Bearing structure for movable side electrification shaft, vacuum interrupter, and manufacturing method of vacuum interrupter

Abstract

To provide a technique capable of contributing to productivity improvement, etc., by preventing a bearing from being desorbed from a flange penetration ole even without using an adhesive agent, a bolt, etc.SOLUTION: A bearing 4 is applied which is configured by including a flange-shaped part 5, which is an annular shape of a larger diameter than an opening diameter in a flange penetration hole 3 at the other side in a shaft center direction, and a cylindrical wall part 6 extending from an inner peripheral edge of the flange-shaped part 5 in the shaft center direction. In the cylindrical wall part 6, a claw portion 61 is formed on an outer peripheral surface 6b and an outer diameter in a location, where the claw portion 61 is formed, is larger than an opening diameter in the flange penetration hole 3 at one side in the shaft center direction. In the cylindrical wall part 6, a plurality of slit holes in a shape extending in the shaft center direction while penetrating in a radial direction and in a shape opened at one side in the shaft center direction is formed while being spaced at a predetermined interval in a circumferential direction and each cylindrical wall part piece, which is a portion between the slit holes, is elastically freely deformable in the radial direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a bearing structure of a movable-side energizing shaft, a vacuum interrupter, and a method for manufacturing a vacuum interrupter, and relates to a technology applicable to, for example, various power facilities and the like.

Background Art

[0002] As an example of a vacuum interrupter applied to, for example, various power facilities and the like, there is one in which one side (fixed side) and the other side (movable side) in the axial direction of an insulating cylindrical main body (hereinafter, simply referred to as the axial direction as appropriate) are sealed with a fixed-side flange and a movable-side flange, respectively, to form a vacuum vessel. Inside this vacuum vessel, both a fixed electrode and a movable electrode are arranged so as to face each other in the axial direction.

[0003] Inside the fixed-side flange of the vacuum vessel, a fixed-side energizing shaft is provided so as to extend in the axial direction from the inside of the vacuum vessel, and a fixed electrode is supported at the end of the fixed-side energizing shaft.

[0004] In the movable-side flange, a flange through-hole penetrating the movable-side flange in the axial direction is provided, and a bearing for guiding the movable-side energizing shaft in the axial direction (for example, guiding in a non-rotatable state) is provided in the flange through-hole. The movable-side energizing shaft is supported inside the vacuum vessel of the movable-side flange via a bellows that is axially telescopic.

[0005] According to the vacuum interrupter configured as described above, while maintaining the vacuum state inside the vacuum vessel (specifically, the outer peripheral side of the bellows inside the vacuum vessel), the movable-side energizing shaft (and the movable electrode) can be moved while being guided in the axial direction, and the movable electrode can be brought into contact with and separated from the fixed electrode (the contact is opened and closed) according to the movement of the movable-side energizing shaft.

[0006] When moving the movable-side energized shaft in the axial direction, if a frictional force is generated between the movable-side energized shaft and the bearing, there is a risk that the bearing may slip out of the flange through-hole and become detached (fall off) due to the frictional force. In such a case, for example, as shown in Patent Document 1, it is possible to suppress the bearing from detaching from the flange through-hole by adhering the bearing to the movable-side flange using an adhesive.

[0007] Also, if the movable-side energized shaft rotates, there is a risk that the rotational force will be applied to the bellows or the like, causing damage or the like. In such a case, in the bearing, it is possible to configure it so that the movable-side energized shaft can be guided in the axial direction in a non-rotatable state (for example, in Patent Document 2, in the insertion guide (reference numeral 11), a contact surface (reference numeral 12) corresponding to the two-sided width is formed).

[0008] In addition, in the cylindrical wall portion (guide hole) of the bearing through which the movable-side energized shaft is inserted, a configuration (for example, the configuration shown in Patent Document 3) is also known in which the diameter of the opening side is increased to allow a certain degree of radial swing of the movable-side energized shaft.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0010] To adhere the bearing to the movable-side flange using an adhesive, for example, it is possible to dry and solidify the adhesive in a state where the adhesive is interposed between the bearing and the movable-side flange. However, since a certain amount of time is required to reach the solidified state, there is a risk of causing a decrease in productivity or the like.

[0011] In addition, since many adhesives are flammable, the heat-resistant temperature of the vacuum interrupter may be lowered. In this case, there is also a risk that the use of the vacuum interrupter will be restricted (for example, restricted so that the location where the adhesive is interposed does not become hot).

[0012] Note that it is also conceivable to use bolts or the like instead of the adhesive to fasten and fix the bearing to the movable-side flange. In this case, however, there is a risk of increasing the assembly man-hours, complicating the structure, increasing the size, and increasing the cost.

[0013] Therefore, it is desirable to suppress the bearing from detaching from the flange through-hole without using an adhesive, bolts, or the like.

