JP2010225474A - Vacuum valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vacuum valve having a magnetic field control electrode with improved mechanical strength and breaking characteristics. <P>SOLUTION: The vacuum valve has a pair of contactable/detachable contact points 5, wherein each of the contact points 5 includes: an arm portion 11a extending radially from a center which is fixed to the end of a conducting axis 4; an arc-shaped coil portion 11b connected to the end of the arm portion 11a; a tip portion 11c connected to the end of the coil portion 11b; a contact 12 fixed to the tip portion 11c; a first reinforcing member 20 in which a circular cylinder portion 20b is fixed to the arm portion 11a via a bonding layer 14, and a flange portion 20a is connected to the circular cylinder portion 20b and is provided with an oxide layer 22 to come into contact with the contact 12; and a second reinforcing material 21, in which an inner peripheral portion 21a passes through the circular cylinder portion 20b and an outer peripheral portion 21b is engaged with the coil portion 11b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vacuum valve having a magnetic field control electrode capable of improving mechanical strength and interruption characteristics.

  2. Description of the Related Art Conventionally, vacuum valves having a pair of contact points that can be separated from each other have been known to generate a magnetic field parallel to the axial direction with respect to an arc at the time of current interruption, thereby improving the interruption characteristics (for example, Patent Documents). 1).

  A vacuum valve of this type is shown in FIG. 5, and a fixed-side sealing fitting 2 and a movable-side sealing fitting 3 are sealed at both ends of a cylindrical vacuum insulating container 1 made of ceramics. A fixed-side energizing shaft 4 is fixed through the fixed-side sealing fitting 2, and a fixed-side contact 5 is fixed to the end of the fixed-side energizing shaft 4 in the vacuum insulating container 1.

  A movable side contact 6 that can be moved toward and away from the fixed side contact 5 is opposed to the fixed side contact 5 and is fixed to the end of the movable side energizing shaft 7 that movably penetrates the movable side sealing fitting 3. One end of a telescopic bellows 8 is sealed at an intermediate portion of the movable side energizing shaft 7, and the other end is sealed at an opening of the movable side sealing fitting 3. Thereby, the movable contact 6 can be moved in the axial direction while maintaining the vacuum in the vacuum insulating container 1. An arc shield 9 that surrounds the contacts 5 and 6 is fixed to the intermediate metal fitting 10 to capture metal vapor.

  Next, the contacts 5 and (6) for generating a magnetic field parallel to the axial direction will be described using the fixed side. As shown in FIG. 6, the bottom portion of the bottomed cylindrical coil electrode 11 is fixed to the end of the fixed side energizing shaft 4. The coil electrode 11 includes four arm portions 11a extending radially from the center of the bottom, four arc-shaped coil portions 11b connected to the ends of the arm portions 11a, and connected to the ends of the coil portions 11b so as to protrude in the axial direction. The four tip portions 11c. A disc-shaped contact 12 made of a copper alloy is fixed to each tip 11c.

  A columnar reinforcing member 13 made of a non-magnetic material such as stainless steel is provided in the space between the central portion of the arm portion 11a of the coil electrode 11 and the contact 12 to reinforce mechanical strength. The one end of the reinforcing member 13 and the contact 12, and the other end of the reinforcing member 13 and the central portion of the arm portion 11 a are each provided with a bonding layer 14 by brazing and are firmly bonded.

Japanese Patent No. 3243805 (pages 3 to 4, FIG. 2)

  The above-described conventional vacuum valve has the following problems. Although a force in the compression direction and a tension direction is applied to the contact 12 at the time of opening and closing, mechanical strength is reinforced by the reinforcing member 13. On the other hand, the current flowing from the fixed side energizing shaft 4 flows along with the coil electrode 10 to the reinforcing member 13 via the bonding layer 14. For this reason, the current flowing through the coil electrode 10 that performs magnetic field control is reduced by the ratio of the shunting to the reinforcing member 13, the generated magnetic field is weakened, and as a result, the interruption characteristic is deteriorated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vacuum valve having a magnetic field control electrode capable of improving the interruption characteristics while maintaining mechanical strength.

