Showing papers on "Gear pump published in 2004"

Performance of a Magnetorheological Hydraulic Power Actuation System

Abstract: The performance of a magnetorheological (MR) hydraulic power system is analytically and experimentally assessed. Four MR valves are implemented as a Wheatstone bridge hydraulic power circuit to drive a hydraulic actuator using a gear pump. The compact hydraulic power actuation system is a Wheatstone bridge network driving a conventional hydraulic actuator. A key advantage of using MR valves in hydraulic actuation systems is that the valves have no moving parts. This reduces complexity and enhances durability compared to conventional mechanical valves. In such a system, an MR fluid is used as the hydraulic fluid. A constant volume pump is used to pressurize the MR fluid. If a change in direction is required, the flow through each of the valves in the Wheatstone bridge can be controlled smoothly via changing the applied magnetic field. A magnetic field analysis is conducted to design a high-efficiency compact MR valve. The behavior and performance of the MR valve is expressed in terms of nondimensional para...

Wheel creep control of hydraulic hybrid vehicle using regenerative braking

Abstract: A system according to this invention opposes creep in a hydraulic hybrid motor vehicle. An accumulator contains fluid at high pressure, and a reservoir contains fluid at lower pressure. An engine produces positive torque at the wheels during an engine idle condition, and a pump/motor, driveably connected to the wheels and the engine, has a variable volumetric displacement pumps fluid to the accumulator from the reservoir. A control system determines a magnitude of negative torque transmitted from the wheels to the pump/motor that would exceed the magnitude of positive torque, determines the volumetric displacement of the pump/motor corresponding to the magnitude of negative torque, changes the displacement of the pump/motor to the required displacement, and operates the pump/motor as a pump driven by negative torque from the wheels to pump fluid from the reservoir to the accumulator.

Integrated electric motor-driven oil pump for automatic transmissions in hybrid applications

Abstract: An electric motor is connected solidly to the main transmission oil pump shaft on the transmission case. An off-axis chain and gear are connected to the main oil pump shaft via a single freewheeling clutch, so that either source of torque in a hybrid motor can drive the oil pump or the oil pump can be driven by the electric motor or the hybrid motor depending on which motor is traveling at a higher speed.

Deadband regenerative braking control for hydraulic hybrid vehicle powertrain

Abstract: A system for braking the wheels of a hydraulic hybrid vehicle includes a brake pedal having a range of pedal displacement including a deadband displacement range, an accumulator containing fluid at relatively high pressure, a reservoir containing fluid at lower pressure, a pump/motor having variable volumetric displacement connected to the accumulator and reservoir, and driveably connected to the wheels; a system responsive to brake pedal displacement in the deadband range for placing the pump/motor in a pump state wherein the pump/motor is driven by the wheels and pumps fluid from the reservoir to the accumulator; and a control valve for changing the volumetric displacement of the pump/motor in response to displacement of the brake pedal.

Hydraulic supply device

Abstract: PROBLEM TO BE SOLVED: To provide a hydraulic supply device capable of setting driving torque of an electric oil pump in accordance with temperature of hydraulic fluid. SOLUTION: This hydraulic supply device 30 is composed of a driving source (an engine 2 and a motor generator 4) for letting a hybrid vehicle 1 run, a mechanical oil pump 20 driven by the driving source, an electric motor 22 driven by a 12V battery 24, the electric oil pump 21 driven by the electric motor 22, an automatic gear shift mechanism 7 for setting a change gear ratio by hydraulic fluid supplied from the mechanical oil pump 20 and the electric oil pump 21 and shifting gear for rotary driving force of the driving source to transmit it to a wheel 8, an oil temperature sensor 42 for detecting temperature of hydraulic fluid, and a control unit 15 for giving a command for pump driving torque to be outputted to the electric motor 22 as a torque command value to operate the electric motor 22. The control unit 15 decides a torque command value in accordance with oil temperature detected by the oil temperature sensor 42. COPYRIGHT: (C)2006,JPO&NCIPI

Using neural network theory to predict the properties of melt spun fibers

Abstract: Melt spinning is the most economically useful method for producing artificial fibers in the industry. Though the extruder screw speed, the gear pump gear speed, and the winder winding speed of the melt spinning system are the main factors affecting the tensile strength of as-spun fibers and the yarn count (denier), no mathematical model has been proposed to describe the cause and effect of these relations. In this paper, using neural network theory, we consider the extruder screw speed, gear pump gear speed, and winder winding speed of a melt spinning system as the inputs and the tensile strength and yam count of as-spun fibers as the outputs. The data from the experiments are used as learning information for the neural network to establish a reliable prediction model that can be applied to new projects, and the model's performance is verified.

