Showing papers on "Gear pump published in 2010"

Lubrication and cooling of a reduction gear with epicyclic gear train

Abstract: The invention relates to a method for lubricating and cooling a reduction gear with epicyclic gear train, in particular in a turbomachine of an aircraft engine, including a cylindrical casing (52) mounted on the planet carrier (30) of the reduction gear and forming a centrifugal scoop surrounding the stationary oil-carrying ramps (56), said cylindrical casing (52) including radial conduits (62, 64, 66) supplying injectors (68) directed towards the areas where the planet gears (28) mesh with the outer crown or crowns (16, 20) of the reduction gear.

Analysis of Stress and Deformation in Plastic Gears Used in Gerotor Pumps

Abstract: The mechanism of induction of stresses and deformations in plastic cycloidal gears used in gerotor pumps has been analysed using the finite element method and the ABAQUS program. It has been found that the gear system remains under the influence of the mechanical load resulting from the torque on the pump shaft and the hydraulic load resulting from the activity of pressure in the intertooth displacement chambers. It has also been discovered that the intertooth forces and stresses are formed only in the part of the gear that can be referred to as ‘active’. In the other part of the gear, forces and stresses do not occur, and the part can be referred to as ‘passive’. Another finding of the research is that gear deformations occur such that the teeth of the external gear are deformed and moved in the direction of the active part of the mesh, and the teeth of the internal gear in the direction of the passive part. Thus, radial and axial intertooth clearances are formed, which result in internal leakages in the...

Hydraulic system having implement and steering flow sharing

Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a first pump with variable displacement and being load-sense controlled, and a first hydraulic circuit associated with the first pump. The hydraulic system may also have a second pump with variable displacement and being electro-hydraulically controlled, and a second hydraulic circuit associated with the second pump. The hydraulic system may further have a flow-sharing valve arrangement configured to selectively share fluid flow between the first and second hydraulic circuits.

Hydraulic performance of a large slanted axial‐flow pump

Abstract: Purpose – The pump of the Taipuhe Pump Station, larger flow discharge, lower head, is one of the largest 15° slanted axial‐flow pumps in the world. However, few studies have been done for the larger slanted axial‐flow pump on safe operation. The purpose of this paper is to analyze the impeller elevation, unsteady flow, hydraulic thrust and the zero‐head flow characteristics of the pump.Design/methodology/approach – The flow field in and through the pump was analyzed numerically during the initial stages of the pump design process, then the entire flow passage through the pump was analyzed to calculate the hydraulic thrust to prevent damage to the bearings and improve the operating stability. The zero‐head pump flow characteristics were analyzed to ensure that the pump will work reliably at much lower heads.Findings – The calculated results are in good agreement with experimental data for the pump elevation effects, the performance curve, pressure oscillations, hydraulic thrust and zero‐head performance.Re...

A hybrid propulsion system for a motor vehicle with a double-drum gear control device

Abstract: The hybrid propulsion system (10) comprises a combustion engine (12), a gearbox (16), and an electric machine (20) kinematically connected to the gearbox (16) by means of a first drive transmission mechanism (22) comprising a pinion (74) carried by an output shaft (72) of the electric machine (20), one (44) of the gears of the gearbox (16) and an intermediate gear (76). The gearbox (16) comprises a gear control device (80, 82) and first and second shafts (28, 30) on which are mounted a plurality of idle gears (46, 48, 50, 52, 60, 62, 64) and a plurality of slidable engagement sleeves (54, 56, 68, 70) each of which is associated with one or two idle gears to connect them for rotation with the respective first or second shaft (28, 30). The gear control device (80, 82) comprises a first drum control device (80) associated with the first shaft (28) to control the movement of the slidable engagement sleeves (54, 56) disposed on that shaft, a second drum control device (82) associated with the second shaft (30) to control the movement of the slidable engagement sleeves (68, 70) disposed on that shaft, and an actuation unit (116, 122) which is arranged to bring about rotation of the first and second drum control devices (80, 82) in a synchronized manner. The actuation unit (116, 122) comprises a motor device (116) and a second drive transmission mechanism (122) in turn comprising a first gear (124) associated with the first drum control device (80), a second gear (126) associated with the second drum control device (82), and an intermediate gear (128), the first or second gear (124, 126) meshing with an output pinion (120) of the motor device (116) and the intermediate gear (128) meshing both with the first gear (124) and with the second gear (126). The intermediate gear (128) of the second drive transmission mechanism (122) is coaxial with the intermediate gear (76) of the first drive transmission mechanism (22).

