98 results about "Variable displacement pump" patented technology

The invention relates to the technical field of injection molding machine hydraulic control, in particular to an injection molding machine hydraulic pump control system and a control method thereof, and aims to solve the problems of high energy consumption, high cost or poor temperature control of a traditional hydraulic scheme. The system comprises a hydraulic oil tank, a driving unit and an oil way control module. The driving unit comprises a driving motor, and a fixed displacement pump and a plurality of swash plate type variable displacement piston pumps which are driven by the driving motor, and swash plates of the variable displacement pumps can be switched between negative and positive angles so as to adjust the displacement or actively suck oil; the oil way control module is provided with a flow collecting valve set capable of switching flow collecting / independent states of oil outlet ways of the constant displacement pump and the variable displacement pump, the integrated cooling unit forms an independent cooling filtering loop, the temperature and pressure adjusting assembly is combined with a temperature sensor to control temperature and adjust pressure, and the pressure limiting protection valve set is connected with the constant displacement pump and the variable displacement pump. And the pressure limiting protection valve is matched with a pressure sensor to realize overpressure protection. According to the invention, cost and energy saving are both considered, precise temperature control and pressure protection are realized, and system stability and plastic part forming precision are improved.

The invention relates to the technical field of non-variable-capacity pump set parallel control, and discloses a multi-blower parallel air volume control method, which comprises the following steps of: acquiring the real-time rotating speed and the real-time input power of a driving frequency converter of each single blower in a parallel system, and superposing a periodic rotating speed perturbation signal at a common pressure given value to obtain a multi-blower parallel air volume control result; power response amplitudes of all single blowers are extracted synchronously, the change rate of real-time power relative to the rotating speed is calculated to generate a power response gradient representing the energy conversion characteristic of the unit, the unbalanced blowers are recognized according to deviation parameters of the power response gradient relative to the global average value, the rotating speed instruction gain of the blowers is reduced, and the unit energy conversion characteristic is obtained. According to the method, load distribution is converted into an active adjustment mechanism based on the physical characteristics of the impeller, accurate identification of the offset of the physical operation sites of the parallel unit is achieved, and the accuracy of the offset of the physical operation sites of the parallel unit is improved on the premise that branch flow sensing hardware is not needed. And the recessive surge risk caused by single-machine performance discretization is inhibited.

A system includes a variable displacement pump (VDP) in fluid communication with an inlet line and with an outlet line. The VDP includes a variable displacement mechanism configured to vary pressure to the outlet line. A bypass valve (BPV) includes a BPV inlet in fluid communication with the outlet line, and a BPV outlet in fluid communication with a bypass line that feeds into the inlet line upstream of the VDP. A minimum pressure shutoff valve (MPSOV) is connected in fluid communication with the outlet line, configured to block flow through the outlet line for shutoff. The MPSOV is connected in fluid communication with the BPV for triggering recirculation through the BPV.

The application relates to the technical field of centrifugal pumps, and particularly discloses a high-sealing non-variable-volume pump and components thereof, which comprises a pump shell and an impeller, a water inlet and a water outlet are respectively arranged on the pump shell, the pump shell is in a volute type, the volute type comprises a wide section and a narrow section, and the pump shell further comprises a flow assisting mechanism which comprises a flow distribution port and a flow distribution sleeve arranged on the narrow section of the pump shell, a plurality of liquid inlet holes are arranged in a circular array on the water inlet, and the flow distribution sleeve is covered on the flow distribution port and the liquid inlet hole at two ends respectively. In the application, the flow distribution sleeve guides the fluid into the flow distribution sleeve along the flow distribution port at the narrow section of the volute type with the largest pressure during the operation of the impeller, then the flow distribution sleeve supplements the fluid to the water inlet of the pump shell, and the negative pressure at the water inlet is supplemented to reduce the cavitation and prolong the service life of the centrifugal pump.

