13312 results about "Reversing valve" patented technology

The invention belongs to the technical field of compressed natural gas filling, and particularly relates to an integrated hydraulic station which realizes high integration of an oil tank, plunger pumps, motors, a valve block, a cooler, an instrument and a sensor. The reversing function of hydraulic oil is provided through cooperation of an electro-hydraulic reversing valve and a proximity switch on a hydraulic cylinder, the functions of circulating heating of the low-temperature hydraulic oil, discharging of the high-pressure hydraulic oil and avoiding the hydraulic oil channeling back betweenthe double pumps are realized through cooperation of an unloading valve, a one-way valve and the electro-hydraulic reversing valve in the valve block, the high-pressure difference automatic stop function and the high-pressure gas discharging function are provided, combustible gas leakage and expansion deformation of the oil tank which cannot be recovered caused by high-pressure gas channeling back are avoided, the functions of low oil level monitoring alarm, temperature monitoring alarm and low oil temperature automatic circulating heating before starting of the hydraulic oil tank are provided, a three-way ball valve is adopted to replace an oil return valve block in the aspect of cooling oil return of the hydraulic oil, thus the oil return control function is realize, and the cost and space of the hydraulic station are also reduced.

The invention discloses a method for air conditioner defrosting, which comprises the following steps, first, a pipeline is added between an air discharge pipe of a compressor and an air inlet pipe of a condensator in advance, and a magnetic valve is arranged on the pipeline, second, the temperature of a coil pipe of the condensator and temperature of outdoor environment are detected, third, a defrosting operation is judged to be operated or not according to the temperature of the coil pipe of the condensator and the outdoor environment, if the defrosting operation is needed, the fourth step is executed, otherwise the second step is executed, fourth, the magnetic valve is controlled to open, the frequency of the compressor is controlled to reduce to a first predetermined value, a four-way change-over valve is controlled to change into a refrigerating operation, fifth, the compressor is controlled to make an indoor set convert up to a second predetermined value according to the first predetermined speed, sixth, the temperature of the condensator is judged to detect whether the temperature is satisfied for a condition of the defrosting withdrawal, if satisfied, the seventh step is operated, otherwise, the fifth step is operated, seventh, the magnetic valve is closed, the compressor is controlled to convert down to a third predetermined value according to the second predetermined speed, and the four-way change-over valve is controlled to change to a heat-producing operation. The invention provides a method for air conditioner defrosting, which solves the problem that the period of defrosting for an air conditioner is longer, and defrosting effect of the air conditioner is influenced.

The present invention relates to a directly-expanded type solar heat pump air conditioning and water-heating system, the directly-expanded type solar heat pump and ice cold-storage air conditioner are combined organically, and it is mainly formed from solar heat collector / evaporator, compressor, condenser, electronic expansion valve, four-way reverse valve, heat water storage tank, hot water tank, air conditioner tail end cover and system control component. The solar heat collector / evaporator adopts the plate type heat collector which has no cover plate and whose bottom is heat insulated and whose surface is coated with solar spectrum absorbing material, and the energy storage device adopts a closed pressure-bearing heat storage water tank whose interior is equipped with high-effective heat exchange equipment which can store heat in winter and can store ice in summer.

The invention relates to a live-working robot of a transformer substation. All signals of a control system are wirelessly transmitted, so that the operational safety performance is improved for operation personnel. The live-working robot comprises a work machine and a remote-control command vehicle; the work machine mainly comprises a power system, an actuating mechanism, a hydraulic control system and an operating system, the actuating mechanism mainly comprises a traveling mechanism, a rotating platform, a lifting platform and a hydraulic mechanical arm with six degrees of freedom, the lifting platform comprises a plurality of insulating arms, the rotating platform is mounted on the traveling mechanism, the lifting platform is connected with the rotating platform, and the hydraulic mechanical arm with six degrees of freedom is connected with the lifting platform; and the hydraulic control system comprises a hydraulic pump and is connected with the power system, and the hydraulic pump is further connected with an oil tank on the traveling mechanism and is respectively connected with a lower electromagnetic reversing valve bank A, a central crossover coupling, an upper electromagnetic reversing valve bank B, a mechanical arm hydraulic servo valve bank C, driving cylinders of the various insulating arms and a rotating motor by a distributing valve.

