JP4683903B2 - Current transformer for measuring instrument - Google Patents

Description

  The present invention relates to a current transformer for a measuring instrument, and in particular, relates to a connecting body used in this current transformer for a measuring instrument that is formed in an annular shape by sequentially connecting core units.

  2. Description of the Related Art Conventionally, there is known a clamp meter that surrounds a distribution line (wiring) by sequentially connecting a plurality of cores in a joint shape and can detect a current flowing through the wiring (see, for example, Patent Document 1).

If the conventional clamp meter is used, the current flowing through the wiring is measured even if the wiring itself is large, the distance between the wirings is wide, or even if the wiring is installed at a place where measurement is difficult such as near a wall. can do.
See Japanese Patent No. 2839870

  However, the conventional clamp meter is in an annular shape at the time of measurement, and the coil is installed only in a very small part of the core surrounding the wiring. Therefore, the measurement accuracy is low and may not be used in a situation where current is accurately measured. . In addition, since the conventional clamp meter cannot easily adjust the length of the core, the shape of the core cannot be easily changed in accordance with the shape of the wiring, which may be difficult to use. Furthermore, there is a problem that the connection quantity of the cores that are annular has not been improved.

  Therefore, as shown in Japanese Patent Application No. 2004-167309, a coil is provided in each core unit, and these core units are sequentially connected to each other to constitute a coupling body. In this proposed apparatus, since all the cores are provided with coils, the current flowing through the wiring can be accurately measured, and the core units can be connected to each other at connection points or disconnected. In addition, one core unit can be rotated with respect to the other core unit at the connecting portion.

  However, in the proposed apparatus, the core units are connected to each other and released from the connection, failure due to exposure of electrical components such as coils, and securing of strength necessary for measuring the connection part (connection part). There is a problem that the problem as a current transformer (product) is unresolved.

  Therefore, a method of surrounding the connecting body with a cover member to avoid the possibility of scratching the coil or the like is conceivable. However, as described above, the joint portion between the core units constituting the connecting body rotates. Therefore, even when the coupling body (core unit) is surrounded by a cover member, it is necessary to allow the core unit to rotate and to protect the wiring such as a coil with the rotating portion. .

  The need for wiring protection occurs not only in the clamp meter, but also in current transformers for measuring instruments such as zero-phase current transformers that can detect leakage from the wiring.

  The present invention has been made in view of the above-mentioned necessity, and according to the form of the wiring, the form of the coupling body can be easily changed, and the current flowing through the wiring can be accurately measured, An object of the present invention is to provide a current transformer for a measuring instrument that can protect the wiring of the core unit even at the joint portion of the core unit that can be easily detached and rotated.

  According to the first aspect of the present invention, in a current transformer for a measuring instrument capable of detecting a current flowing through a wiring in a state of being electrically non-contact with the wiring, the casing is provided inside the casing. A core unit having an iron core and a core unit wound around the iron core and provided inside the casing is provided with a connecting body configured by joining together, and the core unit is The core unit is engaged with the other core unit so that it can be easily attached and detached and is freely rotatable. When the core units are joined to each other to form the coupling body, the coupling body surrounds the wiring. The iron core is configured to detect a current flowing through the wiring, and when one of the core units joined to each other rotates with respect to the other core unit, the iron core , Cover for the terminal portions of Le and the coil is prevented from exposure, a measuring instruments current transformer is provided in the housing.

  According to a second aspect of the present invention, there is provided a current transformer for a measuring instrument capable of detecting a current flowing through a wiring in an electrically non-contact state with the wiring, and a rectangular and cylindrical housing having both ends opened. A plurality of core units each having a body, an iron core provided inside the housing, and a coil wound around the iron core and provided inside the housing. The end of the core unit in the longitudinal direction, which is a direction connecting the openings of the core unit to each other, is easily attached to and detached from the end of the other core unit, It is engaged so as to be rotatable about an axis extending in the width direction, which is an orthogonal direction, and when the core units are joined to each other to form a connection body, the wiring is connected with the connection body. Enclose the current flowing through the wiring The rotation angles of the core units joined to each other are set so that each core unit is in a straight line shape, and the other core unit is one with respect to the other core unit. Is rotated by a predetermined angle in one direction, and is one surface of the thickness direction that is a direction perpendicular to the longitudinal direction and the width direction and is rotated by the predetermined angle. On the convex side, the first cover unit is provided on the casing of the one core unit to be joined, and the second cover part is provided on the other core unit to be joined. In a state where the core units are joined to each other, at least a part of the first cover part and at least a part of the second cover part overlap each other, and the joined core units are Linear For the measuring instrument configured such that the overlapping portions of the respective cover portions are formed larger and the overlapping portions of the respective cover portions become smaller as the rotation angle increases. It is a current transformer.

  According to a third aspect of the present invention, in the current transformer for a measuring instrument according to the second aspect, the first cover portion is separated from the main body portion of the housing and is configured in a plate shape, and a proximal end It is provided so as to be rotatable with respect to the main body of the housing on the part side, and in the state where the first cover is closed, it is one surface in the thickness direction of the housing and the first The surface on which the cover portion is provided and the first cover portion are substantially in the same plane, and when the first cover portion is open, the longitudinal direction of the housing An opening is formed on one side of the end of the cover and on the convex side in the thickness direction, and an engagement portion formed on the main body of the housing is engaged with the front end of the cover. A locked portion to be joined is formed, and the first cover portion is in a state where the locking portion and the locked portion are engaged with each other. Kikatamitai a body portion and in which measuring instruments current transformer adapted to be integrally connected.

