Ring main unit and interlocking device thereof

Abstract

The utility model relates to a ring main unit and interlock device thereof. The ring main unit comprises a three-position mechanism, a three-position switch and a circuit breaker mechanism in a cabinet. The interlock device comprises a first interlock module on the side of the three-position mechanism, a second interlock module on the side of the cable chamber door and a third interlock module on the side of the circuit breaker mechanism. The first interlock module is connected to the second interlock module through a first transmission member, connected to the third interlock module through a second transmission member and a third transmission member, and connected to the output shaft of the circuit breaker through a fourth transmission member, so as to realize a five-prevention interlock mechanism.

Description

Technical Field

[0001] This utility model relates to medium-voltage switchgear, and more particularly to ring main units and their interlocking devices. Background Technology

[0002] Ring main units (RNBs) are switchgear used in ring main power supply systems. In recent years, with increasingly stringent environmental protection requirements, RNBs have continuously evolved in terms of technology and product form, gradually developing into medium-voltage switchgear that uses environmentally friendly gases (mainly dry air or nitrogen) as the insulating medium—these are known as environmentally friendly switchgear. However, in existing technologies, the isolation interlocking devices used in environmentally friendly switchgear still have some shortcomings. For example, because the interlocking design needs to simultaneously cover the three-position mechanism and the circuit breaker mechanism, the sheet metal parts involved have larger structural dimensions, relatively lower flatness and strength, and inconsistent assembly standards. Furthermore, during production line assembly and transportation, parts are easily deformed by impacts or vibrations, leading to problems such as jamming of the interlocking mechanism, reduced flexibility, and unreliable electrical switching.

[0003] Therefore, the industry urgently needs to optimize and improve existing interlocking devices to enhance assembly convenience, interlocking reliability, and electrical switching stability. Utility Model Content

[0004] The present invention aims to provide an interlocking device for a ring main unit, which at least solves some of the above-mentioned technical problems.

[0005] This utility model also aims to provide a ring main unit that applies the above-mentioned improved interlocking device.

[0006] According to one aspect of the present invention, an interlocking device for a ring main unit is provided, the ring main unit comprising: a cabinet defining a cable compartment, the cable compartment being equipped with an openable and closable cable compartment door; a three-position mechanism and a three-position switch installed in the cabinet, the three-position switch having a main contact movable between a closed position, an isolated position, and a grounded position, the three-position mechanism including a first output shaft connected to the main contact, and a closing operation shaft and a grounding operation shaft driving the first output shaft; and a circuit breaker mechanism installed in the cabinet, including a second output shaft, and a closing mechanism and a opening mechanism driving the second output shaft. The interlocking device includes: a first interlocking module installed in the cabinet near the three-position mechanism; a second interlocking module connected to the cable compartment door and connected to the first interlocking module via a first transmission component; and a third interlocking module installed in the cabinet near the circuit breaker mechanism and connected to the first interlocking module via a second transmission component and a third transmission component, respectively. When the cable compartment door is closed, the second interlocking module drives the first interlocking module to move linearly away from the first output shaft via the first transmission component, allowing the first output shaft to rotate and drive the main contact to move towards the closed or isolated position. When the main contact moves to the closed or isolated position, the first interlocking module is restricted to linear movement towards the first output shaft to keep the cable compartment door closed. When the circuit breaker mechanism opens, the second interlocking module is locked by the second output shaft to keep the cable compartment door closed. The cable compartment door remains closed. When the main contact moves to the grounding position and the circuit breaker mechanism closes, the first interlocking module is released to allow the cable compartment door to open, while the second interlocking module locks the opening mechanism. When the main contact is in the isolation position, the first interlocking module drives the third interlocking module to move to lock the closing mechanism via the second transmission component. The first interlocking module is also connected to the second output shaft via the fourth transmission component. When the circuit breaker mechanism opens, the second output shaft drives the first interlocking module to move away from the closing operation shaft and the grounding operation shaft via the fourth transmission component. The first interlocking module automatically resets and locks the closing operation shaft and the grounding operation shaft when the circuit breaker mechanism closes. When the closing operation shaft and the grounding operation shaft are allowed to operate, the first interlocking module drives the third interlocking module to move to lock the closing mechanism via the third transmission component.

[0007] The interlocking device provided in this solution decomposes complex interlocking logic into a clear modular structure by setting up three functionally defined and interrelated interlocking modules. This design simplifies the structure and overall assembly relationship. The interlocking components can use small molded parts, achieving high integration and helping to standardize part dimensions, thereby reducing assembly difficulty and costs. Power transmission and coupling between modules are achieved through a single transmission component (e.g., a pull rod or pull plate). This mechanical transmission method is direct and reliable, optimizing the force transmission path and offering greater tolerance, facilitating the adjustment of assembly errors between modules and ensuring smooth and highly reliable interlocking action. The interlocking device in this solution is fully functional, achieving tight mechanical interlocking between the three-position mechanism, the circuit breaker mechanism, and the cable compartment door, preventing operators from accidentally entering live compartments. This comprehensive and logically rigorous interlocking mechanism greatly improves the safety of equipment operation and eliminates the possibility of misoperation. The modular design makes the structure of each functional unit more compact and targeted, helping to design better structural strength and operational stability for key components, improving the reliability of equipment during long-term operation.

[0008] In some embodiments, the first interlocking module includes: a cam engaged with the first output shaft; a movable rod capable of linear movement toward or away from the first output shaft, the movable rod being rigidly connected to one end of the first transmission member; and a return spring connected to the movable rod and applying a force to the movable rod to cause it to move linearly toward the first output shaft.

[0009] In some embodiments, the second interlocking module includes: a sliding frame rigidly connected to the other end of the first transmission member, the sliding frame having a limiting groove and an elongated groove extending at an angle relative to its sliding direction; a stop cam pivotally disposed within the cabinet and provided with a rod, the rod being inserted into the elongated groove of the sliding frame and movable along the elongated groove; and a hanging rod detachably connected to the cable compartment door and provided with a limiting rod inserted into the limiting groove of the sliding frame; wherein, the cable compartment door moving in the closing direction drives the sliding frame via the hanging rod, and the sliding frame drives the movable rod to move linearly in a direction away from the first output shaft via the first transmission member, so as to allow the first output shaft to drive the main contact to move toward the closing position or the isolation position; when the main contact moves to the closing position or the isolation position, the cam presses against the movable rod and restricts the movable rod to move linearly in a direction close to the first output shaft, so as to keep the cable compartment door in a closed state; when the first output shaft drives the main contact to move toward the grounding position, the cam moves away from the movable rod.

