Generator enclosed bus ct terminal box
By designing a side-entry structure and multiple clamping mechanisms, the problem of cable stress damage in the CT output box of the generator enclosed busbar was solved, achieving stable operation and improved safety of the CT.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUANENG LUOYUAN POWER GENERATION CO LTD
- Filing Date
- 2026-02-27
- Publication Date
- 2026-06-09
AI Technical Summary
The existing generator enclosed bus CT outgoing box adopts the top-entry method, which leads to a high risk of stress damage at the cable root, which can easily cause CT open circuit faults, posing safety hazards and equipment damage risks.
It adopts a side-entry cable structure and is equipped with multiple clamping mechanisms at the cable inlet, including external clamping mechanisms and internal clamping mechanisms. The cable is double-fixed through components such as a fixed ring, a rotating ring, a linkage ring and a clamping plate, eliminating stress at the cable root.
It effectively prevents open circuit faults in CTs, avoids high-voltage breakdown and electric shock threats, ensures stable transmission of current signals, prevents relay protection malfunctions, reduces the risk of equipment damage, and improves operational reliability and safety.
Smart Images
Figure CN122178223A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a generator enclosed bus CT junction box, belonging to the field of junction box technology. Background Technology
[0002] In the field of power production, the generator enclosed bus CT (current transformer) outlet box is a key device to ensure the transmission of current signals in the power system and the normal operation of relay protection. Its operational stability is directly related to the safe and reliable operation of generator sets and power grids.
[0003] Currently, the widely used generator enclosed busbar CT outlet boxes in the industry generally adopt a top-entry wiring method, that is, the cable is connected from the top of the outlet box to achieve the circuit connection. As the operating cycle of the generator set extends, its inherent structural defects gradually become apparent, specifically manifested as follows: 1. High risk of cable stress damage: The top-entry method causes continuous tensile stress at the root and terminal of the cable under the action of gravity and installation tension. Long-term operation can easily cause wear of the cable insulation layer and conductor fatigue. In severe cases, it can directly lead to cable breakage, triggering CT open circuit fault, and then inducing major safety accidents such as equipment damage and unit shutdown. 2. Significant safety hazards: After the CT is opened, thousands or even tens of thousands of volts of high voltage will be induced on the secondary side, which may not only break down the equipment insulation and burn out related components of the unit, but also pose a serious electric shock threat to on-site maintenance personnel; at the same time, the interruption of the current signal will cause the relay protection to malfunction or fail to operate, and will not be able to respond to the power grid fault in time, which may easily cause the accident to escalate; in addition, the temperature of the CT core will rise sharply due to magnetic saturation, which may melt the insulation of the core winding, cause a fire and permanently damage the CT equipment.
[0004] Therefore, improvements are urgently needed. Summary of the Invention
[0005] To overcome the shortcomings of the prior art, this invention designs a generator enclosed bus CT junction box, which adopts a side-entry structure and is equipped with multiple clamping mechanisms at the inlet, effectively eliminating the stress at the cable root, thereby preventing CT open circuit faults, and improving maintenance convenience and operational reliability.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: A generator enclosed bus CT junction box includes a main junction box, a terminal block connected to the top of the main junction box, a secondary junction box connected to the top of the terminal block, and an inlet hole on the side of the secondary junction box. One end of the cable enters the interior of the secondary junction box through the inlet hole, bends downward, passes through the terminal block, and enters the interior of the main junction box. An external clamping mechanism for clamping cables is installed on the outer wall of the secondary junction box at the cable inlet, and an internal clamping mechanism for clamping cables is installed inside the secondary junction box.
[0007] Furthermore, the external clamping mechanism includes a fixed ring, a rotating ring concentrically mounted on the outside of the fixed ring, and a linkage ring concentrically spaced on the outside of the rotating ring. Multiple hinged posts evenly arranged circumferentially are also fixed on the outside of the fixed ring. A hinged rod is hinged to the free end of each hinged post. The free end of the hinged rod passes through the gap between the rotating ring and the linkage ring and is rotatably connected to a clamping disc. A sliding sleeve is slidably fitted onto the hinged rod, and the sliding sleeve is hinged to the linkage ring. A drive assembly for driving the rotating ring to rotate is also provided on the outside of the fixed ring.
