A metering low-voltage cable branch box
By combining various components within the enclosure, the cable is stably clamped and routed in a standardized manner, solving the problems of loose cables and poor contact in low-voltage cable branch boxes. This improves power supply stability and safety, and optimizes the efficiency and lifespan of the cable branch boxes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING HUALONG AOTAI ELECTRIC CO LTD
- Filing Date
- 2026-04-27
- Publication Date
- 2026-06-19
Smart Images
Figure CN122246630A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of cable power supply, specifically relating to a metering low-voltage cable branch box. Background Technology
[0002] Traditional metering low-voltage cable branch boxes often use bolt-plate clamping structures for cable clamping and limiting. Manual tightening can easily lead to uneven clamping force, making it difficult to establish stable contact. Cables are prone to loosening and displacement under external forces and vibrations, resulting in poor contact at the terminals and distorted metering data. Furthermore, there is no suitable arc-shaped limiting structure, which can easily damage the cable sheath during clamping. The operation is also cumbersome, requiring tools for disassembly and assembly, resulting in poor adaptability and making it difficult to meet the needs of rapid on-site construction and long-term stable cable fixation.
[0003] Patent CN222720900U discloses a low-voltage cable distribution box suitable for indoor use. This indoor low-voltage cable distribution box includes a cable distribution box with a fixed shell fixedly connected to its inner bottom surface. A sliding rod is slidably connected inside the fixed shell, with one end of the sliding rod outside the fixed shell positioned at an angle. A locking plate is fixedly connected to the other end of the sliding rod inside the fixed shell. This patent allows the locking plate to contact the cable line when the cabinet door is opened and closed, thus closing the cable distribution box and preventing humid air from entering and damaging the internal components. This protects the switches and other equipment inside the cable distribution box, ensuring normal operation and avoiding the need for repairs due to moisture damage.
[0004] However, during the use of the above-mentioned device, it is difficult to simultaneously prevent the cable connection from falling off when clamping the cable together, which makes it difficult to avoid the cable from getting tangled. This leads to unstable power supply of the device, which in turn affects the subsequent power supply efficiency and stability. Summary of the Invention
[0005] The purpose of this invention is to provide a metering low-voltage cable branch box to solve the problem of poor contact caused by the cable loosening after the cable is installed in the branch box.
[0006] To achieve the above objectives, the present invention provides a metering low-voltage cable branch box, comprising: a box body, an installation door on the box body, an insulating mounting frame installed inside the box body, an electric telescopic rod inside the box body, a movable frame fixedly connected to the telescopic end of the electric telescopic rod, a vertical rod fixedly connected to the top of the movable frame, a protective mechanism for cable protection provided on the inner wall of the vertical rod, a ventilation mechanism for ventilation and heat dissipation provided on the inner wall of the box body, a sliding groove rod fixedly connected to the inner wall of the box body, and a limit arc plate fixedly connected to the top of the movable frame. An elastic telescopic rod is fixedly connected to the inner wall, and a clamping plate is fixedly connected to the telescopic end of the elastic telescopic rod. A protrusion is installed on the vertical rod. A slider is slidably connected to the inner wall of the insulating mounting bracket. A fixed arc plate is fixedly connected to the left side of the slider, and a protrusion is fixedly connected to the right side of the slider. This can initially clamp and limit the cable, strengthen the cable terminals, ensure stable power supply connection, avoid loose terminals and poor contact, prevent overheating and burning problems caused by excessive contact resistance, ensure the continuity of metering and power supply, and standardize cable routing and optimize the layout inside the box.
[0007] In one possible implementation, the insulating mounting bracket is provided with a cable, the vertical rod is slidably connected to the inner wall of the insulating mounting bracket, the clamp is in contact with the cable, and the clamp is used to limit the cable. The clamp is located on the movement trajectory of the limiting arc plate, so that the cable line is standardized, avoids tangling, improves the installation and connection stability of the cable, prevents the cable connection from falling off, and further improves the power supply connection stability of the device.
