70results about How to "Not affected by interference" patented technology

The invention provides a device for measuring deflection / displacement line shape by pressure difference and a method thereof. The device comprises a trolley and an L-shaped pipeline filled with liquid, wherein the horizontal section of the L-shaped pipeline is arranged on the trolley along the length direction of the trolley; the two ends of the horizontal section of the L-shaped pipeline are respectively provided with pressure sensors A and B, and the bottom is provided with a temperature sensor; a wheel of the trolley is provided with a displacement transducer; the temperature sensor, the pressure sensors A and B and the displacement transducer are connected with a control system provided with an interface and a memorizer by a data bus; and the displacement transducer is used for controlling the measurement to start for once after the trolley rotates for N rounds. The two pressure sensors are used for measuring the pressure difference at the two ends of the pipeline, and calculating by the liquid density at the different temperatures, thus measuring the vertical altitude difference between two points. The invention has the advantages of wide measuring plane, high accuracy, no influence by light interference, high degree of automation, low measuring cost, etc.

The invention discloses a method for converting a boundary element by an extra-high voltage direct current transmission line mode voltage S, comprising the following steps: when the direct current line is in fault, after a protective element is started, the line mode voltage is obtained by utilizing a phase mode transformational theory according to the two-pole direct current voltage detected on a protection installation part; a dispersion line mode voltage signal is selected to perform S conversion, wherein the sample sequence length is 200 points, and the conversion result is 101*200 time frequency complex matrix; mode calculation is performed on each element in the complex matrix; the high-frequency energy and the low-frequency energy of the line mode voltage are extracted according tothe obtained mode matrix; the ratio of the high-frequency energy and the low-frequency energy of the line mode voltage is calculated; the faults in the cell and out of the cell are distinguished according to the ratio of the high-frequency energy and the low-frequency energy. A large amount of stimulated results prove that the method of the invention has better effect.

The invention discloses a cellular network transmission method based on uplink non orthogonal multiple access relay assistance. The method comprises the following steps: forming a cluster by N users within the coverage of a relay node in a cellular network, wherein the relay is located at the central position of the cluster; the uplink information transmission process of the users in the cluster is as follows: user-relay node-base station. It is assumed that the relay node transmits information to the base station while the user transmits the information to the relay node within a time length T. The user in the cluster transmits the information to the relay node in an orthogonal frequency division multiple access mode on resource allocation, and a single user only occupies on frequency band resource; the relay node works in a full duplex mode, the user information arriving at the relay node is immediately decoded and forwarded to the base station, and an NOMA mode is adopted in the bandwidth resource allocation in the process, and the user information is transmitted to the base station by all bandwidths in the cluster; and numerical simulation results show that compared with the traditional method of merely using the OFDMA uplink transmission method, the user uplink information transmission scheme provided by the invention can effectively improve the spectrum effectiveness of the system.

The invention relates to an EMD (Empirical Mode Decomposition) based boundary element method for ultra high voltage DC transmission lines, which comprises the following steps of: when DC lines break down, after a protective element is started, resolving line-mode voltage by using the phase-mode transformation theory according to DC voltages at both poles measured at the installation position of the protective element; performing EMD on discrete line-mode voltage signals with the sequence length of 100 dots to obtain m IMF (Intrinsic Mode Function) components; on one hand, resolving the absolute value of each IMF component, and on the other hand, carrying out Hilbert transformation on each IMF component subjected to EMD to work out an instantaneous frequency; dividing the product of the absolute value of an instantaneous amplitude and the corresponding instantaneous frequency by a sampling frequency to obtain an instantaneous kt value; adding m instantaneous kt values together; and taking the maximum in time-domain space as the ultimate criterion k to distinguish faults in or outside areas. A large number of simulation results show that the method has good effect.

The invention provides a distribution network fault line selection method using form peak valley detection, comprising the following steps of: when a distribution network line occurs faults, starting a line selection device, according to the three-phase current of each line measured at a protective installation place, determining a zero-sequence current of each line by using a Clark transforming theory; selecting a zero-sequence current signal of which the time window is 10 ms, solving envelope lines, and detecting the form peak valley to the envelope lines of the zero-sequence current of each line; according to the obtained characteristics of the form peak valley, extracting fault line selection criterions of the distribution network, wherein the line with the form peak valley characteristics different from that of other lines is the fault line. The method in the invention is simple for calculating, and avoids the defects that a common calculating method needs transforming in time-frequency domains. The method is good in robustness, strong in transition resistance force, free of interference influence, and strong in practicability. A large number of simulation results show that the method of the invention is accurate in line selection.