Flow pumping system for physiological waveforms

Abstract: A pulsatile flow pumping system is developed to replicate flow waveforms with reasonable accuracy for experiments simulating physiological blood flows at numerous points in the body. The system divides the task of flow waveform generation between two pumps: a gear pump generates the mean component and a piston pump generates the oscillatory component. The system is driven by two programmable servo controllers. The frequency response of the system is used to characterize its operation. The system has been successfully tested in vascular flow experiments where sinusoidal, carotid, and coronary flow waveforms are replicated.

Fluid pumping unit, particularly for medical area for use within body vessel, has fluid pump which consists of pump rotor and drive device for driving fluid pump, where drive device has fluid supply line and drive rotor driven by fluid

Abstract: The fluid pumping unit (4) has a fluid pump which consists of a pump rotor and a drive device for driving the fluid pump. The drive device has a fluid supply line and a drive rotor driven by a fluid. The drive rotor is connected with a shaft of the pump rotor directly or by a mechanical drive. A shaft of the drive rotor is rotatably connected with the shaft of the pump rotor.

Flowrate Formulation of Deviation Function Based Gerotor Pumps

Abstract: This paper derives formulas for evaluating the flowrate of gerotor pumps. The flowrate formulas are based on a deviation function, and the pitch and generating curves can be circular or noncircular. Two dimensionless parameters, the lobe noncircularity and the pitch noncircularity, are introduced so that gerotor performance can be analyzed systematically.

Exhaust heat recovery system

Abstract: PROBLEM TO BE SOLVED: To provide an exhaust heat recovery system capable of reducing operation drag by a pump when a compression mechanism is driven by a rotary electric machine without extending a compound fluid machine in an axial direction. SOLUTION: A vehicular exhaust heat recovery system 11 includes a compound fluid machine 40 having a compression mechanism 60, an expansion mechanism 85, a gear pump 75, a motor generator 50 disposed on a same shaft. In the compound fluid machine 40, the gear pump 75 is driven at the same time when the compression mechanism 60 is driven by the motor generator 50. In Rankine cycle 20, a first channel 21a connecting a pump chamber of the gear pump 75 and a boiler 26, and a second channel 21b connecting the pump chamber of the gear pump 75 and a condenser 23 are connected by a bypass channel 28. A bypass valve 28a is disposed at the bypass channel 28. COPYRIGHT: (C)2011,JPO&INPIT

Modelling and simulation of a dual-clutch transmission vehicle to analyse the effect of pump selection on fuel economy

Abstract: Positive displacement pumps are used in automotive transmissions to provide pressurised fluid to various hydraulic components in the transmission and also lubricate the mechanical components. The output flow of these pumps increases with pump/transmission speed, almost linearly, but the transmission flow requirements often saturate at higher speeds, resulting in excess flow capacity that must be wasted by allowing it to drain back to the sump. This represents a parasitic loss in the transmission leading to a loss in fuel economy. To overcome this issue, variable displacement pumps have been used in the transmission, where the output flow can be reduced by controlling the displacement of the pump. The use of these pumps in automatic transmissions has resulted in better fuel economy as compared with some types of fixed displacement pumps. However, the literature does not fully explore the benefits of variable displacement pumps to a specific type of transmission namely, dual-clutch transmission (DCT), which has different pressure and flow requirements from an epicyclic gear train. This paper presents an analysis of the effect of pump selection on fuel economy in a five-speed DCT of a commercial vehicle. Models of the engine, transmission, and vehicle are developed along with the models of two different types of pumps: a fixed displacement gerotor pump and a variable displacement vane pump. The models are then parameterised using experimental data, and the fuel economy of the vehicle is simulated on a standard driving cycle. The results suggest that the fuel economy benefit obtained by the use of the variable displacement pump in DCTs is comparable to the benefit previously shown for these pumps in automatic transmissions.

Variable lubricant level in a differential sump

Abstract: A system for lubricating a differential mechanism includes a housing containing a ring gear, a pinion meshing with the ring gear, a sump containing fluid, and a reservoir that receives fluid flung from the ring gear as the ring gear rotates through the sump fluid, and an orifice restricting the flow rate of fluid from the reservoir.

