Three-position mechanism under high-voltage cabinet door interlocking device

Abstract

The utility model discloses high -voltage cabinet three position mechanism lower cabinet door interlock device belongs to high -voltage switch equipment technical field, including cabinet frame, install in the three position assembly of cabinet frame and its screw rod in and set up in the interlocking mechanism of cabinet frame lower part, interlocking mechanism includes the cabinet door no.

Description

Technical Field

[0001] This utility model relates to the field of high voltage switchgear technology, and in particular to a lower cabinet door interlocking device for a three-position mechanism of a high voltage switchgear. Background Technology

[0002] High-voltage switchgear is a crucial power distribution device in power systems, typically integrating high-voltage components such as circuit breakers, disconnectors, and grounding switches. To simplify structure and operation, modern high-voltage switchgear generally adopts a "three-position mechanism," integrating the disconnector, circuit breaker, and grounding switch into one unit, enabling switching between closed, open, and grounded positions. Due to the involvement of high voltage, its operation and maintenance must adhere to strict safety procedures, among which the "five-proof" interlocking system is a measure to ensure the safety of personnel and equipment.

[0003] To achieve the "five-proof" function, especially to prevent operators from opening the cabinet door while it is energized or accidentally closing the switch after opening the door, existing high-voltage switchgear is equipped with interlocking devices. These devices rely heavily on electrical interlocking methods when making logical judgments. For example, by installing limit switches or position sensors on the cabinet door, the control circuit allows the operator to close the internal three-position mechanism only when the sensor detects that the cabinet door is completely closed and locked.

[0004] However, in practical applications, the aforementioned interlocking methods based on electrical signals have inherent safety risks. The reliability of electrical interlocking depends entirely on the normal operation of a series of electrical components, such as sensors, connecting cables, control relays, and the DC power supply for the interlocking circuit. If any of these components malfunctions, such as a sensor failing due to mechanical fatigue or dust contamination, contact sticking, or the control circuit breaking due to vibration, the interlocking system will output an incorrect permission signal.

[0005] Even if the cabinet door has been opened for maintenance, a malfunctioning interlocking system may still incorrectly allow the three-position mechanism to be closed. If anyone is working in front of the cabinet at this time, high-voltage electricity will be instantly introduced once the switch is closed, causing fatal electric shock to the maintenance personnel. Therefore, there is an urgent need for a solution that does not rely entirely on electrical signals and can provide a more direct and reliable mechanical forced interlocking mechanism to fundamentally prevent safety accidents caused by electrical faults in the interlocking system.

[0006] Therefore, this utility model proposes a lower cabinet door interlocking device for a three-position high-voltage switchgear mechanism to address the shortcomings of existing technologies. Utility Model Content

[0007] In view of the problems in the existing high-voltage switchgear three-position mechanism lower cabinet door interlocking device, such as excessive reliance on electrical interlocking, interlocking failure due to electrical component failure, and the possibility of accidental operation of internal switches even when the cabinet door is open, this utility model aims to provide a high-voltage switchgear three-position mechanism lower cabinet door interlocking device with improved structure that can effectively solve the above problems.

[0008] This utility model provides a cabinet door interlocking device for a three-position mechanism of a high-voltage switchgear, comprising: a cabinet frame; a three-position component installed inside the cabinet frame, the three-position component including a lead screw for driving it to change positions; and an interlocking mechanism disposed at the lower part of the cabinet frame.

[0009] The interlocking mechanism includes a cabinet door rotatably connected to the cabinet frame, and a positioning component for interlocking with the three-position assembly.

[0010] The positioning assembly includes a tapered block, a pressure plate, a connecting rod, a limit plate, a spring, and an electromagnetic lock, all coaxially connected to the lead screw.

