with an outer rotor (25) and an inner rotor (26), an electric-motor section (3) rotating the inner rotor (26), and a main shaft (5) in which a drive shaft of the electric-motor section (3) and a rotation shaft of the inner rotor (26) are coaxially arranged and integrally constructed. The main shaft (5) is supported only by a first bearing (10) and a second bearing (16) that are at axially both sides of the shaft. The rotor section (4) is provided between the bearings (10, 16).

Pressure and film thickness in a trochoidal hydrostatic gear pump

Abstract: In this paper, a vector analysis is used to describe precisely the geometry of a hydrostatic gear pump from which full general parametric equations are deduced. A detailed kinematic analysi...

Speed-increasing gear for wind power generation

Abstract: PROBLEM TO BE SOLVED: To provide a speed-increasing gear for wind power generation, which sufficiently supplies lubricating oil to gears used such as planetary gears and is built in simple construction. SOLUTION: The speed-increasing gear for wind power generation is equipped with an input-side gear mechanism 1 and an output-side gear mechanism 2. The input-side gear mechanism 1 has an input shaft 19, a carrier 9, planetary gears 7, and a sun gear 6. The output-side gear mechanism 2 has a first gear 25 rotated by the rotation of the sun gear 6, a second gear 26 rotated by the rotation of the first gear 25, and an output shaft 4 rotated by the rotation of the second gear 26. The speed-increasing gear is also equipped with a first lubricating oil supply means 41 supplying lubricating oil to the sun gear 6, a second lubricating oil supply means 42 supplying lubricating oil between the planetary gears 7 and a ring gear 8, and a third lubricating oil supply means 43 supplying lubricating oil to a meshing-start part 40 between the second gear 26 and a gear part 30. COPYRIGHT: (C)2005,JPO&NCIPI

Pressing tool for pressing coupling elements

Abstract: A pressing tool having an electric motor fed by a battery. The electric motor drives a gear pump with two rotor shafts which are accommodated in a hydraulic block. The rotor shafts are mounted in a gear housing on one side of the hydraulic block and in a cylinder housing of a piston cylinder unit which bears on an other side of the hydraulic block. This gear pump uses an extremely simple construction manner and simultaneously achieves a high delivery volume. The high delivery volume leads to an extremely low loading of the battery, by which its operational duration is increased.

Split torque gearbox with pivoted engine support

Abstract: A powerplant system for a vehicle such as a hybrid UAV includes a miniature gas turbine engine and a gearbox assembly. The engine is mounted to the gearbox assembly through a support structure which provides for pivotal movement of the engine relative thereto. The input gear is engaged with two gears such that the pivoted engine arrangement permits the input gear to float until gear loads between the input gear and the first and second gear are balanced. Regardless of the gear teeth errors or gearbox shaft misalignments the input gear will float and split the torque between the two gears.

External gear pump with pressure fluid pre-loading

Abstract: External gear pump, comprising: a casing ( 3 a, 3 b ) with a gear chamber ( 4 ), comprising an inlet ( 5 ) for a fluid on a low pressure side and an outlet ( 6 ) on a high pressure side and comprising axial and radial sealing stays ( 7, 8 ); toothed wheels ( 1, 2 ) being in toothed mesh, wherein the external toothings of the wheels ( 1, 2 ) form delivery cells ( 10 ) for the fluid which are axially sealed off by the axial sealing stays ( 7 ) and radially sealed off by the radial sealing stays ( 8 ); and at least one pressure fluid supply ( 15, 16 ) through which pressure fluid may be supplied to the low pressure side, wherein the at least one pressure fluid supply ( 15, 16 ) opens on the low pressure side into a delivery cell ( 10 ) which is radially opposed by one of the radial sealing stays ( 8 ).

Gear pump for supplying oil to vehicle IC engine incorporates dry sump pump with gearwheel driven by same shaft which drives main pump

Abstract: The gear pump for supplying oil to a vehicle IC engine incorporates a dry sump pump (32). This has a gearwheel (38) which is driven by the same shaft (12) which drives the main pump by a gearwheel (14) meshing with a second gearwheel (16) on a driven shaft (18).

Electro-hydrostatic actuator with a failsafe system

Abstract: An electro-hydrostatic actuator unit that contains a sealed pressurized housing filled with a dielectric fluid. A bi-directional motor is immersed in the fluid and drives a gear pump for exchanging fluid via a control circuit between the chambers of a bi-directional hydraulic actuator in response to an input from a controller. The chambers are separated by a piston and a piston rod is connected to an external load such as a plunger type valve. A failsafe circuit is also provided which is arranged to override the control circuit in the event a failsafe condition is detected by the unit controller. The failsafe circuit contains a motor driven pump that provides high pressure fluid from the pressurized reservoir to an accumulator. Valves are arranged to shut down the control circuit and deliver fluid from the accumulator to one of the cylinder chambers to rapidly move the actuator to a desired failsafe position. Both motor drive pumps, the actuator, cylinder, and the controller are fully immersed in the fluid reservoir.

