KR20120116982A - Vacuum valve - Google Patents

Abstract

<Problem> Obtaining the vacuum valve which can make small the individual difference of the contact resistance which arises by the contact state of a fixed electrode and a movable electrode.
Solution The vacuum valve according to the present invention comprises a vacuum container (1), (2), (3), (8), and a pair of electrodes (5), ( 6) and reinforcing plates 10 and 11 arranged on the back side of the opposing surface to which the pair of electrodes face each other. In addition, the strain absorbing member 5e of the electrode fixed to the electrode and the reinforcing plate is provided between the electrode and the reinforcing plate.

Description

Vacuum valve {VACUUM VALVE}

The present invention relates to a vacuum valve for use in a vacuum circuit breaker.

The vacuum valve is provided with an airtight vacuum vessel, each of which is sealed at both ends of a fixed side end plate and a movable side end plate of an insulating cylinder made of ceramic or glass. The fixed side electrode rod which joined the fixed side electrode is supported and fixed by the end plate, The movable side electrode which moves to the axial direction of an insulating cylinder so that this fixed side electrode opposes is arrange | positioned, The movable side electrode rod is connected to this. The movable electrode and the movable side end plate are hermetically connected through corrugated bellows, and the movable electrode and the movable electrode can be operated while maintaining the vacuum in the vacuum vessel. In addition, an arc is generated between the electrodes during the current interruption, and metal vapor from the electrode is scattered, which causes adhesion to the inner surface of the insulating cylinder and lowers the insulation performance of the inner surface. Therefore, an arc shield is provided around the electrode for the purpose of suppressing contamination of the inner surface of the insulating cylinder.

In the case of performing a large current interruption exceeding several tens of microvolts, an electrode having a spiral structure may be used as one of means for improving the breaking performance. Since the spiral slit was provided in the electrode, an electric current flows in the electrode part (blade part) divided by this slit. The current flows in the circumferential direction along the blade portion to generate a magnetic field in the radial direction, and an arc current in the axial direction is generated between the two electrodes in the magnetic field in the radial direction. Direction of driving force (Lorentz force). As a result, since the arc current rotates in the circumferential direction, localized heating on the surface of the electrode is suppressed, and the breaking performance can be improved.

The blade portion is thin and long in shape, relatively weak in strength, and in the case where the opening and closing operation force is large, deformation of the blade portion occurs, resulting in deterioration in breaking performance or withstand voltage performance. For this reason, a disk-shaped reinforcing plate is fixed to the back of the electrode to increase the rigidity of the blade portion. As a reinforcing plate, austenitic stainless steel, which is a material having high mechanical rigidity and high electrical resistance, is generally used. It adhered to the back surface of an electrode by the construction method (for example, patent document 1).

[Patent Document 1] Japanese Patent Laid-Open No. 9-190744 (3-7 pages, FIGS. 1-9)

In the conventional vacuum valve, since the overall rigidity is increased by the reinforcing plate fixed to the back side of the electrode, the electrode hardly causes partial displacement (bending), and the contact resistance between the fixed side electrode and the movable side electrode is the electrode surface. Since it is determined by the contact area due to the small strain of, there is a problem that individual difference occurs in the contact resistance value due to the contact state between the fixed side electrode and the movable side electrode.

This invention is made | formed in order to solve the said subject, Comprising: It aims at obtaining the vacuum valve which can make small the individual difference of the contact resistance generate | occur | produced by the contact state of a fixed side electrode and a movable side electrode.

The vacuum valve according to the present invention includes a vacuum vessel, a pair of electrodes arranged to be foldable in the vacuum vessel, and a reinforcement plate disposed on the back side of the opposing surface where the pair of electrodes face each other. Equipped with.

In addition, the strain absorbing member of the electrode fixed to the electrode and the reinforcing plate between the electrode and the reinforcing plate is characterized in that it is provided.