[0008] In one possible implementation, the second protrusion is located on the movement trajectory of the first protrusion, and the first protrusion is used to squeeze and push the second protrusion to move. The cable is located on the movement trajectory of the fixed arc plate. A return spring is provided between the slider and the insulating mounting bracket. The upward movement of the moving bracket will synchronously drive the vertical rod to move. During the movement of the vertical rod, the vertical rod will drive the first protrusion to rise. After the first protrusion rises a certain distance, the arc surface of the first protrusion will contact the arc surface of the second protrusion.
[0009] In one possible implementation, the protective mechanism includes a fixed long plate, which is fixedly connected to the front of the vertical rod. An isolation plate is rotatably connected to the inner wall of the fixed long plate via a torsion spring. A retaining plate is fixedly connected to the inner wall of the enclosure. This prevents cables from falling off or becoming entangled due to other equipment inside the enclosure or external human factors, and provides direct protection for the cables, ensuring the smoothness and stability of subsequent power supply.
[0010] In one possible implementation, the protective mechanism further includes a sliding column slidably connected to the inner wall of the slider. A conductive arc plate is fixedly connected to the circumferential surface of the sliding column. A fixed sleeve is fixedly connected to the right side of the slider. An alarm is fixedly connected to the right side of the fixed sleeve. A conductive block is fixedly connected to the left side of the alarm. This mechanism can remind and warn operators, ensuring the safety of the device and improving its maintenance efficiency.
[0011] In one possible implementation, the locking plate contacts the isolation plate and is used to limit the isolation plate. A rebound spring is provided between the sliding column and the slider. The sliding column contacts the fixed arc plate, which is located on the movement trajectory of the conductive arc plate. The conductive block is located on the movement trajectory of the sliding column. The movement of the slider will drive the sliding column to move, which in turn will drive the conductive arc plate to move. At the same time, the slider will drive the fixed sleeve to move, which in turn will drive the warning device to move.
[0012] In one possible implementation, the ventilation mechanism includes a positive electrode strip fixedly connected to the front of the isolation plate, and a negative electrode strip fixedly connected to the inner wall of the fixed long plate. The positive and negative electrode strips can attract each other based on their magnetic attraction properties, which can ensure the protective stability of the isolation plate and enable the isolation plate to protect the cable installation and connection area for a long time.
[0013] In one possible implementation, the ventilation mechanism further includes a fixed plate fixedly connected to the inner wall of the housing. A second elastic telescopic rod is fixedly connected to the rear of the fixed plate, and a connecting plate is fixedly connected to the telescopic end of the second elastic telescopic rod. A movable column is fixedly connected to the front of the connecting plate, and rollers are rotatably connected to the inner wall of the movable column. A sealing plate is fixedly connected to the left side of the connecting plate, and a filter plate is fixedly connected to the inner wall of the housing. This configuration accelerates airflow within the device, cools the housing, prevents damage to equipment inside due to overheating, and extends the lifespan of the device.
[0014] In one possible implementation, the movable column contacts the fixed plate, the roller is located on the movement trajectory of the mounting door and the mounting door is used to push the roller to move, the sealing plate contacts the housing, the negative electrode bar is located on the movement trajectory of the positive electrode bar, the mounting door will squeeze and push the roller to move, the movement of the roller will drive the movable column to move, and the movement of the movable column will drive the connecting plate to move.
[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This metering low-voltage cable branch box, through the coordinated movement of the box body, installation door, insulating mounting frame, electric telescopic rod, moving frame, vertical rod, sliding rod, limiting arc plate, elastic telescopic rod one, clamping plate, protrusion one, slider, fixed arc plate, and protrusion two, can initially clamp and limit the cable, reinforce the cable terminals, ensure stable power supply connection, prevent loose terminals and poor contact, eliminate overheating and burning problems caused by excessive contact resistance, ensure the continuity of metering and power supply, standardize cable routing, optimize the internal layout of the box, make the cable lines standardized, avoid tangling, improve the stability of cable installation and connection, prevent cable connection from falling off, and further enhance the power supply connection stability of the device.
