443results about How to "Reduce running noise" patented technology

The invention discloses an air conditioning system and a control method thereof. The air conditioning system comprises an air conditioning outdoor unit; the air conditioning outdoor unit comprises a compressor, an outdoor heat exchanger and an outdoor fan; the outdoor fan is at least provided with a first working mode and a second working mode; and when the outdoor fan runs in the first working mode, a wind gear is higher than that when the outdoor fan runs in the second working mode. The control method comprises the following steps that S1, the air conditioning system is controlled to enter arefrigeration mode; S2, according to the outdoor environment temperature and / or preset hours, the outdoor fan is controlled to enter the first working mode or the second working mode. According to the control method of the air conditioning system, the air conditioning system can control the outdoor fan to enter the first working mode or the second working mode according to the outdoor environmenttemperature and / or the preset hours, and when the outdoor fan runs in the second working mode, the wind gear of the outdoor fan is lowered, so that the use reliability the air conditioning system cannot be affected, and the requirement of a user on comfortableness can be met.

The invention relates to the technical field of heat dissipation control, and discloses a heat dissipation fan multi-order filtering control method and device, and the method comprises the steps: collecting the operation parameters of a multi-fan heat dissipation system, and carrying out the construction of a dynamic state space model, and obtaining a system operation state equation and a temperature observation equation; inputting the system operation state equation and the temperature observation equation into an expectation maximization sliding window iteration extended Kalman filter to obtain a system state estimation value and a prediction error covariance matrix; performing three-stage series design on the cut-off frequency of the low-pass filter, the passband range of the band-pass filter and the coefficient of the adaptive filter to obtain a system multi-order filtering control model; based on a system multi-order filtering control model, an airflow coupling influence coefficient matrix among multiple fans is calculated, the total energy consumption, the noise level and the heat dissipation efficiency are subjected to optimization solution, a fan control optimization parameter set is obtained, the heat dissipation efficiency is guaranteed while the energy consumption is reduced, and dynamic balance among all control units is achieved.

The invention provides a ratchet clutch with a friction cam, which is mainly applied to the technical field of transmission, in particular to the technical field of ratchet clutches. The ratchet clutch with the friction cam comprises a pawl, a ratchet, a return spring, a pawl seat and the friction cam. Under the direct or indirect friction action of the pawl seat or the ratchet wheel, the friction cam can selectively rotate relative to the ratchet wheel or the pawl seat within a certain angle range. And under the direct or indirect action of the friction cam, the return spring and the pawl, the pawl seat and the ratchet wheel can be selectively separated and combined. Compared with the prior art, the ratchet clutch provided with the friction cam can reduce operation noise between the pawl and the ratchet wheel in the separated state.

The invention provides an up-down air outlet air conditioner and a control method thereof. The up-down air outlet air conditioner comprises a shell, a first air inlet, a first air outlet, a second air inlet and a second air outlet. The indoor heat exchanger is arranged in the shell and divides the space in the shell into an upper space and a lower space; the first air duct is arranged in the upper space and communicates with the second upper air opening; the second air duct is arranged in the lower space and communicates with the first lower air opening; the first cross-flow fan blade is arranged in the first air duct; the second cross-flow fan blade is arranged in the second air duct; the first upper air opening and the first air channel can communicate with the second air channel, and the second air channel and the second lower air opening can communicate with the first air channel. According to the up-and-down air outlet air conditioner and the control method thereof, the requirements that cold air is not directly blown during refrigeration and hot air falls to the ground quickly during heating can be met, and too large noise cannot be generated.

