Ground terminal unit

Abstract

To provide a ground terminal unit in which a space in a distribution board can be efficiently ensured.SOLUTION: A terminal part 4 moves while being held by an ELB earth bar 2A and an MCB earth bar 2B. Thus, switching between a first connection state in which a connection part 13 is connected to the ELB ground bar 2A and a second connection state in which the connection part 13 is connected to the MCB ground bar 2B can be performed. A ground terminal unit 1 can perform a switching work during a held state in this manner, without removing the terminal part 4 from the ELB ground bar 2A and the MCB ground bar 2B. Accordingly, when the ground terminal unit 1 is installed in a distribution board 100, a space to be ensured for the switching work can be reduced.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an earth terminal unit. [Background technology]

[0002] There is known an earth terminal unit that is installed in a distribution board and to which an earth wire is connected. The earth terminal unit includes a pair of earth bars arranged parallel to each other and a terminal portion electrically connected to one of the earth bars (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-103317 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned earth terminal unit, the pair of belt-shaped earth bars are arranged so that their wide surfaces face each other. When switching the connection destination of the terminal unit, the worker removes the terminal unit from the earth bar to the front side, and inserts the terminal unit into the earth bar from the front side so that it is connected to the desired earth bar. In this way, when switching the earth bar to which the terminal unit is connected, the above-mentioned earth terminal unit restricts the insertion direction into the earth bar to the front side. Therefore, when the worker switches the connection state of the terminal unit, a space is required to perform the above-mentioned work, which causes a problem that the space in the distribution board cannot be effectively secured.

[0005] An object of the present invention is to provide an earth terminal unit that can effectively secure space within a distribution board. [Means for solving the problem]

[0006] The earth terminal unit of the present invention is an earth terminal unit that is installed in a distribution board and to which an earth wire is connected, and comprises a first earth bar and a second earth bar that are electrically independent of each other, a fixing portion that fixes the first earth bar and the second earth bar, and a terminal portion that has a connection portion that can be electrically connected to an earth wire and is held by the first earth bar and the second earth bar, and by moving the terminal portion while being held by the first earth bar and the second earth bar, it is possible to switch between a first connection state in which the connection portion is connected to the first earth bar and a second connection state in which the connection portion is connected to the second earth bar.

[0007] In the earth terminal unit according to the present invention, the terminal portion has a connection portion that can be electrically connected to the earth wire and is held by the first earth bar and the second earth bar. Therefore, the terminal portion can switch the earth bar to which the earth wire is electrically connected by switching the connection destination of the connection portion between the first earth bar and the second earth bar. Here, by moving the terminal portion while being held by the first earth bar and the second earth bar, it is possible to switch between a first connection state in which the connection portion is connected to the first earth bar and a second connection state in which the connection portion is connected to the second earth bar. In this way, the earth terminal unit enables the switching operation while the terminal portion is held in the first earth bar and the second earth bar without removing it from the first earth bar and the second earth bar. Therefore, the earth terminal unit can reduce the space to be reserved for the switching operation when installed in the distribution board. As described above, the earth terminal unit can effectively reserve the space in the distribution board.

[0008] The earth terminal unit of the present invention is an earth terminal unit that is installed in a distribution board and to which an earth wire is connected, and comprises a first earth bar and a second earth bar that are electrically independent of each other, a fixing portion that fixes the first earth bar and the second earth bar, and a terminal portion that has a connection portion that can be electrically connected to an earth wire and is held by the first earth bar and the second earth bar, and by moving the terminal portion while being held by the first earth bar and the second earth bar, it is possible to switch between a connected state in which the connection portion is connected to either the first earth bar or the second earth bar, and a non-connected state in which the connection portion is electrically independent from the first earth bar and the second earth bar.

[0009] In the earth terminal unit according to the present invention, the terminal portion has a connection portion that can be electrically connected to the earth wire and is held by the first earth bar and the second earth bar. Therefore, the terminal portion can electrically connect the earth wire to either of the earth bars by connecting the connection portion to either of the first earth bar and the second earth bar. When it is necessary to temporarily release the electrical connection between the earth wire and the earth bar, the terminal portion can make the connection portion electrically independent from either of the earth bars. Here, by moving the terminal portion while it is held by the first earth bar and the second earth bar, it is possible to switch between a connected state in which the connection portion is connected to either of the first earth bar and the second earth bar and a non-connected state in which the connection portion is electrically independent from the first earth bar and the second earth bar. In this way, the earth terminal unit allows the switching operation to be performed while the terminal portion is held by the first earth bar and the second earth bar without removing it from the first earth bar and the second earth bar. Therefore, when the earth terminal unit is installed in a distribution board, the space that must be reserved for switching operations can be reduced. As a result, the earth terminal unit can effectively secure space in the distribution board.

