1194 results about "Proportional valve" patented technology

The invention relates to the technical field of flow measurement and control, and particularly discloses a cheese filling flow real-time calibration control method and system.The cheese filling flow real-time calibration control method comprises the following steps that working condition information of cheese in a filling pipeline is collected in real time, and the working condition information comprises the temperature, the pressure, an original flow signal, the pump rotating speed and the proportional valve opening degree; dynamically selecting a filtering order according to the signal-to-noise ratio of the original flow signal, and outputting the filtered flow; and based on the acquired working condition information, predicting the dynamic viscosity of the cheese in real time through a neural network, fitting a flow-working condition relation function and calculating a target flow value. The signal-to-noise ratio of an original flow signal is dynamically adapted to optimize filtering processing, signal distortion caused by interference such as temperature drift and mechanical vibration is effectively eliminated, and the flow detection precision is improved; by means of the neural network, the dynamic viscosity of cheese is predicted in real time, the model is dynamically adjusted, the problems that traditional viscosity estimation lags behind, and the batch adaptability is poor are solved, and an accurate basis is provided for flow target value calculation.

The invention relates to the technical field of automatic control, in particular to a multi-parameter cooperative control method and device for a clamping system of a precision boring and milling machine. According to the method, an industrial camera is used for collecting and processing a workpiece image and extracting visual features, and the visual features are fused with process parameters of a workpiece and geometric distribution parameters of a workpiece key area obtained from a process database; generating a comprehensive state vector; based on the vector, outputting a target clamping force adjustment coefficient by a pre-trained MLP decision model, and calculating a final target clamping force in combination with a safe clamping force range; in the main clamping stage, vibration, temperature and pressure signals are synchronously collected, multi-modal disturbance characteristics are extracted, observation vectors are constructed, the observation vectors are input into a preset fuzzy rule base for reasoning, and compensation activation factors are obtained; and finally, a current correction instruction is dynamically generated according to the clamping force deviation and the compensation factor, and an electro-hydraulic proportional valve is driven to achieve accurate compensation. According to the invention, the stability and the machining reliability of the clamping system are obviously improved.

The invention discloses a micro proportional valve gradient composite coating and a preparation method thereof, and belongs to the technical field of micro proportional valve surface strengthening manufacturing. Aiming at the corrosion-resistant and wear-resistant requirements of the micro proportional valve under the working conditions of strong corrosion, multiple impurities and high pressure difference, the interface strengthening and corrosion-resistant and wear-resistant performance optimization of a metal matrix and a functional coating are combined, and metal / ceramic / polymer gradient material design, spraying parameter suitability research and a coating porosity / bonding strength control method are covered; the valve core and valve seat protection device is suitable for high-efficiency protection technical systems of valve cores and valve seats of precise instruments such as gas chromatographs and mass spectrometers.

The invention provides a small-capacity air bag blood pressure detection system and a precise pressure control method thereof. A micro air pump is communicated with an air inlet of a small-capacity air bag through a pipeline, and a linear proportional valve is arranged on an air release opening of the small-capacity air bag and used for controlling the opening, closing and flow of the air release opening of the small-capacity air bag; the miniature air pump is normally opened and provides stable-flow input air flow for the small-capacity air bag, the valve opening degree of the linear proportional valve is changed by executing a self-adaptive differential constant-pressure control algorithm, then the air release speed of an air release opening of the small-capacity air bag is changed, and pressure adjustment of the small-capacity air bag is achieved by changing the difference between the inflation speed and the deflation speed. According to the invention, rapid pressure stabilization can be realized, and pressure overshoot is hardly generated after the pressure is stabilized; the pressure control precision of 1mmHg at any pressure regulation step length is realized; the problem that the traditional single-parameter closed-loop control cannot meet the precise control of each pressure interval is solved; the production cost is further reduced, and the out-of-hospital scene adaptability and the popularization degree of the equipment are improved.

