A kind of middle switch cabinet, transfer car and handcart transfer method

Abstract

The application discloses a middle-placed switch cabinet, a transfer trolley and a handcart transfer method, a guide hole and a first nut are arranged on a partition plate in a cabinet body, a guide sleeve, a limiting column, an L-shaped support plate, a sliding block and a spring are arranged below the partition plate, and the sliding block is in contact with a slope surface of a guide shaft; the transfer trolley comprises a guide shaft, a front nut and a rear nut, a transfer trolley rocker, a worm box and a rack, the rocker can be threadedly connected with the first nut, a worm section of the rocker is engaged with a worm wheel to drive the rack to ascend and descend, and the rocker and the spring are further matched to push the limiting column to ascend and descend. The application can realize interlocking and firm connection between the middle-placed switch cabinet and the transfer trolley and safe transfer of the handcart, and prevent the occurrence of unhooking or overturning accidents.

Description

Technical Field

[0001] This invention specifically relates to a centrally located switchgear, a transfer vehicle, and a method for transferring a handcart, belonging to the technical field of high-voltage power distribution equipment. Background Technology

[0002] The full name of a center-mounted switchgear is armored center-mounted withdrawable metal-enclosed switchgear. It belongs to the category of three-phase AC indoor complete high-voltage power distribution equipment, with an operating voltage typically between 10-35kV. It is used to receive and distribute electrical energy, and to control, protect, monitor, and measure power circuits. Because the circuit breaker is located in the middle layer of the cabinet, it is also simply called a center-mounted cabinet. The circuit breaker is usually placed on a chassis trolley, and the circuit breaker and the chassis trolley together form a circuit breaker trolley, also simply called a trolley.

[0003] As an important accessory for medium-voltage switchgear, the transfer cart's main function is to safely move the circuit breaker trolley from inside the switchgear and transport it to other locations during installation, commissioning, operation, and maintenance. Conversely, after installation, commissioning, or maintenance, the circuit breaker trolley must be moved back into the switchgear. Common circuit breakers, such as vacuum circuit breakers or sulfur hexafluoride circuit breakers, weigh approximately 200 kg and are eccentrically positioned with their studded contacts. Adding the chassis weight of about 40 kg, the overall weight of the trolley is considerable, resulting in a tall and slender shape. Existing transfer carts have a simple structure, connecting to the switchgear only via a simple hand-operated hook. This connection is unreliable and prone to accidental disengagement. Once the hook breaks, the transfer cart loses its connection to the switchgear, causing the cart to shift and creating a large gap between them. The circuit breaker, due to its eccentric weight, may fall, causing an accidental tipping over. This can result in equipment damage or, in severe cases, personnel injury. In practice, especially during the process of pulling the trolley out of the switch cabinet, there have been many accidents caused by the trolley becoming detached from the switch cabinet. Summary of the Invention

[0004] To address the problems of existing technologies, this invention proposes an interlocking method for transporting a centrally located switchgear, a transfer trolley, and a handcart, aiming to achieve a secure interlocking connection between the centrally located switchgear and the transfer trolley, as well as safe transport of the handcart, preventing accidents such as unhooking or overturning.

[0005] The technical solution of the present invention is as follows:

[0006] A centrally located switchgear includes a central partition plate horizontally fixed in the middle of the cabinet. First guide rails are provided on both sides of the central partition plate, and a handcart is placed on the first guide rails. The handcart includes a chassis and a circuit breaker, and a handcart rocker arm is provided on the chassis. The central partition plate is characterized by: a first bend formed by vertically bending the outer side downwards; guide holes are symmetrically arranged on both sides of the first bend; a first through hole is provided at the center of the first bend; a first nut is fixedly installed on the inner side of the first bend, and the first nut is coaxial with the first through hole; a second through hole is provided on the plane of the central partition plate near the first bend, and a second through hole is fixed below the central partition plate. A guide sleeve is provided, which is coaxial with the second through hole. A limit post is movably placed inside the guide sleeve, and the lower surface of the limit post is a first inclined surface. An L-shaped support plate is fixedly provided below the middle partition plate near the first bend. An upwardly protruding slide rail is provided at the center of the bottom surface of the L-shaped support plate. A slider is provided on the slide rail. One side of the slider abuts against the first nut, and the other side of the slider is connected to the vertical surface of the L-shaped support plate through a spring. A second inclined surface and a third inclined surface are provided on the slider. The side of the second inclined surface near the first nut is lower than the side near the spring. The second inclined surface of the slider is in parallel contact with the first inclined surface of the limit post.

