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78results about How to "Precise closed-loop control" patented technology
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Multiple channel ballast and networkable topology and system including power line carrier applications
InactiveUS7009348B2Efficient qualityExtend lamp lifeAnalogue/digital conversionElectric light circuit arrangementLoop controlElectric power system
Control systems and methods for independent control of power systems, particularly lighting network branches, and separate control of individual branch components. Multi-branch systems comprise independently controllable branches that inter-communicate via PLC communications. In each branch, components such as ballasts, local control units, sensors, actuators, and repeaters, may exchange commands and queries independently of a branch remote control unit (BRCU). Alternatively, a BRCU may manage or arbitrate communications, or interact with other BRCUs, other control units and external management systems. Ballasts include a multi-channel ballast that enables close-loop control of individual fixtures, or of individual dimmable or non-dimmable lamps within a fixture. The close-loop control is facilitated by sampling circuits / sensors co-located with each controlled fixture or lamp. All controllers are preferably implemented using an integrated digital controller. The PLC communication is preferably carried out by a direct spread spectrum method that eliminates side lobes from a cross-correlation function, using an anti-collision protocol.
Owner:S T L ENERGY SOLUTIONS & TECH
Electric control method and electric control device for adjustment of hydraulic suspension position of tractor
InactiveCN104541636APrecise closed-loop controlReal-time monitoring of position control parametersAgricultural machinesAdjusting devicesElectro hydraulicEngineering
The invention discloses an electric control method and an electric control device for adjustment of a hydraulic suspension position of a tractor. The electric control method and the electric control device are applied to a hydraulic suspension system of the tractor. The device comprises an electro-hydraulic proportional directional valve, a controller, an angle sensor, a display, a control panel and the like. The display, the control panel and the controller are mounted in a cab of the tractor or a right wheel fender, and the controller is respectively connected with the control panel, the display, the angle sensor and the electro-hydraulic proportional directional valve through cables. The angle sensor is respectively connected onto a lifter shell of the tractor and a rotating shaft of an external lifting arm of the tractor to detect relative positions of agricultural implements to the tractor. The electro-hydraulic proportional directional valve is capable of controlling the hydraulic suspension system to lift an oil cylinder according to signals of the controller, and accordingly operation positions of the agricultural implements can be adjusted.
Owner:JIANGSU UNIV +1
Multiple channel ballast and networkable topology and system including power line carrier applications
InactiveUS20060208661A1Efficient qualityExtend lamp lifeAnalogue/digital conversionElectric signal transmission systemsLoop controlElectric power system
Owner:S T L ENERGY SOLUTIONS & TECH
Novel air distribution system with variable lift
ActiveCN101446218AReduce frictionReduce pumping lossValve arrangementsInternal combustion piston enginesDistribution systemEngineering
The invention provides a novel air distribution system with variable lift, which is applied to the field of the internal-combustion engine of the motor vehicle. The novel air distribution system with variable lift comprises a hydraulic tappet (1), an air valve (2) and a rocking arm (3), and further comprises a transmission gear (7), an adjusting rod (9) and a stepping motor (10), wherein, a cam shaft (6) is arranged between the rocking arm (3) and the adjusting rod (9), the cam of the cam shaft is in contact with the adjusting rod (9), the adjusting rod (9) is connected with the transmission gear (7), and the transmission gear (7) is meshed with the stepping motor (10). By adopting the technical scheme, the invention has the advantages that the purpose that the air valve is changed along with the demands of the operating conditions is achieved, and the performance of the engine is optimized to the utmost extent; the structure is simple and compact, and the design is reasonable; and the modification of the engine applying the mechanism is small. Furthermore, the invention is suitable for upgrading for the production products.
Owner:CHERY AUTOMOBILE CO LTD
Fully automatic transplanting combined machine
PendingCN110278729AGood plastic effectNot easy claySpadesTilling equipmentsControl systemAgricultural engineering
The invention provides a fully automatic transplanting combined machine. The machine includes traction equipment, operation equipment and a control system. The operation equipment is installed on a main machine frame and towed behind the traction equipment. The machine is characterized in that the operation equipment includes a rotary tillage ditching system, a micro soil preparation narrow-ditch formation system, a transplanting system and a soil covering and pressing system. The transplanting system includes more than one transplanting units. The combined machine can perform ordered rotary tillage stubble cleaning on an untilled land, bed surface leveling, ditch formation, narrow slit formation, transplanting, soil covering and compacting at a time, the soil condition required by high-speed transplanting of blanket seedlings of crops such as rapeseed is met, soil is not easily attached onto working parts for tillage and soil preparation, the transplanting quality can still be guaranteed under the condition of high-speed transplanting, structure configuration is reasonable, production, manufacturing, management and maintenance are easy, and the machine is suitable for application and popularization.