[0010] The first earth bar and the second earth bar may extend in a first direction and be arranged in parallel so as to be spaced apart from each other in a second direction perpendicular to the first direction, and the terminal part may be switched by sliding and moving in the second direction. In this case, the terminal part can perform switching only by moving in the second direction while maintaining the orientation of the earth wire. Therefore, the movement of the earth wire accompanying the switching operation can be suppressed.

[0011] The first earth bar and the second earth bar may extend in a first direction and be arranged in parallel so as to be spaced apart from each other in a second direction perpendicular to the first direction, and the terminal portion may be rotatably supported by a rotating shaft extending in the first direction, and the terminal portion may be switched by rotating about the rotating shaft and moving in the second direction. In this case, the orientation of the earth wire and the entire terminal portion changes as the terminal portion rotates about the rotating shaft. Therefore, an operator can easily recognize by visual inspection that the connection state of the terminal portion has been switched.

[0012] The cross-sectional shape of the first earth bar and the second earth bar may be circular. In this case, the cross-sectional shape of the first earth bar and the second earth bar has a constant diameter and a smooth curved surface over the entire circumference. Therefore, the structure for the terminal part to perform switching can be simplified, and the movement of the terminal part during switching can be made smooth. Effect of the Invention

[0013] According to the present invention, it is possible to provide an earth terminal unit that can effectively secure space within a distribution board. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic front view showing a distribution board to which the ground terminal unit according to the first embodiment is applied. [Diagram 2] FIG. 2 is a perspective view of the ground terminal unit according to the first embodiment. [Diagram 3]FIG. 3 is a front view of the ground terminal unit according to the first embodiment. [Figure 4] 4(a), (b), and (c) are diagrams showing the terminal portion in each state as viewed from the Y-axis direction. [Diagram 5] FIG. 5 is a diagram showing the terminal portion with the casing removed. [Figure 6] FIG. 6 is a perspective view of the ground terminal unit according to the second embodiment. [Figure 7] FIG. 7 is a front view of the ground terminal unit according to the second embodiment. [Figure 8] 8(a), (b), and (c) are diagrams of the terminal portion in each state as viewed from the Y-axis direction. [Figure 9] 13 is a schematic enlarged view showing a configuration of a through hole of a ground terminal unit according to a modified example. FIG. [Figure 10] FIG. 4 is a diagram showing an example of a cross-sectional shape of an earth bar. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are designated by the same reference numerals, and duplicated description will be omitted.

[0016] [First embodiment] FIG. 1 is a schematic front view showing a distribution board 100 to which a ground terminal unit 1 according to a first embodiment is applied. As shown in FIG. 1, the distribution board 100 includes internal devices such as a main breaker 101 and a branch breaker 102, and a ground terminal unit 1 in a housing 103. The main breaker 101 and the branch breakers 102 are attached to a mounting base (not shown) or the like provided in the housing 103. The main breaker 101 is a device that detects the current of the entire building and cuts off the circuit when an abnormality occurs. The branch breaker 102 is a breaker provided for a load device branched from the main breaker 101. The branch breaker 102 is a device that detects the current of a target load device and cuts off the circuit when an abnormality occurs. A plurality of branch breakers 102 are provided in an array in the distribution board 100.

[0017] The earth terminal unit 1 serves to ground the load device connected to the branch breaker 102. The earth terminal unit 1 may be attached to any member, such as a mounting base (not shown) in the housing 103 or a back panel of the housing 103. The earth terminal unit 1 is preferably provided at a position on the load side of the branch breaker 102. In the example shown in FIG. 1, the earth terminal unit 1 is provided in a space SP between the branch breaker 102 and a side surface 103a of the housing 103. By arranging the earth terminal unit 1 in the narrow space SP in this way, it is possible to prevent the earth terminal unit 1 from taking up space in the housing 103, and to ensure an effectively usable space in the housing 103.

[0018] FIG. 2 is a perspective view of the earth terminal unit 1. FIG. 3 is a front view of the earth terminal unit 1. As shown in FIG. 2 and FIG. 3, the earth terminal unit 1 includes an ELB earth bar 2A (first earth bar), an MCB earth bar 2B (second earth bar), installation stands 3A and 3B, and a plurality of terminal parts 4. Here, in the following description, the configuration of each component may be described using XYZ coordinates, which are relative coordinates set with respect to the earth terminal unit 1. The Y-axis direction (first direction) is a direction perpendicular to the X-axis direction (second direction). The Z-axis direction is a direction perpendicular to the X-axis direction and the Y-axis direction. In addition, one side of the X-axis direction, the Y-axis direction, and the Z-axis direction is referred to as the "positive side", and the other side is referred to as the "negative side". In the drawings, an arrow points from the negative side to the positive side on each axis.