A shower assembly has a standing pipe, a connector, an overhead pipe, a fixed overhead shower head, a control valve, a handheld showerhead, a handheld showerhead bracket and a directional valve. The connector has a three-way passage. The directional valve is mounted inside the passage to direct water to flow selectively into either the overhead pipe or the standing pipe and has a tubular valve body, a valve rod, a primary disk and a secondary disk. The tubular valve body has a top opening, a bottom opening and a side opening communicating respectively with three ends of the passage. The valve rod is moveably mounted in the valve body. The primary disk and the secondary disk are mounted on the valve rod to selectively close the top opening or the bottom opening.

The invention discloses a thermostat dehumidification control method of an air conditioner. The air conditioner comprises a compressor, a condenser, an electronic expansion valve, an evaporator, a four-way reversing valve, an outdoor fan, an indoor fan, an indoor temperature sensor, an indoor humidity sensor and an outdoor temperature sensor; and the evaporator is divided into a heating section and a dehumidifying section by a dehumidifying electromagnetic valve. The dehumidifying operating mode of the air conditioner is divided into a cold room dehumidification control mode and a thermostat dehumidification control mode according to the difference between the temperature detected by the indoor temperature sensor and the temperature set by a remote controller. When the air conditioner is in the thermostat dehumidification control mode, the thermostat dehumidification control mode is further subdivided into three control areas according to the relative humidity detected by the indoor temperature sensor, thus the purposes of reducing the indoor temperature and keeping the temperature constant are achieved by controlling the frequency of the compressor, the rotation speed of the outdoor fan and various valves, and a conformable indoor environment is provided for the user.

A compact mobile vacuum boring, and excavation method comprising a device which will create a vacuum condition within a vacuum container and having a vacuum conduit to air convey a liquid and or solid particles into the vacuum container. The vacuum container air inlet & outlet conduit arrangement may also facilitate the separation of solids from the vacuumed air flow by producing a cyclone effect within the vacuum container. A circular cyclone effect is created within the vacuum container by the arrangement relationship between the inlet and outlet vacuum air conduits and baffles. As the air velocity slows, the solids precipitate out of the air and settle in the vacuum container. A housing with filters disposed within it is also adjacently mounted near the vacuum container in order to reduce the quantity of connecting conduits and facilitate a compact, efficient and clean interaction between the vacuum container and the filter housing. The vacuum container access door and the filter housing access door may be adjacently placed in near proximity to each other for user friendly access to empty and clean the vacuum container and filter house or a common door may access both. A compressible seal and conduit arrangement may be used as a quick disconnect between the vacuum producing means and the filter housing. A reversing valve arrangement may be used to back flow air through the filter. Sensors, data gathering, data logging and documentation of a service event may be included. The above systems may be mounted on a variety of mobile platforms.

The invention discloses an electronic expansion valve, which comprises an electrical control part and a mechanical part. The electrical control part comprises a bus signal reception / transmission module, a central processing module and a stepper motor driving module; wherein the bus signal reception / transmission module is used for receiving a bus control signal and transmitting the bus control signal to the central processing module; the central processing module is used for extracting valve opening information included in the bus control signal, generating a corresponding pulse control signalin combination with current position information of a stepper motor read from a data storage module, and outputting the pulse control signal to the stepper motor driving module; and the stepper motordriving module is used for driving the stepper motor to adjust the valve opening according to the pulse control signal. The invention also discloses a stepper motor and a reversing valve. The number of drive wires directly connected with a main control board can be reduced, the structure of the main control board can be simplified, and the manufacturing cost can be saved.

A heat and cooling system having an indoor air coil subcircuit, an outdoor air coil subcircuit, a geothermal subcircuit, and a control system for selectively operating the system in air-to-air heating, air-to-air cooling, geothermal heating, air-to-air defrost (optionally) and geothermal defrost modes. The various subcircuits may be connected to one another in parallel. The heating and cooling system may include a control system that permits refrigerant to be selectively routed through any two of the heat exchangers to provide the various modes of operation. In one embodiment, the control system may generally include a circuit having a single reversing valve, a plurality of check valves, a plurality of solenoid valves and a plurality of expansion devices.

