44results about How to "Avoid overlapping" patented technology

The invention provides a K-band broadband dual circularly polarized antenna applied to the satellite internet, and belongs to the field of circularly polarized antennae, the K-band broadband dual circularly polarized antenna comprises a radiation unit, a first dielectric layer, a metal ground layer, a bonding layer, a second dielectric layer and a feed network which are stacked from top to bottom, the radiation unit comprises two first radiation patches and two second radiation patches, the first radiation patch is provided with two long rectangular grooves which are vertically intersected, the second radiation patch is provided with two short rectangular grooves which are vertically not intersected, the first radiation patch and the second radiation patch are respectively connected to the metal ground layer through metal columns, and the metal ground layer is provided with a first coupling gap and a second coupling gap. A first rectangular groove, a second rectangular groove, a third rectangular groove and a fourth rectangular groove are formed in the metal ground layer, and the feeder network comprises a first microstrip feeder and a second microstrip feeder; the antenna structure is low in profile, wide impedance bandwidth can be achieved, and the two feed ports can work in the same frequency range.

The invention discloses an iron sheet machining device for a road guardrail, and relates to the technical field of guardrail iron sheet machining. Comprising a first supporting frame, a transverse translation mechanism is installed on the first supporting frame, and a laser cutting assembly used for cutting an iron sheet body is installed at the bottom of the transverse translation mechanism; the auxiliary conveying mechanism is used for auxiliary conveying of the iron sheet main body; the detection mechanism is used for detecting the position of the iron sheet main body; and the control module is based on detection information of the detection mechanism. Through the arrangement of the detection mechanism, the supporting and positioning assembly and the control module, the detection mechanism can be used for detecting the position and distance of the reinforcing ribs, and the control module controls the adjusting part to adjust the position of the wheel carrier on the supporting table so as to adapt to the distance of the reinforcing ribs, so that the iron sheet main body can stably move in the conveying process; and meanwhile, the cutting reliability is guaranteed.

The invention relates to a furniture three-dimensional reconstruction method, which comprises the following steps: collecting sparse point clouds of furniture, and obtaining a Gaussian ellipsoid set according to the sparse point clouds; obtaining Gaussian ellipsoids to be split in the Gaussian ellipsoid set, and determining the positions of the central points of the two Gaussian ellipsoids to be generated based on the cumulative gradient of the Gaussian ellipsoids to be split and the distribution of the Gaussian ellipsoids in the neighborhood, according to the shape of the Gaussian ellipsoid to be split and the neighborhood of the two split Gaussian ellipsoids, the shapes of the two split Gaussian ellipsoids are determined; obtaining a Gaussian ellipsoid to be cloned in the Gaussian ellipsoid set, and determining the position of the central point of the Gaussian ellipsoid generated by cloning based on the distribution of the Gaussian ellipsoid in the neighborhood of the Gaussian ellipsoid to be cloned; and storing the trained Gaussian ellipsoid set, and performing three-dimensional reconstruction on furniture by using the stored Gaussian ellipsoid set.

The invention discloses a wiring method and device for a chip layout, equipment and a storage medium, and particularly relates to the technical field of quantum. The method comprises the steps that wiring from a first wiring port to a second wiring port on a chip layout is determined, the wiring comprises tangent segments and arcs which are alternately connected, the straight line where the tangent segments are located is tangent to the circle where the arcs connected with the tangent segments are located, each arc takes a vertex on the chip layout as the circle center and bypasses a component corresponding to the vertex, and the tangent segments are arranged on the first wiring port and the second wiring port; the vertex is a point corresponding to a component passed between the first wiring port and the second wiring port; arcs included in the wiring are identified, a target arc is determined, the target arc refers to an arc with a rotation phenomenon, and the rotation phenomenon refers to that the central angle corresponding to the arc is larger than a threshold value; and removing the target arc, and adjusting the wiring to obtain the adjusted wiring. According to the method, the wiring accuracy is improved.