Micro gear pump with internal electromagnetic drive

Abstract: This paper presents the concept, design and fabrication of a gear pump based on recently introduced synchronous micro motors as an integrated driving system. The micro motor is fully integrated in the fluidic system consisting of the inlet, outlet and pump chamber. A preliminary test on the gear pump flow rate is successfully reported. The whole system is mainly realized by means of micro fabrication technologies like UV-depth lithography and copper electroplating. Polymer magnets with alternating axial magnetization were applied in the toothed rotors. The use of polymer magnets affords a miniaturization with maximum space filling and without limitation in shape. In first tests the temperature behavior and the functional capability were investigated.

Aircraft main engine fuel pump with multiple gear stages using shared journals

Abstract: A multistage gear pump assembly (120) includes first and second gear pumps (140a, 140b) that use common shafts and are axially separated by a spacer plate (170) secured within a common bore (130) and secured to the housing (122). Pressurized bearings are provided at opposite axial ends of the first and second gear pumps. The second gear pump handles cruise and idle operations of the aircraft while the first gear pump stage assists in meeting higher demand modes of engine operation. Otherwise, the first gear pump is maintained at a minimal pressure to reduce energy consumption and still provide desired stability and eliminate issues associated with bearing oil whirl associated with prior known arrangements. However, when additional assistance is required, such as during takeoff, climb, or windmill relight, the first gear pump advantageously contributes to the increased pressure.

Automatic dual-clutch transmission

Abstract: In an automatic dual-clutch transmission, a lowest speed driven gear, other driven gears and a reverse gear are provided on a first output shaft to be freely rotatable. A 2nd speed driven gear and a highest speed driven gear are provided on a second output shaft to be freely rotatable. Further, the 2nd speed driven gear is provided with a large-diameter gear meshing with a 2nd speed drive gear and a small-diameter gear provided bodily with the large-diameter gear, being fewer in tooth number and smaller in diameter than the large-diameter gear, and meshing with the reverse gear. Thus, the automatic dual-clutch transmission is reduced in diameter by not having an output shaft dedicated to the reverse gear and is able to set the gear ratio for reverse to be large.

Wind turbine generator or tidal current generator and operation method thereof

Abstract: An object of the invention is to provide a wind turbine generator or a tidal current generator which is equipped with a hydraulic transmission and achieves a superior power generation efficiency, and a operation method thereof The wind turbine generator 1 comprises a hydraulic pump 12 of a variable displacement type which is rotated by the main shaft 8, a hydraulic motor 14 of a variable displacement type which is connected to the generator 20, and a high pressure oil line 16 and a low pressure oil line 18 which are arranged between the hydraulic pump 12 and the hydraulic motor 14 The pump controller 32 obtains a target torque of the hydraulic pump 12 at which a power coefficient becomes maximum, and then sets a displacement Dp of the hydraulic pump 12 based on the target torque and the pressure in the high pressure oil line 16 The motor controller 34 sets a displacement Dm of the hydraulic pump 14 based on a discharge amount Qp of the hydraulic pump obtained from the displacement Dp of the hydraulic pump 12 so that the rotation seed of the generator 20 becomes constant

Effect of Graphite and Carbon Nanofiber Additives on the Performance Efficiency of a Gear Pump Driven Hydraulic Circuit Using Ethanol

Abstract: We show that fine graphite flake and carbon nanofiber dispersed ethanol solutions can potentially replace conventional hydraulic fluids in gear pump-driven hydraulic circuits operating below I MPa gauge pressure. Low-viscosity hydraulic fluids are generally detrimental to pump life. However, both graphite and carbon nanofiber dispersions in ethanol within a concentration range of 195-1500 ppm can sustain hydraulic circuits with increases in pump efficiency and without modifying the viscosity of ethanol. Pump inlet pressure, volumetric flow rate, and electric power consumption data were recorded over a range of pump discharge pressures. Pump power consumption at a given differential pump pressure was found to remain approximately constant for all suspensions. However, increases in both volumetric flow rate and overall pump efficiency were observed when pure ethanol was replaced by the nanostructured carbon/ethanol solutions. The presence of the additives can partially or collectively improve a number of lubrication mechanisms which exist in a gear pump such as boundary, hydrodynamic, hydrostatic, elastohydrodynamic, and mixed-film lubrication. Additionally, we observed that the additives deposited permanently on gear and enclosure surfaces creating low shear strength films which can help reduce friction. Qualitative examination of environmental scanning electron microscope images of colloidal graphite and carbon nanofiber additive morphology before and after extended run periods indicated that graphite retained significant resilience, whereas carbon nanofibers appear to have undergone some scission.

