Showing papers on "Gear pump published in 2008"

Gear pump and foam dispenser

Abstract: A gear pump (26) for mixing first and second components includes an inlet port (48), a premix chamber (40), and a second component valve (80). The premix chamber (40) has a first end communicating with the inlet port (48), and a second end communicating with a source (28) of the first component through a valve (42), thus providing a fluid path to carry the first component through the inlet port upon operation of the gear pump. The second component valve (80) regulates fluid communication between a source of the second component and the premix chamber (40). Upon operation of the gear pump, the first component is drawn from its source (28) into the premix chamber (40), the second component is drawn from its source, through the second component valve (80), and into the premix chamber, and a premix of the first and second components is fed from the premix chamber through said inlet port (48).

Oil pump system for vehicle

Abstract: An oil pump system for a vehicle includes: a vane pump having a plurality of vanes which respectively project retractably from a plurality of vane accommodating grooves provided in a rotor so as to be brought into sliding contact with a cam surface, the vane pump being adapted to supply a hydraulic fluid to an automatic transmission; an electric power-driven oil pump for assisting the hydraulic pressure of the hydraulic fluid during an idling stop of the automobile; and an ECU for controlling its operation. During an idling stop, the hydraulic fluid is fed to the automatic transmission by the operation of the electric power-driven oil pump to assist the hydraulic pressure, while the hydraulic fluid is fed with pressure also to the vane accommodating grooves to press the vanes against the cam surface.

Optimization of relevant design parameters of external gear pumps

Abstract: This paper describes a numerical procedure for the analysis and the optimization of external gear pumps. The Fluid Power group of the University of Parma has implemented a numerical code for the simulation of external gear pumps and motors; the code is named HYGESim and it is based on a lumped parameter approach implemented in AMESim, writing proper submodels in C language. This work is focused on the optimization of the pump design with particular reference to the geometry of the recesses machined on the bushings. The procedure is based on a path search method known as Steepest Descent and optimizes the considered parameters starting from a design taken as initial reference. The objective functions defined for the optimization permit to account for the volumetric efficiency, the delivery pressure ripple, the maximum and minimum pressure peaks during the meshing process. An optimal design of the recesses has been proposed and a prototype of a pump, equipped with the proposed geometry of bearing blocks, was tested. Measured data and the comparisons with the experimental results obtained for the stock pump taken as reference are presented in the paper, confirming the potentials of the developed optimization methodology.

Manufacture and Use of Parallel Eccentric Electro-Mechanical Actuator

Abstract: A parallel eccentric electro-mechanical actuator provides motive power and includes an electric prime mover that drives the reducer's pinion gear. This pinion drives minimum three star gears with stationary shaft bearings. Each shaft contains an eccentric which are completely in parallel with each other. These eccentrics can be thought of as parallel/in-phase driven crankshafts. Each eccentric drives the parallel eccentric (PE) gear through a bearing. The PE gear exhibits a circular motion (without rotation) which in itself is unbalanced. The crankshafts have another eccentric which create an opposite inertia force to balance that of the PE gear. The PE gear contains an external toothed gear on its periphery. It meshes with the internal teeth of the output ring gear. The relative motion between the PE gear and the ring gear is that the PE gear rolls inside the ring gear. This relative motion is called hypo-cycloidal motion.

Power regenerating mechanism of hydraulic working machine

Abstract: The present invention relates to a power regeneration mechanism for a hydraulic work machine, which makes it possible to stabilize power regeneration and improve the efficiency of power regeneration. A hydraulic pump that discharges pressure oil, an engine that drives the hydraulic pump, a variable displacement pump motor that drives the hydraulic pump, an output shaft of an engine, and a pump motor. A pump drive 15 that is connected to the output shaft 14a, distributes the power of the engine 13 and the power of the pump motor 14 and transmits the power to the hydraulic pump 12, and a hydraulic actuator for a boom to which pressure oil discharged from the hydraulic pump 12 is supplied 6 and an accumulator 16 that accumulates the pressure oil discharged from the boom hydraulic actuator 6 when the boom is lowered via the pump motor 14. [Selection] Figure 1

A brushless motor drive with sensorless control for commercial vehicle hydraulic pumps

Abstract: The paper describes the electronic design of a brushless motor drive powering a hydraulic Motor-Pump-Unit (MPU) for automotive applications. The full MPU consists of a Permanent Magnet (PM) brushless motor, a three-phase MOSFET inverter with digital control and a gear pump for the hydraulic circuit. The MPU designed in this project is characterized by low voltage supply and high hydraulic output power, so that the choice of power electronic components have been particularly challenging, mainly because of conflicting requirements in terms of current rating and total cost. The experimental results obtained with a first MPU prototype demonstrate that the weak point of the complete mechatronic design is related to the volumetric efficiency of the gear pump, while the power converter and brushless motor assembly is characterized by an acceptable efficiency.

