Storage boxes and opening and closing devices

Abstract

Obtained in the present invention are a storage box and an opening / closing device that make it possible to reduce the weight of the storage box while also preventing foreign matter from entering the storage box.　A storage box (91) houses an opener / closer (100), and has a pressure release hole (91c) provided to a side wall for releasing internal pressure, and a pressure release device (10) attached to the (side wall 91c). The pressure release device (10) is provided with: a pressure release plate (11) comprising a movable part (11c) which is capable of moving between a sealed position for sealing the pressure release hole (91c) and an open position for opening the pressure release hole (91c); and a deformable part (11b) that is elastically deformable and deforms according to the movement of the movable part (11c). When the movable part (11c) is at the open position, a load is applied, due to the elastic force of the deformable part (11b), to the movable part (11c) in a direction of return to the sealed position.

Description

[Technical field]

[0001] The present application relates to a storage box and an opening and closing device. [Background technology]

[0002] The switchgear includes a switch and a storage box such as a protective box that stores the switch and prevents the switch from being exposed to foreign objects such as rain or dust. The storage box is configured to have high airtightness to prevent foreign objects from entering the inside. On the other hand, since there is a possibility that the pressure inside the storage box will rise due to arcing when the current is interrupted, a pressure relief device for preventing the pressure rise when the current is interrupted is provided in the storage box. The pressure relief device is configured to prevent a sudden pressure rise inside the storage box by releasing the gas inside the storage box to the outside when the current is interrupted while maintaining the airtightness of the storage box except when the current is interrupted. As a configuration for realizing such a pressure relief device, a pressure relief structure is disclosed that includes a pressure relief hole formed in the storage box and a pressure relief lid that opens the pressure relief hole when the current is interrupted and seals the pressure relief hole except when the current is interrupted (for example, see Patent Document 1). In the pressure relief structure of Patent Document 1, an O-ring attachment member is provided around the pressure relief hole to form a convex shape, and the pressure relief lid is configured to be concave so as to cover the pressure relief hole including the O-ring attachment member. The pressure release lid transitions between an open position and a closed position by utilizing the relationship between the elastic force of the torsion coil spring and the rise in internal pressure when the current is interrupted. The pressure release lid is further provided with a locking member for holding the lid in the closed position. The pressure release lid is held in the closed position by locking the locking member with a locking member provided in the pressure release hole, thereby preventing the intrusion of foreign matter into the storage box. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-263944 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the pressure relief structure of Patent Document 1, the mass of the pressure relief lid is increased compared to a pressure relief plate composed of only a simple plate-like member due to the concave shape and the attachment of the locked member. As a result, a greater gravity acts on the pressure relief lid. Since the gravity acting on the pressure relief lid acts in a direction that delays the movement of the pressure relief lid from the closed position to the open position, the pressure relief lid in Patent Document 1 takes a longer time to move from the closed position to the open position when the current is interrupted. When the time from the current interruption to the pressure relief is extended, the strength of the storage box needs to be increased to prepare for the pressure rise during that time, but the increased strength leads to a more complicated structure of the storage box and an increase in the weight of the storage box.

[0005] The present application discloses technology for solving the above-mentioned problems, and aims to provide a storage box and an opening and closing device that can reduce the weight of the storage box while preventing foreign objects from entering the storage box. [Means for solving the problem]

[0006] The storage box disclosed in the present application is a storage box that stores a switch, has a pressure relief hole in a side wall for relieving internal pressure, and has a switch pressure relief device attached to the side wall, the switch pressure relief device including a movable part that is movable between a sealed position for sealing the pressure relief hole and an open position for opening the pressure relief hole, and a deforming part that is elastically deformable and deforms in accordance with the movement of the movable part; The movable and deformable parts of the pressure relief plate are made of an elastically deformable resin material, The elastic force of the deformation part is such that when the movable part is in the open position, a load is applied to the movable part in the direction in which it returns to the closed position. The movable portion automatically returns from the open position to the closed position where no elastic force is generated in the deformed portion. It is something.

[0007] Another embodiment of the storage box disclosed in the present application is a storage box that stores a switch, has a pressure relief hole in a side wall for relieving internal pressure, and has a switch pressure relief device attached to the side wall, and the switch pressure relief device has a movable part that rotates around one end as a central axis and is movable between a sealed position where the pressure relief hole is sealed and an open position where the pressure relief hole is opened. The top corners of the side walls are cut off.The pressure relief plate comprises a pressure relief plate, a support fixed to the side walls on both sides in the direction of the central axis, a shaft supported by the support through a through hole provided in the support, and a torsion coil spring fixed to the shaft and applying a load to the movable part in a direction to maintain the movable part in the sealed position when the movable part is in the sealed position, and applying a load to the movable part in a direction to return to the sealed position when the movable part is in the open position.The pressure relief plate has a flat plate-shaped portion and an arm provided at one end of the plate-shaped portion with a hole into which the shaft fits, and the entire plate rotates together with the shaft. Effect of the Invention