Owner:NANJING AGRI MECHANIZATION INST MIN OF AGRI
Internally-arranged angle sensor all-in-one ultrasonic motor servo control system
ActiveCN103414376APrecise closed-loop controlAffect speedPiezoelectric/electrostriction/magnetostriction machinesControl signalControl system
The invention discloses an internally-arranged angle sensor all-in-one ultrasonic motor servo control system and relates to servo control over ultrasonic motors. The internally-arranged angle sensor all-in-one ultrasonic motor servo control system comprises a command module, a compensation module, a digital processing module, a drive panel and an all-in-one actuating mechanism. The command module sends out commands to the compensation module, and the compensation module converts the commands into frequency control signals and transmits the frequency control signals to the digital processing module; the digital processing module processes the frequency control signals into square signals and transmits the square signals to the drive panel, the drive panel amplifies the square signals and then inputs the square signals to the all-in-one actuating mechanism, the all-in-one actuating mechanism is a hollow ultrasonic motor with an internally-arranged angle sensor, the angle sensor feeds back speed and position information, the speed and position information reaches the compensation module after passing through the drive panel and the digital processing module, through comparison, compensation and conversion, newly-generated frequency control signals are transmitted to the drive panel, and therefore closed-loop control is achieved. The internally-arranged angle sensor all-in-one ultrasonic motor servo control system has high reliability, high precision and good environmental suitability, and is especially suitable for being used as shaft end servo control systems of platforms with multi-degrees of freedom.
Owner:BEIJING PULIMEN ELECTRO MECHANICAL HIGH TECHN CO
Device and method for detecting pressure regulation performance of gas pressure regulator
InactiveCN103439125ARealize closed-loop controlPrecise closed-loop controlStructural/machines measurementLoop controlSolenoid valve
The invention discloses a device and method for detecting the pressure regulation performance of a gas pressure regulator. The detecting device comprises a gas channel part and a control part. The gas channel part comprises a gas source, a ball valve, a filter, a reducing valve, a high pressure solenoid valve, a proportional pressure regulating valve, the measured pressure regulator, a low pressure solenoid valve, a flow control valve and a flow sensor. The control part is composed of an industrial control computer, a driver board, a display and a data acquisition card. The flow control valve, the flow sensor and a software PID control algorithm achieve closed-loop control over the flow, and provide accurate flow regulation for an outlet of the measured pressure regulator. The detecting method comprises the following steps: starting a test, initializing devices and variables, measuring closing pressure and outlet pressure, testing pressure regulation static characteristics, judging whether the measured pressure regulator is qualified or not, and ending the test. The device and method achieve closed-loop control over the flow under the low pressure, ensure that inlet pressure of the gas pressure regulator is kept constant and the flow of the outlet is controlled accurately, measure the closing pressure, the outlet pressure, the pressure regulation static characteristics and pressure return difference of the pressure regulator rapidly and accurately, and have the advantages of being reliable in performance, high in degree of automation in the detection process, high in precision and the like.
Owner:安徽中科智能高技术有限责任公司
Full-closed loop electro-hydraulic servo plate bending machine
The invention relates to a full-closed loop electro-hydraulic servo plate bending machine which comprises a frame, master cylinders, a vertical plate, a mechanical deflection compensating workbench, a slide block and a numerical control system, wherein the master cylinders are located on the two sides above the frame; the vertical plate is located on the lower part of the frame; the mechanical deflection compensating workbench is located on a lateral side of the upper part of the vertical plate; the slide block is located above the vertical plate; the numerical control system is located on the frame; the full-closed loop electro-hydraulic servo plate bending machine is characterized by further comprising a hydraulic system and a servo motor which are connected with the numerical control system, and an oil pump which is connected with the servo motor; the hydraulic system is connected with the oil pump and the cylinder; a cylinder piston rod of the cylinder is connected with the slide block; a pressure value is closed-loop fed back to a servo driver by a machine tool; the system pressure is controlled by adjusting the rotating speed of the oil pump motor by the servo driver, so that the full-closed loop control is realized. The pressure of the hydraulic system is accurately closed-loop controlled by a servo system provided by the invention, so that the stability of the hydraulic pressure is ensured, the flow of the whole hydraulic system is subjected to accurate closed-loop control, and the overflow quantity is reduced.
