JP3840935B2 - Vacuum interrupter contacts and vacuum interrupters - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a contact of a vacuum interrupter and a vacuum interrupter using the same.
[0002]
[Prior art]
In order to improve the interruption performance of the vacuum interrupter, it is necessary to catch the arc on the entire electrode surface without concentrating the arc generated between the electrodes at the time of interruption. A structure (vertical magnetic field application method) in which a vertical magnetic field is formed between the electrodes is adopted as a means for receiving an arc on the entire electrode surface. By generating a longitudinal magnetic field between the electrodes, the arc is confined by the magnetic field, the loss of charged particles from the arc column is reduced, the arc is stabilized, the temperature rise of the electrode part is suppressed, and the interruption performance is improved.
[0003]
Japanese Patent Publication No. 3-59531 discloses “a contact device for a vacuum switch” as an example of a method using a longitudinal magnetic field application method. This is a slit formed on the peripheral surface of a hollow cylindrical contact base provided with a contact plate on the end face. The depth of the contact base (the depth of the pot), the number of slits, The azimuth angle of the slit is specified.
[0004]
[Problems to be solved by the invention]
In a vacuum interrupter, in order to obtain a high-voltage, high-current interruption performance, it is necessary to increase the diameter of the contact and to increase the distance (dissociation distance) between the opposing contacts. However, in the one described in Japanese Patent Publication No. 3-59531, when the contact diameter and dissociation distance are set in this way, the magnetic flux density between the electrodes becomes insufficient, the arc between the electrodes becomes unstable, and cannot be interrupted. .
[0005]
Further, if the azimuth angle of the slit formed in the contact base is increased in order to secure the generated magnetic field, the strength of the contact itself is insufficient, and the withstand voltage performance and the breaking performance are deteriorated due to deformation due to the opening / closing operation force.
[0006]
[Means for Solving the Problems]
The contact of the vacuum interrupter according to the first aspect of the present invention for solving the above-mentioned problem is that the contact plate is provided on the end surface of the contact table, and the coil portion is formed by forming a slit in the peripheral surface of the contact table. In a contact of a vacuum interrupter configured to form a longitudinal magnetic field along the axial direction of the contact table by a current flowing through the contact portion, a circumferential slit portion formed on the surface of the end surface of the contact table and its end And a second slit formed by inclining with respect to the axis of the contact base from the middle of the contact base in the axial direction. It consisted of a slit, wherein the first slit and the second slit, the predetermined range overlap at the contact carrier axis, said contact plate is linear slit Characterized in that it is formed.
[0007]
A contact of a vacuum interrupter according to a second aspect of the present invention that solves the above problem is the contact of the vacuum interrupter according to the first aspect of the present invention, wherein the second slit opens to the other end surface of the contact base. It is characterized by that.
[0008]
The contact of the vacuum interrupter according to a third aspect of the present invention that solves the above problem is the contact of the vacuum interrupter according to the first or second aspect of the invention,
The outer diameter D of the contact table is
60mm ≦ D ≦ 200mm
When
For the outer diameter D of the contact table, the length L of the contact table and the number S of the slits are:
0.2 D ≦ L ≦ D
0.1D / mm ≦ S ≦ 0.2D / mm
And
An inclination angle α with respect to the axis of the contact base of the inclined slit portion and the second slit of the first slit is,
60 ° ≦ α ≦ 80 °
And
The azimuth angle β of the inclined slit portion and the second slit in the first slit is:
(540 / S) ° ≦ β ≦ (1440 / S) °
And
An azimuth angle γ between the inclined slit portion of the first slit and the second slit is:
(120 / S) ° ≦ γ ≦ (600 / S) °
And
The azimuth angle δ of the circumferential slit portion of the first slit is:
(120 / S) ° ≦ δ ≦ (600 / S) °
It is characterized by being prescribed | regulated.
[0009]
In the contact of this vacuum interrupter, the coil portion is between the first slits, between the first slit and the second slit, and between the second slits. A current flows through these coil portions as a path, and generates a magnetic field.
In addition, since there is a circumferential slit portion on the end surface of the contact table, the current flows between the first slits after turning in the circumferential direction by the contact plate. Since the current path becomes longer, a stronger magnetic field is generated.
Furthermore, a solid pillar portion is formed between the inclined slit portion of the first slit and the second slit, and this portion reinforces the contact table.
