Outdoor low-voltage cable branch box
Patent Information
- Application Number
- CN202611368373.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-04
- Publication Date
- 2026-10-30
AI Technical Summary
现有技术中通常仅在电缆孔处安装简易橡胶圈，当电缆受到外力拉扯或风吹晃动时，橡胶圈与电缆之间容易产生间隙，外部水分极易沿电缆表面渗入箱体内部
[0016]因此，本发明提供的一种户外低压电缆分支箱，具有以下有益效果：本发明的箱门一侧与箱体一侧卡接配合并转动连接，箱体的门框边缘沿除转动连接侧外的其余三侧边缘连续设置密封条，配合锁紧机构将箱门锁紧于箱体上，使箱门的内侧边缘压紧密封条，有效防止雨水从箱门缝隙渗入箱体内部，提高了分支箱在户外恶劣天气条件下的防护能力。
Smart Images
Figure CN123018680A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cable branch box technology, and particularly to an outdoor low-voltage cable branch box. Background Technology
[0002] Cable distribution boxes, as the main equipment for cable branching or switching, are widely used in power distribution networks. With the continuous development of cable-based power distribution networks, cable distribution boxes have become the final-level equipment in power distribution systems. Outdoor cable distribution boxes are exposed to wind, sun, and rain for extended periods, making them susceptible to corrosion and damage from rainwater and humid air entering the box, significantly increasing maintenance and repair costs.
[0003] The existing cable distribution boxes have insufficient sealing performance at the door. During strong winds and heavy rain, rainwater can easily enter the box through the gap between the box body and the door, causing short circuits and other malfunctions, affecting normal use. The bottom of the cable distribution box usually has cable holes for cables to pass through. When water accumulates in the cable trench, the area around the cable holes remains damp or even submerged. Current technology typically only installs simple rubber rings at the cable holes. When the cable is pulled or shaken by the wind, gaps can easily form between the rubber ring and the cable, allowing external moisture to easily seep into the box along the cable surface.
[0004] Therefore, there is an urgent need for a low-voltage cable branch box that combines good door sealing performance, cable inlet sealing performance, and top waterproof performance to solve the problems existing in the above-mentioned prior art. Summary of the Invention
[0005] The purpose of this invention is to provide an outdoor low-voltage cable branch box to solve the problems mentioned in the background art.
[0006] To achieve the above objectives, the present invention provides an outdoor low-voltage cable branch box, including a box body, a box door disposed on the front and rear sides of the box body, a bottom plate fixedly disposed on the bottom of the box body, and a box top fixedly disposed on the top of the box body. The box body is also provided with vertical mounting columns and horizontal mounting rails. The vertical mounting columns are fixed to the inner walls on both sides of the box body, and the horizontal mounting rails are detachably and fixedly assembled on the vertical mounting columns. One side of the cabinet door is engaged with and rotatably connected to one side of the cabinet body, and a locking mechanism is provided between the cabinet door and the other side of the cabinet body; The base plate is also provided with a cable hole for the cable to pass through, and a cable inlet sealing structure is provided at the cable hole.
[0007] Preferably, a raised rotating shaft is provided on the side of the box door that is rotatably connected to the box body, and a rotating groove adapted to the raised rotating shaft is provided on the corresponding side of the box body. The raised rotating shaft is engaged with the rotating groove and rotatably connected.
[0008] Preferably, a sealing strip is provided around the edge of the door frame of the box, and the sealing strip is continuously provided along the other three edges of the box except for the rotating connection side; The locking structure is used to lock the box door onto the box body and to press the inner edge of the box door against the sealing strip.
[0009] Preferably, the locking mechanism includes a latch and a lock cylinder. The latch is located on the inside of the door, and the lock cylinder is located on the door. The lock cylinder is connected to the latch in a driving manner. By inserting a key into the lock cylinder and rotating it, the latch is driven to extend and engage with the door frame of the box.