Method of changing gears of automobile, automotive gear shifter, controller for automotive gear shifter, and actuator controller for automotive gear shifter

Abstract: To enable compactness by lowering the connecting force of dog clutch so as to decrease the energy consumption and reduce the size of a system. A method of changing gears of automobile which moves the dog clutch in the axial direction at the time of gear change, while applying weak periodic torque vibration between the gear of the dog clutch and change gear of the gear shifter, and disconnects the two gears and, after the gear of the dog clutch and change gear of the gear shifter have been disconnected, also moves the dog clutch in the axial direction, while applying weak periodic rotating speed vibration between the gear of the dog clutch and another change gear of the gear shifter, and connects the two gears.

Design and performance of gear pumps with a non-involute tooth profile:

Abstract: This paper describes the design and performance of external gear pumps with a tooth profile based on the cycloid tooth profile. A method has been developed to calculate accurately the displ...

Direct drive reciprocating pump

Abstract: The invention includes an apparatus for pumping a fluid through a reciprocating pump. Several motors are responsible for operating the pump assembly. Each of the motors has a drive shaft. The motor drive shafts are connected to a series of drive gears. The drive gears are operably connected to a single driven gear for rotating the driven gear. The single driven gear connects with the pump assembly and drives the reciprocating pump in order to force fluid through the reciprocating pump.

Dual-inlet gear pump with unequal flow capability

Abstract: A dual-inlet gear pump includes a drive gear and a driven gear. The invention utilizes the discovery that the drive gear will typically move a higher flow volume than does the driven gear, particularly when the fluid being moved is an air/oil mixture. The present invention takes advantage of this discovery to communicate a first higher expected flow source to the drive gear, and to separately communicate a second, relatively lower expected flow rate to the driven gear. A particular application is in a scavenging pump for a jet engine.

Internal gear pump and inner rotor of the pump

Abstract: Setting of the amount (e) of eccentricity between an inner rotor and an outer rotor of an internal gear pump has a degree of freedom, and this enables a discharge amount of the pump to be increased. A tooth bottom portion (4) of an inner rotor (1) is formed by a hypocycloid curve, an engagement portion (3) between the inner rotor and an outer rotor by an involute curve, and a tooth top portion (1) by an arbitrary curve such as a part of a circular arc or an ellipse, or an epicycloid curve.

Multistage gear pump

Abstract: A multistage gear pump for pressurizing fluid includes a housing, a drive shaft and a gear assembly. The drive shaft is rotatably supported in the housing. The gear assembly is disposed in the housing. The gear assembly includes at least first and second gear trains. Each train has a pair of drive and driven gears that are engaged with each other. The drive gear is provided on the drive shaft and followed by the driven gear. The first gear train and the second gear train are arranged so that fluid sequentially passes therethrough as the drive shaft rotates. A theoretical discharge capacity of the first gear train is larger than that of the second gear train.

Offset-drive magnetically driven gear-pump heads and gear pumps comprising same

Abstract: Magnetically driven gear-pump heads and pumps are disclosed. An exemplary gear-pump head includes a housing, a magnet cup, a pump driving gear, and a pump driven gear. The housing has a pump axis and defines a pump cavity. The magnet cup extends along the pump axis and contains a driven magnet that is rotatable inside the magnet cup about the pump axis. The driven magnet comprises a first driving gear. The pump driving gear has a first gear axis, and the pump driven gear has a second gear axis. The first gear axis is parallel to but laterally offset from the pump axis on a first side of the pump axis. The second gear axis is parallel to but laterally offset from the pump axis on a second side of the pump axis. The pump gears are situated in the pump cavity and interdigitate with each other such that rotation of the pump driving gear causes a corresponding contrarotation of the pump driven gear. The pump driving gear includes a second driving gear that interdigitates with the first driving gear such that rotation of the driven magnet causes, via the first and second driving gears, corresponding rotation of the pump driving gear and contrarotation of the pump driven gear to pump liquid through the pump housing.

Metering feeder, and system and method for kneading and extruding material

Abstract: A system for kneading and extruding a material includes a crusher for crushing the material into coarse particles, an extruder for conveying and extruding the material crushed by the crusher, a gear pump for receiving and discharging the material extruded from the extruder, and a kneading and extruding apparatus for kneading the material discharged from the gear pump and continuously extruding the kneaded material. Therefore, a material is accurately quantified and highly uniform, resulting in reduced product variations and ensured consistent quality.

Gear pump and liquid injection apparatus

Abstract: A gear pump includes a housing defining an accommodating chamber and a cover for sealing the accommodating chamber. The accommodating chamber accommodates a drive gear and a driven gear. Each of the drive gear and the driven gear includes an upper surface opposed to the cover and a lower surface opposed to the housing. An annular projection projects from the upper surface of the drive gear or the driven gear for contacting the seal plate. An annular projection projects from the lower surface of the drive gear or the driven gear for contacting the seal plate. The gear pump is capable of lowering the load when the drive gear and the driven gear are rotated.