[0007] Furthermore, a transfer trolley is provided in conjunction with the cabinet. The transfer trolley includes a horizontally arranged support plate, with second guide rails fixedly installed on both sides of the support plate. The front and rear sides of the support plate are both vertically bent downwards to form a front bend and a rear bend. Guide shafts are symmetrically arranged on both sides of the front bend, and the guide shafts are correspondingly arranged with the guide holes. A front nut and a rear nut are fixedly installed on the inner side of the middle of the front bend and the rear bend, respectively. A transfer trolley rocker arm passes through the middle of the front bend and the rear bend. Threaded sections, namely a front threaded section and a rear threaded section, are provided at both the front and rear ends of the transfer trolley rocker arm. The front threaded section and the rear threaded section of the transfer trolley rocker arm are respectively threadedly connected to the front nut and the rear nut. When the guide shaft and the guide hole are axially aligned, the front nut and the first nut are also axially aligned, and the front nut and the first nut have the same specifications and model.

[0008] Furthermore, a turbine box is fixedly installed below the support plate of the transfer vehicle, near the front bend. A worm gear is installed inside the turbine box, and a rotating shaft is fixedly installed at the center of the worm gear. A gear is coaxially fixedly connected to the rotating shaft. A worm segment is installed in the middle of the rocker arm of the transfer vehicle, near the front bend. The rocker arm passes through the turbine box, and the worm segment meshes with the worm gear. A rack seat is also vertically fixed below the support plate. A rack is slidably installed on the rack seat. The rack meshes with the gear, and the rack can pass through or out of the support plate.

[0009] Furthermore, limit pins are provided at both ends of the rear threaded section of the transfer vehicle rocker arm, and the limit pins pass through the body of the transfer vehicle rocker arm.

[0010] Furthermore, a rocker arm is provided at the end of the transfer vehicle rocker arm, and the rocker arm rocker arm has the same rocker arm rocker arm shape as the transfer vehicle rocker arm, and the two can share a single crank handle.

[0011] A method for transporting a handcart, when it is necessary to remove the handcart from the central switch cabinet, includes the following steps:

[0012] First, attach the crank handle to the handcart crank, turn the crank handle to move the circuit breaker to the maintenance position, and then remove the crank handle;

[0013] The second step is to open the circuit breaker compartment door of the central switchgear, move the transfer cart to the front of the switchgear, adjust the height of the transfer cart support plate so that the two guide shafts of the transfer cart are horizontally inserted into the guide holes of the partition plate in the cabinet, and make the front bend of the transfer cart abut against the first bend of the cabinet. At this time, the second guide rail of the transfer cart is connected with the first guide rail of the cabinet.

[0014] Third, attach the crank handle to the transfer cart crank arm, rotate the transfer cart crank arm to make it advance through the first through hole in the cabinet partition and be threaded and fixedly connected with the first nut; continue to rotate the crank handle so that the head of the transfer cart crank arm passes through the first nut and squeezes the slider to move backward along the slide rail. The spring is compressed, and at the same time, the limiting post that cooperates with the second inclined surface of the slider descends, and the limiting post no longer blocks the handcart from being pulled out; while the transfer cart crank arm is rotating, the worm gear section drives the worm wheel to rotate, the worm wheel drives the rotating shaft and gear to rotate, the gear drives the rack to descend, and the rack no longer blocks the handcart from entering the transfer cart;