The invention discloses an integrated underwater thruster driving system and a control method, which realizes the integrated underwater thruster sensorless control. A linear back EMF sliding mode observer based on fuzzy switching gain adjustment is provided, The observer adopts a smooth hyperbolic tangent function and fuzzy rules to realize change of a gain value and reduce the chattering of the system, so that the control system can obtain smooth back EMF estimates without adding a low pass filter and a phase compensation module, thus avoiding the phase lag of the back EMF estimates. The lineback EMF estimates are corresponded to three virtual Hall signals and six discrete commutation signals are obtained directly without the need of fixed phase shift circuit and calculation of phase shift angle. the invention realizes the integrated underwater thruster sensorless control by estimating the line back EMF of the brushless DC motor loaded in the underwater thruster,.

The patent refers to the field of 'measuring of length, thickness, or similar linear dimensions and angles, areas,irregularities of surfaces or contours'. The invention discloses an automatic axial internal clearance measuring meter for a tapered roller bearing of an automobile gearbox. The measuring meter is characterized by consisting of a frame (10), a workbench (9), a lower external pedestal (27), a lower rotating shaft (21), a lower internal table (20), a driven pulley (38), a steel ball (40), a speed regulating motor (2), a driving pulley (43), a pulley (44), a tensioning component (35), a load hanging plate (32), a lower load bracket (31) capable of moving up and down, a load rod (30), a load (29), a measurement hanging plate (22), a meter clip (24), an inductance measuring head (23), a measuring lever (25), a bracket (3), a yoke plate (5), a compressing cylinder (12), a bearing housing (6), a movable plate (4), a door-shaped bracket (8), a guide rod (7), a pressurizing cylinder (13), an upper external pedestal (16), an upper rotating shaft (15), an upper internal table (18), an air supply system and an electric operation box (14). The automatic axial internal clearance measuring meter ensures the safety and reliability of the bearing by controlling the accuracy of the axial internal clearance of the gearbox so as to meet the requirements on high load and high efficiency of the automobile gearbox and ensure driving safety of the automobile.

The invention relates to a method for judging internal and external faults of an alternating current transmission line based on a fractal dimension, and belongs to the technical field of relay protection of electric power systems. The method comprises the following steps of: when an alternating current line fails, selecting fault component voltage, and decoupling by new phase-mode transformation to obtain line mode voltage, wherein sampling frequency is 1MHz, and a time window is 1ms; selecting a discrete line mode voltage signal with the sampling sequence length of 1,000 points; fracturing by a sampling box dimension method to obtain a fractal dimension D of the fault component voltage; and distinguishing the internal and external faults according to the fractal dimension, determining that the fault is the external fault when the D is less than or equal to 1.2, and determining that the fault is the internal fault when the D is more than 1.2. The sampling frequency is 1MHz, the time window is 1ms, required data has a small length, and the method is low in calculated amount and high in real-time performance; and whether the faults occur in an area is only judged by single end amount without channels, and the method is relatively high in practicability. A large number of simulation results prove that the method is high in transition resistance tolerating capacity, is suitable for different fault types and has an obvious effect.

The invention provides a video monitoring system based on the internet of things, and relates to the field of the video monitoring. The problem that the existing internet of things needs to reconstruct an internet of things base station can be solved. The video monitoring system comprises a cloud server, and at least one communication base station connected with the cloud server, wherein each communication base station is connected with at least one set of video processing equipment; the video processing equipment and the video monitoring equipment are in one-to-one corresponding connection, each communication base station is loaded on lighting equipment, and each communication base station and the connected video processing equipment and video monitoring equipment form a local area network. The video monitoring system is used for the video monitoring.

The invention is a video display unit for automobile monitoring system, transmitting monitored data of camera and backing-up radar installed on an automobile to a digital video decoder and a microprocessor, where the digital video decoder decodes the video data into specific data format to send to a timing controller which combines the video data of the specific data format with obstacle distance data sent from the microprocessor and then sends the combined data to a digital video coder to reduce to analog signal to output to a display for displaying, and a complete independent monitored video, an obstacle distance value display region and an obstacle distance variation animation are generated on the display; by the above technique, the invention provides a display interface with affinity, making a driver able to more effectively know the peripheral conditions but not disturbed and influenced visually.

