127 results about "Axial piston pump" patented technology

The invention discloses a digital hydraulic pump controlled by a high-speed switch valve bridge. The digital hydraulic pump comprises a motor, a swash plate type axial plunger pump, a variable adjusting unit, a pressure compensation unit, a closed-loop control unit, an unloading unit and a filter. The motor is connected with the swash plate type variable displacement piston pump; the variable adjusting unit is connected with the swash plate type variable plunger pump; the pressure compensation unit is connected with the variable adjusting unit to carry out differential pressure compensation on the variable adjusting unit; the closed-loop control unit is connected with the variable adjusting unit and controls the output flow of the variable adjusting unit according to a feedback signal; the high-speed switch valve is subjected to pressure difference compensation through the pressure difference compensator, so that the flow of the high-speed switch valve is not affected by load changes any more, and output pressure fluctuation of the swash plate type variable displacement piston pump is reduced; a high-speed switch valve bridge serves as a pilot level, and digital accurate control over the output pressure of the hydraulic pump is achieved through a closed-loop control unit; the high-speed switch valves are connected in parallel, multi-stage flow output and differential flow control are achieved, and the control precision and the response speed of the digital hydraulic pump are improved.

The invention discloses a variable displacement mechanism in an asymmetric pump, relates to the technical field of fluid transmission and control, and aims at solving the problems that an existing variable displacement mechanism is large in auxiliary oil source pressure, high in energy consumption and poor in control stability due to the fact that a swash plate is affected by one-way torque due to the oil port pressure difference of an axial plunger pump with three flow distribution windows. The variable displacement mechanism in the asymmetric pump comprises a variable displacement cylinder, wherein the variable displacement cylinder comprises a first cylinder barrel and a second cylinder barrel which are oppositely arranged in the movement direction of a piston; the piston is arranged in the first cylinder barrel and the second cylinder barrel; the first piston rod and the second piston rod are respectively arranged at two ends of the piston; the first piston rod is sleeved with the first stiffness spring, the second piston rod is sleeved with the second stiffness spring, and the stiffness of the first stiffness spring is larger than that of the second stiffness spring; and the at least two stop blocks are fixed on the inner wall of the first cylinder barrel. The pressure of the auxiliary oil source in the asymmetric pump is reduced, and the control stability is improved.

The invention relates to the technical field of hydraulic element testing, in particular to a high-pressure axial plunger pump bearing bush pair interface friction and oil film characteristic testing device. According to the device, 10-60 MPa adjustable oil pressure is provided through the hydraulic pipeline unit, the driving unit achieves power loading and friction monitoring through a servo motor and a torque sensor, the main body unit conveys high-pressure oil to a bearing bush contact face through an in-shaft cross-shaped oil duct structure to form a static pressure supporting oil film, and a micron-sized oil film sensor is integrated; the oil detection unit monitors oil parameters, and the signal acquisition and control unit performs closed-loop regulation on oil supply flow, motor rotating speed and swash plate load based on oil film thickness, torque and pressure signals. The method has the beneficial effects that 0.2 mu m-level oil film fracture identification is realized, the occurrence rate of dry friction is reduced by 82% through a cross-shaped oil duct in the shaft, and the oil film fluctuation rate lt is cooperatively controlled through multiple parameters; + / -3%, the safety interlocking mechanism responds abnormally within 0.3 s.

The invention relates to the technical field of hydraulic pressure, in particular to an axial plunger pump. According to the axial plunger pump, an oil discharge port and an oil suction port are formed in a plate body of a valve plate unit. And the oil discharge port and the oil suction port are arc-shaped and are concentrically arranged. And the inner diameter of the oil discharge port is equal to that of the oil suction port. And the outer diameter of the oil discharge port is equal to that of the oil suction port. The supporting layer is fixedly connected with the tray body. An oil discharge groove and an oil suction groove are formed in the supporting layer of the valve plate unit. The oil discharge groove is communicated with the oil discharge port. And the oil discharge groove is arc-shaped and is concentric with the oil discharge port. The inner diameter of the oil discharging groove is smaller than that of the oil discharging opening. And the outer diameter of the oil discharge groove is equal to that of the oil discharge port. The oil suction groove is communicated with the oil suction port. And the oil suction groove is arc-shaped and is concentric with the oil suction port. The outer diameter of the oil suction groove is larger than that of the oil suction opening. The inner diameter of the oil suction groove is equal to that of the oil suction opening. Therefore, the problem of how to improve the anti-overturning capability of the plunger pump cylinder body under the extreme working condition is solved.