[0010]
A contactor of a vacuum interrupter according to a fourth aspect of the present invention that solves the above-described problem is the contactor of the vacuum interrupter according to the third aspect of the invention, wherein the plate thickness W of the contact base is defined as 6 mm ≦ W ≦ 12 mm. It is characterized by that.
[0011]
A vacuum interrupter according to a fifth aspect of the present invention that solves the above-described problem is arranged such that the contacts of the vacuum interrupters according to the first to fourth aspects of the present invention face each other on the same axis, and the distance G between the facing contacts is set. 15 mm ≦ G ≦ 100 mm.
[0012]
In each of the above inventions, a reinforcing body is provided on the bottom surface or the end plate in the contact table. The contact plate is joined to the end face of the reinforcing body, and the reinforcing body prevents deformation of the contact plate and the contact table. For example, a cylindrical body is used as the reinforcing body.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the vacuum interrupter and the contact of the vacuum interrupter according to the present invention will be described with reference to the drawings.
FIG. 1 shows a side surface of a contact of a vacuum interrupter according to an embodiment, and FIG. 2 shows a plane thereof. FIG. 3 shows azimuth angles, and FIGS. 4 and 5 show contacts facing each other as a vacuum interrupter.
[0014]
The contact table 1 has a cylindrical shape, and a contact plate 2 is brazed to one end surface 1a, and a contact end plate 3 to which a lead bar is connected is brazed to the other end surface 1b of the contact table 1. The In this example, a ring-like fitting portion 3b is formed on the surface 3a of the contactor end plate 3, and this ring-like fitting portion 3b is fitted inside the hollow cylindrical contact table 1 and brazed. Has been. One end of a cylindrical reinforcing body 4 is fitted inside the fitting portion 3 b of the contact end plate 3. The contact plate 2 attached to the end surface 1a of the contact table 1 by brazing is in contact with the end surface of the reinforcing body 4 and brazed. That is, the cylindrical reinforcing body 4 reinforces the contact plate 2 and the contact table 1 and prevents these deformations. In addition, since the cylindrical contact stand 1 and the contact end plate 3 form a cup shape, such a contact is called a cup shape.
[0015]
The diameter D of the contact table 1 is selected in the range of 60 mm ≦ D ≦ 200 mm according to the cutoff current and voltage. This range is based on the result of the current interruption test. The length (crucible depth) L of the contact table 1 is set in the range of 0.2 D ≦ L ≦ D. This is determined based on an inclination angle α and an azimuth angle β described later. Further, the thickness (wall thickness) W of the contact table 1 is set in a range of 6 mm ≦ W ≦ 12 mm. This is a range determined in consideration of strength and the like. In the example shown in FIG. 1, the thickness of the contact table 1 is uniform over the entire length, but in the sense of reinforcement, the thickness varies within the range of 6 mm ≦ W ≦ 12 mm as shown in FIG. May be attached.
[0016]
A first slit 5 and a second slit 6 are formed on the cup-shaped contact base 1. The first slit 5 is connected to the circumferential slit portion 5a formed in the circumferential direction on the end surface 1a of the contact table 1 and the end of the circumferential slit portion 5a, and is angled with respect to the axis of the contact table 1 ((inclination angle ) It is composed of an inclined slit portion 5b formed on the peripheral surface of the contact table 1 by inclining α, and the second slit 6 extends from the other end surface 1b of the contact table 1 to the middle of the contact table 1 in the axial direction. are formed to. that is, the second slit 6, in. view opens into the end face 1b, 6a is at its opening. the first inclined slit portion 5 b and the slit 5 which forms the arc The azimuth angle β, which is the opening angle of the slit 6 of the second slit with respect to the center O of the contact table 1, is constant, and the portion sandwiched between the slit portion 5 b and the slit 6 becomes a coil portion. sandwiched between the first inclined slit portion 5 b of the slit 5 Min coil portion 7a, the coil portion of the coil portion 7b, sandwiched between the second slit 6 adjacent portion of the inclined slit portion 5 b and a portion held and the second slit 6 of the first slit 5 7c is formed.
[0017]
The total number of the first slit 5 (inclined slit portion 5 b ) and the second slit 6 is set in a range of 0.1 D / mm ≦ S ≦ 0.2 D / mm. Accordingly, the first and second slits 5 and 6 are half the number of S. The inclination angle α of the inclined slit portion 5a of the first slit 5 and the second slit 6 is set in a range of 60 ° ≦ α ≦ 80 °. This is a range determined based on the mechanical strength and resistance reduction of the contact table 1. That is, in order to reduce the mechanical strength and resistance of the contact table 1, the distance x between the adjacent slits 5, the slits 6 or the slits 5 and 6 in the direction perpendicular to them is preferably about 7 to 18 mm. Then, from the diameter D of the contact table 1 and the number S of slits, the range of the inclination angle α is 60 ° ≦ α ≦ 80 °.
