A load switch and ring main unit

Abstract

The present application relates to the technical field of load switch, and discloses a load switch and ring main unit. The load switch comprises a box body, a vacuum arc-extinguishing chamber, a disconnecting switch, an operating mechanism and a linkage mechanism. The middle transmission shaft is rotatably supported on the box body; the disconnecting switch rotating shaft drives the disconnecting switch to switch positions; and the load switch rotating shaft drives the vacuum arc-extinguishing chamber to open and close. The first transmission mechanism connects the operating mechanism and the middle transmission shaft, and the second transmission mechanism connects the operating mechanism and the disconnecting switch rotating shaft. In the closing operation, the rotation time sequence of the disconnecting switch rotating shaft is earlier than that of the middle transmission shaft; and in the opening operation, the rotation time sequence of the disconnecting switch rotating shaft is later than that of the middle transmission shaft. The present application can automatically realize the safe action sequence of "isolating first closing and vacuum second closing" and "vacuum first opening and isolating second opening" by one-time operation of the same operating mechanism, eliminates the risk of opening and closing the disconnecting switch with load, improves the operation safety and convenience, and has compact structure.

Description

Technical Field

[0001] This invention relates to the field of load switch technology, and more specifically, to a load switch and a ring main unit. Background Technology

[0002] A load switch is a mechanical switching device capable of closing, carrying, and interrupting current under normal circuit conditions, and capable of carrying abnormal circuit conditions (such as short-circuit current) for a specified time. In power distribution networks, it is widely used for line switching, control, and isolation.

[0003] To achieve reliable current interruption, traditional load switches often use sulfur hexafluoride (SF6) gas as both insulation and arc-quenching medium. However, SF6 is a potent greenhouse gas, and its leakage has a significant environmental impact. Therefore, the industry has turned to environmentally friendly gases (such as dry air, nitrogen, or other gas mixtures) as insulation media. However, since the insulation and arc-quenching performance of these environmentally friendly gases is generally inferior to that of SF6, technical solutions have generally shifted to a combined structure using a vacuum interrupter for current interruption, supplemented by a disconnector to form a visible isolation connection, thus balancing environmental and electrical performance requirements.

[0004] However, in the current industry, such environmentally friendly gas-insulated load switches often have separate operating mechanisms for the vacuum arc-extinguishing unit and the isolating switch, which are functionally independent. This means that a complete closing or opening operation needs to be performed in steps, which is cumbersome and results in a poor user experience. In order to prevent accidents caused by incorrect operation steps, a "five-proof" interlocking design is required between the mechanisms, which is complex. Moreover, this independent operation also makes such load switches large in size. Summary of the Invention

[0005] The problem solved by this invention is that in the prior art, the vacuum arc-extinguishing unit and the isolating switch of the gas-insulated load switch are functionally independent, and the operation is cumbersome and prone to misoperation.

[0006] To address the above problems, the present invention provides a load switch and a ring main unit.

[0007] In a first aspect, a load switch is provided, comprising: Vacuum interrupter; A disconnecting switch is connected in series with the vacuum interrupter. An operating mechanism is used to control the closing and opening operations of the vacuum interrupter and the disconnecting switch; The linkage mechanism includes a first transmission mechanism and a second transmission mechanism. The first transmission mechanism is connected between the operating mechanism and the vacuum interrupter; the second transmission mechanism is connected between the operating mechanism and the disconnecting switch. The first transmission mechanism has a first free travel in the closing operation direction and no free travel in the opening operation direction; the second transmission mechanism has a second free travel in the opening operation direction and no free travel in the closing operation direction; and the first free travel is greater than the second free travel.

[0008] Preferably, the load switch further includes: The enclosure, wherein the vacuum interrupter and the disconnecting switch are connected in series within the enclosure; The operating mechanism is located outside the housing; Preferably, the linkage mechanism further includes: a transfer drive shaft, a disconnect switch shaft, a load switch shaft, and a load transmission mechanism; the transfer drive shaft is rotatably supported outside the housing; the disconnect switch shaft is connected to the disconnect switch and is used to drive the disconnect switch to switch positions; the load switch shaft is connected to the vacuum interrupter and is used to drive the vacuum interrupter to open and close; the first transmission mechanism connects the operating mechanism and the transfer drive shaft; the second transmission mechanism connects the operating mechanism and the disconnect switch shaft; the transfer drive shaft and the load switch shaft are connected by the load transmission mechanism.

[0009] Preferably, the first transmission mechanism includes a first crank, a first connecting rod, and a first rocker block, wherein the first crank is fixedly connected to the operating mechanism, and the first rocker block is fixedly connected to the transfer transmission shaft; One end of the first connecting rod is hinged to the first crank, and the other end is provided with an oblong hole; a first sliding post is fixedly provided on the first rocker block, and the first sliding post passes through the oblong hole. The length of the oblong hole is greater than the diameter of the first sliding post, and the length difference between the two forms the first idle stroke. The first transmission mechanism also includes an auxiliary spring, one end of which is fixed to the housing and the other end of which elastically abuts against the first rocker block; When the operating mechanism performs a closing operation, the first sliding column abuts against one end of the waist-shaped hole, and the first rocker rotates to compress the auxiliary spring; when the operating mechanism performs a opening operation, the first sliding column disengages from one end of the waist-shaped hole, the auxiliary spring extends and drives the first rocker to rotate in the opposite direction.

