An earthing switch and a solid insulation ring main switchgear using the same

Abstract

The present invention discloses a grounding switch, which comprises a moving contact and a static contact. The moving contact includes a support frame, on which a sliding member is provided. One end of a copper bar is connected to the support frame, and the other end of the copper bar is provided with two moving contact knife blades through a connecting pin. A spring is provided between each moving contact knife blade and the connecting pin, and the spring is sleeved on the connecting pin. The moving contact knife blade abuts against the other end of the copper bar under the action of the spring. When the support frame slides along the inner side wall of the solid-insulated ring main unit through the sliding member, the two moving contact knife blades can clamp the static contact or separate from the static contact. A flexible connection is also provided on the support frame. The present invention also discloses a solid-insulated ring main unit using the above-mentioned grounding switch. The purpose is to provide a grounding switch with a simple structure, low cost, and a surface contact is formed between the moving contact and the static contact to avoid overheating when the two are in contact, and a solid-insulated ring main unit using the same.

Description

Technical Field

[0001] The present invention relates to the technical field of ring main units, and particularly to an earthing switch and a solid-insulated ring main unit using the same. Background Art

[0002] A solid-insulated ring main unit is a set of electrical equipment (high-voltage switchgear) installed in a metal or non-metal insulated cabinet or made into a assembled sectionalized ring main power supply unit. Its core part adopts a load switch and a fuse, and has the advantages of simple structure, small volume, low price, improved power supply parameters and performance, and power supply safety. The solid-insulated ring main unit is widely used in distribution substations and box-type substations in load centers such as urban residential areas, high-rise buildings, large public buildings, and industrial enterprises. At present, the earthing switches of solid-insulated ring main units on the market generally adopt earthing switches composed of a plum blossom moving contact and a cylindrical static contact. Since it is difficult to make the convex platform inside the plum blossom contact into a flat structure, in most cases, such an earthing switch is in line contact when contacting, which is prone to overheating and causes equipment damage, resulting in the failure phenomenon during earthing. At the same time, the processing difficulty of the plum blossom moving contact is relatively large, and the cost is also relatively high. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an earthing switch with a simple structure, low cost, and a surface contact is formed between the moving contact and the static contact to avoid overheating when the two are in contact, and a solid-insulated ring main unit using the same.

[0004] The earthing switch in the present invention includes a moving contact and a static contact. The moving contact includes a support frame, and a sliding member for slidingly connecting with the inner side wall of the solid-insulated ring main unit is provided on the support frame. One end of a copper bar is connected to the support frame, and the other end of the copper bar is provided with two moving contact knife blades through a connecting pin. The two moving contact knife blades are respectively located on opposite sides of the other end of the copper bar. A spring is provided between each moving contact knife blade and the connecting pin. The spring is sleeved on the connecting pin. The moving contact knife blade abuts against the other end of the copper bar under the action of the spring. The static contact is in a plate shape and is arranged opposite to the two moving contact knife blades. When the support frame slides along the inner side wall of the solid-insulated ring main unit through the sliding member, the two moving contact knife blades can clamp the static contact or separate from the static contact. A flexible connection is also provided on the support frame.

[0005] The earthing switch in the present invention, wherein the support frame includes a support plate and a support rod. The support plate is a strip-shaped plate. A support rod is provided on one side of the support plate. The support rod is parallel to the support plate. One end of a copper rod is provided on the other side of the support plate. The copper rod is perpendicular to the support plate. One end of the copper rod, the support plate and the support rod are fixedly connected by bolts. A bearing rod is provided at each end of the support rod. A sliding member is provided on the bearing rod. A flexible connection is provided on the support plate.

[0006] The earthing switch in the present invention, wherein the sliding member is a sliding pin or a slider.

