Cable branch box with hierarchical pressure relief protection structure

Abstract

This invention belongs to the field of cable branch box technology and discloses a cable branch box with a graded pressure relief protection structure. It includes a cable branch box, a primary box temperature sensing component, a secondary box pressure sensing component, a pressure relief chamber assembly, a pressure relief valve plate assembly, and a pressure relief drive assembly. The primary box temperature sensing component physically senses abnormal temperature rises inside the box through the thermal expansion of thermosensitive paraffin and triggers one side of the pressure relief chamber for primary pressure relief. The secondary box pressure sensing component senses pressure changes inside the box through a piston and triggers the other side of the pressure relief chamber for secondary pressure relief. The pressure relief drive assembly converts the linear displacement of the sensing component into rotational motion, causing multiple pressure relief valve plates to expand outwards synchronously, thereby quickly releasing the blockage of the pressure relief port. This invention can implement graded automatic pressure relief based on abnormal temperature and pressure rises inside the box without external electrical control, improving the timeliness of the cable branch box's pressure relief response and the reliability of its safety protection.

Description

Technical Field

[0001] This invention belongs to the technical field of cable branch boxes, and specifically relates to a cable branch box with a graded pressure relief protection structure. Background Technology

[0002] Cable distribution boxes, as branching and switching devices in cable lines, are usually installed outdoors or in power distribution locations. They contain electrical components such as cable joints, busbars, and switches. During long-term operation, factors such as increased contact resistance, loose joints, insulation aging, and line overload can cause abnormal heating inside the box. When the heat cannot be dissipated in time, it will not only accelerate the aging of the insulation material, but may also cause arcing faults and cause the temperature and pressure inside the box to continue to rise.

[0003] Existing cable distribution boxes typically employ a single pressure triggering method for their pressure relief structure. The pressure relief port only opens when the internal pressure of the box reaches a certain level, making it difficult to relieve pressure and dissipate heat in advance during abnormal temperature rises. When an electric arc flash causes the internal pressure of the box to rise rapidly, the single pressure relief structure may also have problems such as untimely triggering, insufficient pressure relief area, and slow opening speed of the pressure relief port. This can easily lead to box deformation, door opening, or further expansion of the malfunction, affecting the safety of surrounding equipment and personnel.

[0004] In addition, some pressure relief devices rely on temperature sensors, pressure sensors, motors or controllers for detection and driving. When the cable branch box experiences a power outage, electrical component damage or arc interference, the relevant detection and driving structures may not function properly, reducing the reliability of pressure relief protection. Therefore, it is necessary to provide a graded pressure relief protection structure that can respond separately to abnormal temperature rise and pressure surge inside the box and can quickly open the pressure relief port. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention provides a cable branch box with a graded pressure relief protection structure, which solves the problems of existing cable branch boxes having a single pressure relief triggering method, difficulty in graded response to abnormal temperature rise and pressure surge inside the box, slow opening speed of the pressure relief port, and high dependence on external electrical control system.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a cable branch box with a graded pressure relief protection structure, comprising a cable branch box, and further comprising: A primary temperature sensing component is installed on one side of the cable branch box. A secondary box pressure sensing component is installed on the other side of the cable branch box. Two sets of pressure relief chamber assemblies are provided. One set of pressure relief chamber assemblies is installed on the side of the cable branch box near the first-stage box temperature sensing assembly, and the other set of pressure relief chamber assemblies is installed on the side of the cable branch box near the second-stage box pressure sensing assembly. Multiple sets of pressure relief valve plate assemblies are slidably disposed at the pressure relief port of the pressure relief chamber assembly, for synchronously closing and sealing the pressure relief port of the pressure relief chamber assembly; A pressure relief drive assembly is rotatably disposed at the pressure relief port of the pressure relief chamber assembly; The primary temperature sensing component physically senses the high temperature inside the cable branch box, causing the primary temperature sensing component to automatically trigger the pressure relief drive component to drive multiple pressure relief valve plate components to release the blockage of the pressure relief chamber component, thereby realizing the primary temperature control triggered pressure relief of the pressure relief chamber component on one side of the primary temperature sensing component. The secondary pressure sensing component physically senses the pressure inside the cable branch box, causing it to automatically trigger the pressure relief drive component to drive multiple pressure relief valve plate components to release the blockage of the pressure relief chamber component's pressure relief port, thereby realizing the automatic triggering of pressure relief of the secondary pressure of the pressure relief chamber component on one side of the secondary pressure sensing component.