[0015] Fourth, pull the handcart so that it moves along the first guide rail of the cabinet onto the second guide rail of the transfer cart. Once the handcart is completely transferred onto the transfer cart, rotate the crank handle in the opposite direction to make the transfer cart lever rotate backward. When the transfer cart lever disengages from the first nut, the spring pushes the slider to move, and the slider pushes the limit post to rise and protrude onto the surface of the cabinet's partition plate. At the same time as the transfer cart lever rotates in the opposite direction, the worm gear section drives the worm wheel to rotate, and the worm wheel drives the shaft and gear to rotate. The gear drives the rack to rise, and the rack protrudes onto the upper surface of the transfer cart support plate, thus preventing the handcart from moving backward. Finally, push the transfer cart to move the entire handcart away from the front of the switch cabinet.

[0016] Beneficial Effects: This invention, by incorporating components such as a first nut, slider, spring, and limit post on the partition plate of the centrally located switchgear, and a transfer trolley rocker arm on the transfer trolley (which is threaded to the first nut), reliably locks and securely connects the transfer trolley and the switchgear, preventing accidental disengagement. Simultaneously, the inclined surface between the limit post and the slider drives the rise and fall of the limit post, indicating whether the transfer trolley rocker arm is locked in place. Furthermore, a worm gear structure is located in the middle of the transfer trolley rocker arm, using a worm gear and rack and pinion mechanism to drive the rise and fall of the rack. When the transfer trolley is not carrying a handcart, if the rack protrudes to the upper surface of the transfer trolley support plate, it indicates that a reliable connection has not been formed between the transfer trolley and the switchgear, and the handcart is not ready for loading. When a handcart is loaded onto the transfer trolley, the protrusion of the rack also serves to prevent the handcart from moving backward. Therefore, this invention achieves a secure interlocking connection between the centrally located switchgear and the transfer trolley, facilitating the safe transport of the handcart and preventing accidents such as disengagement or tipping over. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of a centrally located switchgear.

[0018] Figure 2 for Figure 1 A schematic diagram of a switch cabinet with the circuit breaker compartment door concealed.

[0019] Figure 3 for Figure 2 Enlarged view of area A in the middle.

[0020] Figure 4 This is a schematic diagram showing the coordination between the transfer vehicle and the switchgear.

[0021] Figure 5 This is a schematic diagram of the partition in the switch cabinet.

[0022] Figure 6 for Figure 5 Front view.

[0023] Figure 7 for Figure 6 BB section view.

[0024] Figure 8 for Figure 7 Enlarged view of area C.

[0025] Figure 9 This is a schematic diagram showing the interaction between the slider and the limiting post.

[0026] Figure 10 This is a three-dimensional structural diagram of the turnover vehicle.

[0027] Figure 11 for Figure 10 The left view.

[0028] Figure 12 for Figure 11 DD section view.

[0029] Figure 13 for Figure 11 EE section view.

[0030] Figure 14 This is a schematic diagram showing the interaction of the rocker arm, turbine housing, gears, and rack of the transport vehicle.

[0031] The diagram shows the following components: 1 cabinet, 11 busbar and instrument room, 12 circuit breaker room, 13 cable room, 14 partition plate, 15 first guide rail, 16 chassis, 17 circuit breaker; 140 guide sleeve, 141 first bend, 142 guide hole, 143 first through hole, 144 second through hole, 145 limit post, 146 L-shaped bracket plate, 147 slider, 148 spring, 149 first nut, 161 handcart rocker arm, 162 handle, 1451 first inclined plane, 1461 slide rail, 1471 second inclined plane, 1472 third inclined plane, 1473 slide groove.