  According to a fourth aspect of the present invention, in the current transformer for a measuring instrument according to the third aspect, a portion of the housing where the first cover portion is installed is closed by the first cover portion. In the state, the shape of the cross section by the plane perpendicular to the longitudinal direction is formed in a “U” shape, and both end portions in the width direction of the first cover portion on the tip end side of the first cover portion In the state where the protrusion that slightly protrudes in the width direction and forms the locked portion is provided via the locked portion support portion, and the first cover portion is closed, The locked portion support portion and the locked portion enter the inside of the housing, and the protrusions constituting the locked portion are both end portions in the width direction of the body portion of the housing The first cover portion is aligned with the main body portion of the housing. The main body portion of the casing is configured by a base portion having a cross-sectional shape formed by a plane perpendicular to the longitudinal direction and a flat lid portion. The first cover portion is rotatably engaged with the lid portion on one side of the end portion in the longitudinal direction of the lid portion, and the locking portion of the main body portion of the casing and the first cover portion This is a current transformer for a measuring instrument provided with a spread preventing mechanism for preventing the main body portion of the casing from spreading too much in the width direction when engaging with the locked portion of the cover portion.

  According to a fifth aspect of the present invention, in the current transformer for a measuring instrument according to the fourth aspect, the lid and the base are assembled in such a manner that the opening side of the “U” -shaped base is slightly in the width direction. This is performed by engaging the protrusions protruding on both sides in the width direction of the lid portion with the recesses provided in the walls existing at both ends in the width direction of the base portion while being elastically deformed. The spread prevention mechanism is configured by a projection provided on each end side in the width direction of the base and a recess provided on the lid and engaged with the projection of the base. In order to make it easy to assemble the lid part to the base part, a protrusion and a concave part constituting the spread prevention mechanism, and the protrusion part and the base part of the lid part provided to assemble the lid part to the base part The distance between the concave part of the Measuring instruments is a current transformer.

  According to a sixth aspect of the present invention, in the current transformer for a measuring instrument according to the second aspect, the first cover portion is separated from the main body portion of the housing and is configured in a plate shape, and a proximal end It is provided so as to be rotatable with respect to the main body of the housing on the part side, and in the state where the first cover is closed, it is one surface in the thickness direction of the housing and the first The surface on which the cover portion is provided and the first cover portion are substantially in the same plane, and when the first cover portion is open, the longitudinal direction of the housing An opening is formed on one side of the end of the projection and on the convex side in the thickness direction, and the portion of the housing where the first cover is installed is the first cover In the closed state, the cross-sectional shape by a plane perpendicular to the longitudinal direction is formed in a “U” shape, and the first cover portion On the base end side, a cylindrical portion extending in the width direction with a slit extending in the width direction is provided, and an end that engages with the first cover portion of the main body portion of the housing On the part side, when the lid portion and the first cover portion are assembled to each other, a central shaft portion that extends into the center portion of the cylindrical portion extends in the width direction, and the first portion A notch for allowing a part of the cylindrical portion to enter when the cover portion of 1 is rotated is provided adjacent to the central shaft portion and parallel to the central shaft portion, and the width of the slit is It is slightly smaller than the outer diameter of the central shaft portion, and the lid portion and the first cover portion are mutually connected in a state where the lid portion and the first cover portion exist on one plane. When assembled close together, the cylindrical part is elastically deformed and the slit is slightly Rising the center shaft enters the inside of the cylindrical portion, a measuring instruments current transformer the first cover portion is configured to grapple with the lid.

  According to a seventh aspect of the present invention, in the current transformer for a measuring instrument according to the third aspect, the first cover portion is closed at a portion of the housing where the first cover portion is installed. In the state, the shape of the cross section by a plane perpendicular to the longitudinal direction is formed in a “U” shape, and a slit extending in the width direction is provided on the base end side of the first cover portion in the width direction. A cylindrical portion extending to the first cover portion is provided on the end portion side of the main body portion of the casing that engages with the first cover portion. When assembled, a central shaft portion that enters the central portion of the cylindrical portion is provided to extend in the width direction, and when the first cover portion rotates, a part of the cylindrical portion is formed. A notch for entering is provided adjacent to the central shaft portion and parallel to the central shaft portion, The width of the slit is slightly smaller than the outer diameter of the central shaft, and the lid and the first cover are in a state where the lid and the first cover are on one plane. When the cylindrical cover part is assembled close to each other, the cylindrical part is elastically deformed, the slit slightly expands, the central shaft part enters the inside of the cylindrical part, and the first cover part is inserted into the lid part. Is a current transformer for a measuring instrument configured to be assembled.

  The invention according to claim 8 is the current transformer for measuring instrument according to any one of claim 4 or claim 5, wherein the first cover portion extends in the width direction on the base end side. A cylindrical portion that is provided with a slit and extends in the width direction is provided, and the lid portion and the first portion are provided on an end portion side of the main body portion of the housing that engages with the first cover portion. When the first cover part is rotated, a central shaft part that extends into the center part of the cylindrical part is provided to extend in the width direction when the first cover part is rotated. A notch for allowing a part of the shaped portion to enter is provided adjacent to the central shaft portion and parallel to the central shaft portion, and the width of the slit is slightly smaller than the outer diameter of the central shaft portion. A state in which the lid portion and the first cover portion are present on a single plane. When the lid portion and the first cover portion are assembled close to each other, the cylindrical portion is elastically deformed so that the slit slightly extends and the central shaft portion enters the inside of the cylindrical portion, and the lid portion It is a current transformer for measuring instruments comprised so that the said 1st cover part may be assembled | attached.

  A ninth aspect of the present invention is the measuring instrument current transformer according to any one of the second to eighth aspects, wherein the current transformer is rotated on the one surface in the thickness direction by the predetermined angle. The inner side cover of the elastic body is provided to prevent a gap due to the rotation of the core unit between the core units joined to each other. It is a fluency.

  According to the present invention, in the measuring instrument current transformer capable of detecting the current flowing through the wiring in an electrically non-contact state with the wiring, the configuration of the coupling body is easily changed according to the configuration of the wiring. Thus, the current flowing through the wiring can be accurately measured, and the core unit wiring can be protected even at the joint portion of the core unit that can be easily detached and rotated.

  FIG. 1 is a perspective view showing an overview of a core unit 1 constituting a connection body 3 of a current transformer for measuring instrument according to an embodiment of the present invention, and FIG. 2 is a connection body 3 constituted by the core unit 1. FIG.