[0010] In some embodiments, the second output shaft of the circuit breaker mechanism is connected to a radially extending top plate. When the circuit breaker mechanism is tripped, the second output shaft rotates to press the top plate against the sliding frame to keep the cable compartment door closed.

[0011] In some embodiments, the tripping mechanism of the circuit breaker includes a pivotable tripping drive shaft and a tripping plate engaged with the tripping drive shaft. When the cable compartment door is closed in the position, the sliding frame releases the tripping plate to allow the circuit breaker to trip, and when the cable compartment door moves in the opening direction, the sliding frame locks the tripping plate to restrict the tripping of the circuit breaker.

[0012] In some embodiments, a door-closing microswitch is mounted adjacent to the movable rod, which is triggered by the movable rod moving away from the first output shaft to provide a signal.

[0013] In some embodiments, the first interlocking module includes a crank arm engaged with the first output shaft, and the third interlocking module includes a pivotable first interlocking baffle having a first arcuate groove. One end of the second transmission member is connected to the crank arm, and the other end is inserted into the first arcuate groove and can move along the first arcuate groove. When the main contact is in the isolation position, the crank arm drives the first interlocking baffle to pivot to lock the closing mechanism through the second transmission member, thereby restricting the closing of the circuit breaker mechanism.

[0014] In some embodiments, the first interlocking module includes: a first interlocking assembly disposed near the grounding operating shaft and including a first latch and a first rotating member, wherein the first latch is driven to pivot the first rotating member during grounding handle operation of the grounding operating shaft; a second interlocking assembly disposed near the closing operating shaft and including a second latch and a second rotating member, wherein the second latch is driven to pivot the second rotating member during closing handle operation of the closing operating shaft, wherein one of the first rotating member and the second rotating member is connected to one end of the third transmission member; and a connecting rod connected between the first rotating member and the second rotating member.

[0015] In some embodiments, the first rotating member and the second rotating member each include: a shaft pivotally disposed within the cabinet; an arm extending radially from the shaft and having a spaced-apart first and second opening, one of the first and second openings for mounting the connecting rod and the other for mounting the third transmission member; and a ridge extending from the shaft, gradually approaching the corresponding latch along the operating direction of the closing handle or the grounding handle.

[0016] In some embodiments, a grounding microswitch is installed adjacent to the first actuator, which drives the first actuator and triggers the grounding microswitch to provide a signal during grounding operation shaft operation by the grounding handle; a closing microswitch is installed adjacent to the second actuator, which drives the second actuator and triggers the closing microswitch to provide a signal during closing operation shaft operation by the closing handle.

[0017] In some embodiments, the third interlocking module includes a pivotable second interlocking baffle with a second arcuate groove. A pin fixed to the cabinet body passes through the second arcuate groove and is movable along the second arcuate groove. The second interlocking baffle is connected to the other end of the third transmission member. During the operation of the closing operating shaft by the closing handle or the operation of the grounding operating shaft by the grounding handle, the first interlocking module drives the second interlocking baffle to pivot and lock the closing mechanism to restrict the closing of the circuit breaker mechanism.

[0018] In some embodiments, the first interlocking module includes a movable interlocking cover plate, the second output shaft of the circuit breaker mechanism is connected to a radially extending top plate, one end of the fourth transmission member is connected to the top plate and the other end is connected to the interlocking cover plate, and during the opening of the circuit breaker mechanism, the top plate drives the interlocking cover plate away from the closing operation shaft and the grounding operation shaft through the fourth transmission member.

[0019] According to another aspect of this utility model, a ring main unit is provided, comprising: a cabinet defining a cable compartment, the cable compartment being equipped with an openable and closable cable compartment door; a three-position mechanism and a three-position switch installed in the cabinet, the three-position switch having a main contact movable between a closed position, an isolated position, and a grounded position, the three-position mechanism including a first output shaft connected to the main contact, and a closing operation shaft and a grounding operation shaft driving the first output shaft; a circuit breaker mechanism installed in the cabinet, including a second output shaft, and a closing mechanism and a opening mechanism driving the second output shaft; the ring main unit further includes the aforementioned interlocking device.

[0020] Other features and advantages of this invention will partly be apparent to those skilled in the art upon reading this application, and partly will be described below in conjunction with the accompanying drawings in the detailed description. Attached Figure Description

[0021] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings, wherein:

[0022] Figure 1 This is a schematic diagram of a ring main unit interlocking device according to an embodiment of the present utility model;

[0023] Figure 2 This is a schematic diagram of the interlocking device according to an embodiment of the present invention, showing the interlocking between the three-position switch and the cable compartment door;

[0024] Figure 3 and Figure 4 This is a schematic diagram of the second interlocking module in the interlocking device according to an embodiment of the present invention at different angles;

[0025] Figure 5 This is a schematic diagram of the interlocking device of the three-position switch and the circuit breaker according to an embodiment of the present utility model;

[0026] Figure 6 This is a schematic diagram illustrating the operation of the three-position switch and the interlocking with the circuit breaker in the interlocking device according to an embodiment of the present invention.

[0027] Figure 7 This is an assembly diagram of the latch, sliding shaft and electrical switch in the interlocking device according to an embodiment of the present invention;

[0028] Figure 8 This is an assembly diagram of the second interlocking module and the interlocking cover plate in the interlocking device according to an embodiment of the present utility model;

[0029] Figure 9 This is a schematic diagram of the status indicator of the three-station mechanism in the interlocking device according to an embodiment of the present utility model.