[0011] Furthermore, these components are combined in the following manner: the pressure plate is slidably mounted on the cabinet frame, its position adjacent to the inner wall of cabinet door one, and is displaced by the inner wall of cabinet door one when cabinet door one is opened; one end of the pressure plate is connected to the limiting plate via a connecting rod; both ends of the spring are connected between the pressure plate and the fixed points on the cabinet frame, respectively, to provide a restoring force for the pressure plate; when the pressure plate is pushed, the limiting plate slides along the outer wall of the conical block under the drive of the connecting rod, and finally engages with the conical block, thereby forming a mechanical lock on the conical block, thus preventing the lead screw linked with the conical block from rotating; the electromagnetic lock is fixedly mounted on the cabinet frame, and is used to energize when the three-position assembly is in the closed state, its locking tongue extends to lock the pressure plate, preventing the pressure plate from displacing.

[0012] Preferably, the interlocking mechanism further includes a second cabinet door hinged to the cabinet frame and located behind the first cabinet door. The positioning component also includes a lever, which is swayably disposed next to the conical block. When the lead screw rotates and drives the conical block to move, the conical block will move the lever, thereby locking or unlocking the second cabinet door to enhance internal isolation.

[0013] Preferably, the interlocking mechanism further includes a locking assembly for locking cabinet door one. The locking assembly includes a bevel gear rotatably mounted on cabinet door one, and a pin meshing with the bevel gear. When the bevel gear rotates, it drives the pin to extend or retract axially, so that the end of the pin extends into or retracts from the lock hole on the cabinet frame, thereby locking or unlocking cabinet door one.

[0014] Preferably, the device further includes bolts that pass through the wall panel of the cabinet door and are fixed to the guide seat of the latch. This arrangement is used to reinforce the connection of the latch and provide stable guidance and limitation for its axial movement.

[0015] Preferably, the interlocking device for the lower cabinet door of the three-position high-voltage switchgear also includes a connecting mechanism, which is electrically connected to the three-position switchgear and is specifically used to realize the external power supply wiring and internal power distribution functions of the high-voltage switchgear.

[0016] Preferably, the connection mechanism includes a positioning frame fixedly installed inside the cabinet frame, multiple insulators being securely fixed to the positioning frame by bolts, and multiple terminal blocks being fixedly installed at the end of these insulators away from the positioning frame for safe termination of external cables.

[0017] Preferably, the connection mechanism further includes a lead plate and a contact plate. The lead plate is rotatably mounted on the positioning frame, while the contact plate is fixed on the positioning frame. The lead plate can physically contact or separate from the contact plate by its own rotation, thereby acting as a manual disconnect switch to realize the connection or disconnection of the circuit.

[0018] Preferably, the lead plate is rotatably connected to the positioning frame via a rotating shaft. The connecting mechanism also includes a positioning rod, one end of which is fixed coaxially with the rotating shaft. When the lead plate rotates, the other end of the positioning rod abuts against the limiting structure on the positioning frame. This design is used to precisely limit the end position of the lead plate rotation, ensuring its reliability in the on or off state.

[0019] This utility model has the following beneficial effects:

[0020] 1. This utility model, by setting up a positioning assembly consisting of a pressure plate, a connecting rod, a limiting plate, and a conical block, uses the opening action of the cabinet door to drive the limiting plate to mechanically lock the conical block, which is linked to the operating screw of the three-position mechanism. This solves the serious safety hazard problem in the prior art where the high-voltage cabinet door, when open, still poses a risk of accidental operation of the internal switch, causing it to be energized and closed. It achieves the technical effect of forcibly and reliably binding the cabinet door state with the switch operation state, eliminating the risk of live operation, and greatly improving operational safety.

[0021] 2. This utility model combines the above-mentioned purely mechanical locking structure with an electromagnetic lock. When the three-position mechanism is in a closed and energized state, the electromagnetic lock is energized and locks the cabinet door opening mechanism. This solves the problem that a single interlocking method cannot simultaneously achieve the dual protection of "preventing energized door opening" and "preventing the switch from closing after door opening" due to failure. It achieves a systematic safety effect of electromechanical dual redundant interlocking, making the interlocking device more logical and reliable, and can prevent accidental entry into energized intervals and accidental power supply in all aspects.

