Visual isolating switch of high-voltage vacuum circuit breaker

Abstract

The invention relates to the technical field of high-voltage vacuum circuit breakers, in particular to a visual isolating switch of a high-voltage vacuum circuit breaker, which comprises a first connecting base and a second connecting base, and is characterized in that the first connecting base is connected with a wire inlet conducting rod. By arranging the conducting rod, the moving frame and other action parts on one side of the circuit breaker main body through the mounting plate, a worker can directly observe the relative position of the conducting rod and the connecting base, and when the conducting rod is inserted into the connecting base, the conducting rod is in a closing state and when the conducting rod is separated from the connecting base, the conducting rod is in an opening state; the visual design solves the problem that the state of a traditional built-in disconnecting switch is hidden and difficult to judge, the misoperation risk is reduced fundamentally, the safety during overhaul and maintenance is guaranteed, the movement of the conducting rod is directly linked with the opening and closing actions of the disconnecting switch, the position change of the conducting rod is completely synchronous with the actual on-off state, and the safety of the disconnecting switch is ensured. The problem of hysteresis or asynchronization of a traditional external indicating device is avoided, and the accuracy of state information transmission is ensured.

Description

Technical Field

[0001] This invention relates to the field of high-voltage vacuum circuit breaker technology, and more particularly to a visual disconnect switch for a high-voltage vacuum circuit breaker. Background Technology

[0002] In the operation of power systems, high-voltage vacuum circuit breakers serve as critical control and protection devices, and their safe and stable operation directly affects the reliability of the power grid. When personnel conduct regular inspections and maintenance of high-voltage vacuum circuit breakers, disconnecting switches are crucial supporting equipment to ensure operational safety.

[0003] A type of outdoor vacuum circuit breaker with an integrated disconnector, disclosed in CN113471011A, includes a housing, a first bushing, a second bushing, a vacuum interrupter, and a disconnector. The first and second bushings are located on opposite sides of the housing, and an insulating box is fixed inside the housing. The disconnector and the vacuum interrupter are installed in different chambers on the insulating box. This outdoor vacuum circuit breaker has a relatively reasonable structural design, is relatively easy to assemble, and is conducive to improving production efficiency. Furthermore, the product exhibits good stability during use. However, existing high-voltage vacuum circuit breakers with integrated disconnectors still have some shortcomings. On the one hand, because the disconnector is built into the housing, it is difficult for workers to visually observe its actual status during inspection and maintenance, making it impossible to accurately determine whether it is truly in the open position. This increases the risk of misoperation and poses a safety hazard. On the other hand, existing external indicating devices often lag or are asynchronous with the actual operation of the disconnector, failing to transmit the disconnector's status information in real time and accurately, further reducing the safety and reliability of inspection and maintenance work. In addition, the structural design of some built-in disconnect switches makes condition detection and fault diagnosis difficult, requiring the disassembly of many components for inspection. This not only increases the workload of staff but also prolongs maintenance time and affects the normal operation of the power system.

[0004] Therefore, in order to solve the problems of poor visibility, inaccurate status indication and low safety of the built-in disconnecting switch of the existing high-voltage vacuum circuit breaker during the maintenance process, it is of great practical significance to develop a visual disconnecting switch of the high-voltage vacuum circuit breaker that can clearly and in real time display the status of the disconnecting switch. Summary of the Invention

[0005] The purpose of this invention is to solve the problem in existing disconnector technology that it is difficult to intuitively observe the actual state of the disconnector and to accurately determine whether it is truly in the open position. This invention provides a visual disconnector for high-voltage vacuum circuit breakers, which solves the problem of the hidden and difficult-to-determine state of traditional built-in disconnectors through a visual design.

[0006] To achieve the above objectives, the present invention provides a visual disconnecting switch for a high-voltage vacuum circuit breaker, comprising a first connecting base and a second connecting base. The first connecting base is connected to an incoming conductive rod, and the second connecting base is connected to an outgoing conductive rod. A conductive rod is provided above both the first and second connecting bases. The upper end of the conductive rod is connected to a movable frame, and the movable frame is connected to a pushing mechanism. The pushing mechanism is used to drive the conductive rod to move and is connected to a mounting plate located on one side of the circuit breaker body.