[0007] The earthing switch in the present invention, wherein the other end of the copper rod is flat. Two moving contact knife blades respectively abut against two flat sides of the other end of the copper rod. The two moving contact knife blades are respectively a first moving contact knife blade and a second moving contact knife blade. One end of the connecting pin is located on the side of the first moving contact knife blade away from the copper rod. The other end of the connecting pin sequentially passes through the first moving contact knife blade, the other end of the copper rod and the second moving contact knife blade. The other end of the connecting pin is located on the side of the second moving contact knife blade away from the copper rod. Springs are respectively sleeved on both ends of the connecting pin. The two springs are respectively a first spring and a second spring. The first spring is sleeved on one end of the connecting pin. One end of the first spring abuts against the first moving contact knife blade. The other end of the first spring abuts against one end of the connecting pin. The second spring is sleeved on the other end of the connecting pin. One end of the second spring abuts against the second moving contact knife blade. The other end of the second spring abuts against the other end of the connecting pin.

[0008] The earthing switch in the present invention, wherein a pin cap is provided at one end of the connecting pin. The other end of the first spring abuts against the pin cap at one end of the connecting pin. A radial protrusion is provided at the other end of the connecting pin. The other end of the second spring abuts against the radial protrusion at the other end of the connecting pin.

[0009] The earthing switch in the present invention, wherein a backing plate is provided between one end of the copper rod and the other side of the support plate. One end of the copper rod, the backing plate, the support plate and the support rod are fixedly connected by bolts.

[0010] The earthing switch in the present invention, wherein three copper rods and three static contacts are provided. The three static contacts are arranged in one-to-one correspondence with the three copper rods. The static contacts are arranged opposite to two moving contact knife blades on the corresponding copper rods.

[0011] The solid-insulated ring main unit in the present invention includes a cabinet body. A vacuum interrupter is provided inside the cabinet body. The above-mentioned earthing switch is also provided inside the cabinet body. A vertically arranged chute is provided on the inner side wall of the cabinet body. The sliding member is slidably connected in the chute. The other end of the copper bar is arranged downward. The static contact is located below the copper bar. The static contact is arranged on a wiring terminal. The wiring terminal is arranged on the cabinet body. Both ends of the wiring terminal are respectively located inside and outside the cabinet body. The static contact is communicated with both ends of the wiring terminal. The end of the wiring terminal located inside the cabinet body can be connected or disconnected from the static contact end of the vacuum interrupter. The end of the wiring terminal located outside the cabinet body is used to connect to an electrical device. The flexible connection is used for earthing.

[0012] In the solid-insulated ring main unit of the present invention, a driving structure is further provided on the cabinet body. The driving structure can drive the support frame to slide up and down along the chute through the sliding member.

[0013] The difference between the earthing switch in the present invention and the solid-insulated ring main unit using the same and the prior art is that the earthing switch in the present invention is a direct-acting earthing switch. The moving contact thereof is slidably connected vertically along the chute on the inner side wall of the ring main unit through the sliding member, and the static contact is arranged on the ring main unit through the wiring terminal. When earthing and closing, the end of the wiring terminal located inside the cabinet body is disconnected from the static contact end of the vacuum interrupter, and the moving contact slides downward until the two moving contact knife blades clamp the static contact, realizing earthing and closing. At this time, the static contact is located between the two moving contact knife blades. Since the static contact is plate-shaped, the two opposite flat side surfaces of the static contact are respectively in surface contact with the two moving contact knife blades. Under the action of the spring, the two moving contact knife blades can both abut against the copper bar and the static contact. At the same time, in order to achieve good contact between the moving and static contacts, the clamping force between the two moving contact knife blades can be adjusted through the spring, so that the two moving contact knife blades can clamp the copper bar and the static contact simultaneously. When earthing and opening, the moving contact slides upward until the two moving contact knife blades are separated from the static contact, realizing earthing and opening. It can be seen that the moving contact in the present invention is only composed of mechanical parts with a conventional shape, which is easy to process, has a simple structure and lower cost, and a surface contact can be formed between the moving contact and the static contact, thus avoiding overheating when the moving and static contacts are in contact.