The invention relates to a control method of a variable frequency air conditioner. The variable frequency air conditioner comprises a compressor, a four-way change valve, an outdoor heat exchanger, an outdoor fan, a throttling element, an indoor heat exchanger and an indoor fan, wherein an exhaust outlet of the compressor is provided with a compressor exhaust temperature sensor; an outdoor environment temperature sensor and an outdoor heat exchanger temperature sensor are arranged on the outdoor heat exchanger; and an indoor environment temperature sensor and an indoor heat exchanger temperature sensor are arranged on the indoor heat exchanger. When more than one temperature sensor breaks down, the variable frequency air conditioner can be operated according to the following control method of defaulting the detection temperature of the indoor environment temperature sensor to be 26 DEG C under a refrigeration, dehumidification or ventilation mode when the indoor environment temperature sensor breaks down. The invention can ensure that the air conditioner can be still normally used when partial sensors break down so as to ensure that a consumer furthest uses the variable frequency air conditioner with faults and reduce troubles caused by the faults of the air conditioner to the consumer.

A heat pump system (10) includes a compressor (20), a reversing valve (30), an outdoor heat exchanger (40) and an indoor heat exchanger (50) coupled via refrigerant lines (35, 45) in a conventional refrigeration circuit, and a refrigerant-to-water heat exchanger (60). In the air cooling with water heating mode, the air heating with water heating mode and the water heating only mode, water from a water reservoir (64), such as a storage tank or swimming pool, is passed through heat exchanger (60) in heat exchange relationship with refrigerant passing through an additional refrigerant line (27) that establishes a fluid flow path through the heat exchanger (60) into the refrigerant circuit intermediate the outdoor heat exchanger (40) and indoor heat exchanger (50). A refrigerant reservoir (70) may be provided for use in refrigerant charge control.

The invention provides an intelligent photovoltaic array washing car used for washing photovoltaic arrays of a large-scale ground photovoltaic power station. A washing head supporting and locating unit and a power unit are arranged on the head portion and the tail portion of a crawler base respectively, a water storage unit is arranged adjacent to the power unit, and a washing head unit is provided with range finder sensors used for measuring the distance between the washing head unit and solar cell panels; the washing head supporting and locating unit comprises a movable base capable of rotating and transversely moving and a working arm set provided with a main arm and an end arm, wherein the main arm and the end arm can pitch respectively; a water pump of a water supply unit is driven by a hydraulic motor; a computer is used as a control kernel of a main control module of an operation control unit; a pair of proportional directional valves of the hydraulic control unit controls two base crawler traveling motors, and other directional valves are electromagnetic directional valves controlled by the main control module. According to the intelligent photovoltaic array washing car, the position and the posture of the washing head unit relative to photovoltaic array panels and the position and the posture of a car body relative to the photovoltaic arrays can be automatically controlled, and the intelligent photovoltaic array washing car is intelligent, efficient, flexible in operation, high in adaptability, easy and convenient to operate, concise in structure and good in washing effect.

The invention provides a heat pump type air conditioning device which comprises an air conditioning main loop, an air supply loop and a defrosting device. The air conditioning main loop comprises a compressor, a four-way reversing valve, an outdoor heat exchanger, a throttling device, a flash evaporator, an expansion device and an indoor heat exchanger all of which are sequentially connected through a refrigeration pipeline, wherein a first connector of the four-way reversing valve is communicated with the outlet end of the compressor, a second connector of the four-way reversing valve is communicated with the outdoor heat exchanger, a third connector of the four-way reversing valve is communicated with the indoor heat exchanger, and a fourth connector of the four-way reversing valve is communicated with the inlet end of the compressor. One end of the air supply loop is connected with the flash evaporator, the other end of the air supply loop is connected with the compressor, and the air supply loop comprises air supply valves which are connected through a pipeline. The defrosting device is used for carrying out defrosting on the outdoor heat exchanger, and is a refrigerant heating device which is connected to the air conditioning main loop in series. According to the heat pump type air conditioning device, defrosting can be carried out under the condition that the compressor does not need to be stopped, defrosting is timely, and the structure is simple.