[0032] 2. Transfer cart, 21. Base frame, 22. Casters, 23. Lead screw, 24. Handwheel, 25. Support plate, 26. Transfer cart rocker arm, 27. Second guide rail, 28. Turbine box, 251. Rear bend, 252. Front bend, 253. Guide shaft, 254. Limit block, 261. Worm section, 262. Front threaded section, 263. Rear threaded section, 264. Shake, 265. Limit pin, 271. Limit hole, 281. Worm gear, 282. Rotating shaft, 283. Gear, 284. Rack, 285. Rack seat, 2511. Rear nut, 2521. Front nut. Detailed Implementation

[0033] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. All directional indications (such as up, down, left, right, front, back, etc.) are used only to explain the relative positional relationships and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly. It should also be noted that when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or may have an intervening element present. When an element is referred to as "connected to" another element, it can be directly connected to the other element or may have an intervening element present. Furthermore, descriptions involving "first," "second," etc., in this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0034] like Figures 1-4As shown, a centrally located switchgear has a main structure consisting of three layers: an upper layer containing busbars and an instrument compartment (isolated from each other) 11, a middle layer containing a circuit breaker compartment 12, and a lower layer containing a cable compartment 13. A central partition 14 is horizontally fixed in the middle of the cabinet 1. First guide rails 15 are installed on both sides of the partition 14, and a handcart is placed on each guide rail 15. The handcart includes a chassis 16 and a circuit breaker 17, and is located within the circuit breaker compartment 12. Two handles 162 are provided on the chassis 16, which can move slightly left and right to engage or disengage with the first guide rails. A handcart rocker arm 161 is located between the two handles. By cranking the handcart rocker arm 161, the circuit breaker 17 can be moved relative to the chassis 16, allowing the circuit breaker to be positioned in different locations such as maintenance, testing, and operation. When the circuit breaker is in the maintenance position, the handcart can be pulled out of the central switch cabinet by pulling the handle 162 on the chassis and placed on the transfer cart 2 that is matched with the switch cabinet, so as to facilitate the maintenance of the circuit breaker.

[0035] The structure of the transfer cart 2 that is matched with the switch cabinet 1 is as follows: Figures 10-13 As shown, the transfer vehicle 2 includes a base frame 21, which has a box-like structure. Four casters 22 are installed under the base frame 21 to facilitate the movement of the transfer vehicle. Four handwheels 24 are provided above the base frame 21, and a vertical lead screw 23 is provided through each handwheel 24. A horizontally arranged support plate 25 is fixedly connected above the lead screw 23. The level and height of the support plate 25 can be adjusted by rotating the handwheels 24. Second guide rails 27 are fixedly provided on both sides of the support plate 25. A limit hole 271 is provided at one end of the second guide rail 27 to facilitate engagement with the handle of the transfer vehicle. At the same time, a limit block 254 is fixedly provided on the support plate at the rear end of the second guide rail. The limit block can prevent the transfer vehicle from moving excessively and prevent the transfer vehicle from falling when it is transferred.

[0036] The front and rear sides of the transfer vehicle support plate 25 are both bent vertically downward to form a front bent part 252 and a rear bent part 251. Guide shafts 253 are symmetrically arranged on both sides of the front bent part 252. A front nut 2521 and a rear nut 2511 are fixedly arranged on the inner side of the middle of the front bent part 252 and the rear bent part 251, respectively. The front and rear nuts have the same specifications and models. A horizontally positioned transfer cart rocker arm 26 is threaded through the middle of the front and rear bends. A worm gear section 261 is located on the side of the transfer cart rocker arm 26 near the front bend. Threaded sections, namely a front threaded section 262 and a rear threaded section 263, are located at both ends of the transfer cart rocker arm 26. The front threaded section 262 and the rear threaded section 263 are respectively threadedly connected to the front nut 2521 and the rear nut 2511. A rocker arm 264 is located at the end of the transfer cart rocker arm 26, outside the rear bend. The rocker arm's rocker arm has the same rocker arm shape as the handcart rocker arm, allowing them to share a single handle to save on parts and prevent confusion due to excessive handles. Limiting pins 265 are located at both ends of the rear threaded section 263 of the transfer cart rocker arm, passing through the shaft of the transfer cart rocker arm. The two limit pins 265 limit the axial movement of the rocker arm, preventing it from disengaging from the front and / or rear bends due to excessive rotation. Inserting the handle into the trolley's headstock and rotating it causes the rocker arm to rotate. Because the front and rear nuts are fixed, the rocker arm experiences axial displacement while rotating.

