Opening / closing device

Abstract

An opening / closing device of the present disclosure comprises: a main circuit that is formed in a reversed C-shape with an upper terminal (4), a fixed electrode (2), a movable electrode (3), a movable electrode (3), and a lower terminal (5s); and a support body 6 that supports a movable electrode rod (3b). The opening / closing device is configured such that the position of an electrical connection to the movable electrode rod (3b) and the position at which the support body (6) supports the movable electrode rod (3b) are set at the position where a forward moment (Mcw) and a reverse moment (Mccw), which cause the movable electrode rod (3b) to rotate by means of an electromagnetic force generated in accordance with the electric current flowing through the main circuit, are balanced.

Description

Switchgear

[0001] The present disclosure relates to a switching device.

[0002] In a switching device that uses a vacuum valve to open and close an electrical circuit in a vacuum, for example, in order to open and close a large current, the movable contact moves linearly relative to the fixed contact, so the vacuum valve in the main circuit and the paths before and after it are configured in a U-shape.

[0003] In such switching devices, especially when they have a short-time withstand current duty, the closed state is maintained by applying a force such as spring compression to the moving contact of the vacuum interrupter pressing against the fixed contact. However, when a large current such as a short-circuit current flows in the closed state, an electromagnetic force acts on the moving contact, and if this electromagnetic force exceeds the frictional force between the contacts caused by the spring compression, the moving contact will move in the direction of the electromagnetic force, causing the contacts to separate and generating an arc, which may lead to the contacts welding together.

[0004] In response to this, an opening and closing device has been disclosed in which a protrusion extending in the direction of the electromagnetic force is provided on an insulating frame or a guide of a vacuum valve, and the protrusion braces against the electromagnetic force, thereby suppressing the movement of the movable electrode rod (see, for example, Patent Document 1).

[0005] JP 2008-108443 A (paragraphs 0013-0014, Figure 1)

[0006] However, it has been found that there are cases where the movement of the movable electrode rod cannot be suppressed simply by stretching it against the movement in the direction of the electromagnetic force.

[0007] The present application discloses a technique for solving the above-mentioned problems, and aims to provide a highly reliable switchgear in which the movement of the movable electrode rod is suppressed.

[0008] The switching device disclosed in the present application comprises a fixed electrode having a fixed contact at one end, a movable electrode having a movable contact at one end of a movable electrode rod, the movable contact facing the fixed contact being able to be brought into contact with and separated from the fixed contact by driving the movable electrode rod along the extension direction, a first terminal connected to the other end of the fixed electrode and extending in a first direction perpendicular to the extension direction, a second terminal electrically connected to a first position in an intermediate portion of the movable electrode rod along the extension direction and extending in the first direction, and a support body that supports the movable electrode rod from the first direction side at a second position between the first position and the movable contact, and is characterized in that the first position and the second position are set at positions where a positive moment and a negative moment that rotate the movable electrode rod around the second position in a plane including the extension direction due to an electromagnetic force generated in response to a current flowing in a main circuit from the first terminal to the second terminal are balanced.

[0009] According to the opening and closing device disclosed in the present application, the position of the support and the electrical connection position are set so as to maintain moment balance, thereby reliably suppressing the movement of the movable electrode rod and obtaining a highly reliable opening and closing device.

[0010] 2A and 2B are a side view of an opening / closing mechanism portion of a switching device according to the first embodiment. FIGS. 2A and 2B are a plan view of a peripheral portion of a support of the switching device according to the first embodiment, and a cross-sectional view of the support. FIGS. 2A and 2B are a side view of the periphery of the support of the switching device according to the comparative example. FIGS. 2B and 2C are a side view of the periphery of the support of the switching device according to the first modified example of the first embodiment. FIGS. 5A and 5B are a plan view of the periphery of the support of the switching device according to the first modified example of the first embodiment, and a cross-sectional view of the support. FIGS. 6A and 6B are a side view of the periphery of the support of the switching device according to the second modified example of the first embodiment, and a side view of the periphery of the support of the switching device according to the third modified example, respectively. FIGS. 7A and 7B are a plan view of a support of the switching device according to the second embodiment, and a plan view of a support of the switching device according to the modified example, respectively. FIGS. 7B and 7C are a side view showing a state during assembly of the opening / closing mechanism portion of the switching device according to the second embodiment. FIGS. 10A and 10B are a plan view of a support of the switching device according to the third embodiment, and a plan view of a support of the switching device according to the modified example, respectively.

