XGN cabinet mechanical interlocking device

Abstract

The utility model relates to a kind of XGN cabinet mechanical interlocking device, including, isolator, circuit breaker and interlocking rod, the box of isolator is equipped with travel switch and operating mechanism;The operating mechanism includes the operating rotating handle of installation on pin shaft, cam and the sector indicating board with text identification, the interlocking rod is movably arranged on isolator and circuit breaker, and is equipped with bent plate and movable lock pin, the movable lock pin is connected with the blade of circuit breaker;Travel switch is connected with closing coil, the normally closed contact of travel switch is located on the travel path of bent plate, the end of interlocking rod near bent plate is located on the movable path of cam.The utility model passes through electromechanical linkage mechanism, effectively overcome the defect that traditional single mechanical locking can be ineffective due to component wear or artificial short-circuit, constitutes multiple safety protection, significantly improves the intrinsic safety level of equipment operation, and compact structure, stable operation.

Description

Technical Field

[0001] This utility model relates to the field of fixed switchgear technology, and in particular to a mechanical interlocking device for an XGN cabinet. Background Technology

[0002] As a key power distribution device in the power system, the operational safety of the XGN series box-type fixed switchgear is of paramount importance. Among the "five protections" requirements for switchgear, "preventing the opening and closing of disconnecting switches under load" is the core requirement. If the disconnecting switch is mistakenly operated when the circuit breaker has not been reliably opened, a strong electric arc will be generated, leading to serious damage to the equipment and endangering the safety of the operators.

[0003] To meet this requirement, existing technologies generally employ mechanical interlocking devices. The typical principle is as follows: a mechanical structure, including linkages and shafts, forcibly links the circuit breaker's opening and closing states with the disconnector's operating mechanism. Only when the circuit breaker is in the open position will its interlocking mechanism release the constraint on the disconnector's operating handle, allowing opening and closing operations; conversely, when the circuit breaker is in the closed position, the mechanical interlock physically locks the operating handle, thus preventing accidental operation under load.

[0004] However, in practice, the following inherent defects and potential risks exist: First, traditional mechanical interlocks rely solely on the mechanical structure, with the entire interlocking function depending entirely on the strength and precision of the mechanical components. Under prolonged and frequent operation or improper maintenance, critical components such as connecting rods and pins may wear, deform, or even break, leading to interlocking failure and creating significant safety hazards. Furthermore, existing solutions cannot prevent personnel from forcibly connecting the circuit breaker's electrical closing circuit through other means. If the electrical closing circuit is accidentally connected, and the mechanical interlock happens to fail, it will directly lead to a catastrophic accident of closing the circuit breaker under load. Utility Model Content

[0005] In order to solve the technical problems mentioned in the background art, this utility model provides an XGN cabinet mechanical interlocking device with higher security and stronger reliability.

[0006] The technical solution is as follows: an XGN cabinet mechanical interlocking device, comprising a disconnecting switch, a circuit breaker and an interlocking rod, wherein the disconnecting switch housing is provided with a limit switch and an operating mechanism; The operating mechanism includes an operating rotary handle mounted on a pin shaft, a cam, and a fan-shaped indicator plate with text markings. The interlocking rod is movably mounted on the disconnecting switch and the circuit breaker, and is equipped with a bent plate and a movable locking pin. The movable locking pin is connected to the switch of the circuit breaker. The limit switch is connected to the closing coil, and the normally closed contact of the limit switch is located on the travel path of the bent plate. The end of the interlocking rod near the bent plate is located on the movement path of the cam. When the operating handle is turned to the disconnected interlock position, the interlocking rod drives the movable locking pin to restrict the closing of the knife switch. At the same time, the bent plate presses the normally closed contact of the limit switch, causing the limit switch to disconnect and thus cutting off the electrical closing circuit.

[0007] Preferably, the interlocking rod includes: a first interlocking rod, which is slidably mounted on one side of the housing of the disconnecting switch via the interlocking rod support; a bent plate is installed on the side wall of the first interlocking rod, and one end of the first interlocking rod abuts against the cam surface; The second interlocking rod is slidably mounted on the other side of the disconnector's housing via the interlocking rod support, and one end of it is connected to the end of the first interlocking rod away from the cam via the first hinge element; The third interlocking rod is hinged to the side wall of the circuit breaker housing via an interlocking rod support. One end of the rod is connected to the other end of the second interlocking rod via a second hinge element, and the other end is equipped with a movable locking pin.