The utility model belongs to the technical field of air conditioners, and discloses an air outlet mesh enclosure and an outdoor unit panel, main ribs are additionally arranged, and the minimum width of the main ribs in the radial direction of a center plate is limited to be larger than the width of radiation ribs in the radial direction of the center plate, so that the structural strength of the air outlet mesh enclosure is enhanced; therefore, when the air outlet mesh enclosure is designed, the number of the annular ribs can be reduced, so that the density of grids of the grating is reduced, the air outlet resistance of the air outlet mesh enclosure is reduced, and the noise of the air outlet mesh enclosure is reduced. Meanwhile, the minimum width of the main ribs in the radial direction of the center plate is limited to be larger than the width of the radial ribs in the radial direction of the center plate, the structural strength of the whole air outlet mesh enclosure can be improved, and the identification degree of the air outlet mesh enclosure is improved. In addition, the radiation ribs and the main ribs extend in the radial direction of the center plate in an arc mode, so that the radiation ribs and the main ribs are matched with the arc in the blade rotating direction of the wind wheel, the wind resistance of the air outlet mesh enclosure is smaller, and the air outlet noise is lower.

The invention relates to the technical field of servers, and discloses a server and a data center, the server comprises a server case, a first heat dissipation assembly and a refrigeration sheet, the server case is internally provided with a front function module and a rear function module, and the front function module and the rear function module are sequentially arranged along a first direction; the first heat dissipation assembly is arranged in the server case and comprises first heat dissipation fins and a first fan module, and the first heat dissipation fins and the first fan module are sequentially arranged between the front function module and the rear function module in the first direction; the refrigeration sheet is arranged on the side wall, in the second direction, of the server case and comprises a cold end and a hot end, and the cold end abuts against the first cooling fin; the second direction is perpendicular to the first direction, an internal cold source is provided for the server, the temperature in a server case is effectively reduced, and a continuous and stable low-temperature environment is provided for a rear functional module; and the heat dissipation efficiency in the server case is improved.

The present invention discloses an integrated device of a motor and a planetary reducer and a manufacturing method thereof, and the technical scheme thereof includes: a casing, a motor assembly and a planetary reducer assembly, the casing is provided with mounting cavities for the motor assembly and the planetary reducer assembly respectively, the motor assembly and the planetary reducer assembly are matched in transmission, and a cooling structure is provided on the outer circle of the casing. The manufacturing method mainly processes the casing, the stator core is installed on the casing, the rear end cover of the motor is fixed on the casing, the rotor of the motor is first installed on the front end cover inside the motor, and then pressed into the stator, the sun gear of the planetary reducer is installed on the motor shaft, and the gear lubricating oil is added through the planetary gear oil filling port on the casing, and the coolant needs to be introduced into the casing during operation. The entire technical scheme has a compact structure, simple transmission, and convenient maintenance, and the system efficiency, rotation accuracy, position accuracy and service life are greatly improved, and the heat generation and operating noise are greatly reduced.

The invention provides a double worm and gear driver. The double worm and gear driver comprises a shell; the driving motor is arranged in the shell; the first worm transmission assembly is arranged in the shell and comprises a first worm and a first worm gear which are in transmission fit, and the first worm is connected with the output end of the driving motor; the transmission gear is arranged in the shell and is in transmission connection with the first worm gear; the second worm transmission assembly is arranged in the shell and comprises a second worm and a second worm gear which are in transmission fit, and the second worm is in transmission connection with the transmission gear; the output shaft is used for being connected with an external driving load and comprises a transmission end and an output end which are connected, the transmission end is arranged in the shell and connected with the second worm wheel, the output end penetrates through the shell to the outside, the transmission structure layout of the driver is optimized, and operation noise is reduced. The invention further provides an automobile driving control system comprising the double worm and gear driver.

The invention discloses an automatic water-cooled power supply host system with independent partitions, and belongs to the technical field of power electronics, and the system is characterized in that the system comprises a host body, the host body is internally provided with a partition shelf, and the partition shelf is internally provided with a cavity. Each cavity is provided with an independent cooling coil, when a heating element corresponding to a certain cavity works to generate heat, a liquid pump sucks cooling liquid from an inlet pipe, the cooling liquid is accurately distributed through a flow dividing pipe and a flow control structure and then enters the cooling coil of the cavity, and by means of the independent cooling mode, when one cavity breaks down, the cooling liquid can be cooled by the liquid pump. The cooling liquid circulation is only influenced in the loop of the cavity, other cavities can still work normally, the reliability of the system is greatly improved, the overall downtime caused by local faults is shortened, and meanwhile, due to the design of the independent cavities, workers can quickly position fault points conveniently, and only the fault cavity is maintained and repaired.