Multi-Drive Fluid Pump

Abstract: A multi-drive pump may include a pump housing, an inlet port, an outlet port, a primary pump gear, a secondary pump gear, a first internal mechanical drive mechanism coupled to the primary pump gear and a second internal mechanical drive mechanism and an internal electro-magnetic drive mechanism coupled to the secondary pump gear. The pump housing may define an internal volume fluidly coupled to the inlet port and the outlet port. The primary pump gear and the secondary pump gear may be positioned in the pump housing and coupled to one another. Rotation of the primary pump gear and the secondary pump gear draws fluid into the inlet port and expels fluid from the outlet port. The primary pump gear may be rotated by the first internal mechanical drive mechanism and the secondary pump gear may be rotated by the second internal mechanical drive mechanism and the internal electro-magnetic drive mechanism.

Hydraulic drive, in particular of an excavator, in particular for a slewing gear

Abstract: The present invention relates to a hydraulic drive, in particular of an excavator, in particular for a slewing gear with a hydraulic circuit, which includes a pump and an engine, wherein a high pressure store is provided which can be connected to the pump and/or to the engine via at least one valve and a controller is provided which controls the at least one valve.

Gear pump cavitation reduction

Abstract: A gear pump for operating with reduced likelihood of cavitation occurrences in the fluid being pumped thereby, the pump having a pair of gears each supported on a corresponding one of a pair of gear with teeth provided in each gear that mesh with at least one tooth of the other when such teeth have been rotated into a meshing region in the gear plane, and with one of the gear shafts being rotatably connectable to a motor. Bearing structures rotatably support corresponding ones of each of the pair of gear shafts with the bearing structures having bearing surfaces adjacent those gear sides. A pressurized fluid passageway is provided in at least one of the bearing structures across from the meshing region and extending between surface openings at the bearing surface of that bearing structure that are positioned on opposite sides of an alignment axis in that bearing surface, the surface openings being separated from one another by at least the width of a tooth provided in the pair of gears.

Mechanical-hydraulic combined transmission device

Abstract: A mechanical-hydraulic combined transmission device including an engine, a transmission, a planetary gear set, a variable capacity pump, a hydraulic motor and a decelerator. The engine drives the transmission and in turn drives the planetary gear set. The planetary gear set is configured to distribute the power from the engine to the variable capacity pump and a ring gear of the planetary gear set respectively. The variable capacity pump drives the hydraulic motor and in turn drives a half shaft. The hydraulic power flow from the hydraulic motor and the mechanical power flow from the ring gear are combined together and output by the half shaft. The half shaft drives the decelerator and in turn drives a rare axle. A special vehicle which adopts the technique according to the invention is provided with a single engine, it may run continuously variably in a mechanical-hydraulic combined transmitting way, and simultaneously drive the onboard special machine to work in a mechanical way. Mechanical transmitting mode will be chosen when the vehicle moves to another place, so high speed may be achieved.

Oil pump arrangement for internal-combustion engine, has oil pump that is actuated such that drive finger extends into drive groove formed in double clutch or drive finger extends into drive groove formed at drive wheel

Abstract: The arrangement has an oil pump (18) e.g. gear pump, arranged within a double clutch transmission (1). The oil pump is actuated such that a drive finger is provided at a drive wheel for the oil pump and extends into a drive groove formed in the double clutch or the drive finger is provided at the double clutch and extends into a drive groove formed at the drive wheel. The transmission has a transmission housing (2) with a double clutch housing (3), where the oil pump is arranged within the double clutch housing.

Variable displacement type gear pump

Abstract: A variable displacement type gear pump has gear chambers, one of which is a specific gear chamber. A suction passage (35,36,37) is formed in the housing so as to communicate with suction-side spaces (31,33). An outlet passage (41) communicates with discharge-side spaces (32,34). A return passage (50) returns the fluid discharged to the discharge-side space of the specific gear chamber to the suction passage. The return passage communicates with the suction passage at a confluence portion located upstream side of the suction-side space. An opening and closing valve (51) opens the return passage in a small displacement operational state. A check valve (45) is located between the discharge-side space of the specific gear chamber and the outlet passage for preventing the fluid discharged from the gear chamber other than the specific gear chamber from flowing into the discharge-side space of the specific gear chamber in the small displacement operational state.

