An electric energy metering box with adjustable heat dissipation module

Abstract

The application discloses an electric energy metering box with an adjustable heat dissipation module, which comprises a box body, a heat dissipation window is formed in the wall plate of the box body, and a heat dissipation module is assembled at the heat dissipation window. The heat dissipation module comprises a first perforated grid plate and a second perforated grid plate which are sequentially stacked along the normal direction of the wall plate. The first perforated grid plate and the second perforated grid plate are both provided with regularly arranged through holes. A guide slide rail is arranged in the box body, the first perforated grid plate is assembled on the guide slide rail, and the second perforated grid plate is fixed in the box body. One end of the first perforated grid plate is fixedly connected with the wall plate through a driving mechanism, and the other end is fixedly connected with the inner wall of the accommodating space of the wall plate through a reset tension spring. A dehumidification prechamber and an electrical core room are further arranged in the box body. The dehumidification prechamber is located between the heat dissipation module and the electrical core room. The first perforated grid plate and the second perforated grid plate are stacked along the normal direction of the wall plate at the position of the side wall of the box body, and the two layers of grid plates can slide relative to each other to realize on-off switching of the ventilation channel.

Description

Technical Field

[0001] This invention relates to the field of electricity metering box technology, specifically to an electricity metering box with an adjustable heat dissipation module. Background Technology

[0002] With the continuous advancement of smart grid and ubiquitous power Internet of Things construction, the types of integrated devices inside outdoor power metering boxes are becoming increasingly diverse. These boxes simultaneously house high-precision metering chips, wireless communication modules, multi-channel input / output terminals, and edge acquisition units. During long-term operation, these devices continuously generate heat. Under conditions such as summer outdoor exposure and peak electricity load, the heat inside the box cannot dissipate quickly enough, easily causing the internal temperature to rise continuously. Once the temperature exceeds the rated operating range of the devices, the sampling accuracy of the metering chip will drift, the signal transmission and reception stability of the communication module will decrease, and high-power terminals may experience oxidation and increased contact resistance due to heat accumulation, shortening the service life of the entire metering system. To improve heat dissipation inside the cabinet, most existing power metering boxes have ventilation structures on the side walls, relying on air convection to exchange heat. The most common ventilation structures on the market fall into two categories: one is a fixed-angle louver structure, where the louvers are integrally formed with the side wall of the cabinet. The size of the ventilation opening cannot be adjusted according to the real-time temperature inside the cabinet. In low-temperature environments, the ventilation channel remains open, allowing external moisture and dust to continuously enter the cabinet. In high-temperature conditions, the fixed ventilation area is difficult to match the significantly increased heat generation demand. The other type is an electrically driven tilting louver structure. Temperature sensors and control circuit boards are installed inside the cabinet. When the temperature reaches a set value, the controller drives the motor to tilt the louvers, opening the ventilation channel. After the temperature drops, the louvers close.

[0003] When the ventilation channels of the two types of ventilation structures mentioned above are fully open, large, continuous holes will form on the side walls of the enclosure. The horizontal and vertical dimensions of these holes are much larger than half the wavelength of electromagnetic waves emitted by surrounding base stations and wireless radio frequency equipment. External high-frequency electromagnetic radiation can directly penetrate through the ventilation holes and enter the enclosure. The weak sampling circuit of the high-precision metering chip is highly susceptible to electromagnetic interference, resulting in deviations in the measurement values. The signal transmission link of the wireless communication module will also experience noise interference, leading to frequent data packet loss and communication interruptions. Some solutions in the industry use metal shielding mesh at the ventilation openings to weaken electromagnetic interference. While the metal mesh can slightly reduce the penetration intensity of electromagnetic waves, electromagnetic leakage channels still exist in the mesh openings. Furthermore, the metal mesh significantly increases airflow resistance and reduces the enclosure's convective heat dissipation efficiency, failing to simultaneously meet the requirements for both heat dissipation and electromagnetic shielding.

[0004] Outdoor electricity metering boxes are exposed to the natural environment for extended periods. Diurnal temperature variations, high humidity during the rainy season, and salt spray from coastal areas all contribute to air convection, drawing moisture into the box. Existing ventilation systems lack proper moisture separation mechanisms, allowing moisture-laden air to directly contact the internal metal components and circuit boards. Upon cooling, this moisture condenses on metal grilles, slide rails, and component surfaces. Prolonged contact with this condensation causes gradual corrosion of metal components. The oxide layer at sliding joints increases sliding resistance, making ventilation systems prone to jamming and preventing proper opening and closing. Once an insulating oxide layer forms on the metal contact surfaces, the box's complete electromagnetic shielding circuit breaks, leading to significant electromagnetic wave leakage. Condensation on circuit board surfaces degrades insulation, causing leakage and short circuits. Corrosion of metal terminals reduces contact stability, further exacerbating localized heat generation and creating a vicious cycle.

[0005] To address this, an energy metering box with an adjustable heat dissipation module is proposed. Summary of the Invention

[0006] One of the technical problems that this application aims to solve is that the existing adjustable ventilation structure of the power metering box is difficult to balance efficient heat dissipation and high-frequency electromagnetic shielding. It also suffers from multiple defects, such as easy jamming of the transmission, magnetic leakage due to the sliding edge of the grid plate, unstable shielding effectiveness of the through-hole array, ineffective separation of air intake water vapor which easily leads to condensation and corrosion of components, poor water vapor separation and drainage effect of the dehumidification structure, and insufficient guide limit and friction reduction conductivity of the slide rail.

[0007] To solve the above-mentioned technical problems, this application provides an energy metering box with an adjustable heat dissipation module, including a box body. A heat dissipation window is opened on the wall panel of the box body, and a heat dissipation module is installed at the heat dissipation window. The heat dissipation module includes a first perforated grid plate and a second perforated grid plate stacked sequentially along the normal direction of the wall panel. Both the first perforated grid plate and the second perforated grid plate have regularly arranged through holes. A guide slide rail is provided inside the box body. The first perforated grid plate is installed on the guide slide rail, and the second perforated grid plate is fixed inside the box body. One end of the first perforated grid plate is fixedly connected to the wall panel through a drive mechanism, and the other end is fixedly connected to the inner wall of the receiving space of the wall panel through a reset spring. The enclosure also includes a dehumidification pre-compartment and an electrical core compartment. The dehumidification pre-compartment is located between the heat dissipation module and the electrical core compartment, and it is equipped with a drain outlet.

[0008] In some embodiments, the driving mechanism is a temperature driving element, which is a shape memory alloy spring, and the preload of the reset spring is much smaller than the high-temperature elongation thrust of the shape memory alloy spring.

[0009] In some embodiments, the through hole includes a straight cylindrical section and flared sections located at both ends of the straight cylindrical section, wherein the diameter of the flared sections gradually increases in the direction away from the straight cylindrical section; The through holes on the first perforated grid plate and the second perforated grid plate are arranged in a multi-row array. The through hole array alternates between first-specification holes and second-specification holes along the row direction. The first-specification holes are arranged in odd-numbered rows and the second-specification holes are arranged in even-numbered rows. The diameter of the first-specification hole is the maximum allowable through hole diameter calculated according to the electromagnetic shielding cutoff hole diameter formula, and the diameter of the second-specification hole is smaller than the diameter of the first-specification hole. The first and second specification holes are staggered along the plane of the plate. When the first perforated grid plate moves relative to the second perforated grid plate, the first and second specification holes can form a multi-level overlapping and interconnected ventilation channel.

[0010] In some embodiments, a dovetail groove is provided on the guide rail, and a dovetail slider matching the dovetail groove is provided at the bottom of the first perforated grid plate. The dovetail slider is embedded in the dovetail groove and slides along the extension direction of the dovetail groove. Several recessed grooves are provided on the inclined surface of the dovetail groove. A ball bearing is fixed in the recessed groove by several rotating shafts. A second recessed groove is provided on the inclined surface of the dovetail slider that contacts the dovetail groove. The size of the second recessed groove matches that of the ball bearing. When the dovetail slider slides along the extension direction of the dovetail groove, the ball bearing set in the first recessed groove rolls around the rotating shaft.

[0011] In some embodiments, the dehumidification pre-filter is provided with multiple sequentially connected baffle channels, and the flow cross-sectional areas of adjacent baffle channels are different.

[0012] In some embodiments, the windward sidewall of the baffle channel is provided with a hydrophilic coating area, and the leeward sidewall of the baffle channel is provided with a superhydrophobic coating area.

[0013] In some embodiments, a flow guide channel is provided at the bottom of the dehumidification pre-compartment, and a flow guide protrusion is provided on the flow guide channel. One end of the flow guide channel is connected to the drain outlet, and the drain outlet penetrates through the wall panel of the housing.

[0014] In some embodiments, the heat dissipation module further includes a third perforated grid plate, which is disposed on the side of the second perforated grid plate away from the first perforated grid plate and is connected to the second perforated grid plate via a guide rail. The third perforated grid plate has through holes distributed on it, and the structure of the third perforated grid plate is the same as that of the first perforated grid plate. Under the drive of the drive mechanism, the through holes on the third perforated grid plate are aligned and connected with the through holes on the second perforated grid plate.