  In order to achieve the above object, a vacuum valve according to the present invention is a vacuum valve having a pair of contactable and separable contacts, and the contacts are arms extending radially from a central portion fixed to a current-carrying shaft end. An arc-shaped coil part connected to the end of the arm part, a tip part connected to the end of the coil part, a contact fixed to the tip part, and a cylindrical part via a bonding layer to the arm part Is fixed, and the first reinforcing member provided with an oxide film on the collar portion connected to the cylindrical portion and brought into contact with the contactor, the inner peripheral portion penetrates the cylindrical portion, and the outer peripheral portion is And a second reinforcing member locked to the coil portion.

  According to the present invention, the first reinforcing member is disposed between the contact portion and the arm portion of the coil electrode, the second reinforcing member is disposed in the coil portion of the coil electrode, and the first reinforcing member and the second reinforcing member are disposed. Since the member is engaged with the oxide film through the oxide film, most of the energized current flows to the coil electrode to generate a predetermined magnetic field, and the mechanical strength and the cutoff characteristic can be improved.

Sectional drawing which shows the structure of the contact used for the vacuum valve which concerns on Example 1 of this invention. The top view which shows the structure of the contact used for the vacuum valve which concerns on Example 1 of this invention. Sectional drawing which shows the structure of the contact used for the vacuum valve which concerns on Example 2 of this invention. The top view which shows the structure of the contact used for the vacuum valve which concerns on Example 2 of this invention. Sectional drawing which shows the structure of a vacuum valve. Sectional drawing which shows the structure of the contact used for the conventional vacuum valve.

  Hereinafter, a vacuum valve according to the present invention will be described with reference to the drawings.

  First, a vacuum valve according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 is a cross-sectional view showing a contact used in a vacuum valve according to Embodiment 1 of the present invention, and FIG. 2 is a top view showing a contact used in the vacuum valve according to Embodiment 1 of the present invention. In addition, in each figure, the same code | symbol was attached | subjected about the component similar to the past. Since the vacuum valve is the same as the conventional one, its description is omitted. The contact point is the same on the fixed side and the movable side, and will be described using the fixed side. 1 is a cross-sectional view taken along the line AA in FIG.

  As shown in FIGS. 1 and 2, the bottom portion of the bottomed cylindrical coil electrode 11 is fixed to the end of the fixed side energizing shaft 4. The coil electrode 11 includes four arm portions 11a extending radially from the center of the bottom, four arc-shaped coil portions 11b connected to the ends of the arm portions 11a, and connected to the ends of the coil portions 11b so as to protrude in the axial direction. The four tip portions 11c. A disc-shaped contact 12 made of a copper alloy is fixed to each tip 11c. Here, on the inner peripheral surface of the coil portion 11b, a step portion 11b1 is provided on the surface facing the contact 12, and the inner diameter is increased.

  In the space between the central portion of the arm portion 11a of the coil electrode 11 and the contact 12, a first reinforcing member 20 composed of a flange portion 20a made of a nonmagnetic material such as stainless steel and a cylindrical portion 20b is provided. . The flange portion 20a is disposed on the contact 12 side, and the axial surface of the cylindrical portion 20b is brazed to the center portion of the arm portion 11a and is fixed by the bonding layer 14.

  A disc-shaped second reinforcing member 21 having an opening hole in the center passes through the outer periphery of the cylindrical portion 20b, and the inner peripheral portion 21a is sandwiched between the flange portion 20a and the central portion of the arm portion 11a. . The outer diameter of the second reinforcing member 21 is slightly smaller than the inner diameter of the step portion 11b1, and the surface on the arm portion 11a side of the outer peripheral portion 21b is disposed in the step portion 11b1.