[0010] Preferably, the second transmission mechanism includes a first actuating element and a second rocking block, the first actuating element being fixedly connected to the operating mechanism, and the second rocking block being fixedly connected to the rotating shaft of the disconnecting switch; The first actuating element is provided with a first U-shaped groove; the second rocker block is fixedly provided with a second sliding post, the second sliding post passes through the first U-shaped groove and can slide along the groove wall of the first U-shaped groove, and there is a gap between the second sliding post and the groove wall of the first U-shaped groove, the width of the gap forming the second free stroke.

[0011] Preferably, the load switch further includes a base plate and a connecting post. The base plate is installed outside the housing, the connecting post is installed on the base plate, one end of the auxiliary spring is connected to the connecting post, and the other end elastically abuts against the first rocker block.

[0012] Preferably, the load transmission mechanism includes: a second crank, a second connecting rod, and a crank arm, wherein the second crank is fixedly connected to the transfer drive shaft, the crank arm is fixedly connected to the load switch shaft, and the two ends of the second connecting rod are respectively hinged to the second crank and the crank arm.

[0013] Preferably, the operating mechanism includes a load operating shaft and a drive assembly, wherein both the first transmission mechanism and the second transmission mechanism are connected to the load operating shaft; the drive assembly includes a connecting plate and a drive motor, wherein the connecting plate is connected to the load operating shaft, and the drive motor is drivenly connected to the connecting plate.

[0014] Preferably, the load switch further includes a grounding operating shaft, wherein the grounding operating shaft and the disconnecting switch rotating shaft are respectively located on opposite sides of the transfer drive shaft; A second actuating element is fixedly connected to the grounding operating shaft, a third sliding column is provided on the second rocker block, a second U-shaped groove is provided on the second actuating element, and the third sliding column passes through the second U-shaped groove.

[0015] Secondly, a ring main unit is provided, including a cabinet and the aforementioned load switch, wherein the load switch is installed inside the cabinet.

[0016] The beneficial effects of the load switch of the present invention are: This invention precisely locks the closing and opening sequence of the circuit breaker by setting opposite free travel directions in the first and second transmission mechanisms, and limiting the first free travel to be greater than the second free travel. Specifically, without relying on any electrical interlocks, the closing and opening sequence is precisely locked mechanically. When the operating mechanism performs a closing operation, since the second transmission mechanism has no free travel in the closing direction, the closing action immediately drives the isolating switch to close first. However, the first transmission mechanism has a first free travel in the closing direction, delaying the closing action of the vacuum interrupter. The vacuum interrupter closes only after the isolating switch is fully closed. This automatically achieves the safe sequence of "isolation first, vacuum then closing," preventing the isolating switch from closing under load. When the operating mechanism performs a opening operation, since the first transmission mechanism has no free travel in the opening direction, the opening action immediately drives the vacuum interrupter to disconnect the current first. However, the second transmission mechanism has a second free travel in the opening direction, delaying the opening action of the isolating switch. The isolating switch opens only after the vacuum interrupter has completely extinguished the arc and disconnected. This automatically achieves the safe sequence of "vacuum first, isolation later", ensuring that the disconnecting switch forms a visible isolation break under no-current conditions.

[0017] The aforementioned timing control is entirely determined by the idle travel characteristics of the transmission mechanism itself. The operator only needs to perform one closing or opening operation on a single operating mechanism to automatically complete the complete action sequence that complies with power safety regulations. This fundamentally eliminates major safety accidents caused by incorrect operation sequence when opening or closing disconnecting switches under load, and significantly improves the operational safety of load switches. Attached Figure Description

[0018] Figure 1 This is a three-dimensional schematic diagram of the load switch of the present invention; Figure 2 This is a three-dimensional schematic diagram of the load switch of the present invention from another perspective; Figure 3 This is a schematic diagram of the external portion of the load switch box of the present invention; Figure 4 for Figure 3 The diagram shown is a schematic representation of the structure after concealing the auxiliary spring and drive assembly. Figure 5 for Figure 4 The front view of the structure shown; Figure 6 for Figure 4 The diagram shown is a schematic of the structure with the first crank and first connecting rod hidden, and the auxiliary spring displayed. Figure 7 for Figure 1 The structure shown is a cross-sectional view along AA; Figure 8 for Figure 2The structure shown is a cross-sectional view along BB.