[0015] In some embodiments, in the initial state, the through holes on the first perforated grid plate and the second perforated grid plate are staggered. When the temperature is high, the drive mechanism extends and drives the first perforated grid plate to move relative to the second perforated grid plate along the guide slide rail, so that the through holes on the two are aligned and connected, forming a ventilation channel array that runs through the wall panel along the normal direction and the channel depth is greater than the hole diameter.

[0016] In some embodiments, the interior of the dehumidification pre-pack is provided with several sets of guide plates 1, 2, and 3 that gradually slope towards the heat dissipation module, facilitating the flow of droplets along the guide plates 1, 2, and 3 towards the drain outlet. The guide plates 1, 2, and 3 are connected in sequence, and the tail end of the guide plate 3 is provided with a guide ridge to guide the droplets to the drain outlet. The top and bottom surfaces of the guide plates 1, 2, and 3 are provided with several evenly distributed guide ridges 2 to facilitate droplet guidance. The uppermost guide plates 1, 2, and 3 are provided with moisture-absorbing material to assist in moisture absorption.

[0017] The present invention has at least the following beneficial effects: 1. By installing a first perforated grid and a second perforated grid stacked along the normal direction of the wall panel on the side wall of the enclosure, the two layers of grids can slide relative to each other to switch the ventilation channel on and off. After the through holes are aligned, they form a long and narrow channel array with a depth greater than the aperture. Air can smoothly pass through the channels to complete the convection heat exchange between the inside and outside of the enclosure. High-frequency electromagnetic waves are exponentially attenuated inside the long and narrow channels, and electromagnetic radiation generated by external radio frequency and base stations is difficult to penetrate the enclosure, so it will not interfere with the stable operation of the internal metering chip and communication module. When the ventilation channel is open, the enclosure can still maintain complete electromagnetic shielding performance, avoiding deviations in metering values ​​and loss of communication data. In the initial state, the through holes of the grid are misaligned. When the temperature inside the enclosure is low, the ventilation channel is completely closed, making it difficult for external dust and moisture to enter the enclosure, reducing the probability of contamination and corrosion of components. The added third perforated grid can further increase the overall depth of the electromagnetic wave attenuation channel, improve the shielding attenuation in usage scenarios with higher electromagnetic interference intensity, and broaden the range of outdoor environments suitable for the equipment.

[0018] 2. A shape memory alloy drive mechanism is arranged parallel to the guide rail at the end of the first perforated grid plate. The power transmission direction is consistent with the sliding direction of the grid plate, simplifying the power transmission path and eliminating cam-related components. No force perpendicular to the grid plate surface is generated during the transmission process, ensuring a tight fit between the two grid plates throughout the sliding process and preventing local warping and separation that could create leakage gaps. A reset spring works in conjunction with the shape memory alloy spring. At high temperatures, the shape memory alloy elongates to overcome the spring's tension, pushing the grid plate to slide and open the window. As the temperature decreases, the spring assists in resetting the grid plate. Even at low temperatures, the grid plate can achieve complete misalignment and sealing of the through holes, preventing residual gaps in the ventilation channel from causing continuous electromagnetic leakage. The entire drive structure requires no external power supply or control circuit board, relying on the material's own temperature deformation for automatic adjustment, reducing the possibility of electrical faults and improving the stability of long-term outdoor operation.

[0019] 3. The guide rail, combined with dovetail grooves and dovetail sliders, completes the sliding limit of the grid plate, synchronously constraining the movement trajectory of the grid plate on both the upper and lower sides. The grid plate will not deviate or tilt during sliding. A recessed groove is formed on the inclined surface of the dovetail groove to install ball bearings, and a corresponding recessed groove is provided on the dovetail slider to accommodate the ball bearings. When the grid plate moves, the ball bearings roll around the axis, transforming the original sliding friction of direct metal-to-metal contact into rolling friction. This significantly reduces sliding resistance, and dust entering the mating gap is less likely to cause sliding jamming. The ball bearings continuously contact the metal contact surfaces of the slider and the guide rail, maintaining equipotential conductivity between the two grid plates during sliding. No electrical breaks occur in the shielding cavity, ensuring the continuity and integrity of the overall shielding circuit of the enclosure and reducing the probability of electromagnetic wave leakage from the sliding mating position.

[0020] 4. The grid panel features alternating through-holes of two sizes. Odd-numbered rows contain larger first-size holes, while even-numbered rows contain smaller second-size holes. The larger through-holes ensure sufficient overall ventilation area to meet heat dissipation requirements under high-temperature conditions. Adjacent smaller through-holes provide stronger attenuation for high-frequency electromagnetic waves. External electromagnetic waves passing through the large-diameter channels are blocked and reflected by the metal ribs corresponding to the smaller holes, further weakening their penetration. The alternating arrangement of large and small holes breaks the periodic structure of the through-hole array, preventing resonance caused by electromagnetic waves of specific frequencies passing through the array and thus reducing shielding effectiveness. The staggered arrangement of different hole sizes along the panel allows for multi-level gradual adjustment of the ventilation area during relative sliding of the grid panel. This ensures a smooth change in ventilation volume when the internal temperature changes, preventing drastic temperature fluctuations. The staggered arrangement of different sized through-holes also widens the local metal ribs of the grid panel, improving the planar structural rigidity of the entire perforated grid panel. This prevents deformation and warping of the grid panel after long-term reciprocating sliding, maintaining the continuous fit between the two grid layers. The through-hole is equipped with a straight cylindrical section and flared sections at both ends. The straight cylindrical section maintains the aperture size required for waveguide attenuation, while the flared structure at both ends reduces the flow resistance of air entering and exiting the channel. Under the same ventilation area, the air convection efficiency is improved. When the airflow enters and exits the channel, it is less likely to form eddy current loss at the orifice. During the sliding alignment of the grid plate, the flared section can also play a guiding and buffering role, reducing the situation of the orifice edges scraping and getting stuck.

[0021] 5. An independent dehumidification pre-compartment is set up between the heat dissipation module and the electrical core compartment. After entering the enclosure, the outside air first flows through the dehumidification pre-compartment before contacting various electrical components. The flow cross-section of multiple baffle channels inside the compartment changes alternately. When the airflow passes through the cross-sectional expansion area, the flow velocity decreases and the temperature drops, and the water mist carried in the air is initially precipitated. The hydrophilic coating on the windward side of the baffle channel can adsorb the fine water vapor in the airflow to form a continuous water film, and the superhydrophobic coating on the leeward side can accelerate the water film to converge into water droplets, reducing the possibility of fine water mist entering the component area with the airflow. The dehumidification pre-compartment is arranged with multiple layers of sequentially connected guide plates. The guide plates are inclined towards the heat dissipation module, and the surface of the plates is evenly provided with guide strips. The precipitated liquid water droplets can quickly converge along the strips and the plate surface. The guide ridges at the end of the guide plates guide all the accumulated water to the bottom guide channel. The guide strips inside the guide channel further accelerate the flow speed of the accumulated water. The accumulated water is finally discharged directly to the outside of the enclosure through the drain port that penetrates the enclosure wall, preventing the accumulation inside the dehumidification compartment and the problem of secondary evaporation and humidification. The topmost guide plate is covered with moisture-absorbing material, which can absorb residual gaseous water vapor when air flows through it, further reducing the humidity of the air entering the electrical core room and reducing the probability of faults such as condensation and corrosion on the surface of components and leakage and short circuits in the wiring. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the power metering box of the present invention. Figure 1 ; Figure 2 for Figure 1 Sectional view of AA in the middle; Figure 3 for Figure 2 Enlarged view at point C; Figure 4 for Figure 1 Cross-sectional view of the middle section (BB); Figure 5 for Figure 4 Enlarged view at point D; Figure 6 for Figure 4 Enlarged view at point E in the middle; Figure 7 This is a partial cross-sectional schematic diagram of the through-hole structure of the present invention; Figure 8 This is a schematic cross-sectional view of the dehumidification pre-cooling chamber of the present invention; Figure 9 This is a schematic diagram of the overall structure of the power metering box of the present invention. Figure 2 ; Figure 10 for Figure 9 Enlarged view at point F; Figure 11 for Figure 9 Enlarged view at point G; Figure 12This is a schematic diagram of the structure of the first perforated grid plate of the present invention.