The invention discloses an EUV mask defect detection device, which comprises a bottom plate, a first base, a mounting bracket, a displacement assembly and a main vacuum assembly, the first base is fixed on the bottom plate, the mounting bracket is fixed on the top of the first base, the main vacuum assembly is fixed on the top of the mounting bracket, and the displacement assembly is fixed on the bottom plate. The bottom of the main vacuum assembly is connected with the first base through a displacement assembly, and the displacement assembly is used for adjusting the Z-direction position of the main vacuum assembly. The device further comprises a second base, a triangular support and a scanning vacuum assembly, the second base is fixed to the bottom plate, the triangular support is fixed to the top of the second base, the scanning vacuum assembly is fixed to the triangular support, and the scanning vacuum assembly is connected with the main vacuum assembly through a corrugated pipe. According to the invention, the scanning vacuum cavity is separated from the main vacuum cavity, rigid connection is avoided by using the corrugated pipe, and the problem that the imaging quality is influenced by vibration caused by scanning in the exposure process is solved.

The invention discloses an integrated circuit testing machine with a material stacking prevention function and a testing system, and the integrated circuit testing machine comprises a testing head and a host. The integrated circuit testing machine is used for cooperating with the classifier. And the test head is used for placing the tested object on the classifier and taking back the tested object by the classifier. The host is used for executing a test program on the tested object through the test head and providing a first instruction to enable the classifier to operate in a replacement stage. In the replacement stage, the classifier firstly executes the retrieval program and then executes the placement program so as to be replaced with another tested object. Wherein the host is used for executing the residual test program through the test head in the replacement stage, and generating a second instruction for stopping the operation of the classifier when the tested object is left on the test head. Therefore, the problem of material stacking caused by the abnormality of the classifier can be solved without increasing the test time.

The utility model relates to the technical field of twill roll rotary discharging devices, and discloses a twill roll rotary discharging device which comprises supporting legs, a base fixedly connected to the upper sides of the supporting legs, a rolling table fixedly connected to the upper side of the base, cloth fixedly connected to the rolling table, supporting rollers fixedly connected to the upper surface of the base and a rotary discharging box. A flattening mechanism and a spreading mechanism are arranged on the upper side of the base, the flattening mechanism is arranged on one side of the spreading mechanism, the flattening mechanism comprises a support, the support is fixedly connected to the upper surface of the base, the flattening mechanism is used for flattening cloth, a user can conveniently cope with more use scenes, the mechanism can adjust the distance between rotating rods, and therefore the cloth can be flattened. The flattening mechanism is used for flattening cloth, so that the flattening force can be adjusted, the spreading mechanism is used for turning over and spreading the cloth during discharging, manual turning operation of workers is replaced by the mechanism, the cloth cannot be gathered during turning through cooperation between spiral blade rods, and the device can run for a long time.

This invention provides a heat treatment method for stainless steel reed wire, relating to the field of reed wire heat treatment technology. The vertical take-up device includes a support frame and a rail; a movable component is mounted on the rail, and a winding structure is fixedly mounted on the top of the movable component; a wire transfer drum is fixedly mounted at the bottom of the vertical shaft, and the reed wire body is spirally wound around the outside of the wire transfer drum; auxiliary structures are provided on both sides of the top of the support frame, and a guide component is fixedly mounted on the outside of the support frame; precise wire guidance is achieved through the upper and lower guide rollers of the guide component, and the wire is clamped and fed by the wire transfer drum and auxiliary rollers, preventing wire deviation, shifting, and tangling from the source; the auxiliary structure can adjust the clamping force on the reed wire body, ensuring constant tension, tight and uniform wire arrangement, and neat coiling during the winding process, facilitating subsequent transportation, straightening, and stamping processing, thus solving the problems of wire deviation and shifting.

The present application relates to the technical field of machining, and provides a workpiece surface net texture machining method, which comprises the following steps: determining the diameter of a net texture machining tool according to the width of a to-be-machined surface; setting the offset distance of a cutting track relative to the center line of the to-be-machined surface, so that the phase angle of the formed net texture is in a preset uniform interval; converting the turning intersection point of the cutting track into a tangent circular angle, and the radius of the tangent circular angle matches the radius of the net texture machining tool; and machining by the net texture machining tool according to the cutting track. Through the synergistic control of the above macro track offset and micro intersection point circular angle conversion, the present application solves the problem of uneven distribution of net texture caused by the lack of systematic process method in the prior art, and realizes high-quality net texture machining with a grid approximately square and overall uniform.