The invention discloses a control method and device of a hydraulic synchronous lifting device, a computer program and a storage medium, belongs to the technical field of ship manufacturing, and particularly relates to a control method of a hydraulic synchronous lifting device for ship assembly. In order to solve the problems of low synchronization precision, slow dynamic response, insufficient error compensation, poor environmental adaptability and the like of the existing control method of the hydraulic synchronous lifting device, the invention provides the control method of the hydraulic synchronous lifting device, which comprises the following steps of: acquiring a target height, a maximum inclination angle, a maximum deviation and a preset proportional valve opening; the actual heights of the four main jacking oil cylinders are obtained in real time, the average value and the inclination angle are calculated, whether the target height is reached or the maximum inclination angle is exceeded is judged, if not, the deviation of each oil cylinder is calculated, and the opening degree of the corresponding proportional valve is adjusted when the deviation is exceeded, and synchronous lifting is ensured. The device is suitable for the fields of ship building and maintenance, in-place and leveling of bridge precast beam bodies and extremely high requirements for lifting precision and safety.

The invention relates to the technical field of response time testing of electro-hydraulic proportional valves, and discloses a response time testing method and system of an electro-hydraulic proportional valve, and the method comprises the steps: collecting multi-point pressure, step response, pipeline length and medium parameters, and unifying the time reference to obtain an original pressure sequence; constructing an inverse filter spectrum to remove damping interference so as to recover a sharp peak value; lagging offset is calculated according to pipeline and medium parameters, time delay compensation is carried out, and an alignment sequence is obtained; intercepting a non-stationary segment to eliminate residual delay deviation; constructing a response dynamic data set, extracting harmonic frequency domain representation, and reconstructing a pressure sequence through inverse transformation and superposition of compensation factors; and calculating a deviation integral quantity, adjusting a dynamic compensation parameter, performing weighted correction, and outputting an optimized reconstruction response sequence. According to the method, accurate reconstruction of the real pressure response of the proportional valve can be realized, so that the accuracy and the reliability of response time testing are improved.

The invention relates to the technical field of hoisting construction dynamic safety assessment, and particularly discloses a hoisting construction dynamic safety assessment method, which comprises the following steps of: acquiring operation parameters of a hoisting system in real time through a multi-modal sensor array, and generating a hoisting dynamic parameter set; the lifting dynamic parameter set comprises pressure distribution data of each lifting point, lifting appliance attitude angle data and load space position data; based on the hoisting dynamic parameter set, force system dynamic balance analysis is executed, and the force system unbalance degree of the crane is obtained through analysis; and when the force system unbalance degree of the crane is larger than a set threshold value, an unbalance active correction mechanism is triggered, and unbalance correction is conducted on the crane through adjustment of the electro-hydraulic proportional valve. And the safety and the efficiency of hoisting operation can be obviously improved. The automatic unbalance correction mechanism not only reduces the accident risk, but also improves the operation flexibility and response speed, and provides powerful technical support for modern hoisting operation.

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.

The invention discloses a condensation-free efficient heat exchange control method and system for a full-premixing water heater, and the method comprises the steps: collecting the multi-source information, such as air inlet temperature, humidity, gas flow, flue gas oxygen concentration and wall temperature, in real time, calculating a predicted dew point based on a dynamic dew point prediction model, and setting a dynamic safety boundary; the condensation risk is judged by comparing the wall temperature with the safety boundary, and active intervention is carried out in a staged cooperation mode that fuel gas and air volume are continuously adjusted firstly and then a partial combustion zone sectioning valve is rapidly turned off; the system comprises a main controller, a mesh-shaped infrared radiation burner, a sectional valve assembly, a gas proportional valve, a frequency conversion fan and related sensors. According to the invention, the system runs close to the condensation boundary through intelligent control, and the advantage of high operation heat efficiency is realized on the premise of ensuring high reliability.