The invention provides an axial plunger pump fault diagnosis method suitable for marking sample scarcity conditions, and belongs to the technical field of fault diagnosis, aiming at performance degradation caused by marking sample scarcity in axial plunger pump fault diagnosis of a deep learning model. According to the method, the dynamic pressure simulation model is constructed under the condition that the marked samples are scarce, and unmarked samples can be supplemented by generating high-quality simulation samples; a model migration framework and a semi-supervised multi-adversarial pre-adaptation strategy are constructed, and the generalization ability of the model in a target domain task is improved. Experimental results show that high-quality simulation samples are generated, and the plunger pump fault sample recognition rate under the condition that marked samples are scarce is increased.

The invention discloses a light-weight compact swash plate axial plunger pump, relates to the technical field of pumps, and aims to solve the problems that a traditional plunger pump is large in size, heavy, high in cost, difficult to maintain and the like, the light-weight compact swash plate axial plunger pump takes a pump shell as a main body, all parts are assembled in order, a main shaft drives, a swash plate is matched with a plunger to achieve liquid pressurization, and a mechanical water seal and a valve plate guarantee sealing and liquid conveying. When the pump is made of a duplex stainless steel material, the weight is 1.5 Kg, and the size of a main body is phi 76 * 109; the weight of the composite material is 1.0 Kg when the composite material is combined with duplex stainless steel, and the composite material is the smallest specification in the field of seawater desalination booster pumps. The device has the advantages of light weight and compactness, and adapts to portable equipment; the structure is simple, cost is low and reliability is high; the performance is equivalent to or even better than that of imported brands, the environmental adaptability is high, and the competitiveness in multiple fields is outstanding.

The present invention relates to a rotary tilting plate axial piston pump (1) for pumping liquids, comprising: a head (25); a plurality of cylinders (30) formed in the head (25) in a number greater than two, the plurality of cylinders (30) having axes (C) parallel to each other and arranged radially about a common axis (A) parallel to the axes of the cylinders; a plurality of pistons (75) each piston slidably inserted into a corresponding cylinder (30) of the plurality of cylinders (30) for pumping liquids; and a plurality of delivery pipes (145) formed in the head (25), each of the plurality of delivery pipes (145) extending directly from the corresponding cylinder (30) to a corresponding delivery valve (120) and arranged transversely to the axis (C) of the corresponding cylinder. The head (25) has a first side (61) and a second side (62), the second side (62) being opposite to the first side (61) with respect to an imaginary orthographic plane (S), the imaginary orthographic plane (S) including the common axis (A) and parallel to the axis (C) of the cylinder (30), wherein the plurality of cylinders (30) includes a first arranged cylinder and a second arranged cylinder, the axis (C) of the first arranged cylinder being between the first side (61) and the imaginary orthographic plane (S), and the axis (C) of the second arranged cylinder being between the second side (62) and the imaginary orthographic plane (S). A delivery conduit (145) extending from a cylinder (30) in the first arranged cylinder extends from the respective cylinder (30) toward the first side (61), and a delivery conduit extending from a cylinder in the second arranged cylinder extends from the respective cylinder (30) toward the second side (62).

This invention discloses an axial piston pump with a main shaft driven at a constant velocity to rotate an inclined cylinder assembly. The pump includes a pump body, a main shaft, a turntable on the main shaft, ball joints, and a cylinder mounted on the outer side of each ball joint. A piston mechanism is located between the cylinder and the turntable. A distribution plate is located on the outer side of the cylinder, and inlet / outlet flow channels are located inside the pump body. Multiple curved groove raceways or multiple straight groove raceways are located on the outer surface of the ball joints. Corresponding raceways are provided between the cylinder and the multiple curved groove raceways or multiple straight groove raceways. Torque is transmitted through the rolling contact of balls within the raceways, forming a fixed or telescopic ball cage type constant velocity universal joint transmission mechanism, achieving constant velocity drive of the inclined cylinder rotation by the main shaft. Because the components at both ends of the piston, namely the turntable and the cylinder, rotate at completely equal and synchronous speeds, the "floating" motion of the float in a float pump can be effectively solved, making the internal rotating components operate more stably under high-speed driving conditions and reducing friction and wear problems.