The invention discloses a processing system, a method and a hand-held terminal for translating displayed text information, the hand-held terminal is adopted for getting the text information which is displayed according to original language from an electronic display board through the short-distance wireless transmission way, finding the corresponding target language of the text information which is displayed according to the original language through the preset information of a multi-language text library, translating the got displayed information to target text and displaying the target text on the handheld terminal, and the near field communication (NFC) way is adopted for translating the text information displayed according to the original language to the text information in the target language of a user in a real-time manner, thereby providing convenience to the user, avoiding being affected by environmental interference, being strong in applicability and reducing the cost. The hand-held terminal can also be used for connecting to wireless Internet, thereby performing on-line updating and upgrating on language text packs. Furthermore, by adopting the invention, the text information displayed in the various languages can be simultaneously translated to translation in the target language of the user with high efficiency.

This invention relates to time simultaneous code address direct state to realize the upper and down row switching method, which comprises the following steps: control center getting the base state position information and two switching time information through wireless network controller or base state; then sending the information to the computing and control module through communication linkage; compute and control module using satellite positioning receiver to get the direct state position information and standard time to get the wireless wave transmission delay and then to compute the accurate state conversion time spot and to generate control signals to control the switching of the linkage.

The invention discloses a global synchronous pulse width modulation self-synchronization method in the communication failure state, and by means of the method, grid-connected inverters can still maintain the global synchronous operation state under the circumstance of communication failure, the states of all the grid-connected inverters are not needed to be changed, and the advantages of the global synchronous pulse width modulation method are given full play. The method comprises the steps that a global synchronization unit sends a synchronizing signal to the grid-connected inverter M and sends the synchronizing signal transmission frequency fsyn to the grid-connected inverter M, and the grid-connected inverter M calculates out the crystal oscillator error between the grid-connected inverter M and the grid-connected inverter 1 according to the synchronizing signal; the grid-connected inverter M sets self-synchronization parameters according to the calculation result; the grid-connected inverter M predicts the moment when the synchronizing signal appears next time according to received delta Tsyn, if the synchronizing signal appears, a communication system works normally, self-synchronization is not needed to be conducted, if the synchronizing signal does not appear, communication system failure occurs, and the grid-connected inverter M conducts self-synchronization.

The invention discloses a primer for simultaneously detecting pasteurellamultocida and a capsularA type dual real-time fluorescentquantitative PCR method of the pasteurellamultocida and application, and relates to the technical field of biology. The primer adopts Kmt-F: 5'-GCTYGTTGTGAGTGGGCTTGT-3'; Kmt-R: 5'-GCCGTTGTCAAGGAAGCAGAT-3'; Kmt-P: 5'-FAM-TTTGTTGGGCRGAGTTTGGTG- BHQ13'; CapA-F: 5'-GGGCTGGCTATGTTGGTTTAT-3'; CapA-R: 5'-CTTTATCTGTGATGGGCGATT-3';CapA-P: 5' HEX-TAGCTCAACACCACAATGTGATCT-3'. The primer simultaneously detects kmt1 and hyaD-hyaD genes.

An object deformation early warning monitoring system and method are disclosed. The system comprises a plurality of light emitting and receiving nodes, a receiving controller, and a processing unit. The plurality of light emitting and receiving nodes and the receiving controller are successively arranged at an object monitoring point. Two paths of light are emitted from the first light emitting and receiving node to the next light emitting and receiving node. The first path of light is an encoded light beam after encoding and encryption. Starting from the second light emitting and receiving node, each light emitting and receiving node decodes and proofreads the received encoded light beam through a light decoding detection controller arranged on the node. After proofreading is successful,forwarding is performed and finally the light beam is transmitted to the receiving controller. The second path light is a continuous non-coding light beam, which is successively forwarded by the plurality of light emitting and receiving nodes, and finally is transmitted to the receiving controller. Displacement or deformation alarm is issued only when the first and second paths of light is not received by the receiving controller. In the invention, system false alarm is greatly reduced, the system and the method are not influenced by an external light interference, and long distance monitoringis realized.