[0037] A turbine box 28 is fixedly installed below the support plate 25 of the transfer vehicle, near the front bend. Figures 11-14 A worm gear 281 is installed inside the turbine housing 28. A transfer cart rocker arm 26 passes through the turbine housing 28, and the worm section 261 on the rocker arm meshes with the worm gear 281. A rotating shaft 282 is fixedly installed at the center of the worm gear, and a gear 283 is coaxially fixedly connected to the rotating shaft 282. A rack seat 285 is vertically fixed below the support plate 25, and a rack 284 is slidably engaged on the rack seat 285. The rack 284 meshes with the gear 283, and driven by the gear 283, the rack 284 can slide up and down along the rack seat 285, and the rack 284 can pass through or out of the support plate 25. Figures 10-14 Only one set of gear and rack structure is shown. If a gear is connected to each end of the shaft 282 that passes through the worm gear, and each gear drives a rack, then the synchronous lifting and lowering of the two sets of racks can be achieved. The lifting and lowering principle is the same as that of a single rack, so it will not be described in detail.

[0038] To ensure a reliable and secure connection between the transfer cart 2 and the cabinet 1, the cabinet 1 requires special design. For example... Figures 5-9As shown, the outer side of the partition 14 is bent vertically downward to form a first bend 141. A pair of guide holes 142 are symmetrically arranged on both sides of the first bend 141. A first through hole 143 is arranged in the center of the first bend. A first nut 149 is fixedly arranged on the inner side of the first bend. The first nut 149 is coaxial with the first through hole 143. The first nut 149 has the same specifications and model as the front nut 2521 on the transfer vehicle. The guide holes 142 are matched and corresponding to the guide shafts 253 on the transfer vehicle. When the two guide shafts 253 of the transfer vehicle are aligned axially with the two guide holes 142 of the cabinet, the rocker arm 26 of the transfer vehicle, the front nut 2521 and the first nut 149 of the cabinet are also aligned axially, so that the transfer vehicle 2 can dock with the cabinet 1.

[0039] A second through hole 144 is provided on the upper surface of the partition plate 14 near the first bend 141. A guide sleeve 140 is fixedly provided below the partition plate 14, and the guide sleeve 140 is coaxially connected with the second through hole 144. A limiting post 145 is movably placed inside the guide sleeve 140, and the lower surface of the limiting post 145 is a first inclined surface 1451. An L-shaped support plate 146 is fixedly provided below the partition plate near the first bend. An upwardly protruding slide rail 1461 is provided at the center of the bottom surface of the L-shaped support plate 146, and a slider 147 is matched on the slide rail 1461. A groove 1473 is provided on the bottom surface of the slider 47. The groove 1473 cooperates with the slide rail 1461, allowing the slider to slide left and right. The left side of the slider 147 abuts against the first nut 149, and the right side of the slider 147 is connected to the vertical surface of the L-shaped bracket plate through the spring 148. A second inclined surface 1471 and a third inclined surface 1472 are provided on the slider 147. The side of the second inclined surface 1471 closer to the first nut 149 is lower than the side closer to the spring 148. The second inclined surface 1471 of the slider is in parallel contact with the first inclined surface 1451 of the limiting post 145. When the rocker arm 26 of the transfer vehicle is rocked through the first nut 149, it pushes the slider 147 to the right, compressing the spring 148. Simultaneously, the rightward movement of the second inclined surface 1471 on the slider causes the limiting post 145 to descend vertically under gravity. When the limiting post 145 touches the third inclined surface 1472, it cannot descend further. At this point, the limiting post blocks the slider 147, preventing it from moving further to the right; that is, the third inclined surface limits the slider's displacement. When the rocker arm is rocked out in the opposite direction from the first nut, the slider 147 moves to the left under the elastic restoring force of the spring 148, using the second inclined surface 1471 to push the limiting post 145 upward, protruding onto the upper surface of the partition plate 14.

[0040] When it is necessary to remove the handcart from the central switchgear, the handcart transfer method and principle are as follows:

[0041] First, attach the crank handle to the handcart crank 161, turn the crank handle to move the circuit breaker 17 to the maintenance position, and then remove the crank handle.