[0022] 3. This utility model, by adding an internal second cabinet door and a corresponding lever locking mechanism, and designing the external power supply as an independent connection mechanism including insulators, terminal blocks, and rotatable lead plates, solves the problems of some interlocking devices having a simple structure, only protecting the main cabinet door, and having inconvenient external wiring and insufficient emergency response capabilities. It achieves a comprehensive effect of multi-level, all-round isolation protection and safe and convenient power distribution, which not only improves the structural integrity and safety of the device, but also enhances the practicality and emergency backup capability of the entire high-voltage cabinet. Attached Figure Description

[0023] Figure 1 This is a perspective view of the lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear proposed in this utility model.

[0024] Figure 2 This is a structural exploded view of the lower cabinet door interlocking device of the three-station high-voltage switchgear mechanism proposed in this utility model;

[0025] Figure 3 This is a partial structural diagram of the lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear proposed in this utility model.

[0026] Figure 4 This is a partial structural diagram of the lower cabinet door interlocking device of the three-station high-voltage switchgear mechanism proposed in this utility model.

[0027] Legend:

[0028] 1. Cabinet frame; 2. Interlocking mechanism; 201. Cabinet door one; 202. Cabinet door two; 203. Bevel gear; 204. Bolt; 205. Pin; 206. Lead screw; 207. Positioning assembly; 2071. Paddle; 2072. Limiting plate; 2073. Conical block; 2074. Spring; 2075. Connecting rod; 2076. Pressure plate; 2077. Electromagnetic lock; 3. Connecting mechanism; 301. Positioning frame; 302. Insulator; 303. Terminal block; 304. Rotating shaft; 305. Contact plate; 306. Lead plate; 307. Positioning rod; 4. Three-station assembly. Detailed Implementation

[0029] 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.

[0030] Example:

[0031] Please refer to Figures 1 to 4This utility model provides a cabinet door interlocking device for a three-position mechanism of a high-voltage switchgear, which aims to solve the problem that in the prior art, the internal three-position switch of a high-voltage switchgear may be accidentally operated when the cabinet door is open, resulting in energized closing and posing a serious safety hazard.

[0032] like Figure 1 and Figure 2 As shown, the lower cabinet door interlocking device of the high-voltage switchgear three-position mechanism includes a cabinet frame 1, a three-position component 4 installed inside the cabinet frame 1, and an interlocking mechanism 2 located at the lower part of the cabinet frame 1. The three-position component 4 includes a lead screw 206 for driving it to change positions. The function of the interlocking mechanism 2 is to forcibly convert the physical open state of the cabinet door 201 into a mechanical locking state of the lead screw 206 of the three-position component 4, and to electrically lock the cabinet door 201 when the three-position component 4 is energized, thereby forming a complete electromechanical interlocking chain. Specifically, the interlocking mechanism 2 includes a cabinet door 201 rotatably connected to the cabinet frame 1, and a positioning component 207 for interlocking with the three-position component 4.

[0033] Reference Figure 2 and Figure 3 The positioning component 207 is key to realizing the function of this solution. It includes a conical block 2073, a pressure plate 2076, a connecting rod 2075, a limiting plate 2072, a spring 2074, and an electromagnetic lock 2077, all coaxially connected to the lead screw 206. The pressure plate 2076 is slidably mounted on the cabinet frame 1, and its position is adjacent to the inner wall of the cabinet door 201. When the cabinet door 201 is opened, its inner wall will push the pressure plate 2076 to move. One end of the pressure plate 2076 is connected to the limiting plate 2072 via the connecting rod 2075. When the pressure plate 2076 is pushed, the limiting plate... 2072 will slide along the outer wall of the conical block 2073 and eventually engage with the middle of the conical surface of the conical block 2073, forming a firm mechanical lock. Since the conical block 2073 is linked with the lead screw 206, the lead screw 206 is locked and cannot rotate, thus preventing any operation on the three-station assembly 4. The two ends of the spring 2074 are respectively connected to the pressure plate 2076 and the fixing point on the cabinet frame 1. When the cabinet door 201 is closed and the pressure plate 2076 is no longer pressed, it provides a rebound force to reset the pressure plate 2076, thereby driving the limit plate 2072 to disengage from the lock on the conical block 2073.