[0010] Preferably, the top of the box is a waterproof cover, which is fixedly installed on the top of the box body. The waterproof cover is ridge-shaped, and the top surface of the waterproof cover extends downward symmetrically from the middle to both sides. The tilt angle of the waterproof cover is not less than 3°, and the edge of the waterproof cover extends outward beyond the side wall of the box body.
[0011] Preferably, the vertical mounting column has multiple mounting holes spaced apart along its height, and the horizontal mounting guide rail is bolted to the vertical mounting column through the mounting holes. The mounting height of the horizontal mounting guide rail is adjusted by selecting mounting holes of different heights.
[0012] Preferably, the inner surface of the side wall of the box is covered with an anti-condensation layer, the side wall of the box is provided with a ventilation opening, a dust filter is provided at the ventilation opening, and a downwardly sloping water-retaining eave is provided on the outside of the ventilation opening, with the ventilation opening located below the water-retaining eave; A waterproof platform is provided at the bottom of the base plate, and the cable hole is located above the waterproof platform.
[0013] Preferably, the cable inlet sealing structure includes a base, an inner sealing plate, an outer sealing plate, an inner pressing plate, and an outer pressing plate. Multiple bases are fixedly installed on the bottom plate, and each base is provided with a through hole extending along the axis. The inner sealing plate is fixedly installed on the inner side of the base, and a first through hole for the cable to pass through is opened in the center of the inner sealing plate; the outer sealing plate is fixedly installed on the top outer side of the base, and a second through hole for the cable to pass through is opened in the center of the outer sealing plate. An inner sealing ring and an outer sealing ring are respectively provided between the inner sealing plate and the outer wall of the cable, and between the outer sealing plate and the outer wall of the cable; The inner clamping plate is used to press the inner sealing ring, causing the inner sealing ring to compress and deform and thus grip the outer wall of the cable. The outer clamping plate is used to press the outer sealing ring, causing the outer sealing ring to compress and deform and thus grip the outer wall of the cable.
[0014] Preferably, the inner bore walls of the inner sealing plate and the outer sealing plate are tapered surfaces, and the inner sealing ring and the outer sealing ring are respectively placed in the tapered annular gaps between the inner bore wall of the inner sealing plate, the inner bore wall of the outer sealing plate, and the outer wall of the cable.
[0015] Preferably, a first sealing gasket is provided between the base and the bottom plate, and a second sealing gasket is provided between the outer sealing plate and the base. The base, the inner sealing plate, the outer sealing plate, and the outer wall of the cable together form a sealed cavity.
[0016] Therefore, the outdoor low-voltage cable branch box provided by the present invention has the following beneficial effects: the box door is engaged and rotatably connected to the box body on one side, and a sealing strip is continuously provided along the three sides of the box body's door frame edge except for the rotatably connected side. The locking mechanism locks the box door to the box body, so that the inner edge of the box door presses the sealing strip tightly, effectively preventing rainwater from seeping into the box body from the gaps in the box door, and improving the protection capability of the branch box under harsh outdoor weather conditions.
[0017] The cable inlet sealing structure of this invention adopts a sealing design consisting of a base, an inner sealing plate, an outer sealing plate, an inner sealing ring, and an outer sealing ring. The inner walls of the inner and outer sealing plates are tapered, forming a tapered annular gap with the outer wall of the cable. The sealing ring is placed within this gap, and the sealing ring is compressed and deformed by a pressing plate to grip the outer wall of the cable. This effectively seals the gap between the cable and the mounting hole, preventing external humid gas from entering the housing through the cable hole.
