Operation mechanism for circuit breaker and switchgear

Abstract

To provide a cost-reduced, compact and reliability-improved operation mechanism capable of smoothly performing an opening / closing operation on a pair of electrodes of a circuit breaker using a single (one) screw shaft.SOLUTION: An operation mechanism comprises: one screw shaft 8 extending in parallel in an opening / / closing direction D1 of a movable electrode 6; a nut part 9 which is movable along the screw shaft; a guide shaft 10 which extends in parallel with the screw shaft; a bearing part 11 which is movable along the guide shaft; an operation rod 12 in which the movable electrode is connected to one end; and a connection plate 13 to which the other end of the operation rod is connected. The connection plate consists of: a center region 13a equally bisecting the connection plate; and side regions 13b and 13c at both sides of the center region, in a view in a direction D2 which is orthogonal to the opening / closing direction. The nut part and the bearing part are fixed to the connection plate in such a manner that the screw shaft is positioned in the center region and any one of the side regions and that the guide shaft is positioned in the side regions.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to an operating mechanism and a switch gear of a switch.

Background Art

[0002] As a switching device for power reception and distribution provided in buildings and large facilities, for example, a switch gear including a switch such as a circuit breaker or a disconnector is known. In the switch gear, as components of the switch, a pair of electrodes and an operating mechanism thereof are applied. In this case, by opening and closing the pair of electrodes by the operating mechanism, interruption of fault current and opening and closing of load current are performed, and power is stably supplied from the switch gear.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional operating mechanism, a pair of electrodes are relatively opened and closed by rotating a plurality of screw shafts simultaneously. For this reason, the conventional operating mechanism is equipped with, for example, a connecting gear structure for connecting the screw shafts so as to rotate the plurality of screw shafts simultaneously, or a support structure for rotatably supporting each screw shaft so that the plurality of screw shafts are arranged parallel to each other.

[0005] However, when a connecting gear structure, a support structure, etc. are mounted, not only does the number of parts increase accordingly, resulting in an increase in the manufacturing cost of the operating mechanism, but also due to the need to secure accommodation space corresponding to the increased number of parts, there are certain restrictions on the compactification of the operating mechanism.

[0006] Furthermore, in order to smoothly open and close a pair of electrodes by a plurality of screw shafts, it is required to always maintain the screw shafts in a parallel positional relationship with each other. However, it is difficult to maintain such a positional relationship over a long period of time, and it cannot be denied that a highly reliable operation mechanism cannot be realized in this case.

[0007] As a measure to solve such problems, it is possible to assume a technique of opening and closing a pair of electrodes by a single (one) screw shaft. However, at present, a technique that enables a highly reliable opening and closing operation with only a single (one) screw shaft is not known.

[0008] An object of the present invention is to realize a low-cost, compact, and highly reliable operation mechanism capable of smoothly opening and closing a pair of electrodes of a switch by a single (one) screw shaft.

Means for Solving the Problems

[0009] According to one embodiment, there are provided one screw shaft extending parallel along the opening and closing direction of a movable electrode, a nut portion movable along the screw shaft, a guide shaft extending parallel to the screw shaft, a bearing portion movable along the guide shaft, an operation rod having a movable electrode connected to one end thereof, and a connecting plate to which the other end of the operation rod is connected. The connecting plate includes a center region that bisects the connecting plate and side regions on both sides of the center region when viewed in a direction orthogonal to the opening and closing direction. The nut portion and the bearing portion are fixed to the connecting plate such that the screw shaft is positioned in either the center region or the side region, and the guide shaft is positioned in the side region.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0011] "One Embodiment" FIG. 1 is a perspective configuration diagram of an operating mechanism 1 of a switchgear according to the present embodiment and a switchgear including the operating mechanism 1, FIG. 2 is a plan configuration diagram thereof, and FIG. 3 is a cross-sectional configuration diagram thereof. As shown in FIGS. 1 to 3, among the components of the switchgear, a three-phase electrode unit (R-phase electrode unit Re, S-phase electrode unit Se, T-phase electrode unit Te) is shown as an example, and among the components of the switchgear, an operating mechanism 1 for opening and closing (also referred to as making and breaking operation) the three-phase electrode units Re, Se, Te is shown.

[0012] As shown in FIGS. 1 to 3, the inside of the switchgear is partitioned into two by a partition wall 2. On one side of the partition wall 2, a main circuit structure 3 (for example, the three-phase electrode units Re, Se, Te described later) through which current flows during power reception and distribution is housed. On the other side of the partition wall 2, an operating structure 4 (for example, the operating mechanism 1 described later) for controlling the flow of current by operating the main circuit structure 3 is housed.

