2802results about "Servomotors" patented technology

The invention discloses a deep sea underwater integrated electro-hydraulic actuator system adopting pump and valve combination. The deep sea underwater integrated electro-hydraulic actuator system comprises a hydraulic cylinder, a pump control assembly and a valve control assembly. The pump control assembly comprises a metering pump, a first switch valve and a second switch valve; the valve control assembly comprises a large-flow proportional valve, a small-flow proportional valve, a deep sea compensation energy accumulator and a third switch valve. The metering pump, the first switch valve and a rod cavity of the hydraulic cylinder are sequentially connected through a pipeline, the metering pump, the second switch valve and a rodless cavity of the hydraulic cylinder are sequentially connected through a pipeline, the metering pump, the third switch valve and the deep sea compensation energy accumulator are sequentially connected through a pipeline, and the rodless cavity of the hydraulic cylinder is connected with the large-flow proportional valve and the small-flow proportional valve through pipelines. Two control modes of the actuator can be completed, large-flow control is achieved through the pump control assembly, high efficiency and energy conservation are achieved, flow needed by maintenance is supplied to a rodless cavity of the actuator through the valve control assembly via the large-flow proportional valve and the small-flow proportional valve, and posture keeping and emergency action are achieved.

A constant-flow control valve group, an auxiliary arm control module, a complete hydraulic system, and a crane. The constant-flow control valve group comprises: a cartridge valve; a cartridge reversing valve, comprising a working oil port on one side and a main oil return port and a reversing valve oil inlet selectively connected to the working oil port on the other side, the working oil port being connected to a control oil port of the cartridge valve, and the reversing valve oil inlet being connected to a main oil inlet of the cartridge valve; and a feedback on-off valve, disposed in a working feedback oil path connected between the main oil inlet of the cartridge valve and a main feedback oil port of the constant-flow control valve group. The auxiliary arm control module comprises the constant-flow control valve group and a main reversing valve. The complete hydraulic system comprises the auxiliary arm control module and an auxiliary arm luffing cylinder, and may further comprise a load-sensitive oil pump and a main valve. The present application can achieve the effect of directly connecting an auxiliary arm hydraulic system to an existing complete hydraulic system as a sub-module without altering the original system.

The utility model discloses a hydraulic walking control system and a high-altitude operation vehicle. The system comprises a walking pump, a first flow distributing and collecting valve, a second flow distributing and collecting valve and walking motors. A port A of the walking pump is connected with a third port of the first flow distributing and collecting valve and a third port of the second flow distributing and collecting valve, and a port B of the walking pump is connected with a port B of the left front walking motor, a port B of the left rear walking motor, a port A of the right front walking motor and a port A of the right rear walking motor. A fourth port of the first flow distributing and collecting valve is connected with a port A of a left front walking motor, and a second port of the first flow distributing and collecting valve is connected with a port A of a left rear walking motor; a fourth port of the second flow distributing and collecting valve is connected with a port B of the right front walking motor, and a second port of the second flow distributing and collecting valve is connected with a port B of the right rear walking motor. According to the utility model, the problem that the walking effect is influenced due to the change of flow and pressure caused by slipping during walking is avoided.

The invention discloses a multi-mode hydraulic system for synchronous pushing and splicing shield tunneling track deviation rectification. The multi-mode hydraulic system comprises a shield body, a pushing side hydraulic cylinder, a load side hydraulic cylinder, a counter-force plate and a follow-up supporting device. Six hydraulic cylinders are arranged on the propelling side and evenly distributed on the inner side of the shield body. The loading side is provided with four hydraulic cylinders which are uniformly distributed on the inner side of the shield body; the left sides of the ten hydraulic cylinders are connected with the shield body through hooke joints, and the right sides are connected with the counter-force plate through hooke joints; wherein a passive loading mode is adopted on the loading side; five propulsion system control loops are provided on the propulsion side, namely proportional pressure reducing valve control, proportional overflow valve and proportional speed regulating valve parallel control, proportional pressure reducing valve and proportional speed regulating valve load port independent control, proportional overflow valve and proportional speed regulating valve load port independent control and proportional speed regulating valve load port independent control. By the adoption of the technical scheme, various control requirements of pressure control and pressure flow compound control can be met.