[0018] The waterproof top cover of this invention is designed in a ridge shape, with the top surface extending symmetrically downwards from the center to both sides at an angle of not less than 3°. This facilitates the rapid diversion and drainage of rainwater to both sides, preventing water accumulation on the top. The edges of the waterproof top cover extend outwards beyond the side walls of the enclosure, effectively preventing rainwater from washing away the gaps in the door as it flows down the outer wall of the enclosure, thus reducing the risk of rainwater seeping in through the door gaps. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the overall structure of an outdoor low-voltage cable branch box according to an embodiment of the present invention; Figure 2 This is a left view of an outdoor low-voltage cable branch box according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the overall structure of an outdoor low-voltage cable branch box from a second perspective in an embodiment of the present invention; Figure 4This is a schematic diagram of the internal structure of an outdoor low-voltage cable branch box according to an embodiment of the present invention; Figure 5 This is an exploded view of the door frame of the box door and the box body in an embodiment of the present invention; Figure 6 This is a top view of the connection state between the box door and the door frame of the box body in an embodiment of the present invention; Figure 7 for Figure 6 A magnified view of a section at point A in the middle; Figure 8 This is a schematic diagram of the cable inlet sealing structure in an embodiment of the present invention; Figure Labels 1. Enclosure; 2. Enclosure door; 3. Base plate; 31. Waterproof platform; 32. Cable hole; 4. Enclosure top; 5. Vertical mounting column; 51. Mounting hole; 6. Horizontal mounting guide rail; 7. Locking mechanism; 71. Lock tongue; 72. Lock cylinder; 8. Sealing strip; 9. Anti-condensation layer; 10. Ventilation opening; 101. Dust filter; 102. Water barrier; 11. Rotating groove; 12. Base; 121. Through hole; 13. Inner sealing plate; 131. First through hole; 141. Second through hole; 14. Outer sealing plate; 15. Inner pressure plate; 16. Outer pressure plate; 17. First sealing gasket; 18. Inner sealing ring; 19. Outer sealing ring; 20. Second sealing gasket; 21. Raised rotating shaft; 22. Sealing cavity; 23. Cable inlet sealing structure; 24. Cable. Detailed Implementation
[0020] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.
[0021] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0023] Example like Figure 1-4 As shown, this invention discloses an outdoor low-voltage cable distribution box, comprising a box body 1, box doors 2 disposed on the front and rear sides of the box body 1, a base plate 3 fixedly disposed at the bottom of the box body 1, and a box top 4 fixedly disposed at the top of the box body 1. The box body 1 has vertical mounting columns 5 and horizontal mounting rails 6 inside. The vertical mounting columns 5 are fixed to the inner walls of both sides of the box body 1, and the horizontal mounting rails 6 are detachably and fixedly mounted on the vertical mounting columns 5. The box body 1 has an internal space for accommodating power distribution modules and connecting cables. The box body 1 has excellent weather resistance, insulation, and mechanical strength, making it suitable for long-term outdoor use.
[0024] One side of the door 2 engages and rotates with one side of the body 1. A protruding pivot 21 is provided on the side of the door 2 that rotates with the body 1, and a corresponding rotating groove 11 is provided on the side of the body 1 that matches the protruding pivot 21. The protruding pivot 21 engages and rotates with the rotating groove 11. A locking mechanism 7 is provided between the other side of the door 2 and the body 1. The locking mechanism 7 is used to lock the door 2 onto the body 1 and to press the inner edge of the door 2 against the sealing strip 8.
[0025] like Figure 5-7 As shown, a sealing strip 8 is provided around the edge of the door frame of the enclosure 1. The sealing strip 8 is continuously provided along the three edges of the enclosure 1, excluding the rotating connection side. When the locking mechanism 7 locks the door 2, the inner edge of the door 2 presses against the sealing strip 8, causing the sealing strip 8 to undergo elastic compression deformation and fill the gap between the door 2 and the door frame of the enclosure 1. The sealing strip 8 is preferably made of EPDM rubber, which has excellent ozone resistance, UV resistance, and weather resistance.
[0026] The locking mechanism 7 includes a latch 71 and a lock cylinder 72. The latch 71 is located on the inside of the door 2, and the lock cylinder 72 is located on the door 2. The lock cylinder 72 and the latch 71 are connected in a driving manner. By inserting a key into the lock cylinder 72 and turning it, the latch 71 is driven to extend and engage with the corresponding latch hole on the door frame of the box 1, thus locking the door 2 onto the box 1. When the locking mechanism 7 is locked, the inner edge of the door 2 simultaneously presses against the sealing strip 8, achieving a sealing effect upon locking.