An apparatus for operating a load-controlled hydraulic supply of an agricultural tractor includes a hydraulic pump which is adjustable with respect to the displacement volume for supplying pressurized hydraulic fluid, a proportional valve which is electrically actuatable, a primary hydraulic consumer to carry out a superordinate hydraulic function and to be directly connected to a conveying outlet of the hydraulic pump, a secondary hydraulic consumer to carry out a subordinate hydraulic function and to be connected to the conveying outlet of the hydraulic pump via the proportional valve, and a control unit configured to move the proportional valve into a closed valve position when the control unit recognizes that at least one of a required power of the primary and secondary hydraulic consumers exceeds the conveying capacity of the hydraulic pump and the subordinate hydraulic function of the secondary hydraulic consumer is inactive.

The invention discloses a miniature proportional valve control method based on active-disturbance-rejection control, and relates to the technical field of miniature proportional valve control, and the method comprises the steps that a target flow set value is received and is used as a control signal to be sent to a control unit, and the control unit comprises a tracking differentiator, an expansion state observer and a nonlinear feedback controller; the tracking differentiator processes the target flow set value to obtain a differential input signal; the expansion state observer receives the differential input signal and the actual flow feedback signal, and estimates the total disturbance of the system in real time to obtain a disturbance estimation value; the non-linear feedback controller combines the differential input signal and the disturbance estimation value to generate a compensation current signal; the compensation current signal is used as a control parameter of the micro proportional valve, and the position of the valve element is accurately adjusted. An active disturbance rejection control algorithm is adopted, the control performance and disturbance rejection are improved, accurate flow control of the micro proportional valve is achieved, and the micro proportional valve is more suitable for industrial application with high requirements.

The invention provides a hydrogen supply control method of a fuel cell system, a controller, a system and a medium, and relates to the technical field of fuel cells. The method comprises the steps that in response to a starting instruction, the opening degree proportion of a first proportional valve is controlled to be adjusted to K11 from K10 through a first PID control parameter, K10 is the opening degree proportion of the first proportional valve which does not allow hydrogen to pass at all, and K11 is the initial opening degree proportion of the first proportional valve at the current environment temperature; obtaining a current actual pile entering pressure value and a hydrogen pile entering pressure set value of the electric pile; the second PID control parameter is used for controlling the opening proportion of the first proportional valve to be adjusted till the deviation between the actual reactor entering pressure value and the hydrogen reactor entering pressure set value is within the allowable error range, and the proportionality coefficient of the first PID control parameter is larger than that of the second PID control parameter. According to the method, the stability of hydrogen pressure is improved, so that the stability and the service life of the fuel cell system are improved.

The invention discloses a UPA pressure automatic compensation system and method for mask substrate polishing. The UPA pressure automatic compensation system comprises a pressure execution module, a distributed sensing feedback network and an intelligent control unit. Wherein the pressure execution module is used for directly polishing a mask base plate and comprises a force application shaft, a polishing head, an air source, a UPA air bag and an electric proportional valve, the distributed sensing feedback network comprises an air path pressure sensor and a tail end contact pressure sensor, and the intelligent control unit receives a collection signal of the distributed sensing feedback network and sends the collection signal to the polishing head. On the basis of a current process formula and process parameter coupling model, a data fusion algorithm, a feed-forward compensation algorithm and a fuzzy PID algorithm are operated to obtain a feed-forward compensation amount and a fuzzy PID output amount, the feed-forward compensation amount and the fuzzy PID output amount are superposed, a total control voltage is generated and output to an electric proportional valve, and then the input air pressure of a UPA air bag is adjusted. Therefore, closed-loop control over the polishing pressure of the mask substrate is achieved. Through multi-sensor data fusion, fuzzy PID self-adaptive control and intelligent feed-forward compensation based on a process parameter coupling model, real-time, accurate and constant control of the polishing pressure is realized, so that the surface precision and yield of the mask substrate are improved.

The invention belongs to the technical field of cigarette production, and particularly relates to a dynamic control system and method for sliver removal of a cigarette making machine, and the system comprises a sliver removal amount detection mechanism which detects the sliver content in discharged materials in real time; the feedback adjusting mechanism comprises an electric proportional valve and an opening degree adjusting mechanism which are respectively used for adjusting the air pressure, the air volume and the opening degree of the air inlet; and the controller is in communication connection with the detecting mechanism and the adjusting mechanism, adjusts the winnowing parameters according to the sliver content signal, communicates with the MES system and realizes data uploading and process parameter receiving. The system realizes dynamic closed-loop regulation of air pressure and air volume, reduces manual intervention, and improves control precision and response speed.

