Insulation rod and switch

Abstract

An insulation rod (10) comprising: a spring receiver (7C); a metal insert (13) in the form of a bottomed cylinder in which the upper end is open, the metal insert accommodating the spring receiver (7C) so as to enable movement within a predetermined range along the inner peripheral surface of the metal insert (13); and an insulating portion (9) that electrically insulates the outer peripheral surface of the metal insert (13). A bottom plate portion (13B) of the metal insert (13) and a body portion (13A) of the metal insert (13) are configured as separate bodies, and a biased spring (S) is provided between a lower surface of the spring receiver (7C) and the bottom plate portion (13B) of the metal insert (13).

Description

Insulating rods and switches

[0001] The present application relates to an insulating rod and a switch.

[0002] A typical insulating rod is a component that constitutes a high-voltage switch and has the functions of insulating the main circuit, which is the high-voltage charging part, from the grounded part, withstanding the load when the switch is opened and closed, and applying contact pressure to the contacts in the closing direction of the switch when the switch is in the closed state, thereby pressing the contacts and reducing contact resistance (see, for example, Patent Document 1).

[0003] In Patent Document 1, a flange portion that receives a contact pressure spring is provided on the filler metal of the insulating rod, and this flange portion receives the force of the spring when opening and closing.

[0004] Japanese Patent Application Publication No. 10-321089

[0005] In the insulating rod disclosed in Patent Document 1, the load of the spring is received by the flange portion provided on the filler metal during the opening operation of the switch, and the load is received by the bottom portion of the filler metal during the closing operation. However, when opening and closing are repeated, the metal at the bottom portion of the filler metal peels off from the insulator covering the filler metal, making the contact between the metal at the bottom portion of the filler metal and the insulator unstable, and the insulator near the bottom portion of the filler metal is worn away by the impact when the switch is opened and closed, creating a tiny gap, which poses a risk of degrading electrical performance.

[0006] Countermeasures for this risk include increasing the dimensions between the filler metal and the grounding point to ensure an insulating distance for use in a low electric field, or applying conductive paint, but these methods have issues such as increased production costs and worsened workability during production.

[0007] The present application discloses a technique for solving the above-mentioned problems, and aims to provide an insulating rod and a switch that are low-cost and easy to produce.

[0008] The insulating rod disclosed in the present application comprises: a spring bearing; a cylindrical filler metal with a closed bottom and an open upper end that accommodates the spring bearing movably within a predetermined range along its inner circumferential surface; and an insulating portion that electrically insulates the outer circumferential surface of the filler metal, wherein the bottom plate portion of the filler metal and the main body portion of the filler metal are configured as separate bodies, and a biased spring is provided between the lower surface of the spring bearing and the bottom plate portion of the filler metal. The insulating rod disclosed in the present application comprises: a spring bearing; a cylindrical filler metal with a closed bottom and an open upper end that accommodates the spring bearing movably within a predetermined range along its inner circumferential surface; and an insulating portion that electrically insulates the outer circumferential surface of the filler metal, and a plurality of biased disc springs are provided between the lower surface of the spring bearing and the upper surface of the insulating portion that seals the lower end of a hollow portion inside the filler metal, and the upper surface of the insulating portion has a second counterbore portion that has the same shape as the disc spring when the disc spring is not biased. The switch disclosed in the present application also has an insulating rod.

[0009] According to the insulating rod and the switch disclosed in the present application, it is possible to provide an insulating rod and a switch that are low cost and easy to produce.

