Vacuum arc-extinguishing chamber

Abstract

The utility model provides a vacuum arc-extinguishing chamber, and belongs to the field of vacuum switches. The vacuum arc-extinguishing chamber comprises a movable end shell, a guide sleeve and a movable conducting rod, the guide sleeve is installed on the movable end shell, a guide matching body is directly fixed on the movable conducting rod or fixed on the movable conducting rod through a connecting piece, and the guide matching body is located on the inner side of the guide sleeve and is in guide fit with the guide sleeve in the axial direction. And the hardness of at least the matching surface of the guide matching body matched with the guide sleeve is higher than that of the movable conducting rod. According to the vacuum arc-extinguishing chamber, the guide matching body with high peripheral surface hardness is matched with the guide sleeve, compared with the prior art, the vacuum arc-extinguishing chamber has the advantages that the problem of clamping stagnation is not easy to occur in the use process, the reliability is higher, and an anti-torsion plane does not need to be processed on the movable conducting rod, so that the length of the movable conducting rod can be shortened.

Description

Technical Field

[0001] This utility model belongs to the field of vacuum switches, and in particular relates to a vacuum interrupter. Background Technology

[0002] Vacuum interrupters are core components of medium- and high-voltage switches. Their basic structure generally includes a housing, moving contact, stationary contact, moving conductive rod, stationary conductive rod, bellows, and guide sleeve. A moving end cover (i.e., moving end housing) is located at the axial end of the housing. The guide sleeve is mounted on the moving end cover and serves to guide the moving conductive rod axially. To prevent relative torsion between the guide sleeve and the moving conductive rod, anti-torsion planes parallel to their axes are also provided on the guide sleeve and the moving conductive rod. Examples of vacuum interrupters include those in Chinese invention patent application CN116092853A, Chinese utility model patent CN205194612U, and Chinese utility model patent CN219393257U.

[0003] The moving conductive rod is generally made of copper, a material with good electrical conductivity. Copper itself has relatively low hardness, and after the overall vacuum brazing of the vacuum interrupter, the moving conductive rod will be subjected to heat-affected zone conditions, further reducing its hardness. In conventional vacuum interrupters, this type of moving conductive rod directly mates with the guide sleeve. Due to the reduced hardness of the moving conductive rod, its surface is prone to localized deformation under stress during prolonged use, which can lead to jamming with the guide sleeve and affect normal operation.

[0004] Furthermore, the moving conductive rod is machined with an anti-torsion plane. The axial length of this anti-torsion plane is equal to the axial length of the guide sleeve plus the axial movement distance of the moving conductive rod. Therefore, the moving conductive rod needs to be long enough to machine the anti-torsion plane, which is not conducive to shortening the axial dimension of the moving conductive rod and reducing the overall height of the vacuum interrupter. Utility Model Content

[0005] The purpose of this utility model is to provide a vacuum interrupter to solve the technical problems in the prior art where the surface hardness of the moving conductive rod is low, which makes it easy for local surface deformation to occur during use, affecting the normal guiding and matching with the guide sleeve and causing jamming; and the technical problems that the moving conductive rod needs to be machined with an anti-torsion plane, resulting in a large length dimension, which is not conducive to the miniaturization of the vacuum interrupter.

[0006] To achieve the above objectives, the technical solution for the vacuum interrupter provided by this utility model is as follows:

[0007] A vacuum interrupter includes a moving end housing, a guide sleeve, and a moving conductive rod. The guide sleeve is mounted on the moving end housing. A guide mating body is directly fixed or fixed to the moving conductive rod via a connector. The guide mating body is located inside the guide sleeve and is axially guided and mated with the guide sleeve. The hardness of at least the mating surface of the guide mating body that mates with the guide sleeve is higher than the hardness of the moving conductive rod.

[0008] As a further improvement, the guide assembly is a guide cylinder, and a connection structure is provided between the guide cylinder and the moving conductive rod to fix the two together.

[0009] As a further improvement, the guide body is made of stainless steel.

[0010] As a further improvement, the moving conductive rod is provided with a moving contact at one end inside the vacuum interrupter housing. The vacuum interrupter includes a bellows coaxially sleeved on the moving conductive rod. The end of the bellows near the moving contact is fixedly connected to the moving end housing. The connection structure is located between the guide cylinder, the moving conductive rod, and the end of the bellows away from the moving contact and fixes the three together.