Owner:SHANGHAI ACL CNC MACHINE TOOL
Device and method for achieving automatic grabbing and accurate attaching of aircraft thermal insulation piece
ActiveCN105252251AAccurate fitReduce the cumulative error of fittingGripping headsMetal working apparatusThermal insulationComputer module
The invention relates to a device and method for achieving automatic grabbing and accurate attaching of an aircraft thermal insulation piece. The device comprises an outer frame module, a main shaft module, a normal leveling module, a vision alignment module, a pressure detection module and a suction cup set module. By means of the vision alignment module, the center of the thermal insulation piece and the center of the area where the thermal insulation piece is to be attached can be accurately found, the thermal insulation piece can be accurately attached to a machine body, and accuracy of all attached positions of the thermal insulation piece is ensured. By means of the normal leveling module, the axis of a motor, the center of a corresponding suction cup and the curved surface normal of the thermal insulation piece accurately coincide, and therefore tension and pressure can coincide with the normal of the thermal insulation piece all the time, and it is ensured that the force direction is perpendicular to the outer surface of the thermal insulation piece all the time when attachment and adhesion detection are conducted; the force, in the axial direction, of the motor is detected in real time through the pressure detection module, and therefore accurate and closed-loop control over loading of the motor is achieved; and by means of the suction cup set module, flexible design and adjustment of the diameter, the number and positions of suction cups are achieved according to requirements, and thermal insulation pieces of different sizes and irregular shapes are grabbed.
Owner:NORTHWESTERN POLYTECHNICAL UNIV
Double-mode planet series-parallel connecting system and control system thereof
ActiveCN104648116APrecise closed-loop controlSolve problems that cannot be precisely controlledHybrid vehiclesGas pressure propulsion mountingControl systemClosed loop
The invention relates to the field of a hybrid power vehicle, in particular to a double-mode planet series-parallel connecting system and a control system thereof. The double-mode planet series-parallel connecting system is characterized in that a torque sensor is connected between an output shaft of an engine and a planet row system in series, the torque sensor is connected with a whole vehicle controller, accurate torque Eng_Trq actually output by the engine can be obtained through the feedback of the torque sensor, and closed loop PI correction on the torque control of the engine is realized, i.e. (1) the situation that the torque output of the engine is enlarged when the torque is smaller than a target torque is realized; (2) the situation that when an actual torque is greater than the target torque, the engine stops outputting a target command, and a load of the engine is in reverse drawing is realized. When the double-mode planet series-parallel connecting system disclosed by the invention is used, analog quantity signals can be collected by the torque sensor in real time, a current actual torque value of the engine can be calculated by the whole vehicle controller according to the obtained analog quantity signals, accurate closed loop control on the engine can be realized through control strategy calculation, and thus the problem that working points of the engine of the planet row system cannot be accurately controlled is solved.
Owner:ZHENGZHOU YUTONG BUS CO LTD
Stacker-reclaimer pitching hydraulic system, close loop control system and control method
ActiveCN106837946AReduce energy consumptionImprove work efficiencyServomotor componentsServomotorsReclaimerCheck valve
The invention discloses a stacker-reclaimer pitching hydraulic system, a close loop control system and a control method. The system comprises a main loop for controlling the stacker-reclaimer suspension arm pitching mechanism to move, a hydraulic control check valve control loop for providing inverse opening pressure to a hydraulic control check valve, and a manual control loop for supplying power to the system when the system is power-off or has fault. According to the stacker-reclaimer pitching hydraulic system, the close loop control system and the control method, the design requirement is achieved through controlling the speed of the pitching hydraulic cylinder and the vertical displacement of the suspension arm to make sure that the stacker-reclaimer can operate highly efficiently, stably and reliably.