The utility model belongs to the technical field of glass fiber wire drawing machines, and particularly relates to a rear-end disc type wire drawing machine head capable of automatically adjusting and avoiding a wire drawing resonance area on line. The device comprises a machine head main shaft, a bearing seat, a cylinder body, a piston, a front seat, a rear seat, a barrel replacing body and a vibration reduction component, when the machine head operates, the bearing seat, the cylinder body, the piston, the front seat, the rear seat, the barrel replacing body and the vibration reduction component form an online rigid adjusting mechanism for the soft support of the machine head. The vibration of the machine head can be detected in real time through the vibration sensor and fed back to the PLC for control, the gas flow and / or the gas pressure are / is adjusted through the proportional valve PID, online real-time data collection and exchange are achieved, dynamic closed-loop control over the machine head rigidity adjusting mechanism on the bearing seat is achieved, and the vibration of the machine head is controlled within an acceptable range all the time.

The invention relates to a new energy extended-range automobile thermal management system and a control method, and belongs to the field of automobile air conditioners. The system comprises a refrigerant loop and a cooling liquid loop, and heat management functions of a passenger compartment, a battery, an electric drive and an engine are achieved through multi-loop collaborative design. The refrigerant loop comprises first to fifth refrigerant loops, a core component is a compressor, the flow direction of a refrigerant is controlled through an electromagnetic valve and a one-way valve, and passenger compartment cooling, battery cooling and waste heat recovery are achieved. The cooling liquid loop works cooperatively with a water pump through a three-way proportional valve, and electric heat dissipation, engine heat dissipation and battery heating are achieved. Through the high coupling design of the refrigerant loop and the cooling liquid loop and the multi-target cooperative control strategy, the comprehensive efficiency and applicability of thermal management are remarkably improved, the electric energy consumption is reduced, the endurance mileage of the vehicle in a pure electric mode is prolonged, and the reliability and maintainability of the system are enhanced.

A proportional valve includes a casing and a valve trim. The casing has at least one fluid inlet, a fluid outlet, at least one first connection passageway, at least one second connection passageway and an accommodating space. The first connection passageway is connected with the fluid inlet. The second connection passageway is connected with the fluid outlet. The valve trim is located in the accommodating space, including a flow splitter an adjusting rotor. The flow splitter has at least one third connection passageway and at least one fourth connection passageway. The third connection passageway is connected with the first connection passageway. The fourth connection passageway is connected with the second connection passageway. The adjusting rotor has a channel and at least one blocking portion. The adjusting rotor is rotatably disposed on the flow splitter so that the blocking portion blocks a part of the third connection passageway.

The invention discloses a self-adaptive control method for a proportional valve, and particularly relates to the technical field of hydraulic control, and the method comprises the steps: recognizing behavior deviations such as response imbalance, inertia abnormality or environment sudden change by obtaining multi-dimensional operation data in the hydraulic control in real time, and judging whether to enter an evaluation process or not; after entering the process, extracting control behavior characteristics, calculating a dynamic structure compression degree and a control energy spectrum dispersion rate, inputting the dynamic structure compression degree and the control energy spectrum dispersion rate into a pre-training machine learning model, and outputting a control effectiveness score; respectively triggering parameter reconstruction, strategy replacement or control logic correction according to a grading threshold interval in which the score is located, so as to realize intelligent and self-adaptive regulation and control and performance maintenance of a proportional valve control strategy; preposed perception and risk judgment of control behaviors of the proportional valve are achieved, structured indexes are constructed to evaluate control adaptability, a fuzzy inference device is combined to output scores, parameter reconstruction, strategy replacement or logic correction are triggered according to risk levels, and intelligentization, self-adaptive regulation and control and stable maintenance of a control strategy are achieved.