[0008] Preferably, the first hinge element includes a main body with a jaw structure, the main body being mounted on the extension end of the disconnector's housing via a fixing pin; A third connecting pin is provided at the end of the first interlocking rod away from the cam, and the third connecting pin is movably embedded in the tiger's mouth; The end of the first hinge element opposite to the tiger's mouth is connected to the second interlocking rod through the first connecting pin.

[0009] Preferably, the second hinge element has a slotted hole, and the slotted hole is connected to the second interlocking rod by a second connecting pin.

[0010] Preferably, a torsion spring is fitted on the second interlocking rod, with one end of the torsion spring abutting against the side wall of the circuit breaker housing and the other end fixed to the second interlocking rod.

[0011] Compared with the prior art, the present invention has the following advantages: This invention fundamentally improves the reliability of preventing misoperation through a dual mechanical and electrical interlocking design. First, the interlocking rod and movable locking pin directly restrict the circuit breaker knife, forcibly restricting physical interlocking. Second, the cam-driven bent plate triggers the limit switch, automatically cutting off the closing circuit when the isolating switch is operated, forming redundant protection.

[0012] This utility model effectively overcomes the defects of traditional single mechanical interlocks that may fail due to component wear or human short circuits through electromechanical linkage mechanism, forming multiple safety protections, significantly improving the inherent safety level of equipment operation, and has a compact structure and stable operation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model.

[0014] Figure 2 This utility model Figure 1 Enlarged view of point A in the image.

[0015] Figure 3 For the present utility model Figure 1 The side view at point B in the image.

[0016] The meanings of the reference numerals in the figure are as follows: 1: Disconnecting switch, 2: Limit switch, 3: Operating mechanism, 31: Operating rotary handle, 32: Cam, 33: Sector indicator plate, 4: First interlocking rod, 41: Bent plate, 42: Third connecting pin, 5: First hinge element, 51: Fixed pin, 52: First connecting pin, 6: Second interlocking rod, 7: Third interlocking rod, 8: Movable locking pin, 9: Torsion spring, 10: Circuit breaker, 11: Second hinge element, 11a: Slotted hole, 12: Second connecting pin, 13, 14, 15: Supporting interlocking rod. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] The XGN series box-type fixed switchgear is mainly used in 3.6-40.5KV three-phase AC 50Hz systems for receiving and distributing electrical energy. This switchgear complies with national standard GB3906 and national standard IEC298, and has five-proof interlocking functions. This mechanical interlock is an improvement and optimization based on the original interlock.

[0019] The mechanical interlocking device provided by this unit mainly realizes the load-bearing opening and closing of the isolating switch in the five-prevention system: the isolating switch and grounding switch can only be operated when the isolating switch operating mechanism is in the open-lock position. When the circuit breaker is in the closed position, the small rotary handle on the operating mechanism cannot be moved to the open-lock position, and the isolating switch and grounding switch cannot be operated. Only when the circuit breaker is in the open position can the rotary handle be easily moved to the open-lock position to operate the opening and closing of the isolating switch incoming line. At the same time, in order to prevent the closing coil from burning out due to prolonged energization, a limit switch is also added. When the rotary handle on the turntable mechanism is in the open-lock position, the electrical closing circuit of the circuit breaker is disconnected, and the circuit breaker closing coil will not be energized or burn out.

[0020] This utility model provides a mechanical interlocking device for XGN cabinets, which aims to completely solve the safety hazard of traditional pure mechanical interlocking losing its interlocking function due to component failure or human intervention in the electrical circuit through a dual interlocking scheme that combines mechanical and electrical methods.

[0021] like Figures 1 to 3 As shown, this device synchronously and forcibly transmits the operating state of the disconnector switch 1 to the circuit breaker 10, and simultaneously realizes a linkage mechanism for mechanical and electrical locking.