[0011] 1 to 3 are diagrams for explaining the configuration and operation of a switching device according to a first embodiment, in which Fig. 1 is a side view of the switching mechanism portion of the switching device, with a part of the vacuum valve cut away so that the contact portion can be seen, Fig. 2A is a plan view of the surrounding portion of the support, and Fig. 2B is a cross-sectional view of the support taken along line A-A in Fig. 2A. Also, Fig. 3 is a side view of the surrounding portion of the support of a switching device according to a comparative example, taken in the same direction as Fig. 1.

[0012] 4 to 5B are diagrams for explaining the configuration and operation of an opening / closing device according to a first modified example of embodiment 1, with Fig. 4 being a side view of the opening / closing mechanism portion corresponding to Fig. 1, Fig. 5A being a plan view of the support periphery corresponding to Fig. 2A, and Fig. 5B being a cross-sectional view of the support taken along line B-B in Fig. 5A. Fig. 6A is a side view of the support periphery of an opening / closing device according to a second modified example, and Fig. 6B is a side view of the support periphery of an opening / closing device according to a third modified example, and the depiction directions correspond to Fig. 1. Note that in this specification, the positive side is expressed as up, the z direction as the up-down direction, the positive side as the front, the x direction as the front-to-back direction, and the y direction as the left-to-right direction, but it goes without saying that these may differ from the actual installation state.

[0013] 1, the switchgear according to the first embodiment includes a fixed electrode 2 having a fixed contact 2j formed on one end of a fixed electrode rod 2b, and a movable electrode 3 having a movable contact 3j formed on one end of a movable electrode rod 3b, which are aligned in a straight line in the vertical direction (z direction) so that the fixed contact 2j and the movable contact 3j face each other. The switchgear also includes a switchgear operation mechanism 11 that is supported by a housing (not shown) and that mechanically supports the other end 3e of the movable electrode 3 via an insulating rod 10. Therefore, when the switchgear operation mechanism 11 is operated, the movable electrode 3 moves in the vertical direction, and the movable contact 3j moves in contact with and away from the fixed contact 2j, thereby performing an opening and closing operation.

[0014] The arc-extinguishing unit, which performs the opening and closing operation in a vacuum atmosphere, is equipped with a vacuum valve 1 that hermetically (vacuum) houses the portion of the fixed electrode rod 2b on the fixed contact 2j side and the portion of the movable electrode rod 3b on the movable contact 3j side. The other end of the fixed electrode rod 2b protruding from the vacuum valve 1 is electrically connected to an upper terminal 4 extending rearward (to the negative side in the x direction). The middle portion of the movable electrode rod 3b is electrically connected via a flexible conductor 5f to a standard lower terminal 5s (together forming a lower current-carrying unit 5) that extends rearward in the same manner as the upper terminal 4. As a result, when the fixed contact 2j and the movable contact 3j are brought into contact and closed, the current path (main circuit configuration) from the upper terminal 4 to the lower terminal 5s becomes U-shaped and opens rearward in the xz plane.

[0015] The upper end of the vacuum valve 1, together with the upper terminal 4, is mechanically fixed to the partition wall 7c of the insulating frame 7, which is fixed to the housing, and the lower terminal 5s is mechanically fixed by fastening members 8 to a beam 7g extending in the left-right direction of the insulating frame 7. Meanwhile, an electrode rod guide 1g that slidably holds the movable electrode rod 3b is formed on the lower end of the vacuum valve 1, allowing the movable electrode rod 3b to move up and down while maintaining the internal vacuum. Furthermore, to prevent the movable contact 3j from separating from the fixed contact 2j in the closed state, the insulating rod 10 is structured to press the movable contact 3j against the fixed contact 2j via the movable electrode rod 3b using a pressure spring 10s or the like.