[0007] As a further description of the above technical solution: both the incoming conductor rod and the outgoing conductor rod are connected to the circuit breaker body, and the circuit breaker body is mounted on the base plate.

[0008] As a further description of the above technical solution: the movable frame includes a cross frame, both ends of which are connected to guide rods and the two guide rods are connected to each other, and the other two ends of the cross frame are connected to lifting plates, which are connected to a pushing mechanism.

[0009] As a further description of the above technical solution: the pushing mechanism includes a drive shaft, which is connected to one end of a drive arm, and the other end of the drive arm is connected to a push rod. Multiple pushing components are connected to the push rod, which is connected to a movable frame, and the push rod is connected to a mounting plate through a limiting cylinder.

[0010] As a further description of the above technical solution: the drive arm includes a drive crank arm, one end of which is connected to the drive shaft, and the other end of which is connected to the driven crank arm via a drive pin. The end of the driven crank arm away from the drive pin is connected to a push rod, and a first elongated sliding hole adapted to the drive pin is provided on the driven crank arm.

[0011] As a further description of the above technical solution: the pushing component includes a sleeve, the sleeve is fixed on the pushing rod, the two ends of the sleeve are connected to pushing plates, the ends of the pushing plates are connected to pushing pins, the two ends of the pushing pins pass through the moving frame, and the two ends of the pushing pins are fitted with rollers.

[0012] As a further description of the above technical solution: the limiting cylinder is connected to the mounting plate, a limiting sliding hole is opened on one side of the limiting cylinder, the sleeve is rotatably connected in the limiting sliding hole, and a limiting insertion hole adapted to the guide rod is opened inside the limiting cylinder.

[0013] As a further description of the above technical solution: both the first connecting base and the second connecting base are provided with insertion holes adapted to the guide rod. The insertion holes are provided with slots in the circumference, and the slots are provided with touch springs.

[0014] As a further description of the above technical solution: the touch spring is ring-shaped, and there are two touch springs.

[0015] As a further description of the above technical solution: the lifting plate has a second elongated sliding hole on its side.

[0016] The above technical solution has the following advantages or beneficial effects:

[0017] This invention sets the moving parts, such as the conductor rod and the moving frame, on one side of the circuit breaker body via a mounting plate. The relative position of the conductor rod and the connecting base can be directly observed. When the conductor rod is inserted into the connecting base, it is in the closed state; when it is detached, it is in the open state. This visualization design solves the problem of the concealed and difficult-to-judge status of traditional built-in disconnecting switches, fundamentally reducing the risk of misoperation and ensuring safety during maintenance. The movement of the conductor rod is directly linked to the opening and closing action of the disconnecting switch, and its position change is completely synchronized with the actual on / off state. This avoids the lag or asynchrony problem of traditional external indicating devices and ensures the accuracy of status information transmission. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a visual disconnect switch in one embodiment of the present invention;

[0019] Figure 2 This is a side view of a visual disconnect switch in one embodiment of the present invention;

[0020] Figure 3 for Figure 1 A schematic diagram of the central propulsion mechanism;

[0021] Figure 4 for Figure 3 Schematic diagram of the middle pusher component;

[0022] Figure 5 for Figure 1 A schematic diagram of the structure of the moving frame;

[0023] Figure 6 for Figure 1 Cross-sectional view of the middle conductor rod;

[0024] Figure 7 for Figure 6 A schematic diagram of the middle contact spring.