[0019] Explanation of reference numerals in the attached figures: 1. Housing; 2. Vacuum interrupter; 3. Transfer drive shaft; 4. Disconnect switch shaft; 5. Load switch shaft; 6. Load operating shaft; 7. First crank; 8. First connecting rod; 9. First rocker block; 10. Waist-shaped hole; 11. First sliding column; 12. First actuating element; 13. Second rocker block; 14. First U-shaped slot; 15. Second sliding column; 16. Base plate; 17. Auxiliary spring; 18. Second crank; 19. Second connecting rod; 20. Crank arm; 21. Connecting plate; 22. Drive motor; 23. Grounding operating shaft; 24. Second actuating element; 25. Third sliding column; 26. Second U-shaped slot; 27. Upper busbar; 28. Movable blade plate; 29. ​​Upper isolating contact; 30. Lower isolating contact; 31. Grounding contact; 32. Lower conductor; 33. Connecting column. Detailed Implementation

[0020] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the accompanying drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0021] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to"; the term "based on" means "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; and the term "optionally" means "optional embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first," "second," etc., mentioned in this invention are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0022] It should be noted that the terms "a" and "a plurality of" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0023] Example 1 This invention provides a load switch suitable for ring network power supply or terminal distribution systems, used to connect, carry, and disconnect current under normal and abnormal circuit conditions, while providing a visible isolation contact to ensure maintenance safety. Figures 1-8 As shown, the load switch mainly includes a housing 1, a vacuum interrupter 2, a disconnecting switch, an operating mechanism, and a linkage mechanism.

[0024] Specifically, the housing 1 serves as the supporting and protective structure for the entire switch, forming a sealed cavity that can be filled with environmentally friendly insulating gases such as dry air and nitrogen to provide an insulating and arc-extinguishing environment. The vacuum interrupter 2 (vacuum switch tube) and the disconnector switch are connected in series inside the housing 1, forming the main circuit path. The vacuum interrupter 2 is a switching device that uses vacuum as the arc-extinguishing medium, achieving current connection and disconnection through the closing and opening of contacts. The disconnector switch has three operating positions: closed, open, and grounded. When in the open position, it forms a visible electrical isolation break; when in the grounded position, it reliably grounds the main circuit. In some embodiments, the disconnector switch may only have closed and open positions.

[0025] The operating mechanism is installed outside the housing 1 and is used to provide operating power for the entire switch. The operating mechanism can be in the form of manual energy storage, electric energy storage, or electromagnetic drive, and is driven by human power or an electric motor to drive the internal energy storage spring or transmission components, thereby outputting a specified motion trajectory and operating force.

[0026] The linkage mechanism is also located outside the housing 1 and connected to the operating mechanism. It is also connected to the vacuum interrupter 2 and the disconnecting switch via transmission components. The core function of the linkage mechanism is to coordinate the timing of the actions of the vacuum interrupter 2 and the disconnecting switch. Specifically, during the closing operation, the operating mechanism drives the linkage mechanism. The linkage mechanism first drives the disconnecting switch from the open position to the closed position, and then drives the vacuum interrupter 2 to complete the closing action, thus connecting the main circuit. During the opening operation, the operating mechanism drives the linkage mechanism in the reverse direction. The linkage mechanism first drives the vacuum interrupter 2 to quickly open to extinguish the arc, and then drives the disconnecting switch from the closed position to the open position, forming a visible isolation break. If necessary, it can be further switched to the grounding position.

[0027] It should be noted that there are various ways to achieve the above-mentioned timing control through the linkage mechanism. For example, it can be achieved through mechanical structures such as connecting rods of different lengths, slotted holes with idle strokes, gear sets with different transmission ratios, or phase differences in the cam profile, or through electrical control, so that the two controlled objects have a sequential order in time. Those skilled in the art can choose an appropriate implementation method according to actual needs, as long as it can ensure that the closing and opening sequence of the disconnecting switch and the vacuum interrupter 2 meets the safety requirements.

[0028] In summary, the load switch in this embodiment integrates the vacuum interrupter 2 and the disconnector switch, and uses a linkage mechanism to precisely control the timing of their operation. During closing, the disconnector switch closes first, followed by the vacuum interrupter 2, thus preventing the disconnector switch from handling the load current. During opening, the vacuum interrupter 2 interrupts the current first, followed by the disconnector switch, ensuring the disconnector switch forms an isolation break under no-current conditions. This sequential coordination fundamentally eliminates the risk of misoperation when opening or closing the disconnector switch under load, significantly improving the operational safety and reliability of the load switch. Furthermore, safe closing and opening can be achieved with a single operation by the operating mechanism, making operation convenient and quick. This linkage operation method also facilitates compact layout and miniaturized design, making it suitable for application in equipment such as ring main units.

[0029] As a further implementation, the linkage mechanism is further defined. This linkage mechanism mainly consists of a transfer drive shaft 3, a disconnector switch shaft 4, a load switch shaft 5, a first transmission mechanism, a second transmission mechanism, and a load transmission mechanism. The transfer drive shaft 3, as the central element for motion transmission and timing distribution, is rotatably supported outside the housing 1. The disconnector switch shaft 4 is connected to the disconnector switch drive component inside the housing 1, used to drive the disconnector switch to switch between the closed, open, and grounded positions. The load switch shaft 5 is connected to the moving end conductive rod of the vacuum interrupter 2 via an insulating pull rod and other components, used to drive the vacuum interrupter 2 to complete the closing or opening action. The transfer drive shaft 3, disconnector switch shaft 4, and load switch shaft 5 are arranged in parallel and can each rotate around its own axis.