The invention relates to a mesh enclosure and a fan, and the mesh enclosure comprises a first air supply assembly which comprises at least two air supply grilles, and the air supply grilles are connected into a whole in the circumferential direction of the mesh enclosure; wherein each air supply grille is provided with an air supply main body and at least two first ribs, the first ends of all the first ribs are gathered together and connected to the air supply main body, and the second ends of all the first ribs are arranged at intervals in the circumferential direction of the mesh enclosure; the air supply body is provided with first air guide channels, and a second air guide channel is formed between every two adjacent first ribs. The fan comprises the mesh enclosure. The fan, the first air guide channel and the second air guide channels are sequentially arranged in the radial direction of the mesh enclosure, the second air guide channels are distributed along the mesh enclosure in a scattered mode from the gathering point, airflow distribution is enhanced in the circumferential direction and the radial direction of the mesh enclosure, multi-path airflow flowing is achieved, and wind resistance and operation noise are effectively reduced.

The utility model belongs to the technical field of online transmission of new energy automobile battery packs, and discloses a heavy-load friction power and free roller way suitable for battery pack assembly, which comprises a conveying unit with a roller way, the conveying unit is provided with an open slot, and a roller combination is mounted in the open slot; the power and free transmission shaft is sleeved with the power and free unit, and the power and free unit is meshed with the roller combination to control starting and stopping of the roller combination. By arranging the power and free unit, when the load torque is larger than the friction torque, the power and free unit enables the roller combination to stop moving, at the moment, the power and free function is achieved, friction between the roller combination and the friction face of the tray where the battery pack is placed is reduced, and therefore the service life of the conveying equipment is prolonged.

The invention discloses a hydrothermal management system and method and a fuel cell system. The hydrothermal management system is used for heat management of a fuel cell system, and the hydrothermal management system comprises a solid hydrogen storage module configured as a hydrogen supply source of the fuel cell system so as to be capable of absorbing heat and releasing hydrogen; the phase change heat storage module is configured to be capable of storing part of heat generated by operation of the fuel cell system; and the hydrothermal circulation loop is configured to be capable of transferring heat generated by operation of the fuel cell system to the solid hydrogen storage module and the phase change heat storage module, and transferring heat stored by the phase change heat storage module to the solid hydrogen storage module. According to the hydrothermal management system provided by the invention, the heat dissipation cost can be reduced, the heat dissipation power and the operation noise are reduced, and the heat utilization rate is improved.

The invention relates to the technical field of food processing, in particular to a holographic display system based on artificial intelligence, which comprises a display module, an artificial intelligence control module, a safety protection module and a noise reduction module, the display module comprises a plane holographic unit and a three-dimensional holographic unit, and the three-dimensional holographic unit is arranged in the plane holographic unit; the artificial intelligence control module enables the projection of the transmission image of the plane holographic unit and the projection of the three-dimensional image in the three-dimensional holographic unit on the plane where the plane holographic unit is located to be completely overlapped through a deep learning algorithm. According to the holographic display system, the display module, the artificial intelligence control module, the safety protection module and the noise reduction module are arranged, so that the intelligence and the safety of the holographic display system are realized. And the plane holographic unit and the three-dimensional holographic unit of the display module are combined, so that the image display is more three-dimensional and vivid. And the artificial intelligence control module ensures accurate superposition of the images through a deep learning algorithm, so that the accuracy and reality of the display effect are improved.

The invention provides a stator core, a plastic package stator assembly, a manufacturing method of the plastic package stator assembly, a motor and an air conditioner, the stator core comprises two semi-circular iron core section split bodies, and the two semi-circular iron core section split bodies are respectively provided with assembling surfaces which are attached to each other to form a whole circle. The assembling surfaces of the two semicircular iron core section split bodies are spliced through a transverse sliding limiting structure, the transverse sliding limiting structure is located in the middle area of the axial length of each semicircular iron core section split body, and the sliding insertion direction of the transverse sliding limiting structure is the first diameter direction of the stator iron core. According to the stator assembly, more reliable limiting in the axial direction and the radial direction can be achieved after the two semicircular iron core sections are spliced in a split mode, then radial dislocation and deviation of the stator iron core due to impact of injection molding materials in the subsequent plastic packaging process can be prevented, the concentricity of the stator assembly is improved, and operation noise of a motor can be lowered.