[0016] The configuration up to this point is similar to that of a general switchgear, but before explaining the characteristic configuration of the switchgear of the present disclosure, the operation and problems of a general switchgear will be explained. Note that, in the following, a switchgear using a vacuum valve 1 called a vacuum circuit breaker as a component having a switching function will be explained as an example, but the switchgear is not limited to a vacuum circuit breaker as long as the component having the switching function and the paths before and after it are configured in a U-shape and have a short-time withstand current duty.

[0017] If a switchgear has short-time current resistance, it must be able to open and close without impairing its performance even after a large current, such as a short-circuit current, flows through the switchgear. On the other hand, as mentioned above, if the main circuit structure of the switchgear is U-shaped, the current flowing through the vacuum interrupter 1 is subjected to an electromagnetic force according to Fleming's law from the magnetic field generated by the current flowing through the upper terminal 4 and the lower terminal 5s. This force acts in a direction that causes the contacts to slip from the closed state, where the movable contact 3j is pressed against the fixed contact 2j via the movable electrode rod 3b. Therefore, when a large current, such as a short-circuit current, flows through the main circuit, this electromagnetic force becomes large enough to overcome the frictional force acting between the contacts, causing slippage and possible separation. If this separation occurs, an arc will occur between the contacts, resulting in welding and an inability to open the contacts.

[0018] Here, it was found that although the protrusion in Patent Document 1 can resist the electromagnetic force directed forward as indicated by the arrow in Fig. 1, there are cases where this alone is not enough to suppress the movement of the movable electrode rod. Therefore, as a comparative example, a prototype opening and closing device was produced in which the electrode rod guide provided at the bottom of the vacuum interrupter 1X was fixed with a fixing device 6X as shown in Fig. 3, and cases in which movement occurs were examined.

[0019] As a result, it was found that in cases where misalignment occurred between the contacts, the movable electrode rod 3bX rotated around the position of the fixture 6X in the z direction as the fulcrum Pp. Further analysis revealed that the greater the difference between the length Ljp of the upper part of the movable electrode rod 3bX from the fulcrum Pp to the contact and the length Lep of the lower part from the fulcrum Pp to the electrical connection point with the flexible conductor 5fX, the easier the rotational movement became. Note that parts of the switching device according to the comparative example that correspond to those of the switching device according to the present disclosure are distinguished by adding "X" to the end of the same reference numerals.

[0020] For example, when a forward-directed self-phase electromagnetic force is applied to the movable electrode rod 3bX, a positive moment Mcw acts on the upper part of the movable electrode rod 3bX, tending to move it clockwise around the fulcrum Pp in the zx plane, and a reverse moment Mcw acts on the lower part of the movable electrode rod 3bX, tending to move it counterclockwise. It was found that when this balance is lost, the movable electrode rod 3bX is prone to rotational motion around the fulcrum Pp.

[0021] Therefore, in the switchgear of the present disclosure, the electrical connection position to the movable electrode bar 3b and the position of the support body 6 are set so that the positive moment Mcw and the reverse moment Mcw are balanced. This suppresses the occurrence of rotational motion around the fulcrum Pp, and reliably restricts the movement of the movable electrode bar 3b. Note that, because the force that urges the movable electrode bar 3b forward is generated by the U-shaped portion extending from the upper terminal 4 to the lower terminal 5s, the position is set based on the profile of the electromagnetic force along the z direction, rather than simply making the lengths Ljp and Lep equal.

[0022] On the other hand, the electromagnetic force mentioned above is a self-phase electromagnetic force acting in the positive x direction. However, restricting movement in the positive x direction alone does not restrict slippage in the left-right direction (y direction). Furthermore, in the case of a three-phase motor, it is not possible to counteract the inter-phase electromagnetic force acting in the left-right direction.