[0014] The present invention has been made in view of such technical problems, and an object thereof is to provide a technology that can suppress the bearing from detaching from the flange through-hole without using an adhesive, bolts, or the like and can contribute to improvement in productivity and the like.

Means for Solving the Problems

[0015] The bearing structure of the movable-side energizing shaft, the vacuum interrupter, and the method for manufacturing the vacuum interrupter according to this invention can contribute to the solution of the above problems.

[0016] First, one aspect of the bearing structure of the movable-side energizing shaft is a bearing structure of the movable-side energizing shaft that supports the movable electrode so as to be movable in the axial direction, among the fixed electrode and the movable electrode provided to face each other in the axial direction of the cylindrical body in a vacuum vessel having an insulating cylindrical main body.

[0017] The cylindrical body has a fixed side, which is one side in the axial direction, sealed by a fixed-side flange, and a movable side, which is the other side in the axial direction, sealed by a movable-side flange. The movable-side flange is provided with a flange through-hole that penetrates the movable-side flange in the axial direction. The movable-side current-carrying shaft is inserted through the flange through-hole and extends in the axial direction. One side of the movable-side current-carrying shaft is supported inside the vacuum vessel of the movable-side flange via a bellows that is axially telescopic. The flange through-hole is provided with a bearing that guides the movable-side current-carrying shaft in the axial direction in a non-rotatable state with respect to the flange through-hole.

[0018] The bearing is an annular shape with a diameter larger than the opening diameter of the opening on the other side of the flange through-hole, and has a flange-shaped portion extending along the opening edge surface of the opening on the other side. The bearing also has a cylindrical wall portion extending from the inner peripheral edge portion of the flange-shaped portion to the one side, inserted into the flange through-hole from the other side to the one side, and guiding the movable-side current-carrying shaft inserted into the inner peripheral surface side of the cylindrical wall portion in the axial direction.

[0019] The cylindrical wall portion has claw portions protruding radially outward on the outer peripheral surface of the cylindrical wall portion. A plurality of slit holes are formed at predetermined intervals in the circumferential direction of the cylindrical wall portion, with a shape that penetrates the cylindrical wall portion in the radial direction and extends in the axial direction and an opening on the one side. Each cylindrical wall portion piece, which is a portion between each of the slit holes in the circumferential direction of the cylindrical wall portion, is elastically deformable in the radial direction. The outer diameter of the portion of the cylindrical wall portion where the claw portions are formed is larger than the opening diameter of the opening on the one side of the flange through-hole.

[0020] When the dimension between the flange-shaped portion and the claw portions is L and the dimension in the axial direction of the flange through-hole is T, it is characterized by satisfying the following formula (1). L≧T ……(1).

[0021] Also, when the dimensional tolerance of the diameter of the flange through-hole is Δφ, the dimension in the protruding direction in the claw portion is t1, the clearance dimension between both the cylindrical wall portion and the movable-side energization shaft is C, the dimensional tolerance related to T is ΔT, and the dimension of the clearance provided between both the opening edge surface of the one-side opening and the claw portion is α, it may be characterized by satisfying the following formulas (2) and (3). Δφ < t1 < C ……(2) L = T + ΔT + α ……(3).

[0022] Also, the claw portion has a shape protruding outward in the radial direction as it approaches from the one side to the other side, and the surface on the other side of the claw portion is formed flat along the opening edge surface of the one-side opening in the flange through-hole, which may be characterized by this.

[0023] Also, at least one recess is formed on the opening edge surface of the other-side opening, and a convex portion that can be fitted into the recess is formed at a position facing the recess in the flange-shaped portion, which may be characterized by this.

[0024] Also, the recesses are formed in a plurality at a predetermined interval in the circumferential direction with respect to the opening edge surface of the other-side opening, and are formed to be rotationally symmetric on the opening edge surface when the axial direction is the axis of symmetry, which may be characterized by this.

[0025] Also, the convex portion may be formed on the base portion side of the cylindrical wall portion piece in the flange-shaped portion, which may be characterized by this.

[0026] Also, when the dimensional tolerance related to T is ΔT, the dimension of the clearance provided between both the opening edge surface of the one-side opening and the claw portion is α, and the dimension in the protruding direction of the convex portion is t2, it may be characterized by satisfying the following formula (4). t2 > ΔT + α ……(4).

[0027] One aspect of the vacuum interrupter is characterized by having a bearing structure for the movable-side energizing shaft as described above.

[0028] One aspect of the method for manufacturing a vacuum interrupter includes a vacuum brazing step of inserting a movable-side energizing shaft through a flange through-hole and extending it in the axial direction, and then brazing the one side of the movable-side energizing shaft inside the vacuum vessel of the movable-side flange via the bellows; and a bearing engagement step of, after the vacuum brazing step, fitting the bearing from the other side of the movable-side energizing shaft and providing it in the flange through-hole.

