Vacuum arc-extinguishing chamber for load break switch

Abstract

The utility model discloses a kind of vacuum arc-extinguishing chambers for load switch, including ceramic shell, the ceramic shell top is fixedly connected with connecting cylinder, the connecting cylinder outer wall is threadedly connected with movable end cover body, movable end cover body is internally provided with movable port, movable port is movably connected with movable end assembly, the bottom surface of movable port is fixedly connected with sealing baffle, and the top of the sealing baffle and movable end assembly top surface contact, first sealing ring is arranged at the joint of movable port and sealing baffle, the middle part of movable port inner wall surface is provided with second sealing ring, the surface of first sealing ring and second sealing ring and movable end assembly contact, the third sealing ring is arranged at the joint of connecting cylinder and ceramic shell, and the surface of third sealing ring and movable end cover body bottom surface contact.By movable end cover body and ceramic shell are connected by thread, cooperate triple sealing ring to realize reliable sealing, movable end cover body can be directly disassembled and replaced locally, reduce use cost.

Description

Technical Field

[0001] This utility model relates to the field of vacuum interrupter technology, specifically a vacuum interrupter for load switches. Background Technology

[0002] Vacuum interrupters, also known as vacuum switch tubes, are core components of medium and high voltage power switches. Their main function is to quickly extinguish the arc and suppress the current after the medium and high voltage circuit is cut off by utilizing the excellent insulation of the vacuum inside the tube, thus preventing accidents and unexpected events. They are mainly used in power transmission and distribution control systems, and also in power distribution systems in metallurgy, mining, petroleum, chemical, railway, broadcasting, communications, and industrial high-frequency heating.

[0003] However, the vacuum interrupters used in existing load switches are designed with a one-piece molded structure to increase their sealing performance. When the vacuum interrupter is used in a high-current environment, its service life is greatly reduced, making it impossible to replace internal components and thus increasing the cost of use. Summary of the Invention

[0004] The purpose of this utility model is to provide a vacuum interrupter for load switches, in order to solve the problem mentioned in the background art that the vacuum interrupters used in existing load switches adopt an integral molding structure design to increase their sealing performance. However, when the vacuum interrupter is used in a high current environment, its service life is greatly reduced, making it impossible to replace internal components and thus increasing the cost of use.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a vacuum interrupter for a load switch, comprising a ceramic housing, a connecting cylinder fixedly connected to the top of the ceramic housing, a moving end cover threadedly connected to the outer wall of the connecting cylinder, a movable opening provided inside the moving end cover, a moving end assembly movably connected inside the movable opening, a sealing baffle fixedly connected to the bottom surface of the movable opening, the top of the sealing baffle contacting the top surface of the moving end assembly, a first sealing ring provided at the connection between the movable opening and the sealing baffle, a second sealing ring provided in the middle of the inner wall surface of the movable opening, the first and second sealing rings contacting the surface of the moving end assembly, and a third sealing ring provided at the connection between the connecting cylinder and the ceramic housing, the surface of the third sealing ring contacting the bottom surface of the moving end cover.

[0006] Preferably, a cavity is formed inside the ceramic housing, a stationary end assembly is installed at the bottom of the ceramic housing, and the stationary end assembly passes through the ceramic housing and makes movable contact with the moving end assembly. A shielding cylinder is installed inside the cavity at the relative contact position between the stationary end assembly and the moving end assembly.

[0007] Preferably, the moving end assembly includes a moving conductive rod, a moving contact, a bellows, and a moving conductive block. The moving conductive rod moves between the moving opening and the cavity. The moving contact is fixedly connected to the bottom of the moving conductive rod. The surface of the moving conductive rod is sleeved on the bellows, and the bellows is disposed in the moving end cover body. The moving conductive block is fixedly connected to the top of the moving conductive rod, and the surface of the moving conductive block is in contact with the surfaces of the first sealing ring and the second sealing ring.

[0008] Preferably, the stationary end assembly includes a stationary conductive block, a stationary conductive rod, and a stationary contact. The stationary conductive block is fixedly installed at the bottom of the ceramic housing, and a stationary conductive rod is fixedly installed on the top of the stationary conductive block. The stationary conductive rod passes through the ceramic housing and is fixedly connected to the stationary contact.

[0009] Preferably, the moving contact is movably connected to the stationary contact.