The utility model belongs to the technical field of glass fiber wire drawing machines, and particularly relates to a wire drawing machine head with an inward taper, which can automatically adjust and avoid a wire drawing resonance area on line. The device comprises a machine head main shaft, a bearing seat, a front seat, a rear seat, a front taper sleeve, a rear taper sleeve and a vibration reduction component, the front taper sleeve and the rear taper sleeve are both arranged on the bearing seat, and the conical surfaces are matched with the front conical part and the rear conical part respectively; the front seat is arranged on the bearing seat, and a front sealing cavity is formed between the front seat and the front taper sleeve; the rear seat is arranged on the bearing seat, and a rear sealing cavity is formed between the rear seat and the rear taper sleeve; the front and rear sealing cavities are respectively provided with front and rear inflation ports. PLC control can be fed back through machine head vibration real-time detection, proportional valve PID adjustment is adopted, online real-time data collection and exchange are achieved, a soft supporting vibration reduction device on a bearing seat is controlled, and vibration is controlled within an acceptable range.

The invention relates to the technical field of semiconductor manufacturing, and discloses an integrated vacuum system test method of a mechanical arm and a vacuum test platform. A vacuum test platform which is provided with a two-stage vacuum system and a multi-channel proportional valve and is designed in a modular architecture mode is adopted for sequentially carrying out pre-installation calibration, vacuum environment simulation, positioning precision testing, vacuum adaptability testing and durability testing. The vacuum test platform is provided with a fine tuning clamping groove which is matched with the altimeter to ensure that the mounting position of the mechanical arm to be tested is accurate and the actual condition of the photoetching machine is reetched; a plurality of general standardized interfaces are also arranged, so that quick switching of to-be-tested mechanical arms of different models is realized; in the analysis stage, the three test results are analyzed, whether the performance of the mechanical arm to be tested reaches the standard or not is evaluated, the capability of integrally testing indexes such as positioning precision, vacuum adaptability and durability is achieved, external pre-debugging of the mechanical arm under the working environment of the simulated photoetching machine is achieved, and the debugging efficiency and precision are improved.

According to the novel ultrahigh pressure proportional valve and the hydraulic control system, a piston cavity is formed in a valve body, a low-pressure piston block is arranged in the piston cavity, and a high-pressure cavity is formed in one side of the low-pressure piston block; the cavity body section of the high-pressure cavity is smaller than that of the piston cavity; a high-pressure piston block is arranged in the high-pressure cavity and is linked with the low-pressure piston block; the high-pressure cavity is connected with the high-pressure oil port, the piston cavity is connected with the low-pressure oil port, and one or more pressure relief oil ports are formed in the high-pressure cavity or the piston cavity. When the structure is used in a hydraulic control system, oil in the high-pressure cavity can be restrained to be discharged slowly through the low-pressure piston block, and the high-pressure cylinder can be controlled to stabilize pressure in a certain high-pressure state through proportional oil discharge. According to the hydraulic system, the defects in the prior art are overcome, stable control over the high-pressure oil cylinder can be achieved, during high-pressure unloading, the high pressure cannot be directly reduced to the lowest state, and linear unloading and pressure stabilization can be achieved.

The utility model belongs to the technical field of glass fiber drawing machines, and particularly relates to a drawing machine head with an outward taper, which can automatically adjust and avoid a drawing resonance area on line. The device comprises a machine head main shaft, a bearing seat, a front taper sleeve, a rear taper sleeve, a barrel replacing body, a sealing cavity and an inflation inlet, the taper of the front taper sleeve and the taper of the rear taper sleeve face outwards, and the conical surfaces of the front taper sleeve and the rear taper sleeve are opposite. When the machine head of the wire drawing machine operates, real-time detection and feedback of PLC control can be realized through the machine head vibration sensor, and PID adjustment of the proportional valve is adopted, so that online real-time data acquisition and exchange are realized, a soft support vibration reduction device on a bearing seat is controlled, vibration of the machine head is automatically controlled within a suitable range, and online closed-loop real-time adjustment of rigidity of the machine head is realized.