[0014] The present invention will be further described below with reference to the accompanying drawings. Description of the Drawings

[0015] Figure 1 Structural schematic diagram when the earthing switch in the present invention is in earthing and closing Figure 1 ;

[0016] Figure 2 Structural schematic diagram when the earthing switch in the present invention is in earthing and closing Figure 2 ;

[0017] Figure 3 Structural schematic of the earthing switch in the present invention when it is in the earthed and open position Figure 1 ;

[0018] Figure 4 Structural schematic of the earthing switch in the present invention when it is in the earthed and open position Figure 2 ;

[0019] Figure 5 Structural schematic diagram of the static contact in the present invention;

[0020] Figure 6 Structural schematic of the moving contact in the present invention Figure 1 ;

[0021] Figure 7 Structural schematic of the moving contact in the present invention Figure 2 ;

[0022] Figure 8 Structural schematic of the moving contact in the present invention Figure 3 ;

[0023] Figure 9 Structural schematic of the moving contact in the present invention Figure 4 。 Detailed implementation manners

[0024] As Figure 1 shown, and in combination with Figures 2 - 9 shown, the earthing switch in the present invention includes a moving contact and a static contact 13. The moving contact includes a support frame. A sliding member for slidingly connecting with the inner side wall of the solid insulated ring main switchgear is provided on the support frame. One end of a copper bar 9 is connected to the support frame. The other end of the copper bar 9 is provided with two moving contact knife blades 10 through a connecting pin 11. The two moving contact knife blades 10 are respectively located on opposite sides of the other end of the copper bar 9. A spring 18 is provided between each moving contact knife blade 10 and the connecting pin 11. The spring 18 is sleeved on the connecting pin 11. The moving contact knife blade 10 abuts against the other end of the copper bar 9 under the action of the spring 18. The static contact 13 is in a plate shape and is arranged opposite to the two moving contact knife blades 10. When the support frame slides along the inner side wall of the solid insulated ring main switchgear through the sliding member, the two moving contact knife blades 10 can clamp the static contact 13 or separate from the static contact 13. A flexible connection 1 is also provided on the support frame.

[0025] The earthing switch in the present invention, wherein the support frame includes a support plate 3 and a support rod 4. The support plate 3 is a strip-shaped plate. A support rod 4 is provided on one side of the support plate 3. The support rod 4 is parallel to the support plate 3, and both the support rod 4 and the support plate 3 are arranged in the horizontal direction. One end of a copper rod 9 is provided on the other side of the support plate 3. The copper rod 9 is perpendicular to the support plate 3 and is arranged vertically. One end (i.e., the upper end) of the copper rod 9, the support plate 3 and the support rod 4 are fixedly connected by bolts 8, so that both the support rod 4 and the copper rod 9 are fixedly provided on the support plate 3 by bolts 8. Each end of the support rod 4 is provided with a bearing rod 6. The bearing rod 6 is arranged vertically, that is, the bearing rod 6 is perpendicular to the support rod 4. Two sliding members are provided on each bearing rod 6. The two sliding members on each bearing rod 6 are arranged at intervals along the length direction of the bearing rod 6. The sliding member is a sliding pin 7 or a slider.

[0026] As Figures 1 - 4 shown in FIGS. 6 - 9, a flexible connection 1 is provided on the support plate 3. The flexible connection 1, the support plate 3 and the support rod 4 are fixedly connected by bolts 2, so that the flexible connection 1 is fixedly provided on the support plate 3.

[0027] As Figures 1 - 4 shown in FIGS. 6 - 9, in the earthing switch of the present invention, the other end (i.e., the lower end) of the copper rod 9 is flat. Two moving contact knife blades 10 are respectively abutted against two flat sides of the other end of the copper rod 9, that is, one side of a moving contact knife blade 10 is abutted against one flat side of the lower end of the copper rod 9, and the other side of the other moving contact knife blade 10 is abutted against the other flat side of the lower end of the copper rod 9, so that the two moving contact knife blades 10 respectively achieve surface contact with the lower end of the copper rod 9. The two moving contact knife blades 10 are respectively a first moving contact knife blade and a second moving contact knife blade. One end of the connecting pin 11 is located on the side of the first moving contact knife blade away from the copper rod 9. The other end of the connecting pin 11 sequentially passes through the first moving contact knife blade, the other end of the copper rod 9 and the second moving contact knife blade. The other end of the connecting pin 11 is located on the side of the second moving contact knife blade away from the copper rod 9. In this way, the two moving contact knife blades 10 are provided on the other end of the copper rod 9 through the connecting pin 11 as described above. Springs 18 are respectively sleeved on both ends of the connecting pin 11. The two springs 18 are respectively a first spring and a second spring. The first spring is sleeved on one end of the connecting pin 11. One end of the first spring abuts against the first moving contact knife blade, and the other end of the first spring abuts against one end of the connecting pin 11. The second spring is sleeved on the other end of the connecting pin 11. One end of the second spring abuts against the second moving contact knife blade, and the other end of the second spring abuts against the other end of the connecting pin 11.