[0008] According to the storage box disclosed in the present application, it is possible to reduce the weight of the storage box while preventing foreign objects from entering the storage box. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a switching device according to a first embodiment. [Diagram 2] FIG. 2 is a front view of the pressure relief device according to the first embodiment. [Diagram 3] FIG. 2 is an exploded view of components of the pressure relief device according to the first embodiment. [Figure 4A] FIG. 2 is a front view of the pressure relief plate according to the first embodiment. [Figure 4B] 6 is a front view showing another example of the pressure release plate according to the first embodiment. FIG. [Figure 4C] 6 is a front view showing another example of the pressure release plate according to the first embodiment. FIG. [Diagram 5] FIG. 2 is a perspective view illustrating a fixing method of the torsion coil spring according to the first embodiment. [Figure 6] 2 is a cross-sectional view taken along line AA of the pressure release device in the first embodiment, showing a state in which the pressure release plate is in a sealed position. FIG. [Figure 7] 2 is a cross-sectional view taken along line AA of the pressure release device in the first embodiment, showing a state in which the pressure release plate is in an open position. FIG. [Figure 8] 13A and 13B are diagrams illustrating the return operation of the pressure relief plate. [Figure 9]11 is a cross-sectional view taken along line AA of the pressure relief device in the second embodiment, showing a state in which the pressure relief plate is in a sealed position. FIG. [Figure 10] 11 is a cross-sectional view taken along line AA of the pressure release device in the second embodiment, showing a state in which the pressure release plate is in an open position. FIG. [Figure 11] FIG. 11 is a cross-sectional view taken along line AA of the pressure relief device according to the third embodiment. [Figure 12] FIG. 13 is a front view of a pressure relief device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Embodiment 1 The first embodiment will be described with reference to Figs. 1 to 8. Fig. 1 is a perspective view of a switchgear in the first embodiment. The switchgear 1000 includes, for example, a power switch 100 and a storage box 91, such as a protective box, that stores the switch. The storage box 91 is, for example, a two-tiered box, with a high airtightness to prevent foreign matter from entering the inside. For the sake of explanation, the coordinate axes are set as follows. That is, the vertical direction is the z-axis, and the x-axis and y-axis are set in a direction perpendicular to the z-axis, i.e., in the horizontal direction. The x-axis is set in a direction along the long side of the storage box 91, and the y-axis is set in a direction along the short side of the storage box 91. The upward direction of the z-axis is set as the +z-axis direction, and the downward direction is set as the -z-axis direction. As for the x-axis and y-axis, one side is set as the +x-axis direction and the +y-axis direction, and the opposite direction is set as the -x-axis direction and the -y-axis direction, as shown in Fig. 1. Direction The upper portion 91A of the storage box has a trapezoidal cross section so that the upper side is narrower. However, the shape of the storage box 91 is not limited to that shown in FIG.

[0011] In the upper portion 91A, the pressure release devices 10A and 10B, i.e., the pressure release devices of the switch, are attached to the outer surface of the side wall 91Aa along the short side direction (y-axis direction). Although not shown in FIG. 1, pressure release holes are provided at the positions where the pressure release devices are attached in the side wall 91Aa. In FIG. 1, the pressure release devices are attached in pairs, one on each side wall 91Aa on both sides, but the number and attachment positions of the pressure release devices to be attached are not particularly limited. The pressure release device 10 may be attached to the side wall 91Ab along the long side direction (x-axis direction) of the storage box 91. In the lower portion 91B, the side wall 91Bb along the long side direction (x-axis direction) is provided with a hole (not shown) through which the bus bar 92 passes. In the following description, the pressure relief device 10A will be taken as an example.

[0012] Fig. 2 is a front view of the pressure release device in the first embodiment, and is a view of the pressure release device 10A as seen in the +x-axis direction of Fig. 1. The same is true for the pressure release device 10B, and therefore will be simply described as the pressure release device 10 hereinafter.

[0013] The pressure release device 10 is attached to a pressure release device attachment portion 91d provided at a predetermined position of the side wall 91Aa. The position and range of the pressure release device attachment portion 91d are not particularly limited as long as it includes the pressure release hole 91c formed in the side wall 91Aa and can form a screw hole or the like required for attaching the pressure release device 10. The pressure release device 10 is configured to include a pressure release plate 11 covering the pressure release hole 91c, a cover 12 covering the pressure release plate 11, and two plate-like members arranged on both sides of the movable part 11c of the pressure release plate 11 in the y-axis direction, and is equipped with a support body 13 fixed to the pressure release device attachment portion 91d, a shaft 14 penetrating a through hole 13aa provided in the support body 13, and a torsion coil spring 15 of a double torsion shape attached to the shaft 14. In FIG. 2, the pressure release hole 91c is two circular holes provided adjacent to each other, but the shape and number of the pressure release holes 91c are not limited to this and can be provided arbitrarily.

[0014] The pressure release plate 11 has the same external shape as the cover 12, and is configured to prevent a gap from occurring between the cover 12 and the pressure release device mounting portion 91d when it is attached to the pressure release device mounting portion 91d together with the cover 12. The pressure release plate 11 is provided with a U-shaped slit 11a, and a movable movable portion 11c is provided in the area surrounded by the U-shaped slit 11a. The movable portion 11c moves between a sealing position where it is in close contact with the side wall 91Aa to seal the pressure release hole 91c, and an opening position where it is separated from the side wall 91Aa to open the pressure release hole 91c, and is normally in the sealing position. For this reason, the position and range of the movable portion 11c must be configured to at least be able to seal the pressure release hole 91c. A more detailed configuration of the pressure release plate 11 will be described later.