[0023] In the diagram, 1-box body; 2-wall panel; 21-accommodating space; 22-fully open limit stop; 23-fully closed limit stop; 3-heat dissipation window; 4-heat dissipation module; 41-first perforated grille; 42-second perforated grille; 43-guide rail; 44-ball bearing; 441-rotating shaft; 45-drive mechanism; 451-reset spring; 46-through hole; 461-straight section; 462-flared section; 463-first specification hole; 464-second specification hole; 4 7-Dovetail groove; 471-Settling groove one; 48-Dovetail slider; 481-Settling groove two; 49-Third perforated grid plate; 5-Dehumidification pre-filter; 50-Moisture-absorbing material; 51-Baffle channel; 52-Hydrophilic coating area; 53-Superhydrophobic coating area; 54-Guide groove; 541-Guide ridge one; 55-Drain outlet; 56-Guide plate one; 561-Guide ridge two; 57-Guide plate two; 58-Guide plate three; 59-Guide rib; 6-Electrical core chamber. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1: An energy metering box with an adjustable heat dissipation module includes a box body 1. A heat dissipation window 3 is provided on the wall panel 2 of the box body 1. A heat dissipation module 4 is installed at the heat dissipation window 3. The heat dissipation module 4 includes a first perforated grid plate 41 and a second perforated grid plate 42 stacked sequentially along the normal direction of the wall panel 2. The first perforated grid plate 41 and the second perforated grid plate 42 are both distributed with regularly arranged through holes 46. A guide slide rail 43 is provided inside the box body 1. The first perforated grid plate 41 is installed on the guide slide rail 43. The second perforated grid plate 42 is fixed inside the box body 1. One end of the first perforated grid plate 41 is fixedly connected to the wall panel 2 through a drive mechanism 45, and the other end is fixedly connected to the inner wall of the receiving space 21 of the wall panel 2 through a reset tension spring 451. The enclosure 1 also includes a dehumidification pre-cooling chamber 5 and an electrical core chamber 6. The dehumidification pre-cooling chamber 5 is located between the heat dissipation module 4 and the electrical core chamber 6, and the dehumidification pre-cooling chamber 5 is equipped with a drain outlet 55.

[0026] The driving mechanism 45 is a temperature-driven component, which is a shape memory alloy spring. The preload of the return spring 451 is less than the output thrust of the shape memory alloy spring after it reaches the phase transition temperature, so that the shape memory alloy spring can overcome the tension of the return spring 451 and drive the first perforated grid plate 41 to move when it elongates at high temperature. In this embodiment, the driving mechanism 45 is a nickel-titanium based shape memory alloy spring.

[0027] The inner wall of the accommodating space 21 of the wall panel 2 is equipped with rigid limiting blocks, which correspond to the two extreme positions of the first perforated grid plate 41: fully open and fully closed. When the shape memory alloy spring extends and pushes the grid plate to the maximum ventilation stroke, the side of the first perforated grid plate 41 abuts against the fully open limiting block 22, limiting the grid plate to continue to move, preventing the alloy spring from being overstretched and causing plastic deformation and permanent loss of its shape memory properties; when shrinking and resetting at low temperature, the fully closed limiting block 23 prevents the grid plate from continuously retracting, preventing the shape memory alloy spring from being squeezed and overloaded, while ensuring that the through hole 46 is completely misaligned, preventing the continuous infiltration of water vapor and electromagnetic waves caused by tiny ventilation gaps. The limiting blocks are integrally stamped into the sheet metal wall of the accommodating space 21, requiring no additional assembly parts and not occupying the layout space of the electrical core room 6.

[0028] The guide rail 43 is provided with a dovetail groove 47, and the bottom of the first perforated grid plate 41 is provided with a dovetail slider 48 that matches the dovetail groove 47. The dovetail slider 48 is embedded in the dovetail groove 47 and slides along the extension direction of the dovetail groove 47. The dovetail groove 47 has several recessed grooves 471 on its inclined surface. A ball bearing 44 is fixedly mounted on the recessed groove 471 by several rotating shafts 441. The dovetail slider 48 has a recessed groove 481 on its inclined surface that contacts the dovetail groove 47. The size of the recessed groove 481 matches that of the ball bearing 44. When the dovetail slider 48 slides along the extension direction of the dovetail groove 47, the ball bearing 44 in the recessed groove 471 rolls around the rotating shaft 441.

[0029] Specifically, the interior of enclosure 1 houses various heat-generating electrical components such as metering chips and communication modules. The heat generated by these components during continuous operation accumulates within the enclosure 1. External air needs to be introduced through the ventilation window 3 to facilitate convection heat exchange, thereby controlling the internal temperature of enclosure 1 and preventing high temperatures from affecting the metering accuracy and operational stability of the electrical components. The external environment contains high-frequency electromagnetic radiation from base stations and wireless devices. This radiation can easily penetrate enclosure 1 through the ventilation structure, interfering with the internal low-voltage sampling circuitry. Therefore, the ventilation channels need to be shielded to ensure accurate transmission of metering data. Outdoor air constantly carries moisture and dust. Direct entry of this air into enclosure 1 can cause condensation on metal components and circuit boards, leading to corrosion, leakage, and other malfunctions. Therefore, a dehumidification pre-filter 5 needs to be installed along the airflow path to the electrical core chamber 6 to pre-separate the liquid moisture carried within the airflow.

[0030] The first perforated grid plate 41 and the second perforated grid plate 42 switch the on / off state of the ventilation channel by relative sliding. The opening degree needs to be automatically adjusted according to the temperature inside the box. At the same time, the two grid plates must be kept in close contact during the sliding operation to reduce electromagnetic wave leakage gaps. It is also necessary to reduce the jamming and wear problems caused by sliding friction. The drive mechanism 45 made of shape memory alloy material, together with the reset spring 451, can realize the electric control-free passive temperature sensing drive. The combination structure of guide rail 43, dovetail groove 47, dovetail slider 48 and ball 44 can constrain the sliding trajectory of the first perforated grid plate 41, while weakening the sliding resistance, maintaining the continuous conduction of the metal contact surface of the two grid plates, and ensuring a complete electromagnetic shielding circuit.

[0031] A heat dissipation module 4 is installed at the heat dissipation window 3 of the wall panel 2 of the enclosure 1. Inside the heat dissipation module 4, the first perforated grid plate 41 and the second perforated grid plate 42 are stacked together along the normal direction of the wall panel 2. The second perforated grid plate 42 remains fixed, while the first perforated grid plate 41 can move along the guide rail 43. When the internal temperature of the enclosure 1 is within the normal range, the shape memory alloy spring corresponding to the drive mechanism 45 remains in a contracted state. The tension of the return spring 451 pulls the first perforated grid plate 41, so that the through holes 46 on the first perforated grid plate 41 and the through holes 46 on the second perforated grid plate 42 form a staggered arrangement. Airflow cannot pass through the two grid plates, and the heat dissipation window 3 is in a closed state. External moisture, dust and electromagnetic radiation are difficult to enter the interior of the enclosure 1.

[0032] After the internal temperature of the housing 1 rises to the phase transition temperature of the shape memory alloy spring, the drive mechanism 45 undergoes elongation deformation. The thrust generated by the drive mechanism 45 is greater than the preload of the return spring 451, which drives the first perforated grid plate 41 to move along the guide rail 43. The through holes 46 of the first perforated grid plate 41 gradually align and connect with the through holes 46 of the second perforated grid plate 42, forming a ventilation channel that runs through the normal direction of the wall panel 2. External air can flow into the housing 1 through the through holes 46. The airflow will first pass through the dehumidification pre-chamber 5 and then reach the electrical core chamber 6. The moisture extracted inside the airflow will be discharged from the housing 1 through the drain port 55 of the dehumidification pre-chamber 5.

[0033] The guide rail 43 has a dovetail groove 47. The dovetail slider 48 at the bottom of the first perforated grid plate 41 is embedded in the dovetail groove 47. The dovetail structure restricts the first perforated grid plate 41 to move only along the extension direction of the guide rail, and prevents offset and warping in the direction perpendicular to the plate surface. The first countersunk groove 471 of the dovetail groove 47 is machined on the inclined surface and a ball bearing 44 is installed through the pivot 441. The dovetail slider 48 has a second countersunk groove 481 of the same size on the inclined surface. When the first perforated grid plate 41 moves, the ball bearing 44 will roll around the pivot 441 between the first countersunk groove 471 and the second countersunk groove 481. The sliding friction of the metal components directly contacting each other is transformed into rolling friction, reducing the resistance of the sliding process. The ball bearing 44 continuously contacts the metal contact surface of the dovetail groove 47 and the dovetail slider 48. The two grid plates maintain equipotential connection throughout the sliding process, and there will be no gaps of electrical disconnection in the complete shielded cavity.

[0034] The wall panel 2 of the box body 1 is provided with a receiving space 21. One end of the reset spring 451 is connected to the first perforated grid plate 41 and the other end is fixed to the inner wall of the receiving space 21. After the internal temperature of the box body 1 drops, the drive mechanism 45 retracts and resets. The reset spring 451 pulls the first perforated grid plate 41 to slide in the opposite direction, and the through holes 46 are restored to their misaligned distribution, and the ventilation channel is closed again.