According to the vacuum valve according to the present invention, since the deformation absorbing member of the electrode fixed to both is provided between the electrode and the reinforcing plate, the deformation of the electrode is absorbed by compressing or bending the deformation. Since it is possible to bend partially, the electrode can be deformed so as to match the surface shape of the electrode of the counterpart on the fixed side and the movable side. Therefore, it becomes possible to obtain the contact part of several places of an electrode stably, and can make individual difference of a contact resistance small.

1 is a cross-sectional view of a vacuum valve according to Embodiment 1 of the present invention.
2 is an enlarged plan view (a) and an enlarged cross-sectional view (b) of the fixed side electrode of the vacuum valve according to Embodiment 1 of the present invention.
Fig. 3 is a view of projecting the fixed side electrode of the vacuum valve according to the first embodiment of the present invention from the back side.
4 is an enlarged plan view (a) and an enlarged cross-sectional view (b) of a fixed side electrode of the vacuum valve according to Embodiment 2 of the present invention.
5 is a plan view of a ring of a vacuum valve according to Embodiment 2 of the present invention.
6 is a plan view of a ring of a vacuum valve according to Embodiment 2 of the present invention.
7 is a plan view (a) and a DD cross-sectional view (b) of a ring of a vacuum valve according to Embodiment 2 of the present invention.

Embodiment 1

1 is a cross-sectional view of a vacuum valve according to Embodiment 1 of the present invention, FIGS. 2A and 2B are enlarged plan views and enlarged cross-sectional views of the periphery of the fixed side electrode of the vacuum valve, and FIG. 3 is a rear view of the fixed side electrode. The figure projected from the side. In Fig. 1, 1 is an insulating cylinder made of alumina ceramics or the like, 2 is a fixed side end plate covering one end opening of the insulating cylinder 1, and 3 is a movable cover covering the other end opening of the insulating cylinder 1. It is a side end plate, and the fixed side end plate 2 and the movable side end plate 3 are each mounted on the same axis by soldering to the end surface of the insulating cylinder 1, respectively.

4 is a fixed side electrode rod soldered to the fixed side end plate, 5 is a fixed side electrode soldered to the fixed side electrode rod, 6 is a movable side electrode disposed to face the fixed side electrode 5, and 7 is a movable side electrode ( The movable electrode 6, which is soldered and bonded to 6, is a bellows in which the movable electrode 7 is movable in the axial direction of the insulating cylinder 1 while being formed in a corrugated shape of thin stainless steel, for example, to maintain vacuum tightness. to be. The bellows 8 allows the fixed side electrode 5 and the movable side electrode 6 to be folded while maintaining vacuum tightness. The insulating cylinder 1, the fixed side end plate 2, and the movable side end plate (3) and the bellows 8 constitute a vacuum container. The arc shield 9 has a fixed side electrode 5 and a movable side electrode 6 in order to suppress the amount of metal vapor attached to the inner surface of the insulating cylinder 1 due to the arc generated between the electrodes at the time of current interruption. It is arranged to surround the perimeter of.

Reinforcing plates 10 and 11 are respectively disposed on the back side of the opposing surface where the fixed side electrode 5 and the movable side electrode 6 face each other, and the fixed side is provided via a protrusion (deformation absorbing member) 5e to be described in detail later. The solder is bonded to the electrode 5 and the movable electrode 6 and soldered to the fixed electrode 4 and the movable electrode 7. These reinforcing plates 10 and 11 are integrated with the electrodes 5 and 6 to impart proper rigidity to the electrodes 5 and 6, so that when the circuit breaker is introduced, both electrodes 5 and 6 collide with each other. By the force of peeling off the welding during mechanical shock or separation, the electrode is greatly deformed and is prevented from being damaged.