[0034] Electromagnetic lock 2077 is fixedly installed on cabinet frame 1, and its position is directly opposite pressure plate 2076. Electromagnetic lock 2077 is electrically connected to the main circuit status detection signal of three-position component 4. When three-position component 4 is in the closed energized state, electromagnetic lock 2077 is energized, and its locking tongue extends to lock or press pressure plate 2076, so that pressure plate 2076 cannot be displaced. Even if someone tries to open cabinet door 201 at this time, they cannot push pressure plate 2076, thus realizing the electrical locking of cabinet door.

[0035] To further enhance the comprehensiveness of the interlocking mechanism, the interlocking mechanism 2 also includes a second cabinet door 202, hinged to the cabinet frame 1 and located behind the first cabinet door 201. The second cabinet door 202 is used to isolate the operating area of ​​the three-station assembly 4; please refer to Figure 3 The positioning component 207 also includes a lever 2071, which is swayably disposed next to the conical block 2073. Its specific structure is an L-shaped lever that rotates around a fixed axis. When the operator needs to operate the three-position component 4 after closing the cabinet door 1 201, the rotating screw 206 will drive the conical block 2073 to move axially. The conical surface of the conical block 2073 will push one end of the lever 2071, causing it to swing around the axis, while the other end moves to the inner edge of the cabinet door 2 202, thereby locking the cabinet door 2 202. Conversely, when the three-position component 4 is operated and the conical block 2073 moves in the opposite direction, the lever 2071 swings back to its original position under its own weight or the action of the return spring 2074, releasing the lock on the cabinet door 2 202. This design ensures that the internal isolation door cannot be opened when the main switch is in the closing process or after the closing state.

[0036] To lock cabinet door 201 itself, please refer to... Figure 2 The interlocking mechanism 2 also includes a locking assembly, which includes a bevel gear 203 rotatably mounted on the cabinet door 201 and a pin 205 meshing with the bevel gear 203. The pin 205 can move axially within its guide seat. When the bevel gear 203 is rotated by an external key or handle, its teeth drive the rack on the pin 205 to move, causing the pin 205 to extend and insert into a preset lock hole on the cabinet frame 1, thereby locking the cabinet door 201. Reverse rotation retracts the pin 205 to unlock it. To ensure the connection strength and long-term reliability of the locking assembly, a bolt 204 is also included. The bolt 204 passes through the wall panel of the cabinet door 201 and is fixed to the guide seat of the pin 205, reinforcing the mounting structure of the pin 205 and serving as a limit for its movement.