[0030] Explanation of reference numerals in the attached figures

[0031] 1-Three-position mechanism; 11-First bracket; 121-Fixing plate; 12-Closing operation shaft; 13-Grounding operation shaft; 14-First output shaft; 15-Closing handle; 16-Grounding handle; 17-Indicator sign; 171-Through hole; 172-Handle; 2-Circuit breaker mechanism; 21-Second bracket; 22-Closing lever; 23-Closing drive shaft; 24-Spring; 25-Top plate; 26-Second output shaft; 3-Cable compartment door; 4-First interlocking module; 40-Cam; 41-Crank arm; 42-Moving rod; 421-Reset spring; 43-Door closing micro switch; 44-Interlocking cover plate; 41-Through hole; 442-Long slot; 45-First interlocking assembly; 451-First lever; 452-First rotating component; 46-Second interlocking assembly; 461-Second lever; 462-Second rotating component ; 463-Shaft; 464-Arm; 465-First Orifice; 466-Second Orifice; 467-Sloping Ridge; 47-Close Microswitch; 48-Grounding Microswitch; 49-Connecting Rod; 5-Second Interlocking Module; 51-Hanging Rod; 511-Limit Rod; 52-Fixing Frame; 521-First Slide Groove; 522-Second Slide Groove; 53-Sliding Frame; 531-Long Groove; 532-Ring Member; 53 3-Limiting groove; 54-Stop cam; 541-Pivot; 542-Rod; 6-Third interlocking module; 61-First interlocking baffle; 611-First hole; 612-First arc-shaped groove; 62-Second interlocking baffle; 621-Second hole; 622-Second arc-shaped groove; 63-Pin; 100-First transmission component; 200-Second transmission component; 300-Third transmission component; 400-Fourth transmission component Detailed Implementation

[0032] The schematic solutions of the technical solutions disclosed in this utility model are now described in detail with reference to the accompanying drawings. Although the drawings are provided to illustrate some embodiments of this utility model, the drawings are not necessarily drawn to the dimensions of the specific embodiments, and certain features may be enlarged, removed, or partially cut to better illustrate and explain the disclosure of this utility model. Some components in the drawings may be repositioned according to actual needs without affecting the technical effect. The phrase "in the drawings" or similar terms appearing in the specification do not necessarily refer to all drawings or examples.

[0033] Certain directional terms used in the description of the accompanying drawings below, such as “inner,” “outer,” “above,” “below,” and other directional terms, will be understood to have their normal meaning and refer to those directions as normally viewed in the accompanying drawings. Unless otherwise specified, the directional terms used in this specification are generally in accordance with the conventional directions understood by those skilled in the art.

[0034] The terms “first,” “first,” “second,” “second,” and similar terms used in this utility model do not indicate any order, quantity, or importance, but are used to distinguish one component from other components.

[0035] The modular interlocking device provided by this utility model is applied to ring main units, especially environmental protection units. The ring main unit has multiple compartments within its metal cabinet, separated by partitions, for accommodating electrical devices such as three-position mechanisms, three-position switches, circuit breaker mechanisms, and busbars. The three-position mechanism is the operating mechanism for the three-position switch. The main contacts of the three-position switch can move between the closed position, the isolated position, and the grounded position under the drive of the three-position mechanism. One compartment within the cabinet is a cable compartment, which is equipped with an openable and closable door.

[0036] Figures 1 to 8 A partial view of the cabinet interior of a ring main unit is illustrated. As shown, the three-position mechanism 1 is mounted to a first bracket 11, which can be a metal partition inside the cabinet or part of the cabinet wall. The first output shaft 14, closing operation shaft 12, and grounding operation shaft 13 of the three-position mechanism 1 are mounted parallel to each other and spaced apart on the first bracket 11, and each can pivot about its own central axis. The first output shaft 14 is connected to the main contacts of the three-position switch. In the illustrated embodiment, the closing operation shaft 12 and the grounding operation shaft 13 are arranged vertically, while the first output shaft 14 is located on one side of them and between them in height. The closing operation shaft 12 and the grounding operation shaft 13 can respectively drive the first output shaft 14 to pivot, thereby driving the main contacts of the three-position switch to switch between the closed position, the isolated position, and the grounded position. Figure 9 The three-position status indicator 17 shown is mounted on the first output shaft 14, for example, by passing the first output shaft 14 through the through hole 171 of the indicator 17. The indicator 17 can move synchronously with the rotation of the first output shaft 14.

[0037] The circuit breaker mechanism 2 is mounted to the second bracket 21 on one side of the three-position mechanism 1, which is located below the three-position mechanism 1 in the illustrated embodiment. The second bracket 21 can be a metal partition inside the cabinet or part of the cabinet wall. The second output shaft 26, closing drive shaft 23, and opening drive shaft (not shown) of the circuit breaker mechanism 2 are mounted parallel to each other and spaced apart on the second bracket 21, and each can pivot about its own central axis. In the illustrated embodiment, the second output shaft 26 is located between the closing drive shaft 23 and the opening drive shaft. The second output shaft 26 is connected to the moving contact of the circuit breaker mechanism 2. A radially extending closing rod 22 is fixedly mounted on the closing drive shaft 23. A spring 24 is sleeved on the closing drive shaft 23 and provides a restoring force. Rotating the closing rod 22 to drive the closing drive shaft 23 to pivot can further drive the second output shaft 26 to rotate in the closing direction, thereby causing the moving contact to approach the stationary contact, realizing the closing of the circuit breaker mechanism 2. When circuit breaker mechanism 2 is tripped, the closing drive shaft 23 can automatically reset under the action of spring 24. A radially extending tripping plate is mounted on the tripping drive shaft of circuit breaker mechanism 2. Rotating the tripping plate drives the tripping drive shaft to pivot, which further drives the second output shaft 26 to rotate in the tripping direction, thereby moving the moving contact away from the stationary contact and realizing the tripping of circuit breaker mechanism 2. When circuit breaker mechanism 2 is closed, the tripping drive shaft can automatically reset under the action of its own reset spring.