The invention relates to the technical field of proportional valves, and discloses a stepless speed regulation proportional valve with displacement detection, which comprises a valve body, a proportional controller is arranged at the bottom of one side of the valve body, a proportional cavity is arranged in the valve body, the size of the bottom of the proportional cavity is larger than that of the top, a conical surface is arranged at the joint, and an inlet cavity is arranged at the top of one side of the valve body. An outlet cavity is formed in the bottom end of the valve body, a valve rod is arranged in the valve body, a valve element is fixedly arranged at the bottom of the valve rod, a permanent magnet is arranged at the top of the valve rod, a shell is arranged at the top end of the valve body, and a displacement detector is arranged in the shell. When the valve rod drives the valve element to move, the displacement detector can move synchronously under the action of the supporting spring, the position, the movement speed and the movement direction of the valve element are detected, and the accuracy of the proportional valve is guaranteed; and the positions of the connecting pipe and the pipeline can be preliminarily positioned through the arranged positioning clamp.

The utility model provides a proportional valve which comprises a fixing cover, a valve chamber and a valve rod assembly. The fixing cover is provided with a containing cavity. One end of the valve chamber is arranged in the containing cavity, a sealing piece is arranged between the valve chamber and the fixing cover, the valve chamber is provided with a quantitative cavity, one end of the quantitative cavity is provided with a feeding port for materials to enter, and the other end of the valve chamber is provided with a sealing piece. The valve rod assembly comprises a valve element, an elastic piece and a valve rod piece. The valve element is elastically installed in the quantitative cavity through the elastic piece so as to axially move to abut against the sealing piece or block the feeding port. One end of the valve rod piece penetrates through the sealing piece and extends into the valve element, the valve rod piece is hollow, and a feeding gap for feeding is formed between the valve rod piece and the valve element; the valve rod piece is pressed to push the valve element to be separated from the sealing piece, so that a feeding area for materials to enter the valve element is formed between the valve element and the sealing piece, and one end of the valve element blocks the feeding opening; materials in the quantitative cavity pass through the feeding area, then enter the valve rod piece through the feeding gap and are discharged. The utility model further provides an aerosol.

The invention discloses an electrical control device for high-pressure protection in a hydraulic control system, which relates to the technical field of hydraulic control and comprises a high-pressure detection module for monitoring pressure data of the hydraulic system in real time and transmitting the pressure data to a control processing core through an analog quantity input module. Two-channel independent control logic is adopted through the redundancy protection unit, even if a single loop breaks down, the other loop can still independently execute a safety instruction, the risk of single-point failure is eradicated, meanwhile, the intelligent control unit achieves advanced and accurate pressure adjustment and trend suppression through a high-frequency-response electro-hydraulic servo valve and a proportional valve and depending on bus communication, and the safety performance of the system is improved. The high-voltage risk is eliminated in the bud, the leap from passive response to active protection is achieved, high system integration and intelligent management are achieved through the intelligent valve terminal, remote monitoring and diagnosis are supported while wiring is simplified, and maintainability is enhanced.

The invention relates to a high-precision micro-pipetting device and a control method thereof, and the pipetting device, the high-precision micro-pipetting device comprises a control module, a positive pressure system, a negative pressure system, a three-way solenoid valve and a pipetting head, the control module controls the switching of the three-way solenoid valve to enable a micro-control solenoid valve to be communicated with the positive pressure system or the negative pressure system, and the control module controls the opening time of the micro-control solenoid valve; a proportional valve, a pressure sensor and a flow sensor are arranged between the three-way electromagnetic valve and the micro-control electromagnetic valve, the proportional valve is used for adjusting the pressure and the flow of a gas circuit, and the control module conducts PID control on the proportional valve according to measurement data of the pressure sensor and the flow sensor. The positive / negative pressure value and the gas flow rate of the gas circuit are adjusted through the proportional valve, so that the positive / negative pressure at the liquid suction head can be changed, the suction and discharge of samples with different viscosities can be realized, the switching time of the liquid suction head is controlled through the micro-control electromagnetic valve, and the sample amount of each time of pipetting can be accurately controlled.