Advantages of the Invention

[0029] As described above, according to the present invention, it is possible to suppress the bearing from detaching from the flange through-hole without using an adhesive, bolts, etc., and it can contribute to improving productivity and the like.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0031] The bearing structure of the movable-side energizing shaft, the vacuum interrupter, and the manufacturing method of the vacuum interrupter according to the embodiment of the present invention are completely different from a configuration in which a bearing is simply adhered to a movable-side flange using an adhesive (hereinafter, simply referred to as a conventional configuration as appropriate).

[0032] That is, this embodiment is a configuration in which a bearing that can be inserted through the flange through-hole with elastic deformation (engageable with a so-called snap-fit structure) is applied.

[0033] Specifically, a bearing having a flange-shaped portion that is annular and has a larger diameter than the opening diameter of the opening on the other side (movable side) in the axial direction of the flange through-hole, and a cylindrical wall portion extending in the axial direction from the inner peripheral edge portion of the flange-shaped portion is applied.

[0034] On the outer peripheral surface of the cylindrical wall portion of this bearing, a claw portion having a shape protruding outward in the radial direction of the cylindrical wall portion is formed, and the outer diameter of the portion where the claw portion is formed is made larger than the opening diameter of the opening on one side (fixed side) in the axial direction of the flange through-hole.

[0035] Further, in the cylindrical wall portion, a plurality of slit holes having a shape penetrating in the radial direction (hereinafter, simply referred to as the radial direction as appropriate) of the cylindrical wall portion and extending in the axial direction and having an opening on one side in the axial direction are formed at predetermined intervals in the circumferential direction (hereinafter, simply referred to as the circumferential direction as appropriate) of the cylindrical wall portion. Thereby, each cylindrical wall portion piece, which is a portion between the respective slit holes in the cylindrical wall portion, is made elastically deformable in the radial direction.

[0036] Further, when the dimension between both the flange-shaped portion and the claw portion is L and the dimension in the axial direction of the flange through-hole is T, it is assumed that the following formula (1) is satisfied.

[0037] L ≧ T ……(1) When such a cylindrical wall portion of the bearing is inserted from the other side in the axial direction toward the one side in the axial direction with respect to the flange through-hole, while the claw portion of the cylindrical wall portion is positioned within the flange through-hole, the cylindrical wall portion piece will elastically deform inward in the radial direction. Then, after the claw portion of the cylindrical wall portion disengages from the inside of the flange through-hole toward the one side in the axial direction, the cylindrical wall portion piece elastically returns. As a result, the bearing engages with the flange through-hole in a posture where the movable-side flange (the hole wall of the flange through-hole) is sandwiched in the axial direction by both the flange-shaped portion and the claw portion.

[0038] For a bearing engaged with the flange through-hole in this way, detachment from the flange through-hole is suppressed (the engaged state is maintained) without using an adhesive, bolts, etc. Also, since an adhesive is not required, for example, a situation where the use of a vacuum interrupter is restricted as in the conventional configuration can be suppressed.

[0039] To make the inside of the vacuum vessel a vacuum state, assembling the respective components (for example, the cylindrical main body, the fixed-side flange, the movable-side flange, the bellows, the movable-side current-carrying shaft, etc.) that form the vacuum state by a vacuum brazing process can be mentioned.

[0040] However, in the vacuum brazing process, since the brazing material arranged at the assembling location is heated and melted, in a state where there is a combustible adhesive as in the conventional configuration, there is a possibility that the vacuum brazing process will be hindered (or become impossible). Therefore, when using an adhesive, after performing the above-described vacuum brazing process in a state where the movable-side current-carrying shaft is inserted through the flange through-hole and extended in the axial direction in advance, the bearing is fitted from the other side in the axial direction of the movable-side current-carrying shaft and adhered to the movable-side flange.

[0041] On the other hand, the bearing according to the present embodiment may be provided in a manner that allows it to be inserted through the flange through-hole with elastic deformation, and it can be easily configured using various materials. For this reason, for example, when the bearing of the present embodiment is made of a resin material, if the heat-resistant temperature of the resin material is higher than the vacuum brazing temperature, the bearing may be engaged with the flange through-hole in advance in the pre-step of the vacuum brazing process as described above.

[0042] In addition, each component after the vacuum brazing process as described above may undergo thermal expansion depending on the material and shape. For example, when the movable-side flange undergoes thermal expansion, dimensional tolerances may occur in the axial dimension (T) and the hole diameter of the flange through-hole.