[0015] The cover 12 is attached to the pressure relief device attachment portion 91d. Although not shown in Fig. 2, the cover 12 has an opening corresponding to the movable portion 11c. In addition, a grippable handle portion 12a is integrally provided on the upper portion of the cover 12. The handle portion 12a is configured by projecting both side ends in the y-axis direction of the upper portion of the cover 12 upward and connecting the projecting portions on both sides.

[0016] The support body 13 is fixed integrally with the pressure relief plate 11 and the cover 12 to the storage box 91 by fastening members such as bolts and nuts. The shaft 14 is rotatably supported by the support body 13 by passing through the through hole 13aa. The shaft 14 is prevented from falling out of the through hole 13aa by having both axial ends interfere with the inner wall of the cover 12, thereby restricting its axial displacement. The torsion coil spring 15 has a pressing portion 15b that applies a load due to the elastic force of the torsion coil spring 15 to the movable portion 11c of the pressure relief plate 11.

[0017] FIG. 3 is an exploded view of the components of the pressure relief device in the first embodiment, and the dashed line in FIG. 3 indicates the assembly positions of the bolt 81 and nut 82, which are fastening members. As shown in FIG. 3, a hole 91e into which the bolt 81 is inserted is provided at a predetermined position of the pressure relief device mounting portion 91d. The pressure relief device 10 is mounted to the storage box 91 (pressure relief device mounting portion 91d) as follows. First, as shown in FIG. 3, the support 13 to which the torsion coil spring 15 and the shaft 14 are attached is inserted into the inside of the cover 12 from the opening 12b provided at the lower end of the cover 12 to form one component. Next, the pressure relief plate 11 is disposed so as to be sandwiched between the above components (the cover 12, the support 13, the shaft 14, and the torsion coil spring 15) and the pressure relief device mounting portion 91d, and the above components and the pressure relief plate 11 are fastened and fixed using the bolt 81 and the nut 82, thereby mounting each component to the pressure relief device mounting portion 91d. At this time, the opening 12c of the cover 12 is aligned with the movable portion 11c of the pressure release plate 11. The side surface of the cover 12 on the pressure release device mounting portion 91d side is brought into close contact with the pressure release device mounting portion 91d except for the opening 12c.

[0018] Each component attached to the pressure release device attachment portion 91d is also provided with a hole for inserting the bolt 81 at a position corresponding to the hole 91e. In addition, in the first embodiment, the pressure release device 10 is attached to the pressure release device attachment portion 91d using fastening members such as the bolt 81 and the nut 82, but an attachment method using other fixing members such as rivets may also be used.

[0019] Next, a more detailed configuration of the pressure release plate 11 will be described. FIG. 4A is a front view of the pressure release plate according to the first embodiment, and is a view of the pressure release plate 11 viewed in the +x-axis direction of FIG. 1. As described above, the pressure release plate 11 has the same external shape as the cover 12, and has an external shape with a partly recessed upper portion. A U-shaped slit 11a is provided in the center of the pressure release plate 11 in the vertical direction, and a movable portion 11c is provided in the range surrounded by the U-shaped slit 11a. A deformation portion 11b that extends in the y-axis direction and is elastically deformable is provided at the upper end of the movable portion 11c, at the opening of the U-shaped slit 11a. The movable portion 11c rotates around the y-axis with the deformation portion 11b as the deformation portion 11b elastically deforms. As a result, the movable portion 11c opens and closes like a hinge, and the movable portion 11c is movable between a closed position and an open position. The area of ​​the pressure release plate 11 other than the area surrounded by the U-shaped slit 11a is a fixed portion 11d. The fixing portion 11d has holes 11e into which bolts 81 are inserted, and is fixed to the pressure relief device mounting portion 91d by the bolts 81 and nuts 82. The positions and number of the holes 11e correspond to the positions and number of the holes 91e of the pressure relief device mounting portion 91d.

[0020] FIG. 4B is a front view showing another example of the pressure release plate according to the first embodiment. In the example shown in FIG. 4B, the U-shaped slit 11a is not formed. The pressure release plate 111 extends in the y-axis direction, and the elastically deformable deformation portion 111b is provided in the center in the z-axis direction. The deformation portion 111b is formed across both ends of the pressure release plate 111 in the y-axis direction, and the upper portion above the deformation portion 111b is the fixed portion 111d, and the lower portion below the deformation portion 111b is the movable portion 111c. The movable portion 111c rotates around the y-axis around the deformation portion 111b as a result of the elastic deformation of the deformation portion 111b. As a result, the movable portion 111c performs a hinge-like opening and closing motion, and the movable portion 111c is movable between a closed position and an open position. The fixed portion 111d is formed with a hole 11e into which the bolt 81 is inserted, and is fixed to the pressure release device mounting portion 91d by the bolt 81 and a nut 82.