Owner:DALIAN HUARUI HEAVY IND GRP CO LTD
In-use vehicle SCR post-treatment control method and system
InactiveCN111622830APrecise closed-loop controlAutomatic adjustment of injection volumeInternal combustion piston enginesExhaust apparatusExhaust gasEngine displacement
Owner:WUXI WEIFU LIDA CATALYTIC CONVERTER
Control system for urea pump
InactiveCN110953046AOptimize layoutLow costInternal combustion piston enginesExhaust apparatusControl systemElectric machinery
The invention provides a control system for a urea pump. The control system for the urea pump comprises an input interface module, an output interface module, an SCR control module and a urea pump control module, wherein the input interface module is used for transferring an external input signal to the SCR control module; the output interface module is used for sending the external input signal output by the SCR control module to a related executer, a CAN communication line and a diagnostic apparatus; the SCR control module is mainly used for carrying out urea pump drive, urea injection amount calculation and urea system heating drive according to the external input signal and a feedback signal of the urea pump, and sending the external input signal to the related executer, the CAN communication line and the diagnostic apparatus through the output interface module; and the urea pump control module is mainly used for executing a pump motor drive signal of the SCR control module, a drive signal of a pump heater and a drive signal of a pumpback valve, and controlling a urea pump motor, the pump heater and the pumpback valve. The control system for the urea pump integrates an SCR control function with a urea pump control function.
Owner:WUXI WEIFU LIDA CATALYTIC CONVERTER
Closing unit of a shaping machine
Owner:ENGEL AUSTRIA
Baking method and device
ActiveCN107752794AEffective closed-loop controlPrecise closed-loop controlCharacter and pattern recognitionRoasters/grillsProcess engineeringComputer science
The invention discloses a baking method and device. The baking method comprises the steps of obtaining a temperature distribution picture used for identifying the temperature of the interior of a baking utensil in which content is put; determining a baking strategy used for baking the content through a strategy identifying model, wherein the strategy identifying model is obtained by using multiplesets of data to conduct machine learning and training, and each set of data of the multiple sets of data comprises the corresponding temperature distribution picture and the corresponding baking strategy for baking the content corresponding to the temperature distribution picture; baking the content according to the determined baking strategy. The technical problem in the related art that bakingequipment is not intelligent enough is solved.
Owner:GREE ELECTRIC APPLIANCES INC
Double-hemispheric capsule robot attitude detection method based on magnetic vector error calibration image
ActiveCN110327011AImprove utilization efficiencyAvoid interferenceSurgeryEndoscopesDistribution characteristicRotation matrix
The invention discloses a double-hemispheric capsule robot attitude detection method based on a magnetic vector error calibration image and belongs to the technical field of automation engineering. The method uses the error distribution characteristic of a spatial universal rotation magnetic vector, firstly, the least azimuth error direction of the magnetic vector is determined as an initial imagecalibration position of the attitude of a double-hemispheric capsule robot, image information before and after attitude adjustment is acquired by a camera, recognition and matching of feature pointsof the image are performed, the relative attitude change before and after attitude adjustment is obtained by combination of epipolar geometry and a rotation matrix, and the actual attitude of the double-hemispheric capsule robot is effectively estimated. The method can estimate the attitude of the double-hemispheric capsule robot in wide gastrointestinal environments only by the camera carried bythe robot without any external hardware resources.
Owner:DALIAN UNIV OF TECH
Gas power generation set
InactiveCN104989517AFlexible controlFlexible layoutInternal combustion piston enginesFuel supply apparatusAir filterClosed loop
The invention discloses a gas power generation set which comprises a power generator body. The power generator body comprises an energy supply system, an energy transduction system and a control unit. The energy supply system comprises a gas supply unit, a gas jet valve and a mixer, wherein the gas jet valve and the mixer are connected with the gas supply unit. The energy transduction system comprises an air filter and a plurality of sensors connected with the air filter. The control unit is composed of an electronic control unit (ECU). The sensors comprise the air inlet temperature pressure sensor, the water temperature sensor, the crankshaft position sensor, the oxygen sensor and the phase position sensor. The air filter comprises an air inlet pipeline. The mixer is arranged on the air inlet pipeline. Control is flexible, and single-point jet control or multi-point jet control can be conducted according to application conditions. The wide-range oxygen sensor is adopted, so that accurate closed-loop control over the air-fuel ratio is achieved in the whole process; electronic throttle valve control is achieved; boost pressure closed-loop control is achieved; accurate control over engine power and a torque curve is achieved; the air-fuel ratio control precision is high, and air consumption is low; parts of a system are simply and flexibly distributed; the system is stable and reliable, and the price is low.
