Opening / closing device

Abstract

An opening / closing device (100) comprises: a sealed container (1) in which an insulation gas is sealed; a fixed electrode (5) which is provided inside the sealed container (1); a movable electrode (3) which is provided in a movable manner inside the sealed container (1) and has a cylindrical cylinder (32), a piston (33) that is provided inside the cylinder (32), and a movable-side contact (31) that is smaller in diameter than the cylinder (32) and is fixed to the piston (33), the movable-side contact (31) having formed therein a ventilation hole (312a) for connecting the space inside the movable-side contact (31) to a buffer chamber (41) that is a space formed between the cylinder (32) and the movable-side contact (31); and a crossflow formation part (42) which causes a gas flow to include a component that is in a direction orthogonal to the central axis of the movable-side contact (31), the gas flow being drawn in by the movable-side contact (31) during an opening operation for transitioning from a closed state in which the movable electrode (3) is in contact with the fixed electrode (5) to an open state in which the movable electrode (3) is separated from the fixed electrode (5).

Description

Switchgear

[0001] The present disclosure relates to a switchgear that interrupts current in a sealed container filled with insulating gas.

[0002] A known device for interrupting high voltage current is a switchgear that interrupts current within a sealed container filled with insulating gas. The switchgear includes a fixed electrode fixed within the sealed container and a movable electrode that is movably installed within the sealed container. In a closed state where the movable electrode and the fixed electrode are in contact, the switchgear passes current, and in an open state where the movable electrode is separated from the fixed electrode, the switchgear interrupts current.

[0003] During the opening operation, which transitions from a closed state to an open state, an arc occurs between the movable electrode and the fixed electrode. If an arc exists between the movable electrode and the fixed electrode, current will flow even if the movable electrode and the fixed electrode are not in contact. For this reason, it is necessary to quickly extinguish the arc that occurs between the movable electrode and the fixed electrode during the opening operation.

[0004] Patent Document 1 discloses a switching device that uses air as an insulating medium, forms a negative pressure chamber with a cylindrical movable contact, a piston linked to the movable contact, and a cylinder, and improves arc extinguishing performance by increasing the air suction flow rate near the surface of the opening at the tip of the movable contact using the pressure in the negative pressure chamber during the opening operation.

[0005] Japanese Patent Application Publication No. 5-250966

[0006] In the switchgear disclosed in Patent Document 1, the opening at the tip of the movable contactor is open in the same direction as the axial direction of the opening and closing motion of the movable contactor. In this case, the gas sucked into the opening also flows in the axial direction of the device. The arc generated between the opposing ends of the fixed contactor and the movable contactor when current is interrupted also flows in the same direction as the axial direction of the opening and closing motion of the movable contactor. This causes a problem in that only a portion of the gas flow generated near the surface of the opening that flows near the arc contributes to cooling the arc, while the majority does not contribute to cooling the arc.

[0007] The present disclosure has been made in view of the above, and has an object to provide a switching device with improved arc cooling performance.

[0008] In order to solve the above-mentioned problems and achieve the object, a switchgear according to the present disclosure includes a sealed container filled with insulating gas, a fixed electrode installed inside the sealed container, a cylindrical cylinder, a piston installed in the cylinder, and a movable contactor having a smaller diameter than the cylinder and fixed to the piston, the movable contactor being movably installed inside the sealed container, the movable contactor having a vent hole formed in it that connects a puffer chamber, which is a space formed between the cylinder and the movable contactor, to a space inside the movable contactor. The switchgear also includes a cross-flow forming unit that adds a component in a direction perpendicular to the central axis of the movable contactor to a gas flow that is drawn into the movable contactor during an opening operation in which the movable electrode transitions from a closed state in which it contacts the fixed electrode to an open state in which it is separated from the fixed electrode.

[0009] According to the present disclosure, an effect is achieved in that a switching device with improved arc cooling performance can be obtained.