The invention discloses a high heat dissipation type direct current permanent magnet synchronous servo motor and a using method, and relates to the technical field of motors, the high heat dissipation type direct current permanent magnet synchronous servo motor comprises a center shaft and a stator, a rotor is arranged in the middle of the outer surface of the center shaft, the stator sleeves the rotor, and a sealing cover is arranged on one side of the outer surface of the center shaft. As the temperature of the electric brush assembly rises, the thermal expansion coefficient of the material can cause slight deformation or position adjustment of the electric brush, and the change can help maintain good contact pressure between the electric brush and the commutation copper sheet, so that contact resistance increase caused by temperature rise is reduced; graphite powder generated by abrasion of an electric brush can form a layer of conductive film on the surface of the commutation copper sheet, although the graphite is a conductor, if the graphite is not uniformly distributed, poor local contact is caused, and proper temperature control and design can ensure that the graphite layer is more uniformly distributed on the commutation copper sheet, and on the contrary, the electric contact quality can be improved.

The invention relates to the artificial intelligence technology, and discloses a regulation and control method and device for cooling fans in a relatively closed space and a cooling system.The regulation and control method comprises the steps that electronic devices in the relatively closed space are controlled to operate in different power consumption modes, and a plurality of cooling fans are controlled to operate in cooperation with parameter combinations of different rotating speeds and rotating directions; temperature data of the electronic device and wind noise data outside the relatively closed space are collected; inputting related collected data into the artificial intelligence model for training, and generating corresponding optimal parameter combinations between the cooling fans when the electronic device is in different power consumption modes; and when the electronic device is actually applied, cooling the electronic device by using the corresponding optimal parameter combination between the cooling fans according to the current power consumption mode of the electronic device. The invention further discloses a computer readable storage medium. The invention aims to reduce the generated wind noise as much as possible while cooling the electronic device in the relatively closed space by using the cooling fan.

The utility model provides a planet carrier limiting structure of a multi-stage planetary transmission device, which comprises a gear box body, a motor output shaft and a gear box output shaft are arranged in the gear box body, and the motor output shaft is connected with the gear box output shaft through a planet carrier; a concentric structure; the concentric structure comprises a close-fitting opening formed in the planet carrier, a first loose-fitting opening is formed in the side wall, close to the planet carrier, of the output shaft of the motor, a second loose-fitting opening is formed in the side wall, close to the planet carrier, of the output shaft of the gearbox, and the close-fitting opening is concentrically matched with the first loose-fitting opening and the second loose-fitting opening. And a fixing rod is arranged in the close-fitting opening, the first loose-fitting opening and the second loose-fitting opening. According to the utility model, the stable operation of concentric rotation can be ensured, the radial vibration problem is avoided, and the operation noise is reduced.

The invention provides a rotor structure and a motor. The rotor structure comprises a rotor core (2), the rotor core (2) is provided with filling grooves (4) and permanent magnet grooves (5), permanent magnets (6) are installed in the permanent magnet grooves (5), the filling grooves (4) are distributed on the periphery of the rotor core (2), the filling grooves (4) comprise q-axis filling grooves (42) and d-axis filling grooves (41), the q-axis filling grooves (42) comprise connecting filling grooves (43) and independent filling grooves (44), and the d-axis filling grooves (41) comprise connecting filling grooves (43) and independent filling grooves (44). The connecting filling grooves (43) and the permanent magnet grooves (5) are arranged on the same layer and are arranged at the two ends of the permanent magnet grooves (5), the independent filling grooves (44) are located between the adjacent connecting filling grooves (43), and the distances between the independent filling grooves (44) and the connecting filling grooves (43) on the two adjacent sides are different. According to the rotor structure, the efficiency of the motor can be improved, and the performance of the motor is improved.