[0011] As a further improvement, the connection structure includes a first connecting ring and a second connecting ring arranged axially and fixedly connected to each other. The first connecting ring is connected between the bellows body and the guide cylinder, and the second connecting ring is connected between the moving conductive rod and the guide cylinder.

[0012] As a further improvement, the guide tube is nested on the outside of the bellows, with the end of the guide tube away from the moving contact connected to the connecting structure, and the end of the bellows away from the moving contact connected to the connecting structure.

[0013] As a further improvement, the moving end housing includes a connecting shell disposed inside the outer shell of the vacuum interrupter, with one end of the connecting shell near the moving contact connected to the end of the bellows near the moving contact, and the other end of the connecting shell away from the moving contact connected to the outer shell.

[0014] As a further improvement, the moving end housing includes a connecting shell and a mounting shell. The connecting shell is located inside the outer shell of the vacuum interrupter. The end of the connecting shell near the moving contact is connected to the end of the bellows near the moving contact, and the end of the connecting shell away from the moving contact is connected to the outer shell. The mounting shell is located outside the outer shell and is fixedly connected to the corresponding axial end of the outer shell or the connecting shell. The guide sleeve is disposed inside the mounting shell.

[0015] As a further improvement, the inner side of the mounting housing is provided with a limiting step for limiting the upper limit of the guide sleeve in the axial direction into the vacuum interrupter chamber, and a limiting member for limiting the upper limit of the guide sleeve in the axial direction out of the vacuum interrupter chamber is detachably installed on the inner side of the mounting housing.

[0016] As a further improvement, the moving conductive rod is provided with a moving contact at one end inside the vacuum interrupter housing. The vacuum interrupter includes a bellows coaxially sleeved on the moving conductive rod. The end of the bellows near the moving contact is fixedly connected to the moving end housing, and the end of the bellows away from the moving contact is directly fixedly connected to the moving conductive rod or fixedly connected to the moving conductive rod through an adapter.

[0017] The beneficial effects are as follows: The vacuum interrupter provided by this utility model is a pioneering utility model invention. This vacuum interrupter features a guide fitting on the moving conductive rod, which engages with the guide sleeve. The outer circumferential surface of the guide fitting has high hardness, thus avoiding jamming due to localized surface deformation during use, resulting in higher reliability. Furthermore, with the guide fitting, only the guide fitting needs to engage with the guide sleeve; there is no need to leave a long space on the moving conductive rod for machining an anti-torsion plane. Therefore, the length of the moving conductive rod can be shortened, which facilitates the overall miniaturization of the vacuum interrupter. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the vacuum interrupter in Embodiment 1 of this utility model;

[0019] Figure 2 This is a partial structural schematic diagram of Embodiment 1 of the vacuum interrupter in this utility model;

[0020] Figure 3 This is a schematic diagram of the vacuum interrupter in Embodiment 1 of this utility model, with the outer shell and stationary end shell removed.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Stationary end housing; 2. Stationary conductive rod; 3. Stationary contact; 4. Moving end housing; 41. Connecting shell; 42. Mounting shell; 43. Limiting step; 44. Mounting groove; 45. Connecting hole; 5. Moving conductive rod; 6. Moving contact; 7. Bellows; 8. Guide sleeve; 9. Main shielding cover; 10. Metallized ceramic shell; 11. End shielding cover; 12. Snap ring; 13. Guide cylinder; 14. First connecting ring; 15. Second connecting ring. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments.

[0024] To address the problems in the prior art, the basic concept of this utility model is to utilize a guide fitting with a high outer surface hardness to cooperate with the guide sleeve, thereby avoiding jamming problems. Moreover, it eliminates the need to process an anti-torsion plane on the moving conductive rod, which can shorten the length of the moving conductive rod.

[0025] Specific embodiment 1 of the vacuum interrupter provided by this utility model:

[0026] A vacuum interrupter, see appendix Figure 1 It includes an outer shell, a stationary end shell 1, a stationary conductive rod 2, a stationary contact 3, a moving end shell 4, a moving conductive rod 5, a moving contact 6, a bellows 7, and a guide sleeve 8.

[0027] The outer casing includes a main shield 9 located in the middle and metallized ceramic shells 10 fixed at both axial ends of the main shield 9. It also includes an end shield 11 fixed at the end of the metallized ceramic shell 10 away from the main shield 9. The stationary end shell 1 and the moving end shell 4 are respectively disposed at both axial ends of the outer casing. The stationary conductive rod 2 is fixedly disposed on the stationary end shell 1, and the stationary contact 3 is located at one end of the stationary conductive rod 2 inside the outer casing.