[0030] In terms of connection, the first transmission mechanism is connected between the operating mechanism and the intermediate transmission shaft 3, used to transmit the input motion of the operating mechanism to the intermediate transmission shaft 3. Simultaneously, the intermediate transmission shaft 3 and the load switch shaft 5 are maintained in a transmission connection through a load transmission mechanism, so that the rotation of the intermediate transmission shaft 3 can drive the load switch shaft 5 to move accordingly. The second transmission mechanism is connected between the operating mechanism and the disconnect switch shaft 4, used to directly transmit the input motion of the operating mechanism to the disconnect switch shaft 4. That is, the operating mechanism, through the first and second transmission mechanisms, ultimately drives the load switch shaft 5 and the disconnect switch shaft 4 to move.

[0031] In this system, the intermediate drive shaft 3 serves as the central hub for timing allocation. The first transmission mechanism transmits the motion of the operating mechanism to the intermediate drive shaft 3, and the load transmission mechanism then transmits the motion of the intermediate drive shaft 3 to the load switch rotating shaft 5, thereby driving the vacuum interrupter 2 to operate. The second transmission mechanism directly transmits the motion of the operating mechanism to the disconnector rotating shaft 4, driving the disconnector to operate. The first and second transmission mechanisms are independently configured, and the intermediate drive shaft and load transmission mechanism allow for flexible spatial arrangement of the vacuum interrupter and the disconnector, achieving spatial decoupling between the two.

[0032] More importantly, the first and second transmission mechanisms have different motion transmission characteristics, allowing for a difference in the rotation sequence of the disconnector shaft 4 and the intermediate transmission shaft 3 when the operating mechanism is activated. Specifically, during the closing operation, the disconnector shaft 4 responds first and drives the disconnector to the closed position, followed by the intermediate transmission shaft 3 driving the vacuum interrupter 2 to close via its transmission connection with the load switch shaft 5. During the opening operation, the intermediate transmission shaft 3 responds first and drives the vacuum interrupter 2 to open quickly via the load switch shaft 5, followed by the disconnector shaft 4 driving the disconnector to the open position. By setting the first and second transmission mechanisms with different motion transmission characteristics between the intermediate transmission shaft 3, the disconnector shaft 4, and the operating mechanism, precise control of the operating sequence of the disconnector and the vacuum interrupter 2 is cleverly achieved. This structural design eliminates the need for complex electrical interlocks or manual sequential operations. It ensures the safe operating sequence of "closing the isolator first, then closing the vacuum" and "disconnecting the vacuum first, then disconnecting the isolator" through purely mechanical means. This effectively avoids the safety hazards of opening and closing isolating switches under load, significantly improves the reliability and safety of load switches, and is compact, low-cost, and easy to promote and apply.

[0033] As a further embodiment, the internal structure of the housing 1 will be described. For example... Figure 7 and Figure 8 As shown, inside the enclosure 1, power is introduced from the upper busbar 27, passing through the vacuum interrupter 2 and the disconnecting switch from top to bottom, and finally exiting from the lower conductor 32 to the load or cable. Specifically, an upper busbar 27 is provided at the top inside the enclosure 1. This upper busbar 27 is used to connect to the external power supply and is usually made of copper or aluminum busbars, with sufficient current carrying capacity. The upper busbar 27 is electrically connected to the stationary conductive rod of the vacuum interrupter 2, introducing power into the vacuum interrupter 2.

[0034] The vacuum interrupter 2 is a switching device that uses high vacuum as the arc-extinguishing medium. It contains a stationary contact and a moving contact. The stationary contact is connected to a stationary conductive rod, and the moving contact is connected to a moving conductive rod. The axial movement of the moving contact allows for the closing and opening of the stationary contact, thereby connecting or disconnecting the current. The moving conductive rod of the vacuum interrupter 2 is connected to the load switch shaft 5 via an insulating pull rod and other components. The rotation of the load switch shaft 5 drives the axial movement of the moving conductive rod. The moving conductive rod of the vacuum interrupter 2 is further electrically connected to the isolating upper contact 29.

[0035] The disconnector switch mainly includes a movable blade plate 28, an upper isolating contact 29, a lower isolating contact 30, and a grounding contact 31. The upper isolating contact 29 is fixed inside the housing 1 and electrically connected to the vacuum interrupter 2; the lower isolating contact 30 is fixed inside the lower part of the housing 1 and electrically connected to the lower conductor 32; the grounding contact 31 is located inside the housing 1 and is used to connect to the grounding system. The movable blade plate 28, as the moving contact of the disconnector switch, is fixedly connected to the disconnector switch shaft 4. Driven by the disconnector switch shaft 4, it can contact the upper isolating contact 29, the lower isolating contact 30, or the grounding contact 31 in different scenarios. Specifically, when both the vacuum interrupter 2 and the disconnector switch are in the closed position, current flows in from the upper busbar 27, passes through the vacuum interrupter 2, enters the upper isolating contact 29, then flows through the movable blade plate 28 and the lower isolating contact 30 into the lower conductor 32, and finally outputs to the load, forming a complete main circuit path. When both the vacuum interrupter 2 and the disconnecting switch are in the open position, the movable blade 28 is disconnected from the upper isolating contact 29. When the disconnecting switch is in the grounding position, both ends of the movable blade 28 are connected to the lower isolating contact 30 and the grounding contact 31, respectively, to achieve reliable grounding.