[0013] First, the main circuit structure 3 includes a pair of electrodes (fixed electrode 5, movable electrode 6) that constitute the three-phase electrode units Re, Se, Te. Among these three-phase electrode units Re, Se, Te, the pair of electrodes (fixed electrode 5, movable electrode 6) have the same arrangement configuration with respect to each other. The fixed electrode 5 is fixed to a preset part of the main circuit structure 3. The movable electrode 6 is configured to be movable in a preset opening and closing direction (also referred to as a making and breaking direction) D1 by an operating mechanism 1 described later, and is disposed opposite to the fixed electrode 5 so as to be openable and closable.

[0014] In FIGS. 1 to 3, as an example of the three-phase electrode units Re, Se, and Te, a plurality (i.e., three) of fixed electrodes 5 and the same number (i.e., three) of movable electrodes 6 as the fixed electrodes 5 are applied. The three fixed electrodes 5 are arranged at intervals along a direction D2 orthogonal to the opening / closing direction D1. Similarly, the three movable electrodes 6 are arranged at intervals along a direction D2 orthogonal to the opening / closing direction D1.

[0015] In this case, the three fixed electrodes 5 are arranged at equal intervals along the direction D2 orthogonal to the opening / closing direction D1. The three movable electrodes 6 are arranged at equal intervals along the direction D2 orthogonal to the opening / closing direction D1. That is, the intervals between the fixed electrodes 5 and the intervals between the movable electrodes 6 are set to be the same (equal) to each other. And the opening / closing timing and the opening / closing stroke of the movable electrode 6 with respect to the fixed electrode 5 are set to be the same (equal) among the three-phase electrode units Re, Se, and Te.

[0016] Thereby, when the three-phase electrode units Re, Se, and Te are opened / closed by the operation mechanism 1 described later, it becomes possible to simultaneously bring the three movable electrodes 6 into contact with the three fixed electrodes 5 one by one or to simultaneously separate them.

[0017] Next, the operation structure includes an operation mechanism 1. The operation mechanism 1 is constructed on a base plate 7 fixed to the partition wall 2. The operation mechanism has one (also referred to as one) screw shaft 8, a nut portion 9, a guide shaft 10, a bearing portion 11, an operation rod 12, and a connecting plate 13.

[0018] In the example of FIGS. 1 to 3, the operation mechanism 1 is laid out around one screw shaft 8. The screw shaft 8 extends parallel to the opening / closing direction D1 of the movable electrode 6, and a spiral cut (for example, a male screw groove not shown) is formed on the surface. The screw shaft 8 is rotatably supported by a pair of support plates 14 provided on the base plate 7.

[0019] A pair of support plates 14 are constructed by rising from the base plate 7, and are arranged to face each other in parallel along the opening and closing direction D1. Both sides of the screw shaft 8 are rotatably supported by a pair of support plates 14. In this case, in order to maintain the rotational property of the screw shaft 8 constantly, it is preferable to interpose an existing lubricant (for example, bearing 15) between the screw shaft 8 and the support plate 14.

[0020] A nut portion 9 is screwed onto the screw shaft 8. A spiral groove (for example, an internal thread groove not shown) is formed on the inner circumference of the nut portion 9, and this internal thread groove is screwed onto the male thread groove of the screw shaft 8. Thereby, the nut portion 9 is configured to be movable (i.e., reciprocating) along the screw shaft 8 by rotating the screw shaft 8. Needless to say, as the types of these screw grooves, existing screws such as trapezoidal screws and triangular screws can be applied.

[0021] The screw shaft 8 is provided between two (also referred to as two) guide shafts 10. Both guide shafts 10 extend parallel to the screw shaft 8. Both guide shafts 10 are arranged on a virtual circle (not shown) centered on the screw shaft 8. In other words, when viewed in the radial direction of the virtual circle, both guide shafts 10 are arranged at an equal linear distance from the screw shaft 8. That is, the linear distance between one guide shaft 10 and the screw shaft 8 is set to be the same as the linear distance between the other guide shaft 10 and the screw shaft 8.

[0022] The guide shaft 10 is configured to have a constant (uniform) thickness over its entire length. As the cross-sectional shape of the guide shaft 10, various shapes such as circular, elliptical, triangular, and rectangular can be applied. For example, assuming a guide shaft 10 with a circular cross-section (i.e., cylindrical), the guide shaft 10 is configured to have a constant (uniform) diameter over its entire length.