[0016] 2. This metering low-voltage cable branch box, through the coordinated movement of fixed long plates, isolation plates, clamping plates, sliding columns, conductive arc plates, fixing sleeves, warning devices, and conductive blocks, can prevent cables from falling off or becoming entangled after installation due to other equipment inside the box or external human factors. It can provide direct protection for the cables, ensure the smoothness and stability of subsequent power supply, remind and warn operators, ensure the safety of the device, and improve the maintenance efficiency of the device.
[0017] 3. This metering low-voltage cable branch box, through the coordinated movement of the positive and negative electrodes, fixed plate, elastic telescopic rod, connecting plate, moving column, roller, sealing plate, and filter plate, allows the positive and negative electrodes to attract each other based on their magnetic properties. This ensures the protective stability of the isolation plate, allows the isolation plate to protect the cable installation and connection area for a long time, accelerates the air circulation speed within the device, cools the inside of the box, prevents damage to the equipment inside the box due to excessive temperature, and extends the service life of the device. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the overall structure provided for an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the electric telescopic pole provided in the embodiments of this application; Figure 3 This is a schematic diagram of the mobile frame structure provided in an embodiment of this application; Figure 4 Provided for the embodiments of this application Figure 3 Enlarged view of the structure at point A in the middle; Figure 5 Provided for the embodiments of this application Figure 3 Enlarged view of the structure at point B in the middle; Figure 6 A schematic diagram of the protective mechanism provided in the embodiments of this application; Figure 7Provided for the embodiments of this application Figure 6 Enlarged view of the structure at point C; Figure 8 A schematic diagram of the ventilation mechanism provided in the embodiments of this application; Figure 9 This is a schematic diagram of the movable column structure provided in an embodiment of this application.
[0019] Explanation of key figure labels: 1. Box body; 2. Mounting door; 3. Insulating mounting bracket; 4. Electric telescopic rod; 5. Moving frame; 6. Vertical rod; 7. Protective mechanism; 8. Ventilation mechanism; 9. Sliding rod; 10. Limiting arc plate; 11. Elastic telescopic rod one; 12. Clamping plate; 13. Protrusion one; 14. Sliding block; 15. Fixed arc plate; 16. Protrusion two; 701. Fixed long plate; 702. Isolation plate; 703. Column clamping plate; 704. Sliding column; 705. Conductive arc plate; 706. Fixed sleeve; 707. Warning device; 708. Conductive block; 801. Positive electrode bar; 802. Negative electrode bar; 803. Fixed plate; 804. Elastic telescopic rod two; 805. Connecting plate; 806. Moving column; 807. Roller; 808. Sealing plate; 809. Filter plate. Detailed Implementation
[0020] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.
[0021] like Figures 1-9 As shown, one embodiment of the present invention is: a metering low-voltage cable branch box, comprising: a box body 1, an installation door 2 provided on the box body 1, an insulating mounting frame 3 installed inside the box body 1, an electric telescopic rod 4 provided inside the box body 1, a movable frame 5 fixedly connected to the telescopic end of the electric telescopic rod 4, a vertical rod 6 fixedly connected to the top of the movable frame 5, a protective mechanism 7 for cable protection provided on the inner wall of the vertical rod 6, a ventilation mechanism 8 for ventilation and heat dissipation provided on the inner wall of the box body 1, a sliding groove rod 9 fixedly connected to the inner wall of the box body 1, a limiting arc plate 10 fixedly connected to the top of the movable frame 5, an elastic telescopic rod 11 fixedly connected to the inner wall of the sliding groove rod 9, a clamping plate 12 fixedly connected to the telescopic end of the elastic telescopic rod 11, a protrusion 13 installed on the vertical rod 6, a slider 14 slidably connected to the inner wall of the insulating mounting frame 3, a fixed arc plate 15 fixedly connected to the left side of the slider 14, and a protrusion 16 fixedly connected to the right side of the slider 14; When the device is in use, the operator first connects and installs the cable. After the preparation is completed, the operator starts the electric telescopic rod 4 through the external controller. The telescopic end of the electric telescopic rod 4 will drive the moving frame 5 to move. The moving frame 5 can then rise stably on the inner wall of the