The invention provides a 2D (2-dimensional) hydraulic-power-assisted electro-hydraulic proportional reversing valve, which comprises a valve body, a valve core, a valve sleeve, a linear electro-mechanical converter and a compressive-torsional coupling, wherein the valve core, the compressive-torsional coupling and the linear electro-mechanical converter are coaxially connected; an output shaft of the linear electro-mechanical converter is fixedly connected with an input end of the compressive-torsional coupling; an output end of the compressive-torsional coupling is fixedly connected with the right end of the valve core; a sensitive cavity is formed by the left end of the valve core, the valve sleeve and a left cover plate; a pair of axisymmetric high pressure holes and a pair of axisymmetric low pressure holes are respectively formed on the surfaces of shoulders of the valve core in the sensitive cavity; a pair of axisymmetric sensing channels are arranged on the inner surface of the valve sleeve outside the sensitive cavity; and one end of each receptive channel is communicated with the sensitive cavity, and the other ends of the receptive channels cover areas between adjacent high pressure holes and low pressure holes. The 2D hydraulic-power-assisted electro-hydraulic proportional reversing valve not only has the characteristics of high flow rate, high working pressure, and the like of an ordinary pilot-control type electro-hydraulic proportional valve, but also fulfils a proportional control function like a direct-actuated proportional valve under the circumstance of zero pressure (pressure loss).

The invention discloses a differential energy recovery device and a method for a seawater desalination system. The differential energy recovery device comprises two hydraulic cylinders connected in parallel. A piston divides each hydraulic cylinder into two cavities. The piston is fixedly connected with a piston rod. A low-pressure raw water inlet is connected with two left cavities through liquid inlet valves. The left cavities are connected with a high-pressure raw water outlet through liquid drain valves. Two right cavities are connected with reversing valves. The reversing valves are connected with a high-pressure concentrated water inlet and are connected with a low-pressure concentrated drain outlet. The method is that high-pressure concentrated water coming from a reverse osmosis device is enabled to enter the right cavities of the two hydraulic cylinders through the reversing valves, and low-pressure raw water in the left cavities is pushed and pressurized to enter the reverse osmosis device. Since the direct pressurization principle of the hydraulic cylinders is used for the special design, one-time energy conversion is adopted and the pressure of high-pressure seawater after pressure exchange is larger than the pressure of concentrated saline water, the invention has the advantages that the pressurizing pumps are not required for pressurization once more, the energy conversion efficiency is high, the operating cost is saved and the energy consumption of the reverse osmosis system is further reduced.

The present invention provides a purifying apparatus, which is comprised of a mounting head, a reversing valve and a filter, wherein the mounting head has an inlet for connecting to the water supply pipes; said reversing valve includes a valve seat and a valve cartridge, therein the valve seat is fastened on the mounting head coordinating to the inlet and outlet, and the valve cartridge is set on the seat swinging between the valve seat and the mounting head coordinating to the inlet and the outlet of the mounting head; the replaceable filter is secured on the mounting head so as to mate the inlet and outlet of the filter to the inlet and outlet of the mounting head exactly, and by turning the filter the valve cartridge can be turned for controlling the inlet of the mounting head cutting in or off the inlet of the valve seat; and the inlet of the filter housing is connected to the outside wall of the filter element, and the outlet of it is connected to the center of the filter element; as tending to replace the filter, just need to twist off the filter cartridge to take it away from the mounting head and as the filter is turned down, the inlet of the valve cartridge is turned away from the inlet of the valve seat, so the water flowing way is blocked.

The invention discloses a reversing valve device. A first opening on a valve body is used for being communicated with a colorant container while a second opening on the same is used for being communicated with an injection pump, a valve core is arranged in an internal valve cavity of the valve body in a pivoted manner, an internal passage and a first colorant injection hole are arranged on the valve core, the internal passage is communicated with the second opening of the valve body, one end of the first colorant injection hole is communicated with the internal passage while the other end of the same is arranged on the peripheral surface of the valve core, a third opening on the valve body is formed on the inner wall of the internal valve cavity, a first passage is communicated with the first opening and the third opening, a fourth opening is formed on the lower end face of the valve body and communicated with the internal valve cavity, the first colorant injection hole can switch working positions along with rotating of the valve core, and the first colorant injection hole is exposed out of the fourth opening when being at a first colorant injection working position and communicated with the third opening when being at a non-colorant-injection position. By structural optimization, the phenomenon that colorant appears at a colorant outlet can be completely avoided. On the basis, the invention further provides a color mixer with the reversing valve device.