[0008] Furthermore, the drive assembly includes a drive motor and a lead screw. A hinge protrusion is provided on the outer side of the rotating ring. A hinge block one is hingedly mounted on the hinge protrusion. A hinge block two is hingedly mounted on the fixed ring. One end of the lead screw is threaded through the hinge block one. The other end of the lead screw rotates through the hinge block two and is then connected to the drive motor for transmission.
[0009] Furthermore, the fixing ring is connected to the secondary junction box through several connecting posts evenly arranged circumferentially, and an inlet cylinder sleeved over the cable is provided between the fixing ring and the inlet hole.
[0010] Furthermore, the top of the secondary junction box is detachably provided with a cover, and each of the four corners of the cover is connected to a plug post. The bottom end of the plug post passes through the cover and the secondary junction box in sequence and is detachably connected to the main junction box. The top end of the plug post is locked by a lock nut.
[0011] Furthermore, the internal clamping mechanism includes a sliding box installed inside the secondary junction box. A connecting block is integrally connected to the top of the sliding box, and a semi-circular upper collar is integrally connected to the free end of the connecting block. A lower collar that cooperates with the upper collar and is used to clamp the cable is provided at the bottom end of the upper collar. An ejector slide rod is fixedly connected to the bottom end of the lower collar. A reset ejector mechanism is installed inside the sliding box to push the ejector slide rod upward after the box cover is locked.
[0012] Furthermore, the reset ejection mechanism includes a sliding rod one, a top-connecting rod, and a sliding rod two. The sliding box is provided with a horizontal slot and vertical slot one and vertical slot two, which are vertically intersecting at both ends of the horizontal slot. The sliding rod one is slidably installed in the vertical slot one, the sliding rod two is slidably installed in the vertical slot two, and the top-connecting rod is slidably installed in the horizontal slot. The top of the sliding rod one extends out of the vertical slot one and fits the bottom of the box cover. The bottom of the sliding rod one is provided with a first mating slope. The bottom of the sliding rod two is provided with a second mating slope. One end of the top connecting rod is provided with a first lifting slope that abuts against the first mating slope. The other end of the top connecting rod is provided with a second lifting slope that abuts against the second mating slope. The top end of the sliding rod 2 is fixedly connected to the bottom end of the ejector slide rod, and a spring sleeved on the outside of the ejector slide rod is connected between the top end of the sliding rod 2 and the top end of the vertical slot 2.
[0013] Furthermore, a pressure block is fixedly connected to one end of the sliding rod.
[0014] Furthermore, sealing rings are provided at the connection points between the junction box and the main junction box and the auxiliary junction box.
[0015] Furthermore, the cable inlet hole is located in the middle of the side of the secondary junction box.
[0016] Compared with the prior art, the present invention has the following features and beneficial effects: 1. In this invention, since the cable adopts a side entry method and is fixed by both external and internal clamping mechanisms, the situation of the cable root bearing continuous tensile stress for a long time in the traditional top entry structure is completely changed. This significantly reduces the risk of cable insulation wear, conductor fatigue, and even breakage caused by stress damage, and eliminates the hidden danger of CT open circuit fault caused by cable breakage from the root.
[0017] 2. In this invention, since the open circuit fault of the CT is effectively prevented, the risk of the thousands of volts of high voltage generated by the open circuit of the CT to break down the insulation of the equipment and the threat of electric shock to the on-site operation and maintenance personnel are avoided. At the same time, the stable transmission of current signals is guaranteed, ensuring that the relay protection device can operate correctly, preventing the expansion of power grid accidents caused by the CT open circuit causing the protection to malfunction or fail to operate, and eliminating the serious consequences of the CT core rapidly heating up and melting the winding insulation due to over-excitation magnetic saturation, causing fire and permanent damage to the equipment. Attached Figure Description
[0018] Figure 1 This is a three-dimensional structural schematic diagram of the present invention; Figure 2 This is a side view of the structure of the present invention; Figure 3 This is a schematic diagram of the installation structure of the external clamping mechanism of the present invention from a first-view perspective; Figure 4 This is a schematic diagram of the installation structure of the external clamping mechanism of the present invention from a second perspective; Figure 5 This is a schematic diagram of another installation structure of the external clamping mechanism of the present invention; Figure 6This is a schematic diagram of the internal structure of the internal clamping mechanism of the present invention from a first-view perspective; Figure 7 This is a schematic diagram of the internal structure of the internal clamping mechanism of the present invention from a second perspective.