[0019] The ELB earth bar 2A is an earth bar for grounding an Earth Leakage Breaker (ELB). The MCB earth bar 2B is an earth bar for grounding a Miniature Circuit Breaker (MCB). Among the branch breakers 102, those corresponding to Earth Leakage Breakers are connected to the ELB earth bar 2A. Among the branch breakers 102, those corresponding to molded circuit breakers are connected to the MCB earth bar 2B. The ELB earth bar 2A and the MCB earth bar 2B are electrically independent from each other. That is, the ELB earth bar 2A and the MCB earth bar 2B are arranged apart so as not to contact each other.

[0020] The earth bar 2A for the ELB and the earth bar 2B for the MCB extend in the Y-axis direction and are arranged in parallel to be spaced apart from each other in the X-axis direction. The earth bar 2A for the ELB and the earth bar 2B for the MCB are formed of conductive rod-shaped members extending linearly in the Y-axis direction. The earth bar 2A for the ELB and the earth bar 2B for the MCB are parallel to each other. In this embodiment, the earth bar 2A for the ELB is arranged on the positive side in the X-axis direction, and the earth bar 2B for the MCB is arranged on the negative side in the X-axis direction.

[0021] The ELB earth bar 2A and the MCB earth bar 2B are not members having a wide surface that spreads in a band shape, but are composed of members that extend linearly. When a cross-sectional shape of an oval, ellipse, or flat polygon is adopted as the linearly extending member, it is preferable to adopt a member in which the length a of the major axis is 200% or less of the length b of the minor axis as shown in FIG. 10, and it is more preferable to adopt a member in which the length a of the major axis is 150% or less. FIG. 10(a) shows a cross-sectional shape of an oval, and FIG. 10(b) shows a flat rectangle. Alternatively, it is more preferable to adopt a member having a cross-sectional shape that does not have a major axis and a minor axis, such as a circle and a regular polygon, as the linearly extending member. In this embodiment, the cross-sectional shape of the ELB earth bar 2A and the MCB earth bar 2B is a circle (see also FIG. 5). A circle is a shape that does not have a major axis and a minor axis. The size of the ELB earth bar 2A and the MCB earth bar 2B is not particularly limited. The material of the ELB earth bar 2A and the MCB earth bar 2B is not particularly limited, but copper or other metallic conductive materials are used.

[0022] The installation bases 3A and 3B are members for installing the earth terminal unit 1 on the distribution board 100. The installation base 3A is provided at the positive end of the ELB earth bar 2A and the MCB earth bar 2B in the Y-axis direction. The installation base 3B is provided at the negative end of the ELB earth bar 2A and the MCB earth bar 2B in the Y-axis direction. The installation bases 3A and 3B are approximately rectangular parallelepiped resin parts with the X-axis direction as the longitudinal direction. The resin material of the installation bases 3A and 3B is not particularly limited, but for example, resins such as nylon and polycarbonate are used. The negative side 3Aa of the installation base 3A in the Y-axis direction and the positive side 3Ba of the installation base 3B in the Y-axis direction face each other in the Y-axis direction so as to be parallel to each other.

[0023] The installation bases 3A, 3B each have a fixed portion 6 and an attachment portion 7. The fixed portion 6 is provided on the positive side of the installation bases 3A, 3B in the Z-axis direction. The attachment portion 7 is provided on the negative side of the installation bases 3A, 3B in the Z-axis direction. In this embodiment, the fixed portion 6 and the attachment portion 7 are configured as a single resin part that is integrally molded.

[0024] The fixing portion 6 is a portion for fixing the earth bar 2A for ELB and the earth bar 2B for MCB. The fixing portion 6 of the installation base 3A is fixed by embedding the portions of the earth bar 2A for ELB and the earth bar 2B for MCB near their ends on the positive side in the Y-axis direction in resin. The fixing portion 6 of the installation base 3B is fixed by embedding the portions of the earth bar 2A for ELB and the earth bar 2B for MCB near their ends on the negative side in the Y-axis direction in resin. The earth bar 2A for ELB and the earth bar 2B for MCB enter the inside of the fixing portion 6 from the side surface 3Aa of the installation base 3A, and enter the inside of the fixing portion 6 from the side surface 3Ba of the installation base 3B.

[0025] The fixing portion 6 of the installation stand 3A has notches 8A and 8B at both corners on the positive side in the Y-axis direction. The fixing portion 6 of the installation stand 3B has notches 8C and 8D at both corners on the negative side in the Y-axis direction. The notches 8A and 8C are formed on the positive side in the X-axis direction of each installation stand 3A and 3B. The notches 8A and 8C are provided with terminal plates 9A and 9C connected to the ELB earth bar 2A. The notches 8B and 8D are formed on the negative side in the X-axis direction of each installation stand 3A and 3B. The notches 8B and 8D (see FIG. 3) are provided with terminal plates 9B and 9D connected to the MCB earth bar 2B. The ELB earth bar 2A is connected to the terminal plates 9A and 9C by bending the portions near both ends in the Y-axis direction to the positive side in the X-axis direction inside the installation stand 3A and 3B. The MCB earth bar 2B is connected to the terminal boards 9B and 9D by bending portions near both ends in the Y-axis direction toward the negative side in the X-axis direction inside the installation bases 3A and 3B.