Boat propulsion system

Abstract: A boat propulsion system interposed between a prime mover and a propeller shaft comprises a hydro-mechanical transmission including a hydrostatic transmission part and a gear transmission part. The hydrostatic transmission part includes a variable displacement hydraulic pump having a movable swash plate and a hydraulic motor fluidly connected to the hydraulic pump. The hydraulic pump is driven by the output rotary force of the prime mover. The gear transmission part is drivingly interposed between the hydrostatic transmission part and the propeller shaft so that the gear transmission part is driven by the input rotary force of the hydraulic pump with the assistance of the output rotary force of the hydraulic motor. A hydraulic clutch system may be interposed between the gear transmission part of the hydro-mechanical transmission and the propeller shaft so as to select one of opposite output rotary directions of the propeller shaft.

Wave gear drive with wide mesh three-dimensional tooth profile

Abstract: A wave gear drive in which wide-area meshing of the rigid internal gear and flexible external gear is achieved, reducing stresses on the bottom rim of the gear teeth and in the vicinity of the major axis of the inner ring surfaces of the wave generator, thereby improving the load capabilities of the wave gear drive.

Control system for continuous rubber molding apparatus

Abstract: A control system for continuous rubber molding apparatus comprising; a feed portion for feeding a rubber material previously removed of foreign substances or particles in the previous step; an extruder for kneading the fed rubber material and feeding forward the kneaded material; and a gear pump for delivering the rubber material, fed from the extruder, to a forming nozzle, the forming nozzle continuously extruding a rubber ribbon used for building a tire. The control system comprises: a pressure sensor for sensing a pressure in the gear pump; pressure comparator for comparing a sensed pressure and a set value; and motor controller for controlling the number of revolutions of a motor based on a comparison result given by the pressure comparator, the motor operative to drive a screw of the extruder.

Using Fuzzy Theory to Predict the Properties of a Melt Spinning System

Abstract: Though the extruder screw speed of melt spinning, the gear pump's gear speed, and the winder's winding speed are the major factors affecting the tensile strength of as-spun fibers and yarn count (denier), no mathematical model has been proposed to describe the cause and effect of these phenomena. In general, chemical fiber manufacturers often adjust such speeds according to their experience, which is both time consuming and uneconom ical. Moreover, once the input parameters are set, manufacturers rarely readjust them. Thus, it is difficult to satisfy the demand for product diversity in small quantities. In this paper, a mathematical model for calculating extruder screw speed, gear pump speed, and winder speed is proposed according to fuzzy theory to improve the quality of as-spun fibers and to make the process economically efficient.

Gear tooth and external gear pump

Abstract: The invention concerns a gear tooth (1) comprising a concave base (2) connected to its starting point at the root of the adjacent tooth and a top (3) connected to said base (2) via a first transition point (4). The invention is characterized in that the top of the tooth comprises two convex segments (7, 8) connected via a second transition point (9) causing a curve break in the tooth profile.

Medium-high pressure gear pump having asymmetric double-circular-arc gear shape

Abstract: The invention is a nonsymmetrical double-arc tooth form medium- and high- pressure gear pump, two gears on the driving shaft are staggered at half tooth form angle in circumferential direction, there is no baffle between the inside end face of the two gear pairs, there I a floating pressure side plate between outside end face and left-and-right end covers, and the gear top contacts and hermetically cooperates with the arc surface of the inner cavity in the pump case, where the driving shaft are connected with the two gears through keys, and the driven shaft is connected with a gear by key and the other is covered on the driven shaft, and the two engaging gear pairs can be helical cylindrical gears at equal helical angle and in opposite rotating direction. Its advantages: it can prolong the service life of gears, preventing oil leakage, implementing medium- and high- pressure transmission of the gear pump, the working pressure reaches above 6MPa and it reduces flow pulsating rate of the gear pump by 75% in comparison with involute gear pump, make the pump work more stably and the noise lower.

Automatic speed change box lubricant cleaning and replacing apparatus

Abstract: An automatic cleaning and replacing device used for gear-box oil includes that a solenoid valve used for switching the cleaning and replacing, the solenoid valve is arranged a port that is connected with a vehicle, and also connected with a gear pump and a strainer; the strainer used for removing impurity, which is connected with the solenoid valve, and has the port that is connected with the vehicle; a new oil tank used for containing new oil, which is connected with the gear pump; a waste oil tank used for containing waste oil, which is connected with the gear pump; a gear pump, which is connected with the new oil tank and the waste oil tank respectively, and connected with the solenoid valve. When the gear pump works, waste oil is exchanged by new oil at same quantity, and cycle and filtration is performed by the power of the vehicle gear box, so as to achieve the goal of cleaning.