[0028] See appendix Figure 1 and in conjunction with the appendix Figure 2 and attached Figure 3 The moving conductive rod 5 passes axially through the moving end housing 4, and the moving contact 6 is installed at the end of the moving conductive rod 5 that extends into the housing. The axial movement of the moving conductive rod 5 can make the moving contact 6 contact and conduct with the stationary contact 3 or move the moving contact 6 away from the stationary contact 3, thereby realizing the closing or opening of the vacuum interrupter.

[0029] The bellows 7 is fitted onto the moving conductive rod 5 and maintains a certain radial distance from the moving conductive rod 5. The end of the bellows 7 near the moving contact 6 is fixedly connected to the moving end housing 4, and the end of the bellows 7 away from the moving contact 6 is fixedly connected to the moving conductive rod 5. Specifically, the moving end housing 4 includes a connecting housing 41 and a mounting housing 42. The main body of the connecting housing 41 is cylindrical and located inside the outer shell. The end of the main body of the connecting housing 41 facing the moving contact 6 has an inward flange, which is fixedly connected to the end of the bellows 7 near the moving contact 6. The end of the main body of the connecting housing 41 away from the moving contact 6 has an outward flange, which is fixedly connected to the axial end of the outer shell.

[0030] The mounting shell 42 is also a cylindrical structure, located outside the outer shell. One axial end of the mounting shell 42 is fixedly connected to the end face of the connecting shell 41 away from the moving contact 6. The guide sleeve 8 is disposed inside the mounting shell 42. The inner wall of the mounting shell 42 is provided with a limiting step 43 for upper limit of the guide sleeve 8 in the axial direction into the vacuum interrupter chamber. The guide sleeve 8 is provided with a mating step for axial stop engagement with the limiting step 43. In other embodiments, the guide sleeve 8 may not be provided with a mating step, but its axial end wall may directly engage with the mating step. A limiting member for upper limit of the guide sleeve 8 in the axial direction into the vacuum interrupter chamber is detachably installed inside the mounting shell 42. The limiting member is a retaining spring 12. The inner side of the mounting shell 42 is provided with an annular mounting groove 44 for mounting the retaining spring 12. The retaining spring 12 is located on the side of the limiting step 43 away from the moving contact 6 in the axial direction. During the assembly process, the guide sleeve 8 is first inserted into the mounting shell 42 along the axial direction, and then the snap ring 12 is assembled to fix the guide sleeve 8 axially. In this embodiment, the guide sleeve 8 is made of plastic, so it needs to be assembled after the entire vacuum interrupter is brazed.

[0031] The moving conductive rod is equipped with a guide fitting body, which is located inside the guide sleeve 8 and can guide and fit with the guide sleeve 8 axially. Specifically, the guide fitting body is a guide cylinder 13. A connecting structure is provided between the guide cylinder 13, the bellows 7, and the moving conductive rod 5 to fix the three together. The guide cylinder 13 and the bellows 7 are nested, with the guide cylinder 13 located outside the bellows 7. The end of the guide cylinder 13 furthest from the moving contact 6 is connected to the connecting structure, and the end of the bellows 7 furthest from the moving contact 6 is also connected to the connecting structure. The outer circumferential surface of the guide cylinder 13 is a mating surface that mates with the inner circumferential surface of the guide sleeve 8. The mating surface of the guide cylinder 13 has a large area, ensuring the stability of the guiding fit.

[0032] The connection structure specifically includes a first connecting ring 14 and a second connecting ring 15. The first connecting ring 14 connects the bellows 7 and the guide cylinder 13, and the second connecting ring 15 connects the movable conductive rod 5 and the guide cylinder 13. The first connecting ring 14 and the second connecting ring 15 are also fixedly connected axially via their end faces. In other embodiments, the first connecting ring 14 and the second connecting ring 15 may not be fixed to each other. In this embodiment, the second connecting ring 15 constitutes a connector for connecting the guide cylinder 13 and the movable conductive rod 5, and the second connecting ring 15 and the first connecting ring 14 together constitute an adapter for connecting the bellows 7 and the movable conductive rod 5.