The invention discloses an engineering machinery split electro-hydrostatic actuator and a control method thereof. The split electro-hydrostatic actuator for the engineering machinery comprises an integrated power source assembly and actuator units configured remotely, wherein hydraulic pressure generated by the integrated power source assembly is supplied to the actuator units such as a hydraulic cylinder through a flexible hydraulic pipeline. In addition, the controller can control the motor to work according to working parameters fed back by the sensor assembly through a multi-loop control method. The split type layout design is combined with a multi-loop control method, and an operation system which is good in dynamic performance, high in response speed, low in operation noise and good in heat dissipation performance is achieved.

The invention discloses a walking transmission mechanism, a walking device and a three-dimensional storage robot, the walking transmission mechanism comprises a box body and a gear set arranged in the box body, and the gear set comprises a primary rail transmission gear set, a reversing gear set and a secondary rail transmission gear set; the mother rail transmission gear set comprises a driving mother rail gear and a driven mother rail gear which are meshed with each other, the driving mother rail gear serves as a walking power input end, and the driven mother rail gear serves as a first walking power output end; the reversing gear set comprises a reversing output shaft, a reversing input bevel gear and a reversing output bevel gear, the reversing input bevel gear and the reversing output bevel gear are meshed with each other, the reversing input bevel gear is arranged on one side of the driven mother rail gear and keeps static relative to the driven mother rail gear, and the reversing output shaft is connected with the reversing output bevel gear. The sub-rail transmission gear set comprises a driving sub-rail gear and a driven sub-rail gear which are meshed with each other, the driving sub-rail gear is connected with the reversing output shaft, and the driven sub-rail gear is a second walking power output end. According to the invention, the secondary rail transmission shaft and the primary rail transmission shaft can be prevented from being vertically crossed.

The utility model discloses a manual and electric dual-purpose bean grinder which comprises a grinding mechanism, a manual driving mechanism and an electric driving mechanism, wherein the manual driving mechanism can be matched with the grinding mechanism for use; the electric driving mechanism can be matched with the grinding mechanism for use; the manual and electric dual-purpose bean grinder comprises a grinding mechanism, a manual driving mechanism and an electric driving mechanism, the manual driving mechanism can be matched with the grinding mechanism for use, the electric driving mechanism can be matched with the grinding mechanism for use, and when the grinding mechanism is matched with the manual driving mechanism for use, the manual and electric dual-purpose bean grinder can be used as a manual bean grinder; when the grinding mechanism is matched with the electric driving mechanism for use, the grinding mechanism can be used as the electric driving mechanism; meanwhile, compared with a manual bean grinder and an electric bean grinder which are manufactured at the same time, the manufacturing cost is lower.

The invention discloses a quantitative visual detection device for underwater fishery resources, and relates to the technical field of fishery resource detection, the inner side of an elliptical hard sleeve is fixedly connected with an internal load-bearing frame, the inner side of the internal load-bearing frame is embedded and clamped with a fixed battery, and one end of the internal load-bearing frame is embedded with a control recorder; supporting alignment plates are symmetrically welded to one end of the oval hard sleeve, limiting springs are symmetrically installed at one ends of the supporting alignment plates, a closed waterproof sleeve is installed between the two limiting springs, through mutual cooperation of a plurality of components, switching of different operation modes of equipment in the moving process and the detection process is achieved, and the problem that in the prior art, the detection efficiency is high is effectively solved. The invention aims to solve the problem of inaccurate detection caused by the influence of high noise on animals, reduces the influence of impurities on equipment operation by utilizing multiple groups of protection operations and self-separation operations, improves the stability and safety of equipment operation, and improves the detection range and the detection accuracy by matching with multi-angle and multi-position detection.