[0043] The bearing of the present embodiment may be appropriately designed in consideration of dimensional tolerances and the like due to the vacuum brazing process as described above in advance (for example, designed to satisfy equations (2) and (3) as in Example 1 described later). Thereby, even when dimensional tolerances occur in the flange through-hole due to the vacuum brazing process, it is possible to engage the bearing with the flange through-hole as desired in the post-step of the vacuum brazing process.

[0044] The present embodiment only needs to have a bearing structure that can be inserted through the flange through-hole with elastic deformation as described above, and it is possible to appropriately apply common technical knowledge in various fields (such as the vacuum interrupter field, the bearing field, the mechanical joining field, the vacuum brazing field, etc.), and make design modifications by appropriately referring to prior art documents as necessary.

[0045] In addition, in the following Examples 1 and 2, for example, detailed descriptions are appropriately omitted by using the same reference numerals for similar contents. Also, in FIG. 2 described later, the dimensions t1, the clearance dimension C, the dimensional tolerance ΔT, and the play dimension α are each exaggerated for convenience of description.

[0046] ≪Example 1≫ <Main configuration example of a vacuum interrupter to which a bearing structure is applied> Based on FIGS. 1 to 5, a schematic configuration example of a vacuum interrupter 1A to which the bearing structure according to Embodiment 1 is applied will be described. In this vacuum interrupter 1A, a vacuum vessel 1 is provided, which is formed by sealing one side in the axial direction of an insulating cylindrical main body 10 with a fixed-side flange 1a and sealing the other side in the axial direction with a movable-side flange 1b.

[0047] In the case of the cylindrical main body 10 shown in FIG. 1, it mainly includes a cylindrical intermediate shield (arc shield) 20 that surrounds the outer peripheral sides of the fixed electrode 14a and the movable electrode 14b described later, a fixed-side insulating portion 21a continuously provided on one side in the axial direction of the intermediate shield 20, and a movable-side insulating portion 21b continuously provided on the other side in the axial direction of the intermediate shield 20.

[0048] Also, at the central portion of the intermediate shield 20, a fixed-side extending portion 20a that extends from the central portion to one side in the axial direction and overlaps with the inner peripheral side of the fixed-side insulating portion 21a, and a movable-side extending portion 20b that extends from the central portion to the other side in the axial direction and overlaps with the inner peripheral side of the movable-side insulating portion 21b are provided.

[0049] The fixed-side flange 1a has a disk-shaped portion 11a and an outer peripheral edge portion 12a that extends from the outer peripheral side of the disk-shaped portion 11a to the other side in the axial direction and is supported by the end face 2aa of the fixed-side insulating portion 21a, and has a structure forming a bottomed cylindrical shape as a whole.

[0050] At the central portion of the disk-shaped portion 11a, a columnar fixed-side current-carrying shaft 13a is provided so as to extend from the central portion to the other side in the axial direction (penetrating and extending from one side in the axial direction to the other side in the axial direction in FIG. 1). A fixed electrode 14a is supported at the end portion on the other side in the axial direction of the fixed-side current-carrying shaft 13a.

[0051] The movable-side flange 1b has a disk-shaped portion 11b and an outer peripheral edge portion 12b that extends from the outer peripheral side of the disk-shaped portion 11b to one side in the axial direction and is supported by the end face 2bb of the movable-side insulating portion 21b, and has a shape forming a bottomed cylindrical shape as a whole.

[0052] In the central portion of the disk-shaped portion 11b, a flange through-hole 3 having a shape that penetrates the central portion in the axial direction is provided, and a columnar movable-side energization shaft 13b is inserted through the flange through-hole 3 and extends in the axial direction.

[0053] A movable electrode 14b is supported at one end of the movable-side energization shaft 13b in the axial direction. Also, one side in the axial direction of the movable-side energization shaft 13b (the movable electrode 14b side) is supported inside the vacuum vessel 1 of the movable-side flange 1b via a cylindrical bellows 15 that is axially extendable and retractable and arranged coaxially with the movable-side energization shaft 13b. In the case of the movable-side energization shaft 13b in FIG. 1, a cylindrical bellows shield 16 is provided so as to cover and surround the outer peripheral side of the bellows 15.

[0054] In the flange through-hole 3, a bearing 4 capable of guiding the movable-side energization shaft 13b in the axial direction in a non-rotatable state is inserted through the flange through-hole 3 (inserted so as to be coaxially positioned on the outer peripheral side of the movable-side energization shaft 13b in the flange through-hole 3).

[0055] This bearing 4 has a structure that can be inserted through the flange through-hole 3 with elastic deformation (for example, having a flange-shaped portion 5 and a cylindrical wall portion 6 described later and being a structure that can be penetrated by a so-called snap-fit structure), and is provided so as to be non-rotatable with respect to the flange through-hole 3.