Owner:DONGGUAN SHENGDONG NEW ENERGY TECH CO LTD
Brushless doubly-fed motor control system, feed forward control method and parameter identification method
ActiveCN108322117ALow costEliminate couplingElectronic commutation motor controlVector control systemsProportional controlCoupling
The invention discloses a brushless doubly-fed motor control system, a feed forward control method and a parameter identification method. The control system comprises a d-axis control structure for outputting a d-axis component of a voltage command value and a q-axis control structure for outputting a q-axis component of the voltage command value. The d-axis control structure comprises a first PIcontroller, a first proportional controller, a second proportional controller, a first differential controller, a first superimposer and a second superimposer. The first proportional controller, the second proportional controller and the first differential controller are used for generating a first d-axis intermediate component, a second d-axis intermediate component and a third d-axis intermediate component respectively. The first PI controller is used for outputting a d-axis component of a voltage initial reference value; and the second superimposer is used for carrying out superposition processing on the d-axis feed forward quantity of the voltage reference value and the d-axis component of the voltage initial reference value to output a voltage command value. The control system eliminates a coupling term between the current and voltage of a control winding, and realizes accurate closed-loop control.
Owner:HUAZHONG UNIV OF SCI & TECH
Dual-mode planetary hybrid system and its control system
ActiveCN104648116BPrecise closed-loop controlSolve problems that cannot be precisely controlledHybrid vehiclesGas pressure propulsion mountingDual modeControl system
Owner:ZHENGZHOU YUTONG BUS CO LTD
Auxiliary heating furnace door system for heat treatment equipment
InactiveCN109509712AFast temperature recoveryEfficient SupplementSemiconductor/solid-state device manufacturingElectricityEngineering
The invention discloses an auxiliary heating furnace door system for heat treatment equipment, including a furnace door. An electric heater is arranged on the inner side of the furnace door. The electric heater is equipped with a power supply module, a temperature sensor for detecting the temperature of the furnace mouth area of heat treatment equipment, and a regulation component for regulating the heating power of the electric heater. The power supply module is connected with the electric heater through the regulation component. The temperature sensor is connected with the regulation component. The system has the advantages as follows: the structure is simple; temperature return after opening / closing of the furnace door is fast; the stability and consistency of the temperature field aregood; and the product quality is ensured, and the production efficiency is improved.
Owner:48TH RES INST OF CHINA ELECTRONICS TECH GROUP CORP
Three-dimensional (3D) printer, and closed-loop control system and control method for printer forming platform
InactiveCN111267338AReduce feverGrow fastAdditive manufacturing apparatus3D object support structuresLoop controlComputer printing
The invention belongs to the field of three-dimensional (3D) printing, and particularly relates to a 3D printer, and a closed-loop control system and control method for a printer forming platform. Thecontrol system comprises a main controller, a motor driver, a closed-loop stepping motor, a ball screw driving mechanism, the forming platform and grating rulers, wherein the ball screw driving mechanism is formed by building two ball screw straight-line modules which are mutually independent and mutually perpendicular, and realizes X-Y direction driving through a ball screw pair and a linear guideway pair; the forming platform is fixed onto a nut seat; the nut seat is connected with a lead screw nut; the closed-loop stepping motor is connected with the main controller through the motor driver; the rotational motion of the closed-loop stepping motor is transformed into the linear motion of the forming platform through the ball screw driving system; and the grating rulers are adopted as position feedback elements, are parallel to linear guideways in X and Y directions, and feedback actual displacement information of the forming platform to the main controller, so that the closed-loop compensation is realized, and the printing precision of a forming piece is improved.
Owner:NANJING UNIV OF SCI & TECH
Atomizing arrangement
InactiveUS20060060679A1Compact structurePrecise mixture formationFlow mixersExhaust apparatusHydrogenCompound (substance)
An atomization system for fuels, particularly for charging a chemical reformer for obtaining hydrogen, includes at least one metering device for metering fuel at at least one metering point into a connecting tube capable of receiving a temperature-adjusted substance stream. The connecting tube features at least one atomization point located downstream of the at least one metering point.