[0010] FIG. 2A is a schematic cross-sectional view of the switch in a closed state according to embodiment 1. FIG. 2B is a schematic cross-sectional view of the switch in a state at the moment when the main contacts of the switch in embodiment 1 make and release contacts. FIG. 2C is a schematic cross-sectional view of the switch in an open state according to embodiment 1. FIG. 2B is a schematic cross-sectional view of the switch in a closed state according to embodiment 1. FIG. 2C is a schematic cross-sectional view of the switch in an open state according to embodiment 1. FIG. 5A is a schematic cross-sectional view of the main part of the insulating rod in a closed state according to embodiment 1. FIG. 5B is a schematic cross-sectional view of the main part of the insulating rod in an open state according to embodiment 1. FIG. 5B is a schematic cross-sectional view of the main part of the insulating rod as a comparative example. FIG. 5C is a schematic cross-sectional view of the main part of the insulating rod according to embodiment 2. FIG. 5D is a schematic side view of the filler according to embodiment 2. FIG. 5E is a schematic cross-sectional view of the main part of the insulating rod according to embodiment 3.

[0011] Embodiment 1. An insulating rod and a switch according to embodiment 1 will be described below with reference to the drawings. In this specification, the axial direction Z refers to the axial direction of the fixed current-carrying shaft and the movable current-carrying shaft, which will be described later, with the fixed contact side being defined as the top and the opposite side being defined as the bottom. This direction coincides with the opening and closing direction of the switch.

[0012] FIG. 1 is a schematic diagram showing the configuration of a main circuit section of a switch 100 according to embodiment 1. FIG. 2A is a schematic cross-sectional view of the switch 100 in a closed state. FIG. 2B is a schematic cross-sectional view of the switch 100 at the moment when the main contacts are about to make or release contact. FIG. 2C is a schematic cross-sectional view of the switch 100 in an open state. FIGS. 2A to 2C show the movement of the insulating rod 10 accompanying the operation of the switch 100. Note that to make it easier to understand the internal structure of the insulating rod, the main parts of the insulating rod 10 in FIGS. 2A to 2C are shown in cross-section.

[0013] The switch 100 has a vacuum interrupter 2 and a switching mechanism 5 that opens and closes a fixed contact 6 and a movable contact 7, both of which are electrically conductive and housed in the vacuum interrupter 2.

[0014] The vacuum interrupter 2 includes an insulating container 21, a fixed contact 6, a movable contact 7, a fixed conductive shaft 63, and a movable conductive shaft 73. The insulating container 21 is a cylindrical container made of an insulating material, and the inside of the insulating container 21 is sealed from the outside air.

[0015] The fixed contact 6 is joined to a rod-shaped fixed current-carrying shaft 63 that penetrates from the inside to the outside of the insulating container 21. The movable contact 7 is disposed opposite the fixed contact 6 and is connected to a rod-shaped movable current-carrying shaft 73 that penetrates from the inside to the outside of the insulating container 21. The fixed current-carrying shaft 63 and the movable current-carrying shaft 73 are conductive. The movable contact 7 can be moved toward and away from the fixed contact 6.

[0016] A bellows-like bellows (not shown) is arranged around the movable current-carrying shaft 73, which seals the inside of the vacuum interrupter 2 in a vacuum even when the movable current-carrying shaft 73 moves in the axial direction Z. The vacuum interrupter 2 configured in this manner can open and close the movable contact 7 relative to the fixed contact 6 while maintaining a vacuum inside the vacuum interrupter 2. The end of the fixed current-carrying shaft 63 opposite the fixed contact 6 is connected to the upper terminal 3, and the movable current-carrying shaft 73 is connected to the lower terminal 4 by a flexible conductor 8.

[0017] Fig. 3 is a cross-sectional view of a main part of the insulating rod 10. Fig. 4 is a schematic side view of the filler metal 13. The insulating rod 10 has a spring retainer 7C, a spring S, the filler metal 13, and an insulating part 9. In other words, the insulating rod 10 is a part that is driven by the opening and closing mechanism 5. The movable conductive shaft 73 of the vacuum interrupter 2 and the spring retainer 7C of the insulating rod 10 are connected by a connecting rod 11.