[0056] According to the vacuum interrupter 1A having the above configuration, while maintaining the vacuum state inside the vacuum vessel 1 (specifically, the outer peripheral side of the bellows 15 inside the vacuum vessel 1), the movable-side energization shaft 13b (and the movable electrode 14b) can be moved while being guided in the axial direction, and according to the movement of the movable-side energization shaft 13b, the movable electrode 14b can be brought into contact with and separated from the fixed electrode 14a (the contact point 14 can be brought into contact with and separated from).

[0057] The materials, shapes, etc. of the components of the vacuum interrupter 1A, as well as the processing methods and assembly methods of these components, can be appropriately applied in various modes according to the purpose of use of the vacuum interrupter 1A and the like.

[0058] For example, among the components of the vacuum interrupter 1A, insulating materials (such as alumina ceramics) are applied to the fixed-side insulating part 21a and the movable-side insulating part 21b, resin materials (such as heat-resistant resin materials) are applied to the bearing 4, and metal materials (such as stainless steel (SUS304), oxygen-free copper, titanium) are applied to others. However, it is preferable to appropriately select them assuming that expansion (thermal expansion) and residual stress may occur during the assembly of these components.

[0059] <Configuration example of bearing 4> In the bearing 4, it is a structure that can be inserted into the flange through-hole 3 with elastic deformation, and any structure that can move while guiding the movable-side energizing shaft 13b in the axial direction in a non-rotatable state can be applied, and various modes can be applied.

[0060] As an example, like the bearing 4 shown in FIGS. 1 to 4, it has a flange-shaped part 5 and a cylindrical wall part 6, and has a structure that can be inserted into the flange through-hole 3 with elastic deformation (a structure that can be penetrated by a so-called snap-fit structure).

[0061] The flange-shaped part 5 is an annular shape with a diameter larger than the opening diameter of the opening 3b on the other side in the axial direction in the flange through-hole 3, and has a shape that extends along the opening edge surface 31b of the opening 3b.

[0062] The cylindrical wall part 6 is a cylindrical shape extending from the inner peripheral edge part 51 of the flange-shaped part 5 to one side in the axial direction, and has a shape that can be inserted into the flange through-hole 3 from the other side in the axial direction toward one side in the axial direction. Also, the inner peripheral surface 6a side of the cylindrical wall part 6 has a shape that allows the movable-side energizing shaft 13b to be inserted into the inner peripheral surface side, and has a shape that guides the inserted movable-side energizing shaft 13b in the axial direction.

[0063] On the outer peripheral surface 6b of the cylindrical wall portion 6, a claw portion 61 having a shape protruding outward in the radial direction of the cylindrical wall portion 6 is formed. The outer diameter of the portion where the claw 61 portion is formed in the cylindrical wall portion 6 shall be larger than the opening diameter of the opening portion 3a on one side in the axial direction in the flange through hole 3.

[0064] Also, when the dimension between both the flange-shaped portion 5 and the claw portion 61 is L, and the dimension in the axial direction in the flange through hole 3 (the dimension equivalent to the thickness of the disk-shaped portion 11b in the figure) is T, it shall satisfy the following formula (1).

[0065] L ≧ T ……(1) The cylindrical wall portion 6 is provided with a slit hole 62 having a shape penetrating the cylindrical wall portion 6 in the radial direction. This slit hole 62 has a shape extending in the axial direction and an opening shape on the other side in the axial direction, and a plurality of them (4 in FIGS. 3 and 4) are formed at predetermined intervals in the circumferential direction of the cylindrical wall portion 6. As a result, in the four cylindrical wall portion pieces 60, which are the portions between the respective slit holes 62 in the circumferential direction of the cylindrical wall portion 6, one side in the axial direction of the cylindrical wall portion piece 60 is configured to be elastically deformable in the radial direction.

[0066] When such a cylindrical wall portion 6 of the bearing 4 is inserted into the flange through hole 3 from the other side in the axial direction toward one side in the axial direction, while the claw portion 61 of the cylindrical wall portion 6 is located within the flange through hole 3, one side in the axial direction of each cylindrical wall portion piece 60 elastically deforms inward in the radial direction. And after the claw portion 61 of the cylindrical wall portion 6 comes off from the flange through hole 3 toward one side in the axial direction, the cylindrical wall portion piece 60 elastically returns.

[0067] Thereby, the bearing 4 engages with the flange through hole 3 in a posture where the movable-side flange 1b (the hole wall of the flange through hole 3) is sandwiched in the axial direction by both the flange-shaped portion 5 and the claw portion 61, and it becomes easier to maintain the engaged state.

[0068] In the case of the claw portion 61 in the figure, it has a shape that protrudes outward in the radial direction as it approaches from one side in the axial direction to the other side in the axial direction. Further, the surface on the other side in the axial direction of the claw portion 61 is formed flat along the opening edge surface 31a of the opening portion 3a in the flange through hole 3. According to the claw portion 61 having such a shape, it becomes easier to insert the bearing 4 into the flange through hole 3, and in the bearing 4 after the insertion and engagement, the engagement state is more likely to be maintained.