[0037] In a preferred embodiment, to further enhance the security of internal isolation after cabinet door 201 is opened, the interlocking mechanism 2 also includes cabinet door 202, which is hinged to the cabinet frame 1 and located behind cabinet door 201. The positioning component 207 also includes a lever 2071, which is swayably positioned next to the conical block 2073. When the lead screw 206 rotates and drives the conical block 2073 to move, the lever 2071 is actuated by the side wall of the conical block 2073, thereby achieving mechanical locking or unlocking of cabinet door 202. In another preferred embodiment, to provide a structure that reliably locks cabinet door 201 itself, the interlocking mechanism 2 also includes a locking assembly. The fastening assembly includes a bevel gear 203 rotatably mounted on cabinet door 201, and a pin 205 meshing with the bevel gear 203. The pin 205 extends or retracts axially when the bevel gear 203 rotates, its end extending or retracting to engage with a pre-set lock hole on the cabinet frame 1 to lock or unlock. In a preferred embodiment, to reinforce the installation of the pin 205 and precisely define its movement trajectory, the device also includes a bolt 204. The bolt 204 passes through the wall panel of cabinet door 201 and is fixed to the guide seat of the pin 205, providing stable support and guidance for the reciprocating movement of the pin 205. In another preferred embodiment, to achieve a safe interlock... Simultaneously, integrating the functions of introducing and distributing external high-voltage cables, the device also includes a connection mechanism 3, which is electrically connected to the three-station assembly 4. In a preferred embodiment, to construct a safe and well-insulated wiring platform, the connection mechanism 3 includes a positioning frame 301 fixedly installed within the cabinet 1. Multiple insulators 302 are fixed to the positioning frame 301 by bolts 204, while multiple terminal blocks 303 are fixedly installed at the end of the insulators 302 away from the positioning frame 301 for connecting external cables. In another preferred embodiment, to provide a manual switching function for circuit on / off, the connection mechanism 3 also includes a lead plate 306 and a contact plate 305. The lead plate 306 is rotatably mounted on the positioning frame 301, and the contact plate 305 is fixed on the positioning frame 301. The lead plate 306 achieves contact or separation with the contact plate 305 through its own rotation. In a preferred embodiment, in order to ensure the accuracy and stability of the rotation switching of the lead plate 306, the lead plate 306 is rotatably connected to the positioning frame 301 through the rotating shaft 304. The connecting mechanism 3 also includes a positioning rod 307. One end of the positioning rod 307 is coaxially fixed with the rotating shaft 304, and the other end is used to abut against the limiting structure on the positioning frame 301 when the lead plate 306 rotates to a predetermined angle, thereby accurately defining its working position of being connected or disconnected.

[0038] Working principle: In the normal closed state, cabinet door 201 is locked to cabinet frame 1 by bolt 205. At this time, the three-position component 4 can be in any working position. If the three-position component 4 is in the closed and energized state, the electromagnetic lock 2077 will be energized and its bolt will extend to block the pressure plate 2076. At this time, even if the bolt 205 is unlocked, cabinet door 201 cannot be opened because the pressure plate 2076 cannot be moved, thus achieving reliable electrical interlocking.

[0039] When a power outage is required for maintenance, the operator must first operate the three-position assembly 4 to the open or grounded position. At this time, the electromagnetic lock 2077 is de-energized, its locking tongue retracts, and the locking of the pressure plate 2076 is released. The operator unlocks and opens the cabinet door 201. During the opening process, the inner wall of the cabinet door 201 will squeeze and push the pressure plate 2076. The pressure plate 2076 overcomes the tension of the spring 2074 and moves, and through the connecting rod 2075, it drives the limit plate 2072 to slide along the outer wall of the conical block 2073, and finally locks into the locked position of the conical block 2073. At this time, the lead screw 206 linked with the conical block 2073 is locked by pure mechanical force and cannot be rotated, eliminating the possibility of accidentally operating the three-position assembly 4 to close the circuit and supply power while the cabinet door is open.

[0040] After the maintenance work is completed, the operator must first close cabinet door 201. During the closing process, the thrust applied to the pressure plate 2076 disappears, and the rebound force of the spring 2074 will pull the pressure plate 2076 back to its original position. The pressure plate 2076 drives the limit plate 2072 to disengage from the conical block 2073 through the connecting rod 2075, releasing the mechanical lock on the lead screw 206. At this time, the operator can operate the lead screw 206 normally to close and energize the three-position component 4. During the closing and energizing process, the lead screw 206 drives the conical block 2073 to move axially, thereby actuating the lever 2071 to lock the internal cabinet door 202, preventing personnel from contacting the internal components when energizing. After the closing is completed, the electromagnetic lock 2077 is energized again, locking the pressure plate 2076, and the entire device returns to the initial safe locking state.