The invention provides a multi-pump zero-displacement hydraulic agile control system and a control method thereof. The system is composed of a hydraulic system, a mechanical system and an electric control system. According to the control method, a multi-pump zero-displacement switching mechanism and a deep reinforcement learning strategy based on an Actor-Critic architecture are fused, the effective oil supply amount is adjusted by dynamically starting and stopping part of hydraulic pumps, a servo motor rotating speed instruction is output in real time in combination with a neural network, and the strong coupling dynamic relation between sliding block displacement and the angle of a swing rod is coordinated. The system switches part of the pumps to a bypass state when approaching balance so as to reduce energy consumption, and starts all the pumps to guarantee recovery capacity when greatly deviating. According to the technical scheme, on the premise of not depending on an accurate mathematical model, agile, stable and energy-saving control over the inverted pendulum type under-actuated system can be achieved.

A hydraulic drive apparatus includes a hydraulic pump that discharges a working fluid; a flow dividing valve that divides a pump passage connected to the hydraulic pump into first and second passages, and changes an opening degree of each passage according to a signal that is input to the flow dividing valve; a travel system hydraulic circuit that is connected to the first passage and controls a flow of the working fluid to a travel motor; a loading system hydraulic circuit that is connected to the second passage and controls a flow of the working fluid to a loading actuator; a pressure sensor that detects a pressure supplied to the travel motor; and a control device that controls, by outputting the signal to the flow dividing valve, the opening degree of the first and second passages according to the pressure detected by the pressure sensor.

The invention belongs to the technical field of aircraft hydraulic pipeline pressure pulsation and vibration suppression design, and particularly relates to an aircraft hydraulic pipeline pressure pulsation and vibration suppression system and a design method thereof.The aircraft hydraulic pipeline pressure pulsation and vibration suppression system comprises a vibration absorber, a pressure accumulator, a rubber single-hole pipe clamp and a metal single-hole pipe clamp; the vibration absorber, the pressure accumulator, the rubber single-hole pipe clamp and the metal single-hole pipe clamp are arranged on the hydraulic pipeline, and the rubber single-hole pipe clamp and the metal single-hole pipe clamp are connected to the machine body structure through the pipeline support. An inlet of the hydraulic pipeline is connected with an outlet of the hydraulic pump, and an outlet of the hydraulic pipeline is connected with an inlet of the hydraulic load. The vibration absorber is arranged at an inlet of the hydraulic pipeline, close to an outlet of the hydraulic pump and located on the upstream of the one-way oil supply valve, and the pressure accumulator is arranged between the high-pressure oil filter and the hydraulic load; a plurality of rubber single-hole pipe clamps and a plurality of metal single-hole pipe clamps are distributed on the hydraulic pipeline.

The invention provides an impact rotary drilling hydraulic control system of a dinting machine, which belongs to the technical field of hydraulic control systems and comprises a variable pump, a pilot oil source control valve group, a proportional multi-way valve, a shuttle valve I, a one-way pressure reducing valve, a shuttle valve II, a drilling machine pilot handle group, an impact rotary drilling machine, a bidirectional hydraulic lock and a drilling machine feeding oil cylinder. According to the hydraulic control system for percussive rotary drilling of the dinting machine, the percussive rotary drilling machine can perform stepless speed regulation between two speeds, high-frequency percussive or low-frequency percussive operation can be flexibly used according to rock stratum and geological working conditions, the application range of equipment is greatly widened, and the hydraulic control system can be used for rock stratums with high hardness, weathered rock stratums and hard and brittle geology. And during low-frequency impact operation, one-key linkage operation can be realized, namely, the functions of feeding, rotating and impacting of the drilling machine can be completed by operating the impact pilot handle.