[0028] The earthing switch in the present invention, wherein one end of the connecting pin 11 is provided with a pin cap 16, the other end of the first spring abuts against the pin cap 16 at one end of the connecting pin 11, the other end of the connecting pin 11 is provided with a radial protrusion 17, and the other end of the second spring abuts against the radial protrusion 17 at the other end of the connecting pin 11. When installing the first spring and the second spring, a certain pre-tightening force is applied to the first spring and the second spring. In this way, when the first spring is sleeved on one end of the connecting pin 11, one end of the first spring abuts against the side of the first moving contact knife blade away from the copper bar 9, and the other end of the first spring abuts against the pin cap 16. Under the elastic force of the first spring, the side of the first moving contact knife blade close to the copper bar 9 abuts against a flat side at the lower end of the copper bar 9. Similarly, when the second spring is sleeved on the other end of the connecting pin 11, one end of the second spring abuts against the side of the second moving contact knife blade away from the copper bar 9, and the other end of the second spring abuts against the radial protrusion 17. Under the elastic force of the second spring, the side of the second moving contact knife blade close to the copper bar 9 abuts against another flat side at the lower end of the copper bar 9. In this way, the lower end of the copper bar 9 is clamped between the two moving contact knife blades 10.

[0029] As Figure 2 , 4 , 7, 9 show, in the earthing switch of the present invention, a spacer plate 5 is provided between one end (i.e., the upper end) of the copper bar 9 and another side of the support plate 3, and the one end of the copper bar 9, the spacer plate 5, the support plate 3 and the support rod 4 are fixedly connected by bolts 8.

[0030] As Figures 1 - 9 shows, in the earthing switch of the present invention, the copper bar 9 and the static contact 13 are both provided in three numbers. The three copper bars 9 are evenly spaced along the length direction of the support plate 3, and the three static contacts 13 are arranged in one-to-one correspondence with the three copper bars 9. The static contacts 13 are arranged opposite to the two moving contact knife blades 10 on the corresponding copper bars 9.

[0031] The solid insulated ring main switchgear in the present invention includes a cabinet body. A vacuum interrupter is provided in the cabinet body. The above-mentioned earthing switch is also provided in the cabinet body. A vertically arranged chute is provided on the inner side wall of the cabinet body. The sliding member is slidably connected in the chute. The other end of the copper bar 9 is arranged downward. The static contact 13 is located below the copper bar 9. The static contact 13 is provided on a wiring post 14. The wiring post 14 is provided on the cabinet body. Both ends of the wiring post 14 are located inside and outside the cabinet body respectively. The static contact 13 is communicated with both ends of the wiring post 14. The end 12 of the wiring post 14 located inside the cabinet body can be connected or disconnected from the static contact end of the vacuum interrupter. The end 15 of the wiring post 14 located outside the cabinet body is used to connect with an electrical device. The flexible connection 1 is used for earthing.

[0032] Inside the cabinet of the solid-insulated ring main unit, the moving contact and the static contact 13 in the earthing switch are arranged in the vertical direction, with the moving contact located above the static contact 13. The support frame of the moving contact is arranged in the horizontal direction, that is, both the support plate 3 and the support rod 4 of the support frame are arranged in the horizontal direction, and the copper bar 9 is arranged vertically. When the moving contact slides vertically along the inner side wall of the cabinet, the moving contact can contact or separate from the static contact 13. When the two are in contact, the moving contact clamps the static contact 13 to achieve earthing closing. On the contrary, when the two are separated, earthing opening is achieved.