The invention discloses a stirring loss testing device for a rotating assembly in a high-speed plunger pump, and relates to the technical field of hydraulic elements, a simulation pump and a driving motor are installed on an inclinable platform through a connecting piece, a torque sensor is assembled on a cylinder body shaft of the simulation pump, and the simulation pump and the driving motor are in transmission connection through a coupler. The oil storage module and the stirring loss test module are isolated through the double-lip framework oil seal with the spring, and interference of a flow distribution pair is stripped; the inner wall of a plunger hole is pushed through a push rod in a cylinder hole of a cylinder body shaft, a traditional mode that a plunger is in direct contact with the cylinder hole is replaced, an oil way in the cylinder hole of the cylinder body shaft is adopted for oil injection lubrication, and measurement interference of a plunger pair is effectively removed; oil is injected to a spherical hinge joint by means of an oil path in the push rod, and the piston shoe pair is always soaked in the oil to realize sufficient lubrication by matching with the oil collection function of the inclinable platform and the swash plate with the oil storage tank, so that the measurement interference of the piston shoe pair is removed.

The invention relates to a hydraulic control circuit (11) for an orienting actuator (14) for orienting fan blades of a turbojet engine, the circuit (11) comprising an oil reservoir (17) and an axial piston pump (18) comprising a tiltable plate (23), as well as a control chamber (24) and a compensation chamber (27) for increasing the tilt of the plate (23) when the pressure inside these chambers increases, the pump (18) being supplied by the reservoir (17) and having its outlet configured so as to be able to be connected by a supply line (19) to one of the chambers (12, 13) of the orienting actuator (14), the other chamber of the orienting actuator (14) being connected to the reservoir (17), this control circuit comprising a valve (42) controlled by a computer (FADEC), which valve (42) allows the outlet of the pump (18) to be connected to the reservoir (17) in order to deactivate this pump (18).

The utility model discloses a novel swash plate type axial plunger pump which comprises a pump body, the pump body comprises a first pump body and a second pump body, the first pump body and the second pump body are connected through a connecting assembly, the first pump body and the second pump body comprise a shell and a transmission shaft, the transmission shaft is arranged in the shell, and the transmission shaft is arranged in the shell. The transmission shafts comprise the first transmission shaft and the second transmission shaft, the first transmission shaft and the second transmission shaft are each provided with a transmission assembly, and variable adjusting assemblies are arranged above the first pump body and the second pump body. The hydraulic system is simple in structure, reasonable in design and compact in overall structure arrangement, the use space of the hydraulic system is optimized, and simultaneous operation of the first pump body and the second pump body is achieved.

This invention discloses a dual-constraint incremental axial piston pump fault diagnosis method based on sample selection and playback, belonging to the field of fluid pressure and electrical digital data processing. The method includes: acquiring fault signals at the current moment and labeling them to obtain fault samples, constructing a fault diagnosis model; merging the fault samples at the current moment with old fault samples to form an incremental dataset, where the selection of old fault samples is based on improved sample profile coefficients and thresholds; inputting the incremental dataset into the fault diagnosis models at the current and previous moments respectively, further calculating the total incremental loss function composed of cross-entropy loss, cosine contrast loss, and surrogate loss, updating the model parameters through backpropagation until convergence, obtaining the fault diagnosis model trained at the current moment. This invention overcomes the catastrophic forgetting problem of learned fault knowledge in existing fault diagnosis models, and improves the continuous learning capability of the axial piston pump fault diagnosis model through incremental learning.

The invention provides a fixed clearance return stroke type high-speed axial plunger pump, and relates to the field of axial plunger pumps, the fixed clearance return stroke type high-speed axial plunger pump comprises a shell and a main shaft capable of rotating in the shell, the main shaft drives a cylinder body and an impeller to rotate, an axial channel is arranged in the cylinder body, a pre-tightening spring is arranged in the axial channel and provides pre-tightening force for a return stroke disc, and a plunger body can reciprocate in the axial direction. The end part of the plunger body is matched with the sliding shoe to slide on the swash plate, and a return stroke assembly is further arranged and comprises a return stroke plate, a fixed gap pressing plate and a fixing device; the return plate is limited between the fixed-gap pressing plate and the sliding shoe and arranged with the fixed-gap pressing plate in a spaced mode, and the fixing device is used for fixing the fixed-gap pressing plate to the swash plate. The return stroke assembly with the fixed gap is adopted, the problem that the sliding shoe excessively inclines and even disengages in the return stroke process is avoided, meanwhile, the return stroke disc utilizes the pre-tightening force of the center spring, and it is ensured that the sliding shoe is flexibly attached to and sealed with the swash plate under the low-speed working condition; the fixed gap pressing plate balances the centrifugal overturning moment of the sliding shoe through physical limiting under the high-speed working condition.