[0036] As a further embodiment, the timing relationship between the first transmission mechanism and the second transmission mechanism will be explained. For example... Figures 3-6 As shown, specifically, the operating mechanism includes a load operating shaft 6, which is the power output element of the operating mechanism, used to transmit operating force to subsequent transmission components. Both the first and second transmission mechanisms are connected to this load operating shaft 6; that is, the load operating shaft 6 serves as the common input end of the two transmission mechanisms, simultaneously transmitting the motion of the operating mechanism to both the first and second transmission mechanisms.

[0037] More importantly, this embodiment includes a no-travel section, enabling timing control of the vacuum interrupter 2 and the disconnector. The "no-travel section" refers to an ineffective segment within the motion transmission path. When the driving component begins to move, the driven component does not respond immediately; instead, it establishes contact and begins to move only after the driving component has traveled a certain distance. This structure provides a concrete and reliable mechanical implementation for motion timing control.

[0038] In this embodiment, the first transmission mechanism has a first idle stroke in the closing operation direction and no idle stroke in the opening operation direction, thereby achieving delayed motion transmission to the transfer drive shaft 3 during closing operation and immediate motion transmission during opening operation. The second transmission mechanism has a second idle stroke in the opening operation direction and no idle stroke in the closing operation direction, achieving delayed motion transmission to the disconnector shaft 4 during opening operation and immediate motion transmission during closing operation. In this embodiment, the closing operation direction is counterclockwise and the opening operation direction is clockwise. Specifically, during the closing operation, the load operating shaft 6 rotates counterclockwise. The second transmission mechanism has no idle stroke in the closing operation direction and does not generate a delay. Therefore, the disconnector shaft 4 responds immediately and drives the disconnector to switch to the closing position first. At the same time, the first transmission mechanism has a first idle stroke in the closing operation direction, thus generating a delay, causing the transfer drive shaft 3 to temporarily not rotate. After the first idle stroke is completed, the transfer drive shaft 3 begins to rotate and drives the vacuum interrupter 2 to close the circuit. During the tripping operation, the load operating shaft 6 rotates in the reverse direction. The first transmission mechanism has no idle travel in the tripping operation direction and produces no delay, immediately driving the transfer transmission shaft 3 to rotate and causing the vacuum interrupter 2 to begin tripping. Simultaneously, the second transmission mechanism has a second idle travel in the tripping operation direction, thus producing a delay in that direction. This causes the disconnector shaft 4 to temporarily stop rotating until the second idle travel is completed, at which point the disconnector begins to switch to the tripping position. Furthermore, because the length of the first idle travel is greater than the second idle travel, it ensures that the vacuum interrupter 2 has sufficient displacement to complete the current interruption during tripping, while the disconnector has not yet activated, thereby ensuring the safety and reliability of the tripping sequence.

[0039] It is precisely this directional design of the idle travel and the difference in travel length that precisely realizes "different motion transmission characteristics", thereby ensuring that the disconnecting switch and vacuum interrupter 2 follow the safe sequence of "disconnecting first, vacuum then closing" during the closing process and "vacuum first, disconnecting later" during the opening process.

[0040] As a further embodiment, the first transmission mechanism will be described. Specifically, as follows: Figures 3 to 5 As shown, the first transmission mechanism mainly consists of a first crank 7, a first connecting rod 8, and a first rocker block 9, forming a crank-rocker block mechanism. The first crank 7 serves as the power input end and is fixedly connected to the load operating shaft 6 of the operating mechanism, for example, through a key connection, pin connection, or welding, allowing the first crank 7 to rotate synchronously with the load operating shaft 6. The first rocker block 9 serves as the power output end and is fixedly connected to the intermediate transmission shaft 3, used to transmit motion to the intermediate transmission shaft 3.

[0041] In terms of connection, one end of the first connecting rod 8 is hinged to the first crank 7, meaning that the rotation of the first crank 7 can drive the first connecting rod 8 to move; for example Figure 5 and Figure 6 As shown, the other end of the first connecting rod 8 is provided with an oblong hole 10, which extends along the length of the first connecting rod 8. Simultaneously, a first sliding post 11 is fixedly provided on the first rocker block 9. The first sliding post 11 passes through the oblong hole 10 of the first connecting rod 8 and can slide along the oblong hole 10. More importantly, the length of the oblong hole 10 is designed to be greater than the diameter of the first sliding post 11, and the difference between the length of the oblong hole 10 and the diameter of the first sliding post 11 forms the first idle stroke. Furthermore, it should be noted that the width of the oblong hole 10 is also greater than the diameter of the first sliding post 11, allowing the first sliding post 11 to slide within the oblong hole 10.