[0033] In one embodiment of this invention, the fixing connection between each part is brazing. In other embodiments, the fixing connection between each part may be other forms of welding, or fasteners may be used if the requirements are met.

[0034] In this embodiment, the guide cylinder 13, the guide sleeve 8, and the mounting shell 42 are all provided with anti-torsion planes to prevent torsion. This is a conventional setting and will not be described in detail here.

[0035] In this embodiment, the guide cylinder 13, the bellows 7, the moving end housing 4 and the guide sleeve 8 form a closed space. Therefore, in order to facilitate the smooth movement of the moving conductive rod 5, a connecting hole 45 is provided on the side wall of the mounting shell 42 of the moving end housing 4 to connect the inner and outer sides of the moving end housing 4.

[0036] In this embodiment, the inner side of the bellows 7 is connected to the interior of the vacuum interrupter, which is a vacuum environment. The pressure on the outer side of the bellows 7 is higher than the pressure on the inner side. Therefore, the bellows 7 is subjected to external pressure and requires the use of a multi-layer bellows with higher strength. Multi-layer bellows are existing technology and will not be described in detail here.

[0037] The process of the moving contact 6 moving closer to the stationary contact 3 is the closing process of the vacuum interrupter, during which the bellows 7 is gradually compressed; the process of the moving contact 6 moving away from the stationary contact 3 is the opening process of the vacuum interrupter, during which the bellows 7 is gradually stretched. Therefore, when the moving contact 6 and the stationary contact 3 are in contact and conducting, the bellows 7 is in its shortest compressed state. At this time, the axial length of the part of the moving conductive rod 5 located inside the bellows 7 is relatively short, while the axial length of the part of the moving conductive rod 5 located inside the housing and outside the bellows 7 only needs to meet the set distance between the moving contact 6 and the bellows 7. Therefore, the total length of the moving conductive rod 5, including at least the above two parts, is shorter than the total length of the corresponding parts of the moving conductive rod 5 in the prior art. Thus, the overall size of the vacuum interrupter can be smaller than that of the prior art, which can meet the requirements for miniaturization of electrical equipment.

[0038] Moreover, since the moving conductive rod 5 in this embodiment no longer directly guides and cooperates with the guide sleeve 8, but instead guides and cooperates with the guide sleeve 8 through the guide cylinder 13, it is not necessary to process the anti-torsion plane on the moving conductive rod 5. Therefore, it is not necessary to reserve space for processing the anti-torsion plane on the conductive rod, which is conducive to reducing the axial dimension of the conductive rod, thereby further reducing the overall size of the vacuum interrupter.

[0039] The guide cylinder 13 can be made of a material with higher hardness to avoid jamming due to localized surface deformation during the guiding and mating process with the guide sleeve 8, and also to ensure the normal use of the moving conductive rod 5. Specifically, the guide cylinder 13 can be a machined stainless steel cylinder with high machining precision. It is less prone to deformation after high-temperature brazing and during the opening and closing process of the vacuum interrupter, and its wear resistance is better than that of the copper moving conductive rod 5, thus resulting in a longer service life. In other embodiments, the guide cylinder can also be made of other metallic or non-metallic materials, but the hardness of the mating surface of the guide cylinder with the guide sleeve must be higher than that of the moving conductive rod.

[0040] In the above embodiments of this invention, the guide cylinder and the bellows are nested, which can improve space utilization and shorten the overall size of the vacuum interrupter. In other embodiments, the guide cylinder and the bellows can also be arranged axially at intervals, in which case the end of the guide cylinder near the moving contact is connected to the end of the bellows away from the moving contact through a connecting structure.

[0041] In the above embodiments of this example, the guide cylinder, the bellows, and the moving conductive rod are connected by a connecting structure, which makes the structure more compact. In other embodiments, the connecting structure can be used only for the connection between the guide cylinder and the moving conductive rod, and the bellows can be connected to the moving conductive rod through other adapters; or in another embodiment, a convex ring structure can be machined on the moving conductive rod, and then the end of the bellows away from the moving contact can be directly welded and fixed to the convex ring structure.

[0042] Specific embodiment 2 of the vacuum interrupter provided by this utility model:

[0043] This embodiment is based on Embodiment 1. The difference between this embodiment and Embodiment 1 is that the guide cylinder and the bellows are arranged axially at intervals in this embodiment, and no connecting piece is provided between the guide cylinder and the conductive rod, but it is directly fixedly connected to the moving conductive rod.