[0027] The top 4 of the container is a waterproof cover, which is fixedly installed on the top of the container body 1. The waterproof cover is designed in a ridge shape, with its top surface symmetrically sloping downwards from the center to both sides at an angle of not less than 3°. The ridge-shaped top surface design allows rainwater to quickly drain away along the left and right sides after falling on the cover, preventing water accumulation on the top. The edge of the waterproof cover extends outwards beyond the side wall of the container body 1. This extended structure ensures that rainwater dripping along the edge of the cover falls onto the outside of the container body 1, rather than flowing down the side wall of the container body 1, effectively preventing rainwater from washing away the gap between the door 2 and the container body 1, and reducing the risk of water seepage through the door gap.
[0028] The vertical mounting column 5 has multiple mounting holes 51 spaced apart along its height. The horizontal mounting rail 6 is bolted to the vertical mounting column 5 through the mounting holes 51. The installation height of the horizontal mounting rail 6 is adjusted by selecting mounting holes 51 at different heights. During on-site construction, the horizontal mounting rail 6 can be fixed at the appropriate height of the mounting holes 51 according to the size of the power distribution module and the wiring position requirements. Then, the power distribution module (such as circuit breaker, fuse, terminal block, etc.) is installed on the horizontal mounting rail 6. This adjustable installation structure allows for flexible and adjustable internal space layout of the branch box, suitable for power distribution modules of different specifications.
[0029] The inner surface of the side wall of the enclosure 1 is covered with an anti-condensation layer 9, which is electrical insulation cotton. A ventilation opening 10 is provided on the side wall of the enclosure 1, and a dust filter 101 is installed at the ventilation opening 10 to reduce dust entering the interior of the enclosure 1. A downwardly sloping water-retaining eave 102 is provided on the outer side of the ventilation opening 10, and the ventilation opening 10 is located below the water-retaining eave 102. The downwardly sloping water-retaining eave 102 can effectively prevent rainwater from splashing into the ventilation opening 10 from above, while ensuring the air pressure balance inside and outside the enclosure 1.
[0030] A waterproof platform 31 is provided at the bottom of the base plate 3, and a cable hole 32 is opened above the waterproof platform 31.
[0031] like Figure 8 As shown, the cable inlet sealing structure 23 includes a base 12, an inner sealing plate 13, an outer sealing plate 14, an inner clamping plate 15, and an outer clamping plate 16. Multiple bases 12 are fixedly installed on the base plate 3, and each base 12 has a through hole 121 extending along its axis. The number and position of the bases 12 correspond to the cable holes 32 on the base plate 3, with one base 12 located at each cable hole 32. A first sealing gasket 17 is provided between the bottom of the base 12 and the base plate 3. The first sealing gasket 17 seals the contact surface between the base 12 and the base plate 3, preventing moisture from seeping in from the mating surface of the base 12 and the base plate 3.
[0032] The inner sealing plate 13 is fixedly installed on the inner side of the base 12, and a first through hole 131 for the cable 24 to pass through is opened in the center of the inner sealing plate 13. The outer sealing plate 14 is fixedly installed on the top outer side of the base 12, and a second through hole 141 for the cable 24 to pass through is opened in the center of the outer sealing plate 14. The inner sealing plate 13 and the outer sealing plate 14 respectively seal the through hole 121 of the base 12 from the inside and the outside, forming the main body of the sealing structure together with the base 12.
[0033] An inner sealing ring 18 is provided between the inner sealing plate 13 and the outer wall of the cable 24, and an outer sealing ring 19 is provided between the outer sealing plate 14 and the outer wall of the cable 24. An inner clamping plate 15 is used to clamp the inner sealing ring 18, causing it to compress and deform, thus gripping the outer wall of the cable 24. An outer clamping plate 16 is used to clamp the outer sealing ring 19, causing it to compress and deform, thus gripping the outer wall of the cable 24. Specifically, the inner walls of the inner sealing plate 13 and the outer sealing plate 14 are tapered surfaces, and the inner sealing ring 18 and the outer sealing ring 19 are respectively placed within the tapered annular gaps between the inner wall of the inner sealing plate 13, the inner wall of the outer sealing plate 14, and the outer wall of the cable 24. When the inner clamping plate 15 and the outer clamping plate 16 clamp the inner sealing ring 18 and the outer sealing ring 19 axially, respectively, the tapered annular gaps force the sealing rings to expand radially while compressing axially, thereby tightly gripping the outer wall of the cable 24.