[0026] The mounting portion 7 is a portion for mounting the earth terminal unit 1 to the distribution board 100. The mounting portion 7 has a mounting surface 7a on the negative side in the Z-axis direction that comes into contact with a mounting base (not shown) in the housing 103 or a mounting target such as a back panel of the housing 103. The installation bases 3A and 3B are formed with cutouts 10 that penetrate in the Z-axis direction. The cutouts 10 are for passing bolts for fixing the installation bases 3A and 3B to the mounting target.

[0027] The terminal portion 4 is a member to which the earth electric wire 17 can be attached while being held by the ELB earth bar 2A and the MCB earth bar 2B. The terminal portion 4 is also a member that electrically connects the attached earth electric wire 17 to either the ELB earth bar 2A or the MCB earth bar 2B. In this embodiment, a plurality of terminal portions 4 (five in the figure) are held by the ELB earth bar 2A and the MCB earth bar 2B. The terminal portion 4 includes a main body portion 12 and a connection portion 13.

[0028] The main body 12 is a resin part of a substantially rectangular parallelepiped shape with the X-axis direction as the longitudinal direction. The resin material of the main body 12 is not particularly limited, but the same resin as that of the installation bases 3A and 3B is used. The main body 12 is formed by combining a casing 12A on the positive side in the Y-axis direction and a casing 12B on the negative side in the Y-axis direction. The casings 12A and 12B have a configuration in which the main body 12 is divided in half at the center position in the Y-axis direction. The main body 12 has a penetration part 16A through which the ELB earth bar 2A is inserted, and a penetration part 16B through which the MCB earth bar 2B is inserted. The penetration parts 16A and 16B penetrate the main body 12 from the main surface 12a on the positive side in the Y-axis direction of the main body 12 to the main surface 12b on the negative side in the Y-axis direction. The penetration part 16A is formed in a region of the main body 12 on the positive side in the X-axis direction, which is closer to the center position in the X-axis direction. The through portion 16B is formed in a region of the main body 12 on the negative side in the X-axis direction relative to the center position in the X-axis direction.

[0029] The main body 12 has a wiring hole 18 for inserting the earth wire 17 on a side surface 12c on the positive side in the Z-axis direction. The earth wire 17 is connected to the connection portion 13 inside the main body 12 by being inserted into the wiring hole 18.

[0030] The connection part 13 is a conductive member provided inside the main body part 12 and capable of being electrically connected to the earth wire 17. The material of the connection part 13 is not particularly limited, and may be the same as or a different material from the earth bars 2A and 2B. The connection part 13 can be connected by coming into contact with either the ELB earth bar 2A or the MCB earth bar 2B.

[0031] The configuration of the terminal portion 4 will be described in further detail with reference to Fig. 4. Figs. 4(a), (b), and (c) are diagrams of the terminal portion 4 in each state as viewed from the Y-axis direction. In this embodiment, by moving the terminal portion 4 while being held by the ELB earth bar 2A and the MCB earth bar 2B, it is possible to switch between a first connection state (state shown in Fig. 4(b)) in which the connection portion 13 is connected to the ELB earth bar 2A and a second connection state (state shown in Fig. 4(a)) in which the connection portion 13 is connected to the MCB earth bar 2B. In addition, by moving the terminal portion 4 while being held by the ELB earth bar 2A and the MCB earth bar 2B, it is possible to switch between a connected state (states shown in Figs. 4(a) and (b)) in which the connection portion 13 is connected to either the ELB earth bar 2A or the MCB earth bar 2B, and a non-connected state (state shown in Fig. 4(c)) in which the connection portion 13 is electrically independent from the ELB earth bar 2A and the MCB earth bar 2B. Furthermore, the terminal portion 4 can be switched between each state by sliding and moving in the X-axis direction.

[0032] Note that "the terminal portion 4 moves while being held by the earth bar 2A for the ELB and the earth bar 2B for the MCB" does not mean that the terminal portion 4 is removed from the earth bar 2A for the ELB and the earth bar 2B for the MCB and then reattached to the desired position, but rather that the terminal portion 4 moves while the earth bar 2A for the ELB and the earth bar 2B for the MCB remain inserted into the through-holes 16A, 16B.

[0033] In order to enable the above-mentioned switching, the through portion 16A of the terminal portion 4 has, in order from the center position in the X-axis direction toward the positive side, a contact portion 21A, a neutral portion 22A, and a retreat portion 23A. The contact portion 21A is a portion where the ELB earth bar 2A is arranged in the first connection state (see FIG. 4(b)), and is a portion for bringing the ELB earth bar 2A into contact with the connection portion 13. The neutral portion 22A is a portion where the ELB earth bar 2A is arranged in the non-connection state (see FIG. 4(c)), and is a portion for separating the ELB earth bar 2A from the connection portion 13. The retreat portion 23A is a portion where the ELB earth bar 2A is arranged in the second connection state (see FIG. 4(a)), and is a portion for retracting and separating the ELB earth bar 2A from the connection portion 13.