Bearing tooth gears for wind turbine applications

Abstract: A horizontal axis wind turbine includes a vertically extending tower (117) having a rotatable long shaft (121). A bottom end of the long shaft drives an electric generator (122) and a top end of the long shaft is connected to a power output gear assembly of a bearing tooth angle drive (120). The power output gear assembly is engaged with a power input gear in the bearing tooth angle drive (120). The power input gear is connected by a drive shaft (86) through a preferably planetary gear drive (119) to blades (106) of a wind turbine to receive power from the wind turbine and to deliver torque to the long shaft (121) to drive the generator (122). The planetary gear teeth preferably have flat surfaces providing contact with related gear teeth.

Drive train for motor vehicle, has control device controlling pump motor of auxiliary hydraulic pump such that pump is switched ON only if actual hydraulic oil requirement of transmission is not provided by main hydraulic pump

Abstract: The train has a main hydraulic pump (7) i.e. mechanically driven pump, and an auxiliary hydraulic pump (9) i.e. electric-motor driven pump, that are attached to a transmission (3). A control device (11) controls a pump motor (10) of the auxiliary hydraulic pump such that the auxiliary hydraulic pump is switched ON only if the actual hydraulic oil requirement of transmission is not provided by the main hydraulic pump, if hydraulic oil temperature is lesser than appropriate threshold value and if trailing switching-on period of auxiliary hydraulic pump is lesser than appropriate threshold value.

Power system of jump robot

Abstract: The invention discloses a power system of the jumping robot. A brushless direct current motor is connected with a gear pump, the oil-in of the gear pump is connected with the oil tank, and the oil outlet of the gear pump is connected with the port A of the two-position four-way solenoid directional control valve. The port B of the two-position four-way solenoid directional control valve is connected with the inner of the gasoline tank. The port P of the two-position four-way solenoid directional control valve is connected with the upper chamber port of the hydraulic cylinder, and the port T of the solenoid directional control valve is connected with the lower chamber port of the hydraulic cylinder; wherein, a spring is arranged in the upper chamber of the hydraulic cylinder, one end of the spring is propped on the upper inner wall of the hydraulic cylinder, and the other end of the spring is propped on the upper wall of the piston of the hydraulic cylinder. The power system of the jumping robot has the advantages that the power of motor of the system is reduced; the element amount of the system is reduced; meanwhile the weight of the brushless direct current motor is only one-third of the brush motor with the same power, the jumping energy is cumulated and stored, and the total weight and volume of the system is reduced. The invention is suitable for using in the jumping robot.

Hydraulic system for tunneling machine

Abstract: The invention relates to a development machine hydraulic system, belonging to an open type hydraulic system. The invention is characterized in that: a constant power loading sensitive axial plunger variable displacement pump provided with pressure cut-off function is connected with a six-way proportional multichannel conversion valve with functions of pressure compensation and load sensing through a pipe; various plate valves are arranged inside the six-way proportional mutlichannel conversion valve and respectively connected with and control various actuators; pressure compensation valves are respectively connected on oil inlet pipes of various plate valves and used for adjusting flow values of various plate valves; a pilot opening of the proportional multichannel valve is connected with a manual proportional pilot valve. The whole system has the function of power adaptation and solves the problems of gross leak, large power loss, low pressure, high temperature rise of oils and low reliability of a hydraulic system consisting of a gear pump and a manual multiple-way valve. The invention has the advantages of improvement of power/weight ratio of the hydraulic system, more comfortable and safer operation of drivers due to a proportional pilot handle, more precise action and great improvement of reliability.

Aircraft landing gear

Abstract: The invention relates to an aircraft landing gear comprising a landing gear leg, wherein the landing gear leg or one or more parts of the landing gear leg consists partly or completely of a fiber composite material.

Internal gear pump

Abstract: The utility model discloses an internal gear pump which comprises a pump body, a front end cover, a rear end cover, and an internal gear pair consisting of an internal tooth ring and a pinion, wherein a radial clearance floating compensation device dividing a space into a high pressure chamber and a low pressure chamber is arranged between the pinion and the internal tooth ring; side plates are respectively arranged on the two sides of the internal gear pair; grooves and sealing rings around the grooves are formed in and arranged on the contact surfaces between the side plates and the corresponding front end cover and rear end cover; and channels positioned in areas defined by the sealing rings are formed in the side plates to form a pressure chamber communicated with the high pressure chamber. The internal gear pump is characterized in that the channel in one of the two side plates is matched with an oil outlet channel to form a high pressure flow channel; and the internal oil port of the oil outlet channel is exposed out of the pressure chamber in which the high pressure flow channel is located. The internal gear pump ingeniously utilizes the sealing rings at the original pressure chamber, so that high pressure oil is free from leakage in a spill process, a zero-clearance butting oil outlet mode of the high pressure flow channel is realized, and the volumetric efficiency of the internal gear pump is further improved.