[0023] The guide shafts 10 of both sides are inserted into the bearing parts 11 one by one. These two bearing parts 11 have a hollow shape through which the guide shaft 10 can be inserted. The bearing part 11 into which the guide shaft 10 is inserted is configured to be movable along the guide shaft 10. In this case, it is preferable that the bearing part 11 is configured to be smoothly movable along the guide shaft 10 without play.

[0024] For example, assuming a guide shaft 10 with a circular cross-section (i.e., cylindrical), it is preferable that the inner surface shape of the hollow part of the bearing part 11 is also circular in cross-section (i.e., hollow cylindrical). More preferably, the diameter of the surface of the cylindrical guide shaft 10 and the diameter of the inner surface of the bearing part 11 may be set equal to each other, or the diameter of the inner surface of the bearing part 11 may be set slightly larger than the diameter of the surface of the guide shaft 10.

[0025] Here, the surface of the guide shaft 10 and the inner surface of the bearing part 11 are preferably both configured as smooth surfaces without irregularities. When the diameter of the surface of the guide shaft 10 and the diameter of the inner surface of the bearing part 11 are set equal to each other, it is preferable to interpose a component (e.g., lubricant, lubricating oil) that maintains lubricity between the surface and the inner surface. In addition, as the inner surface structure of the bearing part 11, for example, a ball bearing structure in which a plurality of balls are circulated so as to be rollable may be applied.

[0026] Furthermore, a plurality of operating rods 12 are provided in parallel with the above-described screw shaft 8 and guide shaft 10 (i.e., parallel along the opening / closing direction D1). In the examples of FIGS. 1 to 3, the same number (i.e., three) of operating rods 12 as the above-described three movable electrodes 6 are provided. The three (also referred to as three) operating rods 12 are arranged parallel to each other. These operating rods 12 each form a straight bar shape and are set to have the same overall length. Each operating rod 12 extends through the partition wall 2, and the extended end (i.e., one end) thereof is connected to one of the above-described three movable electrodes 6 one by one.

[0027] As described above, the three movable electrodes 6 are arranged at equal intervals along the direction D2 orthogonal to the opening / closing direction D1. Therefore, the three operation rods 12 connected to these movable electrodes 6 are also arranged at equal intervals along the direction D2 orthogonal to the opening / closing direction D1, with the same interval as the interval between the movable electrodes 6.

[0028] Such an operation rod 12 is configured to be movable (slidable) via the partition wall 2. At this time, it is preferable to move (slide) the three operation rods 12 at the same timing and with the same stroke. For this reason, a connecting plate 13 described later is provided.

[0029] The connecting plate 13 extends in the direction D2 orthogonal to the opening / closing direction D1. In FIGS. 1 to 3, as an example, a plate-shaped connecting plate 13 having a rectangular contour is shown. In this case, when viewed in the direction D2 orthogonal to the opening / closing direction D1, the other ends of the above-described operation rods 12 (that is, the extending ends on the opposite side of the one end connected to the movable electrode 6) are connected to the rectangular connecting plate 13 at equal intervals.

[0030] The connecting plate 13 is composed of a center region 13a that bisects the connecting plate 13 and side regions 13b and 13c on both sides of the center region 13a when viewed in the direction D2 orthogonal to the opening / closing direction D1. Thereby, the three operation rods 12 are positioned in a state where their other ends are respectively connected to the center region 13a and the both side regions 13b and 13c one by one.

[0031] In such a connecting plate 13, the above-described nut portion 9 is fixed to the center region 13a, and further, the above-described two bearing portions 11 are respectively fixed to the both side regions 13b and 13c one by one. In the example of FIGS. 1 to 3, the nut portion 9 is positioned directly below the operation rod 12 positioned in the center region 13a when viewed in the direction D3 orthogonal to both the opening / closing direction D1 and the direction D2 orthogonal to the opening / closing direction D1.

[0032] In this state, the screw shaft 8 with the nut portion 9 screwed thereon is positioned in the center region 13a. The two guide shafts 10 inserted through the two bearing portions 11 are respectively positioned, one each, in both side regions 13b and 13c. As a result, in the center region 13a, the screw shaft 8 is positioned directly below the operation rod 12. In both side regions 13b and 13c, the guide shaft 10 is positioned between two adjacent operation rods 12.