[0034] When viewed from the Y-axis direction, the inner peripheral surfaces of the contact portion 21A, the neutral portion 22A, and the retraction portion 23A have a circular shape corresponding to the circular cross-sectional shape of the ELB earth bar 2A. At the boundary between the contact portion 21A and the neutral portion 22A, the internal space of the contact portion 21A and the internal space of the neutral portion 22A are connected. At the boundary between the retraction portion 23A and the neutral portion 22A, the internal space of the retraction portion 23A and the internal space of the neutral portion 22A are connected. At the boundary between the contact portion 21A and the neutral portion 22A and the boundary between the retraction portion 23A and the neutral portion 22A, a stopper portion 24A is formed by a constriction formed by the circular internal spaces communicating with each other. The stopper portion 24A restricts the ELB earth bar 2A arranged at any one of the contact portion 21A, the neutral portion 22A, and the retraction portion 23A from moving relatively to an adjacent portion.

[0035] Here, the main body 12 has a slit 26A corresponding to the shape of the inner circumferential surface at a position offset from the inner circumferential surface on the positive side in the Z-axis direction of the neutral portion 22A and the retreat portion 23A toward the positive side in the Z-axis direction (see also FIG. 5). Therefore, the positive side of the neutral portion 22A and the retreat portion 23A in the Z-axis direction functions as a movable portion 27A that moves with the movement of the ELB earth bar 2A. For example, when the ELB earth bar 2A moves from the retreat portion 23A to the neutral portion 22A over the stopper portion 24A, the movable portion 27A moves so that the gap between the stopper portions 24A widens. In this embodiment, the slit 26A and the movable portion 27A are formed only in the casing 12B. The casing 12A is largely cut out at a position corresponding to the slit 26A and the movable portion 27A.

[0036] The receiving portion 31A of the connection portion 13 is arranged so as to be exposed on the inner peripheral surface of the contact portion 21A. The receiving portion 31A has a C-shape when viewed from the Y-axis direction, and is opened at the boundary between the contact portion 21A and the neutral portion 22A so that the ELB earth bar 2A can enter the receiving portion 31A. The diameter of the inner peripheral surface of the receiving portion 31A is approximately the same as the diameter of the ELB earth bar 2A. The size of the receiving portion 31A is set so that the receiving portion 31A and the ELB earth bar 2A do not come into contact with each other when the ELB earth bar 2A is arranged in the neutral portion 22A.

[0037] The through portion 16B of the terminal portion 4 has, in this order from the center position in the X-axis direction toward the negative side, a contact portion 21B, a neutral portion 22B, and a retraction portion 23B. The contact portion 21B is a portion where the MCB earth bar 2B is disposed in the second connected state (see FIG. 4(a)) and is a portion for contacting the MCB earth bar 2B with the connection portion 13. The neutral portion 22B is a portion where the MCB earth bar 2B is disposed in the non-connected state (see FIG. 4(c)) and is a portion for separating the MCB earth bar 2B from the connection portion 13. The retraction portion 23B is a portion where the MCB earth bar 2B is disposed in the first connected state (see FIG. 4(b)) and is a portion for retracting the MCB earth bar 2B from the connection portion 13 and separating it.

[0038] The through portion 16B has a structure symmetrical with respect to the center position in the X-axis direction with respect to the through portion 16A. Therefore, the through portion 16B has a stopper portion 24B, a receiving portion 31B, a slit 26B, and a movable portion 27B that have the same configurations as the stopper portion 24A, the receiving portion 31A, the slit 26A, and the movable portion 27A of the through portion 16A.

[0039] The contact portion 21A, the neutral portion 22A, and the retreat portion 23A of the through portion 16A, and the contact portion 21B, the neutral portion 22B, and the retreat portion 23B of the through portion 16B are linearly arranged along the X-axis direction at the center position in the Z-axis direction. Specifically, the central axes of the contact portion 21A, the neutral portion 22A, the retreat portion 23A, the contact portion 21B, the neutral portion 22B, and the retreat portion 23B are arranged on a virtual straight line (see virtual line L1 in FIG. 4(a)) extending in the X-axis direction when viewed from the Y-axis direction. Therefore, the terminal portion 4 can slide linearly in the X-axis direction relative to the ELB earth bar 2A and the MCB earth bar 2B arranged in the X-axis direction. The sliding movement of the terminal portion 4 means that the terminal portion 4 moves straight without including a rotational component in the moving direction.