  3A is a view taken in the direction of arrow IIIA in FIG. 2, FIG. 3B is a view taken in the direction of arrow IIIB in FIG. 2, and FIG. 4 is a current transformer for measuring instrument (zero-phase current transformer 5). FIG.

  FIG. 5 is a perspective view showing an overview of the casing 7 constituting the core unit 1, and FIG. 6 is a perspective view showing an overview of the iron core 9 and the coil 11 provided inside the casing 7. is there.

  FIG. 5 shows a state in which the housing 7 is disassembled, and the housing 7 is formed in a rectangular cylindrical shape in the assembled state.

  As shown in FIG. 2, the measuring instrument current transformer is capable of detecting the current flowing through the wiring (distribution line) CB in an electrically non-contact state with the wiring CB. In the present embodiment, the zero-phase current transformer 5 capable of detecting a leakage from the wiring CB will be described as an example.

  The zero-phase current transformer 5 includes a connecting body 3. As shown in FIG. 2, the coupling body 3 is configured by sequentially joining a plurality of core units 1 to each other.

  The end portion of the core unit 1 is easily attached to and detached from the other end portions of the core unit 1 and is engaged in a joint shape (for example, rotatably engaged). When the core units 1 are joined to each other to form the connection body 3, the connection body 3 surrounds the wiring CB, that is, the wiring CB extends and passes through the inside of the annular connection body 3. As described above, the connection body 3 surrounds the wiring CB so that a current flowing through the wiring CB can be detected.

  The core unit 1 includes a rectangular and cylindrical casing 7 having openings 1A and 1B at both ends, an iron core 9 provided inside the casing 7, and the iron core (each of the longitudinal directions). And a coil 11 wound around the tip 9 and provided inside the housing 7 (FIGS. 1, 5, 6, and 9B). reference).

  When the core units 1 are joined to each other, as will be described in detail later, the iron cores 9 are joined together and the coils 11 are also electrically joined together (see FIG. 4).

  Further, the zero-phase current transformer 5 is provided with a signal line 15 that outputs from the coupling body 3 to an insulation monitoring device 13 including, for example, a secondary burden resistor 11a (see FIGS. 2 and 4). And the electric current which generate | occur | produced in the said coil 11 is detected by the said insulation monitoring apparatus 13, and it can detect the electric leakage of the said wiring CB.

  The signal line 15 is, on the connecting body 3 side, a substantially central portion in the longitudinal direction of the core unit 1a (one core unit 1a among the core units 1 constituting the connecting body 3). The core unit 1a extends in the longitudinal direction from one end portion in the width direction (one end surface = a surface orthogonal to the width direction) (see FIG. 3).

  For convenience of explanation, the direction connecting the openings 1A and 1B of the core unit 1 is the longitudinal direction of the core unit 1, the one direction orthogonal to the longitudinal direction is the width direction, The direction perpendicular to the longitudinal direction and perpendicular to the width direction is defined as the thickness direction (see FIG. 1).

  Moreover, when the said coupling body 3 is formed, each coil 11 provided in each said core unit 1 is comprised so that it may connect in parallel (refer FIG. 4).

  The said connection body 3 is demonstrated in detail.

  FIG. 7 is a diagram illustrating a case where the core units 1 are joined to each other, and FIG. 8 is a diagram illustrating a case where the core units 1 that are joined to each other are separated.

  When the core units 1 are joined to each other, the joining is performed in the order shown in FIGS. 7A and 7B, and when the core units 1 joined to each other are separated, FIG. Separation is performed in the order shown in FIG.

  An engaging portion 17 is formed at one end in the longitudinal direction of the core unit 1 (one end of the casing 7 of the core unit 1), and the other end in the longitudinal direction (the casing of the core unit 1). 7 is formed with an engaged portion 19 that engages with the engaging portion 17 (see FIGS. 1 and 5).

  As shown in FIGS. 7 and 8, the engaged portion 19 is formed in a state in which the posture and position of the core unit 1 where the engaged portion 19 is formed are kept substantially constant. The engaging portions are kept in a substantially constant posture (while keeping the posture of each core unit 1 so that the longitudinal axial directions of the core units 1 are substantially matched). The engaged unit 19 and the engaging unit are moved relatively linearly relative to the core unit 1 on which the engaged unit 19 is formed. 17 are engaged with or separated from each other.

  Further, when the engaging portion 17 and the engaged portion 19 are engaged with each other, the core units 1 are joined to each other, and one core unit 1 is formed around an axis extending in the width direction. On the other hand, the other core unit 1 is configured to be rotatable by a predetermined angle.

  As described above, the core units 1 are joined to each other so that the wiring CB passes inside to form a connecting body 3 to detect a current flowing through the wiring CB (see FIG. 2).

  Further, when the core unit 1 is rotated at the joint portion, the loss prevention mechanism 21 that prevents the one core unit 1 and the other core unit 1 from being disconnected from each other, and the loss prevention mechanism 21 A release mechanism 23 for releasing the operation is provided in the core unit 1.

  In the core unit 1 shown in FIG. 1, the engagement portion 17 is formed on one end side of the housing 7 and the engaged portion 19 is formed on the other end side. The core unit having the engaged portions 19 formed at both ends and the core units having the engaging portions 17 formed at both ends are alternately connected so that the coupling body 3 is formed. May be.

  Here, the engaging portion 17, the engaged portion 19, the loss prevention mechanism 21, and the release mechanism 23 will be described in more detail.

  First, the housing 7 will be described.

  As shown in FIG. 5, the housing 7 includes a main body portion 25 and a cover member 27. Further, the main body portion 25 is constituted by a base portion 29 having a “U” -shaped cross section in a plane perpendicular to the longitudinal direction, and a flat lid portion 31 detachably attached to the base portion 29. ing.

  The engaged portion 19 is formed by a shallow concave portion 33 formed in a “U” shape. More specifically, on the other end portion side in the longitudinal direction of the base portion 29, there is a plate-like wall portion (wall) 35 provided with planes that are parallel to each other and extend in the longitudinal direction and the thickness direction. Is formed. And the said recessed part 33 is formed inside each said plate-shaped wall part 35. As shown in FIG.