Claims

1. A lower cabinet door interlocking device for a three-position high-voltage switchgear mechanism, comprising: Cabinet frame (1); The three-station assembly (4) is installed inside the cabinet (1), and the three-station assembly (4) includes a lead screw (206) for driving it to perform station changes. And an interlocking mechanism (2) located at the lower part of the cabinet frame (1); Its features are, The interlocking mechanism (2) includes a cabinet door (201) rotatably connected to the cabinet frame (1) and a positioning component (207) for interlocking with the three-station component (4). The positioning component (207) includes a conical block (2073), a pressure plate (2076), a connecting rod (2075), a limiting plate (2072), a spring (2074), and an electromagnetic lock (2077) that are coaxially connected to the lead screw (206). The pressure plate (2076) is slidably mounted on the cabinet frame (1), its position is adjacent to the inner side wall of the cabinet door (201), and it is pushed and displaced when the cabinet door (201) is opened; One end of the pressure plate (2076) is connected to the limiting plate (2072) via the connecting rod (2075); The two ends of the spring (2074) are respectively connected to the pressure plate (2076) and the fixing point on the cabinet (1) to provide a restoring force; When the pressure plate (2076) is pushed, the limiting plate (2072) slides along the outer wall of the conical block (2073) and engages with it to form a mechanical lock on the conical block (2073), thereby preventing the lead screw (206) from rotating; The electromagnetic lock (2077) is fixedly installed on the cabinet frame (1) and is used to energize the three-position assembly (4) when it is in the closed state. Its locking tongue extends to lock the pressure plate (2076) and prevent it from being displaced.

2. The lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear according to claim 1, characterized in that, The interlocking mechanism (2) also includes a second cabinet door (202) hinged to the cabinet frame (1) and located behind the first cabinet door (201). The positioning component (207) also includes a lever (2071), which is swayably disposed next to the conical block (2073) and is moved by the lever (206) to lock or unlock the second cabinet door (202) when the lead screw (206) rotates and drives the conical block (2073) to move.

3. The lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear according to claim 1, characterized in that, The interlocking mechanism (2) further includes a locking assembly for locking the cabinet door (201); the locking assembly includes a bevel gear (203) rotatably mounted on the cabinet door (201) and a pin (205) meshing with the bevel gear (203), the pin (205) extending axially when the bevel gear (203) rotates, so as to engage with the lock hole on the cabinet frame (1).

4. The lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear according to claim 3, characterized in that, It also includes bolts (204) that pass through the wall panel of the cabinet door (201) and are fixed on the guide seat of the pin (205) for reinforcing and limiting the connection of the pin (205).

5. The lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear according to claim 1, characterized in that, The device also includes a connection mechanism (3), which is electrically connected to the three-station assembly (4) for external wiring and power distribution of the high-voltage cabinet.

6. The interlocking device for the lower cabinet door of the three-position mechanism of the high-voltage switchgear according to claim 5, characterized in that, The connecting mechanism (3) includes a positioning frame (301) fixedly installed in the cabinet (1), and a plurality of insulators (302) fixed to the positioning frame (301) by bolts (204), and a plurality of terminal blocks (303) fixedly installed at the end of the insulators (302) away from the positioning frame (301).

7. The lower cabinet door interlocking device of the three-position mechanism of the high-voltage switchgear according to claim 6, characterized in that, The connection mechanism (3) further includes a lead plate (306) and a contact plate (305). The lead plate (306) is rotatably mounted on the positioning frame (301), and the contact plate (305) is fixed on the positioning frame (301). The lead plate (306) rotates to contact or separate from the contact plate (305) to realize the connection or disconnection of the circuit.

8. The interlocking device for the lower cabinet door of the three-position mechanism of the high-voltage switchgear according to claim 7, characterized in that, The lead plate (306) is rotatably connected to the positioning frame (301) via a rotating shaft (304). The connecting mechanism (3) also includes a positioning rod (307). One end of the positioning rod (307) is coaxially fixed with the rotating shaft (304), and the other end is used to abut against the limiting structure on the positioning frame (301) when the lead plate (306) rotates, thereby limiting its rotation position.

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