[0019] The attached diagrams are labeled as follows: 1. Main junction box; 11. Junction tube; 2. Secondary junction box; 21. Box cover; 22. Locking nut; 23. Plug-in post; 24. Cable inlet hole; 3. External clamping mechanism; 31. Fixing ring; 311. Connecting post; 312. Cable inlet tube; 32. Rotating ring; 33. Linkage ring; 34. Drive assembly; 341. Hinge block one; 342. Drive motor; 343. Hinge block two; 344. Lead screw; 345. Hinge protrusion; 35. Hinge post; 36. Hinge rod; 37. 38. Sliding sleeve; 4. Clamping disc; 5. Cable; 6. Internal clamping mechanism; 7. Sliding box; 8. Vertical slot one; 9. Horizontal slot; 10. Vertical slot two; 11. Sliding rod one; 12. Pressure block; 13. Connecting inclined surface one; 14. Top connecting rod; 15. Lifting inclined surface one; 16. Lifting inclined surface two; 17. Sliding rod two; 18. Connecting inclined surface two; 19. Ejecting slide rod; 20. Lower collar; 20. Upper collar; 21. Connecting block; 22. Spring. Detailed Implementation
[0020] The present invention will now be described in more detail with reference to the embodiments.
[0021] Example 1 Please see Figure 1 and Figure 2 The generator enclosed bus CT junction box of this embodiment includes a main junction box 1, a terminal block 11 connected to the top of the main junction box 1, a secondary junction box 2 connected to the top of the terminal block 11, and an inlet hole 24 opened on the side of the secondary junction box 2.
[0022] The length and width of the secondary junction box 2 are the same as those of the main junction box 1, and the height of the secondary junction box 2 is 8cm to 12cm. In this embodiment, the height of the secondary junction box 2 is 12cm.
[0023] Both the auxiliary junction box 2 and the main junction box 1 are made of high-strength flame-retardant insulating materials to ensure structural strength and electrical safety performance, and to avoid compatibility issues caused by material differences.
[0024] Specifically, one of the terminals of cable 4 enters the secondary junction box 2 through the inlet hole 24, bends downward, passes through the junction tube 11, and enters the main junction box 1 for electrical connection.
[0025] The cable inlet 24 is provided with an external clamping mechanism 3 installed on the outer wall of the secondary junction box 2 for clamping the cable 4, and the secondary junction box 2 is provided with an internal clamping mechanism 5 for clamping the cable 4.
[0026] The main junction box 1 has an openable cover at the top. When the cover is removed, the junction box 11 and the auxiliary junction box 2 can be disassembled at the same time, which makes it easy to observe and inspect the cable 4 connection inside the main junction box 1.
[0027] As can be seen from the above description, during operation, cable 4 is first introduced through the inlet hole 24 on the side of the auxiliary junction box 2. After entering the auxiliary junction box 2, cable 4 is bent downwards, then passes through the junction tube 11 which is connected to the top of the main junction box 1, and finally enters the main junction box 1 to complete the electrical connection with the CT.
[0028] During this process, cable 4 needs to pass through two key locations in sequence: At the position where the cable enters the inlet hole 24, the external clamping mechanism 3 installed on the outer wall of the secondary junction box 2 initially clamps and fixes the cable 4 to eliminate the pulling force from the outside.
[0029] Subsequently, inside the secondary junction box 2, the internal clamping mechanism 5 clamps the cable 4 again.