[0010] Beneficial effects

[0011] Compared with existing technologies, the beneficial effects of this utility model are as follows:

[0012] The vacuum interrupter for load switches of this invention is connected to the ceramic housing by a threaded connection between the moving end cover and the ceramic housing, and is equipped with a triple sealing ring to achieve a reliable seal. This solves the problems of difficult maintenance and short lifespan of traditional one-piece molded interrupters. When there is a large current loss, the moving end cover can be directly disassembled for partial replacement without scrapping the entire interrupter, which significantly reduces the cost of use. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0014] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0015] Figure 3 This is an enlarged structural diagram of point A in this utility model;

[0016] Figure 4 This is an enlarged structural diagram of section B of this utility model.

[0017] The correspondence between the labels and component names in the attached figures is as follows:

[0018] 1. Ceramic housing; 2. Moving end cover; 3. Moving end assembly; 4. Stationary end assembly; 5. Shielding cylinder;

[0019] 11. Chamber; 12. Connecting cylinder; 13. Third sealing ring; 21. Movable port; 22. Sealing baffle;

[0020] 23. First sealing ring; 24. Second sealing ring; 31. Moving conductive rod; 32. Moving contact; 33. Bellows;

[0021] 34. Moving conductive block; 41. Stationary contact; 42. Conductive rod; 43. Stationary conductive block. Detailed Implementation

[0022] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] In the description of this utility model, it should be noted that the terms "upper," "lower," "left," "right," "front," "rear," "inner," "outer," "vertical," and "horizontal," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] like Figures 1-4 This is a schematic diagram of a vacuum interrupter for a load switch according to a preferred embodiment of the present invention. In this embodiment, the vacuum interrupter for a load switch includes a ceramic shell 1, which forms the main body of the interrupter and creates a high-vacuum chamber 11 inside. A metal connecting cylinder 12 is fixedly connected to the top of the ceramic shell 1 by welding or high-temperature sintering. An annular third sealing ring 13 is embedded at the junction of the connecting cylinder 12 and the ceramic shell 1 to achieve a static vacuum seal at the connection. The external thread of the connecting cylinder 12 engages with the internal thread of the moving end cover 2. The bottom end face of the moving end cover 2 is pressed against the surface of the third sealing ring 13, forming a reliable axial seal.

[0025] In this embodiment, a through-hole 21 is provided at the center of the moving end cover 2, and the moving end assembly 3 is axially slidably installed within the through-hole 21. The moving end assembly 3 includes a moving conductive rod 31, a moving contact 32, and a bellows 33. The moving conductive rod 31 axially penetrates the through-hole 21 and extends into the chamber 11; the moving contact 32 is fixedly connected to the bottom end of the moving conductive rod 31 that extends into the chamber 11; the bellows 33 is sleeved on the moving conductive rod 31, with its lower end fixed to a support structure inside the moving end cover 2 and its upper end fixed to the moving conductive rod 31. The bellows 33 is located below the through-hole 21, and its function is to allow the moving conductive rod 31 to move axially while maintaining the vacuum seal of the chamber 11. The moving conductive block 34 is fixedly connected to the top of the moving conductive rod 31 located at the through-hole 21.

[0026] In this embodiment, an annular sealing baffle 22 is fixedly connected to the bottom end of the movable port 21 facing the chamber 11. The top end face of the sealing baffle 22 is in contact with or has a very small gap fit with the bottom end face of the moving conductive block 34, thereby forming a first axial sealing barrier. A first sealing ring 23 is provided at the junction of the sealing baffle 22 and the inner wall of the movable port 21. The first sealing ring 23 is in close contact with the side surface of the moving conductive block 34, forming a radial seal. At the same time, a second sealing ring 24 is embedded in the middle of the inner wall surface of the movable port 21, above the sealing baffle 22. The second sealing ring 24 is also in close contact with the side surface of the moving conductive block 34, forming a second radial seal. The first sealing ring 23 and the second sealing ring 24 work together to effectively prevent external ambient gas from entering along the gap between the moving conductive rod 31 and the movable port 21, ensuring a long-term vacuum inside the vacuum interrupter. The side surface of the moving conductive block 34 is the main contact surface of these two sealing rings.

[0027] In this embodiment, the stationary end assembly 4 includes a stationary conductive block 43, a stationary conductive rod 42, and a stationary contact 41. The stationary conductive block 43 is fixedly installed on the bottom outer side of the ceramic housing 1 by welding. One end of the stationary conductive rod 42 is fixedly connected to the top of the stationary conductive block 43, and the other end extends upward through the bottom sealing part of the ceramic housing 1 and into the cavity 11 to be fixedly connected to the stationary contact 41.

[0028] In this embodiment, the moving contact 32 and the stationary contact 41 are arranged opposite to each other. When the moving end assembly 3 moves downward under the drive of the operating mechanism, the moving contact 32 and the stationary contact 41 close to form a conductive path; when it moves upward, the contacts separate and the arc is extinguished in the high vacuum chamber 11.