[0007] Preferably, the primary chamber temperature sensing component includes a first sensing chamber, a seat chamber fixedly disposed at one end of the first sensing chamber, a heat-conducting plate disposed inside the seat chamber, a first piston slidably disposed inside the first sensing chamber, a first slide rod fixedly disposed on the first piston, a first cross arm fixedly disposed at the end of the first slide rod away from the first piston, a first drive ring fixedly disposed at the end of the first cross arm away from the first slide rod, a first drive protrusion fixedly disposed on the inner wall of the first drive ring, and a first sliding hole opened on the edge of the first drive ring, and a first top pressure spring sleeved on the first slide rod; The outer wall of the middle part of the first sensing chamber is fixedly installed on the box body on one side of the cable branch box. The seat and heat conduction plate are located inside the cable branch box, and the first cross arm and the first drive ring are located outside the cable branch box body. The first slide rod slides through one end of the first sensing chamber, and the two ends of the first top pressure spring abut against the first piston and the inner wall of the first sensing chamber, respectively.

[0008] Preferably, the secondary box pressure sensing assembly includes a second sensing chamber, a second piston is slidably disposed inside the second sensing chamber, a second slide rod is fixedly disposed on the second piston, a second cross arm is fixedly disposed at the end of the second slide rod away from the second piston, a second drive ring is fixedly disposed at the end of the second cross arm away from the second slide rod, a second drive protrusion is fixedly disposed on the inner wall of the second drive ring, and a second sliding hole is opened on the edge of the second drive ring, and a second top pressure spring is sleeved on the second slide rod; The outer wall of the middle part of the second sensing chamber is fixedly installed on the box body on the other side of the cable branch box. The second piston is located inside the cable branch box, and the second cross arm and the second drive ring are located outside the cable branch box body. The second slide rod slides through one end of the second sensing chamber, and the two ends of the second top pressure spring abut against the inner walls of the second piston and the second sensing chamber, respectively.

[0009] Preferably, the pressure relief chamber assembly includes a pressure relief chamber, and a bottom ring platform and a top ring platform are fixedly provided on the inner wall of one end of the pressure relief chamber. A top groove and a guide rail groove are provided on the top ring platform, and a U-shaped top frame is fixedly provided on the top of the top ring platform. A vertical sliding rod is fixedly provided on the central edge of the U-shaped top frame, and a top platform is fixedly provided on the top of the vertical sliding rod. The middle wall of the pressure relief chamber is fixed to the side box of the cable branch box, and pressure relief chamber assemblies are provided on both sides of the cable branch box.

[0010] Preferably, the pressure relief valve plate assembly includes a pressure relief valve plate, a guide rail slider is fixedly disposed on the top of the pressure relief valve plate, and a slider lever is fixedly disposed on the top of the guide rail slider; The pressure relief valve plate slides on the top ring platform via a guide rail slider and a guide rail groove, and the bottom end of the pressure relief valve plate seals the top end of the bottom ring platform.

[0011] Preferably, the pressure relief drive assembly includes a pressure relief drive shaft, with a pressure relief drive top shaft and a pressure relief drive disc fixedly disposed at both ends of the pressure relief drive shaft, the pressure relief drive top shaft having a spiral groove, and the pressure relief drive disc having a pressure relief drive arc groove; The pressure relief drive shaft is rotatably mounted in the middle of the U-shaped top frame via bearings. The pressure relief drive top shaft is located above the U-shaped top frame, and the pressure relief drive disc is located below the U-shaped top frame. The top of the pressure relief drive top shaft is rotatably mounted on the lower end face of the top platform via bearings.

[0012] Preferably, the pressure relief drive disc is located above the pressure relief valve plate assembly, and the slider lever is inserted into the pressure relief drive arc groove. Through the rotation of the pressure relief drive shaft, the pressure relief drive shaft drives multiple sets of pressure relief valve plate assemblies to synchronously retract or synchronously extend on the bottom ring platform via the pressure relief drive arc groove and the slider lever.

[0013] Preferably, the first drive ring is sleeved on the pressure relief drive top shaft of the pressure relief drive assembly on a set of pressure relief chamber assemblies, the first sliding hole on the first drive ring slides on the vertical sliding rod, and the first drive protrusion is inserted into the spiral sliding groove.

[0014] Preferably, the second drive ring is sleeved on the pressure relief drive top shaft of the pressure relief drive assembly on another set of pressure relief chamber assemblies, the second sliding hole on the second drive ring slides on the vertical sliding rod, and the second drive protrusion is inserted into the spiral sliding groove.

[0015] Preferably, the seat compartment is filled with heat-sensitive paraffin wax, one end of the heat-conducting plate is inserted into the heat-sensitive paraffin wax inside the seat compartment, and the other end of the heat-conducting plate is laid inside the box of the cable branch box.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. By combining temperature and pressure sensing, a graded pressure relief protection system is formed. When the temperature inside the box rises abnormally, temperature-controlled pressure relief is performed first. When the pressure rises suddenly due to situations such as electric arcing or explosion, pressure-triggered pressure relief is further performed, which improves the cable branch box's response capability and safety protection effect to different abnormal conditions.