Next, although the structure details of an electrode are demonstrated, since the fixed side electrode 5 and the movable side electrode 6 are symmetric about the surface of the intermediate position of each opposing surface, the fixed side electrode ( 5) will be described only. The outer shape of the fixed side electrode 5 is one of the electrode structures effective for blocking a large current exceeding several tens of microvolts. In this embodiment, as shown in FIG. 2, a spiral shape is employed, and a spiral slit ( By providing 5a), a spiral blade portion 5b is formed. As shown in Fig. 2, since a current flows in the spiral blade portion in the circumferential direction, a magnetic field in the radial direction is generated, and an arc current in the axial direction is generated between the electrodes in the radial magnetic field, thereby causing this arc. The current receives the driving force (Lorentz force) in the circumferential direction. Although it is shown in FIG. 2 that it is a spiral shape, as long as it can flow an electric current in a circumferential direction, it may be another shape, for example, may have a circular shape.

The tip 4 of the fixed side electrode bar 4 is formed with a thin portion 4a, and the hole 11a of the reinforcing plate 11 and the hole 5c of the fixed side electrode 5 are sandwiched therein. Insert and fix by soldering. The fixed side electrode 5 has a shape in which the center portion of the opposite side to the movable side electrode 6 is recessed in a circular shape, and the outer diameter dimension of the fixed side electrode 5 is phi A and the diameter dimension of the central recess portion. ΦB and the diameter dimension of the hole 5c of the fixed side electrode 5 is φC, the contact portion 5d between the fixed side electrode 5 and the movable side electrode 6 is between the size φA and the size φB. It is prescribed | regulated as the area | region of, and dimension (phi) B is made into dimension (phi) C or more.

The step size between the center recessed portion of the fixed side electrode 5 and the contact portion 5d is preferably within 6 mm from the viewpoint of breaking performance. The larger the step, the thicker the electrode 5, the higher the material cost, the lower the magnetic field strength acting on the arc, and consequently the lower the driving force. This is because the speed of rotation in the direction decreases, causing a decrease in the breaking performance.

A projection (deformation absorbing member) 5e is formed on the back side corresponding to the contact portion 5d of the fixed side electrode 5 by lathe machining, and the projection 5e and the reinforcing plate 11 are soldered. It is fixed. When the breaker is turned on, the deformation absorbing member 5e is compressed or bend-deformed by the mechanical impact force caused by the collision between the two electrodes 5 and 6, whereby the blade portion 5b of the electrode 5 It is possible to absorb the strain and partially deflect it.

Moreover, the shape of the projection part 5e, especially the junction area with the reinforcement board 11, or the projection part 5e formed in the one blade part 5b when the electrode 5 is seen from the back side like FIG. As for the cross-sectional area, the electrode 5 is not significantly deformed in response to the load acting between the electrodes 5 and 6 when mounted on the circuit breaker, that is, the mechanical impact force at the time of insertion and the welding force at the time of separation. It must be decided not to. Moreover, since the cross-sectional area of the protrusion 5e when viewed from the back side of the electrode 5 is reduced, the rigidity of the protrusion 5e is reduced and it is easy to deform, so that the electrode 5 due to the bending of the blade portion 5b 5 , 6) can improve the degree of contact between.

As mentioned above, according to the vacuum valve which concerns on this embodiment, since the protrusion part (deformation absorbing member) 5e of the electrode 5 fixed to both was provided between the electrode 5 and the reinforcement board 11, When the breaker is turned on, the deformation absorbing member 5e is compressed or bend-deformed by the mechanical impact force caused by the collision between the two electrodes 5 and 6, whereby the blade portion 5b of the electrode 5 Since the deformation can be absorbed and partially bent, the electrodes 5 can be deformed to match the surface shape of the electrodes of the counterpart on the fixed side and the movable side. Therefore, it is possible to stably obtain a plurality of contact portions over a plurality of blade portions 5b, and the individual difference in contact resistance can be reduced.