The invention provides an oil baffle cap, a compressor and an assembly method of the compressor, and belongs to the technical field of compressors, the oil baffle cap comprises a cap body, the cap body is fixed on one side of a rotor of the compressor, a connecting cylinder is arranged in the cap body, a connecting hole is formed in the connecting cylinder, and the diameter of the connecting hole is larger than the outer diameter of a crankshaft of the compressor. N welding grooves are formed in the connecting cylinder and are welded and fixed with a crankshaft of the compressor, so that the oil baffle cap is fixed on the crankshaft of the compressor; n is a natural number greater than 1. The oil baffle cap can be welded and fixed with the crankshaft of the compressor through the welding groove, and the crankshaft does not need to be in interference fit with a shaft hole of a rotor in the assembling process, so that deformation of a rotor iron core can be effectively reduced, noise during operation of the compressor is reduced, and vibration of the compressor is reduced.

The invention relates to an epoxy resin pouring type transformer with built-in microcirculation cooling channels and a heat dissipation method of the epoxy resin pouring type transformer, and belongs to the technical field of power transformers. The epoxy resin pouring type transformer comprises an iron core, a low-voltage winding, a high-voltage winding and a heat dissipation shell, the low-voltage winding and the high-voltage winding are completely impregnated and wrapped by an epoxy resin composite material through a vacuum pouring process, an integrated epoxy resin pouring body is formed after curing, and a three-dimensional communicated bionic microcirculation cooling channel network is arranged in the epoxy resin pouring body; the heat dissipation shell is in close contact with the outer surface of the epoxy resin pouring body through the high-heat-conductivity insulating medium. According to the invention, the heat dissipation efficiency can be remarkably improved, and a cooling medium (air) is directly guided to a microscopic area around the winding conductor through a three-dimensional communicated and tree-shaped fractal bionic microcirculation cooling channel network, so that the effective heat exchange area and the heat exchange strength are greatly increased, and internal heat can be accurately and efficiently taken away.

The invention discloses a silencing device for an outlet of a fire-fighting smoke exhaust fan. The silencing device comprises a mounting cylinder and a plurality of components assembled in the mounting cylinder, wherein the components comprise a smoke dust cleaning component, a heat exchange silencing component, a smoke dust collecting tank, an adsorption component and a smoke dust discharging component. The smoke cleaning assembly is located at the top of the mounting cylinder, the heat exchange silencing assembly and the smoke collecting tank are connected to the bottom of the mounting cylinder, the adsorption assembly is connected to the bottom of the heat exchange silencing assembly, and the smoke discharging assembly is connected to the bottom of the smoke collecting tank and located on the inner side of the adsorption assembly. The device forms a closed cold air through cavity, and a smoke outlet is formed in the bottom, so that effective smoke emission is ensured. In addition, the device further comprises a stirring assembly, a conveying assembly and a driving assembly which are connected with the adsorption assembly and the smoke dust discharging assembly respectively. Not only is the silencing effect remarkably improved, but also the functions of smoke cooling, dust removal and toxic and harmful substance treatment are integrated, many problems in the prior art are effectively solved, and a safe, environment-friendly and efficient smoke exhaust silencing device is provided for the field of fire protection and smoke exhaust.

The utility model provides an adjustable-speed motor, a fixed-frequency compressor and refrigeration equipment. The adjustable-speed motor comprises a stator assembly. The stator assembly includes a stator winding and a stator core. The stator winding comprises a first winding and a second winding arranged in parallel with the first winding. The stator core body is provided with a first center hole used for installing the rotor assembly and a plurality of wire embedding grooves, the sizes of the wire embedding grooves are uniform, and the first winding and the second winding are arranged in the wire embedding grooves in a stacked mode. The adjustable-speed motor has a first speed and a second speed smaller than the first speed. In the first speed state, at least parts of coils in the first winding and the second winding are arranged in parallel. And in the second speed state, the coils in the first winding and the second winding are respectively connected in series. The adjustable-speed motor provided by the utility model can drive the fixed-frequency compressor to operate at different rotating speeds under the high-load working condition and the low-load working condition, so that the energy consumption and the operation noise of the refrigeration equipment under the low-load working condition are reduced, and the user satisfaction is improved.