The application discloses a large-interval wide-angle scanning phased array antenna design method and system, and belongs to the technical field of array antenna design. The application adopts parameterized setting of block number to improve the degree of freedom of optimization. Since each block condition may exist a better solution, the block type of the region is substituted into the optimization variable, so that the final optimization result can be prevented from falling into a local optimum, and the optimal solution can be more likely obtained. The dense arrangement form of the divided region can effectively control the interval of adjacent array elements, avoid the overlapping of adjacent array elements, and improve the optimization efficiency. In addition, the regular layout is beneficial to the back-end network design, and reduces the complexity of the feed network. The dense arrangement and array element selection combination can effectively enlarge the interval, and can make the interval not appear grating lobe, thereby reducing the number of channels and reducing the cost. The array element position micro-adjustment provides more possibilities for large-angle scanning optimization, improves the optimization efficiency, and breaks the periodic arrangement form.

The utility model relates to the technical field of full inspection machine feeding devices, in particular to an electronic chip CCD full inspection machine feeding device which comprises a feeding hopper, a first conveying device is arranged at the bottom of the feeding hopper, a separation barrel is arranged at one end of the first conveying device, and a separation mechanism is arranged in the separation barrel. The separating mechanism comprises a motor, and the motor is embedded in the center of the top end of the separating barrel. The electronic chips are guided into the feeding hopper, guided by the guide block and matched with the first conveying equipment to be conveyed into the separating barrel, the driving rod is driven by the motor, the pushing block pushes the electronic chips to conduct centrifugal motion, and therefore the electronic chips slide outwards and slide out of an outlet of the separating barrel to be separated one by one, manual taking and placing of the electronic chips one by one are avoided, and the efficiency is improved. And three groups of mounting racks and second conveying equipment are arranged, so that three single separated electronic chips can be conveniently conveyed to the corresponding full inspection machine at the same time, and the detection efficiency is improved.

The utility model relates to a fishing net technology field discloses a fishing net traction device, including ground, the top left side fixed connection of ground has a plurality of support rod, the top fixed connection of support rod has support board no.

The utility model relates to battery technical field discloses circuit board, battery and terminal equipment, and circuit board includes: board body, first connecting assembly and second connecting assembly, board body includes main body and staggered arrangement at least one first extension and second extension of main body, first extension and second extension are arranged in any one side of main body respectively, and first extension and second extension can all fold towards main body, first connecting assembly sets up in first extension, second connecting assembly sets up in second extension, the utility model adopts the extension of board body to bear first connecting assembly and second connecting assembly, can spare more cloth piece arrangement space for main body, in addition, since first extension and second extension can fold towards main body and staggered arrangement, both can avoid the interference of extension when folding, simultaneously also can avoid the circuit of first connecting assembly and second connecting assembly on the same plane forms the overlap.

This invention discloses a three-degree-of-freedom autocollimation angle measurement device and method based on a crosshair reticle, comprising a probe system, a target mirror system, and a calculation system. The probe system emits a collimated beam containing crosshair image information into the target mirror system. The target mirror system separates the collimated beam containing crosshair image information into two reflected beams parallel to the optical axis, each reflecting beam containing crosshair image information. The probe system also receives the two reflected beams parallel to the optical axis and images the crosshair images corresponding to the two reflected beams. The calculation system calculates the pitch and yaw angles of the target based on the initial and current coordinates of the crosshair image corresponding to one reflected beam parallel to the optical axis, and calculates the roll angle of the target based on the initial and current tilt angles of the crosshair image corresponding to the other reflected beam parallel to the optical axis. This invention enables rapid and high-precision three-degree-of-freedom angle measurement of distant targets.

The application discloses a paper feeding mechanism of a hot stamping die cutting machine, a plurality of fans in an array are arranged in a power cavity, a through hole is arranged to communicate the power cavity with a suction cavity, a buffer cavity is communicated with the bottom of the power cavity, and an exhaust pipe is communicated with the side wall of the buffer cavity; the opening of the suction cavity is located below the gap between the two ends of a conveying belt, a slide is arranged at the middle position of the inner wall of an outer box body, an inner box body for containing paper is slidably installed on the slide, the linear speed of a paper guide wheel is smaller than that of a conveying wheel, the paper is automatically pulled apart in the front-back direction when the paper is separated from the inner box body, the built-in fan array and the buffer cavity are designed to form uniform laminar negative pressure, and the suction cavity is matched to provide appropriate suction force for paper with different gram weights and prevent the paper from drifting; the relative displacement generated by differential speed conveying automatically pulls apart the front and back paper by a safe distance, and double paper overlapping is physically eliminated; a lateral paper filling structure is matched with a sensor control to realize automatic paper replenishment without shutdown, and paper changing time is shortened to zero.