The application provides an axial plunger pump flow distribution disc and cylinder gap self-adapting adjusting device, which comprises a cylinder, a flow distribution disc, a gap detecting mechanism and an adjusting control mechanism; the gap detecting mechanism comprises a magnetic component, a magnetic field generator and a magnetic flux detecting sensor; the magnetic component is arranged on the cylinder, and the magnetic field generator and the magnetic flux detecting sensor are arranged on the flow distribution disc; the adjusting control mechanism is connected with the magnetic flux detecting sensor and the magnetic field generator respectively; the magnetic flux detecting sensor is used to detect the magnetic field strength change between the magnetic component; the adjusting control mechanism can obtain the gap between the cylinder and the flow distribution disc through the magnetic field strength change, control the magnetic field generator to generate different magnetic fields, and the magnetic field generator can interact with the magnetic component to adjust the gap between the cylinder and the flow distribution disc. The technical scheme can improve the wear and leakage problems, and improve the service life and performance of the pump.

The application provides an analysis method for an axial plunger pump with bearing faults under a liquid working condition, comprising the following steps: constructing a geometric structure model of an equation axial plunger pump rotor system to obtain a fluid acting force equation; decomposing a working medium mass into a rotor additional mass, a shell additional mass and a liquid coupling mass, and combining the fluid acting force equation with a friction force, a centrifugal force and a mass unbalance force equation of a cylinder body assembly to construct an axial plunger pump rotor dynamics equation; constructing a local defect fault dynamics model of a roller bearing to calculate an angular position of roller movement, and when the roller enters a defect, acquiring a time-varying displacement excitation and a time-varying contact stiffness excitation to be assembled into the dynamics equation to obtain a dynamics model with bearing faults; and analyzing the dynamics model with bearing faults to obtain critical rotating speeds of each fault element. By implementing the application, the analysis and calculation results are closer to actual values, and the vibration characteristic analysis and dynamic design work can be better carried out.

The invention provides an auxiliary dismounting device and method for a plunger pump. The auxiliary dismounting device comprises a walking mechanism used for movably supporting the whole device. A rotary V-shaped table and a movable lifting V-shaped table are arranged on a base bottom plate of the walking mechanism along the central axis; and a hoisting transfer frame is arranged above the walking mechanism. The dismounting device can be used for horizontally hoisting the axial plunger pump, so that a transmission shaft of the plunger pump is horizontally suspended, and the pump can be conveniently dismounted from an oil pump motor set; the rotary V-shaped table of the device can rotate by a certain angle, the movable lifting V-shaped table can vertically lift and move horizontally and longitudinally, and the two V-shaped tables are used in cooperation to stably bear different types of plunger pumps. The lifting transfer frame can achieve double-lifting-point horizontal lifting of the plunger pump, traditional tripod chain block single-lifting-point lifting is replaced, the lifting transfer frame is safer and more stable, and the lifting transfer frame can further transfer the detached plunger pump to the V-shaped table. The front side of the base bottom plate is designed to be a U-shaped notch which can be used for auxiliary disassembly of the plunger pump in a narrow space.

The invention discloses a double-rotation-direction axial plunger pump and a valve structure. The problem that in the prior art, a symmetrical valve plate of a double-rotation-direction axial plunger pump cannot achieve pre-boosting is solved. The double-rotation-direction axial plunger pump comprises a shell, a cylinder body, a valve plate, a swash plate and a plurality of plungers, the valve plate is arranged in the shell and located at one end of the cylinder body, a first oil suction port and a second oil suction port are further formed in the valve plate, a first included angle is formed between the first oil suction port and the center line of the valve plate, and a second included angle is formed between the second oil suction port and the center line of the swash plate. A first included angle is formed between the first oil suction port and the center line of the valve plate, a second included angle is formed between the second oil suction port and the center line of the valve plate, and the first included angle is equal to the second included angle, so that when the double-rotation-direction axial plunger pump rotates, one of the first oil suction port and the second oil suction port can be opened for auxiliary oil suction; and the other closed side can be used for pre-boosting the plunger cavity, so that pre-boosting on the valve plate of the double-rotation-direction axial plunger pump becomes possible.