[0030] Through the coordinated action of the external clamping mechanism 3 and the internal clamping mechanism 5, the cable 4 is reliably positioned at the inlet hole 24 and inside the secondary junction box 2. This effectively distributes and bears the gravity and external tension that might have directly acted on the terminals inside the main junction box 1 onto the secondary junction box 2, the external clamping mechanism 3, and the internal clamping mechanism 5, ensuring that the cable segment entering the main junction box 1 is in a stress-free or low-stress state.
[0031] Furthermore, the top of the secondary junction box 2 is detachably provided with a cover 21, and each of the four corners of the cover 21 is connected to a plug post 23. The bottom end of the plug post 23 passes through the cover 21 and the secondary junction box 2 in sequence and is threadedly connected to the cover body at the top of the main junction box 1. The top end of the plug post 23 is locked by a lock nut 22.
[0032] Operators only need to loosen the locking nut 22 to remove the cover 21, which is simple and quick to operate. At the same time, the positioning function of the plug post 23 ensures the accurate alignment of the cover 21 during reinstallation, further improving the efficiency of daily maintenance work.
[0033] The beneficial effects of the present invention are as follows: First, since the cable 4 adopts a side entry method and is double-fixed by the external clamping mechanism 3 and the internal clamping mechanism 5, the situation of the cable root bearing continuous tensile stress for a long time in the traditional top entry structure is completely changed, which significantly reduces the risk of cable insulation wear, conductor fatigue and even breakage caused by stress damage, and eliminates the hidden danger of CT open circuit fault caused by cable breakage from the root.
[0034] Secondly, by effectively preventing CT open-circuit faults, the risk of equipment insulation breakdown caused by the thousands of volts of high voltage generated by CT open-circuit is avoided, as well as the threat of electric shock to on-site maintenance personnel. At the same time, the stable transmission of current signals is ensured, ensuring that the relay protection device can operate correctly. This prevents the expansion of power grid accidents caused by CT open-circuit maloperation or failure to operate, and eliminates the serious consequences of CT core overheating and melting of winding insulation due to overexcitation magnetic saturation, leading to fire and permanent damage to equipment.
[0035] Furthermore, sealing rings are provided at the connection points between the junction box 11 and the main junction box 1 and the auxiliary junction box 2, thereby improving the sealing performance of the entire junction box. This can reliably prevent external moisture, dust and small particles from entering the box from the connection gaps, avoiding the creepage fault caused by the decrease in insulation performance due to moisture or the accumulation of dust, and significantly improving the operational reliability of the equipment in harsh environments.
[0036] Furthermore, the inlet hole 24 is located in the middle of the side of the auxiliary junction box 2, and the inlet position of the cable 4 is in the center height area of the auxiliary junction box 2. After the cable 4 enters, it bends downward and passes through the junction box 11 more smoothly and naturally, which effectively avoids excessive bending or twisting of the cable due to the inlet position being too high or too low. This further optimizes the stress state of the cable 4, reduces stress concentration at the bend, and thus extends the service life of the cable.
[0037] Example 2 Please see Figure 3 and Figure 4 In this embodiment, the generator enclosed bus CT junction box, based on the above embodiment one, includes an external clamping mechanism 3 comprising a fixed ring 31, a rotating ring 32 concentrically mounted on the outside of the fixed ring 31, and a linkage ring 33 concentrically spaced on the outside of the rotating ring 32.
[0038] Specifically, the rotating ring 32 and the linkage ring 33 are connected by connecting blocks, and three connecting blocks are provided and evenly arranged along the circumference.
[0039] Three hinged posts 35 are vertically fixed on the outside of the fixed ring 31 and are evenly arranged in the circumferential direction. The free end of the hinged post 35 is hinged to a hinged rod 36. The free end of the hinged rod 36 passes through the gap between the rotating ring 32 and the linkage ring 33 and is rotatably connected to a clamping plate 38. A sliding sleeve 37 is also slidably sleeved on the hinged rod 36 and is hingedly installed on the linkage ring 33.
[0040] In this embodiment, the clamping disc 38 is made of an elastic insulating material.
[0041] Meanwhile, a drive assembly 34 for driving the rotating ring 32 to rotate is also provided on the outside of the fixed ring 31.