[0017] 2. The pressure relief is automatically triggered by the expansion of the thermosensitive paraffin due to heat and the pressure inside the chamber pushing the piston. There is no need to install a motor, sensor and electrical control system. It can maintain the pressure relief function in the event of power failure or failure of electrical components. It has the advantages of reliable structure, direct response and convenient maintenance.

[0018] 3. The pressure relief drive disc drives multiple pressure relief valve plates to expand outward synchronously, enabling the pressure relief port to open quickly and evenly. This helps to expand the effective pressure relief area, shorten the pressure release time, avoid local pressure relief obstruction, and reduce the risk of housing deformation, cracking, and internal malfunction expansion. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present invention; Figure 2 This is a cross-sectional view of the primary chamber temperature sensing component and a set of pressure relief chamber components of the present invention; Figure 3 This is a cross-sectional view of the secondary pressure sensing component and another set of pressure relief chamber components of the present invention; Figure 4 This is a perspective view of the primary chamber temperature sensing component of the present invention; Figure 5 This is a cross-sectional view of the primary chamber temperature sensing component of the present invention; Figure 6 This is a perspective view of the two-stage box pressure sensing component of the present invention; Figure 7 This is a cross-sectional view of the secondary box pressure sensing component of the present invention; Figure 8 This is a perspective view of the pressure relief chamber assembly, pressure relief valve plate assembly, and pressure relief drive assembly of the present invention; Figure 9 This is a cross-sectional view of the pressure relief chamber assembly, pressure relief valve plate assembly, and pressure relief drive assembly of the present invention; Figure 10 This is a perspective view of the pressure relief chamber assembly of the present invention; Figure 11 This is a perspective view of the pressure relief valve plate assembly of the present invention; Figure 12 This is a perspective view of the pressure relief drive assembly of the present invention; Figure 13 This is a perspective view of the pressure relief valve plate assembly and the pressure relief drive assembly of the present invention.

[0020] Explanation of reference numerals in the attached drawings: 100, Cable branch box; 200, Primary box temperature sensing assembly; 201, First sensing chamber; 202, First top pressure spring; 203, First piston; 204, First slide rod; 205, First cross arm; 206, First drive ring; 207, First sliding hole; 208, First drive protrusion; 209, Heat-conducting plate; 210, Seat compartment; 300, Secondary box pressure sensing assembly; 301, Second sensing chamber; 302, Second piston; 303, Second top pressure spring; 304, Second slide rod; 305, Second cross arm; 306, Second drive protrusion; 307. Second sliding hole; 308. Second drive ring; 400. Pressure relief chamber assembly; 401. Pressure relief sleeve; 402. U-shaped top frame; 403. Vertical sliding rod; 404. Top platform; 405. Guide rail groove; 406. Top groove; 407. Top ring platform; 408. Bottom ring platform; 500. Pressure relief valve plate assembly; 501. Pressure relief valve plate; 502. Guide rail slider; 503. Slider lever; 600. Pressure relief drive assembly; 601. Pressure relief drive shaft; 602. Pressure relief drive disc; 603. Pressure relief drive arc groove; 604. Spiral groove; 605. Pressure relief drive top shaft. Detailed Implementation

[0021] 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.

[0022] Please see Figures 1-13 As shown, the present invention provides a cable branch box with a graded pressure relief protection structure, including a cable branch box 100, and further comprising: The primary temperature sensing component 200 is installed on one side of the cable branch box 100. The secondary box pressure sensing component 300 is installed on the other side of the cable branch box 100. Two sets of pressure relief chamber assemblies 400 are provided. One set of pressure relief chamber assemblies 400 is installed on the side of the cable branch box 100 near the first-stage box temperature sensing assembly 200, and the other set of pressure relief chamber assemblies 400 is installed on the side of the cable branch box 100 near the second-stage box pressure sensing assembly 300. Multiple pressure relief valve plate assemblies 500 are slidably disposed at the pressure relief port of the pressure relief chamber assembly 400, and are used to synchronously close and seal the pressure relief port of the pressure relief chamber assembly 400. The pressure relief drive assembly 600 is rotatably mounted at the pressure relief port of the pressure relief chamber assembly 400; By physically sensing the high temperature inside the cable branch box 100 through the primary box temperature sensing component 200, the primary box temperature sensing component 200 automatically triggers the pressure relief drive component 600 to drive multiple sets of pressure relief valve plate components 500 to release the blockage of the pressure relief port of the pressure relief chamber component 400, thereby realizing the primary temperature control triggered pressure relief of the pressure relief chamber component 400 on one side of the primary box temperature sensing component 200. The secondary pressure sensing component 300 physically senses the pressure inside the cable branch box 100, causing the secondary pressure sensing component 300 to automatically trigger the pressure relief drive component 600 to drive multiple pressure relief valve plate components 500 to release the blockage of the pressure relief port of the pressure relief chamber component 400, thereby realizing the automatic triggering of pressure relief of the secondary pressure of the pressure relief chamber component 400 on one side of the secondary pressure sensing component 300.