The utility model relates to the technical field of breathing machine fans, in particular to a fan volute structure for a breathing machine. The volute structure comprises an outer shell, a driving mechanism and a control part, the outer shell comprises an upper shell body and a lower shell body which are in butt joint, an air inlet is formed in the upper shell body, the upper shell body and the lower shell body are in butt joint, an air outlet is formed in one end of the outer shell body, an air cavity for communicating the air inlet and the air outlet is formed in the outer shell body, and the upper shell body is arranged in a concentric circle; the lower shell is not arranged in a concentric circle; the driving mechanism comprises a motor shell, a driving assembly, a fan blade piece and a first lower end cover, one end of the motor shell penetrates through the lower shell, the driving assembly is located in the motor shell, the rotating shaft is exposed out of the motor shell and connected with the fan blade piece, the fan blade piece is located in the air cavity, and the first lower end cover abuts against the motor shell and is connected with the lower shell; the control piece is contained in the first lower end cover, electrically connected with the driving assembly and externally connected with a power source. Efficient airflow conduction can be achieved, and the noise of the fan can be reduced.

The utility model relates to a kind of simple structure temperature-control accurate cold water machine system, solve the problem of the complex structure of current cold water machine, large outlet water temperature fluctuation. Including with cold equipment, cold water machine system further include plate heat exchanger, filter, backwater temperature sensor, outlet water temperature sensor and mixing device, plate heat exchanger is equipped with plate heat exchanger hot side water inlet, plate heat exchanger hot side water outlet, plate heat exchanger cold side water inlet, plate heat exchanger cold side water outlet. The utility model exchanges heat with external cooling water source using plate heat exchanger;And by setting tee valve on backwater pipe, according to system actual load (such as backwater temperature or outlet water temperature) dynamic adjustment the proportion of cooling water quantity and bypass water quantity that flow through plate heat exchanger, realize accurate, continuous and smooth control to outlet water temperature. In addition simple structure, energy consumption is low, compressor operation noise is small, especially suitable for the occasion of high temperature control precision requirement, need energy saving and emission reduction.

The protective cover comprises an outer plate and an inner plate, the outer plate is in threaded connection with a threaded rod along a center shaft, the inward end of the threaded rod is coaxially connected with a rotating seat, the inward end of the rotating seat is rotatably connected with a rotating rod, the inward end of the rotating rod is coaxially connected with the inner plate, and the inward face of the inner plate is provided with a sound insulation layer. An elastic cushion is arranged on the inward face of the sound insulation layer, a protective net is connected to the outer edge of the outer plate, the center of the protective net coincides with the center of the outer plate, and connecting assemblies are evenly arranged on the edge of the outward face of the protective net. In the ventilator, the inner plate is sealed in a concave position in the middle of a hub, the elastic cushion abuts against the hub, the hub is connected with a driving rod of a motor, and the hub is driven by the motor to rotate. A rotating shaft of the hub and a rotating shaft of the inner plate are located on the same straight line, the protective net covers the outer sides of the blades connected with the hub, and the connecting assembly is detachably connected with the inner wall of the cavity where the hub is located. The utility model has the advantages that the noise can be reduced, and the safety is improved.

The utility model relates to a matching structure of an inner knife and an outer knife of a biopsy needle. The matching structure comprises an inner knife tube and an outer needle tube sleeved outside the inner knife tube, an expansion pipe section capable of containing more collected tissues is arranged on the front side of the inner knife pipe, and the lower peripheral side pipe wall, corresponding to the pipe section, of the tissue suction inlet expands outwards to form an expansion groove structure; a fluid conveying channel is formed between the expansion groove structure and the outer wall of the expansion pipe section; the rear section of the inner knife tube is in clearance fit with the rear section of the outer needle tube to form an annular conveying cavity communicated with the fluid conveying channel. According to the utility model, the expansion tube section of the inner knife tube is matched with the expansion groove structure of the outer needle tube, so that the sample collection space of the inner knife tube is maximized, and the sampling effect is improved; while the outer wall surface of the expansion tube section is tightly attached to the inner wall surface of the outer needle tube, the gap is minimized, meanwhile, the expansion groove structure of the outer needle tube can be communicated with the annular conveying cavity, fluid communication is ensured, and cutter blockage caused by the fact that fluid cannot be communicated after tissue cutting is completed is avoided.