The utility model discloses a hydraulic logic control system for a sidesway distance adjusting fork. Comprising an oil pump, a safety valve, a first reversing valve plate, a logic control valve block, a first hydraulic control one-way valve, a first three-way pipe, a right pallet fork distance adjusting oil cylinder, a left pallet fork distance adjusting oil cylinder, a first overload valve, a second hydraulic control one-way valve, a second three-way pipe, a third three-way pipe, a third hydraulic control one-way valve, a throttling valve, a second reversing valve plate and a second overload valve. The logic control valve block comprises a second hydraulic control one-way valve, a third hydraulic control one-way valve, a throttling valve and a second overload valve, and the second hydraulic control one-way valve, the third hydraulic control one-way valve, the throttling valve and the second overload valve are communicated through pipelines. And the first reversing valve plate is communicated with the second reversing valve plate. According to the hydraulic logic control system for the laterally-moving distance adjusting fork, the purpose of hydraulic oil way regulation and control is achieved through the arrangement of the structure.

The invention provides a hydraulic closed-loop tilling depth control system based on multi-sensor fusion in order to solve the problems that traditional tilling depth control is low in precision, poor in stability and the like. The system collects data through an inclination angle sensor, a displacement sensor, a posture sensor and the like, and after fusion processing, a hydraulic cylinder drives a parallel four-bar mechanism to adjust the tilling depth of the subsoiler. The system has three innovations: firstly, a dynamic model is constructed by using multi-source sensor cooperation and sliding mode variable structure control, the anti-interference capability is improved by combining a control strategy, and accurate tilling depth control is dynamically realized according to soil conditions; 2, a parallel four-bar mechanism is mechanically designed to be combined with hydraulic drive, terrain interference is eliminated by utilizing mechanism characteristics, and the control precision and unbalance loading resistance are enhanced; and thirdly, a bidirectional hydraulic lock and a manual-electric dual-mode oil way are adopted for hydraulic pressure, so that reliable tilling depth control and continuous operation are guaranteed. The three innovations are fused, and a high-precision, strong-stability and ultra-reliable tilling depth control solution is provided for saline-alkali soil agriculture.

A working machine includes: at least one support member connectable to a work attachment to do work by making contact with an object to be contacted; at least one hydraulic cylinder to move the work attachment connected to the at least one support member, a rod-side pressure detector to detect a rod-side hydraulic pressure of hydraulic fluid in communication with a rod-side fluid chamber of the at least one hydraulic cylinder; a bottom-side pressure detector to detect a bottom-side hydraulic pressure of hydraulic fluid in communication with a bottom-side fluid chamber of the at least one hydraulic cylinder; and a controller to calculate a relationship in pressure between the rod-side hydraulic pressure and the bottom-side hydraulic pressure and evaluate, based on the calculated relationship in pressure, a contact state which is a state of contact of the work attachment with the object.

The invention relates to the technical field of hydraulic control, and discloses a hydraulic motor constant torque self-adaptive PID (Proportion Integration Differentiation) control system which comprises a controller and a hydraulic driving unit, the controller performs frequency domain separation on the pressure signal by using a signal preprocessing module, and extracts an average pressure difference representing the driving force and a ripple amplitude representing the fluid rigidity; the state observation module estimates an instantaneous volume elastic modulus based on the ripple amplitude, corrects a compression item in a flow continuity model by using the elastic modulus, and calculates an instantaneous leakage coefficient of the motor in real time; the self-adaptive control module establishes dynamic mapping of PID gain and physical parameters, the proportional gain is adjusted by using a leakage coefficient to match system damping, the integral gain is adjusted by using a volume elastic modulus to adapt to inherent frequency, and a control instruction is synthesized by combining feedforward compensation. According to the method, the problem of model mismatch caused by oil characteristic change and motor abrasion is effectively solved, and the whole-life-cycle control precision of the system is improved.