The invention relates to an axial piston machine (1), in particular an axial piston pump, with a piston drum (2) that can be driven in at least one direction of rotation (22), with cylinders (10) arranged in the piston drum which are spaced apart from each other in the direction of rotation by a piston pitch (24) and are designed to slidably receive pistons (4) having a piston diameter (34), wherein longitudinal axes (16) of the pistons are arranged parallel to each other on a pitch circle (28) having a pitch circle diameter (26), and wherein: 0.377 z K ≤ (DT, K d K) ≤ 0.4948 z K, where D T,K the pitch circle diameter, d K the piston diameter and z K The number of pistons corresponds to this. Such an axial piston pump is quiet in operation yet compact.

This invention relates to a method and computer program for setting and / or starting the drive system of a molding apparatus, particularly an extruder, to a preset operating speed. Furthermore, this invention relates to a corresponding molding apparatus. The drive system (100) comprises a hydraulic piston cylinder unit (130), which includes a punch (132) for extruding material in the molding apparatus through a die (220). The piston cylinder unit (130) is connected to a pump assembly (110) via a hydraulic network (120). The pump assembly (110) includes at least one axial piston pump and an electric motor (M1) assigned to it for delivering hydraulic fluid to the piston cylinder unit via the hydraulic network. In order to save energy during the extrusion time of the forming equipment while the axial piston pump and the electric motor driving it are running, the method according to the invention specifies that the swing angle (α1) of the first axial piston pump (P1) and the rotational speed (n1) of the first electric motor (M1) and (if necessary) the swing angle (α2...) of the additional axial piston pumps are set or changed, so as to achieve the preset target operating speed (Vsoll) with the lowest possible overall efficiency.

The utility model relates to the technical field of axial plunger pumps, in particular to a duplex axial plunger pump cylinder body capable of resisting cylinder body overturning, a plurality of spring connecting holes are formed in the periphery of a central shaft cavity at the outer end of the cylinder body in the circumferential direction, and a plurality of cylinder holes are formed in the position, close to the outer edge, of the outer end of the cylinder body in the circumferential direction. A flow distribution surface of a spherical concave surface structure is arranged in the middle of the inner end face of the cylinder body, a plurality of inwards-inclined holes are formed in the position, located on the periphery of the center shaft cavity, of the flow distribution surface in the circumferential direction, the inwards-inclined holes are communicated with the cylinder holes in a one-to-one correspondence mode and used for communicating the flow distribution windows with the cylinder holes, and the cylinder holes are plunger cavities. The inward inclined design of the orifice can effectively reduce the gaseous cavitation of the plunger cavity by utilizing the centrifugal effect of the rotating fluid. And a plurality of groups of micro pits are sequentially formed in the flow distribution surface from inside to outside, the forming efficiency and the bearing capacity of an oil film between the cylinder body and the flow distribution plate are effectively improved through the structure, the hydraulic overturning moment is balanced, and therefore the overturning degree of the cylinder body is relieved.

The invention discloses a digital axial plunger pump / motor, and belongs to the field of hydraulic elements. The device comprises a fixed cylinder body, a transmission shaft, an inner ring swash plate, an outer ring swash plate and a plunger assembly, the cylinder body is provided with double rows of plunger cavities, and the transmission shaft is supported in the center of the cylinder body through a bearing. The inner ring swash plate and the outer ring swash plate are rigidly connected with the shaft, working face contours of the swash plates are symmetrical curved surfaces and provided with guide grooves, the plungers are arranged in plunger cavities, reset springs are arranged at the front ends of the plungers, guide balls are arranged at the tail ends of the plungers, and the guide balls are in rolling contact with the swash plate guide grooves. When the pump is used, the transmission shaft drives the swash plate to rotate, the plunger moves linearly in a reciprocating mode through the curved surface profile, and the single plunger completes two times of oil discharge and two times of oil suction every time the swash plate rotates by a circle. When used as a motor, the digital valve system controls high-pressure oil to enter the plunger cavities to push the plungers, the balls roll along the curved surface of the swash plate to convert linear motion into continuous rotation of the swash plate and the transmission shaft, the single plunger completes two times of oil inlet and two times of oil return every time the single plunger rotates, and efficient conversion is achieved.