[0033] Next, an example of the operation of the operation mechanism 1 will be described. That is, the screw shaft 8 is rotated manually or electrically (by a motor). As the screw shaft 8 rotates, the nut portion 9 moves along the screw shaft 8. The movement of the nut portion 9 is transmitted to the connecting plate 13, moving the connecting plate 13. At this time, as the connecting plate 13 moves, the bearing portion 11 moves along the guide shaft 10. As a result, the connecting plate 13 moves together with the nut portion 9 while maintaining a certain posture. The movement of the connecting plate 13 is transmitted to the three operation rods 12, moving these operation rods 12 simultaneously. At this time, as each operation rod 12 moves, the three movable electrodes 6 connected to the operation rod 12 move. Thereby, the three movable electrodes 6 can be simultaneously brought into contact with or separated from the three fixed electrodes 5 one by one.

[0034] As described above, according to the present embodiment, with only one screw shaft 8, a plurality of movable electrodes 6 can be simultaneously opened and closed with respect to a plurality of fixed electrodes 5. In this case, a support structure for supporting a plurality of screw shafts and a connecting gear structure for simultaneously rotating a plurality of screw shafts, as in the prior art, are not required, so the number of parts can be reduced accordingly. Thereby, the manufacturing cost of the operation mechanism 1 can be significantly reduced.

[0035] According to the present embodiment, since the above-described support structure and connecting gear structure are not required, a space for accommodating them is also not required. Thereby, the compactification of the operation mechanism 1 can be promoted.

[0036] According to the present embodiment, since the above-described support structure and the connecting gear structure are not required, a corresponding amount of space area can be secured. As a result, new components can be added to this space area.

[0037] According to the present embodiment, by performing the opening and closing operations between the electrodes 5 and 6 using only one screw shaft 8, the connecting gear structure and the support structure that were conventionally required are no longer necessary. As a result, alignment during assembly is not required, and consequently, the assemblability of the operating mechanism 1 can be improved.

[0038] According to the present embodiment, by extending the guide shaft 10 in parallel with one screw shaft 8, the rotational movement of the screw shaft 8 can be stably transmitted to the operating rod 12, and these operating rods 12 can be moved simultaneously. As a result, the electrodes 5 and 6 can be opened and closed with high reliability.

[0039] "Modification" FIG. 4 is a perspective configuration diagram of the operating mechanism 1 of the switchgear according to this modification and the switch gear including the operating mechanism 1, FIG. 5 is a plan configuration diagram thereof, and FIG. 6 is a cross-sectional configuration diagram thereof. In FIGS. 4 to 6, as an example, among the components of the switchgear, a three-phase electrode unit (R-phase electrode unit Re, S-phase electrode unit Se, T-phase electrode unit Te) is shown, and among the components of the switch gear, an operating mechanism for opening and closing the three-phase electrode units Re, Se, and Te is shown.

[0040] In the above-described embodiment, an operating mechanism 1 laid out around one screw shaft 8 was assumed. Instead of this, in this modification (FIGS. 4 to 6), the operating mechanism 1 is laid out with one screw shaft 8 being eccentric.

[0041] When viewed in a direction orthogonal to the opening and closing direction described above, the screw shaft 8 is provided in a positional relationship parallel to one (single) guide shaft 10. The screw shaft 8 and the guide shaft 10 have the same configuration as that of the above-described embodiment. A nut portion 9 is screwed onto the screw shaft 8. The guide shaft 10 is inserted through a bearing portion 11.

[0042] Also in this modified example, similar to the above-described embodiment, a connecting plate 13 is provided for moving (sliding) the three operating rods 12 at the same timing and with the same stroke. The connecting plate 13 is composed of a center region 13a that bisects the connecting plate 13 and side regions 13b and 13c on both sides of the center region 13a when viewed in a direction D2 orthogonal to the opening and closing direction D1.

[0043] In such a connecting plate 13, the nut portion 9 is fixed to one side region 13b, and the bearing portion 11 is fixed to the other side region 13c. Thereby, the screw shaft 8 to which the nut portion 9 is screwed is positioned between two adjacent operating rods 12 in one side region 13b. Further, the guide shaft 10 inserted through the bearing portion 11 is positioned between two adjacent operating rods 12 in the other side region 13c.

[0044] As described above, according to this modified example, with only one screw shaft 8, a plurality of movable electrodes 6 can be opened and closed simultaneously, smoothly, and with high reliability with respect to a plurality of fixed electrodes 5. Note that since other effects and configurations are the same as those of the above-described embodiment, the description thereof is omitted.