  The engaging portion 17 is formed by a short protrusion 37 formed in a columnar shape. More specifically, a plate-like wall portion (wall) 39 having flat surfaces extending in the longitudinal direction and the thickness direction is formed on one end portion side in the longitudinal direction of the base portion 29. Has been. And the said protrusion 37 is formed in the outer side of each said plate-shaped wall part 39. As shown in FIG.

  In the width direction, the interval between the walls 35 is substantially equal to or slightly larger than the dimension between the outer surfaces of the walls 39, and when the core units 1 are joined to each other. Each wall 39 can enter inside each wall 35.

  The loss prevention mechanism 21 and the release mechanism 23 include a locked portion support portion 41, a locked portion (for example, a protrusion) 43, and a locking portion (for example, a through hole) 45.

  The locked portion support portion 41 is provided on the distal end side of the cover member 27. The cover member 27 has a base end portion engaged with the housing 7 (main body portion 25; lid portion 31) and is rotatable with respect to the housing 7.

  The locked portion 43 is provided in the locked portion support portion 41, and the locking portion 45 is provided in the housing 7 (main body portion 25; base portion 29).

  When the cover member 27 rotates, the locked portion support portion 41 enters the concave portion 33 formed in the “U” shape and forms the engaged portion 19 in a circular shape. (See FIG. 7B), the locked portion 43 is formed when the U-shaped engaged portion 19 is formed in a circular shape by the locked portion support portion 41. The cover member 27 is fixed to the housing 7 (main body portion 25; base portion 29) by engaging with a locking portion 45.

  Furthermore, the U-shaped engaged portion 19 opens in one direction in the thickness direction, and when one core unit 1 is joined to the other core unit 1, the other core unit 1 is joined. The position of the other core unit 1 with respect to the unit 1 (the position in the longitudinal direction and the width direction) is appropriately aligned, and in this aligned state, the other core unit 1 is connected to the one core unit 1. It moves relatively linearly in the thickness direction, engages the engaging portion 17 with the engaged portion 19, rotates the cover member 27, and engages the locked portion of the cover member 27. What is necessary is just to engage 43 and the latching | locking part 45 of the said housing | casing 7. FIG. Further, when the other core unit 1 is separated from one core unit 1, an operation in the reverse procedure to the above-described operation may be performed.

  By doing in this way, in connection body 3 which connected a plurality of core units 1 in the longitudinal direction, problems, such as easy connection between core units, can be solved effectively.

  More specifically, when the current detection operation is completed by surrounding the wiring CB by making the connecting body 3 of the current transformer for measuring instrument annular, one of the joints between the core units is disconnected. The connection body 3 can be removed from the wiring CB by the operator (operator) pulling with one end of the unbonded connection, but a large number of wirings are usually gathered around the wiring CB in the wall or in a narrow switchboard. In general, there is no space for taking out work with a margin.

  Furthermore, the connection body 3 that has been released from the annular shape has a “U” shape. If one end is pulled in this state, a large force is applied to the joint portion between the core units, and the joint portion is easily detached unless the configuration described in the present application is used.

  In the case of a current transformer for a measuring instrument having a configuration in which a plurality of core units are joined to form a connector 3 as in the invention of the present application, it is sufficient if there is only one disjoined joint portion. The workability is significantly hindered, such as having to pick up the scattered core units even in a narrow work space.

  Also, when scattered, the core unit core and terminal fittings are damaged by hitting something, making it impossible to rejoin or even if rejoining is possible, the electrical connection state deteriorates and is high A fatal problem may occur as a current transformer for a measuring instrument in which measurement accuracy cannot be maintained.

  On the other hand, by adopting a configuration like the embodiment described in the present application, while achieving reliable and simple joining, it has a high level of mutually contradicting effects that it is not easily detached by an operation at the time of work. It is possible to achieve both.

  By the way, you may change the said engaging part 17, the to-be-engaged part 19, the said anti-slipping mechanism 21, and the said release mechanism 23 as follows.

  FIG. 9A is a front view showing a modified example of the engaging portion 17, the engaged portion 19, the loss prevention mechanism 21, and the release mechanism 23, and FIG. 9B is a plan view of FIG. 9A. FIG.

  In FIG. 9, the engaged portion corresponding to the engaged portion 19 is formed by a circular through hole 33a provided in the housing of the core unit on one end side in the longitudinal direction, and the engagement The engaging portion corresponding to the portion 17 is formed by a circular short projection 37a provided on the housing of the core unit on the other end portion side in the longitudinal direction. Then, the projections 37a are engaged with the through holes 33a to join the core units.

  Further, the loss prevention mechanism 21 and the release mechanism 23 include a connecting portion 47 that connects the protrusion 37a and the main body of the housing of the core unit. And when the said core units 1 are attached or detached, the said connection part 47 is comprised so that it may elastically deform. A guide portion 49 is provided adjacent to the through hole 33a so that the protrusion 37a can easily enter the through hole 33a.

  FIG. 10 is a front view showing a modified example of the engaging portion 17, the engaged portion 19, the loss prevention mechanism 21, and the release mechanism 23, and FIG. 10A is a view before joining the core units. FIG. 10B shows a state in which the core units are joined to each other.

  In FIG. 10, the engaging portions corresponding to the engaging portions 17 are protrusions provided on the casing of the core unit on one end side in the longitudinal direction, and are opposed to each other in a parallel state. It is formed by a short protrusion 51 formed in a cross-sectional shape surrounded by a straight line portion and arcuate portions facing each other.

  The engaged portion corresponding to the engaged portion 19 has a shallow concave portion 53 formed in a circular shape and a width shorter than the diameter of the circular concave portion 53 adjacent to the circular concave portion 53. It is formed in a substantially “U” shape by the provided shallow concave portion 55 formed in a rectangular shape.

  The width B1 between the linear portions of the engaging portion is formed to be substantially the same as the width B3 of the rectangular portion of the engaged portion, and the radius R1 of the arc-shaped portion of the engaging portion is The radius R3 of the circular portion of the engaged portion is substantially equal.