Gear pump using water as pressure medium

Abstract: A gear pump adopting water as hydraulic medium relates to a hydraulic gear pump. The invention solves the problems of the prior hydraulic pressure plunger pump such as a complex structure, difficult processing and assembling, high wear rate, high cost, low floor area ratio, short service life and poor antipollution capacity and is only suitable to be used under high-pressure conditions. The invention adopts the following structure: the front sides and the back sides of a driving gear (7-1) of a driving gear shaft (7) and a driven gear (13-1) of a driven gear shaft (13) are provided with side plates (6); the end faces of the side plates (6) with the back towards the driving gear (7-1) and the driven gear (13-1) are provided with floating shaft sleeves (5); sliding bearings (12) are respectively arranged among the floating shaft sleeves (5), the side plates (6) and the driving shaft (7-2) of the driving gear shaft (7), as well as among the floating shaft sleeves (5), the side plates (6) and a driven shaft (13-2) of the driven gear shaft (13). The development of the gear pump is the complement of a hydraulic pressure element and is of great significance to speed up the development of the hydraulic pressure transmission technical field, enlarge the application scope of hydraulic pressure transmission and realize the technology which replaces oil pressure transmission by hydraulic pressure transmission.

Electric pump unit and electric oil pump apparatus

Abstract: In an electric pump unit, communication between arcuate ports provided in correspondence with a discharge side and a suction side of an internal gear pump is selectively permitted and prohibited in correspondence with movement of a spool of a relief valve. If fluid pressure at the discharge side of the internal gear pump becomes greater than or equal to a predetermined value, the spool moves across an inner arc of one of the arcuate ports corresponding to the suction side of the internal gear pump and from a position at which the spool prohibits the communication between the arcuate ports to a position at which the spool permits the communication. As the spool moves away from the position at which the spool blocks the communication between the arcuate ports, the opening degree of the relief valve changes in accordance with a downward convex curve.

A study on the structureborne noise of hydraulic gear pumps

Abstract: The main source of vibration and noise in hydraulic systems is the flow ripple at the pump output which interacts with the downstream components and generates pressure ripple in the current, structureborne noise in mechanical parts and airborne noise in the environment. The present research was suggested by the observation that some peaks in the airborne noise spectrum of a specific pump family were within a frequency range far from those typically related with the fluidborne or structureborne noise; unfortunately, in that range the human ear does not filter the noise efficiently. In general, the investigation of the interaction between fluidborne noise and structurebornenoise can be carried through both “macro-analysis” techniques (sound emission analysis, pressure ripple measurement, modal analysis, etc.) and “micro-analysis” techniques (contact mechanics of gears, performance of the bearing system, etc.). The present research started from a “macro” approach inclusive of the modal analysis of a gear pump, the measurement of its pressure ripple and its acoustic mapping though the sound intensity technique. Currently, the focus is on the “micro” approach and specially on the investigation of the elasto-hydrodynamic bearing performance in view of deriving the influence of the bearing geometry on the overall structureborne noise.

Rotary gear pump for use with non-lubricating fluids

Abstract: An improved external rotary gear pump for use with non-lubricating fluids such as amine is disclosed. The device uses specially coated internal parts chosen to reduce friction and improve wear characteristics so that the resulting pump will operate for a minimum warranty period of one year.

Fully automatic hydraulic pressure and reverse rotation prevention device

Abstract: A full-automatic hydraulic anti-inversion device comprises a tank body and a transmission shaft whose lower part is arranged in the tank body. The transmission shaft is provided with a pulley and a break disk. The inner of the tank body is provided with a bidirectional gear pump and the transmission gear of the gear pump is coupled with the main transmission gear of the transmission shaft. The oil outlet hole of the bidirectional gear pump comprises a lubricating circuit which is composed by the respective connection of an oil tank, an oil filter, an one-way valve and a lubricating passage, a breaking circuit which is composed by an oil tank, an oil filter, an one-way valve and a hydraulic passage for supplying oil to bearings. The hydraulic passage is provided with an overflow small hole and an oil tank which is connected with the overflow small hole. When the transmission shaft rotates forwards, the bidirectional gear pump supplies the hydraulic oil to the bearings to lubricate via the lubricating circuit. When the transmission shaft rotates backwards the bidirectional gear pump supplies the hydraulic oil to the break oil cylinder via the breaking circuit and the overflow small hole will exhaust the remainder oil to the oil tank. The character is that the locking phenomenon of the reversal of the ratchet wheel is avoided, the hidden danger which is brought by the fracture of the sucker rod and the sudden outburst of the storing energy is avoided.