The invention discloses a hydraulic system and hydraulic equipment for self-adaptive buffering under impact. Comprising a hydraulic motor used for driving an execution element, a closed type pump set used for driving the hydraulic motor, and a first oil way used for connecting an oil outlet of the closed type pump set with an oil inlet of the hydraulic motor. The second oil way is used for connecting an oil outlet of the hydraulic motor with an oil inlet of the closed type pump set; the self-adaptive cushion valve set is used for weakening pressure impact of the oil way on the high-pressure side and avoiding pressure suction of the oil way on the low-pressure side; oil inlets and oil outlets of the two self-adaptive buffer valve groups are oppositely connected with the first oil way and the second oil way in parallel; the hydraulic closed system is ingenious in structure, the self-adaptive buffer valve group can weaken pressure impact of a high-pressure side oil way, meanwhile, the situation that the pressure of a low-pressure side is rapidly reduced or even air is sucked is avoided, normal work of the hydraulic closed system is guaranteed, and the service life of the hydraulic closed system and all elements can be prolonged.

A hydraulic circuit includes a first oil path, a second oil path, a hydraulic control circuit, a third oil path, a check valve, and a relief valve. The first oil path links to a discharge port of a first oil pump. The second oil path links to a discharge port of a second oil pump. In the hydraulic control circuit, a first regulator valve is disposed downstream of a confluence point of the first oil path and the second oil path. The third oil path connects a suction port of the first oil pump and a strainer. The check valve is provided in the third oil path and restricts a movement of oil toward the strainer side. The relief valve is provided in the third oil path and discharges oil in the third oil path to an outside when a pressure in the third oil path exceeds a reference pressure.

The invention discloses a pinch roll gap cascade control system with an automatic calibration function. The pinch roll gap cascade control system comprises a hydraulic module, a detection module and an upper computer, the hydraulic modules are arranged on the two sides of the pinch roll device. The detection module is arranged on the hydraulic module; the upper computer is connected with the hydraulic module and the detection module. The invention further discloses a pinch roll gap cascade control method with the automatic calibration function. The invention provides a control system which is good in pinch roll gap adjusting effect and considers automatic calibration in the high-precision steel plate production process.

The invention discloses a hydraulic pump dynamic flow control method and system based on load feedback, and relates to the technical field related to hydraulic pumps, and the method comprises the steps that the load pressure of a hydraulic pump is monitored in real time, a first load pressure signal is generated, and a target flow parameter is set; a load pressure-flow mapping graph is constructed through dynamic mapping; dynamically responding to generate load compensation parameters to carry out load control on load pressure; and deviation calculation is carried out on the target flow parameter based on the second load pressure signal, a flow deviation signal is obtained to carry out dynamic flow control on the hydraulic pump, a flow displacement control result is fed back to carry out real-time correction on the load compensation parameter, and a flow closed-loop backtracking control channel is constructed. The technical problems that in the prior art, the flow control response of the hydraulic pump is lagged under the variable load working condition, the control precision is insufficient, and the energy efficiency is low are solved, and the technical effects that the dynamic response speed, the control precision, the stability and the energy efficiency of flow control of the hydraulic pump are improved are achieved.

A pneumatic system for a vehicle, comprising an air compressor for pressurizing an air tank. A flow passage extending from compressor is bifurcated to a first valve and to a second valve. The first valve has a first state preventing air from passing to the air tank, and has a second state allowing air to pass to the air tank. In a first mode of operation of the pneumatic system, the first vale is in said first state and the second valve controls air flow from the compressor to ambient environment. The second valve is configured to change to, or remain in, an open state when the pressure of the air upstream of the second valve is higher than a predetermined threshold, and to change to, or remain in, a closed state when the pressure of the air upstream of the second valve is lower than the predetermined threshold.