[0023] In a preferred embodiment, please refer to Figure 4 and Figure 5 The primary chamber temperature sensing component 200 includes a first sensing chamber 201, a seat chamber 210 fixedly disposed at one end of the first sensing chamber 201, a heat-conducting plate 209 disposed inside the seat chamber 210, a first piston 203 slidably disposed inside the first sensing chamber 201, a first slide rod 204 fixedly disposed on the first piston 203, a first cross arm 205 fixedly disposed at the end of the first slide rod 204 away from the first piston 203, a first drive ring 206 fixedly disposed at the end of the first cross arm 205 away from the first slide rod 204, a first drive protrusion 208 fixedly disposed on the inner wall of the first drive ring 206, and a first sliding hole 207 opened on the edge of the first drive ring 206; a first top pressure spring 202 is sleeved on the first slide rod 204. The outer wall of the middle part of the first sensing chamber 201 is fixedly installed on the box body on one side of the cable branch box 100. The seat chamber 210 and the heat conduction plate 209 are located inside the cable branch box 100, and the first cross arm 205 and the first drive ring 206 are located outside the box body of the cable branch box 100. The first slide rod 204 slides through one end of the first sensing chamber 201, and the two ends of the first top pressure spring 202 respectively abut against the first piston 203 and the inner wall of the first sensing chamber 201. The first drive ring 206 is sleeved on the pressure relief drive top shaft 605 of the pressure relief drive assembly 600 on a set of pressure relief chamber assemblies 400. The first sliding hole 207 on the first drive ring 206 slides on the vertical sliding rod 403. The first drive protrusion 208 is inserted into the spiral groove 604. The seat compartment 210 is filled with heat-sensitive paraffin wax. One end of the heat-conducting plate 209 is inserted into the heat-sensitive paraffin wax inside the seat compartment 210, and the other end of the heat-conducting plate 209 is laid inside the box of the cable branch box 100.

[0024] In a preferred embodiment, please refer to Figure 6 and Figure 7 The secondary pressure sensing assembly 300 includes a second sensing chamber 301, a second piston 302 slidably disposed inside the second sensing chamber 301, a second slide rod 304 fixedly disposed on the second piston 302, a second cross arm 305 fixedly disposed at the end of the second slide rod 304 away from the second piston 302, a second drive ring 308 fixedly disposed at the end of the second cross arm 305 away from the second slide rod 304, a second drive protrusion 306 fixedly disposed on the inner wall of the second drive ring 308, and a second sliding hole 307 opened on the edge of the second drive ring 308; a second top pressure spring 303 is sleeved on the second slide rod 304. The outer wall of the middle part of the second sensing chamber 301 is fixedly installed on the box body on the other side of the cable branch box 100. The second piston 302 is located inside the cable branch box 100, and the second cross arm 305 and the second drive ring 308 are located outside the box body of the cable branch box 100. The second slide rod 304 slides through one end of the second sensing chamber 301, and the two ends of the second top pressure spring 303 respectively abut against the inner wall of the second piston 302 and the second sensing chamber 301. The second drive ring 308 is sleeved on the pressure relief drive top shaft 605 of the pressure relief drive assembly 600 on another set of pressure relief chamber assembly 400. The second sliding hole 307 on the second drive ring 308 slides on the vertical sliding rod 403, and the second drive protrusion 306 is inserted into the spiral sliding groove 604.

[0025] In a preferred embodiment, please refer to Figure 10 The pressure relief chamber assembly 400 includes a pressure relief chamber 401. A bottom ring platform 408 and a top ring platform 407 are fixedly provided on the inner wall of one end of the pressure relief chamber 401. A top groove 406 and a guide rail groove 405 are provided on the top ring platform 407. A U-shaped top frame 402 is fixedly provided on the top of the top ring platform 407. A vertical sliding rod 403 is fixedly provided on the central edge of the U-shaped top frame 402. A top platform 404 is fixedly provided on the top of the vertical sliding rod 403. The middle wall of the pressure relief chamber 401 is fixed to the side box of the cable branch box 100, and pressure relief chamber assemblies 400 are provided on both sides of the cable branch box 100.