[0042] During the closing operation (load operating shaft 6 rotates counterclockwise), the first crank 7 drives the first connecting rod 8 to move. Due to the existence of the first idle stroke, the first sliding column 11 slides relative to the first rocker block 9 within the oblong hole 10, and does not immediately push the first rocker block 9. Therefore, the intermediate transmission shaft 3 remains stationary, realizing the delayed closing of the vacuum interrupter during closing. When the load operating shaft 6 rotates counterclockwise through a certain angle, the right end of the oblong hole 10 contacts the first sliding column 11 and applies force, i.e., as... Figure 4 , Figure 5 As shown, the first sliding column 11 is initially pushed, which in turn drives the first rocker block 9 to rotate, which in turn drives the intermediate transmission shaft 3 to rotate, thereby closing the vacuum interrupter chamber 2. As the first rocker block 9 rotates, the auxiliary spring 17 is compressed and stores its elastic force until the closing is completed; the auxiliary spring 17 remains in a compressed state throughout. During the opening operation (the load operating shaft 6 rotates clockwise), the first crank 7 swings in the opposite direction, and the first connecting rod 8 moves in the opposite direction accordingly. At this time, the first sliding column 11 disengages from the right end of the oblong hole 10 and is no longer pushed by the right end of the oblong hole 10. The auxiliary spring 17 releases its elastic force and drives the first rocker block 9 to immediately rotate in the opposite direction, which in turn drives the intermediate transmission shaft 3 to rotate, thus achieving the opening. Until the opening is completed, the auxiliary spring 17 extends to its initial state.

[0043] As a further embodiment, the second transmission mechanism will be described. For example... Figure 6 As shown, specifically, the second transmission mechanism mainly consists of a first actuating element 12 and a second rocker block 13. The first actuating element 12 serves as the power input end and is fixedly connected to the load operating shaft 6 of the operating mechanism, for example, through a key connection, pin connection, or welding, allowing the first actuating element 12 to rotate synchronously with the load operating shaft 6. The second rocker block 13 serves as the power output end and is fixedly connected to the disconnecting switch rotating shaft 4, used to transmit motion to the disconnecting switch rotating shaft 4, thereby driving the disconnecting switch to switch between the closed, open, and grounded positions.

[0044] In terms of connection, the first actuating member 12 is provided with a first U-shaped groove 14, and the second rocker block 13 is fixedly provided with a second sliding post 15. The second sliding post 15 passes through the first U-shaped groove 14 of the first actuating member 12 and can slide along the groove wall of the first U-shaped groove 14. A gap is provided between the second sliding post 15 and the groove wall of the first U-shaped groove 14, and the width of the gap forms the second free stroke.

[0045] like Figures 3-6 As shown, during the closing operation (the load operating shaft 6 rotates counterclockwise), the upper side of the first U-shaped slot 14 will inevitably contact the second sliding column 15 first, while the lower side of the first U-shaped slot 14 will maintain a gap with the second sliding column 15. That is, the second transmission mechanism is in the second free stroke in the opening operation direction and has no free stroke in the closing operation direction. Continuing to rotate the load operating shaft 6, the first actuating member 12 rotates counterclockwise with the load operating shaft 6. Through the interaction of the first U-shaped slot 14 and the second sliding column 15, the second rocker block 13 rotates, which in turn drives the isolating switch shaft 4 to rotate clockwise, switching the isolating switch to the closing position. Simultaneously, because the first transmission mechanism has a large first free stroke, it is still in the free stroke stage, and the vacuum interrupter has not yet activated, thus achieving "isolation first, vacuum then closing".

[0046] During the tripping operation (load operating shaft 6 rotates clockwise), the first actuating member 12 rotates clockwise accordingly. Since the lower side of the first U-shaped slot 14 previously maintained a gap with the second sliding column 15, the second rocker block 13 remains stationary until this gap is completely closed, and the disconnecting switch shaft 4 does not rotate, thus achieving delayed control of the disconnecting switch during tripping. Simultaneously, the load operating shaft 6 drives the first crank 7 and the first connecting rod 8, causing the force applied to the first rocker block 9 to disappear. Therefore, the first rocker block 9 can immediately actuate under the action of the auxiliary spring 17, realizing the tripping of the vacuum interrupter. After the vacuum interrupter is disconnected, the load operating shaft 6 continues to rotate, and the lower side of the U-shaped slot contacts and applies force to the second sliding column 15, causing the second rocker block 13 to begin rotating, driving the disconnecting switch to the tripped position.

[0047] As a further implementation, the first transmission mechanism is optimized. For example... Figure 3 , Figure 6As shown, the load switch in this embodiment also includes a base plate 16 and a connecting post 33. The base plate 16 is fixedly installed on the outside of the housing 1 and connected to the housing 1 by bolts, serving as the mounting base for the auxiliary spring 17 and providing it with a stable support point. To facilitate the installation of the auxiliary spring 17, a connecting post 33 is fixedly installed on the base plate 16. One end of the auxiliary spring 17 is connected to the connecting post 33, and the other end elastically abuts against the first rocker block 9.