  The loss prevention mechanism 21 is provided with a stopper 57, and the engagement portion (the engagement portion ( The protrusion 51) is engaged with the circular recess 53, and after this engagement, the housing provided with the engaging portion is rotated relative to the housing provided with the engaged portion. Thereafter, the stopper 57 is operated so as not to reach the rotation angle before the rotation. And the said to-be-engaged part and the said engaging part are comprised so that it may be hard to remove | deviate.

  The release mechanism 23 is operated by releasing the operation of the stopper 57, and the engagement portion is disengaged from the engaged portion.

  In addition, the said protrusion 51 and the said recessed parts 53 and 55 are provided in the both ends part side of the width direction of a core unit similarly to the case where it shows in FIG.

  By the way, as already understood, the cover member 27 is rotatable in the vicinity of a portion of the housing 7 where the engaged portion 19 is formed.

  Each core unit 1 is joined in the longitudinal direction of the other core unit 1 and the one core joined to the other core unit 1 with the cover member 27 of the other core unit 1 opened. With the longitudinal direction of the unit 1 being parallel to each other, the engaging portion 17 of the one core unit 1 is passed through the opening of the cover member 27 of the other core unit 1, and the engaging portion 17 and the This is done by engaging the engaged portions 19 with each other.

  After this engagement, when the other core unit 1 and the one core unit 1 joined to the other core unit 1 are linear, the cover member 27 is rotated to rotate the covered member. By locking the locking portion 43 to the locking portion 45, the anti-slipping mechanism 21 operates. On the other hand, by opening the cover member 27 as shown in FIG. 8C, for example, the release mechanism 23 is operated, and the loss prevention mechanism 21 is released.

  Here, the form of the cover member 27 when each core unit 1 is joined will be described.

  FIG. 11 is a diagram showing a cross section of XIA-XIB in FIG.

  First, in a state where the core units 1 are still joined, the outer surface of the cover member 27 exists on substantially the same plane as the outer surface of the casing 7 of each core unit 1 that is linear. Thus, the tip of the cover member 27 is substantially hidden (see FIGS. 7B and 8A).

  On the other hand, when one core unit 1 is rotated by a predetermined angle with respect to the other core unit 1 from the straight state, the tip end portion 27A of the cover member 27 appears. (See FIG. 8B and FIG. 11).

  Further, as shown in FIG. 12 (a diagram showing a stopper 59 for restricting the rotation angle of the core unit), the other core unit 1 and one of the other core units 1 joined to the core unit 1 are connected to the core unit 1. A rotation angle limiting stopper 59 for limiting the rotation angle between the core unit 1 and the core unit 1 is provided.

  The stopper 59 is a linear portion formed on the outer surface of the casing 7 of each core unit 1 (the outer surface provided at the end in the longitudinal direction) (at both ends of the casing 7 in the width direction). The core unit 1 is operated by contacting the parts 61 extending in the thickness direction with each other, and the end of the linear part 61 constituting the stopper 59 (of the core unit 1). A chamfer 63 is formed at the end in the thickness direction.

  Then, as shown in FIG. 12A, when the core units 1 joined to each other extend linearly, a triangular portion A1 as shown by the oblique lines in FIG. Etc. are difficult to be pinched. Also, as shown in FIG. 12B, when one of the core units joined to each other is rotated, a triangular portion A3 as shown by the oblique lines in FIG. It is hard to be pinched.

  In addition, the rotation angle of each core unit 1 joined mutually changes, for example between the state shown to Fig.12 (a), and the state shown in FIG.12 (b). That is, from the state in which each core unit 1 is linear in the longitudinal direction, the other core unit 1 is unidirectional with respect to one core unit 1 by a predetermined angle (for example, 60 °). It is designed to rotate.

  In particular, the rotation of the core units 1 joined to each other is affected by the stopper 59 that operates by bringing the linear portions 61 into contact with each other, and does not rotate in the direction opposite to the one direction. It is like that.

  The direction opposite to the one direction will be described in detail with reference to the drawings. In FIGS. 12 (a) to 12 (b), the right core unit 1 is rotated, for example, by 60 ° in the clockwise direction (one direction). However, the direction opposite to the one direction in this state refers to the counterclockwise direction of the right core unit 1 from the linear joining state of the core units.

  Therefore, the current transformer 5 for measuring instrument using the coupling body 3 of the present invention is used in the annular or circular shape shown in FIG. 2, and a part thereof is recessed toward the center of the annular shape. Or to be deformed into a bowl shape instead of an annular shape.

  When an annular or saddle-shaped current transformer (connector) having such a dent is formed, the balance of the influence of the leakage magnetic flux from the primary current flowing in each wiring CB is partially remarkably different in each core unit 1. As a result, residual current may be generated, resulting in a decrease in measurement accuracy.

  Next, the terminal metal fitting 65 will be described.

FIG. 13 is a view showing a schematic configuration of the terminal fitting 65. FIG. 14 is a view showing a XIVA-XIVB cross section in FIGS. 13 (a) and 13 (b).

  Inside the casing 7 of the core unit 1, a strip-shaped terminal fitting for connecting the coils 11 provided in the core units 1 in parallel when the connecting body 3 is formed. 65 is provided.

  The terminal fitting 65 is generated, for example, by punching a thin metal flat plate material and subjecting the punched material to pressing or bending.

  The end of the terminal fitting 65 on the engaged portion 19 side of the core unit 1 in a state in which the terminal fitting 65 is installed on the core unit 1 is bent and folded as shown in FIG. In this double plate-like portion, a circular recess 67 is provided to face the double plate-like portion.

  On the other hand, the end of the terminal fitting 65 on the engaging portion 17 side of the core unit 1 in a state where the terminal fitting 65 is installed on the core unit 1 is bent as shown in FIG. It has a double plate shape, and circular projections 69 are provided opposite to the double plate portion.