[0038] The cable compartment door 3 and the three-position mechanism 1 are located on opposite sides of the circuit breaker mechanism 2. Driving the cable compartment door 3 away from the three-position mechanism 1 and the circuit breaker mechanism 2 closes the cable compartment. Driving the cable compartment door 3 towards the three-position mechanism 1 and the circuit breaker mechanism 2 opens the cable compartment. In the illustrated embodiment, the cable compartment door 3 is located below the circuit breaker mechanism 2; vertical downward movement of the cable compartment door 3 closes the cable compartment, while vertical upward movement opens the cable compartment.

[0039] The interlocking device is divided into three modules according to function and area: the first interlocking module 4 on the three-position mechanism side, the second interlocking module 5 on the cable compartment door side, and the third interlocking module 6 on the circuit breaker mechanism side. The three modules are connected by a single longitudinal transmission component, such as a connecting plate or tie rod, to achieve force transmission and establish an interlocking mechanism. The three interlocking modules are described below with reference to the accompanying drawings.

[0040] First interlocking module

[0041] The first interlocking module 4 is installed close to the three-station mechanism 1. In the first interlocking module 4, the cam 40 and the crank arm 41 are respectively sleeved on the first output shaft 14 of the three-station mechanism 1 and arranged radially at intervals along the first output shaft 14. Figure 2As shown, the movable rod 42, which is associated with the cam 40 in terms of position and motion, can move linearly to approach or move away from the first output shaft 14. To mount the movable rod 42, a mounting bracket 121 can be installed on the first support 11. This mounting bracket 121 has an opening through which the movable rod 42 passes, thereby defining the movement trajectory of the movable rod 42. A lateral cantilever can be formed at the end of the movable rod 42 near the first output shaft 14. This lateral cantilever can both form a stop around the opening of the mounting bracket 121 to limit the travel of the movable rod 42 and also serve as a limiting element that cooperates with the cam 40.

[0042] When the cable compartment door 3 is closed, the movable member 42 can be driven by the second interlocking module 5, which will be described in detail later, to move linearly away from the first output shaft 14, thereby clearing the rotation path of the cam 40 to allow the first output shaft 14 to drive the main contact of the three-position switch to move to the closed or isolated position. When the main contact moves to the closed or isolated position, the cam 40 rotates to a position that abuts against the movable rod 42 from the side of the movable rod 42 facing away from the cable compartment door 3 to prevent the movable rod 42 from resetting. In the illustrated embodiment, when the main contact moves to the closed or isolated position, the cam 40 rotates to a position where its convex arc edge presses against the top surface of the transverse cantilever of the movable rod 42, preventing the movable rod 42 from moving linearly towards the first output shaft 14 and resetting under the action of the return spring 421, thus keeping the cable compartment door 3 in the closed state. When the first output shaft 14 drives the main contact of the three-position switch to move toward the ground position, the cam 40 moves synchronously and moves away from the movable rod 42. At this time, the movable rod 42 tends to move closer to the first output shaft 14 under the drive of the reset spring 421 to reset.

[0043] The closing operation shaft 12 and the grounding operation shaft 13 of the three-position mechanism 1 can pass through the fixing frame 121 respectively, and their respective extended front ends of the fixing frame 121 can serve as operating ends for engaging the closing handle 15 and the grounding handle 16 respectively. Interlocking components are provided for the closing operation shaft 12 and the grounding operation shaft 13 respectively. For clarity, the interlocking component corresponding to the upper grounding operation shaft 13 is defined as the first interlocking component 45, and the interlocking component corresponding to the lower closing operation shaft 12 is defined as the second interlocking component 46. The first interlocking component 45 and the second interlocking component 46 can have the same or similar structures. As shown in the figure, the first interlocking component 45 includes a first latch 451 and a first rotating member 452 mounted on the fixing frame 121. The first latch 451 can move axially along the grounding operation shaft 13. The first rotating member 452 can rotate under the drive of the first latch 451. The second interlocking component 46 includes a second latch 461 and a second rotating member 462 mounted on the fixing frame 121. The second actuator 461 can move axially along the closing operation shaft 12. The second rotating component 462 can rotate under the drive of the second actuator 461.

[0044] Since the first interlocking component 45 and the second interlocking component 46 in this embodiment adopt basically the same structure, therefore Figure 7 The second interlocking assembly 46 is shown only as an example for reference. As shown, the front end of the second latch 461 can extend from the mounting bracket 121. The closing handle 15 can be fitted onto the operating end of the closing operating shaft 12 and moved axially along the closing operating shaft 12 a certain unlocking distance. Afterward, rotating the closing handle 15 can drive the closing operating shaft 12 to rotate synchronously. When the closing handle 15 moves axially along the closing operating shaft 12, the second latch 461 can be synchronously pushed to move axially along the closing operating shaft 12. The second rotating member 462 is a one-piece molded part, and the two ends of its shaft 463 can be used to fit a mounting bracket and connect the mounting bracket to the mounting bracket 121. An arm 464 can be integrally extended from approximately the middle position of the shaft 463. The arm 464 has openings formed at two spaced-apart positions, including a first opening 465 near the shaft 463 and a second opening 466 away from the shaft 463. Adjacent to arm 464, a ridge 467 extends integrally from shaft 463. This ridge 467 gradually approaches the second latch 461 from front to back, such that the distance between the ridge 467 and the second latch 461 gradually decreases towards the rear end of the second latch 461. Therefore, when the closing handle 15 pushes the second latch 461, the second latch 461 simultaneously pushes the second rotating member 462 to rotate around the central axis of shaft 463.

[0045] A grounding microswitch 48 can be installed near the first latch 451. When the first latch 451 is pushed by the grounding handle 16, the grounding microswitch 48 can be triggered to send a signal, which is then fed into the closing circuit of the circuit breaker mechanism. Similarly, a closing microswitch 47 can be installed near the second latch 461. When the second latch 461 is pushed by the closing handle 15, the closing microswitch 47 can be triggered to send a signal, which is then fed into the closing circuit of the circuit breaker mechanism.

[0046] The first interlocking assembly 45 and the second interlocking assembly 46 can be linked together by a connecting rod 49 connecting the first rotating member 452 and the second rotating member 462. In the illustrated embodiment, one end of the connecting rod 49 is inserted into the first hole of the upper first rotating member 452, and the lower end of the connecting rod 49 is inserted into the first hole 465 of the lower second rotating member 462, so as to realize the force transmission between the two rotating members.