The utility model discloses a novel hydraulic control system of household garbage dry-wet classification equipment, and belongs to the field of hydraulic control. The hydraulic control system comprises a large variable pump connected and driven by a first motor, a small variable pump connected and driven by a second motor, a duplex vane pump connected and driven by a third motor, a cooling circulating pump connected and driven by a fourth motor, a pressure control valve group, an extrusion roller feeding control valve group, a cooperative control valve group, an extrusion oil cylinder and a low-speed large-torque hydraulic motor; the device comprises a feeding oil cylinder, a door blocking oil cylinder, a door lifting oil cylinder, a push-pull box oil cylinder, a box locking oil cylinder, an oil return filter, a circulating filter, an air cooler and an oil tank. According to the utility model, the multifunctional control variable pump with constant power and remote constant-pressure control is adopted, so that the device is suitable for the extrusion working condition of household garbage dry-wet classification equipment, the working efficiency is higher, and small-load high speed and large-load low speed are easier to realize; and the system is more energy-saving and smaller in heat generation.

The application discloses a kind of pneumatic-hydraulic hybrid wave energy device energy conversion systems, including nozzle, impulse turbine, torque output shaft, shaft coupling, rotational speed sensor, variable displacement pump, energy accumulator, manual reversing valve, first electromagnetic ball valve, second electromagnetic ball valve, hydraulic motor, permanent magnet generator, PID control module, hydraulic oil tank, oil pressure sensor, first hysteresis comparator, second hysteresis comparator, air pressure sensor and overflow valve.The application realizes an innovative pneumatic-hydraulic energy conversion mode by combining air turbine and hydraulic conversion system.

A dispensing pump includes a linear actuator mounted on a base. The linear actuator includes a drive rod having a coupler. The coupler joins the drive rod to a first end of a connecting member. A second end of the connecting member is secured to a lower base portion of the base. An attachment plate attaches a motor to a first end of an upper base portion of the base. A flag is secured to the drive rod coupler, wherein the flag moves directly with the drive rod. The flag includes a body and a calibration element. The calibration element is positionally adjustable relative to the flag body. The calibration element is adapted to activate a proximity sensor when the linear drive is in a home position. The home position is adjustable upon adjustment of the calibration member.

A hydraulic pump circuit for a hydraulic system on a work machine may include a variable displacement pump in fluid communication with a hydraulic system via a supply line on a work machine. The variable displacement pump may be configured to provide hydraulic fluid flow to the hydraulic system. The hydraulic pump circuit may also include a stroke actuator in fluid communication with the supply line via a restriction orifice and may be configured for controlling the displacement volume of the variable displacement pump. The hydraulic pump circuit may also include a control valve configured for controlling the stroke actuator to upstroke and de-stroke the pump. The hydraulic pump circuit may also include a cutoff valve arranged and configured to de-stroke the pump when a threshold pressure develops within the hydraulic system.

A hydraulic system (1) according to one embodiment comprises: a first bidirectional pump (2) connected to a head-side chamber (4h) of a differential cylinder (4) via a head-side line (21) and to a rod-side chamber (4r) of the differential cylinder (4) via a rod-side line (22), wherein the first bidirectional pump (2) is a variable displacement pump; and a second bidirectional pump (3) connected to the head-side line (21) via a supply / discharge line (31), wherein the second bidirectional pump (3) is a variable displacement pump. The hydraulic system (1) further comprises: a low-pressure selector valve (6) connected to the head-side line (21) via a first outlet line (61) and to the rod-side line (22) via a second outlet line (62); and a position detector (9) that detects a position of the low pressure selector valve (6).