[0018] The spring retainer 7C is cylindrical, and the lower end of the connecting rod 11 (see the bottom of the drawing in FIG. 2A ) is connected to its upper surface. The lower surface 7CU of the spring retainer 7C contacts the upper end of the spring S, and the lower end of the spring S contacts the bottom plate portion 13B of the filler metal 13, which will be described in detail later. The spring S is biased and disposed between the spring retainer 7C and the bottom plate portion 13B of the filler metal 13, and is capable of expanding and contracting inside the filler metal 13. The outer periphery of the lower end of the spring retainer 7C has a flange portion 7CF (first flange portion) that protrudes outward. The flange portion 7CF is housed within the filler metal 13 and is movable within a predetermined range in the axial direction Z along the inner circumferential surface of the filler metal 13.

[0019] The filler metal 13 is made of metal and has a cylindrical main body portion 13A and a bottom plate portion 13B that seals the opening at the bottom end of the main body portion 13A. When the main body portion 13A and the bottom plate portion 13B are combined, the filler metal 13 becomes a bottomed cylinder. The outer peripheral surface of the main body portion 13A is provided with an anchor portion 13C that protrudes outward in a flange or spiral shape. The inner upper end of the main body portion 13A also has a flange portion 13F (second flange portion) that protrudes inward. The outer peripheral surface of the filler metal 13 is covered with an insulating portion 9 that has electrical insulation properties.

[0020] The insulating portion 9 is molded by fitting the bottom plate portion 13B into a counterbore portion 13Z (first counterbore portion) provided on the inside of the lower end of the main body portion 13A under molding pressure, so that the insulating material does not flow into the filler metal 13 after molding of the insulating portion 9. (Methods of placement include bolts, magnets, etc.)

[0021] The spring bearing 7C is movable in the axial direction Z along the inner peripheral surface of the cylindrical main body portion 13A of the filler metal 13. Here, the inner diameter of the flange portion 13F of the filler metal 13 is smaller than the outer diameter of the flange portion 7CF of the spring bearing 7C. Therefore, the flange portion 13F interferes with the flange portion 7CF, so the spring bearing 7C does not completely protrude outside the main body portion 13A of the filler metal 13 in the axial direction Z.

[0022] Next, the operation of the switch 100 will be described. Fig. 5A is a cross-sectional view of a main portion of the insulating rod 10 in a closed state. Fig. 5B is a cross-sectional view of a main portion of the insulating rod 10 in an open state. To open the switch 100 from the closed state shown in Fig. 2A, the insulating portion 9 is pulled downward in the plane of the drawing in Fig. 3 by a pin (not shown) inserted through the driving pin through-hole 13H shown in Fig. 3. At this time, the space K shown in Fig. 5A that existed in the axial direction Z between the flange portion 13F of the filler metal 13 and the flange portion 7CF of the spring holder 7C gradually decreases, and the fixed contact 6 and the movable contact 7 reach the state shown in Fig. 2B while they are in abutting contact with each other. Thereafter, the flange portion 7CF of the spring holder 7C interferes with the flange portion 13F of the filler metal 13, pulling the entire insulating rod 10 downward, and the movable contact 7 is separated from the fixed contact 6, reaching the open state shown in Fig. 2C.

[0023] At this time, the spring S takes on the maximum length within the filler metal 13 throughout the entire operation of the switch 100, but this length is shorter than the natural length of the spring S. Therefore, the insulating rod 10 is configured so that the contact pressure of the spring S against the spring receiver 7C is not lost during the operation of the switch 100.

[0024] Furthermore, when the switch 100 is opened, the movable current-carrying shaft 73 is pulled downward to open the switch 100, and as a reaction to this, a tensile load acting upward in the axial direction Z (towards the fixed contacts) is generated in the main body 13A of the filler metal 13. This load is borne by the anchor portion 13C provided on the outer circumferential surface of the main body 13A.