[0023] 2A and 2B , the opening and closing device of the present disclosure is provided with a support 6 whose one end is fixed to a beam 7g by a fastening member 8 and whose other end is provided with a recess 6c having an inner diameter Dc that matches the outer diameter of the electrode rod guide 1g. As a result, when the electrode rod guide 1g fits into the recess 6c, it can resist forces (x direction: self-phase electromagnetic force, y direction, inter-phase electromagnetic force) caused by electromagnetic forces in any direction in a plane perpendicular to the up and down direction (xy plane), and can restrict slippage in any direction in the xy plane.

[0024] Furthermore, the support 6 is provided with a through-hole 6h that is continuous with the recess 6c and has an inner diameter Dh that matches the outer diameter of the movable electrode 3b. Therefore, even if the support 6 is moved downward and away from the electrode guide 1g, the through-hole 6h can restrict the movement of the movable electrode 3b in any direction within the x-y plane. In other words, even if the support 6 is moved away from the electrode guide 1g, the positive moment Mcw and the reverse moment Mccw can be balanced by adjusting at least one of the position of the support 6 and the connection position between the movable electrode 3b and the flexible conductor 5f.

[0025] This structure prevents slippage between the contacts (fixed contact 2j, movable contact 3j), making it possible to prevent contact separation even when the contact pressure load between the contacts is reduced, resulting in a more compact contact pressure spring 10s and the associated energy reduction effect. Furthermore, for example, when the contacts are made smaller to make the vacuum interrupter more compact, the amount of contact tilt increases compared to larger contacts, making contact separation more likely to occur. Therefore, the technology disclosed herein also contributes to the miniaturization of the vacuum interrupter 1 while still providing a large capacity.

[0026] First Modification. In the above example, the support 6 is provided with a recess 6c so that it can also restrict the movement of the electrode rod guide 1g provided at the bottom of the vacuum interrupter 1, but this is not limiting. For example, as shown in Figures 4, 5A, and 5B, the support 6 may be provided with a through-hole 6h having an inner diameter Dh that matches the outer diameter of the movable electrode rod 3b, without the recess 6c. In this case, although it is not possible to directly support the electrode rod guide 1g, it is possible to restrict the movement of the movable electrode rod 3b at any position in the vertical direction so that the positive moment Mcw and the reverse moment Mcw are balanced.

[0027] Alternatively, if it is not necessary to move the support 6 away from the electrode rod guide 1g when adjusting the position to balance the forward and reverse moments, the inner diameter Dh of the through hole 6h may be adjusted to match the outer diameter of the electrode rod guide 1g.

[0028] In this disclosure, an example has been shown in which the movable electrode rod 3b and the lower terminal 5s are electrically connected via the flexible conductor 5f as the lower current-carrying part 5 in order to follow the movement of the movable electrode 3, but this is not limiting and another configuration may be used as long as it does not interfere with the movement of the movable electrode 3. In this case as well, the positive moment Mcw and the reverse moment Mccw can be balanced by adjusting the connection position between the lower current-carrying part 5 and the movable electrode rod 3b when the main circuit is in the closed state and the position of the support body 6.

[0029] Second and third modified examples. In this case, the support body 6 is fastened to the beam portion 7g of the insulating frame 7 by the fastening member 8, but the fastening point is not limited to the beam portion 7g as long as the position of the support body 6 can be fixed. For example, as shown in FIG. 6A as a second modified example, the support body 6 may be fastened to the lower terminal 5s. For example, as shown in FIG. 6B as a third modified example, the support body 6 may be fastened to both the lower terminal 5s and the beam portion 7g.

[0030] In this disclosure, the beam 7g is treated as an integral part with the partition wall 7c, but this is not limiting. For example, the beam 7g and the partition wall 7c may be separate bodies, as long as the positional relationship between the support body 6 and the vacuum interrupter 1 is mechanically fixed.

[0031] Embodiment 2. In the above-described embodiment 1, an example was described in which a through-hole or a recess is provided in the support so as to restrict movement of the movable electrode rod or electrode rod guide in all directions within the xy plane. In contrast, in this embodiment 2, a configuration will be described in which the through-hole and the recess extend in one direction so as to allow movement in the negative x direction within the xy plane.

