JP2596142B2 - Vacuum valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vacuum valve constituting a current interrupting portion of a vacuum switchgear such as a vacuum switchgear, a vacuum circuit breaker, and the like. A rod-shaped fixed contactor conductor inserted with a gap in a hole provided at the center of the insulator, a joining surface that is joined by being wound around one of the axial end surfaces of the insulator. The fixed contactor-side end of the metal cylinder, which is connected to the insulator via a connecting member made of a metal plate to form a vacuum vessel and has the same potential as the movable contact, has an axial edge with the insulation. The insulating member is provided via a connecting member made of a metal plate and having a joining surface along one of the surfaces along the outer peripheral edge of the end surface and joined in a ring shape while maintaining insulation with the joining member on the fixed contact conductor side. Each connection part in the vacuum valve connected to the body Of about the structure.

[Conventional technology]

FIG. 4 shows a conventional traveling valve of this type. Above the metal cylinder 9 having the same potential through the movable contact 7 and the metal bellows 8 penetrating the hole of the low surface 9a, the material is made of special ceramics which is made of both electric and mechanical characteristics. An insulating cylinder 1 is arranged coaxially with a metal cylinder 9, and a rod-shaped fixed contact conductor 3 inserted inside the insulating cylinder 1 with a gap provided between the insulating cylinder 1 and the inner peripheral surface of the insulating cylinder 1.
And the upper end of the metal cylinder 9 is connected to the lower end of the insulating cylinder 1 via a drilled flange 5a of a seal 5 having an L-shaped cross section.

In this configuration, the insulation between the fixed contact conductor 3 in the open state of the vacuum valve, the movable contact 7 and the metal cylinder 9 at the cylinder potential depends on the axial length of the outer peripheral surface of the insulating cylinder 1 on the atmosphere side. On the vacuum side, the shield 5 is secured by the axial length of the inner peripheral surface of the insulating cylinder 1 so that metal vapor generated from the fixed contact 2 and the movable contact 6 when current is interrupted is prevented.

FIG. 3 shows another conventional example of a vacuum valve of this type. In this configuration, the vacuum valve is formed by using a small insulating plate of the same material instead of the insulating cylinder made of expensive special ceramics in the vacuum valve of FIG. A rod-shaped fixed contact conductor 13 inserted through the center hole of the insulating plate 11 with a gap therebetween is connected to the inner peripheral side of the lower end surface of the insulating plate 11 via a metal disk 14.
Is connected to the outer peripheral side of the lower end surface of the insulating plate 11 via the ring-shaped flange portion 15a of the shield 15 having a mortar-shaped section.

In this configuration, the insulation between the fixed contact conductor 13 in the open state of the vacuum valve and the metal cylinder 9 having the same potential as the movable contact 7 is based on the axial length of the hole of the insulating plate 11 and the insulation on the atmosphere side. It is secured by the radial length of the upper surface of the plate and the axial length of the outer peripheral surface.
It is secured by the length along the radial direction of the groove surface of the ring-shaped groove 10 formed between the flange portion 15a and the flange portion 15a. The hole on the bottom surface of the shield 15 is formed to have a diameter smaller than the outer diameter of the fixed contact 2, so that the metal particles generated from the fixed contact 2 and the movable contact 6 do not directly hit the ring-shaped groove 10 when the current is cut off. The creepage insulation of the groove 10 is prevented from lowering.

[Problems to be solved by the invention]

Problems with the conventional vacuum valve configured as described above are as follows. In other words, the connection between the fixed contact conductor and the axial end surface of the insulating plate or insulating cylinder made of special ceramics is performed by cutting the rod-shaped fixed contact conductor to a stepped diameter to form a ring-shaped joining surface. The connection between the end of the metal cylinder and the axial end surface of the insulating plate or the insulating cylinder is performed through the ring-shaped flat surface of the disk, and the end of the metal cylinder is joined to the end of the metal cylinder by a ring-shaped joining surface, that is, a flange having a large surface strength. Is formed through a ring-shaped flat surface in the shield, and the metal disk and shield are made of a special alloy whose thermal expansion coefficient is close to that of special ceramics. Although the temperature drop is prevented, a large difference in thermal expansion coefficient between the special ceramics, the fixed contact conductor, and the metal cylinder causes a large force to act on the joint surface in the surface direction if the temperature change is large. For this reason,
For example, the insulating plate 11 shown in FIG.
Joint surfaces mutually in the metal disk or shield to the even can be the thickness L ₁ to reduce the thickness becomes thick in order to withstand the surface direction of the force of the joint surface, also to reduce the force acting on the bonding surface In order to reduce the transmitted force by increasing the distance between them, the size of the insulating plate or metal cylinder increases, and the size of the expensive special ceramic insulating plate or insulating tube or the size of the vacuum valve increases. There was a drawback that conversion could not be avoided.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a coupling structure that does not require a large-sized vacuum valve and an insulating plate or an insulating cylinder without changing the material of a member constituting the vacuum valve even in an environment where a temperature change is large. .