The invention relates to a hydraulic control circuit (11) for a fan blade pitch control actuator (14) of a turbojet engine, comprising an oil reservoir (17), an axial piston pump (18) having a tilting swashplate (23) and a control chamber (24) and a compensation chamber (27) to increase the tilt of the swashplate (23) when the pressurization of these chambers increases, the pump (18) being supplied by the reservoir (17) and having its outlet configured to be connected by a supply line (19) to one of the chambers (12, 13) of the pitch control actuator (14), the other chamber of the pitch control actuator (14) being connected to the reservoir (17), this control circuit comprising a valve (42) controlled by a computer (FADEC) allowing the outlet of the pump (18) to be connected to the reservoir (17) in order to deactivate this pump (18). Figure for the abbreviation: Figure 2

The invention relates to a hydrostatic axial piston machine (1), in particular an axial piston pump, with an adjustable displacement volume, which is operated in a closed circuit, wherein the displacement volume is adjustable by means of an actuating device (4), wherein the actuating device (4) comprises a pressure-cutting function (16) which has a pressure-cutting valve (15) which is actuated depending on the pressure at a first pressure port (A) of the axial piston machine (1) and depending on the pressure at a second pressure port (B) of the axial piston machine (1). The pressure-cutting valve (15) is operatively connected to a first actuating piston (35a), which is actuated by the pressure at the first pressure port (A), and to a second actuating piston (35b), which is actuated by the pressure at the second pressure port (B).

The utility model relates to swash plate type axial plunger pump technical field, especially a kind of high-speed axial plunger pump, including shell, transmission shaft, variable mechanism and rotary assembly, rotary assembly includes the cylinder body, plunger, sliding shoe, swash plate support, ball hinge, return disc, return spring and flow distribution disc of assembly. Among them, transmission shaft and cylinder body adopt drum spline connection of circular arc type, avoid the problem that cylinder body overturns and is stuck;Sliding shoe and plunger adopt ball head articulation, plunger can wrap around the ball head rotation of sliding shoe, thereby reduce the distance of sliding shoe centroid to ball hinge center, reduce the centrifugal overturning moment of sliding shoe, improve the anti-overturning capacity of sliding shoe;Plunger is coaxially provided with cylindrical annular cavity, can reduce mass, reduce the influence of centrifugal force to sliding shoe and cylinder body;And the bottom surface of sliding shoe is plated with wear-resistant layer, can reduce the wear degree of sliding shoe bottom surface. Overall improve service life, avoid the overturning failure problem of sliding shoe and cylinder body in high-speed operation process.

The present invention discloses an energy recovery device and method for the flow distribution and pressure relief phase of a swash plate axial piston pump. Unlike conventional flow distribution plates, which connect a recovery hole with the interior of the pump housing, allowing the plunger to discharge high-pressure oil into the housing cavity during pressure relief, the present method connects the recovery hole with a recovery chamber, allowing the high-pressure oil discharged during the plunger unloading process to be recovered in the chamber. Whenever the plunger enters the oil intake phase, the high-pressure oil stored in the chamber is returned to the plunger cavity through the recovery hole for pressure compensation, thereby achieving energy recovery and reuse during the flow distribution process.

The utility model relates to the technical field of axial plunger pumps, and particularly discloses a novel axial plunger pump vibration and noise reduction valve plate capable of preventing a cylinder body from overturning. An oil absorption waist-shaped groove and an oil discharge waist-shaped groove are formed in a valve plate circular ring on the front wall of a valve plate body and located on the left side and the right side of a shaft hole respectively; an upper dead point and a lower dead point are arranged at the positions, located at the top end and the bottom end of the flow distribution circular ring, of the front wall of the flow distribution plate body, oil suction damping grooves and first damping holes are formed between the bottom ends of the oil suction kidney-shaped grooves and the lower dead points, and the oil suction damping grooves communicate with the front portions of the bottom ends of the oil suction kidney-shaped grooves. A second damping hole, a third damping hole and a fourth damping hole are sequentially formed between the top end of the oil discharge kidney-shaped groove and the top dead center from left to right, and an oil discharge damping groove communicated with the oil discharge kidney-shaped groove is formed in the position, corresponding to the second damping hole, of the front wall of the valve plate body. The rear wall of the valve plate body is provided with an arc-shaped connecting groove for communicating the rear ends of the second damping hole, the third damping hole and the fourth damping hole with the kidney-shaped oil discharging groove, and an oil discharging groove is formed in the position, corresponding to the first damping hole, of the rear wall of the valve plate body in the radial direction; and pressure and flow pulsation generated in the flow distribution process are reduced, so that vibration and noise are reduced.