[0025] Furthermore, by performing the reverse operation of this opening operation, the switch 100 changes from the open state shown in Fig. 2C to the closed state shown in Fig. 2A. That is, when the switch 100 is closed, the insulating part 9 is pushed upward in the plane of the paper in Fig. 3 by a pin (not shown) passed through the driving pin through hole 13H. The movable contact 7 gradually approaches the fixed contact 6, and eventually reaches the state shown in Fig. 2B. When the insulating part 9 is further pushed up, the movable contact 7, movable current-carrying shaft 73, connecting rod 11, and spring retainer 7C, which are connected in this order, cannot rise any further, so the spring S is gradually compressed.

[0026] Then, the repulsive force of the spring S presses the movable contact 7 against the fixed contact 6 to create a closed circuit. At this time, a space K is generated between the flange portion 7CF of the spring receiver 7C and the flange portion 13F of the filler metal 13 in the axial direction Z.

[0027] When the switch 100 is in a closed state, the spring S applies contact pressure to the movable contact 7 toward the fixed contact 6. At this time, a similar contact pressure is generated in the opposite direction of the spring S, and this force is received by the bottom plate portion 13B of the filler metal 13. At this time, because the main body portion 13A and the bottom plate portion 13B are independent of each other, the lower surface of the bottom plate portion 13B is pressed against the insulating portion 9 with which it is in contact. As a result, both contact surfaces 91 shown in FIG. 3 are stabilized, and it is possible to prevent a minute gap from occurring between the bottom plate portion 13B and the insulating portion 9.

[0028] 6 is a cross-sectional view of a main portion of an insulating rod 10B as a comparative example. The filler metal 13X that holds the spring retainer 7C has a cup-shaped structure, and the main body 13XA and the bottom 13XB are integrally formed. When such a filler metal 13X is used in a switch, during the above-mentioned circuit-opening operation of the switch, the filler metal 13X is pulled upward in the axial direction Z by a reaction to the circuit-opening operation, and this force is received by the anchor portion 13XC provided on the outer peripheral surface of the main body 13XA of the filler metal 13X.

[0029] Furthermore, during the circuit closing operation, the insulating rod 10B is pushed up by the pin, and the spring S is driven while being compressed, so that the filler metal 13X receives the load from the spring S at the bottom 13XB. Since the main body 13XA and the bottom 13XB of the filler metal 13X are integral with each other, the load on the bottom 13XB acts as a force that stretches the main body 13XA of the filler metal 13X in the axial direction Z, so that the load is completed within the filler metal 13X, and no load that stabilizes the contact surface 91 with the filler metal 13X is generated on the insulating part 9 that contacts the bottom 13XB of the filler metal 13X.

[0030] On the other hand, when the switch 100 according to the first embodiment is in the open state, the spring S is stretched by the action of the insulating rod 10 compared to the closed state, but as described above, the spring S does not lose all of its contact pressure load and continues to press the bottom plate portion 13B. Therefore, the load generated by the spring S stabilizes the contact surface 91, as in the closed state, and it is possible to prevent a minute gap from occurring between the contact surface 91 and the insulating portion 9.

[0031] In the comparative example, the load of the spring S, which was contained within the filler metal 13X, affects the insulating portion 9 in the present embodiment 1, but this is not a strength concern as long as the bottom plate portion 13B has a seating surface that can sufficiently alleviate the surface pressure relative to the strength of the insulating portion 9. The edges of the main body portion 13A and the bottom plate portion 13B are processed so that burrs and burrs are not permitted, and by eliminating them, stress concentration is prevented.

[0032] In the insulating rod 10 and switch 100 according to the first embodiment, the filler metal 13 is configured as two separate components, the main body portion 13A and the bottom plate portion 13B, so that the bottom plate portion 13B of the filler metal 13 is pressed against the insulating portion 9 when the switch 100 is in both the closed and open states. This stabilizes the contact surface 91 between the bottom plate portion 13B and the insulating portion 9, and prevents a minute gap from occurring between them due to wear of the insulating portion 9. This also improves the electrical performance of the insulating rod.