The invention discloses an electric energy quality detection method on the basis of generalized morphological open-close and close-open wavelet transform, which comprises the following steps: 1, acquiring a signal for electric energy quality detection and carrying out normalization; 2, carrying out a first layer of generalized morphological open-close and close-open wavelet transform processing on the normalized sginal and then extracting signal characteristics of a trapped wave and transient oscillation; 3, carrying out a second layer of generalized morphological open-close and close-open wavelet transform processing on an approximate signal obtained after the first layer of generalized morphological open-close and close-open wavelet transform processing and then extracting signal characteristics of a harmonic wave; 4, carrying out a third layer of generalized morphological open-close and close-open wavelet transform processing on an approximate signal obtained after the second layer of generalized morphological open-close and close-open wavelet transform processing and then extracting signal characteristics of voltage swell, temporary voltage drop and voltage momentary interruption; 5, according to the extracted signal characteristics, judging electric energy quality. The electric energy quality detection method has the advantages of small calculated amount, high response speed and strong resistance to noise interference.

The invention relates to an automatic return gear for a motor of an intelligent electronic type contactless two-way rotary windscreen wiper. The gear is mounted at an end cover of the motor body; an origin positioning steel magnet and an inflection point positioning steel magnet which rotate with the gear are embedded on the gear and move along two different circumferences of the same gear. The automatic return gear is applied to the intelligent electronic type contactless two-way rotary windscreen wiper and overcomes the long-existing defects that a mechanical contact type motor is cumbersome in structure, short in service life, high in failure rate, unstable in quality, difficulty in mounting. Moreover, no interference radiation is generated during the operation of the motor, and other electronic equipment in the vehicle can be protected from interference. Especially, a transmission assembly structure in a windscreen wiper assembly is eliminated. Therefore, due to the adoption of the automatic return gear, the windscreen wiper assembly is simpler in structure and lower in using cost. The automatic return gear fills the blank home and abroad in the field of motor industry of the automobile windscreen wipers.

The invention discloses a safety sealed detonation device and a safety detonation method, belonging to the construction field of oil-gas well perforating operation and building foundation pit blasting, and aiming to solve the problem that the traditional detonator cannot realize integrative sealing. The device comprises a detonation device lifting pipe fitting, a pressure relief and chip removal hole, a positive sealing device, an explosion joint, a firing gear crash helmet, a firing gear, a miniature detonation device, a detonation propagating device and a negative sealing device, wherein the miniature detonation device and the firing gear are arranged on the detonation propagating device in order; the firing gear crash helmet is buckled on the firing gear, and the positive sealing device is arranged between the firing gear and the explosion joint; the detonation propagating device comprises a detonation propagating shell, a booster primer and an energy cavity, the energy cavity is positioned in the bottom of the detonation propagating shell, and the booster primer is arranged in the detonation propagating shell. The device self is wholly sealed, can still keep good leakproofness and detonation capacity in the under environment, and is not easy to be affected with damp and lose efficacy after meeting water.

The invention relates to a temperature, pressure and humidity monitoring sensor, which belongs to the technical field of environment monitoring and solves a problem that the existing temperature, humidity and pressure sensor cannot simultaneously output analog and digital signals. The temperature, pressure and humidity monitoring sensor comprises a shell, an electrical connector and a threaded base; the threaded base and the electrical connector are respectively welded together with the shell to form a closed cavity; a sensing module, a signal processing module and a signal interface module are arranged in the shell, and the sensing module is used for acquiring inner and outer pressure, temperature and humidity in environment in real time; the signal processing module is used for analyzingand processing the acquired environment information; and the signal interface module is used for transmitting digital and analog signals to the outside. According to the temperature, pressure and humidity monitoring sensor provided by the invention, a sensor technology and a microprocessor technology are combined organically, a plurality of functional modules are integrated on the sensor, the environment can be acquired in real time and processed, high-precision real-time monitoring for absolute pressure, relative pressure, humidity and temperature of a tested environment can be realized, anddata output is provided through analog and digital modes.

