VACUUM INTERRUPTER FOR A VACUUM CIRCUIT BREAKER

Abstract

A vacuum interrupter for a vacuum circuit breaker is disclosed, in which a center shield is arranged between an upper insulating envelope and a lower insulating envelope, whereby the center shield is not provided inside each of the insulating envelopes and thus outer diameters of the respective insulating envelopes are reduced.

Claims

1. A vacuum interrupter for a vacuum circuit breaker, comprising: an upper insulating envelope; a lower insulating envelope arranged below the upper insulating envelope; a fixed electrode portion installed to be fixed to the inside of the upper insulating envelope; an actuating electrode portion installed inside the lower insulating envelope to face the fixed electrode portion and to be in contact with or detached from the fixed electrode portion; and a center shield arranged between the upper insulating envelope and the lower insulating envelope, receiving the fixed electrode portion and the actuating electrode portion.

2. The vacuum interrupter for a vacuum circuit breaker according to claim 1, further comprising a first auxiliary shield provided inside the upper insulating envelope and the lower insulating envelope.

3. The vacuum interrupter for a vacuum circuit breaker according to claim 1, wherein the center shield has an outer diameter the same as or greater than an inner diameter of each of the upper insulating envelope and the lower insulating envelope.

4. The vacuum interrupter for a vacuum circuit breaker according to claim 1, wherein a fixed electrode is formed at one end of the fixed electrode portion, an actuating electrode, which is in contact with or detached from the fixed electrode, is formed at one end of the actuating electrode portion, and the center shield has an inner diameter greater than a sum of an outer diameter of the fixed electrode or the actuating electrode and a distance between the respective electrodes.

5. The vacuum interrupter for a vacuum circuit breaker according to claim 2, wherein the first auxiliary shield is provided with a fixed portion, the upper insulating envelope includes a first upper envelope and a second upper envelope arranged below the first upper envelope to allow the fixed portion to be fitted between the first upper envelope and the second upper envelope, and the lower insulating envelope includes a first lower envelope and a second lower envelope arranged below the first lower envelope to allow the fixed portion to be fitted between the first lower envelope and the second lower envelope.

6. The vacuum interrupter for a vacuum circuit breaker according to claim 5, wherein upper and lower lengths of the first upper envelope and the second lower envelope are the same as those of the second upper envelope and the first lower envelope.

7. The vacuum interrupter for a vacuum circuit breaker according to claim 2, wherein a second auxiliary shield is formed respectively between the upper insulating envelope and the center shield and between the lower insulating envelope and the center shield.

8. The vacuum interrupter for a vacuum circuit breaker according to claim 7, wherein the second auxiliary shield is provided with a protrusion which is formed to be outwardly protruded.

9. The vacuum interrupter for a vacuum circuit breaker according to claim 8, wherein the protrusion is formed in a single body with the second auxiliary shield or connected with the second auxiliary shield through welding.

10. The vacuum interrupter for a vacuum circuit breaker according to claim 8, wherein the protrusion has one end formed to be inwardly bent in a circular shape or curved shape.

11. The vacuum interrupter for a vacuum circuit breaker according to claim 1, wherein a flange is provided above the upper insulating envelope and below the lower insulating envelope to seal the insides of the upper insulating envelope and the lower insulating envelope.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments and together with the description serve to explain the principles of the invention.

[0030] In the drawings:

[0031] FIG. 1 is a cross-sectional view illustrating a vacuum interrupter provided in a vacuum circuit breaker of the related art;

[0032] FIG. 2 is a cross-sectional view illustrating a vacuum interrupter provided in a vacuum circuit breaker according to one embodiment of the present invention;

[0033] FIG. 3 is a cross-sectional view illustrating a vacuum interrupter provided in a vacuum circuit breaker according to another embodiment of the present invention; and

[0034] FIG. 4 is a partially enlarged view illustrating a second auxiliary shield of a vacuum interrupter provided in a vacuum circuit breaker according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0035] Hereinafter, a vacuum interrupter provided in a vacuum circuit breaker according to one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0036] FIG. 2 is a cross-sectional view illustrating a vacuum interrupter provided in a vacuum circuit breaker according to the present invention, FIG. 3 is a cross-sectional view illustrating a vacuum interrupter provided in a vacuum circuit breaker according to another embodiment of the present invention, and FIG. 4 is a partially enlarged view illustrating a second auxiliary shield of a vacuum interrupter provided in a vacuum circuit breaker according to the present invention.