[0035] The alignment and misalignment of the through holes 46 are controlled by the sliding of the two-layer grid plates. When the ventilation channel is open, the depth of the through hole 46 is greater than the diameter of the hole itself. Relying on the metal waveguide cutoff principle, the penetration ability of high-frequency electromagnetic waves is weakened. During the ventilation process when the heat dissipation window 3 is open, the enclosure 1 can still maintain electromagnetic shielding performance, and external electromagnetic radiation is unlikely to interfere with the metering and communication components inside the electrical core chamber 6. Under low-temperature conditions, the misalignment and sealing of the through holes 46 significantly reduces the total amount of external moisture and dust entering the enclosure 1, reducing the probability of corrosion and damage to components.

[0036] The drive mechanism 45 uses a shape memory alloy spring as a passive temperature sensing component, eliminating the need for additional temperature sensors, control circuit boards, and power supply lines. It relies on the material's own temperature deformation to achieve automatic drive, reducing the probability of electrical component failures and making it suitable for long-term unattended outdoor operation. The preload of the reset spring 451 is set far below the high-temperature elongation thrust of the shape memory alloy spring. In high-temperature environments, the drive mechanism 45 can smoothly push the first perforated grid plate 41 to complete the window opening action. After the temperature drops, the reset spring 451 provides a stable pull-back force, preventing insufficient shrinkage force of the shape memory alloy at low temperatures from causing the ventilation window to not close properly and leaving an electromagnetic leakage path.

[0037] The limiting structure of the dovetail groove 47 and the dovetail slider 48 can form a bidirectional constraint on the first perforated grid plate 41. During the sliding process, the grid plate will not warp on one side, and the two grid plates will always be tightly fitted, preventing gaps that allow electromagnetic waves to penetrate due to grid plate separation. The first groove 471, the rotating shaft 441, the ball bearing 44, and the second groove 481 form a rolling fit structure, significantly reducing sliding resistance. Even if dust enters the gap between the dovetail groove 47 and the dovetail slider 48, it is less likely to cause sliding jamming, extending the overall service life of the guide structure. The ball bearing 44 continuously connects the metal contact surfaces of the dovetail groove 47 and the dovetail slider 48, ensuring that the conductive circuit of the shielding cavity is not interrupted during sliding, avoiding the problem of shielding failure caused by the formation of an insulating oxide layer on the metal contact surface.

[0038] After entering the housing 1, the airflow first flows through the heat dissipation module 4 and then into the dehumidification pre-chamber 5. Moisture is separated within the dehumidification pre-chamber 5, and only the dried airflow enters the electrical core chamber 6. This reduces the probability of condensation on electrical components and short circuits / corrosion. The drain outlet 55 of the dehumidification pre-chamber 5 directly discharges the separated liquid water from the housing 1, preventing moisture accumulation inside and further increasing air humidity. The entire structure relies on natural convection for heat exchange, eliminating the need for additional fans, cooling, or heating components, resulting in lower overall energy consumption and controllable maintenance costs for long-term outdoor use.

[0039] Example 2: The through hole 46 includes a straight cylindrical section 461 and flared sections 462 located at both ends of the straight cylindrical section 461. The diameter of the flared section 462 gradually increases in the direction away from the straight cylindrical section 461. The through holes 46 on the first perforated grid plate 41 and the second perforated grid plate 42 are arranged in a multi-row array. The through hole array alternates between first-specification holes 463 and second-specification holes 464 along the row direction. The first-specification holes 463 are arranged in odd-numbered rows and the second-specification holes 464 are arranged in even-numbered rows. The diameter of the first-specification hole 463 is the maximum allowable through hole diameter calculated according to the electromagnetic shielding cutoff hole diameter formula. The diameter of the second-specification hole 464 is smaller than the diameter of the first-specification hole 463. The first specification hole 463 and the second specification hole 464 are staggered along the plate plane. When the first perforated grid plate 41 is translated relative to the second perforated grid plate 42, the first specification hole 463 and the second specification hole 464 can form a multi-level overlapping and connected ventilation channel.

[0040] The heat dissipation module 4 also includes a third perforated grid plate 49, which is disposed on the side of the second perforated grid plate 42 away from the first perforated grid plate 41. The structure of the third perforated grid plate 49 is the same as that of the first perforated grid plate 41. At the position of the third perforated grid plate 49, the housing 1 is provided with a guide rail 43, a dovetail groove 47, a dovetail slider 48, a first recess 471, a ball bearing 44, a rotating shaft 441, and a second recess 481, which are the same as those of the first perforated grid plate 41. One end of the third perforated grid plate 49 is fixedly connected to the wall panel 2 through a driving mechanism 45, and the other end is fixedly connected to the inner wall of the receiving space 21 of the wall panel 2 through a reset spring 451. The third perforated grid plate 49 has through holes 46 distributed on it. Under the drive of the driving mechanism 45, the through holes 46 on the third perforated grid plate 49 are aligned and connected with the through holes 46 on the second perforated grid plate 42.

[0041] In the initial state, the through holes 46 on the first perforated grid plate 41 and the second perforated grid plate 42 are misaligned. When the temperature is high, the drive mechanism 45 extends and drives the first perforated grid plate 41 to move relative to the second perforated grid plate 42 along the guide rail 43, so that the through holes 46 on the two are aligned and connected, forming a ventilation channel array that runs through the normal direction of the wall plate 2 and the channel depth is greater than the hole diameter.

[0042] The first perforated grid plate 41, the second perforated grid plate 42, the third perforated grid plate 49, the guide slide rail 43, and the dovetail slider 48 are all made of 0.8mm thick 304 stainless steel sheet metal integral stamping. The stainless steel base has stable metal conductivity. The entire sliding shielding structure has no insulation separation and naturally forms a continuous equipotential shielding cavity.

[0043] The ball bearing 44 is made of silver-plated stainless steel solid ball bearing. The base is 420 stainless steel and the surface is electroplated with a 0.03mm thick pure silver conductive coating. The silver layer has high conductivity and is not easily oxidized in outdoor humid environments to form an insulating passivation film. During the sliding process, the ball bearing 44 always keeps in contact with the metal contact surface of the dovetail groove 47 and the dovetail slider 48. No matter where the grid plate is in any translation position, the conductive connection between the slide rail and the grid plate can be maintained, and the shielding circuit will not have an electrical break due to sliding friction.

[0044] Specifically, during operation, the electricity metering box relies on through-holes 46 to achieve air convection and heat dissipation between the inside and outside of the box. However, the channels formed by the through-holes 46 cannot significantly weaken the overall electromagnetic shielding capability of the box. A single-size arrangement of through-holes makes it difficult to simultaneously balance ventilation flow and electromagnetic attenuation. Furthermore, an array structure with uniform apertures is prone to resonance in specific electromagnetic frequency bands, leading to a decrease in localized shielding performance. The through-hole structure with a straight section 461 and flared sections 462 at both ends reduces airflow resistance and improves convective heat transfer efficiency while maintaining the required aperture size for waveguide shielding. Distinguishing between first-size apertures 463 and second-size apertures 464 and arranging them alternately along the row allows for the use of the larger first-size apertures 463 to ensure overall ventilation area, adapting to heat dissipation requirements under high-temperature and high-load conditions. Simultaneously, the smaller second-size apertures 464 enhance the attenuation effect of high-frequency electromagnetic waves. The staggered arrangement of the two apertures also breaks the array's periodicity, avoiding the shielding effectiveness degradation caused by resonance.

[0045] During the translation of the first perforated grid plate 41 relative to the second perforated grid plate 42, the two aperture sizes overlap and conduct in stages, enabling a gradual change in ventilation area and avoiding drastic temperature fluctuations inside the enclosure. Adding a third perforated grid plate 49 superimposed on the outside of the second perforated grid plate 42 extends the overall path length of electromagnetic waves through the ventilation channel, improving shielding attenuation in scenarios with dense base stations and radio frequency equipment, thus broadening the applicable environment range of the equipment. Controlling the initial misalignment of the through holes 46 between the first and second perforated grid plates 41 and 42 prevents external moisture and dust from entering the enclosure under low-temperature conditions. As the temperature rises, the through holes 46 are aligned to form a through channel with a depth greater than the aperture, continuously blocking external electromagnetic radiation when ventilation is open, relying on the waveguide cutoff effect.

[0046] The straight cylindrical section 461 in the middle of the through-hole 46 determines the core aperture size of the waveguide channel. This size matches the control standard calculated by the electromagnetic shielding cutoff aperture formula, enabling attenuation and suppression of high-frequency electromagnetic waves in a specified frequency band. The straight cylindrical section 461 extends outwards at both ends with flared sections 462. The cross-sectional size of the flared sections 462 continuously expands away from the straight cylindrical section 461, preventing significant airflow resistance due to abrupt changes in cross-section when air flows into and out of the through-hole 46. Multiple rows of through-holes 46 are arrayed on the surfaces of the first perforated grid plate 41 and the second perforated grid plate 42. Odd-numbered rows are entirely arranged with first-specification holes 463, while even-numbered rows are entirely arranged with second-specification holes 464, which have smaller diameters. The two types of holes are staggered in their projected positions on the plate surface, preventing the formation of a completely vertically aligned through-channel. The first-specification hole 463 is 6mm, and the second-specification hole 464 is 5mm.