[0010] 3 is a cross-sectional view of a switchgear according to embodiment 1; sectional view of a switchgear according to embodiment 1; enlarged view of a movable part of a movable electrode of a switchgear according to embodiment 1; oblique view of a support base of a switchgear according to embodiment 1; diagram showing arc-extinguishing operation during contact opening operation of a switchgear according to embodiment 1; enlarged view of a movable part of a movable electrode of a switchgear according to embodiment 2; schematic view of gas flow generated in the movable electrode of a switchgear according to embodiment 2; oblique view of a cross-flow forming part of a switchgear according to embodiment 3; side view of a cross-flow forming part of a switchgear according to embodiment 3; diagram showing a schematic gas flow of a switchgear according to embodiment 3; enlarged view of a movable part of a movable electrode of a switchgear according to embodiment 4; sectional view of a switchgear according to embodiment 5; enlarged view of a movable part of a movable electrode of a switchgear according to embodiment 5; enlarged view of a movable part of a movable electrode of a switchgear according to embodiment 6; diagram showing magnetic field lines generated by a permanent magnet of the movable electrode of a switchgear according to embodiment 6; diagram showing contact opening operation of a switchgear according to embodiment 6

[0011] An opening / closing device according to an embodiment will be described in detail below with reference to the drawings, but the present invention is not limited to the embodiment.

[0012] 1 and 2 are cross-sectional views of a switchgear according to embodiment 1. The switchgear 100 includes a sealed container 1 filled with insulating gas, a fixed electrode 5 installed inside the sealed container 1, and a movable electrode 3 installed movably inside the sealed container 1. Note that Fig. 1 shows a closed state in which the movable electrode 3 and the fixed electrode 5, which will be described later, are in contact, and Fig. 2 shows an open state in which the movable electrode 3 and the fixed electrode 5 are separated.

[0013] The fixed electrode 5 includes a cylindrical fixed contactor 51, and the movable electrode 3 includes a cylindrical movable contactor 31 that is thinner than the fixed contactor 51. The outer diameter of the movable contactor 31 is slightly larger than the inner diameter of the fixed contactor 51, and in a closed state, the movable contactor 31 and the fixed contactor 51 are closely attached to each other due to the elastic forces of the movable contactor 31 and the fixed contactor 51. Here, a configuration in which the fixed contactor 51 is cylindrical and has a larger diameter than the movable contactor 31 is taken as an example, but the fixed contactor 51 may also be tulip-shaped. The state in which the movable contactor 31 and the fixed contactor 51 are in contact is referred to as a "closed state," and the state in which the movable contactor 31 is separated from the fixed contactor 51 is referred to as an "open state."

[0014] The switching device 100 is closed when the movable electrode 3 comes into contact with the fixed electrode 5, and is opened when the movable electrode 3 moves away from the fixed electrode 5.

[0015] The movable electrode 3 includes, in addition to the movable contactor 31, a cylindrical cylinder 32 having a larger diameter than the movable contactor 31, a piston 33 installed inside the cylinder 32, and a rod 34 to which the piston 33 is fixed. The rod 34 is connected to an operating rod of an operating device (not shown), and moves the piston 33 by a driving force transmitted from the operating device (not shown). As the piston 33 moves, the movable contactor 31 moves inside the cylinder 32.

[0016] 3 is an enlarged view of the movable portion of the movable electrode of the switchgear according to embodiment 1. The movable contactor 31 includes a first portion 311 that contacts and separates from the fixed contactor 51, and a second portion 312 that supports the first portion 311. As shown in FIGS. 1 and 2, the second portion 312 is fixed to the piston 33. A support base 35, a first cylinder 371, and a second cylinder 372 are installed within the movable contactor 31. The support base 35 is made of a non-magnetic material such as a non-magnetic metal or an insulator. The first cylinder 371 is made of a magnetic material, and the second cylinder 372 is made of a non-magnetic material.

[0017] 4 is a perspective view of the support base of the opening and closing device according to Embodiment 1. The support base 35 includes a cylindrical holding portion 351 into which the rod-shaped member 39 is fitted, and support legs 352 extending radially outward from an outer circumferential surface 351 a of the holding portion 351.