[0037] As shown in FIGS. 2 and 3, a vacuum interrupter 100 for a vacuum circuit breaker according to the present invention includes an upper insulating envelope 111, a lower insulating envelope 113, a fixed electrode portion 115, an actuating electrode portion 117, a center shield 119, and a first auxiliary shield 121.

[0038] The upper insulating envelope 111 is made of ceramic or reinforced glass, and constitutes upper side enclosure such that the fixed electrode portion 115 is arranged inside the upper insulating envelope 111.

[0039] The lower insulating envelope 113 is made of ceramic or reinforced glass, and constitutes lower side enclosure such that the actuating electrode portion 117 is arranged inside the lower insulating envelope 113.

[0040] The fixed electrode portion 115 is provided inside the upper insulating envelope 111, and includes a fixed electrode 115a at one end thereof and thus is in contact with or detached from the actuating electrode portion 117 in accordance with movement of the actuating electrode portion 117.

[0041] The actuating electrode portion 117 is installed inside the lower insulating envelope 113 to face the fixed electrode portion 115, and includes an actuating electrode 117a at one end thereof and thus is in contact with or detached from the fixed electrode portion 115 in accordance with up and down movement.

[0042] The center shield 119 is used so that metal steam generated during current breaking is not deposited on an inner wall of each insulating envelope 111, 113, and is made of stainless steel or Cu and arranged between the upper insulating envelope 111 and the lower insulating envelope 113.

[0043] Also, the center shield 119 is connected to each of one end and the other end of the upper insulating envelope 111 and the lower insulating envelope 113 through welding such as blazing, and constitutes enclosure of a center to receive the fixed electrode portion 115 and the actuating electrode portion 117 therein.

[0044] At this time, the center shield 119 is not provided inside each insulating envelope 111, 113 but arranged between the upper insulating envelope 111 and the lower insulating envelope 113, whereby an inner diameter of each insulating envelope 111, 113 becomes smaller.

[0045] Meanwhile, an outer diameter D1 of the center shield 119 is formed to be the same as or greater than inner diameters D2 and D2 of the upper insulating envelope 111 and the lower insulating envelope 113.

[0046] Also, since the center shield 119 has a thickness thinner than that of each of the upper insulating envelope 111 and the lower insulating envelope 113, the diameter D1 of the center shield 119 is formed to be smaller than an outer diameter (not shown) of each of the upper insulating envelope 111 and the lower insulating envelope 113. However, without limitation to the above example, the outer diameter D1 of the center shield 119 may be formed to be greater than the outer diameter of each of the upper insulating envelope 111 and the lower insulating envelope 113.

[0047] Also, an inner diameter of the center shield 119 is formed to be greater than a sum of an outer diameter D4 of the fixed electrode 115a or the actuating electrode 117a and a distance D5 between the respective electrodes, whereby the center shield 119 is sufficiently spaced apart from each of the electrodes 115a and 117a. As a result, the current is prevented from entering the actuating electrode 117a through the center shield 119 from the fixed electrode 115a and thus breakdown of insulation is prevented from occurring in the vacuum interrupter 100.

[0048] The first auxiliary shield 121 is provided respectively inside each of the upper insulating envelope 111 and the lower insulating envelope 113.

[0049] Meanwhile, the first auxiliary shield 121 is provided with a fixed portion 121a formed to be fitted between a first upper envelope 111a and a second upper envelope 111b or between a first lower envelope 113a and a second lower envelope 113b, which will be described later.

[0050] Also, the upper insulating envelope 111 includes the first upper envelope 111a, and the second upper envelope 111b arranged below the first upper envelope 111a. As the fixed portion 121a is fitted between the first upper envelope 111a and the second upper envelope 111b, the first auxiliary shield 121 is arranged to be tightly adhered to the upper insulating envelope 111.