The utility model discloses a height and angle adjustable test fixture for a plunger pump, and belongs to the technical field of plunger pumps, the plunger pump test fixture comprises a fixed frame, an adjusting plate, a rotating plate and a clamping jaw mechanism, the adjusting plate comprises a first plate body and an adjusting part, and the first plate body is provided with a first avoiding hole; the rotating plate comprises a second plate body, a rotating shaft and an adjusting disc, the rotating shaft is connected with the second plate body, a second avoiding hole is formed in the second plate body, the rotating shaft is rotatably installed on the first plate body, and the second plate body is provided with a straight shaft position and a plurality of inclined shaft positions; a containing groove is formed in the adjusting part, the end, close to the containing groove, of the rotating shaft is connected with an adjusting disc, multiple positioning grooves are formed in the side wall of the containing groove, and a clamping part is arranged on the periphery of the adjusting disc; the clamping jaw mechanism comprises a plurality of clamping jaw assemblies. The plunger pump test fixture can respectively clamp the swash plate type axial plunger pump and the inclined shaft type axial plunger pump when the second plate body is in the straight shaft position and the inclined shaft position, so that the universality of the plunger pump test fixture is effectively improved.

A balanced axial piston pump for a hydraulic tool is specified. The balanced axial piston pump comprises a camshaft, cam followers, a stroke block, a spring, a pump piston, a piston chamber, and a distributor. The rotation of the camshaft simultaneously drives the radial movement of the cam followers. The radial movement of the cam followers causes a linear movement of the stroke block along the axis of the hydraulic tool. The spring presses the piston against the stroke block, keeping the piston in contact with it. The linear movement of the stroke block moves the piston linearly within the piston chamber, thereby pumping oil and providing hydraulic power.

The present disclosure relates to the technical field of plunger pump, and provides an axial plunger pump with good self-priming performance, which comprises a pump shell assembly, a base, a distribution disc, a swash plate and a cylinder body, the base is provided with a medium input channel and a medium output channel, the distribution disc is provided with a first through groove and a second through groove, the cylinder body is provided with a plurality of plunger holes, a sliding plunger is slidingly arranged in the plunger hole, and the sliding plunger is used for pumping medium from the medium input channel to the medium output channel after sliding; the wear-resistant ring is provided with a plurality of sliding parts and friction parts, the sliding parts are slidingly arranged in the plunger holes one by one, the sliding direction of the sliding part is parallel to the sliding direction of the sliding plunger, after the sliding part slides, the friction part is driven by the sliding part to abut against the top of the distribution disc away from one end of the sliding part, the sliding part is provided with a third through hole in communication with the plunger hole, and the friction part is provided with a plurality of distribution windows in one-to-one communication with the third through hole. Through the above technical scheme, the technical problem that the distribution disc needs to be frequently overhauled and replaced in the prior art is solved.

The swash plate type axial plunger pump shell structure comprises a pump body and a shell, a flow channel is formed between the pump body and the shell, a front end cover and a rear end cover are arranged at the two ends of the shell, four sets of first through holes are formed in the front end cover in the circumferential direction, a first cover plate is installed on the outer surface of the front end cover, and four sets of second through holes are formed in the rear end cover in the circumferential direction; a second cover plate is installed on the outer surface of the rear end cover, and Venturi modules are installed at the positions, located on the front end cover and the rear end cover, in the flow channel. The first cover plate and the second cover plate which are synchronously opened and closed are arranged at the two ends of the shell, the Venturi module in the flow channel is combined, pulse type forced convection heat dissipation is achieved, when the first cover plate and the second cover plate are opened, external cold air is accelerated through the Venturi module to form high-speed low-pressure airflow, convection heat exchange on the surface of the pump body is strengthened, and the heat dissipation efficiency is improved. And when the first cover plate and the second cover plate are closed, air in the flow channel is heated and pressurized, energy is stored for next airflow injection, and an efficient heat circulation export mechanism is formed.