The invention discloses a hydraulic system for preventing reversing cutoff of a cone valve type filling industrial pump. The hydraulic system comprises a first oil pump set, a second oil pump set, a main oil cylinder set, a first pressure valve suction valve oil cylinder set, a second pressure valve suction valve oil cylinder set, a reversing valve set and a pipeline. The first oil pump set is composed of a first oil pump, a second oil pump and a first constant-pressure oil pump set. The second oil pump set is composed of a third oil pump, a fourth oil pump and a second constant-pressure oil pump set. The first pressure valve suction valve oil cylinder set comprises a first pressure valve oil cylinder and a first suction valve oil cylinder, and the second pressure valve suction valve oil cylinder set comprises a second pressure valve oil cylinder and a second suction valve oil cylinder. The reversing valve group comprises first to sixth reversing valves. According to the reversing cutoff prevention hydraulic system of the cone valve type filling industrial pump, through unique structural design and assembly configuration, the cutoff problem in the reversing process is effectively solved, continuous and stable operation of the system is ensured, and the working efficiency and reliability of the industrial pump are improved.

A vacuum system comprises at least a pneumatic positioning device comprising a mount configured to hold an effecting element and a pneumatic actuator connected to the mount. A control valve is connected to the pneumatic actuator and to a fluid supply. A fluid sensor measures the pressure of the pneumatic actuator. A method includes applying a controlling signal to the control valve to vary the pressure of the pneumatic actuator and move the mount from a starting position to an end position, monitoring the pressure of the pneumatic actuator by the fluid sensor, determining when the mount arrives at the end position, and deriving the controlling parameters based on processing a set of observed parameters, wherein the set of observed parameters comprises at least the controlling signal, the varying pressure, and arrival information of the mount at the end position.

The invention belongs to the technical field of lifting tools, and particularly discloses a lifting device oil way system, a lifting device, a jack, a pressing machine and a crane. The oil way system of the lifting device comprises a lifting oil cylinder, an oil tank, a first oil inlet way, a second oil inlet way and an oil return pipeline, the first oil inlet path is an oil inlet path of the gear pump assembly; and the second oil inlet path is an oil inlet path of the plunger pump assembly. When the lifting device is in the no-load or low-pressure condition, the gear pump assembly can rapidly pump in much hydraulic oil with small pressure so that the lifting device can rapidly ascend or descend, the defect that in the prior art, the displacement speed of a hydraulic lifting pump is low under the no-load or low-pressure condition is overcome, and the user experience is improved; when the hydraulic lifting pump is in a high-pressure condition, the plunger pump assembly can pump high-pressure hydraulic oil into the lifting oil cylinder so that the lifting oil cylinder can ascend or descend slowly, the lifting device can move slowly, and the normal use requirement of a user is met.

The invention provides a hydraulic control system, garbage compression equipment and a control method, and relates to the technical field of garbage treatment equipment. The hydraulic control system comprises a compression oil cylinder, an oil tank, an oil pump and a control valve group, the compression oil cylinder is used for driving a load to move in a first direction, and the compression oil cylinder is provided with a rod cavity and a rodless cavity; wherein an included angle is formed between the first direction and the horizontal direction. The control valve group is connected to the oil pump, the oil tank, the rod cavity and the rodless cavity. When the control valve set is in the first state, output of the oil pump can be stopped, hydraulic oil flows out of the rod cavity and flows to the rodless cavity at the same time, and therefore the compression oil cylinder extends under the load gravity. Therefore, in the garbage compression process, energy waste can be reduced, the extension speed of the compression oil cylinder can be increased, and then the garbage compression efficiency is improved.

The disclosure discloses an oil circuit system, a lifting device, an electric jack, a press, a crane, and a tire mounting / dismounting and transport apparatus. The oil circuit system comprises a lifting oil cylinder, the tank, the first oil feed line, the second oil feed line, the oil inlet / outlet line, the pressure relief line, the oil return line, the first valve, the second valve; the first oil feed line is the gear pump assembly oil feed line; and the second oil feed line is the plunger pump assembly oil feed line. Under no-load or low-pressure conditions of the lifting device, the gear pump assembly can quickly pump a larger volume of low-pressure hydraulic oil, enabling quick lifting or lowering of the lifting device. Under high-pressure conditions, the plunger pump assembly can quickly pump higher pressure hydraulic oil to the lifting oil cylinder to enable slow lifting or lowering.