[0040] Next, the configuration of the connection part 13 will be described in more detail with reference to FIG. 5. FIG. 5 is a diagram showing the terminal part 4 with the casing 12B removed. The connection part 13 has the above-mentioned receiving parts 31A and 31B, the connecting part 32, and the holding parts 33A and 33B. The connecting part 32 is a part that connects the receiving part 31A and the receiving part 31B. The connecting part 32 extends from the receiving part 31A to the negative side in the Z-axis direction, extends to the negative side in the X-axis direction, and extends toward the receiving part 31B to the positive side in the Z-axis direction, thereby connecting the receiving parts 31A and 31B to each other. The connecting part 32 is supported by the wall part 37 of the casing 12B. The holding parts 33A and 33B are parts that hold the earth electric wire 17 inserted from the wiring hole 18. The holding parts 33A and 33B are formed by raising some of the conductor pieces of the receiving parts 31A and 31B toward the center side in the X-axis direction. The ground wire 17 inserted from the wiring hole 18 passes between the holding parts 33A, 33B while pushing aside the holding parts 33A, 33B, and reaches the position of the coupling part 32. As a result, the ground wire 17 is sandwiched and held by the holding parts 33A, 33B, and is electrically connected to the connection part 13.

[0041] Returning to FIG. 4, the switching operation of the terminal portion 4 will be described. When the terminal portion 4 is in a non-connected state, as shown in FIG. 4(c), the ELB earth bar 2A is disposed in the neutral portion 22A, and the MCB earth bar 2B is disposed in the neutral portion 22B. At this time, the connection portion 13 is not connected to any of the earth bars 2A and 2B. In FIG. 2 and FIG. 3, the three terminal portions 4 on the positive side in the Y-axis direction are in a non-connected state. When switching from such a non-connected state to the first connected state, the worker slides the terminal portion 4 to the positive side in the X-axis direction. As a result, as shown in FIG. 4(b), the ELB earth bar 2A is disposed in the contact portion 21A, and the MCB earth bar 2B is disposed in the retracted portion 23B. At this time, the connection portion 13 is connected to the ELB earth bar 2A at the receiving portion 31A, and is not connected to the MCB earth bar 2B. In FIG. 2 and FIG. 3, the terminal portion 4 on the most negative side in the Y-axis direction is in the first connected state. When switching from the first connection state to the second connection state, the worker slides the terminal portion 4 to the negative side in the X-axis direction. As a result, as shown in Fig. 4(a), the ELB earth bar 2A is disposed in the retracted portion 23A, and the MCB earth bar 2B is disposed in the contact portion 21B. At this time, the connection portion 13 is connected to the MCB earth bar 2B at the receiving portion 31B, and is not connected to the ELB earth bar 2A. In Figs. 2 and 3, the second terminal portion 4 counting from the negative side in the Y-axis direction is in the second connection state.

[0042] Next, the operation and effect of the ground terminal unit 1 according to the first embodiment will be described.

[0043] In the earth terminal unit 1 according to the present embodiment, the terminal portion 4 has a connection portion 13 that can be electrically connected to the earth wire 17, and is held by the ELB earth bar 2A and the MCB earth bar 2B. Therefore, the terminal portion 4 can switch the earth bars 2A and 2B to which the earth wire 17 is electrically connected by switching the connection destination of the connection portion 13 between the ELB earth bar 2A and the MCB earth bar 2B. Here, by moving the terminal portion 4 while being held by the ELB earth bar 2A and the MCB earth bar 2B, it is possible to switch between a first connection state in which the connection portion 13 is connected to the ELB earth bar 2A and a second connection state in which the connection portion 13 is connected to the MCB earth bar 2B. In this way, the earth terminal unit 1 enables the switching operation while the terminal portion 4 is held without removing it from the ELB earth bar 2A and the MCB earth bar 2B. Therefore, the earth terminal unit 1 can reduce the space to be secured for the switching operation when installed in the distribution board 100. As described above, in the ground terminal unit 1, the space inside the distribution board 100 can be effectively secured.

[0044] In the earth terminal unit 1 according to this embodiment, the terminal portion 4 has a connection portion 13 electrically connectable to the earth wire 17, and is held by the ELB earth bar 2A and the MCB earth bar 2B. Therefore, the terminal portion 4 can electrically connect the earth wire 17 to either the ELB earth bar 2A or the MCB earth bar 2B by connecting the connection portion 13 to either the ELB earth bar 2A or the MCB earth bar 2B. When it is necessary to temporarily release the electrical connection between the earth wire 17 and the earth bars 2A and 2B, the terminal portion 4 may have the connection portion 13 electrically isolated from either the earth bars 2A and 2B. Here, by moving the terminal portion 4 while being held by the ELB earth bar 2A and the MCB earth bar 2B, it is possible to switch between a connection state in which the connection portion 13 is connected to either the ELB earth bar 2A or the MCB earth bar 2B, and a non-connection state in which the connection portion 13 is electrically independent from the ELB earth bar 2A and the MCB earth bar 2B. In this way, the earth terminal unit 1 enables the switching operation while the terminal portion 4 is held without removing it from the ELB earth bar 2A and the MCB earth bar 2B. Therefore, the earth terminal unit 1 can reduce the space to be reserved for the switching operation when installed in the distribution board 100. As described above, the earth terminal unit 1 can effectively reserve the space in the distribution board 100.