This utility model relates to the field of hydraulic pumping unit technology, and in particular to a one-to-two hydraulic pumping unit, comprising a mounting base plate, with support frames mounted on both the left and right sides of the top front side of the mounting base plate. Servo hydraulic cylinders are installed inside the support frames, and displacement sensors are installed inside the servo hydraulic cylinders. A hydraulic oil tank is bolted to the rear side of the top of the mounting base plate, and a proportional valve and a variable displacement pump motor are bolted to the top of the hydraulic oil tank. An accumulator is connected to the front side of the solenoid valve assembly. The proportional valve controls the two variable displacement pump motors to alternately work to supply oil to the servo hydraulic cylinders at both ends. When one servo hydraulic cylinder rises, the other servo hydraulic cylinder descends, transferring hydraulic energy to the other lifting variable displacement pump motor, causing the servo hydraulic cylinders at both ends to reciprocate. This one-to-two configuration achieves energy recovery and improves production efficiency.

The utility model relates to the technical field of hydraulic pressure, in particular to an open type plunger variable pump which comprises a pump body, a control valve body is installed on the pump body, the control valve body comprises a flow control valve and a pressure valve, a flow valve cavity is formed in the flow control valve, and a pressure valve cavity is formed in the pressure valve. A middle oil channel connecting the flow valve cavity and the pressure valve cavity is arranged in the control valve body, a pressure oil channel connecting the pressure valve cavity and the variable cavity is arranged in the control valve body, a flow oil channel connecting the flow valve cavity and the pressure valve cavity is arranged in the control valve body, an oil return channel is arranged on the pump body, one end of the oil return channel is connected with the flow oil channel, and the other end of the oil return channel is connected with the variable cavity. The other end of the oil return channel is connected with the oil outlet, the control valve body is provided with a load oil port connected with a load pipeline, and the load oil port is communicated with the flow valve cavity. According to the open type plunger variable pump, the flow and the pressure of the variable pump can be accurately and visually controlled, and the response speed, the equipment stability and the operation convenience of a system are improved.

A hydraulic pump circuit for a hydraulic system on a work machine may include a variable displacement pump in fluid communication with a hydraulic system via a supply line on a work machine. The variable displacement pump may be configured to provide hydraulic fluid flow to the hydraulic system. The hydraulic pump circuit may also include a stroke actuator in fluid communication with the supply line via a restriction orifice and may be configured for controlling the displacement volume of the variable displacement pump. The hydraulic pump circuit may also include a control valve configured for controlling the stroke actuator to upstroke and de-stroke the pump. The hydraulic pump circuit may also include a cutoff valve arranged and configured to de-stroke the pump when a threshold pressure develops within the hydraulic system.

A hydraulic system includes: a first bi-directional pump connected to a head-side chamber of a single-rod cylinder by a head-side line and connected to a rod-side chamber of the single-rod cylinder by a rod-side line; and a second bi-directional pump connected to the head-side line by a supply / discharge line, the second bi-directional pump being a variable displacement pump. The hydraulic system further includes a low-pressure selection valve connected to the head-side line by a first discharge line and connected to the rod-side line by a second discharge line, wherein the low-pressure selection valve allows the second discharge line or the first discharge line to communicate with a relief line on which a relief valve is located.

This invention discloses a method for designing the additional angle of the swashplate in a constant pressure variable displacement piston pump, comprising the following steps: A. When the additional angle β is 0, based on the inlet pressure P of the variable displacement pump... 始 Constant pressure P 终 Given the maximum swashplate angle α, determine the compression angle B. Based on equations 1 and 2), calculate the corresponding additional angle β at the maximum swashplate angle α. Then, using equation 3), calculate the angle C between the z-axis and the low-pressure zone oil window of the distributor plate. Calculate the curves showing the volume ratio changing with the additional angle β at different swashplate angles α. The intersection of these curves represents the optimal design value for the additional angle β under different operating conditions. This invention enables the variable pump to minimize pressure pulsation under any operating condition, thereby improving the performance of the constant pressure variable piston pump and the reliability and lifespan of the onboard hydraulic system.