[0018] 3, the support base 35 is fixed inside the movable contactor 31 by sandwiching the support leg 352 between a first cylinder 371 and a second cylinder 372. By forming slits in the first cylinder 371 and the second cylinder 372 and fitting the support leg 352 into the slits, it is possible to prevent the support base 35 from rotating around the axis of the movable contactor 31.

[0019] The rod-shaped member 39 is made of a non-magnetic material. An insulating layer 40 is provided on the surface of the rod-shaped member 39. The insulating layer 40 is formed by wrapping insulating tape around a non-magnetic core material or by molding an insulating material. A cross-flow forming portion 42 is formed on the fixed-side end of the rod-shaped member 39. The cross-flow forming portion 42 is frustum-shaped, with its diameter uniformly increasing as it approaches the fixed-side contactor 51 along the axial direction of the movable-side contactor 31. That is, the outer peripheral surface 421 of the cross-flow forming portion 42 is a linearly tapered surface whose distance from the central axis of the movable-side contactor 31 uniformly increases toward the end 422 facing the fixed-side contactor 51, and is a surface inclined with respect to the central axis of the movable-side contactor 31.

[0020] The gap between the rod-shaped member 39 and the movable contact 31 serves as a nozzle portion 60 through which insulating gas passes. The rod-shaped member 39 is installed so that the cross-flow forming portion 42 protrudes further toward the fixed contact 51 than the fixed end of the movable contact 31, or so that the fixed end of the movable contact 31 and the cross-flow forming portion 42 are flush with each other.

[0021] A vent hole 312a is formed in the second portion 312 of the movable contact 31 so as to penetrate radially. A puffer chamber 41 is formed between the cylinder 32 and the movable contact 31. The volume of the puffer chamber 41 changes with the movement of the piston 33. In a closing operation in which the open contact state is changed to a closed contact state, the volume of the puffer chamber 41 decreases, and in an opening operation in which the closed contact state is changed to an open contact state, the volume of the puffer chamber 41 increases.

[0022] When the volume of the puffer chamber 41 increases, gas in the sealed container 1 is sucked in through the opening at the fixed end of the movable contactor 31, and a gas flow is generated in the nozzle portion 60 in the gap between the movable contactor 31 and the rod-shaped member 39.

[0023] FIG. 5 is a diagram illustrating the arc-extinguishing operation during the opening operation of the switchgear according to embodiment 1. FIG. 5 illustrates the arc-extinguishing operation during the opening operation in a cross section of the movable electrode 3. In FIG. 5, the dashed arrow indicates the gas flow generated by the increase in the volume of the puffer chamber 41. When the movable contact 31 moves away from the fixed contact 51 during the opening operation, an arc 70 is generated between the movable contact 31 and the fixed contact 51. In FIG. 5, the arc 70 is generated at position P. The arc 70 generated between the movable contact 31 and the fixed contact 51 is sucked into the movable contact 31 by the gas flow generated in the nozzle portion 60 as the volume of the puffer chamber 41 increases. In FIG. 5, the arc 70 moves from position P to position Q due to the gas flow generated in the nozzle portion 60.

[0024] Since the rod-shaped member 39 on which the cross-flow forming portion 42 is formed is disposed at the opening of the movable contact 31, the insulating gas sucked into the nozzle portion 60 forms a gas flow including a radial component directed toward the central axis of the movable contact 31 outside the cylinder of the movable contact 31, and as the insulating gas enters the interior of the cylinder of the movable contact 31, the radial component perpendicular to the axial direction of the central axis of the movable contact 31 decreases, and the flow changes to a flow parallel to the axial direction. Therefore, outside the cylinder of the movable contact 31, the insulating gas flow intersects with the arc 70. Therefore, outside the cylinder of the moving contact 31, a low-temperature gas flow that is not heated by the arc 70 is blown onto the arc 70, accelerating the cooling of the arc 70 and improving the arc-extinguishing performance.