A multi-way valve, related to the technical field of control valves, is used to solve the problem of large occupied space, complicated control, and high cost, because of the use of two driving devices for controlling a three-way proportional valve and a two-way proportional valve, where a driving device is connected to a first valve core in a transmission way, and the first valve core is provided with a first matching structure, and a second valve core is provided with a second matching structure that matches the first matching structure. In the first matching state, the first valve core rotates alone and the second valve core remains stationary; in the second matching state, the first valve core rotates to drive the second valve core to rotate synchronously.

The utility model belongs to the technical field of proportional valves, and particularly relates to an electromagnetic proportional valve which comprises a shell, a static iron, a coil, a spring, a movable iron, a valve element and a stabilizing piece, an installation cavity is formed in the shell, the static iron is installed in the installation cavity and connected with the shell, the coil is wound on the peripheral face of the shell, and the movable iron is arranged in the installation cavity and connected with the valve element. The valve element is connected with the end, away from the static iron, of the movable iron, the spring is connected between the movable iron and the static iron, the shell is further provided with a liquid cavity, an inflow channel and an outflow channel, the liquid cavity is formed in the side, away from the static iron, of the valve element, the end, away from the movable iron, of the valve element extends into the liquid cavity, and the inflow channel and the outflow channel are both communicated with the liquid cavity. The stabilizing piece is arranged in the mounting cavity, the moving iron is connected with the stabilizing piece, and the stabilizing piece can limit the moving iron in the radial direction of the moving iron. Radial shaking of the moving iron in the mounting cavity is avoided, stability of the moving iron is improved, collision abrasion between the moving iron and the cavity wall of the mounting cavity is prevented, operation stability of the electromagnetic proportional valve is improved, and the service life of the electromagnetic proportional valve is prolonged.

The invention discloses a combustor safety control system for a negative pressure furnace, relates to the technical field of combustion control of negative pressure furnaces, and aims to solve the technical problems that single closed-loop control response of an existing negative pressure furnace combustor is lagged, and the system stability is poor. According to the system, a double-closed-loop control framework of cooperative work of an inner-layer combustion stability closed loop and an outer-layer negative pressure closed loop is constructed, flame characteristic parameters and the gas / air proportion serve as core control objects of the inner-layer closed loop, the opening degree of a gas proportional valve and the rotating speed of a draught fan are adjusted in real time through a PID algorithm, and the combustion state is kept stable; the outer-layer closed loop dynamically adjusts the opening degree of the hearth baffle valve based on the inner-layer adjusting result so as to maintain the negative pressure within a preset range; when any closed loop is abnormal, the system automatically triggers a cross-closed-loop compensation mechanism, and the other closed loop optimizes self-adjusting parameters in real time to realize dynamic compensation. Through double-closed-loop cooperation and abnormal compensation design, the control response speed and operation safety of the negative pressure furnace combustor are greatly improved, the problem of response lag of single closed-loop control is effectively solved, and the method is suitable for safety control of various industrial negative pressure furnace combustion systems.

The invention discloses a vehicle thermal management system and a control method, and relates to the technical field of vehicle thermal management, the system comprises a refrigerant circulation loop, a battery circulation loop, a warm air circulation loop and an engine circulation loop; the refrigerant circulation loop is coupled with the battery circulation loop through a battery cooler; the battery circulation loop and the warm air circulation loop are coupled through a first three-way proportional valve and a first three-way pipe joint; the warm air circulation loop and the engine circulation loop are coupled through a second three-way proportional valve and a third three-way pipe connector. According to the scheme, heat management components are reduced, the cost is greatly reduced, direct coupling of the engine, the warm air high-temperature loop and the battery low-temperature loop is achieved, meanwhile, separate and independent control over the water temperature of the warm air core and the water temperature of the battery is achieved, and the risk of thermal runaway caused by overheating of the battery is effectively avoided.