[0021] 4C is a front view showing another example of the pressure release plate according to the first embodiment. The pressure release plate 112 has two linear slits 11f1 and 11f2 extending from the center of the pressure release plate 112 in the z-axis direction to the lower end at the opposing portions, and the deformation portion 112b extends in the y-axis direction between the linear slits 11f1 and 11f2 at the center of the pressure release plate 112 in the z-axis direction. In the pressure release plate 112, a movable portion 112c is formed between the linear slits 11f1 and 11f2, and a fixed portion 112d is formed in the other portion, that is, above the deformation portion 112b and below the deformation portion 112b but at the end side in the y-axis direction from the linear slits 11f1 and 11f2. The movable portion 112c opens and closes like a hinge, and the movable portion 112c is movable between a closed position and an open position. The fixing portion 112d has a hole 11e into which a bolt 81 is inserted, and is fixed to the pressure relief device mounting portion 91d by the bolt 81 and a nut 82. The straight slit 11f1 and the straight slit 11f2 correspond to a first slit portion and a second slit portion, respectively. In this manner, the pressure relief plate may be configured to have two slits at positions facing each other, and the area sandwiched between these two slits becomes the movable portion.

[0022] FIG. 5 is a perspective view for explaining a fixing method of the torsion coil spring according to the first embodiment. The coordinate axes shown in FIG. 5 indicate the directions in a state in which the pressure release device 10 is attached to the storage box 91. The support 13 is configured by bending two plate-like members into an L-shape, and is fixed to both sides of the movable part 11c of the pressure release plate 11 in the y-axis direction. The support 13 includes a side part 13a perpendicular to the y-axis direction and provided with a through hole 13aa through which the shaft 14 passes, a bottom part 13b perpendicular to the side part 13a (perpendicular to the x-axis direction) and provided with a hole (not shown) through which the bolt 81 is inserted, and a rising part 13c in which a part of the inner side (the side close to the movable part 11c) of the bottom part 13b is raised in the -x-axis direction, i.e., toward the shaft 14. A gap is provided between the rising part 13c and the shaft 14. The width of this gap is configured to be smaller than the thickness of the winding constituting the winding part 15a of the torsion coil spring 15. Furthermore, a hole 13ca is provided in the rising portion 13c. Through holes 13aa provided in the side portions 13a of the supports 13 on both sides face each other. The shaft 14 extends along the y-axis direction and is supported by the supports 13 on both sides by penetrating the through holes 13aa on both sides. Note that the support 13 is not limited to being plate-shaped as long as it is configured to support the shaft 14 on both sides of the movable portion 11c in the y-axis direction. For example, the support 13 may be a box body provided with a hole through which the shaft 14 passes and fixed to the pressure relief device mounting portion 91d.

[0023] The torsion coil spring 15 has a double torsion shape as described above, and is fixed to the shaft 14 by the shaft 14 penetrating through the two winding parts 15a. The winding part 15a is disposed inside the rising part 13c, that is, between the movable part 11c and the rising part 13c. As described above, the width of the gap between the rising part 13c and the shaft 14 is smaller than the thickness of the winding constituting the winding part 15a, so that the movement of the winding part 15a along the axial direction of the shaft 14 is restricted by the rising part 13c. In addition, one end of the winding part 15a extends in the -z axis direction (downward), and the winding parts 15a on both sides form a U-shaped pressing part 15b. In other words, the pressing part 15b formed in a U-shape is connected to one end of each of the two winding parts. The pressing part 15b is the point of action of the torsion coil spring 15. The other end 15c of the winding portion 15a passes through a hole 13ca of the rising portion 13c and engages with the hole 13ca. As a result, the end 15c serves as a fixed end of the torsion coil spring 15.

[0024] Fig. 6 is an AA cross-sectional view of the pressure release device in the first embodiment, showing the state where the pressure release plate is in the sealed position. As shown in Fig. 6, when the pressure release plate 11 is in the sealed position, the deformation portion 11b is not deformed, and the entire pressure release plate 11 is in a flat plate shape extending in the vertical direction. The movable portion 11c is in close contact with the pressure release device mounting portion 91d, and blocks the pressure release hole 91c and the opening 12c of the cover 12. The pressing portion 15b applies a load F to the movable portion 11c by the elastic force of the torsion coil spring 15 so as to press the movable portion 11c against the pressure release device mounting portion 91d, thereby holding the movable portion 11c in the sealed position.

[0025] In addition, the side wall of the cover 12 on the +x-axis direction side (storage box 91 side) is fixed to the pressure relief device mounting part 91d without any gaps other than the opening 12c and is in close contact with the pressure relief device mounting part 91d. An opening 12b is provided on the lower side, and the lower end part 12d on the +x-axis direction side of the cover 12 is also in close contact with the pressure relief device mounting part 91d. Therefore, the cover 12 seamlessly covers the outer periphery of the movable part 11c in the sealed position. Any foreign matter that has entered the cover 12 from the opening 12b is prevented from entering the storage box 91 by the movable part 11c in the sealed position. Therefore, the cover 12 having the above-mentioned structure can prevent foreign matter from entering the storage box 91 not only from the horizontal direction (x-axis direction and y-axis direction) and the upper direction but also from the lower direction.