[0033] In the solid-insulated ring main unit of the present invention, a driving structure is further provided on the cabinet body, and the driving structure can drive the support frame to slide up and down along the chute through the sliding member. There are various forms of the driving structure, and the more common ones are as follows: A rotating shaft is rotatably arranged on the cabinet body through a bearing, and a swing arm is fixedly arranged on the rotating shaft. The swing arm is located inside the cabinet body. One end of the swing arm is fixed on the rotating shaft, and the other end of the swing arm is movably connected to the upper end of the copper bar 9, that is, a long through hole is arranged along the length direction at the other end of the swing arm, and the upper end of the copper bar 9 is inserted through the pin shaft in the long through hole. In this way, when the rotating shaft is rotated, the swing arm rotates together with the rotating shaft, so the other end of the swing arm drives the support frame to slide up and down along the chute on the inner side wall of the cabinet body through the copper bar 9, that is, the entire moving contact slides up and down.

[0034] The earthing switch in the present invention is a direct-acting earthing switch. The moving contact is slidably connected to the inner side wall of the ring main unit in the vertical direction through a sliding member, and the static contact 13 is arranged on the ring main unit through a terminal post 14. When earthing closing, the inner end 12 of the terminal post 14 located inside the cabinet body is disconnected from the static contact end of the vacuum interrupter, and the moving contact slides downward until the two moving contact knife blades 10 clamp the static contact 13 to achieve earthing closing. At this time, the static contact 13 is located between the two moving contact knife blades 10. Since the static contact 13 is plate-shaped, the two opposite flat side surfaces of the static contact 13 are in surface contact with the two moving contact knife blades 10 respectively. Under the action of the spring 18, the two moving contact knife blades 10 can both abut against the copper bar 9 and the static contact 13. At the same time, in order to achieve good contact between the moving and static contacts, the clamping force between the two moving contact knife blades 10 can be adjusted through the spring 18, so that the two moving contact knife blades 10 can clamp the copper bar 9 and the static contact 13 at the same time. When earthing opening, the moving contact slides upward until the two moving contact knife blades 10 are separated from the static contact 13 to achieve earthing opening. It can be seen that the moving contact in the present invention is only composed of mechanical parts with a conventional shape, which is easy to process, has a simple structure, and lower cost. Moreover, a surface contact can be formed between the moving contact and the static contact 13, thus avoiding overheating when the moving and static contacts are in contact.

[0035] In addition, when connecting the electrical equipment to the power grid through the ring main unit, the earthing switch is in the earthed and open state. Connect the inner end 12 of the terminal post 14 inside the cabinet body to the static contact end of the vacuum interrupter, and then connect the moving and static contacts of the vacuum interrupter. After that, when disconnecting the electrical equipment from the power grid through the ring main unit, disconnect the moving and static contacts of the vacuum interrupter, and then disconnect the inner end 12 of the terminal post 14 inside the cabinet body from the static contact end of the vacuum interrupter. Thus, it can be seen that the connection and disconnection of the electrical equipment to / from the power grid are carried out in the earthed and open state, while the earthing closing operation is carried out in the state where the electrical equipment is disconnected from the power grid. When the earthing switch is in the earthed and closed state, the staff can maintain and repair the ring main unit to ensure the safety of the staff.

[0036] As Figure 5 shown, the terminal post 14 is a prior art, which includes a wire, the outside of the wire is coated with an insulating material, the two ends of the wire are respectively the two ends of the terminal post 14, and the static contact 13 is arranged on the terminal post 14 and the static contact 13 is connected to the wire, that is, the static contact 13 is in communication with both ends of the terminal post 14. The earthing switch is made of metal, for example, both the flexible connection 1 and the copper rod 9 are made of copper.