[0034] A second sealing gasket 20 is provided between the outer sealing plate 14 and the base 12. The second sealing gasket 20 is used to seal the contact surface between the outer sealing plate 14 and the base 12. The base 12, the inner sealing plate 13, the outer sealing plate 14 and the outer wall of the cable 24 together form a sealed cavity 22. Through the sealing rings on the inner and outer sides and the sealing gaskets at each joint surface, multiple seals are achieved at the inlet of the cable 24.
[0035] The installation process of an outdoor low-voltage cable branch box according to the present invention is as follows: First, fix the enclosure 1 in the preset position, so that the waterproof platform 31 at the bottom of the base plate 3 is placed stably on the ground or base. On-site construction personnel fix the horizontal mounting rail 6 to the mounting hole 51 at an appropriate height on the vertical mounting column 5 with bolts according to the size of the power distribution module and the wiring requirements. Then, the power distribution module is installed on the horizontal mounting rail 6.
[0036] Next, the cable 24 is inserted. The cable 24 is inserted through the cable hole 32 on the waterproof platform 31 at the bottom of the base plate 3, and then sequentially passes through the through hole 121 of the base 12, the second through hole 141 of the outer sealing plate 14, the outer sealing ring 19, the first through hole 131 of the inner sealing plate 13, and the inner sealing ring 18, entering the interior of the enclosure 1. Then, the end of the cable 24 is electrically connected to the wiring terminals of the power distribution module.
[0037] Next, the cable 24 inlet sealing operation is performed. The inner sealing ring 18 is placed within the conical annular gap between the conical inner wall of the inner sealing plate 13 and the outer wall of the cable 24. The inner clamping plate 15 is installed on the inner sealing plate 13 and locked with fasteners, causing the inner clamping plate 15 to axially press against the inner sealing ring 18. The inner sealing ring 18 expands radially under the constraint of the conical annular gap, tightly gripping the outer wall of the cable 24. Similarly, the outer sealing ring 19 is placed within the conical annular gap between the conical inner wall of the outer sealing plate 14 and the outer wall of the cable 24. The outer clamping plate 16 is installed on the outer sealing plate 14 and locked with fasteners, causing the outer clamping plate 16 to axially press against the outer sealing ring 19. The outer sealing ring 19 expands radially, tightly gripping the outer wall of the cable 24.
[0038] Finally, by inserting the key into the lock cylinder 72 and turning it, the bolt 71 is driven to extend and engage with the bolt hole on the door frame of the box 1, locking the door 2 onto the box 1. Simultaneously, as the door 2 is locked, the inner edge of the door 2 presses against the sealing strip 8 on three sides. The sealing strip 8 undergoes elastic compression deformation, filling the gap between the door 2 and the door frame of the box 1, forming a complete door seal.
[0039] Therefore, the present invention improves the waterproof sealing performance and installation flexibility of the low-voltage cable branch box through the above-mentioned three-sided sealing structure of the box door, the multi-sealing structure of the cable inlet, the ridge-type waterproof top cover, and the adjustable internal installation structure.
[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.
Claims
1. An outdoor low-voltage cable branch box, characterized in that: The container includes a box body, boxes with doors on the front and rear sides of the box body, a bottom plate fixedly installed at the bottom of the box body, and a box top fixedly installed at the top of the box body. The box body also has vertical mounting columns and horizontal mounting rails inside. The vertical mounting columns are fixed to the inner walls on both sides of the box body, and the horizontal mounting rails are detachably and fixedly assembled to the vertical mounting columns. One side of the cabinet door is engaged with and rotatably connected to one side of the cabinet body, and a locking mechanism is provided between the cabinet door and the other side of the cabinet body; The base plate is also provided with a cable hole for the cable to pass through, and a cable inlet sealing structure is provided at the cable hole.