[0025] Because an insulating layer 40 is formed on the surface of the rod-shaped member 39, when the arc 70 comes into contact with the insulating layer 40 on the surface of the rod-shaped member 39, the insulator forming the insulating layer 40 evaporates due to the heat of the arc 70, generating an insulating gas. The insulating gas generated from the insulating layer 40 on the surface of the rod-shaped member 39 mixes with the arc 70, further cooling the arc 70 and making it easier to extinguish. If the insulating layer 40 is worn away by the arc 70, the rod-shaped member 39 can be removed from the support base 35 and rewrapped with insulating tape or replaced with another rod-shaped member 39, thereby restoring it to its original state.

[0026] The switchgear 100 according to the first embodiment generates a gas flow including a radial component perpendicular to the axial direction of the central axis of the moving contactor 31 at the fixed-side opening of the moving contactor 31, thereby making it possible to cause the gas flow to intersect with the arc 70 and improve the cooling performance of the arc 70. Therefore, the switchgear 100 according to the first embodiment can obtain interrupting performance that satisfies the required switching duty even if dry air is used as the insulating gas sealed in the sealed container 1.

[0027] In the above description, the outer peripheral surface 421 of the cross-flow forming portion 42 is described as a linearly tapered surface, but the outer peripheral surface 421 of the cross-flow forming portion 42 may be a parabolic tapered surface or a logarithmic tapered surface. By forming the outer peripheral surface 421 of the cross-flow forming portion 42 as a parabolic tapered surface or a logarithmic tapered surface, a gas flow having a high proportion of components perpendicular to the axial direction of the moving contact 31 can be generated outside the cylinder of the moving contact 31, thereby further improving the arc-extinguishing performance of the arc 70. Furthermore, by forming the cross-flow forming portion 42 into a T-shape in side view, the proportion of the component perpendicular to the axial direction of the gas flow generated outside the cylinder of the moving contact 31 can be further increased. However, if the gas flow path is bent, flow path resistance increases and the gas flow velocity is likely to decrease. Therefore, from the viewpoint of preventing an increase in flow path resistance, it is preferable that the outer peripheral surface 421 of the cross-flow forming portion 42 be a tapered surface.

[0028] Embodiment 2. Fig. 6 is an enlarged view of the movable portion of the movable electrode of a switching device according to embodiment 2. The switching device 100 according to embodiment 2 differs from the switching device 100 according to embodiment 1 in that the cross-flow forming portion 42 formed on the fixed end of the rod-shaped member 39 has a teardrop shape in side view.

[0029] 7 is a schematic diagram of a gas flow generated at the movable electrode of the switchgear according to embodiment 2. Because the cross-flow forming portion 42 has a teardrop shape in side view, a gas accumulation of insulating gas heated by the arc 70 is not formed in the region 11 adjacent to the fixed side of the cross-flow forming portion 42. Therefore, the switchgear 100 according to embodiment 2 can prevent re-ignition of the arc 70 caused by high-temperature insulating gas remaining near the movable-side contactor 31.

[0030] Embodiment 3. Fig. 8 is a perspective view of a cross-flow forming part of a switchgear according to embodiment 3. Fig. 9 is a side view of the cross-flow forming part of a switchgear according to embodiment 3. The switchgear 100 according to embodiment 3 differs from the switchgear 100 according to embodiment 1 in that the cross-flow forming part 42 is pinwheel-shaped. In the switchgear 100 according to embodiment 3, the cross-flow forming part 42 is formed in a pinwheel shape by forming a spiral groove 423 in a truncated cone. A side surface 424 of the groove 423 is an inclined surface whose position around the axis changes along the axial direction of the central axis of the moving-side contactor 31.

[0031] 10 is a diagram schematically illustrating the gas flow in the switchgear according to embodiment 3. By providing the pinwheel-shaped cross-flow forming portion 42, the gas flow is rectified by the side surface of the groove 423, and a spiral gas flow around the central axis of the moving contact 31 is formed inside the cylinder of the moving contact 31.

[0032] Since the gas flow inside the cylinder of the movable contact 31 is a spiral flow, the arc 70 is blown with a low-temperature gas flow even inside the movable contact 31, improving the arc extinguishing performance.