  Here, an oxide film 22 is formed on the flange portion 20a of the first reinforcing member 20 and the vicinity of the flange portion 20a of the cylindrical portion 20b and on the entire surface of the second reinforcing member 21. That is, the flange portion 20a of the first reinforcing member 20 is in contact with the contact 12 through a film thickness of several μm. The second reinforcing member 21 is also in contact with the stepped portion 11b1, the flange portion 20a, and the like through a film thickness of several μm. The oxide film 22 can be provided at a predetermined portion by heating the reinforcing members 20 and 21 to several hundred degrees Celsius, but may be formed during an assembly process in a normal atmosphere.

  Next, the movement of each part when the contact 5 is opened and closed will be described.

  First, when the circuit is closed, a force that presses the contact 12 toward the arm portion 11a, that is, a force in a so-called compression direction is applied. However, the contact 12 is in contact with the flange portion 20a of the first reinforcing member 20 via the oxide film 22, and the columnar portion 20b is fixed to the arm portion 11a with the bonding layer 14, so that it deforms. It can be suppressed.

  Next, when the circuit is opened, the contact 12 may be welded and a force in the pulling direction may be applied. However, the outer peripheral part of the contact 12 is fixed to the coil part 11b via the tip part 11c, and a force in the pulling direction is applied to the coil part 11b. In the coil part 11b, the outer peripheral part 21b of the second reinforcing member 21 is in contact with the step part 11b1, and the inner peripheral part 21a is sandwiched between the flange part 20a and the arm part 11a.

  For this reason, the force in the pulling direction applied to the coil portion 11 b is propagated to the first reinforcing member 20 via the second reinforcing member 21. Since the cylindrical portion 20b of the first reinforcing member 20 is firmly fixed to the arm portion 11a, the coil portion 11b is not deformed. As a result, the contact 12 is also not deformed and can be satisfactorily opened even if there is welding.

  Here, when a force in the pulling direction is applied, the outer peripheral portion 21b of the second reinforcing member 21 acts to suppress the stepped portion 11b1 from moving toward the contact 12 side. It is defined that the coil portion 11b is locked to the outer peripheral portion 21b of the reinforcing member 21.

  The current at the time of interruption is because the contact 12 and the shaft surface of the flange 20a are in contact with each other through the oxide film 22, and the flange 20b and the second reinforcing member 21 are also in contact with each other through the oxide film 22. The current diverted between the first reinforcing member 20 and the second reinforcing member 21 is extremely small. Most of the current flows through the coil portion 11b and can generate a predetermined magnetic field. In addition, the oxide film 22 provided on the shaft surface of the flange portion 20a is highly effective in preventing the diversion.

  If the first reinforcing member 20 and the second reinforcing member 21 have a resistivity of 40 times or more with respect to the current-carrying part such as the coil electrode 11, the shunt current can be further suppressed and a predetermined magnetic field can be generated. Can do.

  According to the vacuum valve of the first embodiment, the flange portion 20a of the first reinforcing member 20 is disposed on the contact 12 side, the columnar portion 20b is fixed to the arm portion 11a of the coil electrode 11, and the coil portion 20b is Since the two reinforcing members 21 are arranged and the first reinforcing member 20 and the second reinforcing member 21 are provided with the oxide film 22 to be engaged, the force in the compression direction and the pulling direction at the time of opening and closing is Mechanical reinforcement can be performed, and most of the energized current can be passed through the coil electrode 11 to generate a predetermined magnetic field.

  In the first embodiment, the first reinforcing member 20 and the second reinforcing member 21 have been described using a non-magnetic material. However, a magnetic material such as a neodymium magnet may be used and is generated by the coil electrode 11. The magnetic field can be strengthened.

  Further, although the magnetic field control type electrode has been described as the coil electrode 11, the first reinforcing member is also used in an electrode in which a plurality of slits that obliquely cross the axial direction are provided on the outer peripheral portion of the bottomed cylindrical electrode. By using 20 and the second reinforcing member 21, it is possible to improve the blocking characteristic while maintaining the mechanical strength.