[0026] The pressure release operation by the pressure release device 10 will be described. FIG. 7 is a cross-sectional view of the pressure release device in the first embodiment, showing a state in which the pressure release plate is in an open position. When the switch 100 stored in the storage box 91 performs a current interruption operation, the pressure inside the storage box 91 increases. As shown in FIG. 7, the increased pressure increases the load P on the movable part 11c of the pressure release plate 11 in a direction toward the outside of the storage box 91. As described above, the load F is applied to the movable part 11c mainly by the torsion coil spring 15. When the pressure inside the storage box 91 increases and exceeds the first pressure, the load P exceeds the load F, the deformation part 11b begins to elastically deform, and the movable part 11c moves away from the pressure release device mounting part 91d. The movable part 11c is pushed by the load P and rotates around the y-axis with the deformation part 11b as the center. The direction of rotation is the direction in which the movable part 11c is lifted (clockwise in FIG. 7). Movable part 11c rotates until its lower end abuts against the inner wall of cover 12, and reaches the open position shown in FIG. 7. The rotation of movable part 11c described above also rotates pressing part 15b of torsion coil spring 15. When movable part 11c reaches the open position, the lower end of pressing part 15b and the lower end of end part 15c also abut against the inner surface of cover 12. The "first pressure" is determined in advance by the mass of movable part 11c and the elastic force of torsion coil spring 15.

[0027] When the movable part 11c moves away from the pressure release device mounting part 91d and the blockage of the pressure release hole 91c is released, the gas G in the storage box 91 starts to be released to the outside of the storage box 91 through the pressure release hole 91c and the opening 12c. Pressure is released by releasing the gas G to the outside of the storage box 91 in this manner. The gas G released to the outside of the storage box 91 flows into the cover 12, but because the cover 12 covers the pressure release hole 91c without any gaps, the gas G is released to the outside of the cover 12 only through the opening 12b.

[0028] When the movable part 11c is in the open position, the movable part 11c is subjected to a load P, a reaction force N (not shown) from the inner surface of the cover 12, a load F from the torsion coil spring 15, a load FK (omitted in FIG. 7) due to the elastic force of the deformable part 11b, and gravity FG (omitted in FIG. 7). The load P acts to hold the movable part 11c in the open position, and the reaction force N prevents the movable part 11c from further rotating. The load F acts to return the movable part 11c to the sealed position as shown in FIG. 7. In addition, since the deformable part 11b tries to return to its original shape, the load FK also acts to return the movable part 11c to the sealed position. In addition, the gravity FG also acts to return the movable part 11c to the sealed position. When the pressure inside the storage box 91 decreases below the second pressure due to pressure release, the force holding the movable part 11c in the open position by the load P falls below the force returning the movable part 11c to the sealed position by the load F, the load FK, and gravity FG, and the movable part 11c starts a return operation to return to the sealed position, and finally returns to the sealed position. After returning to the sealed position, the movable part 11c is pressed against the pressure release device mounting part 91d by the pressing part 15b, closing the pressure release hole 91c. The "second pressure" is determined in advance by the mass of the movable part 11c, the elastic force of the deformation part 11b, and the elastic force of the torsion coil spring 15.

[0029] The return operation of the pressure release plate 11 will be further described. FIG. 8 is a diagram for explaining the return operation of the pressure release plate. For comparison, FIG. 8 shows the pressure release plate 11 in the sealed position on the left side, and the pressure release plate 11 in the open position on the right side. First, gravity FG acts on the center of gravity 11g of the movable part 11c. When the movable part 11c is in the open position, the movable part 11c is inclined with respect to the direction of gravity FG, so that gravity FG has a component in a direction perpendicular to the side of the movable part 11c. Also, when comparing the open position state and the sealed position state, the center of gravity 11g in the open position is in a higher position than the center of gravity 11g in the sealed position, so that the open position has a larger potential energy for gravity. Therefore, gravity FG acts to rotate the movable part 11c in a direction returning to the sealed position (counterclockwise around the y-axis in FIG. 8) so that the movable part 11c returns from the open position to the sealed position and the center of gravity 11g returns to the sealed position state.

[0030] Next, regarding the elastic force of the deformation part 11b, in the closed position, the deformation part 11b is not deformed, and no elastic force is generated. On the other hand, in the open position, the deformation part is elastically deformed such that the +x side of the deformation part expands and the -x side contracts, and an elastic force FE is generated in the deformation part 11b to cancel this elastic deformation. Due to the elastic force FE, a load FK acts on the movable part 11c in the open position in the direction returning it to the closed position.

[0031] Furthermore, as described above, the load F also acts on the movable part 11c from the torsion coil spring 15 (omitted in FIG. 8) in a direction returning the movable part 11c to the sealed position. As described above, the pressure release device 10 is configured so that the movable part 11c of the pressure release plate 11 automatically returns from the open position to the sealed position by utilizing the load F, gravity FG, and load FK.