[0047] The electromagnetic shielding mechanism of aperture arrays is based on the waveguide cutoff principle: for a given aperture size, there exists a cutoff frequency below which electromagnetic waves cannot propagate effectively within the aperture, but instead attenuate exponentially. Taking a circular aperture array as an example, its cutoff frequency satisfies:

[0048] In the formula, The cutoff frequency of the channel. The speed of light in a vacuum is 3 × 10⁻⁶. 8 m / s, The equivalent radius of the 46-hole aperture is given, and the coefficient 1.841 represents the circular waveguide TE. 11 The zero-point value of the first derivative of the Bessel function corresponding to the pattern. The typical interference frequency band of 5G and base stations around the smart grid is taken as 2.4GHz. The theoretical maximum cutoff aperture D=2r is calculated to be 73.25mm. This theoretical value is much greater than 6mm, indicating that the cutoff frequency corresponding to the 6mm aperture is much higher than 2.4GHz, which can completely shield communication interference at 2.4GHz and below, and meet the shielding requirements of the metering box. 6mm is the safe maximum aperture selected for this embodiment project, which maximizes the ventilation flow of a single hole without exceeding the shielding threshold.

[0049] The first perforated grid plate 41 and the second perforated grid plate 42 are stamped with a multi-row alternating variable diameter through-hole array. Odd-numbered rows are uniformly machined with first-specification through-holes of 6mm diameter, and even-numbered rows are uniformly machined with second-specification through-holes of 5mm diameter. According to the circular waveguide cutoff frequency calculation formula described in this invention, the electromagnetic wave cutoff frequency corresponding to the 6mm through-hole is much higher than the 2.4GHz public communication interference frequency band, which can achieve basic shielding against high-frequency electromagnetic radiation outside the box while ensuring the maximum ventilation cross-sectional area. The 5mm second-specification through-hole has a smaller diameter, and the waveguide channel has a larger attenuation coefficient for high-frequency electromagnetic waves. It forms an interlaced shielding barrier with the adjacent row of 6mm large holes. After external electromagnetic waves pass through the 6mm large holes, they will be attenuated by secondary reflection from the underlying 5mm small hole solid ribs.

[0050] Two aperture sizes are arranged alternately along rows and columns, breaking the periodic resonance condition of equal-diameter through-hole arrays and avoiding the defect of a sudden drop in shielding effectiveness at a specific frequency for single-aperture arrays. When airflow passes through the alternating 6mm and 5mm through-holes, turbulence is generated, enhancing convective heat transfer on the surface of components inside the enclosure. When the coaxial direct-drive shape memory alloy component pushes the first perforated grid plate to translate, the 6mm and 5mm through-holes align step by step, and the ventilation penetration area changes continuously and smoothly with the grid plate displacement, achieving stepless fine adjustment of heat dissipation airflow. At the same time, the metal ribs of the grid plate in the area where the 5mm small hole is located are wider, improving the deformation resistance of the entire perforated grid plate and avoiding long-term sliding and warping that could lead to poor adhesion between the two grid layers and electromagnetic wave leakage.

[0051] When the diameter of through hole 46 is designed to make When the electromagnetic wave frequency is higher than the normal operating frequency band required by the metering and communication system inside the enclosure, but lower than the high-frequency interference band that needs to be shielded, the electromagnetic wave in that frequency band will attenuate exponentially within the channel, with an attenuation coefficient of:

[0052] In the formula, The attenuation coefficient is... To be related to the cutoff frequency The corresponding cutoff wavelength, The actual frequency of the intruding electromagnetic wave. After passing through a depth of... After the channel is formed, the total attenuation of the electromagnetic wave is:

[0053] In the formula, This represents the total attenuation. The thickness of the overlap between the first perforated grid plate 41 and the second perforated grid plate 42 in their aligned state is called the channel depth. From the above formula, we can see that the channel depth... The larger the relative aperture, the more significant the attenuation effect. Therefore, the present invention designs the stacking thickness of the two grid plates to be greater than the aperture of the through hole 46, so as to ensure that the aligned channel has a sufficient attenuation depth-to-diameter ratio. This allows the ventilation channel array to meet the requirements of the air convection channel while effectively blocking the target high-frequency interference band. Since the array is still a through channel in geometry, air can flow freely along the channel without being hindered by the electromagnetic cutoff effect. This achieves the effect of both ventilation and shielding performance when the heat dissipation opening is open.

[0054] When the internal temperature of the enclosure has not reached the phase change temperature of the drive mechanism 45, the through holes 46 of the first perforated grid plate 41 and the second perforated grid plate 42 are misaligned, and the airflow cannot penetrate the two grid plates along the normal direction of the wall panel 2, so the heat dissipation channel is in a closed state. When the internal temperature of the enclosure rises, it triggers the drive mechanism 45 to elongate and deform. The drive mechanism 45 drives the first perforated grid plate 41 to translate along the guide rail 43. During the translation, the larger first specification hole 463 first gradually aligns to form a basic ventilation passage. After the movement continues, the second specification hole 464 successively overlaps. The ventilation passage area changes continuously with the displacement of the grid plate, forming a multi-level gradually changing ventilation channel array.

[0055] The third perforated grille 49 added to the heat dissipation module 4 is arranged on the side of the second perforated grille 42 away from the first perforated grille 41. The overall structure of the third perforated grille 49 is consistent with that of the first perforated grille 41. It also has a first specification hole 463 and a second specification hole 464 with a straight section 461 and a flared section 462. The third perforated grille 49 is connected to the second perforated grille 42 by means of the guide rail 43. When the drive mechanism 45 completes the translational movement of the grille, the through hole 46 of the third perforated grille 49 is aligned and connected with the through hole 46 of the second perforated grille 42. The total depth of the through channel formed by the three layers of grilles is greater than the diameter of a single set of through holes 46. After the external high-frequency electromagnetic waves enter the channel, they will be continuously reflected and attenuated in the long metal channel, making it difficult to penetrate the multi-layer grille and reach the electrical component area inside the cabinet.

[0056] Outside air flows into the enclosure through the multi-layered aligned array of through-holes 46. After being buffered by the flared section 462, the airflow smoothly passes through the straight section 461, completing the heat exchange inside the enclosure 1. High-frequency electromagnetic waves carried by the outside air undergo exponential loss in the slender metal channels, whose depth is greater than the aperture, following the waveguide cutoff law, and cannot penetrate the multi-layered grid to interfere with the metering chip and communication module. After the internal temperature of the enclosure drops, the drive mechanism 45 retracts and resets, the first perforated grid 41 slides in the opposite direction, and the first specification hole 463 and the second specification hole 464 are restored to their staggered arrangement, completely isolating the through ventilation channel.

[0057] The through-hole 46 adopts a combination structure of a straight cylindrical section 461 and a flared section 462. The straight cylindrical section 461 can stably maintain the aperture standard required for electromagnetic shielding, ensuring that the electromagnetic wave attenuation effect is not affected. The flared section 462, which gradually widens at both ends, can reduce eddy current losses when airflow enters and exits the through-hole 46. Under the same total opening area, the air convection velocity is increased, and the heat dissipation efficiency is improved accordingly. The gradual contour of the flared section 462 can also play a buffering and guiding role during the translation and alignment of the first perforated grid plate 41 with the through-hole 46, reducing the sliding and jamming caused by the mutual scraping of the hole edges, and extending the overall service life of the grid plate.

[0058] The alternating arrangement of the first-size holes 463 and the second-size holes 464 along the row balances ventilation flow and shielding performance. The first-size hole 463 uses the calculated maximum allowable through-hole diameter, ensuring that the overall flow area meets the high-temperature heat dissipation requirements. The second-size hole 464 has a smaller diameter, and the electromagnetic wave cutoff frequency corresponding to a single hole is higher, which can form a secondary blocking and attenuation effect on the residual electromagnetic waves that penetrate the first-size hole 463. The alternating arrangement of the two types of hole diameters disrupts the periodic symmetry structure of the through-hole array, eliminates the resonance phenomenon generated when electromagnetic waves of specific frequency bands pass through the array, avoids a significant decline in the shielding effectiveness of the corresponding frequency band, and stabilizes the electromagnetic blocking effect across the entire frequency band. The staggered arrangement of large and small hole diameters can also widen the width of the local metal ribs on the grid plate surface, improve the planar stiffness of the first perforated grid plate 41 and the second perforated grid plate 42, and the grid plate is less prone to warping deformation after long-term reciprocating translation. The two grid plates can maintain a tight fit and reduce the electromagnetic wave leakage gaps caused by grid plate separation.