[0025] Legend:

[0026] 1. First connecting base; 2. Second connecting base; 3. Inlet conductive rod; 4. Outlet conductive rod; 5. Conductor rod; 6. Moving frame; 7. Pushing mechanism; 8. Mounting plate; 9. Circuit breaker body; 10. Base plate; 51. Plug hole; 52. Slot; 53. Contact finger spring; 61. Cross frame; 62. Lifting plate; 621. Second long waist sliding hole; 71. Drive shaft; 72. Drive arm; 73. Push rod; 74. Pushing component; 75. Limiting cylinder; 721. Drive crank arm; 722. Drive pin; 723. Driven crank arm; 724. First long waist sliding hole; 741. Sleeve; 742. Pushing plate; 743. Pushing pin; 744. Roller; 751. Limiting sliding hole; 752. Limiting plug hole. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the description of this invention, it should be noted that the terms "upper", "lower", "horizontal", 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 limitations on this invention.

[0029] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connect," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or 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.

[0030] Example 1:

[0031] like Figure 1-5As shown, the present invention provides a visual disconnecting switch for a high-voltage vacuum circuit breaker, comprising a first connecting base 1 and a second connecting base 2. The first connecting base 1 is connected to an incoming conductive rod 3, and the second connecting base 2 is connected to an outgoing conductive rod 4. A conductive rod 5 is provided above both the first connecting base 1 and the second connecting base 2. The upper end of the conductive rod 5 is connected to a moving frame 6, and the moving frame 6 is connected to a pushing mechanism 7. The pushing mechanism 7 is used to drive the conductive rod 5 to move. The pushing mechanism 7 is connected to a mounting plate 8, and the mounting plate 8 is located on one side of the circuit breaker body 9.

[0032] In the technical solution of this invention, by setting the moving parts such as the conductor rod 5 and the moving frame 6 on one side of the circuit breaker body 9 through the mounting plate 8, the operator can directly observe the relative position of the conductor rod 5 and the connecting base. When the conductor rod 5 is inserted into the connecting base, it is in the closed state, and when it is detached, it is in the open state. This visualization design solves the problem of the traditional built-in disconnector switch having a hidden status and being difficult to judge, thereby reducing the risk of misoperation from the root and ensuring safety during maintenance. The movement of the conductor rod 5 is directly linked to the opening and closing action of the disconnector switch, and its position change is completely synchronized with the actual on / off state, avoiding the lag or asynchrony problem of traditional external indicating devices and ensuring the accuracy of status information transmission.

[0033] Specifically, the conducting rod 5 is fixedly connected to the moving frame 6. The pushing mechanism 7 drives the two conducting rods 5 to move synchronously through the moving frame 6, achieving simultaneous insertion or disengagement with the two connecting bases. This ensures the consistency of circuit opening and closing and avoids faults caused by poor contact on one side. The pushing mechanism is fixed to one side of the circuit breaker body by the mounting plate, forming an independent and stable transmission system, reducing interference with other internal components of the circuit breaker. At the same time, the mounting plate provides rigid support for the pushing mechanism, ensuring stable force transmission during the driving process and preventing component shaking or offset from affecting the accuracy of action. Core components (such as conducting rods, moving frame, and pushing mechanism) are external or semi-external, allowing operators to directly observe the status of each component (such as whether it is worn or whether the connection is loose) without disassembling a large number of outer shells or internal components of the circuit breaker body, greatly reducing the labor intensity of maintenance.

[0034] The incoming conductor rod 3 and the outgoing conductor rod 4 are both connected to the circuit breaker body 9, and the circuit breaker body 9 is mounted on the base plate 10.

[0035] like Figure 3 and Figure 5As shown, the movable frame 6 includes a cross frame 61, with both ends of the cross frame 61 connected to the guide rods 5, and the two guide rods 5 connected to each other. The other two ends of the cross frame 61 are connected to lifting plates 62, which are connected to the pushing mechanism 7. The cross frame 61 is directly connected to the two guide rods 5 at both ends, and the two guide rods 5 are connected through the internal structure of the cross frame 61, ensuring that the two guide rods 5 always move synchronously. When the pushing mechanism 7 drives the movable frame 6 to move, the two guide rods 5 can be inserted into or disengaged from the connecting base at the same time, avoiding poor contact caused by unilateral lag or offset, and greatly improving the accuracy of the opening and closing action.