Control device of microminiature turbojet and starting control method thereof

Abstract: The invention discloses a control device for a microminiature turbojet engine and a starting control method thereof. The device comprises a rotating speed sensor for collecting the rotating speed of an engine, a temperature sensor for collecting exhaust temperature, a switch controller, a throttle controller, an electronic control unit (ECU) and an executing mechanism, wherein the executing mechanism comprises a starting motor, a hot piston, a propane gas valve, a fuel protective valve and a fuel gear pump. The control method comprises the following steps: the ECU monitors the working state of the engine through the sensor, and outputs a pulse-width modulation signal to a power drive circuit to control the starting motor, the hot piston, the propane gas valve, the fuel protective valve and the fuel gear pump so as to complete starting control to the engine; functions of establishing fuel pressure and adjusting fuel quantity can be realized by the fuel gear pump after starting of the engine is completed; and fuel can be accurately supplied to ensure that the engine operates in an expected working state. The device can be used for a microminiature delivery vehicle, and the executingmechanism of the device has the advantages of simple structure, small volume and light weight, and easily realization of reliable and efficient control to the engine.

Modelling the effects of operating conditions on motor power consumption in single screw extrusion

Abstract: Extrusion is one of the most important production methods in the plastics industry and is involved in the production of a large number of plastics commodities. Being an energy intensive production method, process energy efficiency is of major concern and selection of the most energy efficient processing conditions is a key aim to reduce operating costs. Extruders consume energy through motor operation (i.e. drive to screw), the barrel heaters and also for cooling fans, cooling water pumps, gear pumps, screen pack changing devices etc. Typically the drive motor consumes more than one third of the total machine energy consumption. This study investigates the motor power consumption based on motor electrical variables (only for direct current (DC) motors) and new models are developed to predict the motor power consumption from easily measurable process settings for a particular machine geometry. Developed models are in good agreement with training and unseen data by representing the actual conditions with more than 95% accuracy. These models will help to determine the effects of individual process settings on the drive motor energy consumption and optimal motor energy efficient settings for single screw extruders.

Two-component spraying system

Abstract: The invention discloses a two-component spraying system which comprises a first material conveying system, a second material conveying system and a spray gun, wherein the structure of the first material conveying system is identical to that of the second material conveying system; a discharge port of a first material conveying pump of the first material conveying system is communicated with a mixing device through a first material conveying pipe; a first gear pump and a first flow meter are sequentially arranged on the first material conveying pipe; the output end of the mixing device is connected with the spray gun; the output end of a programmable logic controller (PLC) is respectively connected with the control ends of the first gear pump and a second gear pump; and the output ends of the first flow meter and a second flow meter are respectively connected with the input end of the PLC. In the invention, the PLC and the flow meters are used for accurately controlling the flow and the ratio of two-component coatings, and the flow and the ratio are automatically regulated by utilizing programs; and the ratio regulation range of two components is wider.

Hydraulic pump control system for construction machinery

Abstract: A hydraulic pump control system provided in a construction machine such as an excavator is provided. According to the hydraulic pump control system, a loss of a flow rate is reduced by initially supplying hydraulic fluid as much as necessary from a hydraulic pump to a hydraulic motor in order to accelerate a swing movement of an upper frame against a lower traveling structure or to make an upper swing structure swing.

Concrete pump hydraulic system for conveying high-viscosity concrete

Abstract: The utility model discloses a concrete pump hydraulic system for conveying high-viscosity concrete, which comprises a pumping system and a stirring system. The pumping system comprises a main oil pump, a first safety valve, a pressure relief valve, a first electro-hydraulic reversing valve, a second electro-hydraulic reversing valve, a main oil cylinder connected with the first electro-hydraulic reversing valve, a swinging oil cylinder connected with the second electro-hydraulic reversing valve, a first proximity switch arranged at the final position of the stroke of a main oil cylinder piston rod and a second proximity switch arranged at the final position of the stroke of a swinging oil cylinder piston rod. The stirring system comprises a gear pump, a second safety valve connected with the gear pump, a manual reversing valve and a stirring motor connected with the manual reversing valve. The main oil pump and the gear pump are driven by a power device. The hydraulic system can ensure the concrete pump to lead a distribution valve to act successfully when in high-strength concrete construction, realizes high-efficiency conveying of the high-strength concrete, and meets construction requirements.