A heat pump system (10) includes a compressor (20), a reversing valve (30), an outdoor heat exchanger (40) and an indoor heat exchanger (50) coupled via refrigerant lines (35, 45, 55) in a conventional refrigeration circuit, a refrigerant to liquid heat exchanger (60), a refrigerant to liquid heat exchanger bypass valve (130), an outdoor heat exchanger bypass valve (230), and an indoor heat exchanger bypass valve (330). A controller (100) is provided to selectively control the respective positioning of the valves (30, 130, 230 and 330) between their respective open and closed positions so as to selectively configure the refrigerant circuit for operation in one of an air cooling only mode, an air cooling with liquid heating mode, an air heating only mode, an air heating with liquid heating mode, and a liquid heating only mode.

The invention discloses a hydraulic reversing valve, and particularly relates to an implementation method for search referral of doctors. The implementation method comprises the following steps: obtaining original data, extracting disease labels and referring to query keywords of users. The implementation method for search referral of doctors is high in searching speed, is high in accuracy and is high in degree of automation.

The invention discloses a heat recovery type multi-connection air condition unit, comprising at least one outdoor unit, a plurality of indoor units and at least one hot and cold converter. The outdoor unit comprises a compressor, an outdoor heat exchanger, a subcooler, two four-way reversing valves and three refrigerant pipelines; each indoor unit comprises an indoor heat exchanger; and the hot and cold converter comprises expansion valves and a bypass capillary, wherein the expansion valves control the on-off of a high pressure air pipe and a low pressure air pipe, and the bypass capillary is arranged between the high pressure air pipe and the low pressure air pipe. When the indoor unit connected with the hot and cold converter is used for heating, the expansion valve at the high pressure air pipe side is turned on and the expansion valve at the low pressure air pipe side is turned off to realize the connection of the air pipe of the indoor unit and the high pressure air pipe. When the indoor unit connected with the hot and cold converter is used for cooling, the expansion valve at the low pressure air pipe side is turned on and the expansion valve of the high pressure air pipe is turned off to realize the connection of the air pipe of the indoor unit and the low pressure air pipe. By the air condition unit, the combination of the units as well as the function of two-pipe heat pump air condition can be realized, and the common two-pipe heat pump air conditioner and the heat recovery type air conditioner capable of cooling and heating simultaneously are effectively combined.

The invention discloses a movable arm flow re-generation system with a potential energy recovery device for an excavator, and belongs to the technical field of engineering mechanical equipment. The system comprises a movable arm hydraulic cylinder, a three-position four-way servo valve, a controller, an overflow valve, an electromagnetic flow valve, a one-way valve, a variable output pump, an oil tank and an engine; the controller is electrically connected with the servo valve, the electromagnetic flow valve and the variable output pump; the three-position four-way servo valve is sequentially connected with a reversing valve and a hydraulic motor; the hydraulic motor is axially connected with a power generator; an output end of the power generator is electrically connected with a super capacitor; the outlet pressure of the hydraulic motor is controlled by the electromagnetic flow valve through the one-way valve of the motor; the reversing valve is connected with the oil tank; and the controller is electrically connected with the reversing valve, the power generator and the hydraulic motor. By the system, the optimal energy-saving state of the excavator can be realized during the falling of a movable arm, the energy consumption of the hydraulic system is reduced, the utilization ratio of the energy is improved, and the service life of the excavator is prolonged.

The invention discloses a dynamic pressure cavitation jet polishing device of colloidal flow and a method, relating to a polishing device and a method and aiming at solving the problems that the existing polishing method of the ultrasmooth surface has low processing efficiency and high cost, the adaptability of the work piece material is limited and the existing polishing device of the ultrasmoothsurface has complex equipment and high maintenance cost. The device is characterized in that a cavitation jet device is fixed on a bracket; the input end of the cavitation jet device is connected with an outlet of a first flow reversing valve by a pipeline. The method comprises the following steps: (1) the polished work piece is immersed with 10 to 200mm by the colloidal polished liquid level; (2) the oil pressure of the cavitation jet device is 0.5 to 15MPa; (3) the cavitation jet pressure is 0.5 to 15MPa; and (4) the cavitation jet device is arranged in colloidal polishing liquid, the cavitation jet device sprays to the work piece at the speed of 15 to 250m / s, and after polishing, the work piece is taken out, namely the polished work piece. The invention is used for ultraprecise and ultrasmooth polishing of optical glass, microcrystal glass, semiconductor materials and monocrystal materials.