[0036] Specifically, the lifting plate 62 has a second elongated sliding hole 621 on its side. The lifting plate 62, which is connected to both ends of the cross frame 61 longitudinally, is a component that directly contacts the pushing mechanism 7. The second elongated sliding hole 621 on its side forms a flexible transmission structure. It allows for slight movement deviations between the pushing mechanism 7 and the moving frame 6. The error is compensated by relative sliding within the sliding hole, avoiding jamming caused by rigid collisions and ensuring smooth movement. The lifting plate 62 provides a stable working surface for the pushing component of the pushing mechanism. Compared with single-point drive, this surface contact transmission can disperse the driving force, reduce local stress concentration, and reduce the risk of component damage.

[0037] The cross-shaped frame 61 integrates the connection of the two conducting rods 5, the current conduction channel, and the connection interface with the push mechanism 7 into one unit, eliminating the need for additional connectors or transmission intermediaries. This simplifies the overall structure, reduces the number of components, and thus shrinks the installation space, making it more suitable for the compact layout on one side of the circuit breaker body.

[0038] The rigid connection between the cross frame 61 and the conductor rod 5 ensures that the lifting and lowering of the conductor rod 5 are completely synchronized. By observing the position of the cross frame or the conductor rod 5, the staff can accurately determine the opening and closing status of the disconnecting switch, further enhancing the reliability of the "visual" function.

[0039] like Figure 3 and Figure 4 As shown, the pushing mechanism 7 includes a drive shaft 71, which is connected to one end of a drive arm 72. The other end of the drive arm 72 is connected to a push rod 73. Multiple push components 74 are connected to the push rod 73. The push rod 73 is connected to the moving frame 6 and is connected to the mounting plate 8 through a limit cylinder 75. By strictly matching the movement of the push rod 73 and the moving frame 6, the opening and closing states of the conductor rod 5 are synchronized with the movement of the drive shaft 71 without any lag, solving the problem of "asynchrony" in traditional indicating devices. All transmission components are exposed and move stably. Operators can intuitively judge the status of the disconnecting switch by observing the position of the push rod 73 and the moving frame 6 without relying on indirect indication, providing a core guarantee for the safe visibility and stable operation of the visual disconnecting switch.

[0040] like Figure 3 and Figure 4 As shown, the drive arm 72 includes a drive crank arm 721. One end of the drive crank arm 721 is connected to the drive shaft 71, and the other end of the drive crank arm 721 is connected to the driven crank arm 723 via a drive pin 722. The end of the driven crank arm 723 away from the drive pin 722 is connected to the push rod 73. A first elongated sliding hole 724 adapted to the drive pin 722 is provided on the driven crank arm 723. The drive crank arm 721 is connected to the driven crank arm 723 via the drive pin 722, and the first elongated sliding hole 724 on the driven crank arm 723 is... The long-waisted slide 724 allows the drive pin 722 to slide slightly within the hole, which can compensate for the deviation between the rotation trajectory (circular motion) of the drive 71 and the motion trajectory (linear motion) of the push rod 73, avoid "jamming" or "stress concentration" caused by rigid connection, and ensure smooth power transmission. The crank arm structure amplifies the driving torque through the lever principle. Under the same drive shaft output force, it can drive the push rod 73 to move more easily, reduce the action lag caused by excessive load, and improve the opening and closing response speed.

[0041] like Figure 3 and Figure 4 As shown, the pusher 74 includes a sleeve 741, which is fixed on the push rod 73. Push plates 742 are connected to both ends of the sleeve 741, and push pins 743 are connected to the ends of the push plates 742. The push pins 743 pass through the moving frame 6 at both ends, and rollers 744 are sleeved on both ends of the push pins 743. The rollers 744 sleeved on both ends of the push pins 743 directly contact the moving frame 6, transforming the traditional "sliding friction" into "rolling friction", which greatly reduces the wear rate of the contact parts and reduces the maintenance frequency. Multiple pushers 74 are distributed at intervals along the push rod 73, and the push pins 743 pass through the lifting plate 62 of the moving frame 6, which can ensure that the moving frame 6 is balanced when it is pushed, avoid the displacement of the guide rod 5 due to unilateral force, and ensure that it is accurately inserted into the insertion hole 51 of the connecting base. The sleeve 741 is fixed on the push rod 73, and the push plates 742 and push pins 743 form an integrated transmission chain. The power transmission path from the push rod to the moving frame is short and the loss is small, reducing the action lag.