[0047] An interlocking cover plate 44 is also installed on the mounting bracket 121. The interlocking cover plate 44 can move to lock the closing operating shaft 12 and the grounding operating shaft 13, for example, by blocking their operation from the operator's operation via a handle. The interlocking cover plate 44 can also move away from the closing operating shaft 12 and the grounding operating shaft 13, allowing the operator to operate the corresponding operating shaft via a handle. A groove extending along the direction of movement of the interlocking cover plate 44 can be formed on the mounting bracket 121, and a pin can be installed on the interlocking cover plate 44. By inserting the pin into the groove, the interlocking cover plate 44 can move along the path defined by the groove. Alternatively, the groove can be formed on the interlocking cover plate, and the pin can be installed on the mounting bracket 121. Figure 8 An example is shown of a through hole 441 formed in the interlocking cover plate 44 for mounting a pin.

[0048] The interlocking cover plate 44 also has a long groove 442 extending along its direction of movement. One end of the fourth transmission member 400, which is configured as a pull rod, is inserted into the long groove 442 of the interlocking cover plate 44 and can move along the long groove 442. The other end of the fourth transmission member 400 is inserted into the through hole of the top plate 25 on the second output shaft 26 of the circuit breaker mechanism 2, thereby establishing an interlock between the opening and closing state of the circuit breaker mechanism 2 and the operating shaft of the three-position mechanism 1 by the fourth transmission member 400.

[0049] Specifically, when circuit breaker mechanism 2 trips, the second output shaft 26 rotates counterclockwise in the tripping direction shown in the figure, causing the top plate 25 to press down. The top plate 25 pulls the interlock cover plate 44 vertically downwards via the fourth transmission component 400, thereby exposing the closing operating shaft 12 and the grounding operating shaft 13. At this time, the operator can operate the closing operating shaft 12 or the grounding operating shaft 13 using the closing handle 15 or the grounding handle 16. When circuit breaker mechanism 2 closes, the interlock cover plate 44 can automatically move upwards by means of the return spring connected between it and the fixed frame 121, and once again block the front of the closing operating shaft 12 and the grounding operating shaft 13, prohibiting the operator from operating any operating shaft of the three-position mechanism 1 during the closing of circuit breaker mechanism 2.

[0050] As previously described, a three-position status indicator 17 may also be provided on the first output shaft 14 of the three-position mechanism 1. When the first output shaft 14 drives the main contact of the three-position switch to move to the isolation position, the indicator 17 moves with the first output shaft 14, causing the radially extending handle 172 of the indicator 17 to move between the closing operation shaft 12 and the grounding operation shaft 13, thus exposing both the closing operation shaft 12 and the grounding operation shaft 13 simultaneously. When the first output shaft 14 drives the main contact of the three-position switch to move to the closing position, the indicator 17 moves with the first output shaft 14 until the handle 172 blocks the grounding operation shaft 13, thereby limiting the operation of the grounding operation shaft 13 during the closing of the three-position switch. When the first output shaft 14 drives the main contact of the three-position switch to move to the grounding position, the indicator 17 moves with the first output shaft 14 until the handle 172 blocks the closing operation shaft 12, thereby limiting the operation of the closing operation shaft 12 during the grounding of the three-position switch.

[0051] Second interlocking module

[0052] The second interlocking module 5 is installed near the cable compartment door 3. In the second interlocking module 5, a longitudinally elongated hanging rod 51 movably passes through a fixing frame 52, its length direction corresponding to the movement direction of the cable compartment door 3. One end of the hanging rod 51 is detachably connected to the cable compartment door 3, and the other end extends away from the cable compartment door 3. The fixing frame 52 may be part of a fixed partition or frame inside the cabinet. A limiting rod 511 is installed on the hanging rod 51, extending at an angle to the hanging rod 51 (e.g., perpendicular to the length direction of the hanging rod 51). The limiting rod 511 passes through a first sliding groove 521 on the fixing frame 52 that extends along the length direction of the hanging rod 51, and can move along the first sliding groove 521. A sliding frame 53 is movably installed to the fixing frame 52 along the length direction of the hanging rod 51. In one embodiment, the fixing frame 52 forms a second sliding groove 522 extending along the length direction of the hanging rod 51, and the sliding frame 52 is provided with a rod 532. By inserting the rod 532 into the second groove 522, the sliding frame 53 can move along the path defined by the second groove 522. Alternatively, the second groove can be formed on the sliding frame 53, and the rod can be mounted on the fixed frame 52. The limiting rod 511 on the hanging rod 51 passes through the first groove 521 of the fixed frame 52 and is inserted into the limiting groove 533 of the sliding frame 53. The limiting groove 533 is open on the side opposite to the cable compartment door 3, thereby allowing the limiting rod 511 to move out of the receiving groove 533.

[0053] The second interlocking module 5 also includes a stop cam 54 pivotable about a pivot 541 mounted to the fixed frame 52, the stop cam 54 having a rod 542. The sliding frame 52 has an elongated slot 531 extending at an angle to its direction of movement (e.g., perpendicular to the direction of movement of the sliding frame 52). The rod 542 of the stop cam 54 passes through the elongated slot 531 of the sliding frame 53 and can move along the elongated slot 531. By moving the sliding frame 53, the stop cam 54 can be driven to rotate about the pivot 541, thereby suspending its protruding arcuate edge on the side of the limit rod 511 facing away from the cable compartment door 3, or the stop cam 54 can be driven to rotate about the pivot 541 to move away from the limit rod 511.

[0054] The sliding frame 53 is rigidly connected to one end of the first transmission member 100, which is configured as a connecting plate, while the other end of the first transmission member 100 is rigidly connected to the end of the movable rod 42 of the first interlocking module 4. Thus, the first transmission member 100 establishes an interlock between the state of the three-position switch and the opening and closing of the cable compartment door 3.