All hydraulic crane mounted on cross-country vehicle

Abstract: The utility model relates to an all hydraulic crane mounted on a cross-country vehicle which belongs to crane machinery. The utility model is characterized in that an integral type driving cab, vehicle chassis drive axle six wheels drive and an engine with upper and lower separated type dual configuration are adopted, a heating and a refrigeration facilities and an independent hydraulic operation system are arranged in an upper vehicle driving cab, and an adjustable chair is arranged in the driving cab. The integral type driving cab which is adopted by the utility model leads driver's view field to be wider and ensures safe running and comfortable operation. The vehicle chassis drive axle six wheels drive leads the performance of the cross-country vehicle to be improved and is particularly suitable for oil fields, topographic low areas and marshy areas. When the chassis trouble occurs, the engine with upper and lower separated type dual configuration are adopted, so the upper vehicle can be normally used still. When the engine of the upper vehicle trouble occurs, a gear pump is driven by a lower vehicle of the engine by a gear box and a force taking device, so the hoisting operation can be completed by transferring power to an upper vehicle hydraulic system by hydraulic oil. In addition, the upper and the lower vehicles can mutually assist in the operation of the hydraulic operation system, and 70% energy and the maintenance cost can be saved.

Development of a quieter variable-displacement vane pump for automotive hydraulic power steering system

Abstract: In an automotive hydraulic power steering system a variable-displacement vane pump that is equipped with a control device for adjusting the eccentricity of the cam ring and thus pump delivery flow rate according to the pump rotational speed (i.e. vehicle speed) is gradually being used for energy saving in place of a fixed-displacement vane pump. However, fluid-borne noise radiating into the passenger compartment has greatly increased following this replacement, and, therefore, countermeasures to reduce pump source flow ripple have been required more than anything else to further spread its usage. This paper reports on development research of a quieter (low fluid-borne noise level) varia-ble-displacement vane pump for HPS systems. First, it is indicated based on both experimental measurements and sim-ulation analysis of pump source flow ripple that the excessive increase of fluid-borne noise produced by existing varia-ble-displacement vane pumps equipped with a cylindrical cam ring is mainly caused by vane bounce occurring in the trapping sections near the bottom dead center, which is difficult to prevent when a conventional cylindrical (completely round profile) cam ring is used. Next, a new cam ring profile for preventing vane bounce called a “modified profile cam ring” is proposed and its effectiveness is examined by noise tests in the passenger compartment of a real car as well as measurements of pump source flow ripple in a bench test circuit. The proposed cam ring is found to be successful in reducing fluid-borne noise to at least the level of a fixed pump. The newly developed types of pumps have already been put into practice in several kinds of automobiles.

Extruder/gear pump assembly

Abstract: The invention concerns an extruder/gear pump assembly (10) comprising an extruder screw (20) connected to the gear pump (14) The invention is characterized in that the relative speed of the extruder screw (20) and of the gear pump (14) is adjustable by means of a shaft (64) housed in the cavity of the extruder screw (20)

Arrangement for driving coolant pump for internal combustion engine has planetary gear components, coupling and brake structurally integrated into common housing

Abstract: The arrangement has a planetary gear arranged between the output of the crankshaft and the pump drive. The planetary gear can be operated by a coupling and brake so that the pump drive can be changed between two ratios and fully shut off. The planetary gear components (the planetary carrier (8), planetary wheels (9), sun wheel (10) and hollow wheel (7), the coupling (3) and the brake (4) are structurally integrated into a common housing (11).

Fuel pump drive system

Abstract: Disclosed is a fuel pump drive system which can change revolution ratio of an engine to a fuel pump to one-to-one without vast increase in cost, allowing the fuel pump to be smaller-sized fuel pump. The system has a conventional flywheel housing with a gear through hole opened to a gear train accommodation space and adapted to receive a conventional input gear as an element of a gear train for transmission of the torque to the fuel pump through meshing with an output gear with revolution ratio of the engine to the fuel pump being two-to-one, an air compressor gear (new input gear) for transmission of the torque to the fuel pump through meshing with a smaller main idle (output gear) via an idle gear within a range of the gear through hole with revolution ratio of the engine to the fuel pump being changed to one-to-one, and an adapter interposed between the flywheel housing and the fuel pump for rotatably supporting the idle gear in a position for meshing with the air compressor gear.

Vane pump wear sensor for predicted failure mode

Abstract: A vane pump is disclosed for use with gas turbine engines that is adapted and configured to provide a failure mode similar to that of a traditional gear pump. The vane pump includes a pump housing, a cam member, a cylindrical rotor member and a mechanism for communicating a high pressure fluid from the discharge arc region to the inlet arc region when the tip surface of each vane element has experienced a predetermined amounted of wear so as to prevent pump startup. The tip surface of each vane element wears as a result the sliding contact with the circumferential surface of the pumping cavity.