[0042] The second step is to open the circuit breaker compartment door of the central switchgear, move the transfer cart 2 to the front of the switchgear cabinet 1, adjust the height of the transfer cart support plate 25 so that the two guide shafts 253 of the transfer cart are horizontally inserted into the guide holes 142 of the cabinet partition, and make the front bend 252 of the transfer cart abut against the first bend 141 of the cabinet. At this time, the second guide rail 27 of the transfer cart is aligned with the first guide rail 15 of the cabinet, as shown in the figure. Figure 4 As shown.

[0043] Third, attach the crank handle to the rocker arm 264 of the transfer cart. Turn the crank handle to move the rocker arm 26 forward, passing through the first through hole 143 of the partition plate in the cabinet and being threadedly fixed to the first nut 149, thus reliably locking the transfer cart 2 to the switch cabinet 1 and preventing accidental disengagement. Continue turning the crank handle to make the head of the rocker arm pass through the first nut 149 and press the slider 147 to move backward along the slide rail 1461. The spring 148 is compressed, and at the same time, it is limited by the second inclined surface 1471 of the slider. Under its own weight, column 145 descends, and the top surface of the limiting column descends below the upper plane of the partition plate, so the limiting column no longer obstructs the pulling out of the handcart. In this step, the inclined surface between the slider and the limiting column is used to drive the raising and lowering of the limiting column, which serves two purposes: first, it indicates whether the transfer cart rocker arm and the first nut are threadedly locked in place, because the limiting column will only rise and fall if the rocker arm passes through the first nut; second, only after the limiting column descends can the handcart be pulled out of the cabinet, thus removing the obstruction to the handcart. While the transfer cart rocker arm rotates, the worm gear section 261 on the rocker arm drives the worm wheel 281 to rotate. The worm wheel 281 drives the rotating shaft 282 and the gear 283 to rotate. The gear 283 drives the rack 284 to descend, so that the upper end of the rack 284 is lower than or level with the upper surface of the support plate 25, and the rack no longer obstructs the handcart from entering the transfer cart. Since the rack protrudes from the upper surface of the transfer car support plate without the handcart in its initial state, it indicates that a reliable connection has not been formed between the transfer car and the switchgear, and the conditions for loading are not met. Only when the rack is lowered and hidden can the transfer car be ready to receive the handcart.

[0044] Fourth, pull the trolley handle 162 to move the trolley along the first guide rail 15 of the cabinet onto the second guide rail 27 of the transfer cart. After the trolley is completely transferred onto the transfer cart, push the trolley handle 162 outward to engage it with the limiting hole 271. Then, rotate the crank handle in the opposite direction to make the transfer cart crank 26 rotate backward. During the backward movement of the crank 26 and its disengagement from the first nut 149, the spring 148 pushes the slider 147 to move. The slider 147 pushes the limiting post 145 to rise and protrude again onto the surface of the cabinet's partition plate. At the same time as the transfer cart crank rotates in the opposite direction, the worm gear section 261 drives the worm wheel 281 to rotate. The worm wheel 281 drives the rotating shaft 282 and gear 283 to rotate. The gear 283 drives the rack 284 to rise, making the rack 284 protrude again onto the upper surface of the transfer cart support plate 25. The protruding rack can prevent the trolley from moving backward. Finally, push the transfer cart to move the entire trolley away from the front of the switch cabinet.

[0045] When the circuit breaker has been repaired and needs to be returned to the switchgear, move the transfer cart carrying the circuit breaker back to the front of the switchgear cabinet and repeat the second and third steps mentioned above to align the transfer cart with the switchgear. Lock the two together with the rocker arm. As the rocker arm is turned in, the rack and limit post descend. Then push the transfer cart into the cabinet. Finally, turn the rocker arm out in the opposite direction to release the lock between the transfer cart and the switchgear. Remove the transfer cart.