The invention relates to an unmanned system space positioning method based on an LED light source. A positioning device involved in the method comprises LED light sources with identity information, anoptical detection component, a data processing board and a software algorithm. The LED light sources distributed in the motion space of an unmanned system emit optical signals with identity information, the data processing board drives optical detection components on the unmanned system to collect the spatial position and identity information of each LED light source under the control of a software algorithm, and the software algorithm analyzes the self-positioning of the unmanned system from the information. The indoor and outdoor space positioning method is provided for the unmanned systemby utilizing the LED light sources with the identity information, and the method can independently become a space positioning mode of the unmanned system, and can also become a calibration means for positioning modes such as satellite positioning, visual positioning, laser slam positioning, ultrasonic navigation positioning and aircraft calculation positioning.

The invention relates to the technical field of radioactive substance content measurement, aims at solving the problem that a tritium content measuring device in the prior art is relatively low in precision of the measurement result, and provides a tritium content measuring device comprising a sample unit and a contrast unit. The sample unit sequentially comprises a first temperature control chamber, a first measuring structure and a sample room from exterior to interior. The contrast unit sequentially comprises a second temperature control chamber, a second measuring structure and a contrast room from exterior to interior. The second temperature control chamber and the first temperature control chamber are the same in structure, the contrast room is arranged in the second temperature control chamber; and the second measuring structure used for measuring heat radiation power of the contrast room to the second temperature control chamber is arranged between the second temperature control chamber and the contrast room. The sample room is inside provided with a first checking heat source, the contrast room is inside provided with a second checking heat source, and the first checking heat source and the second checking heat source both can adjust the heating power. The invention also relates to a tritium content measuring method based on the above tritium content measuring device. The beneficial effect of the tritium content measuring device and method is that the measurement result is relatively-high in precision.

The present disclosure provides an air conditioning controlling system based on the Internet of Things, and relates to the technical field of the Internet of Things. The problem that a base station ofthe existing Internet of Things needs to be re-established is solved. The air conditioning controlling system based on the Internet of Things includes a cloud server and at least one communication base station connected with the cloud server; and each communication base station is connected with at least one data processing equipment, the data processing equipment is connected with air conditioner control panels in a one-to-one corresponding mode, each communication base station is mounted on one lighting equipment, and a local area network is formed by each communication base station, at least one data processing equipment and at least one air conditioning control panel, wherein the data processing equipment is connected with the air conditioning control panel in a corresponding mode. The air conditioning controlling system is used for controlling air conditioners.

The invention discloses an intelligent electric control device for an electric door lock based on RFID and a working method thereof. The device comprises an RFID remote controller, an RFID decoder, a logical judgment circuit, an electric lock switch control circuit, a silence control circuit, an electric lock state feedback detection circuit, a buzzer warning circuit and a storage battery state detection circuit. According to the invention, the device is kept in a normally closed lock state when no operation is executed after electrifying, so that the locking state of a vehicle door can be kept after the power supply of the device recovers the normal power supply under the condition of accident outage or unstable instantaneous voltage. The logical judgment circuit, the electric lock state feedback detection circuit and the electric lock switch control circuit of the device are all arranged as double-loop redundant protecting circuits, and the damage to one circuit can not result in control failure. The device disclosed by the invention is suitable for an economical RFID intelligent electric control device adopted by the railway industry; the intelligent electric control device can be used together with a common electric door lock; and an RFID radio-frequency signal is not interfered while the safety and reliability are ultrahigh.

The invention provides a semiconductor sensor reverse packaging process. The semiconductor sensor reverse packaging process comprises a reverse packaging pin, a reverse packaging base island, a reverse packaging chip and a reverse packaging plastic sleeve. The semiconductor sensor reverse packaging process comprises the following steps: S1, preferentially aligning the reverse packaging chip to a connecting surface of the reverse packaging base island; s2, performing tin soldering connection on the circuit end of the reverse packaging chip and the circuit end of the reverse packaging base island; and S3, fixing the top of the reverse packaging base island in a reverse concave structure of the pin. The semiconductor sensor reverse packaging process provided by the invention has the advantages that reverse molding is carried out when components are subjected to plastic package molding, and the semiconductor sensor chip is structurally kept at the bottom position of the frame, so that after the semiconductor chip in a plastic package body enters a ceramic substrate, the sensor part is still in the front direction of the whole module, so that the function of the sensor is realized; and meanwhile, the reverse sealing process can realize the normal line signal connection between the sensor type component and other universal PCBs, and the sensor type component is not influenced by the interference of other external signals.