[Means for solving the problem]

In order to solve the above-mentioned problems, in the present invention, a rod-shaped fixed contact conductor inserted through a hole provided at the center of a plate-shaped or cylindrical insulator made of ceramics with a gap therebetween is formed of the insulator. It is joined to the insulator via a joining member made of a metal plate and has a joining surface that is joined by surrounding one of the axial end surfaces with a hole. The fixed contactor side end of the metal cylinder is joined to one of the axial end faces of the insulator along the outer peripheral edge of the end face and in a ring shape while maintaining insulation with the coupling member on the fixed contact conductor side. Having a mating surface,
A vacuum valve coupled to the insulator via a coupling member made of a metal plate is connected to the coupling end side of the stationary contact conductor side and the coupling end side of the metal cylindrical end side of the coupling surface of the coupling member with the insulator. Each having a cylindrical portion extending in the axial direction from the periphery of the joint surface with the insulator.

[Action]

By forming the coupling member in this manner, the joint surface and the cylindrical portion connected to the peripheral edge of the joint surface and extending in the axial direction each form one side of an L-shaped cross section. Therefore, 1
The forces acting between one joint surface and the other joint surface of the two coupling members are absorbed by the L-shaped axial side, and the transmitted force is significantly reduced. Thus, for example, it is not necessary to increase the thickness, increase the diameter, or increase the size of the metal cylinder of the insulating plate shown in FIG. 3, and it is possible to prevent the insulating plate and the vacuum valve from being enlarged. Also, since a large force does not act on the joint surface,
In particular, a high-reliability vacuum valve can be obtained which is small, inexpensive, and requires no high-strength bonding material.

〔Example〕

FIG. 1 shows a first embodiment of the present invention. In the figure, the same members as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. On the lower surface of the insulating plate 21 made of special ceramic, a joint surface ground to the same plane with the ring-shaped groove 10 formed therebetween is formed, and is connected to the joint surface periphery of the joint member 2 joined to the inner joint surface. forming an L-shaped cross-section with this joining surface extending in the axial direction Te, the cylindrical portion of the length l ₁ is formed. Therefore to allow a cylindrical portion forming a gap a between the fixed contacts conductor 13 and the holes of the insulating plate 21 is the pore size to be larger than the thickness t ₁ of the coupling member are determined. Then, a flange portion bent rightward from the upper end of the L-shape is joined to the ring-shaped joining surface of the stepped diameter portion of the fixed contact conductor 13. Also it is bonded to the bonding surface of the outer, which is grinding, by connecting the joint surface periphery of the shield 25, together with the joint surface extends in the axial direction to form an L-shaped cross section, the cylindrical portion length l ₂ A part of the shield 25 is formed. A flange portion bent leftward from the lower end of the L-shape is joined to a flange formed on the upper end of the metal cylinder 9.

By forming the coupling members in this way,
The mechanical stress on the joint caused by the difference in the coefficient of thermal expansion between the insulating plate and the members other than the coupling member is 1 L-shaped in section.
The sides are absorbed by the cylindrical parts with lengths l ₁ and l ₂ , respectively.
The mechanical stress transmitted to the joint is significantly reduced. In addition, the ring-shaped groove side of the joint surface of the shield 25 is formed in a truncated cone shape as in the conventional case and covers the groove 10 so as to avoid direct impact of metal particles generated from both fixed and movable contacts when current is interrupted, and to reduce the gap. ₅ by suppressing the ingress portion of the metal particle flow F _1, which weakened momentum as possible as small to the extent that the breakdown voltage is ensured to prevent a decrease in the creeping breakdown voltage of the groove surface.