[0069] <An example of the method for assembling the bearing 4> Each component for making the inside of the vacuum vessel 1 in a vacuum state (in FIG. 1, the cylindrical main body 10, the fixed-side flange 1a, the movable-side flange 1b, the bellows 15, the movable-side energizing shaft 13b, etc.; hereinafter, simply referred to as vacuum state components as appropriate) can be assembled by a vacuum brazing process. However, in the case of the bearing 4, when the heat-resistant temperature of the bearing 4 is higher than the vacuum brazing temperature, it may be engaged in the pre-process of the vacuum brazing process, or it may be engaged in the post-process of the vacuum brazing process.

[0070] On the other hand, when the heat-resistant temperature of the bearing 4 is lower than the vacuum brazing temperature, the vacuum brazing process and the bearing engagement process can be performed in order as shown below. First, in the vacuum brazing process, a brazing material is appropriately arranged at the assembly location of the vacuum state components in advance, and the vacuum state components are assembled as shown in FIG. 1. Then, the assembled vacuum state components are heat-treated in a vacuum furnace for vacuum brazing.

[0071] By this vacuum brazing, the movable-side energizing shaft 13b is inserted into the flange through hole 3 and extends in the axial direction, and one side in the axial direction of the movable-side energizing shaft 13b is supported (brazed) inside the vacuum vessel 1 of the movable-side flange 1b via the bellows 15.

[0072] Next, in the bearing engagement step, first, the cylindrical wall portion 6 of the bearing 4 is disposed to face the other side in the axial direction of the movable-side energizing shaft 13b, and then it is fitted into the other side in the axial direction of the movable-side energizing shaft 13b. Then, in the fitted bearing 4, it is moved to one side in the axial direction and inserted through the flange through-hole 3 (inserted to the outer peripheral side of the movable-side energizing shaft 13b), thereby bringing it into the engagement state as shown in FIGS. 1 and 2.

[0073] In addition, after performing the vacuum brazing process as described above, if dimensional tolerances or the like occur in the flange through-hole 3, there is a possibility that the subsequent bearing engagement process may be hindered. In such a case, as shown below, it is possible to appropriately design the bearing 4 in consideration of dimensional tolerances or the like in advance.

[0074] First, let the dimensional tolerance of the hole diameter of the flange through-hole 3 be Δφ, the dimension in the protruding direction in the claw portion 61 be t1, the clearance dimension between both the cylindrical wall portion 6 and the movable-side energizing shaft 13b be C, the dimensional tolerance related to the dimension T in the axial direction in the flange through-hole 3 be ΔT, and the dimension of the clearance (for example, an extremely narrow gap) provided between the opening edge surface 31a of the opening portion 3a and the claw portion 61 in the flange through-hole 3 be α. Design the bearing 4 so as to satisfy the following formulas (2) and (3).

[0075] Δφ < t1 < C ……(2) L = T + ΔT + α ……(3) According to the bearing 4 designed in this way, even if dimensional tolerances or the like occur in the flange through-hole 3 after the vacuum brazing process, the bearing engagement process can be appropriately carried out, and it is possible to engage with the flange through-hole 3 as desired.

[0076] <Configuration example of making the movable-side energizing shaft 13b non-rotatable> The configuration for making the movable-side energizing shaft 13b non-rotatable with respect to the cylindrical wall portion 6 of the bearing 4 is not particularly limited, and various aspects can be applied.

[0077] As an example, an outer peripheral flat surface 13d having a shape along the tangent plane of the outer peripheral surface 13c is formed on the outer peripheral surface 13c of the movable-side energizing shaft 13b, and an inner peripheral flat surface 6c having a shape along the outer peripheral flat surface 13d is formed at a position on the inner peripheral surface 6a of the cylindrical wall portion 6 facing the outer peripheral flat surface 13d.

[0078] According to such a configuration, even when a rotational force acts on the movable-side energizing shaft 13b, for example, the rotation of the movable-side energizing shaft 13b is suppressed (the non-rotatable state is maintained) by the outer peripheral flat surface 13d and the inner peripheral flat surface 6c coming into contact with each other.

[0079] Such outer peripheral flat surfaces 13d and inner peripheral flat surfaces 6c may be provided not only one by one but also a plurality of them at predetermined intervals in the circumferential direction. In FIG. 4, with respect to the outer peripheral surface 13c of the movable-side energizing shaft 13b, two outer peripheral flat surfaces 13d are formed so as to be parallel to each other, thus forming a so-called double-width shape.