This utility model provides a steel strip butt welding machine, relating to the technical field of steel strip butt welding machines. The machine includes a butt welding machine with a welding head and a switch on its side. A fixing clamp is also provided on the side of the machine, positioned on both sides of the welding head. A locking element is rotatably connected to the bottom of the fixing clamp. A motor is fixedly connected inside the machine. A grinding wheel, driven by the motor, is also provided on the side of the machine. A pressing device and an alignment device are also provided on the side of the machine. The alignment device includes a rectangular frame fixedly connected to the side of the machine, with a threaded rod rotatably connected inside the rectangular frame. A slider is threadedly connected to the surface of the threaded rod, and a rectangular strip is fixedly connected to the side of the slider. This utility model solves the problem of steel strip misalignment during the butt welding process due to operator hand-held operation.

The utility model belongs to the technical field of lid making machinery, disclose a kind of three knives lower lid mechanism suitable for big lid type, including support plate, the top of support plate is equipped with blanking hole, the top of support plate is fixedly installed with pedestal, the center of pedestal is equipped with discharging hole corresponding blanking hole;Three evenly distributed installation ports are equipped on the outer side of the circumference of discharging hole of the pedestal, and one lid separating wheel is arranged in each installation port.The scheme provides a kind of three knives lower lid mechanism, three lid separating wheels are evenly arranged on circumference, the restraining force to lid body is enhanced using three-point positioning principle, unified screw rotation is realized by synchronous driving device, and the stable separation of lid body is realized by the rotary motion of screw dividing slot, to avoid the phenomenon of stuck lid or stacked lid.The mechanism is simple in structure and stable in operation, and is particularly suitable for the automatic production line of big lid type.

The application discloses a method and system for forming an elliptical particle accumulation body, and applies to the fields of geotechnical engineering and material science technology, and comprises the following steps: defining a space boundary and a calculation rule; generating and placing bottom-layer elliptical particles in a left-to-right placement order: determining a circular arc segment in contact with a container boundary line, and determining the center of a first bottom-layer elliptical particle based on translation and offset calculation of a left boundary and a lower boundary; randomly generating a bottom-layer elliptical particle, forming an intrusion block with a previous elliptical particle, and performing placement judgment of the bottom-layer elliptical particle based on line segment information after offset of the lower boundary and the right boundary of the container; generating and placing upper-layer elliptical particles: randomly generating an upper-layer elliptical particle, traversing a current accumulation body surface elliptical particle set to form a corresponding intrusion block, and performing placement judgment of the upper-layer elliptical particle based on line segment information after offset of the left boundary, the right boundary and the upper boundary of the container. The application realizes generation of an elliptical particle accumulation body with high density and low porosity.

This utility model relates to the field of ceramic body drying technology and discloses a multi-layer microwave-assisted continuous drying line for ceramic bodies. It includes a cover, with multiple sets of support components arranged equidistantly at the lower end of the cover to support the ceramic bodies. A base is located at the lower end of each support component, and a cavity is provided inside the base. The sidewalls of the cavity edges are movably supported on the bottom of the support components. Boxes are positioned between each pair of the equidistantly arranged support components. A rotating component is located on the side of the cover. By placing the ceramic bodies on multiple sets of support components, the ceramic bodies do not interfere with each other, preventing them from overlapping and significantly reducing microwave penetration and causing uneven drying. The rotating component allows the ceramic bodies inside the multiple sets of support components to rotate as a whole, further accelerating the heating and drying time, ensuring more uniform heating and drying, and saving energy.

This utility model relates to the field of fiber twisting technology, specifically a PET fiber twisting device, including a frame, a drive mechanism and a base fixedly mounted on the frame, a twisting mechanism rotatably mounted on the base, the twisting mechanism including a steel ring and a mandrel, the steel ring fixedly connected to the base, a twisting ring slidably mounted on the steel ring, the mandrel fixedly mounted on the drive mechanism, the mandrel rotatably connected to the base, a yarn bobbin sleeved on the mandrel, the inner wall of the yarn bobbin having several protrusions fixedly connected in an annular shape at equal intervals, the protrusions engaging with the mandrel; by engaging the protrusions with the yarn bobbin, it is ensured that the yarn bobbin rotates synchronously with the mandrel, avoiding slippage causing interruption of material supply; the steel ring provides a stable sliding track for the twisting ring, and together with the rotational power of the mandrel, ensures that the twisting ring is always subjected to uniform torsional force during the twisting process, avoiding local undertwist or overtwist due to trajectory deviation.