[0055] Specifically, when the cable compartment door 3 is closed, for example, when the cable compartment door 3 is pulled vertically downward in the illustrated embodiment, the cable compartment door 3 drives the hanging rod 51 of the second interlocking module 5 to move vertically downward, and the hanging rod 51 drives the sliding member 53 to move synchronously through the limiting rod 511. The sliding member 53 drives the first transmission member 100 to move vertically downward, thereby driving the movable rod 42 of the first interlocking module 4 to move linearly downward away from the first output shaft 14, clearing the rotation path of the cam 40. At this time, the main contact can be driven to move to the closed position or the isolated position through the first output shaft 14. When the main contact moves to the closed position or the isolated position, the cam 40 presses the movable rod 42 with its convex arc edge, preventing the movable rod 42 from moving upward to reset under the drive of the return spring 421. The downward movement of the movable rod 42 will trigger the door closing micro switch 43 installed on the fixed frame 121, providing a signal that the cable compartment door 3 is closed. As the sliding member 53 moves downwards with the cable compartment door 3 closing, the stop cam 54 is driven by the sliding member 53 to pivot and hover above the limit rod 511 with its outwardly convex arc edge, thereby blocking the upward movement of the limit rod 511. When the cable compartment door 3 is fully closed, if it is subjected to an upward opening force, the stop cam 54 will prevent the limit rod 511 from opening accidentally. In addition, the external force will hardly be fed back to the sliding frame 53 or even the first transmission member 100, so the other interlocking parts will not be impacted by external forces.

[0056] When the main contact of the three-position mechanism 1 is in the grounded position, the first output shaft 14 rotates to move the cam 40 away from the movable rod 42. At this time, as mentioned earlier, the movable rod 42 tends to move upward linearly under the action of the return spring 421 to reset. Whether the movable rod 42 can move upward to reset depends on the state of the circuit breaker mechanism 2, because if the circuit breaker mechanism 2 is in the open state, the pressed top plate 25 will abut against the top surface of the sliding frame 53, forcing the sliding frame 53 and the cable compartment door 3 to remain closed. In other words, when the first output shaft 14 rotates and moves the cam 40 away from the movable rod 42, if the circuit breaker mechanism 2 is in the open state, such that the top plate 25 is still pressed down and abuts against the sliding frame 53, the force of the return spring 421 is insufficient to drive the movable rod 42 upward, and the cable compartment door 3 remains in the fully locked state. Only when the first output shaft 14 rotates to move the cam 40 away from the movable rod 42, and the circuit breaker mechanism 2 is also in the closed state, causing the top plate 25 to move upward and clear the sliding frame 53, is the sliding frame 53 allowed to move upward under the action of the return spring 421 of the movable rod 42, and the cable compartment door 3 can move in the opening direction. In summary, the cable compartment door 3 can only be opened when the main contact of the three-position mechanism 1 is in the grounded position and the circuit breaker mechanism 2 is closed. If either of these two conditions is not met, the cable compartment door 3 is forcibly locked in the closed state and cannot be opened by force, eliminating the possibility of operators accidentally entering the energized compartment.

[0057] Furthermore, once the sliding frame 53 moves in the opening direction, it will block the tripping plate on the tripping drive shaft and restrict the circuit breaker mechanism 2 from tripping. Only when the cable compartment door 3 is closed in place will the sliding frame 53 move to allow the tripping plate on the tripping drive shaft to trip, thus allowing the circuit breaker mechanism 2 to trip.

[0058] Third interlocking module

[0059] The third interlocking module 6 is installed close to the circuit breaker mechanism 2, specifically, it can be installed on the second bracket 21 of the circuit breaker mechanism 2. The third interlocking module 6 includes a first interlocking baffle 61 and a second interlocking baffle 62, which establish an interlocking mechanism with the first interlocking module 4 through the second transmission component 200 and the third transmission component 300, respectively.

[0060] The first interlocking baffle 61 has a first hole 611 through which a pin can pass to mount the first interlocking baffle 61 to the first bracket 21, allowing the first interlocking baffle 61 to pivot about the pin. The first interlocking baffle 61 has a first arc-shaped groove 612, concentric with the first hole 611, at a position spaced apart from it. One end of a second transmission member 200, configured as a pull rod, is inserted into the first arc-shaped groove 612 and can move along it. The other end of the second transmission member 200 is connected to a crank arm 41 on the first output shaft 14 of the three-station cabinet 1. Rotation of the first output shaft 14 drives the first interlocking baffle 61 to rotate about the pin via the second transmission member 200.

[0061] When the main contact of the three-position mechanism 1 is in the isolated position, the rotation of the first output shaft 14 is transmitted to the first interlocking baffle 61 through the second transmission member 200, causing the first interlocking baffle 61 to pivot and lock the closing rod 22 on the closing drive shaft 23 of the circuit breaker mechanism 2, thereby restricting the closing of the circuit breaker mechanism 2. In the illustrated embodiment, the first interlocking baffle 61 has a bent protruding section, and by pivoting to block the rotation path of the closing rod 22, it locks the closing rod 22 of the circuit breaker mechanism 2, thereby restricting the closing of the circuit breaker mechanism 2. When the main contact of the three-position mechanism 1 is in the grounded position or the closed position, the rotation of the first output shaft 14 is transmitted to the first interlocking baffle 61 through the crank arm 41 and the second transmission member 200, causing the first interlocking baffle 61 to pivot and allow the closing rod 22 on the closing drive shaft 23 of the circuit breaker mechanism 2 to open, allowing the circuit breaker mechanism 2 to close.

[0062] The second interlocking baffle 62 has a second hole 621 through which a pin can pass to mount the second interlocking baffle 62 to the first bracket 21, allowing the second interlocking baffle 62 to pivot about the pin. In one embodiment, the first hole 611 of the first interlocking baffle 61 and the second hole 621 of the second interlocking baffle 62 are aligned and mounted to the first bracket 21 by means of the same pin. The second interlocking baffle 62 has a second arcuate groove 622 formed at a position spaced apart from the second hole 621, concentric with the second hole 621. A pin 63 fixed to the second bracket 21 passes through the second arcuate groove 622 and can move along the second arcuate groove 622. One end of the third transmission member 300, configured as a pull rod, is connected to the second interlocking baffle 62 at a position spaced apart from the second hole 621 and the second arcuate groove 622, and the other end is connected to the second opening of the first rotating member 452 or the second opening 466 of the second rotating member 462. In the illustrated embodiment, the other end of the third transmission member 300 is inserted into the second orifice 466 of the second rotating member 462.