[0045] The ELB earth bar 2A and the MCB earth bar 2B extend in the Y-axis direction and are arranged in parallel to be spaced apart from each other in the X-axis direction perpendicular to the Y-axis direction, and the terminal unit 4 may be switched by sliding and moving in the X-axis direction. In this case, the terminal unit 4 can be switched only by moving in the X-axis direction while maintaining the orientation of the earth electric wire 17. Therefore, the movement of the earth electric wire 17 accompanying the switching operation can be suppressed.

[0046] In addition, in the earth terminal unit 1, the positions of the earth wire 17 and the entire terminal portion 4 relative to the earth bars 2A, 2B change due to the switching operation. Therefore, the worker can easily recognize by visual inspection that the connection state of the terminal portion 4 has been switched.

[0047] The cross-sectional shape of the earth bar 2A for the ELB and the earth bar 2B for the MCB may be circular. In this case, the cross-sectional shape of the earth bar 2A for the ELB and the earth bar 2B for the MCB has a constant diameter and a smooth curved surface over the entire circumference. Therefore, the structure for the terminal part 4 to perform switching can be simplified, and the movement of the terminal part 4 during switching can be made smooth.

[0048] [Second embodiment] Fig. 6 is a perspective view of an earth terminal unit 200 according to the second embodiment. Fig. 7 is a front view of the earth terminal unit 200. The earth terminal unit 200 according to the second embodiment differs from the terminal portion 4 of the earth terminal unit 1 according to the first embodiment in the manner in which the terminal portion 204 moves. Below, of the configuration of the earth terminal unit 200 according to the second embodiment, points that differ from the earth terminal unit 1 according to the first embodiment will be described, and a description of points in common will be omitted.

[0049] The terminal portion 204 is rotatably supported by a rotation shaft 250 extending in the Y-axis direction. The rotation shaft 250 extends parallel to the Y-axis direction between the installation base 3A and the installation base 3B, and penetrates each terminal portion 204. The penetration portions 216A and 216B formed in the terminal portion 204 have a structure that enables the rotation of the terminal portion 204. As a result, the terminal portion 204 can be switched between a first connected state, a second connected state, and a non-connected state by rotating around the rotation shaft 250 and moving in the X-axis direction.

[0050] As shown in FIG. 8(c), the contact portion 221A, the neutral portion 222A, and the retreat portion 223A of the through portion 216A and the contact portion 221B, the neutral portion 222B, and the retreat portion 223B of the through portion 216B are arranged to draw an arc with the rotation axis 250 as the center. Specifically, the central axes of the contact portion 221A, the neutral portion 222A, the retreat portion 223A, the contact portion 221B, the neutral portion 222B, and the retreat portion 223B are arranged on a virtual arc (see virtual line L2 in FIG. 8(a)) with the rotation axis 250 as the center when viewed from the Y-axis direction. Therefore, the terminal portion 204 can rotate around the rotation axis 250 and move in the X-axis direction with respect to the ELB earth bar 2A and the MCB earth bar 2B arranged in the X-axis direction. The term "terminal portion 204 moves while rotating" means that terminal portion 204 moves in a state where the direction of movement includes a rotational component.

[0051] The switching operation of the terminal portion 204 will be described with reference to FIG. 8. When the terminal portion 204 is in a non-connected state, as shown in FIG. 8(c), the ELB earth bar 2A is disposed in the neutral portion 222A, and the MCB earth bar 2B is disposed in the neutral portion 222B. At this time, the connection portion 13 is not connected to any of the earth bars 2A and 2B. In FIG. 6 and FIG. 7, the three terminal portions 204 on the positive side in the Y-axis direction are in a non-connected state. When switching from such a non-connected state to the first connected state, the worker rotates the terminal portion 204 to the positive side in the X-axis direction. As a result, as shown in FIG. 8(b), the ELB earth bar 2A is disposed in the contact portion 221A, and the MCB earth bar 2B is disposed in the retracted portion 223B. At this time, the connection portion 13 is connected to the ELB earth bar 2A at the receiving portion 31A, and is not connected to the MCB earth bar 2B. In Fig. 6 and Fig. 7, the second terminal 204 counting from the negative side in the Y-axis direction is in the first connection state. When switching from the first connection state to the second connection state, the worker rotates the terminal 204 to the negative side in the X-axis direction. As a result, as shown in Fig. 8(a), the ELB earth bar 2A is disposed in the retracted portion 223A, and the MCB earth bar 2B is disposed in the contact portion 221B. At this time, the connection portion 13 is connected to the MCB earth bar 2B at the receiving portion 31B, and is not connected to the ELB earth bar 2A. In Fig. 6 and Fig. 7, the terminal 204 on the most negative side in the Y-axis direction is in the second connection state.