[0032] The pressure release plate 11 is made of a thin plate made of an elastically deformable resin material. For example, the pressure release plate 11 may be made of insulating paper containing aramid polymer fibers. There is no limit to the thickness of the pressure release plate 11, but the thinner the pressure release plate 11 is made, the lighter it becomes. This reduces the load generated on the pressure release plate 11 by the shock and vibration caused by the operation of the switch 100, so that the load (closing load) for holding the pressure release plate 11 in the closed position can be reduced. When the closing load is smaller, a smaller torsion coil spring 15 can be used, and the pressure release device 10 can be made smaller and lighter. In addition, when the pressure release plate 11 is made thinner, the elastic force of the deformation portion 11b and the gravity acting on the movable portion 11c are also reduced. As described above, the elastic force of the deformation portion 11b and the gravity acting on the movable portion 11c act to move the movable portion 11c to the closed position, so when these forces are small, it is easier to move the movable portion 11c to the open position during pressure release. Therefore, when the switch 100 performs a current interruption operation and the pressure inside the storage box 91 rises, the movable part 11c moves to the open position in a shorter time, thereby making it possible to further suppress the pressure rise inside the storage box 91. In this case, the required strength of the storage box 91 can be further reduced, and the structure of the storage box 91 can be further simplified and the weight of the storage box 91 can be further reduced.

[0033] Conversely, if the thickness of the pressure release plate 11 is increased, the above-mentioned effects such as weight reduction are not as great as those obtained when the pressure release plate 11 is made thinner, but the strength of the pressure release plate 11 can be increased.

[0034] According to the first embodiment, it is possible to reduce the weight of the storage box while preventing the intrusion of foreign matter into the storage box. That is, the movable part of the pressure release plate in the first embodiment is configured to return from the open position to the sealed position using only the elastic force of the pressure release plate itself, the elastic force of the torsion coil spring, and gravity, and the movable part of the pressure release plate can be realized to be simple and lightweight. Since pressure is released faster when the pressure release hole is more widely open, the faster the movable part moves from the sealed position to the open position, the faster the pressure is released. By reducing the weight of the movable part as described above, when the effect of gravity is taken into account, the movable part DepartmentThe lighter the pressure relief plate is, the shorter the time it takes to move from the closed position to the open position, and the quicker the pressure relief can be achieved, thereby more effectively suppressing the pressure rise inside the storage box. If the pressure rise inside the storage box can be more effectively suppressed, the strength required for the storage box is smaller. This allows the structure of the storage box to be simplified and the weight of the storage box to be reduced. In addition, the upper and sides of the pressure relief plate are covered, which prevents foreign objects from entering the storage box.

[0035] It is generally known that if the pressure inside the storage box rises when current is interrupted, the arc in the arc-extinguishing chamber inside the switchgear 100 becomes more likely to restrike. When restrike of the arc occurs, the arc voltage generated by the switchgear 100 decreases, which causes a problem of longer current interruption time, but the pressure relief device in the first embodiment also has the effect of reducing the pressure rise inside the storage box, which makes it possible to prevent restrike of the arc and shorten the current interruption time.

[0036] Furthermore, since the handle portion is integrally provided on the top of the cover, there is no need to provide a separate handle to hold the storage box when transporting it, which reduces the number of parts.

[0037] In addition, the winding section is sandwiched between the raised portion provided on the support and the movable portion of the pressure release plate, and the width of the gap between the raised portion and the shaft is smaller than the thickness of the wire that constitutes the winding section, so that the movement of the winding section along the axial direction of the shaft is restricted by the raised portion. This ensures that the position of the torsion coil spring is fixed without shifting along the axial direction of the shaft, even if vibrations and shocks occur due to the sealing and opening operations of the pressure release device. This makes it possible to suppress variations in the load applied to the pressure release plate.

[0038] In addition, because the cover completely covers the pressure relief hole, gas released to the outside of the storage box 91 during pressure relief is released downward from the cover only through the opening at the bottom end of the cover. Therefore, materials released together with the gas from inside the storage box are released only downward, preventing the materials from scattering over a wide area and suppressing adverse effects of the materials on surrounding equipment.

[0039] In addition, in the open position, the lower end of the movable part of the pressure relief plate and the lower ends of the fixed end and pressing part of the torsion coil spring abut against the inner surface of the cover, so that the reaction force from the inner surface of the cover limits the amount of movement of the movable part and the torsion coil spring, preventing damage to the pressure relief plate and the torsion coil spring.

[0040] Embodiment 2 Next, a second embodiment will be described with reference to Figs. 9 and 10. The same or corresponding parts as those in Figs. 1 to 8 are denoted by the same reference numerals, and their description will be omitted. Fig. 9 is a cross-sectional view of the pressure release device in the second embodiment taken along line AA, showing a state in which the pressure release plate is in a sealed position. Fig. 10 is a view showing a state in which the pressure release plate is in an open position. The pressure release device 20 is obtained by replacing the pressure release plate 11 of the pressure release device 10 in the first embodiment with a pressure release plate 21 shown in Figs. 9 and 10. The pressure release plate 21 has a plate-shaped portion and an arm (described later), and is made of a material that is difficult to deform elastically. For this reason, the pressure release plate 21 does not have a portion that deforms elastically like the deformation portion 11b of the pressure release plate 11, and the entire plate-shaped portion of the pressure release plate 21 is a movable portion 21c. The pressure relief plate 21 is made of, for example, an iron-based metal such as iron or stainless steel, a non-ferrous metal such as aluminum or copper, or an insulating material (thermoplastic resin or thermosetting resin) such as epoxy resin or polyethylene resin, and has greater rigidity than the pressure relief plate 11. Note that the thickness of the pressure relief plate 21 is not particularly limited, but from the viewpoint of weight reduction, it is preferable to configure it as thin as possible.