[0063] When the circuit breaker mechanism 2 opens, as previously described, the top plate 25, pressed down by the rotation of the second output shaft 26 in the opening direction, pulls the interlock cover plate 44 to expose the closing operating shaft 12 and the grounding operating shaft 13, allowing operation of the operating shafts. Whether the second latch 461 is pushed by the closing handle 15 or the first latch 451 is pushed by the grounding handle 16, the presence of the connecting rod 49 synchronously drives the first rotating member 452 and the second rotating member 462, which in turn drives the second interlocking baffle 62 to move to lock the closing rod 22 on the closing drive shaft 23 of the circuit breaker mechanism 2, thereby restricting the closing of the circuit breaker mechanism 2. In the illustrated embodiment, the second interlocking baffle 62 has a bent protruding section, and by pivoting to block the rotation path of the closing rod 22, it locks the closing rod 22 of the circuit breaker mechanism 2, thereby restricting the closing of the circuit breaker mechanism 2.

[0064] The interlocking device of this utility model achieves the following interlocking mechanism:

[0065] 1. The cable compartment door must not be opened when the main contacts of the three-position switch are in the closed or isolated position;

[0066] 2. The cable compartment door must not be opened when the circuit breaker mechanism is tripping;

[0067] 3. When the circuit breaker mechanism is closed, the main contacts cannot be operated;

[0068] 4. The cable compartment door can only be opened when the main contacts of the three-position switch are in the grounded position and the circuit breaker mechanism is closed;

[0069] 5. The circuit breaker mechanism can only trip (including manual tripping and electric tripping) after the cable compartment door is completely closed.

[0070] 6. When operating the main contacts of the three-position switch, the circuit breaker mechanism cannot close;

[0071] 7. When the main contacts of the three-position switch are in the isolated position, the circuit breaker mechanism cannot close;

[0072] 8. When the main contacts of a three-position switch are in the isolated position, grounding or closing operations are permitted; when the main contacts of a three-position switch are in the grounded position, closing operations are not permitted; when the main contacts of a three-position switch are in the closed position, grounding operations are not permitted.

[0073] It should be understood that although this specification describes various embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0074] The above description is merely an illustrative embodiment of this utility model and is not intended to limit the scope of this utility model. Any equivalent changes, modifications, and combinations made by those skilled in the art without departing from the concept and principles of this utility model should fall within the protection scope of this utility model.

Claims

1. An interlocking device for a ring main unit, the ring main unit comprising: The cabinet includes a cable compartment, which is equipped with an openable and closable cable compartment door (3). The cabinet contains a three-position mechanism (1) and a three-position switch. The three-position switch has a main contact that can move between a closed position, an isolated position and a grounded position. The three-position mechanism (1) includes a first output shaft (14) connected to the main contact, and a closed operation shaft (12) and a grounding operation shaft (13) that drive the first output shaft (14). The circuit breaker mechanism (2) installed in the cabinet includes a second output shaft (26), and a closing mechanism and a opening mechanism that drive the connection of the second output shaft (26); The interlocking device is characterized in that it comprises: The first interlocking module (4) is installed in the cabinet near the three-station mechanism (1); The second interlocking module (5) is connected to the cable room door (3) and is connected to the first interlocking module (4) through the first transmission component (100). The third interlocking module (6) is installed in the cabinet near the circuit breaker mechanism (2) and is connected to the first interlocking module (4) through the second transmission component (200) and the third transmission component (300) respectively. When the cable compartment door (3) is closed, the second interlock module (5) drives the first interlock module (4) to move linearly away from the first output shaft (14) via the first transmission component (100), so as to allow the first output shaft (14) to rotate and drive the main contact to move toward the closed position or the isolated position; when the main contact moves to the closed position or the isolated position, the first interlock module (4) is restricted to move linearly in a direction close to the first output shaft (14) to keep the cable compartment door (3) closed; when the circuit is broken... When the circuit breaker mechanism (2) is open, the second interlocking module (5) is locked by the second output shaft (26) to keep the cable compartment door (3) closed; when the main contact moves to the ground position and the circuit breaker mechanism (2) is closed, the first interlocking module (4) is released to allow the cable compartment door (3) to open, while the second interlocking module (5) locks the opening mechanism; when the main contact is in the isolation position, the first interlocking module (4) drives the third interlocking module (6) to move to lock the closing mechanism through the second transmission component (200); The first interlocking module (4) is also connected to the second output shaft (26) via the fourth transmission member (400). When the circuit breaker mechanism (2) is opened, the second output shaft (26) drives the first interlocking module (4) to leave the closing operation shaft (12) and the grounding operation shaft (13) via the fourth transmission member (400). When the circuit breaker mechanism (2) is closed, the first interlocking module (4) automatically resets and locks the closing operation shaft (12) and the grounding operation shaft (13). When the closing operation shaft (12) and the grounding operation shaft (13) are allowed to operate, the first interlocking module (4) drives the third interlocking module (6) to move to lock the closing mechanism via the third transmission member (300).

2. The interlocking device for the ring main unit according to claim 1, characterized in that, The first interlocking module (4) includes: Cam (40) is engaged with the first output shaft (14); The movable rod (42) is capable of linear movement to move closer to or away from the first output shaft (14), and the movable rod (42) is rigidly connected to one end of the first transmission member (100); A return spring (421) is connected to the movable rod (42) and applies a force to the movable rod (42) to make it move linearly in a direction close to the first output shaft (14).