[0033] Furthermore, there is no longer a need for conventional countermeasures against the occurrence of minute gaps, such as increasing the dimension between the filler metal and the grounding point to ensure an insulating distance or applying conductive paint, which improves workability during manufacturing and reduces costs.

[0034] Furthermore, while the filler metal 13X of the comparative example is manufactured by boring out the blind holes 13Xh of the filler metal 13 by cutting, the filler metal 13 of the present embodiment can be manufactured by providing the through holes 13h in the main body 13A, improving the workability of the filler metal 13. Furthermore, plating solution does not accumulate during surface treatment, improving product quality. Furthermore, while the filler metal 13X of the comparative example is manufactured by processing bar stock, the filler metal 13 of the present application can be manufactured from pipe stock, which reduces processing costs and makes effective use of materials.

[0035] Embodiment 2. An insulating rod and a switch according to Embodiment 2 will now be described, focusing on the differences from Embodiment 1. Fig. 7 is a cross-sectional view of a main portion of an insulating rod 210. Fig. 8 is a schematic side view of a filler metal 213. The filler metal 213 has a structure modified from that of Embodiment 1 for integrating the filler metal with the insulating portion 9 and preventing the insulator from flowing into the filler metal due to the molding pressure applied when molding the insulating portion 9. In Embodiment 2, instead of providing a counterbore in the main body portion 213A, a protrusion 213BT protruding upward is formed on the top surface of the bottom plate portion 213B, and the protrusion 213BT is fitted into the lower end of the main body portion 213A in the axial direction Z so as to plug it.

[0036] When the switch 100 is opened or closed, the insulating rod 210 operates in the same manner as in embodiment 1. Therefore, the force generated in the filler metal 213 of the insulating rod 210 by opening or closing the switch 100 is the same as that described in embodiment 1. Therefore, the bottom plate portion 213B is pressed against the insulating portion 9 regardless of the open or closed state of the switch 100, similar to the bottom plate portion 13B in embodiment 1.

[0037] The insulating rod and the switch according to the second embodiment have the same effects as those of the first embodiment.

[0038] Embodiment 3. An insulating rod and a switch according to Embodiment 3 will be described below, focusing on the differences from Embodiment 2. Figure 9 is a cross-sectional view of a main portion of an insulating rod 310. In Embodiment 3, the bottom plate portion 213B of the filler metal 213 described in Embodiment 2 is eliminated, and the structure is such that only the main body portion 213A is included. Furthermore, the spring 3S has a structure in which disc springs 31S are stacked one on top of another, and the insulating portion 9 is provided with a counterbore portion 92 (second counterbore portion) of the same shape as the bottom disc spring 31S when in its natural length (unbiased state), and the bottommost disc spring 31S substitutes for the bottom plate portions 13B and 213B described in Embodiments 1 and 2.

[0039] When the switch 100 is opened or closed, the insulating rod 310 operates in the same manner as in embodiment 2. Therefore, the force generated in the filler metal of the insulating rod 310 by opening or closing the switch 100 is the same as that described in embodiment 2. However, by eliminating the bottom plate portion 213B, the force that was received by the bottom plate portion 213B in embodiment 2 is instead received by the disc spring 31S located at the bottommost stage of the spring 3S.

[0040] In the second embodiment, the bottom plate portion 213B is pressed against the insulating portion 9 when the switch 100 is opened or closed, but in the third embodiment, the disc spring 31S is pressed against the insulating portion 9. The disc spring 31S attempts to expand in a direction perpendicular to the axial direction Z beyond its natural length, but cannot expand because the diameter of the counterbore portion 92 of the insulating portion 9 with which it is in contact is the natural long diameter of the disc spring 31S, and the insulating portion 9 and the counterbore portion 92 come into close contact with each other, stabilizing the contact surface.