[0080] Further, instead of simply providing a plurality of outer peripheral flat surfaces 13d and inner peripheral flat surfaces 6c respectively, they may be appropriately provided so as to be rotationally symmetric (180-degree rotationally symmetric in FIG. 4) with the axial direction as the axis of symmetry. In this case, in the movable-side energizing shaft 13b, the insertion posture when inserted into the bearing 4 has rotational symmetry, and the insertion operation (positioning, etc.) may be facilitated.

[0081] <Configuration example for making the bearing 4 in a non-rotatable state> The configuration for making the bearing 4 in a non-rotatable state with respect to the flange through-hole 3 is not particularly limited, and various aspects can be applied. For example, it is possible to apply the same aspect as the configuration for making the aforementioned movable-side energizing shaft 13b in a non-rotatable state (the configuration of forming the outer peripheral flat surface 13d and the inner peripheral flat surface 6c), but in addition, it is also possible to apply the aspect shown in Example 2 described later.

[0082] According to the above-described Example 1, without using an adhesive, bolts, etc., the bearing 4 can be inserted into and engaged with the flange through-hole 3, making it easier to maintain the engaged state and contributing to improvements in productivity and the like.

[0083] <<Example 2>> Next, an example of making the bearing 4 non-rotatable with respect to the flange through-hole 3 will be described. In this Example 2, for example, as shown in FIG. 5, a concave portion 32 is formed on the opening edge surface 31b of the opening portion 3b of the movable-side flange 1b. Further, for example, as shown in FIGS. 3 and 4, a convex portion 52 having a shape that can be fitted into the concave portion 32 is formed at a position on the flange-shaped portion 5 of the bearing 4 that faces the concave portion 32.

[0084] According to the configuration in which the concave portion 32 and the convex portion 52 are formed in this way, the bearing 4 can be engaged with the flange through-hole 3 so that the convex portion 52 is fitted into the concave portion 32. If the state in which the convex portion 52 is fitted into the concave portion 32 (hereinafter, simply referred to as the fitted state as appropriate) is maintained, even when a rotational force acts on the bearing 4, the rotation of the bearing 4 is suppressed (the non-rotatable state is maintained).

[0085] The convex portion 52 may be appropriately formed at a position facing the concave portion 32 as described above, but preferably, it is formed on the base portion side of the cylindrical wall portion piece 60 in the flange-shaped portion 5. As a result, the cylindrical wall portion piece 60 is thickened according to the shape, position, etc. of the convex portion 52, and the mechanical strength is improved.

[0086] The concave portion 32 and the convex portion 52 may be provided not only one by one but also a plurality of them (four each in FIGS. 3 to 5) at predetermined intervals in the circumferential direction.

[0087] Further, instead of simply providing a plurality of concave portions 32 and convex portions 52 respectively, it is also possible to provide them as appropriate so as to be rotationally symmetric (90-degree rotationally symmetric in FIG. 4) with the axial direction as the axis of symmetry. In this case, in the bearing 4, the engagement posture when engaging with the flange through-hole 3 has rotational symmetry, and the engagement operation (positioning, etc.) may be facilitated.

[0088] Further, after performing the vacuum brazing process as described above, if dimensional tolerances or the like occur in the flange through-hole 3, it is conceivable that the fitting state of the convex portion 52 with respect to the concave portion 32 cannot be maintained. In such a case, it is possible to appropriately design the bearing 4 so as to satisfy the following formula (4). Note that t2 in the following formula (4) indicates the dimension in the protruding direction of the convex portion 52.

[0089] t2>ΔT+α ……(4) According to the bearing 4 designed in this way, even if dimensional tolerances or the like occur in the flange through-hole 3 after the vacuum brazing process, the bearing engagement process can be appropriately carried out, and it becomes easier to maintain the fitting state of the convex portion 52 with respect to the concave portion 32.

[0090] According to the second embodiment shown above, in addition to achieving the same operational effects as the first embodiment, the following can be said. That is, in the flange through-hole 3 itself, since there is no need to design it considering the non-rotatable state, for example, by making it a shape that is relatively easy to create (for example, circular shape), it is possible to contribute to cost reduction and the like.

[0091] As described above, in the present invention, although only the specific examples described have been explained in detail, it is obvious to those skilled in the art that various changes and the like are possible within the scope of the technical idea of the present invention, and it is natural that such changes and the like belong to the scope of the claims.