3. The interlocking device for the ring main unit according to claim 1 or 2, characterized in that, The second interlocking module (5) includes: The sliding frame (53) is rigidly connected to the other end of the first transmission member (100). The sliding frame (53) has a limiting groove (533) and an elongated groove (531) extending at an angle relative to its sliding direction. A stop cam (54) is pivotally mounted in the cabinet and has a rod (542) inserted into the long groove (531) of the sliding frame (53) and can move along the long groove (531); The hanging rod (51) is detachably connected to the cable compartment door (3) and is provided with a limiting rod (511) inserted into the limiting groove (533) of the sliding frame (53). The cable compartment door (3) moving in the closing direction drives the sliding frame (53) via the hanging rod (51). The sliding frame (53) drives the movable rod (42) to move linearly away from the first output shaft (14) via the first transmission member (100), so as to allow the first output shaft (14) to drive the main contact to move to the closing position or the isolation position. When the main contact moves to the closing position or the isolation position, the cam (40) presses against the movable rod (42) and restricts the movable rod (42) to move linearly in the direction close to the first output shaft (14), so as to keep the cable compartment door (3) in the closed state. When the first output shaft (14) drives the main contact to move to the grounding position, the cam (40) moves away from the movable rod (42).

4. The interlocking device for the ring main unit according to claim 3, characterized in that, The second output shaft (26) of the circuit breaker mechanism (2) is connected to a radially extending top plate (25). When the circuit breaker mechanism (2) is tripped, the second output shaft (26) rotates to press the top plate (25) against the sliding frame (53) to keep the cable compartment door (3) closed.

5. The interlocking device for the ring main unit according to claim 3, characterized in that, The tripping mechanism of the circuit breaker mechanism (2) includes a pivotable tripping drive shaft and a tripping plate engaged with the tripping drive shaft. When the cable compartment door (3) is closed in place, the sliding frame (53) releases the tripping plate to allow the circuit breaker mechanism (2) to trip. When the cable compartment door (3) moves in the opening direction, the sliding frame (53) locks the tripping plate to restrict the tripping of the circuit breaker mechanism (2).

6. The interlocking device for the ring main unit according to claim 3, characterized in that, A door-closing microswitch (43) is installed adjacent to the movable rod (42), which is triggered by the movable rod (42) moving away from the first output shaft (14) to provide a signal.

7. The interlocking device for the ring main unit according to claim 1, characterized in that, The first interlocking module (4) includes a crank arm (41) engaged with the first output shaft (14), and the third interlocking module (6) includes a pivotable first interlocking baffle (6) having a first arc groove (612). One end of the second transmission member (200) is connected to the crank arm (41), and the other end is inserted into the first arc groove (612) and can move along the first arc groove (612). When the main contact is in the isolation position, the crank arm (41) drives the first interlocking baffle (6) to pivot to lock the closing mechanism through the second transmission member (200) to restrict the closing of the circuit breaker mechanism (2).

8. The interlocking device for the ring main unit according to claim 1, characterized in that, The first interlocking module (4) includes: A first interlocking assembly (45) is disposed near the grounding operating shaft (13) and includes a first latch (451) and a first rotating member (452). During grounding operation of the grounding operating shaft (13) by the grounding handle (16), the first latch (451) is driven to drive the first rotating member (452) to pivot. The second interlocking assembly (46), located near the closing operation shaft (12), includes a second latch (461) and a second rotating member (462). During operation of the closing operation shaft (12) by the closing handle (15), the second latch (461) is driven to drive the second rotating member (462) to pivot. One of the first rotating member (452) and the second rotating member (462) is connected to one end of the third transmission member (300). A connecting rod (49) is connected between the first rotating member (452) and the second rotating member (462).

9. The interlocking device for the ring main unit according to claim 8, characterized in that, The first rotating member (452) and the second rotating member (462) each include: A shaft (463) is pivotally mounted inside the cabinet. An arm (464) extends radially from the shaft (463) and has a spaced-apart first opening (465) and second opening (466), one of which is for mounting the connecting rod (49) and the other is for mounting the third transmission member (300). A ridge (467) extends from the shaft (463) and gradually approaches the corresponding latch along the operating direction of the closing handle (15) or the grounding handle (16).

10. The interlocking device for the ring main unit according to claim 8, characterized in that, A grounding micro switch (48) is installed adjacent to the first handpiece (451). During the operation of the grounding operating shaft (13) by the grounding handle (16), the first handpiece (451) is driven, and the grounding micro switch (48) is triggered by the first handpiece (451) to provide a signal. A closing microswitch (47) is installed adjacent to the second handpiece (461). During the operation of the closing operation shaft (12) by the closing handle (15), the second handpiece (461) is driven, and the closing microswitch (47) is triggered by the second handpiece (461) to provide a signal.

11. The interlocking device for the ring main unit according to any one of claims 1 to 10, characterized in that, The third interlocking module (6) includes a pivotable second interlocking baffle (62) having a second arcuate groove (622) through which a pin fixed to the cabinet body passes. The pin can move along the second arcuate groove (622). The second interlocking baffle (62) is connected to the other end of the third transmission member (300). During the operation of the closing operation shaft (12) by the closing handle (15) or the operation of the grounding operation shaft (13) by the grounding handle (16), the first interlocking module (4) drives the second interlocking baffle (62) to pivot to lock the closing mechanism to restrict the closing of the circuit breaker mechanism (2).

12. The interlocking device for the ring main unit according to claim 1, characterized in that, The first interlocking module (4) includes a movable interlocking cover plate (44). The second output shaft (26) of the circuit breaker mechanism (2) is connected to a radially extending top plate (25). One end of the fourth transmission member (400) is connected to the top plate (25), and the other end is connected to the interlocking cover plate (44). During the opening of the circuit breaker mechanism (2), the top plate (25) drives the interlocking cover plate (44) away from the closing operation shaft (12) and the grounding operation shaft (13) through the fourth transmission member (400).

13. A ring main unit, comprising: The cabinet includes a cable compartment, which is equipped with an openable and closable cable compartment door (3). The cabinet contains a three-position mechanism (1) and a three-position switch. The three-position switch has a main contact that can move between a closed position, an isolated position and a grounded position. The three-position mechanism (1) includes a first output shaft (14) connected to the main contact, and a closed operation shaft (12) and a grounding operation shaft (13) connected to the first output shaft (14). The circuit breaker mechanism (2) installed in the cabinet includes a second output shaft (26), and a closing mechanism and a opening mechanism that drive the connection to the second output shaft (26); The ring main unit is characterized in that it further includes the interlocking device as described in any one of claims 1 to 12.

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