[0041] According to the insulating rod and switch of embodiment 3, by adjusting the switch 100 and the insulating rod 310 so that the impact when the switch 100 is opened or closed is a load that does not cause damage or creep to the insulating part 9, it is possible to prevent a minute gap from occurring between the insulating part 9 and the lowest-layer disc spring 31S, thereby improving the electrical performance of the insulating rod 310 and the switch 100.

[0042] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations.

[0043] Therefore, countless variations not illustrated are conceivable within the scope of the technology disclosed in this application, including, for example, cases where at least one component is modified, added, or omitted, and cases where at least one component is extracted and combined with a component of another embodiment.

[0044] 100 Switch, 10, 10B, 210, 310 Insulating rod, 11 Connecting rod, 13, 13X, 213 Filler metal, 13A, 213A, 13XA Main body, 13B, 213B Bottom plate, 13XB Bottom, 13C, 13XC Anchor, 13F, 7CF ​​Flange, 213BT Convex, 13h Through hole, 13H Drive pin through hole, 13Xh Blind hole, 13Z Counterbore, 2 Vacuum valve, 21 Insulating container, 3 Upper terminal, S, 3S Spring, 31S Disc spring, 4 Lower terminal, 5 Opening and closing mechanism, 6 Fixed contact, 63 Fixed current-carrying shaft, 7 Movable contact, 73 Movable current-carrying shaft, 7C Spring holder, 7CU Underside, 8 Conductor, 9 Insulating part, 91 Contact surface, K space, Z axis direction.

Claims

1. A spring receiver, a bottomed cylindrical insert that houses the spring receiver movably within a predetermined range along an inner peripheral surface and has an open upper end, and an insulating portion that electrically insulates an outer peripheral surface of the insert, wherein a bottom plate portion of the insert and a main body portion of the insert are configured as separate bodies, and an insulating rod having a spring biased between a lower surface of the spring receiver and a bottom plate portion of the insert.

2. The spring receiver includes a first flange portion that protrudes outward on an outer peripheral surface at a lower end, the insert includes a second flange portion that protrudes inward on an inner peripheral surface at an upper end, an inner diameter of the second flange portion of the insert is smaller than an outer diameter of the first flange portion of the spring receiver, and the first flange portion is housed inside the insert. The insulating rod according to claim 1.

3. The insulating rod according to claim 1 or claim 2, comprising a flange-shaped or spiral anchor portion that protrudes outward on an outer peripheral surface of the insert.

4. The main body portion of the insert is cylindrical, and the bottom plate portion of the insert is fitted into a first countersunk portion provided at a lower end of an inner peripheral surface of the main body portion. The insulating rod according to claim 1 or claim 2.

5. The main body portion of the insert is cylindrical, the bottom plate portion of the insert includes a convex portion that protrudes upward at a central portion, and the convex portion is fitted into a lower end of an inner peripheral surface of the main body portion. The insulating rod according to claim 1 or claim 2.

6. A spring receiver, a bottomed cylindrical insert that houses the spring receiver movably within a predetermined range along an inner peripheral surface and has an open upper end, and an insulating portion that electrically insulates an outer peripheral surface of the insert, wherein a plurality of disc springs biased are provided between a lower surface of the spring receiver and an upper surface of the insulating portion that seals a lower end of a cavity inside the insert, and the upper surface of the insulating portion has a second countersunk portion having the same shape as the disc spring in a state where the disc spring is not biased. The insulating rod.

7. The spring receiver includes a first flange portion that protrudes outward on an outer peripheral surface at a lower end, the insert includes a second flange portion that protrudes inward on an inner peripheral surface at an upper end, an inner diameter of the second flange portion of the insert is smaller than an outer diameter of the first flange portion of the spring receiver, and the first flange portion is housed inside the insert. The insulating rod according to claim 6.

8. The insulating rod according to claim 6 or claim 7, comprising a flange-shaped or spiral anchor portion that protrudes outward on an outer peripheral surface of the insert.

9. A switch having an insulating rod according to any one of claims 1, 2, 6, and 7.