[0041] The pressure relief plate 21 has an arm 27 at the upper end of the movable part 21c. The arm 27 is made of, for example, metal, and is configured to rise from the movable part 21c. When the movable part 21c is in the sealed position as shown in FIG. 9, the arm 27 extends from the movable part 21c in the -x-axis direction. The arm 27 has a hole 27a into which the shaft 14 fits, and the arm 27 and the movable part 21c are fixed to the shaft 14 that fits into the hole 27a. With this configuration, the movable part 21c can rotate together with the shaft 14. The torsion coil spring 15 is attached to the shaft 14, and the movable part 21c is held in the sealed position by the load of the torsion coil spring 15, as in the first embodiment. Also, the movable part 21c moves from the sealed position to the open position due to the pressure rise in the storage box 91 when the current is interrupted, as in the first embodiment. Also, although there is no effect of elastic deformation and elastic force as in the pressure relief plate 11 of embodiment 1, the pressure relief plate 21 returns to the sealed position after pressure relief, similar to embodiment 1. When the load F and gravity FG (omitted in Figs. 9 and 10) due to the torsion coil spring 15 exceed the load P (omitted in Figs. 9 and 10) due to the pressure inside the storage box 91, the load F and gravity FG cause the pressure relief plate 21, which is in the open position, to return to the sealed position.

[0042] The corner of the movable part 21c facing the upper storage box 91 is cut, forming a cut part 21f with the edge removed. When the movable part 21c moves from the sealed position to the open position, the side facing the upper storage box 91 is pressed against the pressure relief device mounting part 91d. At this time, if there is an edge, the edge and the -x side surface of the pressure relief device mounting part 91d may interfere with each other, and smooth movement from the sealed position to the open position may be hindered. However, by forming the cut part 21f, the cut part 21f moves so as to slide on the -x side surface of the pressure relief device mounting part 91d. Therefore, smooth movement of the movable part 21c from the sealed position to the open position is not hindered. The rest is the same as in the first embodiment, so the description will be omitted.

[0043] According to the second embodiment, the pressure release plate is made of a metal material or a resin material that has a higher rigidity and is hardly elastically deformed, which makes it possible to further improve the flame retardancy and strength of the pressure release plate.

[0044] Embodiment 3 Next, the third embodiment will be described with reference to FIG. 11. The same or corresponding parts as those in FIG. 1 to FIG. 10 are denoted by the same reference numerals, and the description thereof will be omitted. FIG. 11 is a cross-sectional view of the pressure release device in the third embodiment taken along line AA, showing a state in which the pressure release plate is in a sealed position. The pressure release device 30 is obtained by omitting the torsion coil spring 15 from the pressure release device 10 in the first embodiment. In addition, with the omission of the torsion coil spring 15, the shaft 14 and the support 13 are also omitted. As described above, since the deformation portion 11b has elasticity, a certain degree of sealing can be obtained with the pressure release plate 11 alone. That is, when the movable portion 11c is in the sealed position, the elastic force of the deformation portion 11b applies a load to the movable portion 11c in a direction to hold it in the sealed position. Also, as can be seen from FIG. 8, when the movable portion 11c is in the open position, the elastic force of the deformation portion 11b applies a load to the movable portion 11c in a direction to return to the sealed position. That is, even without the load F of torsion coil spring 15, the return operation from the open position to the closed position is realized by the load due to the elastic force of deformation portion 11b and gravity FG. The rest is the same as in the first embodiment, so the description will be omitted.

[0045] According to the third embodiment, the torsion coil spring, the shaft, and the support are omitted, and therefore the configuration of the pressure release device can be further simplified and the weight of the pressure release device can be further reduced.

[0046] Embodiment 4 Next, a fourth embodiment will be described with reference to FIG. 11 The same or corresponding parts are denoted by the same reference numerals and their explanation will be omitted. Fig. 12 is a front view of a pressure release device in embodiment 4. A pressure release device 40 is configured by removing the handle portion 12a from the cover 12 in embodiment 1 and using this as a cover 42. The rest is the same as in the first embodiment, so the description will be omitted.

[0047] According to the fourth embodiment, the handle is omitted from the cover, so the cover is made smaller, and therefore the pressure relief device can be made smaller and lighter.