[0048] As a further embodiment, the load transmission mechanism is described. Specifically, the load transmission mechanism mainly consists of a second crank 18, a second connecting rod 19, and a crank arm 20. The second crank 18 serves as the power input end and is fixedly connected to the intermediate transmission shaft 3, for example, through a key connection, pin connection, or welding, allowing the second crank 18 to rotate synchronously with the intermediate transmission shaft 3. The crank arm 20 serves as the power output end and is fixedly connected to the load switch shaft 5, used to transmit motion to the load switch shaft 5, thereby driving the moving end conductive rod of the vacuum interrupter 2 to complete the closing or opening action. The second connecting rod 19 connects the second crank 18 and the crank arm 20, with its two ends hinged to the second crank 18 and the crank arm 20 respectively. That is, when the second crank 18 rotates, it drives the second connecting rod 19 to move, and the second connecting rod 19 in turn drives the crank arm 20 to swing. When the transfer drive shaft 3 rotates under the drive of the first transmission mechanism, the second crank 18, which is fixedly connected to it, rotates accordingly. This motion is transmitted to the crank arm 20 via the second connecting rod 19, causing the crank arm 20 to swing around the axis of the load switch shaft 5. Since the crank arm 20 is fixedly connected to the load switch shaft 5, the swinging of the crank arm 20 directly drives the load switch shaft 5 to rotate, which in turn drives the moving end conductive rod of the vacuum interrupter 2 to move axially through components such as the insulating pull rod, thus achieving the closing or opening of the vacuum interrupter 2. Specifically, when the second crank 18 rotates in one direction, it pushes the crank arm 20 to swing in the corresponding direction via the second connecting rod 19, causing the load switch shaft 5 to rotate and driving the vacuum interrupter 2 to close; when the second crank 18 rotates in the opposite direction, it pulls the crank arm 20 to swing in the opposite direction, causing the load switch shaft 5 to rotate in the opposite direction and driving the vacuum interrupter 2 to open.

[0049] It should be noted that the second crank 18, the second connecting rod 19, and the crank arm 20 together constitute the crank-connecting rod mechanism. By rationally designing the length and initial installation angle of each component, the stroke, speed characteristics, and opening / closing position requirements of the vacuum interrupter 2 can be met. For example, the transmission ratio and output angle range can be changed by adjusting the length of the second crank 18; the motion trajectory and force state can be optimized by adjusting the length of the second connecting rod 19; and the initial angle of the crank arm 20 can be adjusted to ensure that the vacuum interrupter 2 can reliably contact the circuit when closed and has sufficient opening distance when open.

[0050] As a further implementation method, the operating mechanism is optimized, such as... Figure 3 As shown, the operating mechanism includes a load operating shaft 6 for manual operation and also integrates a drive component to provide automated operation capability for the load switch.

[0051] Specifically, the drive assembly mainly includes a connecting plate 21 and a drive motor 22. The connecting plate 21 serves as an intermediate element for power transmission and is connected to the load operating shaft 6. This connection can take various forms; for example, the connecting plate 21 can be directly mounted on the load operating shaft 6 and fixed with a key or pin, allowing both to rotate synchronously; or the connecting plate 21 can establish a transmission relationship with the load operating shaft 6 through a coupling, gear drive, or chain drive. The function of the connecting plate 21 is to smoothly transmit the power of the drive motor 22 to the load operating shaft 6, and it also serves as a switching interface between manual and electric operation. When an electric closing or opening operation is required, the control system sends an operation command to the drive motor 22, which starts and outputs rotational power, driving the connecting plate 21 to rotate through the transmission connection. The connecting plate 21 then drives the load operating shaft 6 to rotate.

[0052] As a further implementation method, such as Figures 3 to 6 As shown, the load switch in this embodiment also includes a grounding operating shaft 23, which is set independently of the load operating shaft 6 and is used specifically to drive the disconnect switch to the grounded position. From the layout, as... Figure 5 As shown, the grounding operating shaft 23 and the disconnecting switch rotating shaft 4 are respectively arranged on opposite sides of the transfer drive shaft 3. This symmetrical layout can make full use of the space outside the housing 1 and avoid interference between the operating shafts.

[0053] A second actuating element 24 is fixedly connected to the grounding operating shaft 23, and the second actuating element 24 rotates synchronously with the grounding operating shaft 23. Simultaneously, a third sliding post 25 is provided on the second rocker block 13, and the third sliding post 25 is fixedly installed on the second rocker block 13. For example... Figure 6 As shown, the second actuating member 24 is provided with a second U-shaped groove 26, and the third sliding post 25 passes through the second U-shaped groove 26 and can slide along the groove wall of the second U-shaped groove 26.

[0054] like Figure 1 , Figure 5 and Figure 7As shown, when a grounding operation is required, the operator rotates the grounding operation shaft 23 clockwise, which drives the second actuating member 24 to rotate. The second actuating member 24 transmits the motion to the second rocker block 13 through the cooperation of the second U-shaped slot 26 and the third sliding column 25. The second rocker block 13 drives the disconnecting switch shaft 4 to rotate counterclockwise, thereby driving the disconnecting switch to switch from the current open position to the grounded position, that is, the two ends of the movable blade 28 are respectively connected to the lower isolating contact 30 and the grounding contact 31, so that the main circuit is reliably grounded.

[0055] Example 2 This embodiment provides a ring main unit that integrates the load switch described in Embodiment 1, forming a complete power distribution switchgear. When the ring main unit is put into operation, the load switch is closed by the operating mechanism on the cabinet. Current flows from the incoming busbar through the load switch's isolating switch and vacuum interrupter 2 to the outgoing cable, supplying power to the load. When line maintenance is required, following the opening operation procedure, the load switch first cuts off the current, then forms a visible isolation break, and can reliably ground the line side to ensure maintenance safety. The entire process is simple to operate and reliable in sequence, requiring no complex electrical interlocks or manual verification.