[0029] In this embodiment, a metal shielding cylinder 5 is fixedly installed inside the chamber 11, located around the contact area between the moving contact 32 and the stationary contact 41. The main function of the shielding cylinder 5 is to improve the electric field distribution inside the chamber 11, adsorb metal vapor particles generated during the switching process, protect the inner wall of the ceramic shell 1 from contamination, and maintain insulation strength and vacuum level.

[0030] Working principle:

[0031] When the load switch needs to be closed, the external operating mechanism drives the moving end assembly 3 to move downward through the moving conductive rod 31 to overcome the elastic force of the bellows 33, causing the moving contact 32 to make close contact with the stationary contact 41, and the current forms a circuit through the stationary conductive block 43>stationary conductive rod 42>stationary contact 41>moving contact 32>moving conductive rod 31>moving conductive block 34.

[0032] When the load switch needs to be tripped, the operating mechanism releases or reverses the upward movement of the moving end assembly 3. The moving contact 32 separates from the stationary contact 41, generating an electric arc between them. In the high-vacuum chamber 11, the arc is rapidly cooled and diffused, the metal vapor is adsorbed by the shielding cylinder 5, and the current is forcibly extinguished at the zero-crossing point. The bellows 33 undergoes elastic deformation as the moving conductive rod 31 moves, maintaining the vacuum seal of the chamber 11 at all times. The double radial seals of the first and second sealing rings 23 and 24 within the movable port 21, the axial seal of the sealing baffle 22, and the third sealing ring 13 at the connecting cylinder 12 together ensure the long-term reliable vacuum seal of the entire arc-extinguishing chamber, especially the moving end sliding part.

[0033] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present utility model. It should not be construed that the specific implementation of the present utility model is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present utility model, and all such deductions or substitutions should be considered to fall within the scope of protection defined by the claims submitted by the present utility model.

Claims

1. A vacuum interrupter for a load switch, comprising a ceramic housing (1), characterized in that: A connecting cylinder (12) is fixedly connected to the top of the ceramic shell (1). A movable end cover (2) is threadedly connected to the outer wall of the connecting cylinder (12). A movable opening (21) is provided inside the movable end cover (2). A movable end assembly (3) is movably connected inside the movable opening (21). A sealing baffle (22) is fixedly connected to the bottom surface of the movable opening (21). The top of the sealing baffle (22) is in contact with the top surface of the movable end assembly (3). A first sealing ring (23) is provided at the connection between the movable opening (21) and the sealing baffle (22). A second sealing ring (24) is provided in the middle of the inner wall surface of the movable opening (21). The first sealing ring (23) and the second sealing ring (24) are in contact with the surface of the movable end assembly (3). A third sealing ring (13) is provided at the connection between the connecting cylinder (12) and the ceramic shell (1). The surface of the third sealing ring (13) is in contact with the bottom surface of the movable end cover (2).

2. The vacuum interrupter for a load switch according to claim 1, characterized in that: A cavity (11) is provided inside the ceramic shell (1). A stationary end assembly (4) is installed at the bottom of the ceramic shell (1), and the stationary end assembly (4) passes through the ceramic shell (1) and is in contact with the moving end assembly (3). A shielding cylinder (5) is installed in the cavity (11) at the relative position of the contact between the stationary end assembly (4) and the moving end assembly (3).

3. The vacuum interrupter for a load switch according to claim 2, characterized in that: The moving end assembly (3) includes a moving conductive rod (31), a moving contact (32), a bellows (33), and a moving conductive block (34). The moving conductive rod (31) moves within the moving port (21) and the chamber (11). The moving contact (32) is fixedly connected to the bottom of the moving conductive rod (31). The surface of the moving conductive rod (31) is sleeved on the bellows (33), and the bellows (33) is located inside the moving end cover (2). The moving conductive block (34) is fixedly connected to the top of the moving conductive rod (31), and the surface of the moving conductive block (34) is in contact with the surfaces of the first sealing ring (23) and the second sealing ring (24).

4. The vacuum interrupter for a load switch according to claim 2, characterized in that: The stationary end assembly (4) includes a stationary conductive block (43), a stationary conductive rod (42), and a stationary contact (41). The stationary conductive block (43) is fixedly installed at the bottom of the ceramic housing (1). The stationary conductive rod (42) is fixedly installed at the top of the stationary conductive block (43). The stationary conductive rod (42) passes through the ceramic housing (1) and is fixedly connected to the stationary contact (41).

5. The vacuum interrupter for a load switch according to claim 3, characterized in that: The moving contact (32) is movably connected to the stationary contact (41).

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