[0046] Therefore, the basic functions of this transfer cart are as follows: during the process of moving the circuit breaker into or out of the switchgear, the height of the transfer cart's guide rail is adjusted to smoothly align with the guide rail of the handcart inside the switchgear. The transfer cart and the switchgear are locked together by a rocker arm and a nut. The travel of the rocker arm, the lifting height of the rack, the travel of the slider, and the lifting height of the limit post are all coordinated and matched. During the transportation of the circuit breaker handcart, the transfer cart and the handcart are reliably limited to prevent the handcart from sliding or falling, ensuring safe and reliable transportation. Therefore, this invention achieves a robust interlocking connection between the centrally located switchgear and the transfer cart, which is beneficial for the safe transportation of the handcart and prevents accidents such as unhooking or tipping.

Claims

1. A centrally located switchgear, comprising a central partition plate horizontally fixed in the middle of the cabinet, first guide rails on both sides of the central partition plate, a handcart placed on the first guide rails, the handcart comprising a chassis and a circuit breaker, and a handcart crank mounted on the chassis, characterized in that: The outer side of the partition plate is bent vertically downward to form a first bend. Guide holes are symmetrically arranged on both sides of the first bend, and a first through hole is located at the center of the first bend. A first nut is fixedly installed on the inner side of the first bend, and the first nut is coaxial with the first through hole. A second through hole is located on the plane of the partition plate near the first bend. A guide sleeve is fixedly installed below the partition plate, and the guide sleeve is coaxial with the second through hole. A limiting post is movably placed inside the guide sleeve, and the lower surface of the limiting post is a first inclined surface. An L-shaped support plate is fixedly installed below the partition plate near the first bend. An upwardly protruding slide rail is located at the center of the bottom surface of the L-shaped support plate. A slider is fitted on the slide rail. One side of the slider abuts against the first nut, and the other side of the slider is connected to the vertical surface of the L-shaped support plate via a spring. A second inclined surface and a third inclined surface are provided on the slider. The side of the second inclined surface closer to the first nut is lower than the side closer to the spring. The second inclined surface of the slider is in parallel contact with the first inclined surface of the limiting post.

2. A centrally located switchgear according to claim 1, characterized in that: The cabinet is equipped with a transfer trolley, which includes a horizontally arranged support plate. Second guide rails are fixedly installed on both sides of the support plate. The front and rear sides of the support plate are vertically bent downwards to form a front bend and a rear bend. Guide shafts are symmetrically arranged on both sides of the front bend, and the guide shafts are correspondingly installed with guide holes. A front nut and a rear nut are fixedly installed on the inner side of the middle of the front bend and the rear bend, respectively. A transfer trolley rocker arm passes through the middle of the front bend and the rear bend. The transfer trolley rocker arm has two ends at its front and rear ends... Set separately Set The front and rear threaded sections of the rocker arm are connected to the front and rear nuts respectively via threaded connections. When the guide shaft and guide hole are aligned axially, the front nut and the first nut are also aligned axially, and the front nut and the first nut have the same specifications and model.

3. A centrally located switchgear according to claim 2, characterized in that: A worm gear box is fixedly installed below the support plate of the transfer vehicle, near the front bend. A worm gear is installed inside the worm gear box, and a rotating shaft is fixedly installed at the center of the worm gear. A gear is coaxially fixedly connected to the rotating shaft. A worm segment is installed in the middle of the rocker arm of the transfer vehicle, near the front bend. The rocker arm passes through the worm gear box, and the worm segment meshes with the worm gear. A rack seat is also vertically fixed below the support plate. A rack is slidably installed on the rack seat, meshing with the gear. The rack can pass through the support plate.

4. A centrally located switchgear according to claim 2, characterized in that: Limiting pins are provided at both ends of the rear threaded section of the transfer vehicle rocker arm, and the limiting pins pass through the body of the transfer vehicle rocker arm.

5. A centrally located switchgear according to claim 2, characterized in that: A rocker arm is provided at the end of the transfer vehicle rocker arm. The rocker arm of the transfer vehicle rocker arm has the same rocker arm shape as the handcart rocker arm, and the two can share a single crank handle.

Images