[0032] 7A to 9 are diagrams for explaining the configuration and operation of the opening and closing device according to the second embodiment, in which Fig. 7A is a plan view of the support corresponding to Fig. 2A, Fig. 7B is a plan view of the support corresponding to Fig. 5A of the opening and closing device according to the modified example, Fig. 8 is a side view corresponding to Fig. 1 showing a state during assembly of the opening and closing mechanism part of the opening and closing device, and Fig. 9 is a side view showing another state during assembly.

[0033] In the support body 6 of the switchgear according to the second embodiment, the circular recesses 6c and through-holes 6h that surround the electrode rod guide 1g and the movable electrode rod 3b on all four sides in the first embodiment have been changed to oval shapes extending in the front-to-rear direction, as shown in Fig. 7A. The support body 6 is fixed when the electrode rod guide 1g and the movable electrode rod 3b are at the front-most positions of the recesses 6c and through-holes 6h.

[0034] In this case, the electrode rod guide 1g and the movable electrode rod 3b are allowed to move backward. However, because the electromagnetic force acting on the movable electrode rod 3b and the direction in which it can slide are only forward and left and right, the backward movement is minor in terms of contact between the contacts. In other words, there is no problem in suppressing the movement of the movable electrode rod 3b when the switchgear is in operation.

[0035] On the other hand, by changing the recess 6c and the through hole 6h to an oval shape extending in the front-to-rear direction (x direction), before the support body 6 is fixed in the switchgear, it is possible to move the support body 6 in the front-to-rear direction within the main circuit single-pole of the switchgear, as shown in Fig. 8. When assembling the switchgear, it is generally easier to assemble the single-pole unit outside the insulating frame 7 and then insert it into the insulating frame 7, rather than assembling the single-pole unit from the upper terminal 4 to the insulating rod 10 within the insulating frame 7.

[0036] However, when the recess 6c or through-hole 6h is circular as in the first embodiment, the support 6 and the insulating frame 7 (particularly the beam 7g) may interfere with each other during insertion, making it impossible to insert the circuit board. However, the support 6 in the second embodiment can move within the single-pole unit, so that the position of the support 6 can be brought closer to the vacuum interrupter 1 as shown in Figure 9 when the single-pole is inserted into the insulating frame 7, reducing the possibility of interference with the insulating frame 7 and improving the ease of assembly of the switchgear.

[0037] As shown in Fig. 7B, even if the recess 6c is not provided and the through-hole 6h is oval, the effect of improving the ease of assembly can be achieved without interfering with the suppression of the movement of the movable electrode rod 3b when the switching device is in operation, as in the embodiment described in Fig. 7A.

[0038] Third Embodiment In a switching device according to a third embodiment, an example will be described in which a slit is provided from the front or rear of the support body to reach the through-hole. Figures 10A and 10B are diagrams for explaining the configuration and operation of a switching device according to the third embodiment, with Figure 10A being a plan view of the support body of the switching device corresponding to Figure 2A, and Figure 10B being a plan view of the support body of a switching device according to a modified example corresponding to Figure 10A. Note that apart from providing a slit in the support body, this is the same as in the first embodiment, and Figure 1 of the first embodiment is used here.

[0039] In the opening and closing device according to the third embodiment or the opening and closing device according to the modified example, as shown in Fig. 10A, a slit 6s is provided that has a width narrower than the outer diameter Dh of the through hole 6h and passes through the through hole 6h from the rear. Even if the slit 6s causes a portion of the electrode rod guide 1g or the movable electrode rod 3b not to come into contact with the electrode rod guide 1g or the movable electrode rod 3b, the electrode rod guide 1g or the movable electrode rod 3b can be supported by the inner surface of the through hole 6h or the recess 6c adjacent to the slit 6s. Therefore, there is no significant impact on support performance.