Displacement vs Flow Control in IC Engines Lubricating Pumps

Abstract: Scope of this work is to analyse potentials in terms of efficiency of two pump units belonging to two families: the first intervening on the maximum volume generated by variable volume chambers (e.g. a vane pump where eccentricity is varied), the second that changes the quantity of fluid being sucked or delivered (e.g. a gear pump with variable timing). In more detail the comparison will be established between a vane pump where displacement is varied through eccentricity and an internal gear pump of Gerotor type where flow rate is controlled through a rotating sector that alters the effective geometry of kidney ports. A detailed simulation of the two solutions brings to evidence the advantages of the first approach with respect to the second as confirmed by experimental investigations.

An Investigation on the Performance of Hydrostatic Pumps Using Artificial Neural Network

Abstract: In this paper, an analysis of volumetric efficiency of hydrostatic pumps in a variety conditions is investigated by using a proposed neural network. The effects of the parameters, such as the number of revolution, hydraulic oil temperature and exit pressures, which act on performances of hydrostatic pumps like gear pumps, vane pumps, and axial reciprocal pumps with swash plate, on the volumetric efficiency have been examined. The revolution number of the pumps, exit pressure of the system and the hydraulic oil temperatures are greatly affected by the leakage flowrate. The neural network structure is very suitable for this kind of system. The network is capable of predicting the leakage flowrate of the experimental system. The network has a parallel structure and fast learning capacity. As it can be seen from the results for both approaches, neural network could be modeled hydrostatic pump systems in real time applications.

Extrusion molding system and method

Abstract: An extrustion molding system includes a die having a first opening with a unvariable shape and a second opening with a variable shape, an extruder which feeds resin to the die, and a gear pump arranged between the die and the extruder. An ECU conducts a first sequence control to change the shape of the second opening and a second sequence control to change the rotation speed of the first gear pump in synchronism with a change in the shape of the second opening.

Hydrokinetic torque converter for an automatic vehicle transmission

Abstract: A hydrokinetic torque converter assembly for use with a geared transmission in a vehicle powertrain. The transmission includes a gear pump with a pump driving member and the torque converter assembly includes an impeller shaft drivably engageable with the pump driving member. The impeller shaft and the pump driving member are configured to effect full driving engagement of the impeller shaft with the pump driving member as the torque converter is assembled with the geared transmission.

Rubber member molding equipment and rubber member molding method

Abstract: PROBLEM TO BE SOLVED: To provide rubber member molding equipment which, in twisting a rubber strip around a rotating support, can neither too much nor too less deliver the rubber strip at the start of the molding, and also to provide a rubber member molding method. SOLUTION: The equipment is equipped with a molding drum 7 around which the rubber strip S extruded through a molding mouthpiece 4 is twisted, a gear pump 3 which sends out the rubber material supplied from an extruder 2 to the molding mouthpiece 4, and a pressure sensor 11 which detects the outlet side pressure in the gear pump 3. A controlling device 8 performs the control so that the rotation of the molding drum 7 may be started after the gear pump 3 is driven for a predetermined time based on a point of time when the pressure, which the pressure sensor 11 detects after the start of the driving of the gear pump 3, has become a predetermined pressure or higher. COPYRIGHT: (C)2006,JPO&NCIPI

Foundation drilling apparatus and method with continuously variable hydraulic differential rotary table

Abstract: A drilling machine drills foundation holes known as drilled shafts or bored piles with a drilling tool attached to an end of a kelly. The kelly is rotated with a rotary drive. The rotary drive has a first motor, a final drive gear coupled to the kelly so as to rotate with the kelly and a planetary gear set between the first motor and the final drive gear. A second motor is coupled to the ring gear on the planetary gear set. A clutch can also be connected to the ring gear. The rotary drive allows the drilling tool to be rotated at low drilling speeds and, without stopping rotation or shifting gears, removed from the hole and accelerated to high speeds to discharge spoil. A mid-range is also possible, wherein the drilling tool can process fluids in the hole. Another motor and planetary gear set can be coupled to the final drive gear and to the second motor.

Torque dividing gear drive system and method of driving an output gear

Abstract: A torque dividing gear drive system, a method of driving and output gear, and a method of evenly dividing an output torque between three3 gears is provided. The torque dividing gear drive system that is provided has a first gear driven by an engine, a second gear coupled to the first gear, a third gear coupled to the first gear, a fourth gear coupled to the first gear, a fifth gear driven by the second gear, a sixth gear driven by the third gear, a seventh gear driven by the fourth gear, and an eighth gear driven by the fifth, sixth and seventh gears. The first gear may be a floating gear. A method of operating such system is also provided.