The utility model discloses a mining machine cutting cylinder hydraulic control system which comprises a variable oil pump, the variable oil pump is connected with a first pipeline and a second pipeline, a left side motor and a three-way selector valve are arranged between the first pipeline and the second pipeline, the tail end of the first pipeline is connected with a first control valve, and the tail end of the second pipeline is connected with a second control valve. A reversing valve is arranged at the other end of the three-way selection valve and connected with a sequence control valve, the direction of the reversing valve is selected through the sequence control valve, one port of the reversing valve is connected with the control ends of the first control valve and the second control valve, the other port of the reversing valve is connected with a third control valve, and closed pipelines are arranged at one ends of the first control valve and the second control valve. The third control valve is connected to a closed pipeline in parallel, and a right motor is arranged on the closed pipeline. By switching the independent work of the left motor and the simultaneous work of the left motor and the right motor, the stepless speed regulation of the cutting cylinder is realized, so that the speed regulation interval is expanded, and the requirements under different working conditions are met.

The invention discloses a distributed hydraulic driving system for a guniting robot, and belongs to the technical field of engineering machinery, and the distributed hydraulic driving system comprises an engine for providing power; the input end of the transfer case is connected with an output shaft of the engine; the input ends of the four variable pumps are respectively connected with the four output ends of the transfer case; each variable displacement motor and a variable displacement pump form an independent hydrostatic transmission loop through a hydraulic oil way, an output shaft of each variable displacement motor is connected with a hub reduction gear, and the output ends of the hub reduction gears drive four crawler walking devices of the guniting robot respectively. The maneuverability and reliability of the robot in narrow and fluctuating roadways can be enhanced, and the adaptability to complex terrains and the operation continuity are remarkably improved.

This utility model provides a hydraulic system and a dump truck. The hydraulic system includes a hydraulic oil tank, a variable displacement pump, a steering valve assembly, a steering mechanism, a brake valve assembly, a parking brake, a lifting mechanism, an emergency pump, and an emergency valve assembly. The variable displacement pump and the emergency pump are connected to the hydraulic oil tank. The steering valve assembly is connected to the variable displacement pump and supplies oil to the steering mechanism. The lifting mechanism is connected to the steering valve assembly via a first oil circuit. The brake valve assembly is connected to the parking brake via a second oil circuit. The emergency valve assembly is connected to the emergency pump, and is connected to the steering valve assembly via a first emergency line and to the brake valve assembly via a second emergency line. The oil passing through the emergency pump is defined as emergency oil. The emergency oil, via the emergency valve assembly, can be used for emergency steering, emergency lifting, and releasing the parking brake. This utility model's hydraulic system can solve the problem of dump trucks being unable to work normally under fault conditions and the need for relocation and repair, improving relocation and repair capabilities.

The invention relates to the technical field of driving gear shifting control of hydrostatic driving vehicles, in particular to an electro-hydraulic system of a hydrostatic driving vehicle, a control method and engineering machinery. Comprising a variable displacement motor, a forward rotation oil port and a reverse rotation oil port are connected with a variable displacement pump through a forward rotation oil way and a reverse rotation oil way respectively, and the variable displacement motor is further connected with a displacement control mechanism. The bypass valve group is connected between the forward rotation oil way and the reverse rotation oil way and comprises a bypass control mechanism used for controlling connection and disconnection between the forward rotation oil way and the reverse rotation oil way. The input end of the gearbox is connected with an output shaft of the variable displacement motor, the output end of the gearbox is connected with the wheel transmission mechanism, and the synchronizer is connected with the gear switching control mechanism. Zero displacement control of the motor can be achieved through the displacement control mechanism, on the basis of achieving zero displacement control of the motor, the bypass control mechanism can prevent a gearbox from being damaged by heavy load sliding abrasion when the gear switching control mechanism executes gear shifting through unloading, and safety control over the gear shifting process is achieved.