[0056] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A load switch, characterized in that, include: Vacuum interrupter (2); The isolating switch is connected in series with the vacuum interrupter (2); An operating mechanism is used to control the closing and opening operations of the vacuum interrupter (2) and the disconnecting switch; The linkage mechanism includes a first transmission mechanism and a second transmission mechanism. The first transmission mechanism is connected between the operating mechanism and the vacuum interrupter (2); the second transmission mechanism is connected between the operating mechanism and the disconnecting switch. The first transmission mechanism has a first free travel in the closing operation direction and no free travel in the opening operation direction; the second transmission mechanism has a second free travel in the opening operation direction and no free travel in the closing operation direction; and the first free travel is greater than the second free travel.

2. The load switch according to claim 1, characterized in that, Also includes: The enclosure (1), the vacuum interrupter (2) and the disconnecting switch are connected in series inside the enclosure (1); The operating mechanism is located outside the housing (1).

3. The load switch according to claim 2, characterized in that, The linkage mechanism further includes: a transfer drive shaft (3), a disconnect switch shaft (4), a load switch shaft (5), and a load transmission mechanism; the transfer drive shaft (3) is rotatably supported outside the housing (1); the disconnect switch shaft (4) is connected to the disconnect switch and is used to drive the disconnect switch to switch positions; the load switch shaft (5) is connected to the vacuum interrupter (2) and is used to drive the vacuum interrupter (2) to open and close; the first transmission mechanism connects the operating mechanism and the transfer drive shaft (3); the second transmission mechanism connects the operating mechanism and the disconnect switch shaft (4); the transfer drive shaft (3) and the load switch shaft (5) are connected by the load transmission mechanism.

4. The load switch according to claim 3, characterized in that, The first transmission mechanism includes a first crank (7), a first connecting rod (8) and a first rocker block (9). The first crank (7) is fixedly connected to the operating mechanism, and the first rocker block (9) is fixedly connected to the transfer transmission shaft (3). One end of the first connecting rod (8) is hinged to the first crank (7), and the other end is provided with a waist-shaped hole (10); a first sliding column (11) is fixedly provided on the first rocker block (9), the first sliding column (11) passes through the waist-shaped hole (10), the length of the waist-shaped hole (10) is greater than the diameter of the first sliding column (11), and the length difference between the two forms the first idle stroke; The first transmission mechanism also includes an auxiliary spring (17), one end of which is fixed to the housing (1), and the other end is elastically abutting against the first rocker block (9); When the operating mechanism performs a closing operation, the first sliding column (11) abuts against one end of the waist-shaped hole (10), and the first rocker block (9) rotates to compress the auxiliary spring (17); when the operating mechanism performs a opening operation, the first sliding column (11) disengages from one end of the waist-shaped hole (10), and the auxiliary spring (17) extends and drives the first rocker block (9) to rotate in the opposite direction.

5. The load switch according to claim 3, characterized in that, The second transmission mechanism includes a first actuating element (12) and a second rocker block (13). The first actuating element (12) is fixedly connected to the operating mechanism, and the second rocker block (13) is fixedly connected to the disconnecting switch shaft (4). The first actuating member (12) is provided with a first U-shaped groove (14); the second rocker block (13) is fixedly provided with a second sliding post (15), the second sliding post (15) passes through the first U-shaped groove (14) and can slide along the groove wall of the first U-shaped groove (14), and there is a gap between the second sliding post (15) and the groove wall of the first U-shaped groove (14), the width of the gap forming the second free stroke.

6. The load switch according to claim 4, characterized in that, It also includes a base plate (16) and a connecting post (33). The base plate (16) is installed outside the housing (1), and the connecting post (33) is installed on the base plate (16). One end of the auxiliary spring (17) is connected to the connecting post (33), and the other end is elastically abutted against the first rocker block (9).

7. The load switch according to claim 3, characterized in that, The load transmission mechanism includes a second crank (18), a second connecting rod (19), and a crank arm (20). The second crank (18) is fixedly connected to the intermediate transmission shaft (3), and the crank arm (20) is fixedly connected to the load switch shaft (5). The two ends of the second connecting rod (19) are respectively hinged to the second crank (18) and the crank arm (20).

8. The load switch according to claim 1, characterized in that, The operating mechanism includes a load operating shaft (6) and a drive assembly. The first transmission mechanism and the second transmission mechanism are both connected to the load operating shaft (6). The drive assembly includes a connecting disk (21) and a drive motor (22). The connecting disk (21) is connected to the load operating shaft (6), and the drive motor (22) is connected to the connecting disk (21) in a transmission connection.

9. The load switch according to claim 5, characterized in that, It also includes a grounding operation shaft (23), which and the disconnecting switch rotating shaft (4) are respectively located on opposite sides of the transfer drive shaft (3); A second actuating element (24) is fixedly connected to the grounding operation shaft (23), a third sliding column (25) is provided on the second rocker block (13), a second U-shaped groove (26) is provided on the second actuating element (24), and the third sliding column (25) passes through the second U-shaped groove (26).

10. A ring main unit, characterized in that, It includes a cabinet and a load switch as described in any one of claims 1 to 9, wherein the load switch is installed inside the cabinet.

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