The invention discloses a hydro-pneumatic suspension system and a wheeled vehicle with the same. The hydro-pneumatic suspension system comprises a left suspension oil cylinder, a right suspension oil cylinder, a left change valve, a right change valve, a first hydraulic locking structure and a second hydraulic locking structure. The left suspension oil cylinder and the right suspension oil cylinder are respectively provided with a rod cavity and a rodless cavity. The left change valve and the right change valve are three-position four-way valves and are respectively provided with a first oil opening and a second oil opening, a pressure oil opening connected with a pressure oil source and an oil return opening connected with an oil tank. The first hydraulic locking structure is connected between the left suspension oil cylinder and the left change valve. The second hydraulic locking structure is connected between the right suspension oil cylinder and the right change valve. The left change valve and the right change valve are respectively provided with a first state, a second state and a third state, wherein the first state enables the first working oil opening and the second working oil opening to be connected to the oil return opening; the second state enables the first working oil opening to be connected to the oil return opening and the second working oil opening to be connected to the pressure oil opening; the third state enables the first working oil opening to be connected to the pressure oil opening and the second working oil opening to be connected to the oil return opening. In the invention, the hydro-pneumatic suspension system and the wheeled vehicle can realize the active lifting of vehicle axles under the nonload bearing state.

The invention discloses an energy-saving shield segment assembling and positioning electro-hydraulic control system adopting a load-sensitive technology. The system comprises a motor, a variable pump, a two-position three-way proportional reversing valve, a variable cylinder, an overflow valve, a pressure reducing valve, a pressure compensating valve, a one-way valve, a multi-way valve, a balancing valve, a hydraulic lock, a hydraulic motor, a hydraulic cylinder, a moment rotation speed sensor, a displacement sensor and a pressure sensor. The multi-way valve with the pressure compensating valve in a segment assembling system is used for controlling the rotation speed of the hydraulic motor for driving the segment assembling machine to rotate and the moving speed of each hydraulic cylinder. The pressure sensor is used for detecting the pressure of a main oil passage of the system and the working pressure of each executer in real time; and a computer control unit is used for determining a variable pump control signal according to a system pressure signal, so that the displacement of the variable pump is changed with the load change so as to achieve load sensitive control. According to the invention, energy waste caused by continuous oil supply at the highest working pressure of the traditional system is avoided, the throttling loss and overflow loss are greatly reduced, and an obvious energy saving effect is obtained.

The invention relates to the technical field of agricultural machinery, in particular to an adjusting device used for a sowing depth automatic control system. A small frame is connected with a large frame through a four-bar linkage; a small land wheel is articulated on a wheel axle of a large land wheel and can freely float following the actual land surface relative to the small frame; a detection unit real-timely measures the distance of the small frame relative to the ground and the distance of a furrow opener relative to the small frame; two detected feedback signals are sent to a control part; the control part transfers the information to a hydraulic system after processing, controls a proportional reversing valve to operate and controls the reversion of an output shaft of a hydraulic motor; and an actuating mechanism drives a gear to rotate under the action of the output shaft of the hydraulic motor to realize the up-and-down movement of a slide block at the rear side of a shovel handle of the furrow opener along a guide rail and real-timely control and adjust the sowing depth. The device can realize real-time control and adjustment on the furrow opening depth, has high detection precision and high degree of automation, can improve the germination rate, promotes the crop growth and increases the crop yield.

The invention discloses an energy-conservation and low-impact hydraulic cylinder test testbed hydraulic control system. The system comprises a constant pressure variable pump, two electromotors, two electromagnetic unloading overflow valves, six check valves, two energy accumulators, an electrohydraulic proportional direction valve, two speed regulating valves, four ball valves, an oil supplementing pump, a proportional throttle valve, an electromagnetic reversing valve, a loading hydraulic cylinder, six pressure sensors, two temperature sensors, a displacement sensor, a force sensor, two travel switches, six pressure measuring connectors, six pressure gages, a heater, a liquid level liquid temperature gage, a filter and an oil tank. The energy-conservation and low-impact hydraulic cylinder test testbed hydraulic control system has the advantages that stable energy is provided for low-impact control over the speed of a tested hydraulic cylinder while energy is conserved, low-impact stable control over the loading force is achieved, meanwhile, the actual work condition that loads of the hydraulic cylinder probably change continuously in work can be simulated, all the work conditions of the loads of the hydraulic cylinder can be simulated, and power input is reduced.