sliding rod 9. The movement of the moving frame 5 will drive the limiting arc plate 10 to move. After the limiting arc plate 10 moves a certain distance, it will contact the clamping plate 12. After the limiting arc plate 10 contacts the clamping plate 12, the cable can be located in the hollow area created by the contact between the limiting arc plate 10 and the clamping plate 12. The cable can then be limited by the limiting arc plate 10 and the clamping plate 12, which can initially clamp and limit the cable, strengthen the cable terminal, ensure stable power supply connection, avoid loose terminals and poor contact, prevent overheating and burning problems caused by excessive contact resistance, ensure the continuity of metering and power supply, and standardize cable routing and optimize the layout inside the box. A cable is installed on the insulating mounting frame 3. The vertical rod 6 is slidably connected to the inner wall of the insulating mounting frame 3. The clamping plate 12 is in contact with the cable and is used to limit the cable. The clamping plate 12 is located on the movement trajectory of the limiting arc plate 10. The second protrusion 16 is located on the movement trajectory of the first protrusion 13 and is used to squeeze and push the second protrusion 16 to move. The cable is located on the movement trajectory of the fixed arc plate 15. A return spring is provided between the slider 14 and the insulating mounting frame 3. As the movable frame 5 rises, the vertical rod 6 moves synchronously with it. During this movement, the vertical rod 6 causes protrusion 13 to rise. After rising a certain distance, the arc surface of protrusion 13 contacts the arc surface of protrusion 2 16. Protrusion 13 continues to rise, and its arc surface presses against and pushes protrusion 2 16, allowing it to move. During this movement, protrusion 2 16 causes slider 14 to move, which in turn causes fixed arc plate 15 to move. After moving a certain distance, fixed arc plate 15 contacts the cable and clamps it near the connection point of the insulating mounting frame 3, ensuring proper cable routing, preventing tangling, improving cable connection stability, preventing cable disconnection, and further enhancing the power supply connection stability of the device. Overall working principle: It can initially clamp and limit the cable, strengthen the cable terminals, ensure stable power supply connection, avoid loose terminals and poor contact, eliminate overheating and burning problems caused by excessive contact resistance, ensure the continuity of metering and power supply, standardize cable routing, optimize the layout inside the box, and fix the cable near the connection of the insulating mounting bracket 3 by contacting the cable, so that the cable line is standardized and avoids tangling, which can improve the installation and connection stability of the cable, prevent the cable connection from falling off, and further improve the power supply connection stability of the device.
[0022] like Figures 1-9 As shown, based on the above embodiments, in another embodiment of the present invention, the protective mechanism 7 includes a fixed long plate 701, the fixed long plate 701 is fixedly connected to the front of the vertical rod 6, the inner wall of the fixed long plate 701 is rotatably connected to the isolation plate 702 by a torsion spring, and the inner wall of the box 1 is fixedly connected to the locking plate 703. When the device is in use, as the vertical rod 6 rises, it will drive the fixed long plate 701 to rise synchronously. The rise of the fixed long plate 701 will drive the isolation plate 702 to move and rise. After the isolation plate 702 rises a certain distance, the locking plate 703 will no longer be in contact with the isolation plate 702. The limiting effect of the locking plate 703 on the isolation plate 702 will be released. At this time, the isolation plate 702 will rotate and reset through its own torsion spring. After the isolation plate 702 rotates a certain angle, it can be located directly in front of the cable and isolate the cable from the outside world. This can prevent the cable from falling off or getting tangled due to other equipment in the box 1 or external human factors after installation. It can provide direct protection for the cable and ensure the smoothness and stability of subsequent power supply. The protective mechanism 7 also includes a sliding column 704, which is slidably connected to the inner wall of the slider 14. A conductive arc plate 705 is fixedly connected to the circumferential surface of the sliding column 704. A fixed sleeve 706 is fixedly connected to the right side of the slider 14. A warning device 707 is fixedly connected to the right side of the fixed sleeve 706. A conductive block 708 is fixedly connected to