[0044] Specific embodiment 3 of the vacuum interrupter provided by this utility model:

[0045] This embodiment is based on Embodiment 1. The difference between this embodiment and Embodiment 1 is that the guide fitting in this embodiment is a guide ring with an axial dimension smaller than that of the guide cylinder.

[0046] Specific embodiment 4 of the vacuum interrupter provided by this utility model:

[0047] This embodiment is based on Embodiment 1. The difference between this embodiment and Embodiment 1 is that the guide body in this embodiment is an arc-shaped slider arranged around the moving conductive rod.

[0048] Specific embodiment 5 of the vacuum interrupter provided by this utility model:

[0049] This embodiment is based on Embodiment 1. The difference between this embodiment and Embodiment 1 is that the bellows in this embodiment is an internally pressure-bearing bellows. The end of the bellows near the moving contact is fixedly connected to the moving conductive rod, and the end away from the moving contact is fixedly connected to the moving end housing. The guide sleeve is nested inside the bellows.

[0050] Finally, it should be noted that the above description is only a preferred embodiment of this utility model and is not intended to limit this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A vacuum interrupter, characterized in that, It includes a moving end housing, a guide sleeve, and a moving conductive rod. The guide sleeve is mounted on the moving end housing. A guide mating body is directly fixed to the moving conductive rod or fixed through a connector. The guide mating body is located inside the guide sleeve and guides the guide sleeve axially. The hardness of at least the mating surface of the guide mating body that mates with the guide sleeve is higher than the hardness of the moving conductive rod.

2. The vacuum interrupter according to claim 1, characterized in that, The guide assembly is a guide cylinder, and a connection structure is provided between the guide cylinder and the moving conductive rod to fix the two together.

3. The vacuum interrupter according to claim 1 or 2, characterized in that, The guide assembly is a stainless steel cylinder.

4. The vacuum interrupter according to claim 2, characterized in that, The moving conductive rod is located inside the outer shell of the vacuum interrupter and has a moving contact at one end. The vacuum interrupter includes a bellows coaxially sleeved on the moving conductive rod. The end of the bellows near the moving contact is fixedly connected to the moving end shell. The connection structure is located between the guide cylinder, the moving conductive rod and the end of the bellows away from the moving contact and fixes the three together.

5. The vacuum interrupter according to claim 4, characterized in that, The connection structure includes a first connecting ring and a second connecting ring arranged axially and fixedly connected to each other. The first connecting ring is connected between the bellows body and the guide cylinder, and the second connecting ring is connected between the moving conductive rod and the guide cylinder.

6. The vacuum interrupter according to claim 4, characterized in that, The guide tube is nested on the outside of the bellows. The end of the guide tube away from the moving contact is connected to the connecting structure, and the end of the bellows away from the moving contact is connected to the connecting structure.

7. The vacuum interrupter according to claim 4, characterized in that, The moving end housing includes a connecting shell disposed inside the outer shell of the vacuum interrupter. The end of the connecting shell near the moving contact is connected to the end of the bellows near the moving contact, and the end of the connecting shell away from the moving contact is connected to the outer shell.

8. The vacuum interrupter according to claim 4, characterized in that, The moving end housing includes a connecting shell and a mounting shell. The connecting shell is located inside the outer shell of the vacuum interrupter. The end of the connecting shell near the moving contact is connected to the end of the bellows near the moving contact, and the end of the connecting shell away from the moving contact is connected to the outer shell. The mounting shell is located outside the outer shell and is fixedly connected to the corresponding axial end of the outer shell or the connecting shell. The guide sleeve is located inside the mounting shell.

9. The vacuum interrupter according to claim 8, characterized in that, The inner side of the mounting housing is provided with a limiting step for limiting the upper limit of the guide sleeve in the axial direction into the vacuum interrupter chamber, and a limiting component for limiting the upper limit of the guide sleeve in the axial direction out of the vacuum interrupter chamber is detachably installed on the inner side of the mounting housing.

10. The vacuum interrupter according to claim 1 or 2, characterized in that, The moving conductive rod is located inside the outer shell of the vacuum interrupter and has a moving contact at one end. The vacuum interrupter includes a bellows coaxially sleeved on the moving conductive rod. The end of the bellows near the moving contact is fixedly connected to the moving end shell, and the end of the bellows away from the moving contact is directly fixedly connected to the moving conductive rod or fixedly connected to the moving conductive rod through an adapter.

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