[0033] 11 is an enlarged view of the movable portion of the movable electrode of a switching device according to embodiment 4. The switching device 100 according to embodiment 4 differs from the switching device 100 according to embodiment 1 in that it does not include a rod-shaped member 39 and the cross-flow forming part 42 is supported by a support base 35.

[0034] The switchgear according to the fourth embodiment, like the switchgear 100 according to the first embodiment, generates a gas flow including a radial component perpendicular to the axial direction of the central axis of the moving contactor 31 at the fixed-side opening of the moving contactor 31, thereby allowing the gas flow to intersect with the arc, thereby improving the cooling performance of the arc 70. Therefore, the switchgear 100 according to the fourth embodiment can obtain interrupting performance that satisfies the required switching duty even if dry air is used as the insulating gas sealed in the sealed container 1.

[0035] Embodiment 5. Fig. 12 is a cross-sectional view of a switching device according to embodiment 5. Fig. 13 is an enlarged view of the movable portion of the movable electrode of the switching device according to embodiment 5. The switching device 100 according to embodiment 5 does not include the support base 35, the first cylinder 371, the second cylinder 372, and the rod-shaped member 39. In addition, the movable contactor 31 is not divided into the first part 311 and the second part 312, but is formed as a single unit. Other than this, it is the same as the switching device 100 according to embodiment 1.

[0036] A cross-flow forming portion 313 is formed at the fixed-side end of the moving-side contactor 31. The cross-flow forming portion 313 has a tapered surface whose distance from the central axis of the moving-side contactor 31 increases uniformly as it approaches the fixed-side contactor 51 along the axial direction of the moving-side contactor 31. In other words, the cross-flow forming portion 313 has a surface that is inclined with respect to the central axis of the moving-side contactor 31.

[0037] The gas flow sucked into the movable contact 31 during the opening operation flows along the tapered surface of the cross flow forming section 313, and as it is sucked into the movable contact 31, the component directed toward the central axis of the movable contact 31 decreases, and the flow changes to one parallel to the axial direction of the movable contact 31.

[0038] The switchgear 100 according to the fifth embodiment, like the switchgear 100 according to the first embodiment, generates a gas flow including a radial component perpendicular to the axial direction of the central axis of the moving contactor 31 at the opening on the fixed side of the moving contactor 31, thereby allowing the gas flow to intersect with the arc, thereby improving the cooling performance of the arc 70. Therefore, the switchgear 100 according to the fifth embodiment can obtain interrupting performance that satisfies the required switching duty even if dry air is used as the insulating gas sealed in the sealed container 1.

[0039] Sixth Embodiment. Figure 14 is an enlarged view of the movable portion of the movable electrode of a switchgear according to the sixth embodiment. In the switchgear 100 according to the sixth embodiment, the rod-shaped member 39 is made of a magnetic material, and a permanent magnet 36 is fitted into the support base 35. The rod-shaped member 39 is installed in close contact with the fixed side of the permanent magnet 36. A cap 43 is installed at the fixed end of the rod-shaped member 39. The cap 43 is frustum-shaped, with a diameter that uniformly increases from the movable contactor 31 toward the fixed contactor 51 along the axial direction of the movable contactor 31. That is, the outer peripheral surface 431 of the cap 43 is a linearly tapered surface whose diameter uniformly increases toward the end 432 facing the fixed contactor 51, and is inclined with respect to the axial direction. In the sixth embodiment, the cross-flow forming section 42 having a surface inclined with respect to the central axis of the movable contactor 31 is constituted by the cap 43.

[0040] In the switching device 100 according to the sixth embodiment, the opening of the holding portion 351 on the fixed contact 51 side in the arrangement direction of the moving contact 31 and the fixed contact 51 is smaller than the permanent magnet 36, and the opening on the moving contact 31 side in the arrangement direction of the moving contact 31 and the fixed contact 51 is larger than the permanent magnet 36, and the permanent magnet 36 is fitted into the opening on the moving contact 31 side in the arrangement direction of the moving contact 31 and the fixed contact 51. The opening of the holding portion 351 on the moving contact 31 side in the arrangement direction of the moving contact 31 and the fixed contact 51 is closed by a cover 38 made of a magnetic material, so that the permanent magnet 36 does not fall out of the holding portion 351. A rod-shaped member 39 is fitted into the opening on the fixed side of the holding portion 351, and the rod-shaped member 39 is in close contact with the permanent magnet 36 as described above.