[0059] During the translation of the first perforated grid plate 41, the first specification holes 463 and the second specification holes 464 are aligned and connected in stages. The ventilation area can be adjusted smoothly with the displacement of the grid plate, without sudden increases or decreases in ventilation volume. The internal temperature change of the enclosure 1 is more stable, avoiding drift in sampling accuracy of the metering element due to drastic temperature fluctuations. Adding a third perforated grid plate 49 can increase the overall thickness of the ventilation channel, further lengthening the electromagnetic wave attenuation path. When used in outdoor locations with high electromagnetic interference intensity, it can still maintain qualified shielding performance without the need to replace the enclosure 1 with one of larger overall dimensions.

[0060] In its initial state, the staggered arrangement of the through-holes 46 completely blocks the direct airflow channels, significantly reducing the entry of external moisture and dust into the enclosure 1 at low temperatures, thus lowering the probability of electrical component corrosion and short-circuit faults. Under high-temperature conditions, the aligned through-holes 46 of the multi-layer grid form a ventilation channel array with a depth greater than the aperture. While airflow remains unobstructed, the slender metal channels continuously attenuate high-frequency electromagnetic radiation through waveguide cutoff effects, achieving simultaneous operation of heat dissipation and electromagnetic shielding functions, preventing a significant decrease in shielding performance after ventilation is activated. The three-layer grid structure reuses the same through-hole 46 arrangement, resulting in higher component interchangeability. This simplifies sheet metal stamping processes during mass production, reducing overall equipment manufacturing costs.

[0061] Example 3: The dehumidifier pre-filter 5 is equipped with multiple sequentially connected baffle channels 51, with different flow cross-sectional areas for adjacent baffle channels 51. The windward side wall of the baffle channel 51 has a hydrophilic coating area 52, and the leeward side wall has a superhydrophobic coating area 53. A guide channel 54 is located at the bottom of the dehumidifier pre-filter 5, with a guide protrusion 541 on it. One end of the guide channel 54 connects to a drain outlet 55, which penetrates the wall panel 2 of the housing 1. An elastic silicone one-way valve is embedded within the drain outlet 55. This one-way valve only allows liquid water inside the dehumidifier pre-filter 5 to drain outwards. External rainwater and water vapor, under water pressure, will press the valve plate to seal the channel, preventing rainwater from flowing back into the housing 1 and causing short circuits in components due to moisture. The silicone material of the one-way valve is resistant to salt spray and high / low temperatures, making it suitable for long-term outdoor use in coastal or open-air environments.

[0062] The hydrophilic coating area 52 on the windward side wall of the deflector channel 51 uses a titanium dioxide-based inorganic hydrophilic coating. The main components are nano-titanium dioxide and silica sol binder. It contains no organic resin components and will not powder or peel off under long-term outdoor ultraviolet radiation. The water contact angle of the coating is less than 10°, and water mist spreads quickly to form a continuous water film after contact. The superhydrophobic coating area 53 on the leeward side wall uses a fluorine-modified inorganic ceramic coating. It does not contain easily aged organic fluorine resins. The surface water contact angle is greater than 145°, and water droplets roll off directly without adhesion after contact.

[0063] Both types of coatings are attached to the metal wall of the baffle channel 51 using a high-temperature sintering process. Weather resistance tests show that they can stably maintain hydrophilic and hydrophobic properties for more than 8 years. They will not peel or fail under outdoor day and night temperature differences, salt spray, and ultraviolet radiation. There is no problem of coating peeling and loss of water vapor separation ability after long-term use.

[0064] Specifically, the high-power, high-heat-generating intelligent metering box integrates multiple acquisition terminals, edge computing units, multiple high-power wiring terminals, and wireless radio frequency communication modules. When the equipment operates under high load for a long time, it continuously releases a large amount of heat. At the same time, high humidity air, high-frequency electromagnetic interference, and dust impurities in the outdoor environment will simultaneously have multiple negative impacts on the precision metering devices inside the box. The structure of conventional metering boxes, which only have narrow side wall ventilation gaps, cannot simultaneously meet the multi-dimensional protection and heat dissipation requirements.

[0065] This design places the dehumidification pre-cabin 5 between the heat dissipation module 4 and the electrical core chamber 6, which will occupy a section of fixed cavity space inside the enclosure. This will directly reduce the usable area of ​​the electrical core chamber 6 for arranging the electricity meter and line terminals. It is equivalent to sacrificing some of the installation space inside the enclosure as a design cost. However, this cavity integrates multiple functions such as ventilation buffer, multi-stage water vapor separation, secondary electromagnetic wave attenuation, and dust interception, resulting in multiple benefits in terms of overall performance.

[0066] When external air enters the box 1 through the heat dissipation module 4, the airflow often carries water vapor. Direct contact with the internal components of the electrical core chamber 6 can easily lead to condensation, causing problems such as corrosion of metal parts and reduced insulation of circuit boards. Therefore, water vapor separation needs to be completed before the airflow reaches the electrical core chamber 6. A dehumidification pre-chamber 5 is set up as the chamber through which the air enters. The baffle channel 51 adopts a structure with different cross-sectional areas of adjacent sections. The purpose is to make the airflow velocity change continuously, causing the water mist particles carried in the airflow to be precipitated. The water vapor is then collected by the wall coating. The precipitated liquid water needs to be collected and discharged from the box 1 in a timely manner to prevent water from accumulating in the chamber and evaporating again to humidify the internal air. The guide channel 54, together with the guide protrusion 541 and the drain outlet 55, is used to complete the collection and discharge of liquid water. The deflection channel 51 distinguishes the hydrophilic coating area 52 on the windward side wall and the superhydrophobic coating area 53 on the leeward side wall in order to adsorb and guide gaseous water vapor and condensed liquid water droplets respectively, thereby reducing the situation where small water droplets are re-entrained into the electrical core chamber 6 by the airflow.

[0067] After entering the dehumidification pre-compartment 5, the air carrying moisture flows forward along the baffle channel 51. The cross-sectional areas of adjacent baffle channels 51 differ, and the airflow velocity decreases in the section with the larger cross-sectional area, thus reducing the air's ability to hold moisture. Some suspended water droplets detach from the airflow and impact the inner wall of the channel. When the airflow flows into the section with a narrower cross-sectional area, the airflow velocity increases again, and the flow direction deflects along with the baffle channel 51. The water droplets inside the airflow continue to move forward due to inertia, further impacting and adhering to the channel wall. When the airflow impacts the windward side wall of the baffle channel 51, the hydrophilic coating area 52 captures the water mist in the airflow. After continuous accumulation, a continuous water film forms on the wall surface. This water film flows downwards along the wall surface to the leeward side wall. The superhydrophobic coating area 53 on the leeward side wall reduces the adhesion between the water droplets and the wall surface, preventing the collected liquid water droplets from adhering to the wall surface and allowing them to slide down the wall to the bottom of the compartment. The liquid water droplets that slide down collect inside the guide channel 54 at the bottom of the dehumidification pre-compartment 5. The guide protrusions 541 arranged on the guide channel 54 can guide and constrain the water flow, preventing the water from spreading everywhere in the channel. The liquid water flows continuously along the guide channel 54 to the drain outlet 55, and finally is discharged directly to the outside of the box 1 through the drain outlet 55 that penetrates the wall panel 2 of the box 1.

[0068] The multiple flow channels 51 with varying cross-sectional areas can repeatedly change the airflow velocity and flow state. Compared to a straight channel with a consistent cross-section, the probability of water mist particles colliding with the channel wall is increased, allowing more water vapor to separate from the air and reducing the humidity of the air flowing into the electrical core chamber 6. The hydrophilic coating area 52 is arranged on the windward side wall, where the airflow directly impacts, effectively capturing fine water mist within the airflow and facilitating the formation of a water film. The superhydrophobic coating area 53 is arranged on the leeward side wall, allowing the collected liquid water droplets to quickly detach from the wall, reducing the phenomenon of water droplets being re-blown away by the airflow to form fine mist droplets and lowering the risk of secondary water carryover. The guide channel 54 receives liquid water sliding down from various points in the flow channels 51, and the guide ridge 541 can constrain the water flow direction, preventing water from accumulating locally at the bottom of the dehumidification pre-chamber 5. The accumulated water will not remain inside the chamber for a long time, thus preventing the water from evaporating again and increasing the humidity inside the chamber 1. The drain outlet 55 directly penetrates the wall panel 2 of the housing 1, allowing the separated liquid water to be directly discharged to the outside of the housing 1. Water vapor will not enter the electrical core chamber 6 and come into contact with metering and communication components, reducing malfunctions such as leakage, short circuits, and corrosion of metal parts caused by condensation. The entire water vapor separation structure relies on the airflow itself to complete the water mist extraction, eliminating the need for additional heating or adsorption consumables. The equipment itself does not require additional power consumption, and there is no need for maintenance such as replacing aging consumables, making it suitable for long-term unattended operation of outdoor power metering boxes.