The invention discloses an agricultural machinery chassis closed type hydraulic walking system and agricultural machinery equipment, and relates to the technical field of agricultural equipment control, the agricultural machinery chassis closed type hydraulic walking system comprises an engine, the engine is connected with a first output shaft and a second output shaft through a one-to-two dragging box, and the first output shaft is connected with a driving module of two right wheels; a second output shaft is connected with a driving module of the two left wheels; the driving module comprises a variable pump and a double-speed hydraulic motor, and two working oil ports of the variable pump are correspondingly connected with two oil ports of the double-speed hydraulic motor to form a closed circulation loop; the double-speed hydraulic motor is connected with a motor control loop and a heat dissipation branch; the motor control loop comprises an electromagnetic reversing valve, the heat dissipation branch comprises an overflow valve, a spring reset reversing valve and a radiator, the electromagnetic reversing valve and the spring reset reversing valve are both connected with two oil ports of the double-speed hydraulic motor in parallel, and the radiator is connected with the spring reset reversing valve through the overflow valve. Through four-pump four-motor closed driving and electromagnetic proportional control, the movement reliability of the chassis is ensured.

The invention discloses a rock drill drilling hydraulic system, which relates to the technical field of rock drill hydraulic systems and comprises a hydraulic power unit, an impact execution unit, a propulsion execution unit, a geological sensing unit, an intelligent control unit and an oil temperature adjusting unit. A variable displacement piston pump of the hydraulic power unit supplies energy to the system; the geological sensing unit collects geological parameters through a drill rod torque sensor and a vibration sensor; the intelligent control unit calls a pre-stored mapping relation table to be matched with target impact pressure, precise pressure control is achieved through a PID adjusting impact valve set, and the displacement of a variable pump is synchronously adjusted; the oil temperature adjusting unit is linked with the plate heat exchanger through the temperature sensor to cool oil temperature. According to the system, self-adaptive adjustment of impact pressure of different geological stratums is achieved, throttling loss is avoided, oil temperature rising is relieved, the drilling efficiency is improved by 15%-20% through cooperation of the two, the continuous operation oil temperature is controlled to be 60 DEG C or below, the service life of equipment is prolonged, and the maintenance cost is reduced.

The invention relates to the technical field of liquid pumps, in particular to a liquid variable displacement pump which comprises a pump shell, a driving gear and a driven gear are arranged in the pump shell, the driven gear can move front and back relative to the driving gear, and a first sealing assembly and a second sealing assembly are arranged in the pump shell at intervals. A liquid conveying cavity is formed between the first sealing assembly and the second sealing assembly, the first sealing assembly synchronously moves front and back along with the driven gear, the front-back position of the second sealing assembly in the pump shell is fixed, the first sealing assembly is in sealing contact fit with one end of the driven gear, and the second sealing assembly is in sealing contact fit with one end of the driving gear. A first sealing block is arranged on the periphery of the driving gear in a floating mode, a second sealing block is arranged on the periphery of the driven gear in a floating mode, the first sealing block exerts radial jacking pressure on the driving gear, and the second sealing block exerts radial jacking pressure on the driven gear. The technical problem that the working stability of the gear pump is affected due to flow pulsation and pressure pulsation generated by an existing variable-capacity gear pump is solved.

A fluid system includes a boost pump and a variable displacement pump along a main leg configured to output fluid within a pressure range and at variable flow rates. An auxiliary leg of the fluid system includes an auxiliary pump configured to receive a portion of the fluid from the main leg and to output pressurized fluid to a control valve of the variable displacement pump and multiple actuator modules. Each actuator module includes an electromechanical actuator and a collocated control unit.

Variable displacement pumps and related methods are disclosed herein. Disclosed herein are example pump housings defining a fluid path between an inlet and an outlet, the pump housing including an interior surface; a shaft; and a vane disposed adjacent to the interior surface, the vane coupled to the shaft, the vane including a metal core; and a ceramic interface coupled to at least one of a surface of the metal core, a tip of the vane, or an interior surface.