  When the core units 1 are joined to each other, as shown in FIG. 14B, the center of the recess 67 and the center of the protrusion 69 are engaged with each other (the protrusion 69 of the recess 67 is sandwiched). The center of rotation of the joint portion of each core unit 1 and the center of the recess 67 or the protrusion 69 coincide with each other.

  Further, the terminal fitting 65 on which the projection 69 is formed is sandwiched between the terminal fitting 65 on which the depression 67 is formed, and the depression 67 and the projection 69 come into contact with each other with an urging force. Yes.

  A protrusion 69 is provided at the end of the terminal fitting 65 on the engaged portion 19 side of the core unit 1, and a recess 67 is provided at the end of the terminal fitting 65 on the engaging portion 17 side of the core unit 1. May be.

  Further, as shown in FIGS. 14C and 14D, a circular through hole 71 may be provided instead of the recess 67.

  Further, as shown in FIGS. 1 and 5, one core unit 1 of the core units 1 joined to each other is rotated with respect to the other core unit 1. A cover portion (cover member; first cover portion) 27 for preventing the iron core 9, the coil 11, the terminal fitting 65, and the terminal portion 73 (see FIG. 6) of the coil from being exposed. A cover part (second cover part) 75 is provided.

  The cover member 27 is on one end side (one surface) in the thickness direction of the core unit 1 and is rotated by the predetermined angle (one core unit 1 is predetermined with respect to the other core unit 1). Is provided on the other end side of the core unit 1 (one end side of the lid portion 31), and the cover portion 75 is The lid 31 is provided integrally with the lid 31 on the other end side.

  As shown in FIG. 7B and FIG. 11, when the core units 1 are joined (connected) to each other, at least a part of the cover member 27 and at least a part of the cover part 75 are attached to the core unit 1. In a state where the core units 1 that are overlapped with each other in the thickness direction and are joined to each other are linear, the overlapping portions of the cover members 27 and the cover portions 75 are formed large, and the core unit 1 Is configured so that the overlapping portions of the cover members 27 and the cover portions 75 become smaller as the rotation of the cover portion (as the joint portion of the core unit 1 joined as described above becomes convex). Has been.

  As described above, the cover member (first cover portion) 27 is separated from the main body portion 25 (lid portion 31) of the housing 7 and is configured in a plate shape as a separate member. It is provided so as to be rotatable with respect to the main body portion 25 (lid portion 31) of the casing 7 on the side, and in a state where the cover member 27 is closed, on one surface in the thickness direction of the casing 7 The surface on which the cover member 27 is provided and the cover member 27 are substantially in the same plane. When the cover member 27 is open, the longitudinal direction of the casing 7 An opening 77 is formed on the other end side (one side of the end portion) and on the convex side in the thickness direction (the side that becomes convex when the joint portion of the core unit 1 rotates by a predetermined angle) (see FIG. (Refer FIG. 7, FIG.8 (c)).

  On the distal end portion 27A side of the cover member 27, a locked portion 43 that engages with a locking portion 45 formed on the main body portion 25 (base portion 29) of the casing 7 is formed. The cover member 27 is integrated with the body portion 25 of the housing 7 in a state where the lid portion 31 of the base portion 29 is installed and the locking portion 45 and the locked portion 43 are engaged with each other. It is supposed to be combined.

  Here, the coupling between the cover member 27 and the main body 25 (base 29) will be described in detail.

  FIG. 15A is a view showing a state in which the cover member 27 and the main body portion 25 are coupled to each other, and is a view showing a cross section taken along the line XVA-XVB in FIG. FIG. 15B and FIG. 15C are diagrams showing a modification of the connecting portion between the cover member 27 and the main body 25.

  As described above, the protrusion 43 that slightly protrudes outward in the width direction at both ends in the width direction of the cover member 27 to form the locked portion is formed on the front end portion side of the cover member 27. It is provided via the locked portion support portion 41 (see FIG. 5).

  And as shown to Fig.15 (a), in the state which the said cover member 27 closed, the said to-be-latched part support part 41 and the said to-be-latched part 43 will be inside the said housing | casing 7 (base part 29). A recess (for example, the protrusion 43 forming the locked portion is formed on the walls 35 at both end portions in the width direction of the housing 7 (base portion 29) and forms the locking portion (for example, The cover member 27 is integrally coupled to the housing 7 through the through hole 45).

  The protrusion 43 is chamfered (not shown), so that the protrusion 43 can be easily engaged with the recess 45.

  By the way, as shown in FIG. 15 (b), the locked portion is formed on the front end portion side of the cover member 27 so as to slightly protrude inward in the width direction at both end portions in the width direction of the cover member 27. When the cover member 27 is closed, the locked portion support portion 41 and the locked portion protrusion 79 are connected to the casing. The projection 7 constituting the locked portion is formed on the walls 35 at both ends in the width direction of the casing 7 so as to form the locking portion. The cover member 27 may be integrally coupled to the housing 7 by entering the recessed portion (for example, through hole) 45.

  Further, as shown in FIG. 15C, the locked portion is formed on the front end portion side of the cover member 27 so as to slightly protrude inward in the width direction at both end portions in the width direction of the cover member 27. The protrusion 79 is provided via the locked portion support portion 41, and is slightly separated from the locked portion support portion 41, and a clamping portion 81 is provided on the inner side in the width direction of the cover member 27. In a state in which the member 27 is closed, the locked portion support portion 41 sandwiches the housing 7 outside the housing 7, and the protrusion 79 constituting the locked portion has the housing 7. The cover member 27 is integrated with the housing 7 so as to enter the hole 45 formed in the walls 35 at both end portions in the width direction of the wall and forming the locking portion. The wall 3 at both ends in the width direction of the housing 7 is formed by the locked portion support portion 41 and the clamping portion 81. It may be sandwiched a.

  Further, in the structure shown in FIG. 15 (c), the protrusion 79 may be provided in the clamping portion 81 instead of being provided in the locked portion support portion 41.

  In the core unit 1, as described above, the cover member 27 is rotatably engaged with the lid portion 31 on the other end side in the longitudinal direction of the lid portion 31.