[0069] In Example 4, the dehumidification pre-filter compartment 5 is provided with several sets of guide plates 56, 57, and 58 that gradually slope towards the heat dissipation module 4 along the width of the housing 1. This facilitates the flow of droplets along the guide plates 56, 57, and 58 to the drain outlet 55. The guide plates 56, 57, and 58 are connected in sequence. The tail end of the guide plate 58 is provided with a guide ridge 59 to guide the droplets to the drain outlet 55. The top and bottom surfaces of the guide plates 56, 57, and 58 are provided with several evenly distributed guide ridges 561 to facilitate droplet guidance. The uppermost guide plates 56, 57, and 58 are provided with moisture-absorbing material 50 to assist in moisture absorption.

[0070] Specifically, some of the liquid water droplets that precipitate from the dehumidification pre-filter chamber 5 through the baffle channel 51 will float and remain suspended in the chamber space, while others will drip down from the wall of the baffle channel 51. Without corresponding receiving and guiding components, the droplets are prone to splashing everywhere, and some droplets will be carried back by the flowing airflow and follow the airflow to the electrical core chamber 6, causing damage to the internal electrical components. At the same time, some water vapor does not condense completely and remains mixed in the airflow in a gaseous form. Simply relying on the baffle collision condensation cannot completely remove this gaseous water vapor, and corresponding structures are needed to further treat the residual water vapor. Inside the dehumidification pre-filter chamber 5, guide plates 1 56, 2 57, and 3 58 are arranged along the width of the chamber 1. These plates are gradually tilted towards the heat dissipation module 4 to receive the dripping and splashing liquid droplets in the chamber, guide the droplets to flow in a directional manner, and, together with the guide rib 59, direct the water to the drain outlet 55 to prevent the droplets from scattering randomly. The guide strips 561 arranged on the surfaces of guide plates 56, 57, and 58 can constrain the flow path of droplets and reduce the spread and overflow of droplets on the surface. The moisture-absorbing material 50 configured on the top guide plates 56, 57, and 58 is used to absorb residual gaseous water vapor in the airflow that has not yet condensed, further reducing the humidity of the air entering the electrical core chamber 6.

[0071] As the airflow flows inside the dehumidification pre-filter compartment 5, the precipitated droplets fall onto the surfaces of the first guide plate 56, the second guide plate 57, and the third guide plate 58. These plates are connected in sequence and tilted towards the heat dissipation module 4. The droplets falling onto the plates will flow along the height difference created by the tilt of the plates. The guide ridges 561, evenly distributed on the top and bottom surfaces of the first guide plate 56, the second guide plate 57, and the third guide plate 58, limit the flow of droplets. The droplets will converge and travel along the direction of the guide ridges 561, preventing them from spreading out on the plate surface to form a large water film, and also preventing them from being easily dispersed into fine mist droplets by airflow disturbances. The droplets flow sequentially along guide plate 1 56, guide plate 2 57, and guide plate 3 58, reaching the tail end of guide plate 3 58. The guide ridge 59 gathers the collected droplets, directing the dispersed water to the drain outlet 55, allowing the liquid water to be discharged out of the housing 1. The air flowing through the upper plate will come into contact with the moisture-absorbing material 50. The residual gaseous water vapor in the air will be absorbed by the moisture-absorbing material 50. After being treated by the moisture-absorbing material 50, the air continues to travel towards the electrical core chamber 6.

[0072] The first guide plate 56, the second guide plate 57, and the third guide plate 58 are spliced ​​together to form a continuous receiving surface, which can catch droplets falling from various parts of the baffle channel 51, reduce irregular splashing of droplets, and reduce the probability of droplets being carried away by secondary entrainment by the airflow. The second guide strip 561 set on the plate surface can accelerate the speed of droplet convergence and flow, shorten the residence time of droplets on the plate surface, and reduce the risk of corrosion caused by prolonged adhesion of liquid water to the plate surface. The guide ridge 59 at the tail end of the third guide plate 58 gathers the dispersed water flow, preventing the water flow from scattering at the end of the plate body, ensuring that most of the liquid water can flow to the drain outlet 55, reducing water accumulation inside the dehumidification pre-compartment 5. The moisture-absorbing material 50 arranged at the top layer can treat the gaseous water vapor in the airflow that does not condense, supplementing the condensation dehumidification of the baffle channel 51, and further reducing the humidity of the air entering the electrical core chamber 6. The entire panel structure is arranged inside the dehumidification pre-cabinet 5, without requiring additional space for the meter and wiring devices in the cabinet 1. It relies on natural airflow to treat moisture, eliminating the need for additional energy-consuming components such as fans and heating elements. The moisture-absorbing material 50 is located inside the dehumidification pre-cabinet 5 on the air intake side. Moisture vapor from the outside air is preferentially adsorbed. As the temperature inside the cabinet rises, the moisture adsorbed by the moisture-absorbing material 50 can also be released towards the heat dissipation module 4 with the airflow, achieving a certain degree of self-drying. This slows down the rate of saturation failure of the moisture-absorbing material 50, reducing the frequency of later maintenance and replacement. The moisture-absorbing material 50 is a porous mineral-based moisture-absorbing medium, including montmorillonite and diatomaceous earth. This type of material is chemically inert, has good insulation properties, and does not exhibit liquid precipitation or flow after absorbing water. It is often encapsulated in granular form inside non-woven fabric or DuPont paper breathable bags and placed inside the air ducts of distribution cabinets and metering boxes. Relying on its own porous layered structure, it adsorbs gaseous moisture in the airflow, making it suitable for passive dehumidification scenarios outdoors without heating.

[0073] The moisture-absorbing material 50 is a mixture of spherical composite molecular sieves with a particle size of 2-4mm and diatomaceous earth particles. The two media are mixed in a mass ratio of 3:7. It is encapsulated in a thin breathable bag using DuPont waterproof and breathable non-woven fabric. The thickness of a single breathable bag is 5mm. It is snap-on and detachable and installed on the upper edge of the guide plate 1 56, guide plate 2 57, and guide plate 3 58 with a reserved slot. The total filling amount is controlled to 120g of moisture-absorbing medium for each guide plate. The saturated water vapor adsorption capacity of a single bag is 42g.

[0074] Once the moisture-absorbing material 50 reaches adsorption saturation, it can achieve self-drying by relying on the high-temperature conditions inside the chamber 1: when the internal temperature of the chamber 1 is continuously higher than 50℃ and maintained for more than 40 minutes, the hot air inside the chamber flows through the moisture-absorbing material 50, and the water vapor adsorbed inside the molecular sieve and diatomaceous earth is desorbed by heat and discharged outward with the convective air through the heat dissipation module 4, restoring the adsorption capacity of the moisture-absorbing medium; the effective self-drying conditions are limited to an ambient temperature above 35℃ and a continuous heat load inside the chamber 1. There is no self-drying effect when it is rainy and the temperature inside the chamber is below 40℃. In the saturated state, the vent bag can be disassembled and replaced without replacing the entire baffle assembly.

[0075] See Figures 1-12 Explain the working process of this power box: The electricity metering box is in normal outdoor operation. The electrical core chamber 6 inside the box 1 is equipped with an electricity meter, a communication acquisition module and wiring terminals. The equipment continuously generates heat when powered on, and the ambient temperature will change with the power load and external sunlight conditions.

[0076] When the ambient temperature is not high and the internal temperature of the housing 1 has not reached the phase transition temperature of the shape memory alloy spring of the drive mechanism 45, the drive mechanism 45 remains in a contracted state. The tension of the return spring 451 acts on the first perforated grid plate 41, and the first perforated grid plate 41 stays in the initial position along the guide rail 43. The through holes 46 of the first perforated grid plate 41 and the second perforated grid plate 42 are misaligned, and the ventilation channel of the heat dissipation module 4 is blocked, so that outside air cannot directly pass through the two layers of grid plates to enter the interior of the housing 1. The third perforated grid plate 49 follows the drive mechanism 45 and maintains the corresponding position, and the through holes 46 also remain misaligned. The multiple layers of grid plates together block external dust, water vapor and external electromagnetic radiation from entering the electrical core chamber 6, and the interior of the housing 1 remains in a relatively closed state, reducing the impact of the external environment on the internal components.

[0077] When the electrical load increases or the room is exposed to direct sunlight, the internal temperature of the housing 1 gradually rises. Once the temperature reaches the phase transition temperature of the shape memory alloy spring, the drive mechanism 45 undergoes elongation deformation. The thrust generated by the drive mechanism 45 exceeds the preload of the return spring 451, causing the first perforated grid plate 41 to translate along the guide rail 43. During the movement of the first perforated grid plate 41, the dovetail slider 48 slides inside the dovetail groove 47, and the ball bearing 44 rolls around the pivot 441 between the first groove 471 and the second groove 481, reducing sliding resistance through rolling friction while maintaining equipotential conductivity between the metal components. When the first perforated grid plate 41 is translated, the first specification hole 463 is partially aligned first, and then the second specification hole 464 gradually overlaps to form a multi-level ventilation channel. The third perforated grid plate 49 moves synchronously, and the through hole 46 on it is aligned with the through hole 46 of the second perforated grid plate 42. The through holes 46 of the multi-layer grid plates are combined to form a ventilation channel array that runs through the normal direction of the wall panel 2 and the channel depth is greater than the hole diameter.