[0040] Here, since the support 6 is intended for mechanical fixation, it is assumed that iron or the like, which is cheaper than the material (conductive material) used in the current-carrying portion of the main circuit, is used. However, steel materials such as iron have a higher magnetic permeability than conductive materials (1×10 -3H / m or more). On the other hand, in order to make the support 6 such as the lower terminal 5s have the same potential as the main circuit, the support 6 is electrically connected to a conducting part (lower conducting part 5) such as the lower terminal 5s via, for example, a fastening member 8. Here, if the conducting material constituting the conducting part is a material with low magnetic permeability such as copper (1×10 -5 Even if the magnetic permeability is less than 100 MPa (H / m), if a closed loop is formed around the movable electrode rod 3b using a material with high magnetic permeability (support 6), a magnetic circuit will be formed in that portion. However, by providing a slit 6s to cut the closed loop, the formation of a magnetic circuit can be prevented.

[0041] For example, if a closed loop surrounding the movable electrode bar 3b is formed using a material with high magnetic permeability that constitutes the support 6, the current flowing through the movable electrode bar 3b will pass through the inside of the closed loop of the support 6, and the current will be linked to the support 6. As a result, the magnetic field Mf generated by the current will penetrate the support 6, and an induced current will be generated in the support 6. Heat generated by this induced current will have an adverse effect on the performance of the switchgear, so this heat generation should be reduced as much as possible.

[0042] The induced electromotive force is determined by the change in magnetic flux over time, and this change in magnetic flux over time is proportional to the magnetic permeability of the material through which the magnetic flux passes. Therefore, if a magnetic circuit is made up only of materials with high magnetic permeability, the induced electromotive force will be large, leading to an increase in the induced current and the resulting heat generation. As mentioned above, in order to make the support 6 have the same potential as the main circuit, the support 6 is connected to the lower current-carrying part 5, such as the lower terminal 5s, via the fastening member 8, which is a conductive material.

[0043] Here, if the lower current-carrying portion 5 is made of a material with high magnetic permeability, providing the slits 6s will not reduce the magnetic permeability of the entire magnetic circuit. However, in reality, materials that have low magnetic permeability compared to steel, such as highly conductive copper and aluminum, are used for components that make up the main circuit, such as the lower current-carrying portion 5. Therefore, by providing the slits 6s so as to break the formation of a closed loop made up of the highly permeable material that makes up the support 6, the magnetic permeability of the magnetic circuit can be reduced, which will lead to a reduction in induced electromotive force and the amount of heat generated by induced current.

[0044] The slits 6s are provided to prevent the support 6 from forming a magnetic circuit, and the slit position may be different from that shown in Figure 10A as long as sufficient support performance for the movable electrode rod 3b can be ensured. For example, as shown in Figure 10B as a modified example, a slit 6s extending from the front into the through-hole 6h can also prevent the formation of a magnetic circuit. Furthermore, this can be applied to a case where the recess 6c described in Figures 5A and 5B is not used.

[0045] The slit 6s shown in the third embodiment can also be applied to the oval through-hole 6h or recess 6c shown in the second embodiment. Furthermore, when the slit 6s is provided at the rear of the through-hole 6h, the slit 6s may be provided so as to extend rearward while maintaining the width of the inner diameter Dh of the through-hole 6h instead of the oval shape. By doing so, it becomes possible, for example, to retrofit the support 6 to an assembled monopole unit.

[0046] Although various exemplary embodiments and examples are described in this disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the content disclosed in a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless modifications not illustrated are contemplated within the scope of the technology disclosed herein. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components disclosed in other embodiments.

[0047] For example, in the above example, the support 6 supports the movable electrode rod 3b from the front side and both the left and right sides, but this is not limitative. It is sufficient to support the movable electrode rod 3b from at least the front side at a position where the positive moment Mcw and the reverse moment Mcw are balanced.