  Next, a vacuum valve according to Embodiment 2 of the present invention will be described with reference to FIGS. 3 is a cross-sectional view showing a contact used in a vacuum valve according to Embodiment 2 of the present invention, and FIG. 4 is a top view showing a contact used in a vacuum valve according to Embodiment 2 of the present invention. The difference between the second embodiment and the first embodiment is the shape of the reinforcing member. 3 and 4, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIGS. 3 and 4, the third reinforcing member 23 penetrating the cylindrical portion 20 b of the first reinforcing member 20 has a bowl shape having an opening hole at the center. The hook-shaped outer peripheral portion 23b is disposed so as to be sandwiched between the contact 12 and the coil portion 11b, and the inner peripheral portion 23a is sandwiched between the arm portion 11a and the flange portion 20a. In addition, a U-shaped groove 23c is provided in the vicinity of the tip 11c of the coil electrode 11 so as not to contact. In addition, the coil part 11b does not provide the level | step-difference part 11b1 like Example 1. FIG.

  When the circuit is closed, the deformation of the contact 12 can be suppressed by the first reinforcing member 20 as in the first embodiment. Further, when the circuit is opened, the outer peripheral portion 23b of the third reinforcing member 23 is in contact with the coil portion 11b, so that the coil portion 11b is not deformed.

  Here, when a force in the pulling direction is applied, the outer peripheral portion 23b of the third reinforcing member 23 acts to suppress the coil portion 11b from moving toward the contact 12 side. It is defined that the coil portion 11b is locked to the outer peripheral portion 23b of the reinforcing member 23.

  According to the vacuum valve of the second embodiment, in addition to the effects of the first embodiment, the cross-sectional area of the coil portion 11b can be increased, so that the energization characteristics can be improved.

DESCRIPTION OF SYMBOLS 1 Vacuum insulating container 2 Fixed side sealing metal fitting 3 Movable side sealing metal fitting 4 Fixed side energizing shaft 5 Fixed side contact 6 Movable side contact 7 Movable side energizing shaft 8 Bellows 9 Arc shield 10 Intermediate metal fitting 11 Coil electrode 11a Arm part 11b Coil Part 11c Tip part 12 Contactor 13 Reinforcing member 14 Joining layer 20 First reinforcing member 20a Gutter part 20b Cylindrical part 21 Second reinforcing member 21a, 23a Inner peripheral part 21b, 23b Outer peripheral part 22 Oxide film 23 Third reinforcing Member 23c Groove

Claims (5)

A vacuum valve having a pair of contactable and separable contacts,
The contact point is an arm portion extending radially from a central portion fixed to the end of the energizing shaft;
An arc-shaped coil part connected to the end of the arm part;
A tip connected to the end of the coil part;
A contact fixed to the tip,
A first reinforcing member in which a cylindrical portion is fixed to the arm portion via a bonding layer, an oxide film is provided on a collar portion connected to the cylindrical portion, and is brought into contact with the contact;
A vacuum valve comprising: a second reinforcing member having an inner peripheral portion penetrating the cylindrical portion and an outer peripheral portion locked to the coil portion. The second reinforcing member is disc-shaped,
The inner periphery is sandwiched between the arm and the buttocks,
The vacuum valve according to claim 1, wherein an outer peripheral portion is disposed in a step portion provided in the coil portion. The second reinforcing member has a bowl shape,
The inner periphery is sandwiched between the arm and the buttocks,
The vacuum valve according to claim 1, wherein an outer peripheral portion is disposed between the coil portion and the contact.   4. The vacuum valve according to claim 1, wherein the first reinforcing member and the second reinforcing member are heated and the oxide film is provided on a predetermined portion. 5.   The vacuum valve according to any one of claims 1 to 4, wherein the first reinforcing member and the second reinforcing member are formed of a magnetic material.

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