the left side of the warning device 707. A locking plate 703 contacts the isolation plate 702 and is used to limit the isolation plate 702. A rebound spring is provided between the sliding column 704 and the slider 14. The sliding column 704 contacts the fixed arc plate 15, which is located on the movement trajectory of the conductive arc plate 705. The conductive block 708 is located on the movement trajectory of the sliding column 704. During use, the movement of slider 14 causes slider 704 to move, which in turn causes conductive arc plate 705 to move. Simultaneously, slider 14 causes fixed sleeve 706 to move, which in turn causes alarm 707 to move. Alarm 707 then causes conductive block 708 to move. After moving a certain distance, conductive arc plate 705 comes into contact with the cable. At this point, conductive arc plate 705 is subjected to the reverse thrust of the cable, causing it to gradually approach slider 14 and move slider 704. After moving a certain distance, slider 704 comes into contact with conductive block 708. At this point, conductive arc plate 705 and conductive block 708 are in a current-connected state. If leakage occurs at the cable interface, the current can reach conductive block 708, which will activate, alerting the operator and ensuring the safety of the device and improving its maintenance efficiency. The ventilation mechanism 8 includes a positive electrode strip 801, which is fixedly connected to the front of the isolation plate 702, and a negative electrode strip 802 is fixedly connected to the inner wall of the fixed long plate 701. When the device is in use, during the reset and rotation of the isolation plate 702 by its own torsion spring, the isolation plate 702 will simultaneously drive the positive electrode bar 801 to rotate. After rotating a certain angle, the positive electrode bar 801 will come into contact with the negative electrode bar 802. The positive electrode bar 801 and the negative electrode bar 802 can attract each other based on their own magnetic attraction properties, which can ensure the protective stability of the isolation plate 702 and enable the isolation plate 702 to protect the cable installation and connection area for a long time. The ventilation mechanism 8 also includes a fixed plate 803, which is fixedly connected to the inner wall of the housing 1. A second elastic telescopic rod 804 is fixedly connected to the rear of the fixed plate 803. A connecting plate 805 is fixedly connected to the telescopic end of the second elastic telescopic rod 804. A moving column 806 is fixedly connected to the front of the connecting plate 805. A roller 807 is rotatably connected to the inner wall of the moving column 806. A sealing plate 808 is fixedly connected to the left side of the connecting plate 805. A filter plate 809 is fixedly connected to the inner wall of the housing 1. The moving column 806 is in contact with the fixed plate 803. The roller 807 is located on the movement trajectory of the mounting door 2, and the mounting door 2 is used to push the roller 807 to move. The sealing plate 808 is in contact with the housing 1. The negative electrode bar 802 is located on the movement trajectory of the positive electrode bar 801. When the device is in use, during the rotation of the mounting door 2, the mounting door 2 will come into contact with the roller 807. The mounting door 2 will squeeze and push the roller 807 to move. The movement of the roller 807 will drive the moving column 806 to move. The movement of the moving column 806 will drive the connecting plate 805 to move. The movement of the connecting plate 805 will drive the sealing plate 808 to move. After the sealing plate 808 moves a certain distance, the sealing plate 808 can open the ventilation opening of the box 1, which can accelerate the air circulation speed in the device, cool the inside of the box 1, prevent the equipment inside the box 1 from being damaged due to excessive temperature, and extend the service life of the device. Overall working principle: This system prevents cables from falling off or becoming entangled after installation, avoiding damage caused by other equipment within the enclosure or external human factors. It provides direct protection for the cables, ensuring smooth and stable power supply. It also provides warnings to operators, ensuring the safety of the device and improving maintenance efficiency. The positive electrode 801 and negative electrode 802 attract each other using their magnetic properties, ensuring the protective stability of the isolation plate 702. This allows the isolation plate 702 to protect the cable installation area for extended periods. It also accelerates airflow within the device, cooling the enclosure and preventing damage to equipment due to overheating, thus extending the device's lifespan.