[0052] As described above, the terminal portion 204 may be rotatably supported by the rotation shaft 250 extending in the Y-axis direction, and the terminal portion 204 may be switched by rotating about the rotation shaft 250 and moving in the X-axis direction. In this case, the rotation of the terminal portion 204 about the rotation shaft 250 changes the posture of the earth wire 17 and the entire terminal portion 204 (see FIGS. 6 and 7). Therefore, the worker can easily recognize by visual inspection that the connection state of the terminal portion 204 has been switched.

[0053] The present invention is not limited to the above-described embodiments.

[0054] For example, in the above-described embodiment, the earth terminal unit has two earth bars, but it may have three or more earth bars and may be capable of switching the connection state to these earth bars.

[0055] Furthermore, the configuration of the through-hole of the terminal portion for switching the state is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

[0056] For example, in the above-described embodiment, the neutral portion was positioned between the contact portion and the retraction portion, but by devising the shape of the receiving portion of the connection portion, the neutral portion may be configured to be positioned outside the contact portion and the retraction portion.

[0057] In the above-described embodiment, each switching operation is performed by moving in the X-axis direction, which is the arrangement direction of the earth bars 2A and 2B. However, switching to each state may be performed by moving the terminal portion in the Z-axis direction. For example, as shown in FIG. 9(a), the contact portion 321 and the retracted portion 323 may be adjacent to each other in the X-axis direction, and the neutral portion 322 may be disposed in a position adjacent to the contact portion 321 and the retracted portion 323 in the Z-axis direction. In this case, when switching from the connected state to the non-connected state, the terminal portion moves to the negative side in the Z-axis direction. In addition, by devising the arrangement of the receiving portion of the connection portion, switching between the first connected state and the second connected state may be performed by moving in the Z-axis direction.

[0058] For example, a protruding stopper portion is provided at the boundary portion of the contact portion, the neutral portion, and the retreat portion, so that the earth bar is fixed at each portion. However, the mechanism for stopping the movement of the earth bar is not particularly limited. For example, as shown in FIG. 9(b), a mechanism for fixing the earth bar 2 in place by an operator's operation or the like may be provided without providing a protrusion such as a stopper portion at the boundary portion of the contact portion 421, the neutral portion 422, and the retreat portion 423. For example, a pressing mechanism 430 may be provided in which the operator presses the earth bar 2 by performing an operation such as screwing, thereby fixing the earth bar 2 in place at each position of the contact portion 421, the neutral portion 422, and the retreat portion 423.

[0059] For example, a terminal portion dedicated to the ELB earth bar 2A may be provided. The terminal portion may have only a contact portion with the ELB earth bar 2A and a neutral portion, and may be configured to only switch between the first connection state and the non-contact state. [Explanation of symbols]

[0060] 1,200...Earth terminal unit, 2A...Earth bar for ELB (first earth bar), 2B...Earth bar for MCB (second earth bar), 4,204...Terminal part, 6...Fixed part, 17...Earth wire, 100...Distribution board, 250...Rotating shaft.

Claims

1. An earth terminal unit that is installed in a distribution board and to which an earth wire is connected, a first earth bar and a second earth bar which are electrically independent from each other; a fixing portion that fixes the first earth bar and the second earth bar; a terminal portion having a connection portion electrically connectable to the earth wire and held by the first earth bar and the second earth bar; An earth terminal unit in which the terminal portion can be moved while being held by the first earth bar and the second earth bar, thereby switching between a first connection state in which the connection portion is connected to the first earth bar and a second connection state in which the connection portion is connected to the second earth bar.

2. An earth terminal unit that is installed in a distribution board and to which an earth wire is connected, a first earth bar and a second earth bar which are electrically independent from each other; a fixing portion that fixes the first earth bar and the second earth bar; a terminal portion having a connection portion electrically connectable to the earth wire and held by the first earth bar and the second earth bar; An earth terminal unit in which the terminal portion can be moved while being held by the first earth bar and the second earth bar, thereby switching between a connected state in which the connection portion is connected to either the first earth bar or the second earth bar, and a non-connected state in which the connection portion is electrically independent from the first earth bar and the second earth bar.

3. The first earth bar and the second earth bar extend in a first direction and are arranged in parallel to each other so as to be spaced apart from each other in a second direction perpendicular to the first direction, The earth terminal unit according to claim 1 , wherein the terminal portion is slidably moved in the second direction to enable the switching.

4. The first earth bar and the second earth bar extend in a first direction and are arranged in parallel to each other so as to be spaced apart from each other in a second direction perpendicular to the first direction, the terminal portion is rotatably supported by a rotation shaft extending in the first direction, The earth terminal unit according to claim 1 , wherein the terminal portion is capable of being switched by rotating about the rotation axis and moving in the second direction.

5. The earth terminal unit according to any one of claims 1 to 4, wherein the first earth bar and the second earth bar have a circular cross-sectional shape.

Images