[0048] Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless modifications not exemplified are assumed within the scope of the technology disclosed in this application, including, for example, modifying, adding, or omitting at least one component, and further, extracting at least one component and combining it with a component of another embodiment. [Explanation of symbols]

[0049] 10, 10A, 10B, 20, 30, 40 Pressure relief device, 11, 111, 112, 21 Pressure relief plate, 11a U-shaped slit, 11b, 111b, 112b Deformation portion, 11c, 111c, 112c, 21c Movable portion, 11d, 111d, 112d Fixed portion, 11f1, 11f2 Straight slit, 12, 42 Cover, 12a Handle portion, 12b, 12c Opening, 12d Lower end, 13 Support, 13a Side portion, 13aa Through hole, 13b Bottom portion, 13c Raised portion, 14 Shaft, 15 Torsion coil spring, 15a Winding portion, 15b Holding portion, 15c End portion, 21f Cut portion, 27 Arm, 91 Storage box, 91Aa, 91Ab Side wall, 91c pressure relief hole, 91d pressure relief device mounting part, 100 switch, 1000 switch device, F load, FG gravity, FE elastic force, FK load, P load

Claims

1. A storage box for storing a switch, the storage box having a pressure relief hole for relieving internal pressure provided in a side wall, and a pressure relief device for the switch attached to the side wall, The pressure relief device of the switch comprises: a pressure release plate having a movable part that is movable between a sealing position that seals the pressure release hole and an opening position that opens the pressure release hole, and a deformation part that is elastically deformable and deforms in accordance with the movement of the movable part, the movable portion and the deformable portion of the pressure release plate are made of an elastically deformable resin material, The elastic force of the deformation portion applies a load to the movable portion in a direction returning to the closed position when the movable portion is in the open position, The storage box is characterized in that the movable portion automatically returns from the open position to the closed position where no elastic force is generated in the deformable portion.

2. A storage box as described in claim 1, wherein the pressure relief plate has a first slit portion and a second slit portion opposed to each other, and the movable portion is formed in the area sandwiched between the first slit portion and the second slit portion.

3. 2. The storage box according to claim 1, wherein the pressure relief plate is provided with a U-shaped slit, and the movable portion is provided within an area surrounded by the U-shaped slit.

4. 4. A storage box as described in any one of claims 1 to 3, further comprising a torsion coil spring that applies a load to the movable part in a direction to maintain the movable part in the sealed position when the movable part is in the sealed position, and applies a load to the movable part in a direction to return to the sealed position when the movable part is in the open position.

5. The movable part is a movable part that rotates around one end as a central axis, The device further includes a support fixed to the side wall on both sides in the direction of the central axis, and a shaft supported by the support through a through hole provided in the support, 5. The storage box according to claim 4, wherein the torsion coil spring is fixed to the shaft.

6. A storage box for storing a switch, the storage box having a pressure relief hole for relieving internal pressure provided in a side wall, and a pressure relief device for the switch attached to the side wall, The pressure relief device of the switch comprises: a pressure relief plate having a movable part which rotates about one end as a central axis and can move between a sealing position which seals the pressure relief hole and an opening position which opens the pressure relief hole, the corner of the upper end of which on the side wall side is cut off; Support bodies fixed to the side walls on both sides in the direction of the central axis; a shaft that passes through a through hole provided in the support and is supported by the support; a torsion coil spring fixed to the shaft, the torsion coil spring applying a load to the movable part in a direction to hold the movable part in the sealed position when the movable part is in the sealed position, and applying a load to the movable part in a direction to return to the sealed position when the movable part is in the open position, The pressure relief plate has a flat plate-shaped portion and an arm provided at one end of the plate-shaped portion and having a hole into which the shaft fits, and the entire plate rotates together with the shaft.

7. 7. The storage box according to claim 5, wherein the torsion coil spring comprises two winding portions through which the shaft passes, and a pressing portion formed in a U-shape and connected to one end of each of the two winding portions, and which applies a load to the movable portion.

8. 8. The storage box of claim 7, wherein the support body has two plate-like members each bent into an L-shape, and each of the two plate-like members has a side portion perpendicular to the central axis and in which the through hole is provided, a bottom portion perpendicular to the side portion, and a raised portion formed by raising a portion of the bottom portion closer to the movable portion toward the shaft, and the raised portion sandwiches the winding portion between the movable portion and the winding portion in the direction of the central axis, and a gap having a width smaller than the thickness of the winding that constitutes the winding portion is provided between the raised portion and the shaft.

9. 9. The storage box according to claim 1, further comprising a cover covering the upper and side surfaces of the pressure relief plate and having an opening at a lower end thereof.

10. A cover is further provided to cover the upper and side portions of the pressure relief plate and to have an opening at a lower end thereof. The storage box according to claim 7 or 8, wherein the pressing portion abuts against an inner surface of the cover when the movable portion is in the open position.

11. 11. The storage box according to claim 9 or 10, wherein a grippable handle is integrally provided on an upper portion of the cover.

12. A storage box as described in any one of claims 1 to 11, wherein the movable part is normally maintained in the sealed position, and when the pressure rises due to a current interruption operation of the switch and exceeds a predetermined first pressure, the movable part moves to the open position to release the pressure inside the storage box, and when the pressure falls below a predetermined second pressure, the movable part returns to the sealed position.

13. A switchgear comprising: the storage box according to claim 1 ; and a switch accommodated in the storage box.

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