[0026] In a preferred embodiment, please refer to Figure 11 The pressure relief valve plate assembly 500 includes a pressure relief valve plate 501, a guide rail slider 502 is fixedly mounted on the top of the pressure relief valve plate 501, and a slider lever 503 is fixedly mounted on the top of the guide rail slider 502. The pressure relief valve plate 501 slides on the top ring platform 407 via the guide rail slider 502 and the guide rail groove 405, and the bottom end of the pressure relief valve plate 501 seals the top end of the bottom ring platform 408.

[0027] In a preferred embodiment, please refer to Figure 12 The pressure relief drive assembly 600 includes a pressure relief drive shaft 601. A pressure relief drive top shaft 605 and a pressure relief drive disc 602 are fixedly installed at both ends of the pressure relief drive shaft 601. A spiral groove 604 is provided on the pressure relief drive top shaft 605, and a pressure relief drive arc groove 603 is provided on the pressure relief drive disc 602. The pressure relief drive shaft 601 is rotatably mounted in the middle of the U-shaped top frame 402 via a bearing, the pressure relief drive top shaft 605 is located above the U-shaped top frame 402, the pressure relief drive disc 602 is located below the U-shaped top frame 402, and the top of the pressure relief drive top shaft 605 is rotatably mounted on the lower end face of the top platform 404 via a bearing. The pressure relief drive disc 602 is located above the pressure relief valve plate assembly 500. The slider lever 503 is inserted into the pressure relief drive arc groove 603. Through the rotation of the pressure relief drive shaft 601, the pressure relief drive shaft 601 drives multiple sets of pressure relief valve plate assemblies 500 to slide synchronously inward or outward on the bottom ring platform 408 via the pressure relief drive arc groove 603 and the slider lever 503.

[0028] The working principle of this invention is as follows: A primary temperature sensing component 200 is provided on one side of the cable branch box 100, along with a pressure relief chamber assembly 400 that cooperates with the primary temperature sensing component 200. On the other side of the cable branch box 100, a secondary pressure sensing component 300 is provided, along with another pressure relief chamber assembly 400 that cooperates with the secondary pressure sensing component 300. The pressure relief chamber assembly 400 serves as a two-stage pressure relief port for the cable branch box 100. To achieve rapid opening or closing of the pressure relief chamber assembly 400, this invention provides multiple sets of pressure relief valve plate assemblies 500 at the pressure relief port of the pressure relief chamber assembly 400. In specific use, the pressure relief valve plate 501 slides on the top ring platform 407 via the guide rail slider 502 and the guide rail groove 405. The bottom end of the pressure relief valve plate 501 seals the top end of the bottom ring platform 408. When pressure relief is required, the multiple sets of pressure relief valves... The synchronous outward expansion of the plate assembly 500 at the top surface of the bottom ring platform 408 can seal the top surface of the bottom ring platform 408, enabling the rapid opening of the pressure relief port of the pressure relief chamber assembly 400. This allows the cable branch box 100 to be pressure-relieved and protected by the pressure relief chamber assembly 400. In order to enable multiple pressure relief valve plate assemblies 500 to synchronously and rapidly expand and open at the pressure relief port of the pressure relief chamber assembly 400, the invention is equipped with a pressure relief drive assembly 600 at the top. In actual use, the pressure relief drive disc 602 is rotatably positioned above the pressure relief valve plate 501. Through the rotation of the pressure relief drive disc 602, the pressure relief drive disc 602 drives multiple pressure relief valve plate assemblies 500 to rapidly and synchronously expand outward at the bottom ring platform 408 via the pressure relief drive arc groove 603 and the slider lever 503. In this way, the pressure relief port of the pressure relief chamber assembly 400 can be rapidly opened. Through the above structural configuration, the present invention achieves the ability to centrally close and quickly and synchronously open the pressure relief port of the pressure relief chamber assembly 400. Specifically, multiple sets of pressure relief valve plate assemblies 500 are arranged circumferentially along the pressure relief chamber assembly 400. The pressure relief valve plate 501 slides radially on the top ring platform 407 via the guide rail slider 502 and the guide rail groove 405, and the bottom end of the pressure relief valve plate 501 blocks the top end of the bottom ring platform 408, so that the pressure relief port remains closed under normal conditions. When the pressure relief drive disc 602 rotates, the pressure relief drive arc groove 6... 03 The slider lever 503 synchronously drives multiple pressure relief valve plates 501 to unfold outward, thereby quickly releasing the blockage of the pressure relief port. This process transforms the rotation of a single pressure relief drive disc 602 into the synchronous radial displacement of multiple pressure relief valve plates 501, overcoming the defects of traditional single pressure relief cover having large opening resistance, slow opening speed, and insufficient effective pressure relief area. This allows the pressure relief port to open quickly and evenly, improving the discharge efficiency of high-temperature and high-pressure gases in the chamber and reducing the risk of deformation, cracking, and door breaking of the chamber.