The application discloses a kind of vision-based industrial robot intelligent discharging device, system and method, first discharging line is arranged in the discharge end of the transmission unit, including conveying unit, separating mechanism, visual detection mechanism and pushing mechanism;Conveying unit is arranged in the discharge end of the transmission unit, for conveying material;Separating mechanism is arranged in the first half of the conveying unit, for separating multiple materials;Visual detection mechanism is arranged in the middle section of the conveying unit;Pushing mechanism is arranged in the tail end of the conveying unit, for pushing out the material that detection is not up to standard.The present application avoids missing detection and wrong detection, makes the detection result more accurate, improves product quality consistency, greatly improves detection and discharging efficiency, avoids channel blockage and jam caused by mixed conveying of different height materials, ensures smooth conveying, avoids fatigue error caused by long-time operation, has the beneficial effects of low manufacturing cost, simple operation and not easy to damage, etc.

The utility model discloses a kind of anti-winding cable bollards, with: base;Pile, bottom fixed mounting on base;Helical rib, the outer surface of pile is equipped with helical rib extending spirally, cable can be wound in the gap of helical rib;Cover, cover on the upper end of pile;Lock catch, set on the side of base, by physical isolation, avoid the overlapping and winding between each circle of cable, reduce the abrasion of cable, improve the life of cable.

The application discloses a kind of sodium iron silicate negative materials and preparation method thereof.The method uses phosphating by-product silicon slag as silicon source, uses iron salt and sodium salt as raw material, uses template agent and solvent as auxiliary, and obtains the irregular spherical particle sodium iron silicate negative material by sol-gel method combined with stepwise heating calcination process.The application realizes high-value utilization of phosphating solid waste, and the prepared material has stable structure and exhibits high reversible capacity and excellent cycle stability when used as sodium-ion battery negative material.The method is simple, green and environmentally friendly, and low in cost, suitable for industrial production.

This invention discloses a forming device and method for forming a hydrogen-barrier material layer on the inner wall of a hydrogen-resistant bend, belonging to the field of bend inner wall coating forming. It includes a shell, with a guide head fixed at one end and a connector at the rear. A guide wheel is connected to the outside of the guide head. Spray nozzles are evenly distributed on the shell near the guide head. The rear wheel is linked to a drive plate, achieving adaptive adjustment of "the greater the bend, the more coating," ensuring uniform coating at the bend. The trigger component uses pure mechanical linkage, requiring no sensors, resulting in a simple and reliable structure. In the switching structure, the nozzle groove and the sealing slide have the same stroke, enabling continuous linear adjustment of the coating amount, avoiding leakage and unevenness. The cover plate provides unidirectional control to prevent backflow and ensure stable spray pressure. The guide wheel and rear wheel fixing seat are retractable to adapt to different pipe diameters, and the guide head weight-reducing holes improve throughput. An even number of nozzles with the same spray range avoids coating overlap or blind spots.

The present invention discloses a high-precision imaging detector, including a frame, a display is arranged at the middle of the top of the frame, a workpiece storage box is arranged on one side of the display, a support frame is arranged on the other side of the display, and a CCD camera is arranged on the top of the support frame; a bottom plate is arranged below the CCD camera and at the top of the frame, a workpiece shaking and placing mechanism is arranged on the top of the bottom plate, and a residual water removal mechanism is arranged on one side of the workpiece shaking and placing mechanism; the present invention also discloses an application of a high-precision imaging detector in environmental detection. The present invention can detect a larger number of workpieces at one time, and does not need to clean the surface of the workpiece separately, and can detect in batches, greatly improving the detection speed and efficiency; at the same time, the accuracy of imaging detection can be improved by using the CCD camera.