  On the other hand, a cover portion (second cover portion) 75 formed in an arc shape so that the tip end portion is bent inward in the thickness direction is integrally formed on the other end portion side in the longitudinal direction of the lid portion 31. (See FIGS. 1, 5, and 7B).

  And as already understood, in the state where the lid portion 31 is installed on the base portion 29, a cross section of the casing 7 is formed in a "B" shape in the middle portion in the longitudinal direction, In the portion where the cover portion 75 is present, the cross section of the housing 7 is formed in a “U” shape, and in the portion where the cover member 27 is present in a state where the cover member 27 is closed, The cross section of the casing is formed in a “U” shape, and when the core units 1 are joined to each other, the cover member 27 covers the cover portion 75 in the thickness direction (FIG. 7 ( b)).

  Further, the core unit 1 has the housing 7 when the engaging portion 45 of the main body portion 25 (base portion 29) of the housing 7 and the engaged portion 43 of the cover member 27 are engaged with each other. A spread prevention mechanism 83 is provided to prevent the main body portion 25 from spreading too much in the width direction.

  Here, the spread preventing mechanism 83 and the like will be described.

  FIG. 16B is a perspective view showing an overview of the core unit 1 as in FIG. FIG. 1 shows a state in which the cover member 27 is closed, but FIG. 16B shows a state in which the cover member 27 is slightly opened.

  FIG. 16A is a diagram showing a state in the middle of assembling the lid portion 31 with the cover member 27 assembled to the base portion 29.

  FIG. 17 is a diagram showing a cross section XVIIA-XVIIB in FIG.

  The assembly of the lid portion 31 and the base portion 29 is present at both ends in the width direction of the base portion 29 while elastically deforming so that the opening side of the “U” -shaped base portion 29 is slightly widened in the width direction. The projections 87 projecting on both sides in the width direction of the lid 31 are engaged with the recesses 85 provided on the walls.

  The spread preventing mechanism 83 includes a protrusion 89 provided on each end in the width direction of the base portion 29 and a recess (for example, a through hole) provided on the lid portion 31 and engaged with the protrusion 89 of the base portion 29. 91).

  Further, as shown in FIG. 16, in order to make it easy to assemble the lid portion 31 to the base portion 29, the projection 89 and the concave portion 91 constituting the spread prevention mechanism 83, and the lid portion 31 are attached to the base portion 29. A distance L1 between the protrusion 87 of the lid portion 31 and the recess portion 85 of the base portion 29 provided for assembly is large.

  Next, the engaging portion between the lid portion 31 and the cover member 27 will be described in detail.

  FIG. 18 is a view for explaining an engaging portion between the lid portion 31 and the cover member 27, and is a view showing a cross-section XVIII in FIG.

  18A shows a state before the cover member 27 is assembled to the lid portion 31, and FIG. 18B shows a state immediately after the cover member 27 is assembled to the lid portion 31, and FIG. c) is a diagram illustrating a state in which the cover member 27 is rotated after the cover member 27 is assembled to the lid portion 31.

  On the base end side of the cover member 27, a slit 93 extending in the width direction and a cylindrical portion 95 extending in the width direction are provided.

  When the lid portion 31 and the cover member 27 are assembled to each other at one end side (one side of the end portion) of the body portion 25 of the housing 7 that engages with the cover member 27, the cylindrical portion A central shaft portion 97 that extends into the central portion of 95 is provided to extend in the width direction, and a notch 99 for allowing a part of the cylindrical portion 95 to enter when the cover member 27 rotates is provided. Adjacent to the central shaft portion 97 is provided long in parallel with the central shaft portion 97.

  The width W1 of the slit 93 is slightly smaller than the outer diameter D1 of the central shaft portion 97, and the lid portion 31 is in a state where the lid portion 31 and the cover member 27 exist on one plane. When the cover member 27 and the cover member 27 are assembled close to each other, the cylindrical portion 95 is elastically deformed, the slit 93 is slightly expanded, and the central shaft portion 97 enters the inside of the cylindrical portion 95, and the lid portion 31. The cover member 27 is assembled to the above.

  Further, even when the lid portion 31 and the cover member 27 are on substantially one plane (a state in which the cover member 27 is closed), the locking portion 45 of the main body portion 25 of the housing 7. And the locked portion 43 of the cover member 27 are engaged with each other, so that the cover member 27 is not detached from the lid portion 31.

  Moreover, as shown in FIG. 1, FIG. 5, FIG. 8 (f), one end side (one surface) in the thickness direction and the side (inside) that becomes the concave side when the core unit 1 rotates. Is provided with an elastic inner cover (cover made of a plate-like rubber) 101 for preventing a gap due to the rotation of the core unit 1 between the core units 1 joined to each other. ing.

  The inner cover 101 is on the other end side in the longitudinal direction of the core unit (the side on which the engaged portion 19 is formed) and on one end side in the thickness direction (the side opposite to the cover member 27). ) Extending in the longitudinal direction and the width direction.

  Then, the inner cover 101 forms a “U” -shaped cross-sectional portion (the portion of the housing 7) where the cover member 27 is provided, and the core unit 1 is joined. A portion of the casing of the other core unit 1 thus formed (a portion having a “U” -shaped cross section in which the cover portion 75 is formed) has a “B” shape.

  Next, the core unit 1 itself will be described in more detail.

  FIG. 19 is a diagram showing a state when the coil units 103 provided inside the core unit 1 are joined to each other. The coil units 103 are automatically joined to each other when the core units 1 are joined.

  Moreover, Fig.19 (a) shows the state before joining the coil units 103, FIG.19 (b) shows the state in the middle of joining the coil units 103, FIG.19 (c) is shown. The state which joined the coil units 103 is shown.

  An overview of the coil unit 103 alone is also shown in FIG.

  20 is a view taken in the direction of arrow XX in FIG. 6 and shows a state where the terminal fitting 65 is assembled to the coil unit 103. FIG. 21 shows a state before the terminal fitting 65 is assembled to the coil unit 103. FIG.

  A space is formed in the housing 7 of the core unit 1 as already understood.