[0042] The three connecting blocks and three hinge posts 35 are staggered to avoid interference between the connecting blocks and the swing of the hinge rod 36.
[0043] As can be seen from the above description, when the cable 4 passes through the fixed ring 31 and needs to be clamped, the rotating ring 32 is driven to rotate relative to the fixed ring 31 by the driving component 34. Since the rotating ring 32 and the linkage ring 33 are fixedly connected by three connecting blocks evenly arranged in the circumferential direction, the rotation of the rotating ring 32 will drive the linkage ring 33 to rotate synchronously.
[0044] At this time, since the sliding sleeve 37 is hinged to the linkage ring 33 and the hinge rod 36 is slidably sleeved in the sliding sleeve 37, and one end of the hinge rod 36 is hinged to the hinge post 35 fixed to the outside of the fixed ring 31, when the linkage ring 33 rotates, it will push the hinge rod 36 to swing around the hinge post 35 through the sliding sleeve 37. The free end of the hinge rod 36 passes through the gap between the rotating ring 32 and the linkage ring 33 and is rotatably connected to the clamping plate 38. As the hinge rod 36 swings, the three clamping plates 38 arranged evenly in the circumference will converge towards the center, thereby evenly clamping the cable 4 from multiple directions to achieve reliable clamping and fixing.
[0045] Under the combined action of the rotating ring 32, the linkage ring 33 and the hinge rod 36, the three clamping discs 38 can converge evenly towards the center in the circumferential direction, applying a uniform radial clamping force to the cable 4, avoiding local indentation or damage to the cable 4 caused by excessive force at a single point, and at the same time greatly improving the clamping firmness.
[0046] Meanwhile, since the clamping disc 38 is rotatably connected to the hinge rod 36, the clamping disc 38 can make slight adjustments according to the surface contour of the cable 4 during the clamping process, so as to achieve adaptive fitting, improve friction and clamping stability, and effectively protect the outer sheath of the cable 4 from wear.
[0047] By controlling the rotation angle of the rotating ring 32 through the drive component 34, stepless adjustment of the clamping force can be achieved, which ensures that the clamping force is large enough to resist external tensile stress, while avoiding damage to the cable structure due to excessive clamping.
[0048] Furthermore, the drive assembly 34 includes a drive motor 342 and a lead screw 344. A hinge protrusion 345 is provided on the outer side of the rotating ring 32. A hinge block 341 is hingedly mounted on the hinge protrusion 345. A hinge block 343 is hingedly mounted on the fixed ring 31. One end of the lead screw 344 is threaded through the hinge block 341. The other end of the lead screw 344 rotates through the hinge block 343 and is then connected to the drive motor 342 for transmission.
[0049] Specifically, when it is necessary to drive the rotating ring 32 to rotate, the drive motor 342 is started. The drive motor 342 outputs power to drive the lead screw 344 to rotate. During the rotation of the lead screw 344, the first hinge block 341 will be displaced along the axial direction of the lead screw 344. Since the movement direction of the first hinge block 341 is constrained by the hinge protrusion 345, and the second hinge block 343 provides a stable rotation fulcrum for the lead screw 344, the linear motion of the first hinge block 341 will be converted into a tangential thrust on the rotating ring 32, thereby driving the rotating ring 32 to generate a stable rotational motion relative to the fixed ring 31, providing power for the subsequent clamping disc 38 to clamp the cable 4.
[0050] Example 3 Please see Figure 5 In this embodiment, the generator enclosed bus CT junction box is based on the above embodiment two. The fixing ring 31 is connected to the auxiliary junction box 2 through a number of connecting posts 311 evenly arranged in the circumferential direction. In addition, an inlet tube 312 sleeved on the cable 4 is provided between the fixing ring 31 and the inlet hole 24.
[0051] As can be seen from the above description, the fixing ring 31 is fixedly installed on the auxiliary junction box 2 by a number of connecting posts 311 evenly arranged in the circumferential direction, providing a stable installation base for the entire external clamping mechanism 3. At the same time, the cable inlet tube 312 provides guidance and protection for the cable inlet section 4.