[0048] As described above, the opening and closing device of the present disclosure includes a fixed electrode 2 having a fixed contact 2j at one end, a movable electrode 3 having a movable contact 3j at one end of a movable electrode rod 3b, the movable contact 3j facing the fixed contact 2j being able to be brought into contact with and separated from the fixed contact 2j by driving the movable electrode rod 3b along the extension direction (vertical direction: z direction) of the movable electrode rod 3b, a first terminal (upper terminal 4) connected to the other end of the fixed electrode 2 and extending in a first direction (negative x direction) perpendicular to the extension direction, and a second terminal (upper terminal 4) electrically connected to a first position in the middle of the extension direction of the movable electrode rod 3b and extending in the first direction. The device is provided with two terminals (lower terminal 5s) and a support 6 that supports the movable electrode rod 3b from the first direction (negative x direction) side at a second position between the first position and the movable contact 3j, and is configured so that the first position and the second position are set at positions where a positive moment (positive moment Mcw) and a reverse moment (reverse moment Mcw) that rotate the movable electrode rod 3b about the second position as a fulcrum Pp in a plane (x-z plane) including the extension direction due to an electromagnetic force generated in response to a current flowing in a main circuit from the first terminal (upper terminal 4) to the second terminal (lower terminal 5s) are balanced. This makes it possible to restrict not only the translation of the movable electrode rod 3b along the x-y plane but also its rotational movement along the x-z plane, thereby suppressing separation between the contacts and obtaining a highly reliable switching device.

[0049] Furthermore, if the support 6 is configured to support the movable electrode bar 3b from both sides in a direction (y direction) perpendicular to the extension direction and perpendicular to the first direction at the second position, not only can slippage be prevented but also movement due to interphase electromagnetic forces acting in the left-right direction (y direction) in the case of a three-phase system can be countered, and the movement of the movable electrode bar 3b can be more reliably regulated.

[0050] The support body 6 has a first through hole (through hole 6h) into which the movable electrode rod 3b can be inserted as a support part for supporting the movable electrode rod 3b, so that the movable electrode rod 3b can be reliably supported from the front and both the left and right sides.

[0051] If the support portion (through hole 6h) is configured to extend along the first direction in a plane perpendicular to the extension direction (xy plane) so that the movable electrode rod 3b can move in the first direction (rearward: negative x direction), then, for example, even after assembling the single-pole unit, the support 6 can be incorporated into the device without interfering with the insulating frame 7, etc.

[0052] The support body 6 is formed of a material (e.g., iron) having a higher magnetic permeability than the second terminal (lower terminal 5s: e.g., copper), and a slit 6s is formed extending from the first through hole (through hole 6h) to the outer opening in a plane perpendicular to the extension direction (xy plane), thereby suppressing heat generation due to induced current flowing through the support body 6 and maintaining high opening and closing function.

[0053] Furthermore, if the slit 6s has a width that allows the movable electrode rod 3b to move and extends from the first through hole (through hole 6h) in the first direction (negative x direction) to the outer opening, heat generation due to induced current flowing through the support 6 can be suppressed, maintaining high opening and closing functionality, and the support 6 can be installed even after the single-pole unit is incorporated into the device.

[0054] A vacuum valve 1 is provided which houses a fixed contact 2j and a movable contact 3j in a vacuum atmosphere, and the support body 6 is provided with either a first through hole (through hole 6h) into which the movable electrode rod 3b can be inserted, a second through hole into which an electrode rod guide 1g provided on the vacuum valve 1 can be inserted, or a combination of a recess 6c into which the electrode rod guide 1g can be fitted and the first through hole (through hole 6h), so that even in an opening and closing device using the vacuum valve 1, not only the parallel movement of the movable electrode rod 3b along the xy plane but also its rotational movement along the xz plane can be restricted, thereby suppressing separation between the contacts and obtaining a highly reliable opening and closing device.

[0055] In this case, if any of the support parts is configured to extend along the first direction (negative x direction) in a plane perpendicular to the extension direction (xy plane) so that the movable electrode rod 3b or electrode rod guide 1g can move in the first direction (negative x direction), then, for example, even after assembling a single-pole unit including the vacuum valve 1, the support 6 can be incorporated into the device without interfering with the insulating frame 7, etc.

[0056] The support body 6 is formed of a material (e.g., iron) having a higher magnetic permeability than the second terminal (lower terminal 5s: e.g., copper), and by forming a slit 6s extending from the first through hole (through hole 6h) or the second through hole to an outer opening in a plane perpendicular to the extension direction (xy plane), heat generation due to induced current flowing through the support body 6 can be suppressed, thereby maintaining high opening and closing function.