The invention provides a multi-cylinder synchronous accurate control method for a hydraulic jacking system of a tower crane, and belongs to the technical field of tower cranes. A pressure sensor and a displacement sensor are mounted on each hydraulic cylinder of a hydraulic jacking system of the tower crane, and a force sensor is arranged at a key position of a tower body, so that a multi-parameter real-time monitoring network is established; an improved Gaussian kernel function nonlinear matrix mapping algorithm is adopted to calculate a pressure deviation coefficient and a displacement synchronization metric value between hydraulic cylinders, the pressure adjustment processing frequency is dynamically adjusted according to the pressure deviation coefficient value, and self-adaptive load balancing control is achieved through tower body stress unbalance threshold value calculation and stress adjustment gain calculation. And finally, the flow distribution of each hydraulic cylinder is adjusted through a proportional valve, and the convergence of the system is ensured by utilizing Lyapunov stability analysis, so that the technical problem that the multi-cylinder synchronous control of the hydraulic jacking system of the tower crane is not accurate enough is solved.

A hauling vehicle includes a steering circuit having a steering cylinder steered by pressure oil from a hydraulic source, a steering valve that controls the flow of pressure oil to the steering cylinder, and an accumulator that stores pressure oil from the hydraulic source and can supply it to the steering cylinder via the steering valve. The steering circuit is connected to the hydraulic source and the hydraulic fluid tank via a composite control valve. The composite control valve has a first position for communication between the steering circuit and the hydraulic source and blocking communication between the steering circuit and the hydraulic fluid tank, and a second position for communication between the steering circuit and the hydraulic source and communication between the steering circuit and the hydraulic fluid tank. The composite control valve has a throttle in the oil passage that connects the steering circuit in the second position with the hydraulic fluid tank.

The invention discloses a control method and system for a hydraulic system of a tunnel secondary lining trolley, and the method comprises the steps that when the tunnel secondary lining trolley stops and does not work, a PLC obtains a self-checking starting instruction, and outputs a driving signal to each electromagnetic valve; the electromagnetic valve is driven to act to enable the corresponding oil cylinder to generate detection-level displacement which can be collected by the displacement sensor and does not change the working state of the corresponding template; the PLC associates and matches a driving signal output time sequence with an acquired displacement information acquisition time sequence, and establishes an actual mapping relation between a digital quantity output channel and an analog quantity feedback channel to identify the connection state of the oil pipe and the electromagnetic valve; and the PLC updates the association logic of the remote controller instruction and the digital quantity output channel based on the actual mapping relation. According to the scheme, the actual channel mapping relation is established through self-checking, the control logic is updated, the problem of control failure caused by connection dislocation of the oil pipe and the electromagnetic valve is solved, it is ensured that the remote controller can accurately control the target oil cylinder, and the control reliability of a hydraulic system and the operation safety of a trolley are improved.

The invention belongs to the field of engineering machinery, and discloses a forklift loader and a fork hydraulic system.The fork hydraulic system comprises a first oil cylinder and a second oil cylinder, rod cavities between the first oil cylinder and the second oil cylinder are communicated with each other, a rodless cavity of the first oil cylinder is connected with a first sidesway working oil way, and a rodless cavity of the second oil cylinder is connected with a second sidesway working oil way. A rodless cavity of the second oil cylinder is connected with a second lateral displacement working oil way; and a multi-way valve to which the first side shift working oil path and the second side shift working oil path are hydraulically connected. The two oil cylinders can be driven to generate synchronous transverse movement on the opposite sides, and therefore synchronous lateral movement hydraulic driving is achieved. The distance between the fork knives of the pallet fork is adjusted in a non-manual mode, goods can be conveniently taken by the pallet fork, the left-right position adjustment of heavy goods loaded by the pallet fork on the pallet fork portal frame can be achieved, and the heavy goods can be conveniently and accurately stacked.