[0029] When the temperature inside the cable branch box 100 rises, the pressure or temperature inside the cable branch box 100 urgently needs to be released. In actual use, a primary box temperature sensing component 200 is installed on one side of the cable branch box 100, and a pressure relief chamber component 400 that cooperates with the primary box temperature sensing component 200 is also installed. In actual use, the chamber 210 on the primary box temperature sensing component 200 is filled with thermosensitive paraffin wax. One end of the heat-conducting plate 209 is inserted into the thermosensitive paraffin wax in the chamber 210, and the other end of the heat-conducting plate 209 is laid inside the box of the cable branch box 100. When the temperature inside the cable branch box 100 rises, the high temperature inside the cable branch box 100 is transferred to the thermosensitive paraffin wax in the chamber 210 through the heat-conducting plate 209. At this time, the thermosensitive paraffin wax expands due to heat. The expanding thermosensitive paraffin wax overcomes the top pressure of the first top pressure spring 202 and pushes the first piston 203 outward. 03 The first drive ring 206 is pushed outward on the pressure relief drive top shaft 605 by the first slide rod 204 and the first cross arm 205. At this time, since the first drive ring 206 is sleeved on the pressure relief drive top shaft 605 of the pressure relief drive assembly 600 on a set of pressure relief chamber assemblies 400, and the first drive protrusion 208 is inserted in the spiral groove 604, the pressure relief drive top shaft 605 is rotated by the cooperation of the first drive protrusion 208 and the spiral groove 604. The pressure relief drive top shaft 605 drives the pressure relief drive disc 602 to rotate through the pressure relief drive shaft 601. The pressure relief drive disc 602 drives multiple sets of pressure relief valve plate assemblies 500 to extend outward synchronously at the bottom ring platform 408 through the pressure relief drive arc groove 603 and the slider lever 503. In this way, the pressure relief port at the bottom ring platform 408 is opened quickly and synchronously, thereby realizing the first-level temperature control triggered pressure relief in the cable branch box 100. Through the above structural configuration, the present invention achieves physical sensing of abnormal temperature rise inside the cable branch box 100 and first-level automatic pressure relief capability. Specifically, the heat-conducting plate 209 transfers the heat inside the cable branch box 100 to the thermosensitive paraffin in the housing 210. After the thermosensitive paraffin expands due to heat, it pushes the first piston 203 to move outward against the force of the first top pressure spring 202. The first piston 203 drives the first drive ring 206 to generate axial displacement through the first slide rod 204 and the first cross arm 205. The first drive protrusion 208 cooperates with the spiral groove 604 to move the first drive ring 206. The axial displacement is converted into the rotation of the pressure relief drive top shaft 605 and the pressure relief drive disc 602, which in turn drives multiple sets of pressure relief valve plate assemblies 500 to expand outward synchronously and open the pressure relief port. This process can actively relieve pressure and dissipate heat during the abnormal temperature rise in the box, overcoming the defect of the traditional pressure relief structure that only opens passively after the pressure in the box reaches a high level. It can complete temperature sensing and pressure relief triggering without relying on temperature sensors, motors or controllers, which is conducive to releasing heat in advance and suppressing the pressure in the box from continuing to rise, thus improving the early protection capability of the cable branch box 100 against abnormal heat generation faults.

[0030] When the pressure inside the cable branch box 100 increases due to arcing or other reasons, a secondary pressure sensing component 300 is installed on one side of the cable branch box 100, and a pressure relief chamber component 400 is also installed to cooperate with the secondary pressure sensing component 300. In actual use, when the pressure inside the cable branch box 100 increases, the high pressure inside the cable branch box 100 overcomes the top pressure of the second top pressure spring 303 and pushes the second piston 302 outward. At this time, the second piston 302 drives the second drive ring 308 to push outward on the pressure relief drive top shaft 605 through the second slide rod 304 and the second cross arm 305. At this time, since the second drive ring 308 is sleeved on another set of pressure relief chamber components... On the pressure relief drive top shaft 605 of the pressure relief drive assembly 600, the second drive protrusion 306 is inserted into the spiral groove 604. Through the cooperation of the second drive protrusion 306 and the spiral groove 604, the pressure relief drive top shaft 605 is rotated. The pressure relief drive top shaft 605 drives the pressure relief drive disc 602 to rotate through the pressure relief drive shaft 601. The pressure relief drive disc 602 drives multiple sets of pressure relief valve plate assemblies 500 to extend synchronously at the bottom ring platform 408 through the pressure relief drive arc groove 603 and the slider lever 503. In this way, the pressure relief port at the bottom ring platform 408 is opened quickly and synchronously, thereby realizing the automatic triggering of pressure relief of the secondary pressure in the cable branch box 100. Through the above structural configuration, the present invention achieves mechanical sensing and two-stage automatic pressure relief capability for sudden pressure rise inside the cable branch box 100. Specifically, when an arc flash or other fault causes the internal pressure of the box to rise, the internal pressure directly acts on the second piston 302 and overcomes the force of the second top pressure spring 303, causing the second piston 302 to drive the second drive ring 308 outward through the second slide rod 304 and the second cross arm 305. The second drive protrusion 306 cooperates with the spiral slide groove 604 to convert the axial displacement of the second drive ring 308 into pressure relief drive top shaft 605, pressure relief drive shaft 601, and pressure relief drive disc 60. The rotation of the pressure relief drive disc 602, through the pressure relief drive arc groove 603 and the slider lever 503, drives multiple pressure relief valve plate assemblies 500 to expand outward synchronously, thereby quickly opening the pressure relief port. This process enables the pressure relief action to directly respond to changes in the pressure inside the box, overcoming the defect that traditional electrically controlled pressure relief devices may not be able to trigger normally in the event of power failure, damage to electrical components, or arc interference. It also forms a graded protection relationship with the first-level temperature-controlled pressure relief, rapidly expanding the pressure relief channel when the pressure inside the box suddenly rises, shortening the release time of high-pressure gas, and improving the safety and reliability of the cable branch box 100 under sudden faults such as arc flash explosion.