[0022] Operating mechanism 3, serving as the command initiation point for the entire system, is installed on the housing of disconnector switch 1. Operating mechanism 3 consists of three parts: a rotary handle 31, a cam 32, and a fan-shaped indicator plate 33 with text markings. These three parts are connected by a pin. When the rotary handle 31 is rotated, the profile of the cam 32 directly drives the subsequent interlocking rod to move, and its position is clearly indicated by the fan-shaped indicator plate 33, providing the operator with intuitive status indication. The fan-shaped indicator plate 33 indicates three positions: maintenance, operation, and disconnection / locking, which can be switched by rotating the rotary handle 31. The interlocking rod is crucial for displacement transmission; it consists of multiple hinged rods forming a transmission chain.

[0023] In this embodiment, the interlocking mechanism includes a first interlocking rod 4, a second interlocking rod 6, and a third interlocking rod 7 connected in series. The first interlocking rod 4 is slidably mounted on one side of the housing via multiple support points 14, with its left end always abutting against the contour surface of the cam 32. This structure ensures a high-response linkage between the operating mechanism and the interlocking rods; once the handle is turned, the action is immediately transmitted. A bent plate 41 is fixedly installed on the side wall of the first interlocking rod 4. Notably, the limit switch 2 is fixedly mounted on the housing, its position precisely calibrated so that its normally closed contact is exactly on the movement path of the bent plate 41 on the first interlocking rod 4. The limit switch 2 is connected in series to the closing coil circuit of the circuit breaker. This means that the on / off state of the limit switch directly determines whether the circuit breaker can be closed electrically.

[0024] The right end of the first interlocking rod 4 is connected to the second interlocking rod 6 via the first hinge element 5. The first hinge element 5 is mounted on the extension end of the housing of the disconnecting switch 1 via a fixed pin 51. Its unique "tiger mouth" structure accommodates the third connecting pin 42 at the right end of the first interlocking rod 4, forming a movable connection.

[0025] The second interlocking rod 6 is vertically arranged and slidably mounted on the other side of the disconnector switch 1 housing via multiple support points 13. The second interlocking rod 6 is a telescopic rod that can be extended or shortened, with its length adjusted via a self-locking mechanism. The other end (i.e., the lower end) of the second interlocking rod 6 is connected to the third interlocking rod 7 via a second hinge element 11. The third interlocking rod 7 is horizontally arranged and hinged to the circuit breaker 10 housing via multiple support points 15. Furthermore, a slotted hole 11a on the second hinge element 11 engages with the second connecting pin 12 at the lower end of the second interlocking rod 6, similar in function to a thumb-and-screw structure, further providing movement allowance for the interlocking rod and ensuring smooth force transmission.

[0026] refer to Figure 3 In this embodiment, a movable locking pin 8 is provided on the third interlocking rod 7. One end of the movable locking pin 8 is coaxially connected to the hinge shaft of the second hinge element 11. When the second interlocking rod 6 moves up and down, the second hinge element 11 rotates along its hinge shaft through the cooperation of the second connecting pin 12 and the slotted hole 11a, synchronously driving the movable locking pin 8 to rotate. The other end of the movable locking pin 8 is connected to the closing knife mechanism of the circuit breaker, specifically through the locking pin and the knife handle. A linkage mechanism is established between the movable locking pin 8 and the knife handle, providing a structural basis for mechanical locking. In addition, it should be noted that a torsion spring 9 is fitted on the second interlocking rod 6. One end of the torsion spring 9 abuts against the side wall of the circuit breaker 10 housing, and the other end is fixed to the second interlocking rod 6. The torsion spring 9 provides a restoring force for the second interlocking rod 6.

[0027] Working principle and realization of the double-locking effect: When the operator rotates the operating handle 31 to the "disconnection lockout" position, the rotation of the cam 32 pushes the first interlocking rod 4 to move to the right. This movement is transmitted through the entire linkage system, ultimately driving the third interlocking rod 7 and the movable locking pin 8 to rotate clockwise by a certain angle, physically restricting and locking the circuit breaker's closing mechanism, thus achieving the first layer of forced mechanical locking. Even if someone attempts to force operation, they will be blocked by this physical locking pin.