[0042] like Figure 3 and Figure 4As shown, the limiting cylinder 75 is connected to the mounting plate 8. A limiting sliding hole 751 is provided on one side of the limiting cylinder 75, and the sleeve 741 is rotatably connected within the limiting sliding hole 751. A limiting insertion hole 752, adapted to the guide rod 5, is provided inside the limiting cylinder 75. The limiting sliding hole 751 on the side of the limiting cylinder 75 restricts the movement direction of the sleeve 741, ensuring that the push rod 73 always moves along a preset trajectory, avoiding lateral displacement due to vibration or assembly errors. The internal limiting insertion hole 752 and the guide rod... 5. The adapter assists in limiting the movement trajectory of the guide rod 5, ensuring precise alignment with the insertion hole 51 of the connecting base. The limiting sleeve 75 is fixed on the mounting plate 8, providing additional support for the push rod 73 and the guide rod 5, reducing the swaying of the long rod component during movement, and improving the stability of the overall structure. The sleeve 741 and the limiting sliding hole 751 are "rotatably connected", allowing the push rod 73 to make small angle adjustments during linear movement, avoiding jamming caused by rigid constraints, and further ensuring smooth operation.

[0043] Example 2:

[0044] like Figure 6 and Figure 7 As shown, both the first connecting base 1 and the second connecting base 2 have insertion holes 51 that are adapted to the conductor rod 5. The insertion holes 51 have circumferential slots 52, and the slots 52 are equipped with contact springs 53. By strictly matching the size of the insertion holes 51 with the conductor rod 5, when the disconnecting switch is closed, the conductor rod 5 can be accurately inserted into the base along the axial direction of the insertion holes 51, avoiding poor contact caused by misalignment. The circumferential slots 52 provide installation space for the contact springs 53, and at the same time reserve a buffer gap for spring deformation to prevent the spring from being rigidly squeezed and failing. The circumferential distribution design of the slots 52 allows the contact springs 53 to form a wrapping contact with the conductor rod 5 from multiple angles. Even if there is a slight radial wobble of the conductor rod 5 during insertion, the deviation can still be compensated by the elastic deformation of the spring to ensure the continuity of contact.

[0045] like Figure 6 and Figure 7As shown, the contact spring 53 is annular, and two contact springs 53 are provided. The annular contact spring 53 has good elasticity. When the conductive rod 5 is inserted into the insertion hole 51, the spring is radially compressed and applies a uniform clamping force to the conductive rod 5, so that the conductive rod is tightly attached to the inner wall of the base, effectively reducing the contact resistance. The annular structure makes the spring and the conductive rod 5 form a circumferential contact area, which is equivalent to multiple parallel conductive contacts. Even if local contact failure occurs due to oxidation or wear, the remaining part can still maintain the conductive path, improving the redundancy of the circuit connection. The two annular contact springs 53 are arranged axially spaced along the insertion hole 51, which can provide superimposed elastic clamping force. During long-term use, a single spring may experience fatigue and weaken its elasticity. However, the dual-spring design can maintain sufficient clamping force through the compensation of the other spring, extending the service life of the component. The spaced arrangement of the dual springs makes the force on the conductor rod 5 more even, avoiding local wear or deformation caused by concentrated force on a single spring, thus protecting the integrity of the conductive components. In outdoor high and low temperature environments, the conductor rod 5 and the base may undergo dimensional changes due to thermal expansion and contraction. The elasticity of the ring contact finger spring can adapt to this slight deformation, maintaining stable contact pressure and preventing contact loosening due to temperature changes. Outdoor circuit breakers may be affected by wind and equipment vibration during operation. The dual clamping action of the dual springs can effectively resist the loosening tendency caused by vibration, ensuring the stability of the conductive connection in the opening and closing states.