FIG. 2 shows a second embodiment of the present invention. Coupling member on the fixed contact conductor 13 side of insulating plate 31 made of special ceramics
The bonding surface with the metal cylinder 19 is set on the upper surface, and the bonding surface with the shield 26, which is a connecting member on the metal cylinder 19 side, is set on the lower surface. When the insulating plate 31 is formed in this manner, the junction surface of the fixed contact conductor-side coupling member 2 in the first embodiment can be used as a creeping insulating surface, the required creepage also as a flat plane d ₁ as shown in FIG. Since the distance can be obtained, the amount of special ceramics used can be reduced. Further, since it is possible to form the barrier l ₄ of the joint surface of the shield 26 flat stretched inward suppressing intrusion amount of the metal particle flow F _2, the fixed contact 2 upward than in the first embodiment It can be shifted, and the metal cylinder 19 can be formed short. On the other hand, creepage insulation distance of the atmosphere-side so that the amount becomes smaller joint surface, to ensure a required creepage distance by forming the convex portion P ₃ on the outer side of the joint surface. The height of the convex portion P ₃ in order to facilitate the grinding of the convex portion P ₁ the coupling member 12 is joined, it is formed slightly below the projecting portion P _1.

〔The invention's effect〕

As described above, in the present invention, a rod-shaped fixed contact conductor inserted with a gap in a hole provided at the center of a plate-shaped or cylindrical insulator made of ceramics,
A movable contact which is connected to the insulator via a joining member made of a metal plate and has a joining surface which is joined by surrounding one of the end faces in the axial direction of the insulator; The fixed contact side end of the metal cylinder that has the same potential as
A connection made of a metal plate having a connection surface along one of the axial end surfaces of the insulator along a peripheral edge of the end surface and bonded to the connection member on the fixed contact conductor side while maintaining insulation from the connection member; A vacuum valve coupled to the insulator via a member is provided at the coupling end side of the fixed contact conductor side and the coupling end side of the metal cylinder end side of the joint surface of the coupling member with the insulator, respectively. Due to the structure having a cylindrical portion extending in the axial direction from the periphery of the joint surface with the body, due to the difference in thermal expansion coefficient between the insulating plate or insulating cylinder made of ceramics and the components of the vacuum valve excluding the coupling member, Even if a force is to be applied from one joint surface to the other joint surface of one coupling member, the force is absorbed by the cylindrical portion forming an L-shaped cross section together with the joint surface and transmitted to the other joint surface. Is significantly reduced Therefore, it is no longer necessary to reduce the transmitted force by increasing the distance between the joining surfaces, thereby reducing the diameter and thickness of the insulating plate, and reducing the thickness of the insulating cylinder. Therefore, the thickness of the ring-shaped joint surface can be reduced by reducing the thickness.
Further, it is not necessary to increase the diameter of the metal cylinder, so that a small, inexpensive and highly reliable vacuum valve can be obtained as a whole.

[Brief description of the drawings]

FIGS. 1 and 2 are longitudinal sectional views of a vacuum valve showing first and second embodiments of a coupling member structure according to the present invention, respectively. FIGS. 3 and 4 are different structural examples of a conventional vacuum valve, respectively. FIG. 1: Insulating cylinder (insulator), 2, 12: Coupling member, 3, 13: Fixed contact conductor, 4, 14: Metal disk (coupling member), 5, 15, 25, 26: Shield (coupling member) , 7 : movable contact, 8: bellows, 9, 19:
Metal cylinder, 11,21,31: Insulating plate (insulator).

Claims (1)

(57) [Claims] A rod-shaped fixed contact conductor inserted through a hole provided at the center of a plate-like or cylindrical insulator made of ceramics with a gap therebetween is provided at one of axial end surfaces of said insulator. The fixed contact side of a metal cylinder which is connected to the insulator via a connecting member made of a metal plate and has a joining surface which is joined around the hole and forms a vacuum vessel and has the same potential as the movable contact. A metal having a joint surface on one of the axial end surfaces of the insulator along an outer peripheral edge of the end surface and insulated from the coupling member on the fixed contact conductor side while maintaining insulation. In a vacuum valve coupled to the insulator via a coupling member made of a plate, a coupling surface of the coupling member with the insulator has a coupling end side on a fixed contact conductor side and a coupling end side on a metal cylindrical end side. From the periphery of the joint surface with the insulator Vacuum valve, characterized in that it comprises a cylindrical portion extending in a direction.