Owner:ROBERT BOSCH GMBH
Accurate closed-loop control scheme for fiber-optic gyroscope transit time
PendingCN112240765AImprove long-termHigh precisionSagnac effect gyrometersLoop controlFrequency spectrum
The invention relates to an accurate closed-loop control scheme for fiber-optic gyroscope transit time. The accurate closed-loop control scheme comprises on-line real-time locking of fiber-optic gyroscope transit time parameters, two-stage feedback closed-loop control and four modulation waveform combination schemes given according to different design requirements. The main working process of themethod comprises the steps that high-frequency cosine wave modulation is applied to a phase modulator, spectral analysis is conducted on detector output, online real-time monitoring of the transit time is achieved through a digital phase locking scheme, real-time accumulation and rounding filtering processing are conducted on data, and the data are output to the next stage; a preliminary adjustment result is given through frequency division of control circuits such as an FPGA or a DSP, output of the adjustable crystal oscillator is controlled according to a further difference value, and feedback control with the precision superior to the ppm magnitude is achieved. The scheme is a third key parameter closed-loop control scheme after the fiber-optic gyroscope realizes rate closed-loop and phase modulation coefficient closed-loop, and has very important significance for stabilizing the scale factor and the zero offset parameter and improving the engineering performance of the fiber-opticgyroscope.
Owner:武汉中科锐择光电科技有限公司
Energy storage bidirectional converter system for harmonic compensation and control method
ActiveCN108683190AQuality improvementExtend your lifeHarmonic reduction arrangementAc network to reduce harmonics/ripplesPower qualityCompensation effect
The invention relates to an energy storage bidirectional converter system for harmonic compensation and a control method, and belongs to the technical field of harmonics reduction. The invention solves the problem of excessive nonlinear load harmonic current by utilizing the existing energy storage bidirectional converter in the micro grid, and optimizes the power quality of the micro grid. The invention eliminates the influence of the long distance feeding line and improves the harmonic compensation effect by directly collecting the nonlinear load side harmonic information. A voltage and current model is established; the harmonic current characteristic value and the PCC point characteristic emitted by the nonlinear load are extracted by a signal measurement coding device; the communication information amount is compressed, and the harmonic information is transmitted through a narrowband wireless communication device; and a local controller receives the information of the signal measurement coding device and then decodes the information, so as to restore the real load harmonic current, thereby realizing the closed-loop proportional resonance control of the energy storage bidirectional converter, and realizing the accurate compensation of the harmonic current of any number of times. The invention has the advantages of low cost, excellent effect and simple engineering realization.
Owner:STATE GRID SHANDONG ELECTRIC POWER +2
Brushless direct-current motor position-free commutation method and system suitable for variable-speed working condition
ActiveCN111987941AEliminate commutation errorsImprove accuracyElectronic commutation motor controlPhysicsEngineering
The invention relates to a brushless direct-current motor position-free commutation method and system suitable for a variable-speed working condition. The commutation method comprises the steps: obtaining a three-phase counter electromotive force signal of a brushless direct-current motor under the variable-speed working condition; acquiring a three-phase virtual Hall signal according to the three-phase counter electromotive force signal; obtaining feedback signals, and sampling the feedback signals before and after a three-phase virtual Hall signal commutation point to obtain feedback quantities; and performing a closed-loop PI control algorithm according to the feedback quantities to control commutation of the brushless direct current motor. According to the brushless direct-current motor position-free commutation method and system, the closed-loop control of the commutation error of the brushless direct current motor is effectively realized; phase change errors caused by feedback quantity distortion under the variable speed working condition can be effectively eliminated, the accuracy of position-free commutation of the brushless direct current motor under the variable speed working condition is improved, and accurate closed-loop control over the commutation errors can be achieved during constant speed and variable speed of the brushless direct current motor.