[0052] Example 4 Please see Figure 6 and Figure 7 In this embodiment, the generator enclosed bus CT junction box, based on the above-mentioned Embodiment 1, Embodiment 2 or Embodiment 3, includes a sliding box 51 installed inside the auxiliary junction box 2 as the internal clamping mechanism 5.
[0053] In this embodiment, the auxiliary junction box 2 is provided with a sliding groove, and the bottom of the sliding box 51 is provided with a slider that is slidably installed in the sliding groove, so as to facilitate the adjustment of the position of the sliding box 51 and the overall position of the internal clamping mechanism 5 can be flexibly adjusted according to the actual cable 4's inlet direction and bending arc.
[0054] The top of the sliding box 51 is integrally connected to a connecting block 571. The free end of the connecting block 571 is integrally connected to a semi-circular upper collar 57. The bottom end of the upper collar 57 is provided with a lower collar 56 that cooperates with the upper collar 57 and is used to clamp the cable 4. The bottom end of the lower collar 56 is fixedly connected to an ejector slide rod 55. The sliding box 51 is equipped with a reset ejector mechanism for pushing the ejector slide rod 55 upward after the box cover 21 is locked.
[0055] In this embodiment, both the upper collar 57 and the lower collar 56 are made of elastic insulating material.
[0056] Specifically, the reset ejection mechanism includes a sliding rod 52, a top-connecting rod 53, and a sliding rod 54. The sliding box 51 is provided with a horizontal slot 512 and vertical slots 511 and 513, which are vertically intersecting at both ends of the horizontal slot 512. The sliding rod 52 is slidably installed in the vertical slot 511, the sliding rod 54 is slidably installed in the vertical slot 513, and the top-connecting rod 53 is slidably installed in the horizontal slot 512.
[0057] The top of the sliding rod 52 extends out of the vertical slot 511 and fits against the bottom of the box cover 21. The bottom of the sliding rod 52 has a mating slope 522. The bottom of the sliding rod 54 has a mating slope 541. One end of the top connecting rod 53 has a lifting slope 531 that abuts against the mating slope 522. The other end of the top connecting rod 53 has a lifting slope 532 that abuts against the mating slope 541.
[0058] The top end of the sliding insert rod 54 is fixedly connected to the bottom end of the ejector slide rod 55, and a spring 58 sleeved on the outside of the ejector slide rod 55 is connected between the top end of the sliding insert rod 54 and the top end inside the vertical slot 513.
[0059] As can be seen from the above description, when the lid 21 is in the open state, the spring 58 is in the extended state, pushing the sliding rod 2 54 downward. The mating slope 2 541 at the bottom of the sliding rod 2 54 pushes the top rod 53 to move closer to the sliding rod 1 52 in the horizontal slot 512 through the lifting slope 2 532 at the end of the top rod 53. The lifting slope 1 531 at the other end of the top rod 53 pushes the sliding rod 1 52 upward to extend it out of the vertical slot 1 511 through the mating slope 1 522 at the bottom of the sliding rod 1 52.
[0060] When the operator closes and locks the cover 21, the bottom of the cover 21 presses down on the top of the sliding rod 52, forcing the sliding rod 52 to slide downward against the spring force of the spring 58. The mating slope 522 at the bottom of the sliding rod 52 pushes the top rod 53 in the transverse slot 512 towards the sliding rod 54 through the lifting slope 531 of the top rod 53. The lifting slope 532 at the other end of the top rod 53 pushes the sliding rod 54 upward through the mating slope 541 at the bottom of the sliding rod 54. The top of the sliding rod 54 drives the ejector slide 55, which is fixedly connected to it, to move upward. The ejector slide 55 then pushes the lower collar 56 upward, so that the lower collar 56 and the upper collar 57 fixedly installed at the top of the sliding box 51 are engaged with each other, thereby tightly clamping the cable 4 passing between them.
[0061] When the cover 21 is opened again, the spring 58 returns to its original position, pushing the above-mentioned components to move in the opposite direction, and the lower collar 56 separates from the upper collar 57, releasing the cable 4.