The invention discloses an insect antifeedant 15beta-hydroxyklaineanone conducted in plants and application. The 15beta-hydroxyklaineanone has antifeeding activity on various insects and can be conducted in the plants; the antifeeding effect is better than that of the antifeedant applied to the surfaces of the plants; the 15beta-hydroxyklaineanone can be used for preparing a systemic insect antifeedant, is more convenient to use, is not influenced by interferences of an external environment and has a good application prospect; the insect antifeedant is separated and purified from natural plants and has low toxicity, no residues, no pollution and no nuisance on economic crops including various grains, melons and vegetables; a series of problems produced by the drug resistance caused by traditional insecticide in the prior art can be solved.

The invention relates to an online detection method of a grounding resistor. The voltage and the current of the grounding resistor to be measured are measured through an auxiliary electrode embedded system, and the measured voltage signal and the measured current signal are transmitted to a measuring system, wherein the auxiliary electrode embedded system is of a sealed structure. Data processing is performed on the received voltage signal and the received current signal through the measuring system. The resistance value of the grounding resistor is obtained, and the measured resistance value of the grounding resistor is locally displayed or transmitted to a master station management control system. The resistance value of the grounding resistor is displayed and managed by the master station management control system. The online detection method of the grounding resistor effectively solves the problem existing in measurement of grounding resistors in the prior art, achieves efficient and real-time online measurement of grounding resistors, is not limited by the site or influenced by environmental interference, greatly improves the measuring accuracy, greatly reduces manual error, is favorable for finding out problems as soon as possible to take measures in time for maintenance, and thus guarantees safe operation of relevant lightning protection system equipment and the like.

The invention relates to an electronic non-contact bidirectional rotary intelligent wiper motor (called NIM for short) based on a current international and domestic universal mechanical contact motor. The wiper motor overcomes the shortcomings that the mechanical contact motor is cumbersome in structure, short in service life, high in failure rate, unstable in quality, difficult to mount and the like for a long time, interferential radiation cannot be generated when the wiper motor runs, other electronic devices in an automobile are protected from interference, and a structure of a transmission assembly in a wiper assembly is particularly omitted, so that the wiper assembly is simpler in structure and lower in use cost. The wiper motor fills up international and domestic gaps of the field of an automobile wiper motor industry.

The invention provides a multifunctional environment simulation test device capable of real-time observation, and the device comprises a box body which is internally provided with a space for accommodating a sample, one side of the box body is provided with a box door which can open or seal the space, and the top of the box body is provided with a transparent observation window; the device furthercomprises a controller arranged in the box body; sensors which are arranged in the box body, are electrically connected with the controller and at least comprise a temperature sensor, a humidity sensor and a sulfur dioxide concentration sensor; actuators which are arranged in the box body and are electrically connected with the controller; and a control panel which is electrically connected withthe controller and is used for inputting parameter values; the controller controls the actuators such that the values monitored by the sensors are equal to the input corresponding parameter values. Therefore, a plurality of adjustable and controllable parameters can be set, the weathering test of grotto cultural relics under the multi-factor coupling effect is realized, the closed space can ensurethat the test is not influenced by external interference, and meanwhile, the process can be observed in real time through the observation window.

The invention discloses an expanding defoaming and dredging dry-type evaporator for a water cooled centrifuge unit. The dry-type evaporator comprises a grooved drum shell, an exhaust duct, air coolingboxes, a water cooled spray pipe, an aluminium plate heat exchange tank, a drainage pipeline and an outer propeller rotating disk; the exhaust duct and the drainage pipeline are welded with the upperand lower sides of the middle section of the grooved drum shell separately, and interpenetrate with each other; and the two air cooling boxes are provided, and installed at the right and left top corners of the water cooled spray pipe separately. According to the dry-type evaporator, through cooperative application between the outer propeller rotating disk and a fluidized bed plate, the outer propeller rotating disk is pushed by air pressure of a blower to rotate, so that a brush rotating frame is rotated on a film in an external expansion manner for brushing away steam foam; then, the foam is removed under the internal and external centrifugal air pressure of a concave corrugated groove and diaphragm blades; when the foam attaches to the fluidized bed plate, the foam is discharged with water flow, while air force is recoiled upwards for taking away hot air; and the effects of foam dredging and exhaust as well as up-and-down cyclone gas-liquid separation are achieved, and the functionof covering and removing the foam in the evaporator in a self-propelled pneumatic external expansion manner is achieved.