Owner:NINGBO INST OF TECH BEIHANG UNIV +1
Porpoising dolphin propulsion mechanism based on clutch transformation
ActiveCN108482626AConducive to jumping waterReduce weightPropulsive elements of non-rotary typeBall screwCam
The invention discloses a porpoising dolphin propulsion mechanism based on clutch transformation. The porpoising dolphin propulsion mechanism based on clutch transformation comprises a frame, an internal shaft, an external shaft, a ball screw internal and external shaft clutching mechanism, an eccentric amplitude adjusting mechanism and a sine swinging mechanism, wherein the internal shaft is arranged on the frame; the eccentric amplitude adjusting mechanism is connected with the internal shaft and the external shaft; and the sine swinging mechanism is connected with the eccentric amplitude adjusting mechanism. According to the porpoising dolphin propulsion mechanism based on the clutch transformation, engaged and disengaged states between splines of the internal shaft and the external shaft are realized by using a screw at the bottom of the frame; and the two states are correspondingly an amplitude adjusting state and a sine swinging state. The amplitude is adjusted when the splines of the internal shaft and the external shaft are separated. One set of crank slide block mechanism is positioned at the right end of the frame to realize the sine swinging of a swinging rod. Accordingto the porpoising dolphin propulsion mechanism based on the clutch transformation, by using the internal and external shaft clutching mechanism based on spline clutching, the amplitude adjustment andswinging use the same direct current servo motor as a power source so that the structure is much compacter; and by using a cam pair, stepless electric amplitude amplitude is realized.
Owner:SOUTHEAST UNIV
Ground milling machine having a cooling system, cooling system, and method for cooling a ground milling machine
ActiveUS10100712B2High trafficReduce energy consumptionLiquid coolingMachines/enginesAerospace engineering
Owner:BOMAG
Product heat treatment process
InactiveCN108106419AImprove consistencyRealize continuous deliveryFurnace typesEngineeringHeat treated
The invention provides a product heat treatment process for solving the problem of generation of cracks in products, nonuniform density and low heat treatment efficiency in the prior art. The productheat treatment process comprises the following steps: (S1) products are positioned in a first temperature environment for preheating; (S2) the products are positioned in a second temperature environment for roasting or insulation; and (S3) the products are positioned in a third temperature environment for cooling; the first temperature environment and / or the third temperature environment are constant temperatures; the second temperature environment is a constant temperature; and the temperature of the second temperature environment is higher than the temperatures of the first temperature environment and the third temperature environment. The products are transited in the heating and cooling process, so that the condition of extreme cooling and extreme heating is prevented, and the qualityof the products is improved.
Owner:CISDI ENG CO LTD +1
Temperature control system of in-cylinder direct injection gasoline injector
InactiveCN106368870ADirect control of fuel temperatureImprove heating efficiencyMachines/enginesSpecial fuel injection apparatusTemperature controlGasoline
A temperature control system of an in-cylinder direct injection gasoline injector comprises a temperature control module arranged in the gasoline injector and an engine control unit arranged in a cab. According to the temperature control system, fuel oil temperature of the gasoline injector can be collected accurately and compared with the optimal fuel oil temperature, the engine control unit controls a power source to apply required heating electric power to a heating cylinder, and accurate closed-loop control over the optimal fuel oil temperature is achieved.
Owner:SHANGHAI JIAO TONG UNIV
Method for calculating ammonia leakage amount of SCR post-processing system
ActiveCN113202605AGuaranteed accuracyPrecise control of injection volumeInternal combustion piston enginesExhaust apparatusEnvironmental engineeringAmmonia
The invention discloses a method for calculating the ammonia leakage rate of an SCR post-processing system. The method comprises the following steps that S1, a relational expression between a current downstream NOx sensor measurement value and the ammonia leakage rate is obtained; S2, a relational expression between a downstream NOx sensor measurement value before 1s and the ammonia leakage amount is obtained; S3, the current ammonia leakage amount is calculated; a calculated value of the ammonia leakage amount is processed through low-pass filtering; the calculated value of the ammonia leakage amount is corrected according to the change trend of the calculated value of the ammonia leakage amount and an ammonia leakage amount actual value; and when the NOx conversion efficiency obtained through an upstream NOx sensor measurement value and the downstream NOx sensor measurement value is larger than a threshold value, the ammonia leakage amount calculation value is set to be 0. According to the design, the precision of SCR closed-loop control is improved, and the calculation accuracy of the ammonia leakage rate is high.
Owner:DONGFENG AUTOMOBILE COMPANY
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