JP2011096474A - Vacuum valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress temperature rise of a magnetic body installed in an electrode to generate a magnetic field. <P>SOLUTION: A vacuum valve is equipped with a pair of attachable/detachable contacts 5 having a magnetic field generating electrode 5a such as a contrate electrode and a longitudinal magnetic field electrode to generate a magnetic field in order to move an arc, an annular magnetic body 5b installed in the magnetic field generating electrode 5a, and an attachable/detachable contactor 5c connected to the magnetic field generating electrode 5a. An open groove 5b1 to open a circumferential direction is installed at the magnetic body 5b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vacuum valve having a pair of contact points that can be contacted and separated, and more particularly, to a vacuum valve that can improve magnetic field strength with a magnetic material.

  Conventionally, an electrode that generates a magnetic field orthogonal to an arc and improves the magnetic field strength by using an electrode that generates a magnetic field orthogonal to the arc is known (see, for example, Patent Document 1). .)

  In this type of vacuum valve, as shown in FIG. 4, a fixed-side sealing fitting 2 and a movable-side sealing fitting 3 are sealed at both end openings of a cylindrical vacuum insulating container 1. 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 vacuum insulating container 1. The fixed contact 5 includes an electrode 5a having a cup-shaped bottom fixed to the end of the fixed energizing shaft 4, an annular magnetic body 5b provided in the electrode 5a, and a disk fixed to the opening of the electrode 5a. It is comprised with the contact 5c of a shape. On the outer periphery of the electrode 5a, there are provided a plurality of slits 5d that obliquely cross the axial direction.

  A movable contact 6 that can be moved toward and away from the fixed contact 5 is fixed to the end of the movable energizing shaft 7 that movably penetrates the movable seal 3. The configuration of the movable contact 6 is the same as that of the fixed contact 5. One end of a telescopic bellows 8 is sealed to the middle portion of the movable side energizing shaft 7 and the other end is sealed to the movable side sealing fitting 3. A cylindrical arc shield 9 is provided around both the contacts 5 and 6.

  The contacts 5 and 6 having such an electrode 5a are generally called control electrodes and generate a magnetic field extending radially from the axis of the electrode 5a. Further, the magnetic body 5b can increase the magnetic field strength and improve the cutoff characteristic.

  On the other hand, as another electrode that generates a magnetic field, it has an arm part extending radially from the axis of the electrode and an arc-shaped coil part connected to the tip of the arm part to generate a magnetic field parallel to the axial direction. There is a so-called longitudinal magnetic field electrode that diffuses the arc. Also in such a longitudinal magnetic field electrode, a plurality of L-shaped magnetic bodies are provided on the inner peripheral side surface of the coil portion and the end portion of the coil portion to improve the magnetic field strength (see, for example, Patent Document 2). .)

JP 2008-262772 A (third page, FIG. 1) JP 2000-76964 A (page 4, FIG. 1)

  The above-described conventional vacuum valve has the following problems. In the case where the annular magnetic body 5b is used in the control electrode, an eddy current is generated during energization, leading to an increase in temperature. When the temperature rises, the magnetic field strength decreases. Further, in the case of using a plurality of magnetic bodies in the longitudinal magnetic field electrode, although the magnetic bodies are arranged at a predetermined interval in the circumferential direction of the electrode, the continuity of the magnetic field in the circumferential direction is lost and the magnetic field strength is reduced. It will be. Furthermore, the number of parts is large and the structure is complicated.

  The present invention has been made to solve the above problem, and provides a vacuum valve capable of improving the magnetic field strength by providing a magnetic body having a simple structure in an electrode for generating a magnetic field for moving an arc. With the goal.

  In order to achieve the above object, a vacuum valve according to the present invention includes a magnetic field generating electrode for generating a magnetic field for moving an arc, an annular magnetic body provided in the magnetic field generating electrode, and a magnetic field generating electrode. A vacuum valve provided with a pair of contactable contacts having a connected contact, wherein the magnetic body is provided with an open groove that opens in a circumferential direction.