In addition, the electron repelling force between the electrodes 5 and 6 increases in proportion to the approximately square of the conduction current, so that the contact points can be increased by making it easy to harmonize between the electrodes 5 and 6 as shown above. Since the current flow can be divided, it is possible to reduce the electron repelling force between the two electrodes, thereby suppressing the arcing phenomenon. As a result, it is possible to reduce the force for removing the welding after short-time high current energization or after high current input, thereby simplifying and miniaturizing the operation mechanism and operation force transmission mechanism of the circuit breaker.

Moreover, according to the vacuum valve which concerns on this embodiment, since the projection part (deformation absorbing member) 5e is provided in the back side corresponding to the contact part 5d, it receives the compression force by the mechanical shock at the time of circuit breaker injection directly. As a result, the protrusion (deformation absorbing member) 5e is more likely to be compressed, and the blade portion 5b of the electrode is more easily matched to the shape of the movable electrode 6 of the counterpart more faithfully. Individual difference can be made small.

Moreover, since the protrusion part (deformation absorbing member) 5e is formed in the back side of the electrode 5, it can be processed easily and cheaply by lathe etc., and is integrally formed with the electrode 5, As a result, the number of parts can be reduced.

In addition, about the above-mentioned effect, although it can obtain even if it is provided in the back side of either the fixed side electrode 5 or the movable side electrode 6, the one provided in the back side of both electrodes complements the deformation | transformation of both electrodes. Since it is possible to improve the roughness to the counter electrode, the higher effect can be obtained.

Embodiment 2 Fig.

4 (a) and 4 (b) are enlarged plan views and enlarged cross-sectional views of the periphery of the fixed side electrode of the vacuum valve according to Embodiment 2 of the present invention. Since the vacuum valve concerning this embodiment is the same as that of Embodiment 1 except the components around an electrode, the description other than this part is abbreviate | omitted. In Embodiment 1, although the protrusion part 5e was formed in the back side of the contact part 5d of the stationary side electrode 5, in this embodiment, the ring 12 of the member separate from the stationary side electrode 5 is formed. The difference between the fixed side electrode 5 and the reinforcing plate 11 between the fixed side electrode 5 is different.

By setting it as a member separate from the fixed side electrode 5, it becomes possible to select arbitrary materials according to the rigidity required. As the reinforcing plate 11, austenitic stainless steel is generally used as the material of the electrodes 5 and 6, but a copper chromium alloy is generally used, but it is also less rigid than these materials. For example, oxygen-free copper may be used. This makes it possible to faithfully harmonize the blade portion 5b of the electrode 5 by the surface shape of the counter electrode.

As a shape of the ring 12, the normal ring 12a shown in FIG. 5 is preferable from a viewpoint of granulation property and manufacturability. However, if the thing having the shape of 12a is fixed to the back side of the electrodes 5 and 6 by soldering, the adjacent blade portions 5b separated by the slit 5a having a spiral shape are connected to the ring 12a. ), The leakage current passing through the adjacent blade portion 5b becomes large, resulting in a decrease in the current value flowing in the blade portion 5b in the circumferential direction and a decrease in the magnetic field based thereon, thereby driving force against the arc. This deterioration becomes a problem.

So, using the ring 12b shown in FIG. 6, the back side of the blade part 5b is the same width as the ring 12a, but the back side of the slit part 5a forms the part 12c narrower than that. By increasing the resistance value of the portion, it is possible to reduce the leakage current passing through the adjacent blade portion 5b and to improve the breaking performance. Or like the ring 12d shown in FIG. 7, the back side of the slit part 5a has the resistance value of the 12e part similarly, even if it has 12e (refer to DD of FIG. 7B) formed so that thickness may become thin. Since it can raise, leakage current can be made small and it can contribute to the improvement of breaking performance.

Ideally, if an arc-shaped part is used only on the back side of the blade part, which is divided in the circumferential direction, the part score increases, but it is possible to maximize the resistance value between the adjacent blade parts 5b. . In any of the above cases, in order to improve assembly workability, a step for positioning with the rings 12a, 12b, and 12d may be formed on one or both sides of the fixed side electrode 5 or the reinforcing plate 11.