The invention relates to a hydraulic system, in particular an electric motor pump, for supplying a consumer, in particular an aircraft hydraulic system, comprising an electric motor with variable motor speed, a variable displacement pump driven by the electric motor, a high-pressure outlet and a low-pressure inlet for connecting to a consumer of the hydraulic system, a bypass in whose bypass line a throttle is provided for heating the fluid flowing through the throttle, a switching device designed to selectively connect the high-pressure outlet to a high-pressure side of the variable displacement pump and the low-pressure inlet to a low-pressure side of the variable displacement pump or the high-pressure side of the variable displacement pump to the low-pressure side of the variable displacement pump via the bypass, and an evaluation and control unit designed toto determine the volumetric pump efficiency of the hydraulic system by determining the actual flow rate of the variable displacement pump using the bypass.

A drive system for a work vehicle, for example a truck-mounted forklift, with at least one driven wheel, and the drive system includes a hydraulic pump designed to drive the driven wheel, and an electric motor mechanically coupled to the hydraulic pump. The electric motor is designed to drive the hydraulic pump, and the hydraulic pump is a variable displacement pump.

A refuse vehicle includes a chassis and a vehicle body. A variable displacement pump is positioned within the vehicle body and is configured to pump hydraulic fluid from a hydraulic fluid reservoir into a high pressure line of a hydraulic circuit. A lifting system on the vehicle includes at least one actuator in fluid communication with the variable displacement pump, which delivers pressurized hydraulic fluid from the hydraulic fluid reservoir to the actuator through the high pressure line to adjust a position of the actuator. A valve is positioned downstream of the variable displacement pump. In a first valve position, the valve restricts flow outward from the high pressure line. In a second valve position, the valve directs fluid from the high pressure line into a lower pressure line to reduce a hydraulic pressure within the high pressure line and adjust an output parameter of the variable displacement pump.

This invention relates to the field of variable displacement pump technology and discloses a crankshaft pump assembly, including a housing. Within the housing are a plunger pump assembly and a crankshaft drive assembly. The plunger pump assembly includes a pump cylinder and a plunger. A transfer chamber is located at the bottom of the pump cylinder, and a gap-sealing chamber is located between the transfer chamber and the pump cylinder. A gap-sealing assembly is located at the bottom of the plunger, including a connecting seat and a slip ring. The slip ring and the connecting seat are connected by multiple elastic connecting pieces. A flexible filter screen is installed in the gap between the slip ring and the connecting seat. This invention utilizes a flexible filter screen to completely seal the gap between the plunger and the gap-sealing chamber. During the downward movement of the plunger, solid particles are prevented from moving towards the outer wall area of ​​the plunger, avoiding collisions and damage to the outer surface of the plunger caused by harder solid particles. This further improves the service life of the plunger and the sliding sealing assembly, enhancing the long-term sealing effectiveness of the crankshaft pump.

A system comprises an actuation pump sub-system (APS) with an APS inlet to feed fuel from a fuel source into the APS, a first outlet for connecting the APS in fluid communication with an actuation sys

The utility model relates to a hydrostatic engineering machinery drive axle, which comprises an engine, a gearbox, a front transmission shaft, a front axle drive, a rear transmission shaft and a rear axle drive, the hydrostatic transmission system comprises a variable pump connected with the engine, a hydraulic motor connected with the input end of the gearbox and a reversing control valve connected between the variable pump and the hydraulic motor, and the variable pump, the reversing control valve and the hydraulic motor are connected to form a closed hydraulic loop; the front output shaft is provided with an off-axle clutch for controlling the front transmission shaft to be combined with or disconnected from the front output shaft, and the hydrostatic transmission system is connected with the off-axle clutch and controls the off-axle clutch to be combined with or disconnected from the front output shaft. The closed hydraulic loop is used for replacing a hydraulic torque converter, the transmission efficiency is improved, the energy consumption is reduced, the working condition adaptability of the whole machine is improved, and good fuel economy is achieved.