  According to the present invention, the annular magnetic body housed in the electrode is provided with an open groove that opens in the circumferential direction and a plurality of cut grooves that are cut in a part of the circumferential direction. Eddy currents and induced currents flowing through the body can be suppressed, and the magnetic field strength in the circumferential direction can be made uniform and improved.

Sectional drawing which shows the structure of the contact used for the vacuum valve which concerns on Example 1 of this invention. The perspective view which shows the electrode and magnetic body which comprise the contact used for the vacuum valve which concerns on Example 1 of this invention. The perspective view which shows the electrode and magnetic body which comprise the contact used for the vacuum valve which concerns on Example 2 of this invention. Sectional drawing which shows the structure of the conventional vacuum valve.

  An annular magnetic body provided with an open groove that opens in the circumferential direction and a plurality of cut grooves that are cut in a part of the circumferential direction is housed in an electrode that generates a magnetic field for moving the arc. To do. Embodiments of the present invention will be described below 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 configuration of a contact used in a vacuum valve according to Embodiment 1 of the present invention, and FIG. 2 shows an electrode and a magnetic body constituting the contact used in the vacuum valve according to Embodiment 1 of the present invention. It is a perspective view shown. In FIG. 1 and FIG. 2, the same components as those in the prior art are denoted by the same reference numerals. Moreover, since the structure of a vacuum valve is the same as the past, the description is abbreviate | omitted. Since the contact point is the same on the fixed side and the movable side, description will be made using the fixed side.

  As shown in FIG. 1 and FIG. 2, the fixed contact 5 has an annular shape made of a cup-shaped electrode 5a and an iron alloy having an outer diameter smaller than the inner diameter of the electrode 5a and housed in the space of the electrode 5a. The magnetic body 5b and a disk-shaped contact 5c fixed to the opening of the electrode 5a. On the outer periphery of the electrode 5a, there are provided a plurality of slits 5d that obliquely cross the axial direction. The magnetic body 5b is fixed to the bottom of the electrode 5a with an adhesive as necessary.

  Here, the magnetic body 5b is provided with an open groove 5b1 having a predetermined width of, for example, 1 mm, which is partially opened in the circumferential direction. In addition, a plurality of cut grooves 5b2 that are cut at equal intervals in a part in the circumferential direction are provided by machining. The cut grooves 5b2 are alternately arranged with cuts from the contact 5c side and cuts from the bottom of the electrode 5a, and has a predetermined width of 1 mm, for example.

  Thereby, in the magnetic body 5b, the circulating induced current can be interrupted by the open groove 5b1. Moreover, since the plurality of cut grooves 5b2 are provided, the current flowing in the circumferential direction is divided at a plurality of locations, eddy currents can be suppressed, and temperature rise can be suppressed. Furthermore, although the magnetic body 5b has an open groove 5b1, it is configured in an annular shape, so that the magnetic field strength generated in the circumferential direction is made uniform. This magnetic field is superimposed on the magnetic field generated by the electrode 5a itself, so that the magnetic field distribution between the contacts can be made appropriate and the interruption characteristics can be improved.

  Moreover, the magnetic body 5b is a single body, has a small number of parts, and can have a simple structure. In addition, when an oxide film such as iron oxide is provided on the magnetic body 5b, a current diverted to the magnetic body 5b can be suppressed.

  Here, in the so-called control electrode in which the slit 5d is provided on the outer periphery of the electrode 5a, a magnetic field orthogonal to the arc is generated and the arc is rotationally driven in the circumferential direction. An electrode that generates a magnetic field for moving an arc in this way is defined as a magnetic field generating electrode.

  According to the vacuum valve of the first embodiment, the annular magnetic body 5b provided in the electrode 5a is provided with the open groove 5b1 that opens in the circumferential direction and the plurality of cut grooves 5b2 that divide the current in the circumferential direction. Since it is provided, eddy currents and induced currents can be suppressed, and the magnetic field strength in the circumferential direction can be made uniform.