The invention relates to the technical field of vehicle fault diagnosis, and discloses a wheel bolt looseness detection method and device, a vehicle and a medium, and the method comprises the steps: collecting an inertial measurement unit signal, a wheel speed signal and a steering wheel hand torque signal of the vehicle; determining target detection data based on the inertial measurement unit signal, the wheel speed signal and the steering wheel hand torque signal; detecting whether a wheel bolt of the vehicle is loosened by using the target detection data to obtain a detection result; and controlling the vehicle to execute corresponding actions based on the detection result. According to the method, the existing sensor of the vehicle is directly used for collecting the signals, then the signals are fused with the multi-dimensional vehicle running state signals, feature extraction and combination processing are combined to form target detection data, the target detection data are used for wheel bolt looseness detection, full-process automation from signal collection, data processing, state detection to vehicle control action execution is achieved, and the detection efficiency is improved. And the detection accuracy and the driving safety are improved, so that the vehicle fault diagnosis requirements of low cost, high real-time performance and easy deployment are met.

The utility model is suitable for photovoltaic technical field provides a kind of back contact solar cell, battery component and photovoltaic system, back contact solar cell includes: silicon chip, the back of silicon chip includes the first area and the second area of alternative interval arrangement;First doped layer being arranged at first area;With the first electrode of first doped layer connection;Second doped layer being arranged at second area;With the second electrode of second doped layer connection;At least part second doped layer has the leakage contact portion extending to first doped layer, first doped layer includes the first sub-doped layer of composite contact being formed with leakage contact portion, the second sub-doped layer of not being formed with composite contact of leakage contact portion, the width of at least one first sub-doped layer along first direction is greater than the width of second sub-doped layer along first direction.The back contact solar cell of the utility model can improve power generation, especially can improve power generation under weak light condition.

The invention provides a method for determining related substances in a vitamin B6 drug, which comprises the following steps: dissolving a vitamin B6 drug sample in a prefabricated solution in a dark environment, filtering, and diluting to a target concentration interval to obtain a sample solution; placing the blank solvent, the contrast solution and the sample solution in a chromatographic column, introducing the mobile phase A and the mobile phase B, and sequentially carrying out gradient elution to obtain a chromatogram; and identifying and separating impurity chromatographic peaks in the chromatogram, performing quantitative or semi-quantitative analysis on each impurity chromatographic peak, and calculating the content proportion of each impurity chromatographic peak relative to the main chromatographic peak of the vitamin B6. Through collaborative design of the sample pretreatment state, the gradient elution path and the peak interpretation mode, known impurities and unknown impurities in the vitamin B6 medicine are in a separable state before entering a chromatographic system, and are fully expanded in the chromatographic separation process, so that accurate identification and effective separation of various impurities are realized.

This utility model discloses a cigarette pack diversion and anti-jamming device for a cigarette packaging machine, including a main conveyor, a connecting conveyor, and a diversion conveyor. Two anti-jamming levers are provided between the main conveyor and the connecting conveyor. A fixed guide plate is provided on one side of the connecting conveyor, with one end of the fixed guide plate installed inside the main conveyor to guide the cigarette packs into the connecting conveyor. Both the main conveyor and the side wall of the fixed guide plate have clearance slots, located at the intersection of the main conveyor and the connecting conveyor. Anti-jamming levers are rotatably connected to the inner walls of both clearance slots. The two anti-jamming levers, through alternating rotation without contact, dynamically sort the cigarette packs entering the intersection, preventing them from overlapping and allowing the preceding cigarette packs to pass first, while the following cigarette packs are intercepted and pass slightly later.

The invention discloses a front panel assembly and a top air outlet type air conditioner outdoor unit, and belongs to the technical field of air conditioners. The air conditioner outdoor unit comprises a machine shell, a heat exchange fan, a compressor, an outdoor heat exchanger, an electric control box and a terminal strip. The air outlet side of the heat exchange fan faces the air outlet; the compressor is positioned below the heat exchange fan; the windward side of the outdoor heat exchanger faces the air inlet, and the leeward side of the outdoor heat exchanger faces the compressor; the electric control box is located on the lateral lower portion of the heat exchange fan and the lateral upper portion of the compressor. The terminal row is arranged outside the electric control box and is positioned below the electric control box; the machine shell comprises a frame structure, a first panel, a second panel, a third panel and a fourth panel. The first panel is arranged corresponding to the heat exchange fan, the second panel is arranged corresponding to the electric control box, the third panel is arranged corresponding to the compressor, and the fourth panel is arranged corresponding to the terminal strip; the first panel, the second panel, the third panel and the fourth panel are respectively mounted or dismounted on the frame structure from different directions, so that the panels are prevented from interfering with one another during mounting or dismounting.