As described above, according to the vacuum valve according to the present embodiment, since the ring (strain absorbing member) 12 fixed to both is provided between the electrode 5 and the reinforcing plate 11, By compressing or bending deformation of the deformation absorbing member 12 by mechanical impact force caused by the collision between the two electrodes 5, 6, the deformation of the blade portion 5b of the electrode 5 is absorbed, Since it becomes possible to bend partially, the electrode 5 can be deformed so that it may harmonize with the surface shape of the electrode of the counterpart on the fixed side and the movable side. Therefore, it is possible to stably obtain a plurality of contact portions over a plurality of blade portions 5b, and the individual difference in contact resistance can be reduced.

In addition, the electron repelling force between the electrodes 5 and 6 increases in proportion to the approximately square of the conduction current, so that the contact points can be increased by making it easy to harmonize between the electrodes 5 and 6 as shown above. Since the electric current can be classified, it is possible to reduce the electron repelling force between the two electrodes, thereby suppressing the arcing phenomenon. As a result, it is possible to reduce the force for removing the welding after short-time high current energization or after high current input, so that the operation mechanism of the circuit breaker and the operation force transmission mechanism can be simplified and downsized.

Further, according to the vacuum valve according to the present embodiment, the ring (deformation absorbing member) 12 is provided on the back side corresponding to the contact portion 5d, so that the compressive force due to the mechanical shock when the breaker is inserted is directly received. Therefore, the ring (deformation absorbing member) 12 tends to be compressed and the blade portion 5b of the electrode is more easily matched to the shape of the movable side electrode 6 of the other party, so that the object of contact resistance is further increased. The car can be made small.

According to the vacuum valve according to the present embodiment, since the ring (deformation absorbing member) 12 is configured as a member separate from the electrode 5, it is possible to select any material according to the rigidity required. This has the advantage of improving design freedom.

The rings (strain absorbing members) 12b and 12d have a narrow portion 12c or a thin portion 12e formed on the back side of the slit 5a, and the blade portion 5b of the electrode 5. ) And the resistance value of the non-fixed portion are larger than the resistance values of the blade portion 5b and the fixed portion, so that the leakage current passing through the adjacent blade portion 5b can be reduced to act on the arc current. By suppressing the driving force drop, the breaking performance can be improved.

1 Insulation cylinder 2 Fixed side end plate
3 Movable Side End Plate 5 Fixed Side Electrode
5a slit 5b blade part
5d contact 5e protrusion (deformation absorbing member)
6 movable side electrode 8 bellows
10 Gusset 11 Gusset
12 rings (strain absorbing members) 12a rings (strain absorbing members)
12b ring (deformation absorbing member) 12c narrow part
12d ring 12e thin section

Claims (5)

Vacuum container,
A pair of electrodes disposed in the vacuum vessel so as to be opposed to each other;
A reinforcing plate disposed on the back side of the opposing surface to which the pair of electrodes face each other,
And a strain absorbing member of the electrode fixed to the electrode and the reinforcing plate between the electrode and the reinforcing plate. The method according to claim 1,
Electrode has a spiral (spiral) or circular shape of the electrode is provided with a slit blade portion (blade) extending in the circumferential direction is formed, characterized in that the vacuum valve. The method according to claim 1 or 2,
The electrode has a contact portion that the pair of electrodes contact,
The deformation absorbing member is a vacuum valve, characterized in that provided on the back side corresponding to the contact portion. The method according to claim 1 or 2,
The deformation absorbing member is a vacuum valve, characterized in that the projection formed on the back side of the electrode. The method according to claim 2,
The deformation absorbing member has a ring shape, and the resistance value of the blade portion and the portion not fixed to the electrode is larger than the resistance value of the blade portion and the fixed portion of the vacuum valve.

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