Variable capacity pump

Abstract: The casing (3) contains a gear pump with two wheels (1,2). These have adjustable engagement, to vary the quantity of fluid pumped from inlet (5) to outlet (6). A piston (8) coupled to at least one of the wheels, makes the adjustment. Piston chambers (9,10) are subjected to pressures (P9, P10), which act on the piston, through connections (11,12) with the high pressure side. A spring in the first piston chamber (9) acts on the piston, against fluid pressure (P9). A controller (15) adjusts the pressure in the second chamber (10), in accordance with a control magnitude (PR) which sets the rate of delivery.

Engine starter for remote-controlled model airplane

Abstract: An engine starter includes two motors housed inside a housing, a driven gear wheel meshed between the pinions at the motor shafts of the motors, a first idle gear meshed with an internal gear at the driven gear wheel, a second idle gear coupled to the first idle gear for synchronous rotation, an output gear wheel meshed with the second idle gear, and an output shaft axially extended from the output gear wheel and selectively provided with a socket or starting bar for starting the engine of any of a variety of model vehicles.

Drive device for vehicles

Abstract: PROBLEM TO BE SOLVED: To enable a driving mechanism having a high gear reduction ratio and a brake to be assembled in a compact housing of a drive device for vehicles. SOLUTION: This drive device 1 for vehicles comprises a wheel hub 3 supporting a vehicle wheel 2, a spur gear reducer 4 for reducing a rotational output of a motor and transmitting the output to the wheel hub 3, and a wet disk brake 7 for braking a rotation of the wheel hub 3. The spur gear reducer 4 comprises a pinion spur gear 41 connected to a motor shaft 10 and a large spur gear 42 engaged with the pinion spur gear 41. The wet disk brake 7 comprises a brake disk 71 and a pressure plate 72 and the wet disk brake 7 is installed inside the large spur gear 42. The pressure plate 72 reduces a rotation of the large spur gear 42 and brakes a rotation of the wheel hub 3 by depressing the brake disk 71 against a stopper 48 arranged at a flange part 46 of the large spur gear 42. COPYRIGHT: (C)2005,JPO&NCIPI

Double-axial seal compensating high pressure gear pump

Abstract: The utility model relates to an improvement for the floating side board(13) of the double axial sealing compensating gear pump. A radial pressure balancing groove(21) is arranged at the middle part near the edge of the side board; the balancing groove is internally provided with at least 4 high pressure recharging oil passing holes(20),(19). A positioning convex arc(32) is internally provided with two isolating grooves(31). The middle part of a 3-shaped sealing cushion(11) is connected with horizontal bars(11-1) which is embedded in the isolating grooves(31) so as to separate a pressing groove(24) into an I area in the middle and II areas at the two ends. A sealing baffle(9) is provided with bosses(9-1) same as that of the circumference at the isolating grooves(31). The utility model adopts the technical proposal of separating by areas so as to make the side board has little deformation, good stability, even abrasion and reduced leakage, realizing the more reliable axial sealing and radial sealing so as to improve the capacity efficiency and mechanical efficiency of the pump by 2 to 3 percent and prolong the service life of the gear pump.

Gear pump with gears having curved teeth and method of feeding elastomeric material

Abstract: A gear pump and method for pumping elastomeric material having two gears with meshing herringbone gear teeth. Each of the gear teeth has helical side portions and a curved central portion which extends circumferentially of the gear a distance equal to at least one half the pitch of the gear teeth to provide a continuous squeezing contact between the teeth of the two gears for pumping a uniform strip of elastomeric material from the gear pump.

Gearset, in particular for electric hand machine tools

Abstract: A gearset, in particular for electric hand machine tools, is disclosed, comprising a input toothed gear (12) sitting on and fixed to an input shaft (11) and an output toothed gear (13), engaging with the above which drives an output shaft (14). According to the invention, a smooth operation of the gearset and a longer service life as a result of a reduction in the mechanical loading of the teeth on start-up and on peak loading during operation may be achieved, whereby a spring elastic damping element (22) is arranged between the output toothed gear (13) and the output shaft (14).

Hydraulic system for a battery-operated industrial truck has two hydraulic pumps, the second pump being used for additional supply to a lifting mechanism

Abstract: Driven by a first electric motor (3), a first hydraulic pump (2) supplies a lifting drive mechanism and a subsidiary consumer Driven by a second electric motor (11), a second hydraulic pump (10) supplies a hydraulic steering device The second pump can be used for an additional supply to the lifting drive mechanism

Gear pump and liquid injection device

Abstract: PROBLEM TO BE SOLVED: To provide a gear pump and a liquid injection device using the gear pump, for increasing performance of the pump without the need for improving the accuracy. SOLUTION: In a gear pump, a drive gear and a driven gear 27 are housed in a housing chamber 23 disposed in a housing 21. The drive gear 26 is positioned by the contact with a side face of the housing chamber 23, and its drive shaft 22 is inserted and fixed in a shaft hole 35 of the housing chamber with clearance. The driven gear 27 is positioned by abutment on a side face of the housing chamber 23, and a driven shaft 30 is inserted and fixed into the driven gear 27, and is inserted and fixed into shaft support parts 29, 44 with clearance, which shaft support parts are formed to the housing 21 and a cover. COPYRIGHT: (C)2005,JPO&NCIPI