[0078] Air from the external environment enters the housing 1 through the heat dissipation window 3 and the aligned through-hole 46. The straight section 461 of the through-hole 46 maintains the channel size for waveguide attenuation, while the flared sections 462 at both ends reduce airflow resistance. High-frequency electromagnetic waves are continuously attenuated inside the deep metal channel, making it difficult for them to penetrate and reach the electrical core chamber 6. The airflow carrying water vapor does not flow directly to the electrical core chamber 6, but first enters the dehumidification front chamber 5 located inside the heat dissipation module 4. The airflow flows through multiple baffle channels 51 with different cross-sectional areas, and the airflow velocity changes repeatedly. The water mist particles carried by the airflow continuously collide with the inner wall of the baffle channel 51. The hydrophilic coating area 52 on the windward side wall captures the water mist to form a water film. The water film flows to the superhydrophobic coating area 53 on the leeward side wall and then converges into liquid water droplets.

[0079] Liquid water droplets drip downwards from the wall of the baffle channel 51, landing on the inclined surfaces of the guide plates 56, 57, and 58 inside the dehumidification pre-compartment 5. The droplets flow along the inclined angle of the plates, and the guide ridge 561 constrains the flow path of the droplets. The droplets flow step by step to the tail end of the guide plate 58, and after being collected by the guide rib 59, they flow to the bottom guide channel 54. The guide ridge 541 inside the guide channel 54 guides the collected liquid water to the drain outlet 55, and the liquid water is directly discharged to the outside of the housing 1 through the drain outlet 55 that penetrates the wall panel 2 of the housing 1. The remaining gaseous water vapor in the airflow is further adsorbed by the moisture-absorbing material 50 arranged on the uppermost guide plates 56, 57, and 58. The dehumidified air then flows into the electrical core chamber 6 to dissipate heat and cool the internal components.

[0080] As the heat dissipation process continues, or as the ambient temperature decreases, the temperature inside the housing 1 drops below the phase change temperature. The shape memory alloy spring inside the drive mechanism 45 contracts, and the reset spring 451 pulls back, causing the first perforated grid plate 41 to slide in the opposite direction along the guide rail 43. The third perforated grid plate 49 simultaneously resets. The through holes 46 of the first perforated grid plate 41, the second perforated grid plate 42, and the third perforated grid plate 49 return to their misaligned state, and the ventilation channel is cut off again, preventing a large influx of external air into the housing 1. Under the residual heat inside the housing 1, the moisture-absorbing material 50 releases some of the previously absorbed moisture towards the heat dissipation module 4. The moisture can then escape through the heat dissipation window 3, achieving a certain degree of self-drying of the moisture-absorbing material 50, preparing it for the next moisture absorption operation. The equipment returns to a closed and protected working state, completing the entire workflow of temperature adaptive ventilation, moisture separation, and electromagnetic shielding.

[0081] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0082] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. An energy metering box with an adjustable heat dissipation module, comprising a box body (1), wherein a heat dissipation window (3) is provided on the wall panel (2) of the box body (1), and a heat dissipation module (4) is installed at the heat dissipation window (3), characterized in that: The heat dissipation module (4) includes a first perforated grid plate (41) and a second perforated grid plate (42) stacked sequentially along the normal direction of the wall panel (2). Both the first perforated grid plate (41) and the second perforated grid plate (42) have arrayed through holes (46). A guide rail (43) is provided inside the housing (1). The first perforated grid plate (41) is assembled on the guide rail (43). The second perforated grid plate (42) is fixed inside the housing (1). One end of the first perforated grid plate (41) is fixedly connected to the wall panel (2) through a drive mechanism (45), and the other end is fixedly connected to the inner wall of the accommodating space (21) of the wall panel (2) through a reset spring (451). The enclosure (1) is also equipped with a dehumidification pre-compartment (5) and an electrical core chamber (6). The dehumidification pre-compartment (5) is located between the heat dissipation module (4) and the electrical core chamber (6). The dehumidification pre-compartment (5) is equipped with a drain outlet (55).

2. The power metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: The driving mechanism (45) is a temperature driving component, which is a shape memory alloy spring. The preload of the reset spring (451) is less than the output thrust of the shape memory alloy spring after it reaches the phase change temperature, so that the shape memory alloy spring can overcome the tension of the reset spring (451) and drive the first perforated grid plate (41) to move when it stretches at high temperature.

3. The power metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: The through hole (46) includes a straight cylindrical section (461) and flared sections (462) located at both ends of the straight cylindrical section (461), wherein the diameter of the flared section (462) gradually increases in the direction away from the straight cylindrical section (461); The through holes (46) opened on the first perforated grid plate (41) and the second perforated grid plate (42) are arranged in a multi-row array. The through hole array alternately sets the first specification hole (463) and the second specification hole (464) along the row direction. The first specification hole (463) is arranged in odd-numbered rows and the second specification hole (464) is arranged in even-numbered rows. The aperture of the first specification hole (463) is the maximum diameter of the target shielding frequency band, and the aperture of the second specification hole (464) is smaller than the aperture of the first specification hole (463). The first specification hole (463) and the second specification hole (464) are staggered along the plate plane. When the first perforated grid plate (41) is translated relative to the second perforated grid plate (42), the first specification hole (463) and the second specification hole (464) are aligned to form an overlapping and connected ventilation channel.

4. The power metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: The guide rail (43) is provided with a dovetail groove (47), and the bottom of the first perforated grid plate (41) is provided with a dovetail slider (48) that matches the dovetail groove (47). The dovetail slider (48) is embedded in the dovetail groove (47) and slides along the extension direction of the dovetail groove (47). The dovetail groove (47) has several recessed grooves (471) on its inclined surface. A ball bearing (44) is fixedly mounted on the recessed groove (471) by several rotating shafts (441). A recessed groove (481) is provided on the inclined surface of the dovetail slider (48) in contact with the dovetail groove (47). The size of the recessed groove (481) matches that of the ball bearing (44). When the dovetail slider (48) slides along the extension direction of the dovetail groove (47), the ball bearing (44) in the recessed groove (471) rolls around the rotating shaft (441).

5. An energy metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: The dehumidification pre-filter (5) is provided with multiple sequentially connected baffle channels (51), and the flow cross-sectional areas of two adjacent baffle channels (51) are different.

6. An energy metering box with an adjustable heat dissipation module as described in claim 5, characterized in that: The windward side wall of the baffle channel (51) is provided with a hydrophilic coating area (52), and the leeward side wall of the baffle channel (51) is provided with a superhydrophobic coating area (53).

7. An energy metering box with an adjustable heat dissipation module as described in claim 6, characterized in that: The bottom of the dehumidification pre-compartment (5) is provided with a flow guide groove (54), and a flow guide protrusion (541) is provided on the flow guide groove (54). One end of the flow guide groove (54) is connected to the drain outlet (55), and the drain outlet (55) penetrates the wall panel (2) of the box body (1).

8. An energy metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: The heat dissipation module (4) also includes a third perforated grille (49), which is disposed on the side of the second perforated grille (42) away from the first perforated grille (41). The structure of the third perforated grille (49) is the same as that of the first perforated grille (41). At the position of the third perforated grille (49), the housing (1) is provided with a guide rail (43), a dovetail groove (47), a dovetail slider (48), a recess (471), and a ball bearing (44), which are the same as those of the first perforated grille (41). ), rotating shaft (441), sinker two (481), one end of the third perforated grid plate (49) is fixedly connected to the wall plate (2) through the driving mechanism (45), and the other end is fixedly connected to the inner wall of the accommodating space (21) of the wall plate (2) through the reset spring (451). The third perforated grid plate (49) has through holes (46) distributed on it. Under the drive of the driving mechanism (45), the through holes (46) on the third perforated grid plate (49) are aligned and connected with the through holes (46) on the second perforated grid plate (42).

9. An energy metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: In the initial state, the through holes (46) on the first perforated grid plate (41) and the second perforated grid plate (42) are misaligned. When the temperature is high, the driving mechanism (45) extends and drives the first perforated grid plate (41) to move relative to the second perforated grid plate (42) along the guide slide rail (43), so that the through holes (46) on the two are aligned and connected. The axial depth of the through channel formed after alignment is greater than the diameter of the through hole (46).

10. An energy metering box with an adjustable heat dissipation module as described in claim 1, characterized in that: Inside the dehumidification pre-cooling chamber (5), several sets of guide plates one (56), two (57), and three (58) that gradually tilt toward the heat dissipation module (4) are arranged along the width direction of the box body (1). The guide plates one (56), two (57), and three (58) are connected in sequence. The tail end of the guide plate three (58) is provided with a guide ridge (59). The top and bottom surfaces of the guide plates one (56), two (57), and three (58) are provided with several evenly distributed guide ridges two (561) to facilitate droplet guidance. The uppermost guide plates one (56), two (57), and three (58) are provided with moisture-absorbing material (50).

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