Numerical Analysis of the Shaft Motion in the Journal Bearing of a Gear Pump

Abstract: This paper describes a numerical analysis of the dynamics of the shaft in the journal bearing of a gear pump. The modulus and direction of the load is a function of the relative position of the gears, causing a precession motion around an equilibrium position. The mean load is the function of the working pressure of the gear pump. The numerical analysis presented in this paper combines the equation of motion of the journal-gear set, based on the linearization of the fluid film load, with calculation of the load due to the pressure distribution on the gears. The damping and stiffness coefficients for the motion equation are calculated with the distributions around the shaft of the pressure and its derivatives. These distributions are calculated from the Reynolds equations using an in-house 2D finite element code with quadrangular elements; the equation of motion is solved with a fifth-order Runge-Kutta scheme. The results provide the stabilized position of the shaft for certain conditions, and allow limitation of the working pressure and the angular velocity of the pump in order to minimize, or to avoid, metal-metal contact and consequent wear of material. The results are compared with experiments and previously reported numerical results.

Rotor for pump, and internal gear pump using same

Abstract: An object is to meet the demands for increasing the number of teeth of a rotor in an internal gear pump while maintaining a theoretical discharge amount by using an equivalent body configuration so as to enhance the pump performance relating to discharge pulsation due to the increased number of teeth. In a pump rotor 1 formed by combining of an inner rotor (2) having N teeth and an outer rotor (3) having (N+1) teeth and disposing the rotors eccentrically relative to each other, the relational expression φD max < 1.7e·sin(π/180)/sin{π/(180·N)} is satisfied, φD max being a maximum value of a working pitch diameter of the inner rotor (2) and the outer rotor (3), and a working position (G) of the inner rotor (2) and the outer rotor (3) is always located rearward of an eccentric axis (CL) in a rotating direction of the rotor.

Two-component adhesive glue blending device

Abstract: The invention discloses a two-component adhesive glue blending device, comprising two pressure plates, lifting devices of the two pressure plates, two gear pumps and a flow control device, wherein the two gear pumps are respectively driven by a motor, the input end of the gear pump is connected with the glue outlet of the pressure plate and the output end is connected to a static mixer through pipelines; and the flow control device comprises two flow sensors which are respectively arranged on the pipeline and used for detecting the flow of each pipeline and outputting detection signals, the flow control device also comprises a controller which is used for receiving the detection signal of the flow sensor and controlling the motor speed according to detection signals. The glue blending device of the invention adopts secondary pressurization of the gear pump, thus being capable of generating greater delivery pressure, realizing glue blending operation on the adhesive with greater viscosity; and the gear pump can ensure stable delivery of the glue solution with no pressure fluctuation, the efficiency of blending glue is high, and the flow control device can ensure higher matching precision.

Modular internal gear pump or motor

Abstract: The invention discloses a modular internal gear pump or a modular motor, comprising a plurality of generalized components such as a shell, an internal gear pair, an input shaft, a fixed shaft tray component, a floating shaft tray component, a flange cover component, a rear cover component and the like, so as to form a barbell type combined structure connected in series, thus realizing modularization of functions, combination of structures and universalization of parts The invention has the advantages of good universalization of parts, flexible and simple assembly and excellent adaptability of structures, thus achieving the beneficial effects of reducing inventory of parts, shortening the cycle of production and goods delivery and reducing operation cost of products

Integrated internal gear pump with an electric motor

Abstract: The invention relates to a rotor pump having an internally toothed outer ring and an externally toothed inner ring which is mounted therein and intermeshes therewith, wherein the outer ring and the inner ring are arranged axis-parallel to one another, and the axes of the outer ring and of the inner ring are at a distance from one another, and the outer ring is connected to a hollow shaft motor with a stator which is fitted with windings, and to a rotor which is rotatably mounted therein, characterized in that the outer ring forms the rotor of the hollow shaft motor.

Gear pump and gear pump for brake apparatus

Abstract: A gear pump includes: a drive shaft; a first gear; a second gear; a first plate disposed between the first gear and the second gear, and arranged to liquid-tightly seal the first surfaces of the first and second gear; a pair of second plates disposed, respectively, on the second surfaces of the first and second gears, and arranged to liquid-tightly seal the second surfaces of the first and second gears, each of the second plates including a tooth top sealing portion having a seal surface arranged to seal a tooth top of the first gear and a tooth top of the second gear, and to form a suction portion with the first plate and the second plate; and an urging member arranged to urge the drive shaft toward the seal surface of the tooth top sealing portion of one of the first and second plates.