[0062] Therefore, when maintenance personnel close and lock the cover 21, the internal clamping mechanism 5 automatically clamps the cable 4. When the cover 21 is opened, the clamping is automatically released, thus avoiding the risk of maintenance personnel forgetting to manually clamp or loosen the cable, and improving the reliability and safety of the operation.
[0063] Secondly, the cross-type transmission mechanism composed of sliding rod 1 52, top connecting rod 53, and sliding rod 2 54 transforms the vertical downward pressing motion of the cover 21 into the vertical lifting motion of the lower collar 56. The structure is compact, the transmission is reliable, and the limited space inside the sliding box 51 is fully utilized.
[0064] The upper collar 57 and the lower collar 56 are made of elastic insulating material. On the one hand, the elastic deformation ability of the material can adapt to the outer contour of the cable 4 when clamping, which not only ensures the clamping firmness, but also avoids the pressure mark damage to the cable 4 caused by rigid clamping. On the other hand, the insulating material can provide additional electrical isolation protection, further improving safety.
[0065] The spring 58 ensures that all components can reliably reset when the lid 21 is opened, preparing for the next clamping action, while also ensuring the smooth operation of the linkage mechanism and the accuracy of repeated positioning.
[0066] Furthermore, a pressure block 521 is fixedly connected to the top of the sliding rod 52. The pressure block 521 increases the contact area between the top of the sliding rod 52 and the cover 21, effectively dispersing the downward pressure generated when the cover 21 is locked. This avoids wear on the top of the sliding rod 52 or local indentations on the cover 21 caused by long-term point contact or small area force, thus improving the service life of the components.
[0067] The working principle of the present invention is as follows: During operation, the cable 4 is first introduced through the inlet hole 24 on the side of the auxiliary junction box 2. After entering the auxiliary junction box 2, the cable 4 is bent downwards and then passes through the junction tube 11 that is connected to the top of the main junction box 1. Finally, it enters the main junction box 1 to complete the electrical connection with the CT.
[0068] During this process, cable 4 needs to pass through two key locations in sequence: At the position where the cable enters the inlet hole 24, the external clamping mechanism 3 installed on the outer wall of the secondary junction box 2 initially clamps and fixes the cable 4 to eliminate the pulling force from the outside.
[0069] Subsequently, inside the secondary junction box 2, the internal clamping mechanism 5 clamps the cable 4 again.
[0070] Through the coordinated action of the external clamping mechanism 3 and the internal clamping mechanism 5, the cable 4 is reliably positioned at the inlet hole 24 and inside the secondary junction box 2. This effectively distributes and bears the gravity and external tension that might have directly acted on the terminals inside the main junction box 1 onto the secondary junction box 2, the external clamping mechanism 3, and the internal clamping mechanism 5, ensuring that the cable segment entering the main junction box 1 is in a stress-free or low-stress state.
[0071] In the description of this invention, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. 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.
[0072] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0073] Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
Claims
1. A generator enclosed busbar CT junction box, comprising a main junction box (1), characterized in that: The top of the main junction box (1) is connected to a junction tube (11), and the top of the junction tube (11) is connected to a secondary junction box (2). The secondary junction box (2) has an inlet hole (24) on its side. One of the terminals of the cable (4) enters the interior of the secondary junction box (2) through the inlet hole (24), bends downward, passes through the junction tube (11), and enters the interior of the main junction box (1). An external clamping mechanism (3) for clamping the cable (4) is provided at the inlet hole (24) and installed on the outer wall of the sub-junction box (2). An internal clamping mechanism (5) for clamping the cable (4) is provided inside the sub-junction box (2).