[0028] Simultaneously, the rightward movement of the first interlocking lever 4 causes the bent plate 41 on it to move synchronously. The bent plate 41 then presses down on the contacts of the limit switch 2, forcing its normally closed contacts to open. Since this contact is connected in series in the closing circuit, its opening is equivalent to disconnecting the circuit breaker's "closing power supply" from the circuit, completely cutting off the electrical closing path, thus forming a second independent electrical interlock. This structure effectively prevents accidents that may be caused by human error in shorting the closing circuit.

[0029] In summary, this invention transforms a single operation into a synchronized mechanical and electrical interlocking action through the dual cooperation of an interlocking rod and a limit switch. The mechanical interlock provides direct and rigid protection against misoperation, while the electrical interlock offers a deeper level of safety protection based on circuit logic. The two are redundant and complementary, greatly improving the reliability of the equipment in preventing operation of the isolating switch under load, fundamentally solving the problem of accidents caused by operation under load.

[0030] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications, improvements, and substitutions without departing from the inventive concept, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A mechanical interlocking device for an XGN cabinet, characterized in that: Includes a disconnect switch (1), a circuit breaker (10) and an interlocking rod, wherein the housing of the disconnect switch (1) is provided with a limit switch (2) and an operating mechanism (3). The operating mechanism (3) includes an operating rotary handle (31), a cam (32), and a fan-shaped indicator plate (33) with text markings mounted on a pin shaft. The interlocking rod is movably mounted on the disconnecting switch (1) and the circuit breaker (10), and is provided with a bent plate (41) and a movable locking pin (8). The movable locking pin (8) is connected to the knife switch of the circuit breaker (10). The limit switch (2) is connected to the closing coil. The normally closed contact of the limit switch (2) is located on the travel path of the bent plate (41). The end of the interlocking rod near the bent plate (41) is located on the movement path of the cam (32). When the operating handle is turned to the disconnected locking position, the interlocking rod drives the movable locking pin (8) to restrict the closing of the switch. At the same time, the bent plate (41) presses the normally closed contact of the limit switch (2), causing the limit switch (2) to disconnect, thereby cutting off the electrical closing circuit.

2. The XGN cabinet mechanical interlocking device according to claim 1, characterized in that: The interlocking lever includes: The first interlocking rod (4) is slidably set on one side of the housing of the disconnecting switch (1) via the interlocking rod support (13, 14, 15); the bent plate (41) is installed on the side wall of the first interlocking rod (4), and one end of the first interlocking rod (4) abuts against the surface of the cam (32); The second interlocking rod (6) is slidably disposed on the other side of the housing of the disconnecting switch (1) via the interlocking rod support (13, 14, 15), and one end of it is connected to the end of the first interlocking rod (4) away from the cam (32) via the first hinge element (5). The third interlocking rod (7) is hinged to the side wall of the circuit breaker (10) box via interlocking rod supports (13, 14, 15). One end of the rod is connected to the other end of the second interlocking rod (6) via the second hinge element (11), and the other end is provided with a movable locking pin (8).

3. The XGN cabinet mechanical interlock device according to claim 1, characterized in that: The first hinge element (5) includes a body having a tiger's mouth structure, the body being mounted on the housing extension end of the disconnect switch (1) by a fixing pin (51); The first interlocking rod (4) is provided with a third connecting pin (42) at the end away from the cam (32), and the third connecting pin (42) is movably embedded in the tiger's mouth; The end of the first hinge element (5) opposite to the tiger's mouth is connected to the second interlocking rod (6) through the first connecting pin (52).

4. The XGN cabinet mechanical interlocking device according to claim 1, characterized in that: The second hinge element (11) has a slotted hole (11a) on it, and the slotted hole (11a) is connected to the second interlocking rod (6) through the second connecting pin (12).

5. The XGN cabinet mechanical interlock device according to claim 1, characterized in that: A torsion spring (9) is fitted on the second interlocking rod (6). One end of the torsion spring (9) abuts against the side wall of the circuit breaker (10) box, and the other end is fixed on the second interlocking rod (6).

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