[0041] 15 is a diagram showing magnetic field lines generated by the permanent magnet of the movable electrode of the switchgear according to embodiment 6. Because the rod-shaped member 39 and the cover 38 are made of a magnetic material, while the support base 35 is made of a non-magnetic material, the magnetic field lines generated by the permanent magnet 36, indicated by arrows in FIG. 15, easily pass through the rod-shaped member 39 and the cover 38 but have difficulty passing through the support leg 352. Furthermore, because the first cylinder 371 is made of a magnetic material, while the second cylinder 372 is made of a non-magnetic material, and the rod-shaped member 39 is longer than the cover 38, the magnetic field generated by the permanent magnet 36 on the side where the fixed contact 51 is installed is stronger than the magnetic field generated by the permanent magnet 36 on the side opposite to the side where the fixed contact 51 is installed. Although magnetic lines of force pass more easily through the rod-shaped member 39 when the rod-shaped member 39 is in close contact with the permanent magnet 36, even if a magnetic gap exists between the rod-shaped member 39 and the permanent magnet 36, the magnetic field generated by the permanent magnet 36 on the side where the fixed contactor 51 is installed can be stronger than the magnetic field generated by the permanent magnet 36 on the side opposite the side where the fixed contactor 51 is installed. Furthermore, the first tube 371 may be made of a non-magnetic material. Even if the first tube 371 is made of a non-magnetic material, because the rod-shaped member 39 is installed adjacent to the fixed side of the permanent magnet 36, the magnetic field generated by the permanent magnet 36 on the side where the fixed contactor 51 is installed can be stronger than the magnetic field generated by the permanent magnet 36 on the side opposite the side where the fixed contactor 51 is installed.

[0042] FIG. 16 is a diagram illustrating the contact opening operation of a switchgear according to embodiment 6. When an arc 70 generated during the contact opening operation approaches the rod-shaped member 39, the arc 70 is captured by the magnetic field of the permanent magnet 36. The magnetic field lines emanating from the permanent magnet 36 and passing through the rod-shaped member 39 include a component that intersects with the arc 70 generated between the moving contact 31 and the fixed contact 51, causing the arc 70 to rotate within the magnetic field generated by the permanent magnet 36. In FIG. 16 , the arc 70 captured by the magnetic field generated by the permanent magnet 36 is drawn in while rotating, moving from position B to position C, and then from position C to position D. During the contact opening operation, the arc 70 generated between the moving contact 31 and the fixed contact 51 is drawn into the moving contact 31 while rotating, and is thereby stretched, cooled, and extinguished.

[0043] The opening and closing device 100 according to the sixth embodiment generates a gas flow at the fixed side opening of the movable contactor 31 that includes a radial component that is perpendicular to the axial direction of the central axis of the movable contactor 31, and further improves the extinguishing performance of the arc 70 by elongating the arc 70 using the magnetic field generated by the permanent magnet 36.

[0044] In the switchgear 100 according to the sixth embodiment, the cross-flow forming part 42 may be shaped like a teardrop or a pinwheel. When the cross-flow forming part 42 is shaped like a pinwheel, the switchgear 100 is used to interrupt DC current, and the rotation direction of the arc 70 due to the magnetic field generated by the permanent magnet 36 is opposite to the rotation direction of the gas flow due to the cross-flow forming part 42. This makes it possible to blow low-temperature insulating gas that is not heated by the arc 70 as a gas flow onto the arc 70, thereby further improving the arc-extinguishing performance.

[0045] The configurations shown in the above embodiments are merely examples of the content, and may be combined with other known technologies, or parts of the configurations may be omitted or modified without departing from the spirit of the invention.