[0018]
Azimuth beta of the first inclined slit 5 slit portion 5 b and the second slit 6 is set in the range of (540 / S) ° ≦ β ≦ (1440 / S) °. The reason why the lower limit value is (540 / S) ° is that the length of the coil portion is 1.5 turns, and below this, the magnetic flux is insufficient. The upper limit is set to (1440 / S) ° because the length of the coil portion is 4 turns, and if it is more than this, the resistance increases and a problem due to heat generation occurs. Further, the mechanical strength of the contact table 1 is lowered.
The azimuth angle δ of the circumferential slit portion 5a of the first slit 5 is set in the range of (120 / S) ° ≦ γ ≦ (600 / S) °. This is determined in terms of the mechanical strength of the contact table 1.
[0019]
Both the first slit 5 and the second slit 6 are formed at equal intervals. The inclined slit portion 5 b of the first slit 5 and second slit 6, in the circumferential direction are formed spaced a predetermined distance (azimuth) gamma. This azimuth angle γ is set in the range of (120 / S) ° ≦ γ ≦ (600 / S) °. This range is determined from the point of mechanical strength of the contact table 1.
[0020]
The length of the first inclined slit 5 slit portion 5 b and the second slit 6 by shortening the interval between the inclined slit portion 5 b and the second slit 6 in the circumferential direction (azimuth gamma) is Since it was made possible, a solid column portion 1c is formed between the inclined slit portion 5b and the second slit 6. The strength of the contact table 1 is maintained by the column portion 1c. That is, if a long slit is provided in the circumferential direction, the axial strength of the contact table 1 is weakened. However, the axial strength of the contact table 1 is maintained by forming the column portion 1c in this way. It is.
[0021]
The inclined slit portion 5 b of the first slit 5 and the second slit 6 overlap with each other in a predetermined range in the axial direction of the contact table 1. The second slit 6 may be formed as desired between the inclined slit portions 5 b of the two adjacent first slits 5. As shown in FIG. 2, the contact plate 2 is formed with a linear slit 8. The number of slits 8 is the same as the number of first slits 5. The extension on the inner side of the slit 8 is deviated from the center O of the contact plate 2 and forms a spiral as a whole as shown in FIG. The contact plate 2 has an end 8a on the circumferential surface side of the slit 8 aligned with an end of the circumferential slit portion 5a of the first slit 5 on the opposite side to the side where the inclined slit portion 5b is connected. Installed. That is, the slit 8 and the first slit 5 are connected.
[0022]
In the above embodiment, the contact end plate 3 is joined to the other end side of the contact base 1, but a portion corresponding to the contact end plate 3 is formed integrally with the contact base 1. It can also be left as a cup. In that case, for example, the second slit 6 is formed with a position corresponding to the inner bottom surface of the contact table 1 as a reference position. The depth of the cup-shaped integrated product (the depth of the pot) corresponds to the length L of the contact base 1. In the above embodiment, only the first slit 5 includes the circumferential slit portion 5 a and the inclined slit portion 5 b. However, the second slit 6 may also be composed of a circumferential slit portion and an inclined slit. In this case, the circumferential slit portion is formed on the other end surface 1 b of the contact table 1.
[0023]
FIG. 6 schematically shows a vacuum interrupter configured using the vacuum interrupter contact configured as described above. The vacuum contactors 11 and 12 of the two vacuum interrupters having the structure shown in FIGS. 1 to 3 are coaxially opposed to each other with a predetermined gap (distance between the contacts) G as shown in FIGS. The vacuum interrupter 10 is configured by being placed in the container 13. The inter-contact distance G is set in a range of 15 mm ≦ G ≦ 100 mm.
[0024]
The vacuum vessel 13 is configured by closing both ends of an insulating cylinder 14 made of ceramic or glass with end plates 15 and 16 made of metal and exhausting the inside to a high vacuum. One contactor 11 is fixed as a fixed electrode to the tip of a fixed rod 17 fixed through one end plate 15 of the vacuum vessel 13. The other contact 12 is fixed as a movable electrode through the other end plate 16 of the vacuum vessel 13 and at the tip of a movable rod 19 movably provided by a bellows 18. In the vacuum vessel 13, a shield 20 is provided around the contacts 11 and 12.