[0057] In this case, if the slit 6s has a width that allows the movable electrode rod 3b or electrode rod guide 1g to move and extends from the first through hole (through hole 6h) or the second through hole in the first direction (negative x direction) to the outer opening, heat generation due to induced current flowing through the support 6 can be suppressed, maintaining high opening and closing functionality, and the support 6 can be installed even after a single-pole unit using the vacuum valve 1 has been incorporated into the device.

[0058] 1: vacuum valve, 1g: electrode rod guide, 2: fixed electrode, 2j: fixed contact, 3: movable electrode, 3b: movable electrode rod, 3j: movable contact, 4: upper terminal, 5: lower current-carrying part, 5f: flexible conductor, 5s: lower terminal, 6: support, 6c: recess, 6h: through hole, 6s: slit, 7: insulating frame, 7c: partition part, 7g: beam part, 8: fastening member, 10: insulating rod, 10s: contact pressure spring, 11: switchgear operating mechanism part, Dc: inner diameter, Dh: inner diameter, Mcw: positive moment, Mcw: reverse moment, Pp: fulcrum.

Claims

1. A fixed electrode provided with a fixed contact at one end, a movable electrode having a movable contact provided at one end of a movable electrode bar, the movable contact facing the fixed contact being arranged to be able to contact and separate from the fixed contact by driving along the extending direction of the movable electrode bar, a first terminal connected to the other end of the fixed electrode and extending in a first direction perpendicular to the extending direction, a second terminal electrically connected to a first position in an intermediate portion of the movable electrode bar along the extending direction and extending in the first direction, and a support supporting the movable electrode bar from the side in the first direction at a second position between the first position and the movable contact, and the first position and the second position are set at a position where a positive moment and a negative moment for rotating the movable electrode bar in a plane including the extending direction around the second position as a fulcrum by an electromagnetic force generated according to a current flowing in a main circuit from the first terminal to the second terminal are balanced. An opening / closing device characterized by this.

2. The opening / closing device according to claim 1, wherein the support supports the movable electrode bar from both sides in a direction perpendicular to the extending direction and perpendicular to the first direction at the second position.

3. The opening / closing device according to claim 2, wherein the support is provided with a first through hole into which the movable electrode bar can be inserted as a support portion for supporting the movable electrode bar.

4. The opening / closing device according to claim 3, wherein the support portion extends along the first direction in a plane perpendicular to the extending direction so that the movable electrode bar can move in the first direction.

5. The support is formed of a material having a higher magnetic permeability than a conductive member constituting the second terminal, and a slit extending from the first through hole to an outer opening in a plane perpendicular to the extending direction is formed. The opening / closing device according to claim 3 or 4, characterized by this.

6. The opening / closing device according to claim 5, wherein the slit has a width through which the movable electrode bar can move and extends from the first through hole to the outer opening in the first direction.

7. The opening / closing device according to claim 2, further comprising a vacuum valve that houses the fixed contact and the movable contact in a vacuum atmosphere, wherein the support body is provided with any one of a first through-hole into which the movable electrode bar can be inserted, a second through-hole into which an electrode bar guide provided in the vacuum valve can be inserted, and a combination of a recess into which the electrode bar guide can be fitted and the first through-hole, as a support portion for supporting the movable electrode bar.

8. The opening / closing device according to claim 7, wherein the support portion extends along the first direction in a plane perpendicular to the extending direction so that the movable electrode bar or the electrode bar guide can move in the first direction.

9. The opening / closing device according to claim 7 or 8, wherein the support body is formed of a material having a higher magnetic permeability than the conductive member constituting the second terminal, and a slit is formed extending from the first through-hole or the second through-hole to an outer opening in a plane perpendicular to the extending direction.

10. The opening / closing device according to claim 9, wherein the slit has a width that allows the movable electrode bar or the electrode bar guide to move and extends from the first through-hole or the second through-hole to the outer opening in the first direction.

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