[0051] In addition, the lower insulating envelope 113 includes the first lower envelope 113a, and the second lower envelope 113b arranged below the first lower envelope 113a. As the fixed portion 121a is fitted between the first lower envelope 113a and the second lower envelope 113b, the first auxiliary shield 121 is arranged inside the lower insulating envelope 113.

[0052] At this time, upper and lower lengths L1 and L4 of the first upper envelope 111a and the second lower envelope 113b are formed to be the same as each other, and upper and lower lengths L2 and L3 of the second upper envelope 111 b and the first lower envelope 113a are also formed to be the same as each other.

[0053] Therefore, symmetricity of the respective envelopes constituting enclosure of the vacuum interrupter 100 is improved, whereby insulating performance of the vacuum interrupter 100 is maintained.

[0054] That is, since a voltage for applying a current may be applied to an upper side where the first upper envelope 111a and the second upper envelope 111 b are arranged or a lower side where the first lower envelope 113a and the second lower envelope 113b are arranged, the respective upper envelopes 111a and 111b and the respective lower envelopes 113a and 113b corresponding to the respective upper envelopes 111a and 111b are formed to have the same size having insulating performance suitable for the applied voltage, whereby insulating performance is maintained uniformly regardless of the fact that the voltage is applied to the upper side or the lower side.

[0055] Meanwhile, a second auxiliary shield 123 is formed respectively between the upper insulating envelope 111 and the center shield 119 and between the lower insulating envelope 113 and the center shield 119.

[0056] As shown in FIG. 4, the second auxiliary shield 123 is provided with a protrusion 123a formed to be protruded toward the outside, wherein one end of the protrusion 123a is bent inwardly in a circular shape or curved shape. ?

[0057] At this time, the protrusion 123a may be formed in a single body with the second auxiliary shield 123, or may be manufactured separately to be mutually connected with the second auxiliary shield 123 through welding.

[0058] Therefore, since one end of the protrusion 123a is bent and formed in a circular shape or curved shape, concentration of electric field is prevented from occurring at a junction area of the center shield 119, the upper insulating envelope 111 and the lower insulating envelope 113, that is, a junction area through brazing welding, whereby partial discharge or breakdown of insulation is prevented from occurring at the junction area.

[0059] In addition, a flange 130 is provided above the upper insulating envelope 111 and below the lower insulating envelope 113, whereby the upper end of the upper insulating envelope 111 and the lower end of the lower insulating envelope 113 are blocked by the flange 130 and thus their insides are sealed.

[0060] The vacuum interrupter 100 for a vacuum circuit breaker according to the present invention, which is configured and operated as above, allows the center shield 119 to be arranged between the upper insulating envelope 111 and the lower insulating envelope 113, whereby upper and lower lengths of the respective insulating envelopes 111 and 113 are reduced.

[0061] Also, the center shield 119 is arranged between the upper insulating envelope 111 and the lower insulating envelope 113, whereby the center shield 119 is not provided inside each of the insulating envelopes 111 and 113 and thus outer diameters of the respective insulating envelopes 111 and 113 are reduced.

[0062] Also, as the upper and lower lengths and the outer diameters of the insulating envelopes 111 and 113 are reduced, a full size of the insulating envelopes 111 and 113 is reduced, whereby the amount of ceramic used to manufacture the insulating envelopes 111 and 113 is reduced and thus the manufacturing cost is saved remarkably.

[0063] Also, as the second auxiliary shield 123 is provided with the protrusion 123a and one end of the protrusion 123a is bent to be formed in a circular shape or curved shape, concentration of electric field is prevented from occurring at the junction area of the center shield 119, the upper insulating envelope 111 and the lower insulating envelope 113, that is, the junction area through brazing welding, whereby partial discharge or breakdown of insulation is prevented from occurring at the junction area.

[0064] The foregoing embodiments and advantages are merely exemplary and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.

[0065] As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.