[0025]
In the vacuum interrupter having the above-described configuration, an arc is generated between the contacts 11 and 12 as electrodes when the current is interrupted. On the other hand, since the current i has a circumferential slit portion 5 a that is an insulating layer between the contact plate 3 and the contact table 1, the current i swivels along the contact plate 3 and then the inclined slit portion 5 of the contact table 1. b enters the coil portion 7 a between b , and further flows into the coil portion 7 b between the inclined slit portion 5 b of the first slit 5 and the second slit 6 and the coil portion 7 c between the second slit 6. A current flows through the coil portions 7a, 7b, and 7c, and a longitudinal magnetic field B is generated between the contact plates 2. Since there are many current paths and a long path can be secured, it is possible to form a magnetic field twice or more that of the first slit 5 alone. Therefore, the arc can be stabilized and good interruption performance can be obtained.
[0026]
Next, examples of the vacuum interrupter contact and the vacuum interrupter having the above-described configuration will be described. The dimensions of each part of the contacts 11 and 12 were defined as follows to produce a vacuum interrupter.
Outer diameter D = 80 mm of the contact carrier 1, a length L = 27 mm contact carrier 1, the number of slits S = 12 (one side 6), the inclination of the inclined slit portion 5 b and the second slit 6 of the first slit 5 The angle α = 70 °, the azimuth angle β of the inclined slit portion 5 b and the second slit 6 of the first slit 5 = 65 °, and the inclination slit portion 5 b of the first slit 5 and the second slit 6. The azimuth angle γ = 30 ° of the intermediate portion, the azimuth angle δ = 15 ° of the circumferential slit 5a, and the wall thickness W of the contact table W = 8.5 mm
[0027]
In this vacuum interrupter, the magnetic flux density generated at the center when the contacts 11 and 12 are arranged to face each other at a distance of 40 mm (distance G between contacts) on the same axis is 4.2 μT / A. With this vacuum interrupter, a breaking performance of a rated voltage of 72 kV and a rated breaking current of 31.5 kA was achieved.
[0028]
As another example, a vacuum interrupter having the following dimensions was manufactured.
The outer diameter D of the contact table 1 is 90 mm, the length L of the contact table 1 is 37 mm, the number of slits S is 12 (one side 6), the inclined slit portion 5 b of the first slit 5 and the inclination of the second slit 6. The angle α = 72 °, the azimuth angle β of the inclined slit portion 5 b of the first slit 5 and the second slit 6 β = 75 °, the inclined slit portion 5 b of the first slit 5 and the second slit 6. Azimuth angle γ = 13 ° between the portions, each azimuth δ = 20 ° of the circumferential slit portion 5a, wall thickness W = 8.5 mm of the contact table
[0029]
In this vacuum interrupter, the magnetic flux density generated at the center when the contacts 11 and 12 are arranged to face each other at a distance of 40 mm (distance G between contacts) on the same axis is 4.5 μT / A. With this vacuum interrupter, a breaking performance of a rated voltage of 72 kV and a rated breaking current of 40 kA was achieved.
[0030]
【The invention's effect】
According to the contactor and the vacuum interrupter of the vacuum interrupter according to the present invention, a contact plate is provided on the end surface of the cup-shaped contact base, and a coil portion is formed by forming a slit on the peripheral surface of the contact base. In a contact of a vacuum interrupter configured to form a longitudinal magnetic field along the axial direction of the contact table by a current flowing through the contact portion, a circumferential slit portion formed on the surface of the end surface of the contact table and its end And a second slit formed to be inclined with respect to the axis of the contact table from the middle of the contact table in the axial direction. It consisted of a slit, wherein the first slit and the second slit, the predetermined range overlap at the contact carrier axis, said contact plate is linear By slits are formed, and the second slit, by which is open on the other end face of the contact carrier, the vacuum interrupter prepared using contacts of the vacuum interrupter is produced between the contacts The intensity of the magnetic field to be generated can be increased, the arc generated at the time of interruption can be evenly distributed, and the interruption performance can be improved.