[0023] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0024] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A metering low-voltage cable branch box, characterized in that, include: The enclosure (1) has an installation door (2) and an insulating mounting bracket (3) installed inside. An electric telescopic rod (4) is installed inside the enclosure (1). A movable frame (5) is fixedly connected to the telescopic end of the electric telescopic rod (4). A vertical rod (6) is fixedly connected to the top of the movable frame (5). A protective mechanism (7) for cable protection is installed on the inner wall of the vertical rod (6). A ventilation mechanism (8) for ventilation and heat dissipation is installed on the inner wall of the enclosure (1). The inner wall of the enclosure (1) is fixedly connected to... A sliding rod (9) is connected to the top of the movable frame (5), a limiting arc plate (10) is fixedly connected to the top of the sliding frame (5), an elastic telescopic rod (11) is fixedly connected to the inner wall of the sliding rod (9), a clamping plate (12) is fixedly connected to the telescopic end of the elastic telescopic rod (11), a protrusion (13) is installed on the vertical rod (6), a slider (14) is slidably connected to the inner wall of the insulating mounting frame (3), a fixing arc plate (15) is fixedly connected to the left side of the slider (14), and a protrusion (16) is fixedly connected to the right side of the slider (14).
2. The metering low-voltage cable branch box according to claim 1, characterized in that, The insulating mounting bracket (3) is provided with a cable, the vertical rod (6) is slidably connected to the inner wall of the insulating mounting bracket (3), the clamp (12) is in contact with the cable, and the clamp (12) is used to limit the cable. The clamp (12) is located on the movement trajectory of the limiting arc plate (10).
3. A metering low-voltage cable branch box according to claim 2, characterized in that, The second protrusion (16) is located on the movement trajectory of the first protrusion (13), and the first protrusion (13) is used to squeeze and push the second protrusion (16) to move. The cable is located on the movement trajectory of the fixed arc plate (15), and a reset spring is provided between the slider (14) and the insulating mounting bracket (3).
4. A metering low-voltage cable branch box according to claim 3, characterized in that, The protective mechanism (7) includes a fixed long plate (701), which is fixedly connected to the front of the vertical rod (6). The inner wall of the fixed long plate (701) is rotatably connected to an isolation plate (702) via a torsion spring. The inner wall of the box (1) is fixedly connected to a locking plate (703).
5. A metering low-voltage cable branch box according to claim 4, characterized in that, The protective mechanism (7) also includes a sliding column (704), which is slidably connected to the inner wall of the slider (14). A conductive arc plate (705) is fixedly connected to the circumferential surface of the sliding column (704). A fixed sleeve (706) is fixedly connected to the right side of the slider (14). A warning device (707) is fixedly connected to the right side of the fixed sleeve (706). A conductive block (708) is fixedly connected to the left side of the warning device (707).
6. A metering low-voltage cable branch box according to claim 5, characterized in that, The locking plate (703) contacts the isolation plate (702), and the locking plate (703) is used to limit the isolation plate (702). A rebound spring is provided between the sliding column (704) and the slider (14). The sliding column (704) contacts the fixed arc plate (15). The fixed arc plate (15) is located on the movement trajectory of the conductive arc plate (705). The conductive block (708) is located on the movement trajectory of the sliding column (704).
7. A metering low-voltage cable branch box according to claim 6, characterized in that, The ventilation mechanism (8) includes a positive electrode strip (801), which is fixedly connected to the front of the isolation plate (702), and a negative electrode strip (802) is fixedly connected to the inner wall of the fixed long plate (701).
8. A metering low-voltage cable branch box according to claim 7, characterized in that, The ventilation mechanism (8) also includes a fixing plate (803), which is fixedly connected to the inner wall of the box (1). A second elastic telescopic rod (804) is fixedly connected to the rear of the fixing plate (803). A connecting plate (805) is fixedly connected to the telescopic end of the second elastic telescopic rod (804). A moving column (806) is fixedly connected to the front of the connecting plate (805). A roller (807) is rotatably connected to the inner wall of the moving column (806). A sealing plate (808) is fixedly connected to the left side of the connecting plate (805). A filter plate (809) is fixedly connected to the inner wall of the box (1).
9. A metering low-voltage cable branch box according to claim 8, characterized in that, The movable column (806) contacts the fixed plate (803), the roller (807) is located on the movement trajectory of the mounting door (2), and the mounting door (2) is used to push the roller (807) to move. The sealing plate (808) contacts the box (1), and the negative electrode bar (802) is located on the movement trajectory of the positive electrode bar (801).