[0046] Specifically, the combination of plug-in hole guidance, slotted housing, and double-ring contact finger spring clamping fundamentally solves the problems of poor contact, severe overheating, and susceptibility to environmental influences in traditional disconnect switches. At the same time, it works in conjunction with the visibility design of the disconnect switch. When the staff confirms through external observation that the conductor rod 5 is inserted into the base, the reliable contact of the contact finger spring ensures that the circuit is truly connected, avoiding the safety hazard of visually closing the circuit but not actually connecting it. Ultimately, this improves the operational safety and reliability of high-voltage vacuum circuit breakers in power systems.

[0047] It should be noted that, in this document, the term "comprising" or any other variation thereof is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0048] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A visual disconnect switch for a high-voltage vacuum circuit breaker, characterized in that, It includes a first connecting base (1) and a second connecting base (2). The first connecting base (1) is connected to the incoming conductor rod (3), and the second connecting base (2) is connected to the outgoing conductor rod (4). A conductor rod (5) is provided above both the first connecting base (1) and the second connecting base (2). The upper end of the conductor rod (5) is connected to a moving frame (6). The moving frame (6) is connected to a pushing mechanism (7). The pushing mechanism (7) is used to drive the conductor rod (5) to move. The pushing mechanism (7) is connected to a mounting plate (8). The mounting plate (8) is located on one side of the circuit breaker body (9).

2. The visual disconnect switch according to claim 1, characterized in that, The incoming conductor rod (3) and the outgoing conductor rod (4) are both connected to the circuit breaker body (9), which is mounted on the base plate (10).

3. The visual disconnect switch according to claim 1, characterized in that, The movable frame (6) includes a cross frame (61), with both ends of the cross frame (61) connected to the guide rods (5), and the two guide rods (5) are connected to each other. The other two ends of the cross frame (61) are connected to lifting plates (62), and the lifting plates (62) are connected to the pushing mechanism (7).

4. The visual disconnect switch according to claim 1, characterized in that, The pushing mechanism (7) includes a drive shaft (71), which is connected to one end of a drive arm (72). The other end of the drive arm (72) is connected to a push rod (73). Multiple push components (74) are connected to the push rod (73). The push rod (73) is connected to a moving frame (6). The push rod (73) is connected to a mounting plate (8) through a limiting cylinder (75).

5. The visual disconnect switch according to claim 4, characterized in that, The drive arm (72) includes a drive crank arm (721), one end of which is connected to the drive shaft (71), and the other end of which is connected to the driven crank arm (723) via a drive pin (722). The end of the driven crank arm (723) away from the drive pin (722) is connected to the push rod (73). The driven crank arm (723) is provided with a first elongated sliding hole (724) that is adapted to the drive pin (722).

6. The visual disconnect switch according to claim 4, characterized in that, The pusher (74) includes a sleeve (741) fixed on the push rod (73). The sleeve (741) is connected to push plates (742) at both ends. The push plates (742) are connected to push pins (743) at their ends. The push pins (743) pass through the moving frame (6) at both ends. The push pins (743) are fitted with rollers (744) at both ends.

7. The visual disconnect switch according to claim 6, characterized in that, The limiting cylinder (75) is connected to the mounting plate (8). A limiting sliding hole (751) is provided on one side of the limiting cylinder (75). The sleeve (741) is rotatably connected in the limiting sliding hole (751). A limiting insertion hole (752) adapted to the guide rod (5) is provided inside the limiting cylinder (75).

8. The visual disconnect switch according to claim 1, characterized in that, The first connecting base (1) and the second connecting base (2) are both provided with insertion holes (51) that are compatible with the guide rod (5). The insertion holes (51) are provided with slots (52) in the circumferential direction. The slots (52) are provided with finger springs (53).

9. The visual disconnect switch according to claim 8, characterized in that, The finger spring (53) is annular, and there are two finger springs (53).

10. The visual disconnect switch according to claim 3, characterized in that, The lifting plate (62) has a second elongated sliding hole (621) on its side.

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