The invention discloses an electric forklift gantry synchronous inclination system and an inclination system control method, and relates to the technical field of vehicle engineering and electrical control, and the method comprises the following steps: establishing a time-frequency phase-locked observation baseline, and calibrating an abnormal trigger window by collecting a pressure wave change track of the gantry synchronous inclination system under a reverse pressure bearing condition; generating a pressure wave characteristic fingerprint and a time delay matrix as dynamic references for resonance path identification; and according to the pressure wave characteristic fingerprints and the time delay matrix, inverting a hydraulic pipeline reflection topology, identifying a pressure energy concentration area, extracting a resonance source anchor point, constructing a wave energy distribution diagram, and forming a space positioning basis of the standing wave risk. According to the method, hydraulic standing wave risk modeling and boundary extraction are achieved through time-frequency observation and resonance path recognition, a standing wave damping structure is constructed in combination with the phase conjugate test and track shaping technology, steady-state damping and high-precision synchronous inclination control of the portal under reverse pressure bearing are achieved, and the system stability and operation safety are improved.

The invention relates to the technical field of multi-cylinder synchronous control, in particular to an electro-hydraulic-mechanical dual-redundancy high-precision execution method and system for multi-cylinder synchronous control. The method comprises the following steps: acquiring design data of the multi-cylinder hydraulic jacking equipment, and constructing a multi-cylinder operation simulation model based on a geometric structure and the design data; estimating the dynamic load overrun condition of the gate, detecting the distortion increase condition of the gate structure, and monitoring the increase trend of the gate to overcome the resistance; the multi-cylinder operation simulation model is analyzed according to the gate overcome resistance increasing condition, the local cylinder mechanical degradation increasing trend is determined, and hydraulic oil flow control distortion data is detected according to the local cylinder mechanical degradation increasing trend; detecting multi-cylinder operation stroke deviation according to local cylinder body mechanical degradation and hydraulic oil flow distortion conditions, identifying a multi-cylinder synchronization abnormal trend, and performing optimization processing to obtain multi-cylinder synchronization optimization data; through multi-cylinder synchronous control, multi-cylinder synchronous control is more efficient.

An electrohydraulic system for a work machine includes a pump, a motor fluidly coupled to the pump, a subassembly driven by the motor, and a rate-control valve fluidly coupled to the pump and the motor. The rate-control valve is movable through a range of positions. A present speed of the motor is proportional to a present position of the rate-control valve. The present position of the rate-control valve is adjustable by varying a current supplied to the rate-control valve. The supply of current to the rate-control valve is adjusted based on the difference between the present speed of the motor and a target speed of the motor.

The utility model discloses an integrated bidirectional hydraulic pump station for a car arrester in a tank, which comprises a valve block, a bidirectional hydraulic pump, a motor, an oil tank, a car arrester driving oil cylinder, overflow valves and one-way valves, a left oil way and a right oil way are arranged in the valve block, the left oil way is provided with a first overflow valve, a first one-way valve and a fifth one-way valve, and the fifth one-way valve is a hydraulic control one-way valve. A second overflow valve and a second one-way valve are installed on the right oil way, and the second one-way valve is a hydraulic control one-way valve and is controlled by the oil pressure of the left oil way; an oil port A1 of the two-way hydraulic pump is connected with a piston cavity oil port of the car arrester driving oil cylinder through a left oil way, and an oil port B1 of the two-way hydraulic pump is connected with a piston rod cavity oil port of the car arrester driving oil cylinder through a right oil way. The left oil way is connected with the oil tank through a fifth one-way valve, and the fifth one-way valve is used for releasing additional backpressure generated in a piston cavity in the process that the two-way hydraulic pump drives a piston rod of the car arrester driving oil cylinder to retract. According to the utility model, the power consumption is reduced, the energy is saved, and the reliability of the system is improved.