[0037] It should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "middle", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0038] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "connected" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0039] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An earthing switch, characterized in that: It includes a moving contact and a static contact. The moving contact includes a support frame. A sliding member for slidably connecting with the inner sidewall of the solid-insulated ring main unit is provided on the support frame. One end of a copper bar is connected to the support frame. The other end of the copper bar is provided with two moving contact knife blades through a connecting pin. The two moving contact knife blades are respectively located on opposite sides of the other end of the copper bar. A spring is provided between each moving contact knife blade and the connecting pin. The spring is sleeved on the connecting pin. The moving contact knife blade abuts against the other end of the copper bar under the action of the spring. The static contact is in a plate shape and is arranged opposite to the two moving contact knife blades. When the support frame slides along the inner sidewall of the solid-insulated ring main unit through the sliding member, the two moving contact knife blades can clamp the static contact or separate from the static contact. A flexible connection is also provided on the support frame. The support frame includes a support plate and a support rod. The support plate is a strip-shaped plate. A support rod is provided on one side surface of the support plate. The support rod is parallel to the support plate. One end of the copper bar is provided on the other side surface of the support plate. The copper bar is perpendicular to the support plate. One end of the copper bar, the support plate and the support rod are fixedly connected by bolts. A bearing rod is provided at each end of the support rod. The sliding member is provided on the bearing rod. The flexible connection is provided on the support plate. The sliding member is a sliding pin or a slider. A cushion plate is provided between one end of the copper bar and the other side surface of the support plate. One end of the copper bar, the cushion plate, the support plate and the support rod are fixedly connected by bolts.

2. The earthing switch according to claim 1, characterized in that: The other end of the copper bar is in a flat shape. The two moving contact knife blades respectively abut against the two flat side surfaces of the other end of the copper bar. The two moving contact knife blades are respectively a first moving contact knife blade and a second moving contact knife blade. One end of the connecting pin is located on the side of the first moving contact knife blade away from the copper bar. The other end of the connecting pin sequentially passes through the first moving contact knife blade, the other end of the copper bar and the second moving contact knife blade. The other end of the connecting pin is located on the side of the second moving contact knife blade away from the copper bar. The springs are respectively sleeved on the two ends of the connecting pin. The two springs are respectively a first spring and a second spring. The first spring is sleeved on one end of the connecting pin. One end of the first spring abuts against the first moving contact knife blade. The other end of the first spring abuts against one end of the connecting pin. The second spring is sleeved on the other end of the connecting pin. One end of the second spring abuts against the second moving contact knife blade. The other end of the second spring abuts against the other end of the connecting pin.

3. The earthing switch according to claim 2, wherein: A pin cap is provided at one end of the connecting pin. The other end of the first spring abuts against the pin cap at one end of the connecting pin. A radial protrusion is provided at the other end of the connecting pin. The other end of the second spring abuts against the radial protrusion at the other end of the connecting pin.

4. The earthing switch according to claim 3, characterized in that: Both the copper bar and the static contact are provided in three. The three static contacts are arranged in one-to-one correspondence with the three copper bars. The static contact is arranged opposite to the two moving contact knife blades on the corresponding copper bar.

5. A solid-insulated ring main unit, comprising a cabinet body, wherein a vacuum interrupter is arranged inside the cabinet body, and it is characterized in that: The cabinet further comprises an earthing switch as described in any one of claims 1-4. A vertically arranged chute is provided on the inner side wall of the cabinet. The sliding member is slidably connected in the chute. The other end of the copper bar is arranged downward. The static contact is located below the copper bar. The static contact is provided on a wiring terminal. The wiring terminal is provided on the cabinet. Both ends of the wiring terminal are respectively located inside and outside the cabinet. The static contact is communicated with both ends of the wiring terminal. The end of the wiring terminal located inside the cabinet can be connected or disconnected from the static contact end of the vacuum interrupter. The end of the wiring terminal located outside the cabinet is used to connect to an electrical device. The flexible connection is used for earthing.

6. The solid-insulated ring main unit according to claim 5, characterized in that: A driving structure is further provided on the cabinet. The driving structure can drive the support frame to slide up and down along the chute through the sliding member.

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