Explanation of Signs

[0092] 1A… Vacuum interrupter, 1… Vacuum vessel, 1a… Fixed-side flange, 1b… Movable-side flange, 13b… Movable-side energizing shaft, 14a… Fixed electrode, 14b… Movable electrode, 15… Bellows 3… Flange through-hole, 32… Recess 4… Bearing 5… Flange-shaped part, 52… Protrusion 6… Cylindrical wall part, 60… Cylindrical wall part piece, 61… Claw part, 62… Slit hole

Claims

1. In a vacuum vessel having an insulating cylindrical main body, among a fixed electrode and a movable electrode provided opposite to each other in the axial direction of the cylindrical main body, a bearing structure of a movable-side current-carrying shaft that supports the movable electrode so as to be movable in the axial direction, The cylindrical main body has a fixed side on one side in the axial direction sealed by a fixed-side flange, and a movable side on the other side in the axial direction sealed by a movable-side flange, The movable-side flange is provided with a flange through-hole penetrating the movable-side flange in the axial direction, The movable-side current-carrying shaft is inserted through the flange through-hole and extends in the axial direction, and one side of the movable-side current-carrying shaft is supported inside the vacuum vessel of the movable-side flange via a bellows that is stretchable in the axial direction, A bearing that guides the movable-side current-carrying shaft in the axial direction in a non-rotatable state is provided in the flange through-hole in a non-rotatable state with respect to the flange through-hole, The bearing is An annular shape having a diameter larger than the opening diameter of the opening on the other side of the flange through-hole, and extending along the opening edge surface of the opening on the other side, a flange-shaped portion, A cylindrical shape extending from the inner peripheral edge portion of the flange-shaped portion to the one side, inserted into the flange through-hole from the other side to the one side, and a cylindrical wall portion that guides the movable-side current-carrying shaft inserted into the inner peripheral surface side of the cylindrical shape in the axial direction, And has, The cylindrical wall portion is On the outer peripheral surface of the cylindrical wall portion, a claw portion having a shape protruding outward in the radial direction of the cylindrical wall portion is formed, A plurality of slit holes having a shape extending in the axial direction through the cylindrical wall portion in the radial direction and opening to the one side are formed at predetermined intervals in the circumferential direction of the cylindrical wall portion, Each cylindrical wall portion piece, which is a portion between each of the slit holes in the circumferential direction of the cylindrical wall portion, is elastically deformable in the radial direction, The outer diameter of the portion where the claw portion is formed in the cylindrical wall portion is larger than the opening diameter of the opening on the one side in the flange through-hole, A bearing structure of a movable-side current-carrying shaft, characterized in that when the dimension between both the flange-shaped portion and the claw portion is L and the dimension in the axial direction in the flange through-hole is T, the following formula (1) is satisfied. L≧T ……(1)

2. When the dimensional tolerance of the hole diameter of the flange through-hole is Δφ, the dimension in the protruding direction in the claw portion is t1, the clearance dimension between both the cylindrical wall portion and the movable-side energization shaft is C, the dimensional tolerance related to T is ΔT, and the dimension of the clearance provided between both the opening edge surface of the opening on one side and the claw portion is α, the bearing structure of the movable-side energization shaft according to claim 1, characterized by satisfying the following formulas (2) and (3). Δφ < t1 < C …… (2) L = T + ΔT + α …… (3)

3. The claw portion has a shape protruding outward in the radial direction as it approaches from the one side to the other side, and the surface on the other side of the claw portion is formed flat along the opening edge surface of the opening on the one side in the flange through-hole, the bearing structure of the movable-side energization shaft according to claim 1, characterized by this.

4. At least one recess is formed in the opening edge surface of the opening on the other side, and the bearing structure of the movable-side energization shaft according to claim 1, characterized in that a convex portion that can be fitted into the recess is formed at a position facing the recess in the flange-shaped portion.

5. The recesses are formed in a plurality at a predetermined interval in the circumferential direction with respect to the opening edge surface of the opening on the other side, and are formed to be rotationally symmetric on the opening edge surface when the axial center direction is the axis of symmetry, the bearing structure of the movable-side energization shaft according to claim 4, characterized by this.

6. The convex portion is formed on the base portion side of the cylindrical wall portion piece in the flange-shaped portion, the bearing structure of the movable-side energization shaft according to claim 4, characterized by this.

7. When the dimensional tolerance related to T is ΔT, the dimension of the clearance provided between both the opening edge surface of the opening on the one side and the claw portion is α, and the dimension in the protruding direction of the convex portion is t2, the bearing structure of the movable-side energization shaft according to claim 4, characterized by satisfying the following formula (4). t2 > ΔT + α …… (4)

8. A vacuum interrupter, characterized by having the bearing structure of the movable-side energization shaft according to any one of claims 1 to 7.

9. A method for manufacturing the vacuum interrupter according to claim 8, a vacuum brazing step of brazing one side of the movable-side energization shaft inside the vacuum container of the movable-side flange via the bellows in a state where the movable-side energization shaft is inserted through the flange through-hole and extends in the axial direction After the vacuum brazing step, a bearing engaging step of fitting the bearing into the flange through hole from the other side of the movable side energizing shaft is provided. A method for manufacturing a vacuum interrupter, characterized by having the above.

Images