2. The generator enclosed busbar CT junction box according to claim 1, characterized in that: The external clamping mechanism (3) includes a fixed ring (31), a rotating ring (32) is concentrically mounted on the outside of the fixed ring (31), and a linkage ring (33) is concentrically spaced on the outside of the rotating ring (32). A plurality of hinged columns (35) are also fixed on the outside of the fixed ring (31) and evenly arranged in the circumferential direction. A hinged rod (36) is hinged to the free end of the hinged column (35). The free end of the hinged rod (36) passes through the gap between the rotating ring (32) and the linkage ring (33) and is rotatably connected to a clamping disc (38). A sliding sleeve (37) is also slidably sleeved on the hinged rod (36), and the sliding sleeve (37) is hinged on the linkage ring (33). A drive assembly (34) for driving the rotating ring (32) to rotate is also provided on the outside of the fixed ring (31).
3. The generator enclosed busbar CT junction box according to claim 2, characterized in that: The drive assembly (34) includes a drive motor (342) and a lead screw (344). A hinge protrusion (345) is provided on the outer side of the rotating ring (32). A hinge block one (341) is hinged on the hinge protrusion (345). A hinge block two (343) is hinged on the fixed ring (31). One end of the lead screw (344) is threaded through the hinge block one (341). The other end of the lead screw (344) rotates through the hinge block two (343) and is then connected to the drive motor (342) for transmission.
4. The generator enclosed busbar CT junction box according to claim 2, characterized in that: The fixing ring (31) is connected to the auxiliary junction box (2) through a number of connecting posts (311) evenly arranged in the circumferential direction, and an inlet tube (312) sleeved on the cable (4) is also provided between the fixing ring (31) and the inlet hole (24).
5. A generator enclosed busbar CT junction box according to claim 1, characterized in that: The top of the secondary junction box (2) is detachably provided with a cover (21). There are plugs (23) inserted at the four corners of the cover (21). The bottom of the plugs (23) passes through the cover (21) and the secondary junction box (2) in sequence and is detachably connected to the main junction box (1). The top of the plugs (23) is locked by a lock nut (22).
6. A generator enclosed busbar CT junction box according to claim 5, characterized in that: The internal clamping mechanism (5) includes a sliding box (51) installed inside the sub-junction box (2). A connecting block (571) is integrally connected to the top of the sliding box (51). A semi-circular upper collar (57) is integrally connected to the free end of the connecting block (571). A lower collar (56) is provided at the bottom of the upper collar (57) to cooperate with the upper collar (57) and to clamp the cable (4). A push-out slide rod (55) is fixedly connected to the bottom of the lower collar (56). A reset push-out mechanism is installed inside the sliding box (51) to push the push-out slide rod (55) upward after the box cover (21) is locked.
7. A generator enclosed busbar CT junction box according to claim 6, characterized in that: The reset ejection mechanism includes a sliding rod one (52), a top-connecting rod (53), and a sliding rod two (54). The sliding box (51) is provided with a horizontal transverse slot (512) and vertical slot one (511) and vertical slot two (513) vertically intersecting at both ends of the transverse slot (512). The sliding rod one (52) is slidably installed in the vertical slot one (511), the sliding rod two (54) is slidably installed in the vertical slot two (513), and the top-connecting rod (53) is slidably installed in the transverse slot (512). The top of the sliding rod (52) extends out of the vertical slot (511) and fits the bottom of the box cover (21). The bottom of the sliding rod (52) is provided with a mating slope (522). The bottom of the sliding rod (54) is provided with a mating slope (541). One end of the top-connecting rod (53) is provided with a lifting slope (531) that abuts against the mating slope (522). The other end of the top-connecting rod (53) is provided with a lifting slope (532) that abuts against the mating slope (541). The top end of the sliding insert rod (54) is fixedly connected to the bottom end of the ejector slide rod (55), and a spring (58) sleeved on the outside of the ejector slide rod (55) is connected between the top end of the sliding insert rod (54) and the top end inside the vertical slot (513).
8. A generator enclosed busbar CT junction box according to claim 7, characterized in that: The top end of the sliding insert (52) is fixedly connected to a pressure block (521).
9. A generator enclosed busbar CT junction box according to claim 1, characterized in that: Sealing rings are provided at the connection points between the junction box (11) and the main junction box (1) and the auxiliary junction box (2).
10. A generator enclosed busbar CT junction box according to claim 1, characterized in that: The inlet hole (24) is located in the middle of the side of the auxiliary junction box (2).