  In the first embodiment, the magnetic body 5b is provided with the open groove 5b1 and the cut groove 5b2. However, even if only the open groove 5b1 is provided, the induced current circulating around the magnetic body 5b can be cut off. Temperature rise can be suppressed.

  Next, a vacuum valve according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 3 is a perspective view showing an electrode and a magnetic body constituting a contact used in the vacuum valve according to the second embodiment of the present invention. The difference between the second embodiment and the first embodiment is the electrode structure. In FIG. 3, 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 FIG. 3, the electrode 10 is connected to the arm portion 10a extending radially from the end of the fixed-side energizing shaft 4, the arc-shaped coil portion 10b connected to the tip of the arm portion 10a, and the tip of the coil portion 10b. And the connected portion 10c. A contact (not shown) is connected to the connection portion 10c. In the figure, the electrode 10 is divided into four parts, but the strength of the magnetic field can be controlled by changing the number of divisions.

  The electrode 10 is provided with an annular magnetic body 11 made of an iron alloy having an outer diameter smaller than the inner diameter of the coil portion 10b on the inner peripheral side surface of the coil portion 10b. The magnetic body 11 is provided with an open groove 11a that is partially opened in the circumferential direction by machining. Moreover, the 1st cut groove 11b cut into the width | variety slightly larger than the width | variety of the arm part 10a is provided, and it fits in the arm part 10a. A plurality of second cut grooves 11c are provided between the first cut grooves 11b.

  Thereby, the induced current that circulates around the magnetic body 11 can be blocked by the open groove 11. Further, the plurality of first cut grooves 11b and second cut grooves 11c can divide the current flowing in the circumferential direction, thereby suppressing eddy currents and suppressing temperature rise. Furthermore, although the magnetic body 11 has an open groove 11a, it is configured in an annular shape, so that the magnetic field strength in the circumferential direction can be made uniform.

  Here, a so-called longitudinal magnetic field electrode having the arm portion 10a and the coil portion 10b generates a magnetic field parallel to the arc and diffuses the arc in the radial direction. An electrode that generates a magnetic field for moving an arc in this way is defined as a magnetic field generating electrode.

  According to the vacuum valve of Example 2, the eddy current flowing in the magnetic body 11 can be suppressed even in the longitudinal magnetic field electrode, and the same effect as in Example 1 can be obtained.

DESCRIPTION OF SYMBOLS 1 Vacuum insulation container 2 Fixed side sealing metal fitting 3 Movable side sealing metal fitting 4 Fixed side electricity supply axis | shaft 5 Fixed side contact 5a, 10 Electrode 5b, 11 Magnetic body 5b1, 11a Opening groove | channel 5b2, 11b, 11c Cutting groove 5c Contactor 5d Slit 6 Movable side contact 7 Movable side energizing shaft 8 Bellows 9 Arc shield 10a Arm part 10b Coil part 10c Connection part

Claims (5)

A magnetic field generating electrode for generating a magnetic field for moving the arc;
An annular magnetic body provided in the magnetic field generating electrode;
A vacuum valve having a pair of contactable contacts having a contact connected to the magnetic field generating electrode;
The said magnetic body is provided with the open groove | channel which opens the circumferential direction, The vacuum valve characterized by the above-mentioned.   The vacuum valve according to claim 1, wherein a plurality of cut grooves are provided in a circumferential direction of the magnetic body.   3. The vacuum valve according to claim 1, wherein the magnetic field generating electrode is a control electrode provided with a slit on an outer periphery of a cup-shaped electrode.   3. The vacuum valve according to claim 1, wherein the magnetic field generating electrode is a longitudinal magnetic field electrode having a radially extending arm portion and a coil portion connected to the arm portion.   The vacuum valve according to any one of claims 1 to 4, wherein an oxide film is provided on the magnetic body.

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