[0046] 1 Sealed container, 3 Movable electrode, 5 Fixed electrode, 11 Area, 31 Movable contact, 32 Cylinder, 33 Piston, 34 Rod, 35 Support base, 36 Permanent magnet, 38 Lid, 39 Rod-shaped member, 40 Insulating layer, 41 Puffer chamber, 42, 313 Cross-flow forming portion, 43 Cap, 51 Fixed contact, 60 Nozzle portion, 70 Arc, 100 Switching device, 311 First portion, 312 Second portion, 312a Ventilation hole, 351 Holding portion, 351a, 421, 431 Outer circumferential surface, 352 Support leg, 371 First cylinder, 372 Second cylinder, 422, 432 End, 423 Groove, 424 Side.

Claims

1. A sealed container filled with insulating gas; A fixed electrode installed inside the sealed container; a movable electrode having a cylindrical cylinder, a piston installed in the cylinder, and a movable contactor having a smaller diameter than the cylinder and fixed to the piston, the movable electrode being installed movably inside the sealed container, the movable contactor having an air hole formed therein connecting a puffer chamber, which is a space formed between the cylinder and the movable contactor, to a space inside the movable contactor; a cross flow forming section that causes a gas flow drawn into the movable contactor during an opening operation in which the movable electrode transitions from a closed state in which the movable electrode is in contact with the fixed electrode to an open state in which the movable electrode is separated from the fixed electrode to include a component in a direction perpendicular to a central axis of the movable contactor, A switching device, characterized in that the cross-flow forming portion is disposed on a central axis of the movable contact.

2. A support stand installed in the movable contact; a rod-shaped member disposed adjacent to the support base on a side on which the fixed electrode is disposed, The opening and closing device according to claim 1 , wherein the cross-flow forming portion is provided at a tip of the rod-shaped member.

3. A permanent magnet is fixed to the support base, The opening and closing device according to claim 2 , wherein the rod-shaped member is made of a magnetic material.

4. 4. The switching device according to claim 1, wherein the cross-flow forming portion has a shape whose diameter increases along a direction from the movable electrode to the fixed electrode in an axial direction of a central axis of the movable contactor.

5. 4. The opening and closing device according to claim 1, wherein the cross-flow forming portion has a teardrop shape when viewed from a direction perpendicular to the axial direction of the movable contact.

6. 4. The opening and closing device according to claim 1, wherein the cross-flow forming portion is in the shape of a windmill having an inclined surface whose position around the axis changes along the axial direction of the central axis of the movable contact.

7. A sealed container filled with an insulating gas; A fixed electrode installed inside the sealed container; a movable electrode having a cylindrical cylinder, a piston installed in the cylinder, and a movable contactor having a smaller diameter than the cylinder and fixed to the piston, the movable electrode being installed movably inside the sealed container, the movable contactor having an air hole formed therein connecting a puffer chamber, which is a space formed between the cylinder and the movable contactor, to a space inside the movable contactor; a cross flow forming section that causes a gas flow drawn into the movable contactor during an opening operation in which the movable electrode transitions from a closed state in which the movable electrode is in contact with the fixed electrode to an open state in which the movable electrode is separated from the fixed electrode to include a component in a direction perpendicular to a central axis of the movable contactor, The switching device, wherein the cross-flow forming portion has a teardrop shape when viewed from a direction perpendicular to the axial direction of the movable contact.

8. A sealed container filled with an insulating gas; A fixed electrode installed inside the sealed container; a movable electrode having a cylindrical cylinder, a piston installed in the cylinder, and a movable contactor having a smaller diameter than the cylinder and fixed to the piston, the movable electrode being installed movably inside the sealed container, the movable contactor having an air hole formed therein connecting a puffer chamber, which is a space formed between the cylinder and the movable contactor, to a space inside the movable contactor; a cross flow forming section that causes a gas flow drawn into the movable contactor during an opening operation in which the movable electrode transitions from a closed state in which the movable electrode is in contact with the fixed electrode to an open state in which the movable electrode is separated from the fixed electrode to include a component in a direction perpendicular to a central axis of the movable contactor, A switching device, characterized in that the cross-flow forming portion is in a windmill shape having an inclined surface whose position around the axis changes along the axial direction of the central axis of the movable contact.