Vehicle-mounted danger-avoiding device

Abstract: The utility model relates to an auxiliary braking device of a vehicle, in particular to a danger avoiding device of a vehicle. The auxiliary braking device includes the bottom plate of the vehicle and a gearbox, and also includes a fixing shaft, a holding plate, a hydraulic cylinder, an oil pipe, an operation handle, a multi-way valve, an oil box and a gear pump. One end of the holding plate arranged between the bottom plate of the vehicle and a wheel is fixed below the bottom plate of the vehicle by the fixing shaft and the other end is obliquely arranged below the bottom plate of the vehicle by the hydraulic cylinder. The lifting of the piston of the hydraulic cylinder can lead the holding plate to clutch the wheel; the multi-way valve arranged in a cab and provided with the operation handle is connected with the hydraulic cylinder by the oil pipe; the oil box arranged below the bottom plate of the vehicle is respectively connected with the gear pump of the gearbox and the multi-way valve by the oil pipe. The oil box and the multi-way valve are connected by the oil pipe to form a return oil loop. The gear pump and the multi-way valve are connected by the oil pipe to form a high pressure oil loop. The danger avoiding device of a vehicle can fast brake the vehicle, becomes an independent system, etc. The danger avoiding device of a vehicle is suitable for being applied on trucks in particular.

Pump assembly for synchronous pressurization of two fluid circuits

Abstract: The invention relates to a pump assembly for the synchronous pressurization of two fluid circuits. Two internal gear pumps are disposed together in a pump housing and rotationally driven by drive shafts thereof. Pinions of the pumps are located in an associated pump chamber and engage in an internal gear thereof. The pump chambers of the internal gear pumps are separated from each other by a common separating wall or partition, which is designed as a separate housing part and engages in a hollow cross-section of a housing part forming the circumferential wall of one of the internal gear pumps. Suction channels and pressure channels associated with the internal gear pumps transition into a radially extending longitudinal section in the pump housing following an axial longitudinal section in the lateral boundary wall of the associated pump chamber. According to the invention, a suction channel and a pressure channel of one of the internal gear pumps are integrated in the separating wall.

Motor and pump assembly having improved sealing characteristics

Abstract: The present invention comprehends a gerotor or gear pump driven by a permanent magnet motor which exhibits cogging torque, i.e., resistance to rotation when de-energized caused by interaction between permanent magnets in the rotor and teeth on the stator. Such interaction causes the rotor to come to rest in one of many defined rotational positions and resist rotation when electrical power to the motor has been terminated. The permanent magnet motor is coupled, preferably directly, to a gerotor pump having meshing rotors or a gear pump having meshing gears. When the motor is de-energized, the pump rotors or gears come to rest and their rotation is resisted by the cogging torque of the motor. The invention finds particular application in automotive transmissions and systems with parallel pumps.

High pressure gear ring pump internal tooth ring static pressure unloading device

Abstract: A static pressure unloading device for ring gears of high pressure internal gear pumps arranges a static pressure structure in an eccentric pump housing bore, uses static pressure to totally offset the positive pressure produced when the ring gear works under high pressure to the eccentric pump housing with tiny oil film clearance existing, avoiding adhesive wear and increasing working pressure. Further the static pressure oil film can generate damped vibration, reduce coefficient of friction and achieve the purpose of long service life, low noise and high efficiency.

Driving force distribution/transmission device

Abstract: A driving force distribution/transmission device in which uneven distribution of lubricant oil is minimized even in turning etc. of a vehicle. By this, a sliding portion is smoothly lubricated to enhance reliability of lubrication. The driving force distribution/transmission device (1) has a gear input rotation member (53) and a gear output rotation member (55) that are operatively linked with each other such that they can transmit driving force through meshing between a drive pinion gear (91) and a ring gear (93), and also has a left and right pair of clutch output adjustment mechanisms (57, 59) joined to opposite ends of the gear output rotation member (55) and performing driving force output adjustment by engagement of main clutches (139). The drive pinion gear (91) and the ring gear (93) are received in a gear chamber (56) sectioned in a sealed manner. The main clutches (139) are respectively received in a left and right pair of clutch chambers (125) sectioned in a sealed manner. Gear oil and clutch oil are respectively sealed in the gear chamber (56) and in lubrication spaces of three independent chambers of the left and right pair of clutch chambers (125).