[0045] "Other Modifications" In the above-described embodiment, the case where the screw shaft 8 is positioned directly below the operating rod 12 is assumed, but instead, the screw shaft 8 may be positioned directly above the operating rod 12.

[0046] In this case, although not particularly shown in the drawings, when fixing the nut portion 9 to the center region 13a, the nut portion 9 may be positioned directly above the operation rod 12 positioned in the center region 13a when viewed in the direction D3 that is orthogonal to both the opening / closing direction D1 and the direction D2 orthogonal to the opening / closing direction D1. Thereby, in the center region 13a, the screw shaft 8 with which the nut portion 9 is screwed can be positioned directly below the operation rod 12. Note that since other effects and configurations are the same as those of the above-described embodiment, the description thereof is omitted.

[0047] "Other Modification Examples" In the above-described embodiment, the partition wall 2, the screw shaft 8, the nut portion 9, the guide shaft 10, the bearing portion 11, the operation rod 12, the connecting plate 13, the pair of support plates 14, and the bearing 15 were not mentioned in terms of their materials. However, all of these components may be made of an insulating material, or a part of these components may be made of an insulating material. In this case, for example, by configuring only the operation rod 12 with an insulating material, it is possible to prevent an electrical influence on the main circuit structure 3.

[0048] As described above, one embodiment and modification examples of the present invention have been explained. However, these embodiment and modification examples are presented as examples and are not intended to limit the scope of the invention. These embodiment and modification examples can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiment and modification examples are included in the scope and gist of the invention and are also included in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0049] Re…R-phase electrode unit, Se…S-phase electrode unit, Te…T-phase electrode unit, 1…operating mechanism, 2…partition wall, 3…main circuit structure, 4…operating structure, 5…fixed electrode, 6…movable electrode, 7…base plate, 8…screw shaft, 9…nut portion, 10…guide shaft, 11…bearing portion, 12…operating rod, 13…connecting plate, 13a…center region, 13b, 13c…side regions, 14…support plate, 15…bearing, D1…opening / closing direction, D2…direction orthogonal to the opening / closing direction, D3…direction orthogonal to both the opening / closing direction and the direction orthogonal to the opening / closing direction.

Claims

1. A movable electrode disposed to face the fixed electrode so as to be openable and closable, One rotatable screw shaft extending parallel to the opening and closing direction of the movable electrode and having a spiral cut formed on its surface, A nut portion screwed onto the screw shaft and movable along the screw shaft by rotating the screw shaft, A guide shaft extending parallel to the screw shaft, A bearing portion through which the guide shaft is inserted and movable along the guide shaft, An operation rod extending parallel to the opening and closing direction and having the movable electrode connected to one end thereof, A connecting plate extending in a direction perpendicular to the opening and closing direction and having the other end of the operation rod connected thereto, and The connecting plate is composed of a center region that bisects the connecting plate when viewed in a direction perpendicular to the opening and closing direction, and side regions on both sides of the center region, An operating mechanism of an opener in which the nut portion and the bearing portion are fixed to the connecting plate such that the screw shaft is positioned in either the center region or one of the side regions, and the guide shaft is positioned in the side region.

2. A plurality of the movable electrodes are arranged at intervals in a direction perpendicular to the opening and closing direction, The same number of operation rods as the movable electrodes are provided, and one end thereof is connected to each of the movable electrodes and the other end is connected to the connecting plate, The operating mechanism of the opener according to claim 1, wherein when viewed in a direction perpendicular to the opening and closing direction, the plurality of operation rods are arranged parallel to each other with the same interval as the interval between the movable electrodes.

3. The screw shaft is positioned in the center region, The operating mechanism of the opener according to claim 2, wherein the guide shaft is positioned one by one in the side regions on both sides of the screw shaft and between the operation rods.

4. The operating mechanism of the opener according to claim 3, wherein the screw shaft is positioned directly below or directly above the operation rod.

5. The screw shaft is positioned in the side region, The operating mechanism of the opener according to claim 2, wherein the guide shaft is positioned one in the side region on one side of the screw shaft and between the operation rods.

6. The operating mechanism of the opener according to claim 5, wherein the screw shaft is positioned between the operation rods.

7. A switchgear comprising an operating mechanism of a switch according to any one of claims 1 to 6, a partition wall partitioning the interior of the switchgear, a main circuit structure housed on one side of the partition wall and through which current flows during power reception and distribution, an operating structure housed on the other side of the partition wall and controlling the flow of current by operating the main circuit structure, the main circuit structure includes the movable electrode and the fixed electrode, a switchgear in which the operating structure includes the operating mechanism.

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