2. The outdoor low-voltage cable branch box according to claim 1, characterized in that: A raised pivot is provided on one side of the box door that is rotatably connected to the box body, and a rotating groove adapted to the raised pivot is provided on the corresponding side of the box body. The raised pivot is engaged with the rotating groove and rotatably connected.
3. An outdoor low-voltage cable branch box according to claim 2, characterized in that: A sealing strip is provided around the edge of the door frame of the box, and the sealing strip is continuously provided along the other three edges of the box except for the rotating connection side; The locking structure is used to lock the box door onto the box body and to press the inner edge of the box door against the sealing strip.
4. An outdoor low-voltage cable branch box according to claim 3, characterized in that: The locking mechanism includes a latch and a lock cylinder. The latch is located on the inside of the door, and the lock cylinder is located on the door. The lock cylinder is connected to the latch in a driving manner. By inserting a key into the lock cylinder and turning it, the latch is driven to extend and engage with the door frame of the box.
5. An outdoor low-voltage cable branch box according to claim 4, characterized in that: The top of the box is a waterproof cover, which is fixedly installed on the top of the box body. The waterproof cover is ridge-shaped, and the top surface of the waterproof cover extends downward symmetrically from the middle to both sides. The tilt angle of the waterproof cover is not less than 3°, and the edge of the waterproof cover extends outward beyond the side wall of the box body.
6. An outdoor low-voltage cable branch box according to claim 5, characterized in that: The vertical mounting column has multiple mounting holes spaced apart along its height. The horizontal mounting guide rail is bolted to the vertical mounting column through the mounting holes. The mounting height of the horizontal mounting guide rail is adjusted by selecting mounting holes of different heights.
7. An outdoor low-voltage cable branch box according to claim 6, characterized in that: The inner surface of the side wall of the box is covered with an anti-condensation layer. Ventilation openings are provided on the side wall of the box. Dust filters are installed at the ventilation openings. A downward-sloping water-retaining eave is provided on the outside of the ventilation openings. The ventilation openings are located below the water-retaining eaves. A waterproof platform is provided at the bottom of the base plate, and the cable hole is located above the waterproof platform.
8. An outdoor low-voltage cable branch box according to claim 7, characterized in that: The cable inlet sealing structure includes a base, an inner sealing plate, an outer sealing plate, an inner pressing plate, and an outer pressing plate. Multiple bases are fixedly installed on the bottom plate, and each base is provided with a through hole extending along the axis. The inner sealing plate is fixedly installed on the inner side of the base, and a first through hole for the cable to pass through is opened in the center of the inner sealing plate; the outer sealing plate is fixedly installed on the top outer side of the base, and a second through hole for the cable to pass through is opened in the center of the outer sealing plate. An inner sealing ring and an outer sealing ring are respectively provided between the inner sealing plate and the outer wall of the cable, and between the outer sealing plate and the outer wall of the cable; The inner clamping plate is used to press the inner sealing ring, causing the inner sealing ring to compress and deform and thus grip the outer wall of the cable. The outer clamping plate is used to press the outer sealing ring, causing the outer sealing ring to compress and deform and thus grip the outer wall of the cable.
9. An outdoor low-voltage cable branch box according to claim 8, characterized in that: The inner walls of the inner and outer sealing plates are tapered surfaces, and the inner and outer sealing rings are respectively placed in the tapered annular gaps between the inner wall of the inner sealing plate, the inner wall of the outer sealing plate, and the outer wall of the cable.
10. An outdoor low-voltage cable branch box according to claim 9, characterized in that: A first sealing gasket is provided between the base and the bottom plate, and a second sealing gasket is provided between the outer sealing plate and the base. The base, the inner sealing plate, the outer sealing plate, and the outer wall of the cable together form a sealed cavity.