[0031] 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, the scope of which is defined by the appended technical solutions and their equivalents.

Claims

1. A cable branch box with a graded pressure relief protection structure, comprising a cable branch box (100), characterized in that, Also includes: A primary box temperature sensing component (200) is installed on one side of the cable branch box (100); A secondary box pressure sensing component (300) is installed on the other side of the cable branch box (100); Two sets of pressure relief chamber assemblies (400), one set of pressure relief chamber assemblies (400) is installed on the side of the cable branch box (100) near the first-stage box temperature sensing assembly (200), and the other set of pressure relief chamber assemblies (400) is installed on the side of the cable branch box (100) near the second-stage box pressure sensing assembly (300); Multiple sets of pressure relief valve plate assemblies (500) are slidably disposed at the pressure relief port of the pressure relief chamber assembly (400) for synchronously closing and sealing the pressure relief port of the pressure relief chamber assembly (400); A pressure relief drive assembly (600) is rotatably disposed at the pressure relief port of the pressure relief chamber assembly (400); By physically sensing the high temperature inside the cable branch box (100) through the primary box temperature sensing component (200), the primary box temperature sensing component (200) automatically triggers the pressure relief drive component (600) to drive multiple sets of pressure relief valve plate components (500) to release the blockage of the pressure relief port of the pressure relief chamber component (400), thereby realizing the primary temperature control triggered pressure relief of the pressure relief chamber component (400) on one side of the primary box temperature sensing component (200); By physically sensing the pressure inside the cable branch box (100) through the secondary box pressure sensing component (300), the secondary box pressure sensing component (300) automatically triggers the pressure relief drive component (600) to drive multiple sets of pressure relief valve plate components (500) to release the blockage of the pressure relief port of the pressure relief chamber component (400), thereby realizing the automatic triggering of pressure relief of the secondary pressure of the pressure relief chamber component (400) on one side of the secondary box pressure sensing component (300).

2. A cable branch box with a graded pressure relief protection structure according to claim 1, characterized in that: The first-stage chamber temperature sensing component (200) includes a first sensing chamber (201), a seat chamber (210) is fixedly provided at one end of the first sensing chamber (201), a heat-conducting plate (209) is provided inside the seat chamber (210), a first piston (203) is slidably provided inside the first sensing chamber (201), a first slide rod (204) is fixedly provided on the first piston (203), a first cross arm (205) is fixedly provided at the end of the first slide rod (204) away from the first piston (203), a first drive ring (206) is fixedly provided at the end of the first cross arm (205) away from the first slide rod (204), a first drive protrusion (208) is fixedly provided on the inner wall of the first drive ring (206), and a first sliding hole (207) is opened on the edge of the first drive ring (206). A first top pressure spring (202) is sleeved on the first slide rod (204). The outer wall of the middle part of the first sensing chamber (201) is fixedly installed on the box body on one side of the cable branch box (100). The seat chamber (210) and the heat conduction plate (209) are located inside the cable branch box (100). The first cross arm (205) and the first drive ring (206) are located outside the box body of the cable branch box (100). The first slide bar (204) slides through one end of the first sensing chamber (201), and the two ends of the first top pressure spring (202) abut against the inner wall of the first piston (203) and the first sensing chamber (201), respectively.