[0031]
According to the contactor and vacuum interrupter of the vacuum interrupter according to the present invention, when the outer diameter D of the contact table is 60 mm ≦ D ≦ 200 mm, the length of the contact table is larger than the outer diameter D of the contact table. L, the number S of the slits is defined as 0.1 D ≦ L ≦ D , 0.1 D / mm ≦ S ≦ 0.2 D / mm, and the inclination angle α of each slit with respect to the axis of the contact table is defined as 60 ° ≦ α ≦ 80 °, the azimuth angle β of each slit is defined as (540 / S) ° ≦ β ≦ (1440 / S) °, and the azimuth angle between the first and second slits γ is defined as (120 / S) ° ≦ γ ≦ (600 / S) °, and the azimuth angle δ of the circumferential slit portion of the first slit is (120 / S) ° ≦ δ ≦ (600 / S) In the vacuum interrupter manufactured using this vacuum interrupter contact, the contact between the contacts Make it possible to increase the green magnetic field strength, uniformly distributed arc generated at the time of cut-off, it is possible to improve the breaking performance.
[0032]
In particular, in order to ensure the high-voltage, high-current interrupting performance, the magnetic field strength generated between the contacts must be sufficiently and sufficient when the contact diameter is large and the dissociation distance (distance between the contacts) must be increased. It can be increased, and a stable shut-off performance can be achieved.
[0033]
Further, in the circumferential direction, a solid column portion is formed between the inclined slit portion of the first slit and the second slit, so that the contact table is more in comparison with a cup-shaped contact that generates the same magnetic flux density. The mechanical strength is improved, and it is possible to prevent the interruption performance and the withstand voltage performance from being lowered due to the deformation of the contact.
[Brief description of the drawings]
FIG. 1 is a side view of a contact of a vacuum interrupter according to an embodiment of the present invention.
FIG. 2 is a plan view of a contact of the vacuum interrupter shown in FIG.
FIG. 3 is an explanatory diagram of the azimuth angle of the contact of the vacuum interrupter shown in FIG.
4 is a side view showing a partial cross-section in a state where the contacts of the vacuum interrupter shown in FIG. 1 are opposed to each other.
5 is a perspective view of the state shown in FIG. 4. FIG.
6 is a schematic view of a vacuum interrupter using the contact of the vacuum interrupter shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Contact stand 2 Contact plate 3 Contact end plate 4 Reinforcement body 5 1st slit 5a Circumferential slit part 5b Inclined slit part 6 2nd slit 7a, 7b, 7c Coil part 8 Slit 10 Vacuum interrupter 11 Contact (fixing) electrode)
12 Contact (movable electrode)

Claims (5)

While providing a contact plate on the end surface of the contact table, a coil portion is formed by forming a slit in the peripheral surface of the contact table, and a vertical magnetic field along the axial direction of the contact table is formed by a current flowing through the coil portion. In the contact of the vacuum interrupter
A first slit comprising a circumferential slit portion formed on the surface of the end surface of the contact table and an inclined slit portion formed by connecting the slit to the axis of the contact table; From the middle of the contact table in the axial direction, it is composed of a second slit formed to be inclined with respect to the axis of the contact table,
The first slit and the second slit overlap a predetermined range in the contact base axis direction,
A contact of a vacuum interrupter, wherein a linear slit is formed on the contact plate .   2. The contact of a vacuum interrupter according to claim 1, wherein the second slit is formed to open at the other end surface of the contact base. In the contact of the vacuum interrupter according to claim 1 or 2,
The outer diameter D of the contact table is
60mm ≦ D ≦ 200mm
When
For the outer diameter D of the contact table, the length L of the contact table and the number S of the slits are:
0.2D ≦ L ≦ D
0.1D / mm ≦ S ≦ 0.2D / mm
And
An inclination angle α with respect to the axis of the contact base of the inclined slit portion and the second slit of the first slit is,
60 ° ≦ α ≦ 80 °
And
The azimuth angle β of the inclined slit portion and the second slit in the first slit is:
(540 / S) ° ≦ β ≦ (600 / S) °
And
An azimuth angle γ between the inclined slit portion of the first slit and the second slit is:
(120 / S) ° ≦ γ ≦ (600 / S) °
And
The azimuth angle δ of the circumferential slit portion of the first slit is:
(120 / S) ° ≦ δ ≦ (600 / S) °
A vacuum interrupter contact characterized by the above. The contact of the vacuum interrupter according to claim 3,
The thickness W of the contact table is
6mm ≦ W ≦ 12mm
A vacuum interrupter contact characterized by the above. The contacts of the vacuum interrupter according to any one of claims 1 to 4 are arranged on the same axis so that a distance G between the facing contacts is
15mm ≦ G ≦ 100mm
A vacuum interrupter characterized by

Images