3. A cable branch box with a graded pressure relief protection structure according to claim 2, characterized in that: The secondary box pressure sensing assembly (300) includes a second sensing chamber (301), a second piston (302) is slidably disposed inside the second sensing chamber (301), a second slide rod (304) is fixedly disposed on the second piston (302), a second cross arm (305) is fixedly disposed at one end of the second slide rod (304) away from the second piston (302), a second drive ring (308) is fixedly disposed at one end of the second cross arm (305) away from the second slide rod (304), a second drive protrusion (306) is fixedly disposed on the inner wall of the second drive ring (308), and a second sliding hole (307) is opened on the edge of the second drive ring (308). A second top pressure spring (303) is sleeved on the second slide rod (304). The outer wall of the middle part of the second sensing chamber (301) is fixedly installed on the box body on the other side of the cable branch box (100), the second piston (302) is located inside the cable branch box (100), and the second cross arm (305) and the second drive ring (308) are located outside the box body of the cable branch box (100). The second slide bar (304) slides through one end of the second sensing chamber (301), and the two ends of the second top pressure spring (303) abut against the inner walls of the second piston (302) and the second sensing chamber (301), respectively.

4. A cable branch box with a graded pressure relief protection structure according to claim 3, characterized in that: The pressure relief chamber assembly (400) includes a pressure relief chamber (401). A bottom ring platform (408) and a top ring platform (407) are fixedly provided on the inner wall of one end of the pressure relief chamber (401). A top groove (406) and a guide rail groove (405) are provided on the top ring platform (407). A U-shaped top frame (402) is fixedly provided on the top of the top ring platform (407). A vertical slide rod (403) is fixedly provided on the central edge of the U-shaped top frame (402). A top platform (404) is fixedly provided on the top of the vertical slide rod (403). The middle wall of the pressure relief chamber (401) is fixed to the side box of the cable branch box (100), and pressure relief chamber assemblies (400) are provided on both sides of the cable branch box (100).

5. A cable branch box with a graded pressure relief protection structure according to claim 4, characterized in that: The pressure relief valve plate assembly (500) includes a pressure relief valve plate (501), a guide rail slider (502) is fixedly provided on the top of the pressure relief valve plate (501), and a slider lever (503) is fixedly provided on the top of the guide rail slider (502). The pressure relief valve plate (501) slides on the top ring platform (407) via the guide rail slider (502) and the guide rail groove (405), and the bottom end of the pressure relief valve plate (501) seals the top end of the bottom ring platform (408).

6. A cable branch box with a graded pressure relief protection structure according to claim 5, characterized in that: The pressure relief drive assembly (600) includes a pressure relief drive shaft (601), with a pressure relief drive top shaft (605) and a pressure relief drive disc (602) fixedly installed at both ends of the pressure relief drive shaft (601). A spiral groove (604) is provided on the pressure relief drive top shaft (605), and a pressure relief drive arc groove (603) is provided on the pressure relief drive disc (602). The pressure relief drive shaft (601) is rotatably mounted in the middle of the U-shaped top frame (402) via a bearing. The pressure relief drive top shaft (605) is located above the U-shaped top frame (402), and the pressure relief drive disc (602) is located below the U-shaped top frame (402). The top of the pressure relief drive top shaft (605) is rotatably mounted on the lower end face of the top platform (404) via a bearing.

7. A cable branch box with a graded pressure relief protection structure according to claim 6, characterized in that: The pressure relief drive disc (602) is located above the pressure relief valve plate assembly (500). The slider lever (503) is inserted in the pressure relief drive arc groove (603). Through the rotation of the pressure relief drive shaft (601), the pressure relief drive shaft (601) drives multiple sets of pressure relief valve plate assemblies (500) to synchronously retract or synchronously extend on the bottom ring platform (408) through the pressure relief drive arc groove (603) and the slider lever (503).

8. A cable branch box with a graded pressure relief protection structure according to claim 6, characterized in that: The first drive ring (206) is sleeved on the pressure relief drive top shaft (605) of the pressure relief drive assembly (600) on a set of pressure relief chamber assemblies (400). The first sliding hole (207) on the first drive ring (206) slides on the vertical slide rod (403). The first drive protrusion (208) is inserted into the spiral groove (604).

9. A cable branch box with a graded pressure relief protection structure according to claim 6, characterized in that: The second drive ring (308) is sleeved on the pressure relief drive top shaft (605) of the pressure relief drive assembly (600) on another set of pressure relief chamber assemblies (400). The second sliding hole (307) on the second drive ring (308) slides on the vertical slide rod (403). The second drive protrusion (306) is inserted into the spiral groove (604).

10. A cable branch box with a graded pressure relief protection structure according to claim 6, characterized in that: The seat compartment (210) is filled with heat-sensitive paraffin wax. One end of the heat-conducting plate (209) is inserted into the heat-sensitive paraffin wax in the seat compartment (210), and the other end of the heat-conducting plate (209) is laid in the box inside the cable branch box (100).

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