  A coil unit 103 including an iron core 9 and a coil 11 wound around the iron core 9 is installed inside the housing 7.

  Further, as described above, the casing 7 is formed by being divided into the base portion 29 and the lid portion 31, and the posture of the coil unit 103 is maintained in a state in which the posture and position of the base portion 29 are kept substantially constant. Similarly, the coil unit 103 can be installed inside the base 29 by moving the coil unit 103 linearly relative to the base 29 while maintaining substantially constant.

  After the coil unit 103 is installed, for example, the lid 31 is relatively linear with respect to the base 29 in substantially the same direction as the coil unit 103 while keeping the attitude of the lid 31 substantially constant. By moving, the lid portion 31 is integrally installed on the base portion 29, so that the base portion 29, the coil unit 103, and the lid portion 31 are integrally assembled.

  More specifically, as described above, the core unit 1 is a terminal for electrically connecting the coils 11 of the core units 1 to each other when the core units 1 are coupled (joined) to each other. A metal fitting 65 is provided.

  Then, with the posture and position of the coil unit 103 kept substantially constant, the terminal fitting 65 is moved relative to the coil unit 103 while keeping the posture of the terminal fitting 65 similarly substantially constant. By moving linearly, the terminal fitting 65 can be installed on the coil unit 103, and the coil unit 103 and the terminal fitting 65 can be installed on the base 29 after the installation. ing.

  In this way, the terminal unit 65 and the coil unit 103 are installed on the base 29, and the lid 31 is fixedly installed on the base 29, whereby the core unit 1 is assembled.

  It should be noted that the terminal fitting 65 is relatively linear with respect to the base 29 while the posture of the terminal fitting 65 is kept substantially constant in a state where the posture and position of the base 29 are kept substantially constant. The terminal fitting 65 may be installed on the base 29 by moving to, and the coil unit 103 may be installed on the base 29 after the installation. In other words, the terminal fitting 65 may be installed on the base 29 first, not the coil unit 103 first.

  Incidentally, the coil unit 103 is provided with a positioning portion 105 for positioning the terminal fitting 65 (see FIG. 6). In addition, when the coil unit 103 having the terminal fitting 65 attached thereto is inserted into the base 29 from the opening in the thickness direction of the base 29 toward the inside of the base 29, A positioning portion 107 for positioning the coil unit 103 with respect to the base portion 29 is provided (see FIG. 5).

  Then, as described above, the base 31, the coil unit 103, and the terminal fitting 65 are installed by installing the lid 31 on the base 29 where the terminal fitting 65 and the coil unit 103 are positioned. And the lid portion 31 are assembled together.

  The base 29 is provided with a first positioning portion for positioning the terminal fitting 65 inserted in the inner direction of the base 29 from the opening in the thickness direction of the base 29 with respect to the base 29. A second positioning portion for positioning the coil unit 103 inserted in the inner direction of the base portion 29 from the opening portion in the thickness direction of the base portion 29 with respect to the base portion 29; By installing the terminal fitting 65 and the coil unit 103 on the base 29 where the positioning is positioned, the base 29, the terminal fitting 65, the coil unit 103, and the lid 31 are assembled together. It may be.

  Here, the positioning portions 105 and 107 will be described in detail.

  As shown in FIG. 6, the coil unit 103 includes a rectangular cylindrical main body 109 made of an insulator. At both ends of the main body 109, rectangular ridges 111 and 113 are provided.

  A coil 11 is wound around the outer periphery of the main body 109 and between the flanges 111 and 113.

  Two terminal portions 73 of the coil 11 are provided apart from each other at a portion outside the flange 111. In addition, the flanges 111 and 113 are provided with slits 115, and an intermediate portion of the plate-like long terminal fitting 65 enters the slit 115 to position the terminal fitting 65 with respect to the coil unit 103. It is like that.

  Note that two terminal fittings 65 are installed in the coil unit in response to the presence of the two terminal portions 73.

  The terminal fittings 65 are formed symmetrically with respect to one plane, and the terminal fittings 65 are positioned and installed on the coil unit 103 in each terminal fitting 65. Sometimes, a contact portion 117 that is in electrical contact with the terminal portion 73 is provided. The contact portion 117 is formed by, for example, bending the material when the terminal fitting 65 is generated.

  Further, the base 29 is provided with an engaged portion 121 that engages with an outer peripheral portion (a U-shaped outer peripheral portion; see FIG. 20) 119 of each of the flanges 111 and 113 and a portion in the vicinity of the outer peripheral portion 119. The base portion 29 is positioned with respect to the coil unit 103 by engaging the outer peripheral portion 119 and a portion in the vicinity of the outer peripheral portion 119 with the engaged portion 121. .

  As shown in FIGS. 6 and 19, an iron core 9 is provided inside the cylindrical main body 109. The iron core 9 is configured by laminating thin plate-like members. On both ends of the main body 109, the iron cores 9 are laminated every other sheet, and have a so-called comb shape (see, for example, FIG. 9B).

  When the core units 1 are joined to each other, as shown in FIG. 19, the comb-like ends of the other iron cores 9 enter the comb-like ends of the iron cores 9, and the iron cores 9 are joined to each other. At the same time, the terminal fittings 65 are also connected to each other (see also FIGS. 13 and 14).

  In addition, as a member which comprises the iron core 9, you may use metals and alloys other than iron provided with magnetism.

  As shown in FIG. 2, the core units 1 configured in this way are connected appropriately in accordance with the form of the wiring CB, and when forming the connecting body 3 in an annular shape, if the wiring CB is surrounded, The leakage of the wiring CB can be checked.

  According to the zero-phase current transformer 5, the connecting body 3 is formed by joining the core unit 1 in which the iron core 9 and the coil 11 are provided in the housing 7 to each other. Is easy to attach and detach, and the joint between the core units 1 is rotatable, so that the configuration of the connecting body 3 can be easily changed in accordance with the configuration of the wiring CB, and the current flowing through the wiring CB Can be measured accurately, and the risk of damaging the coil 11 and the like installed inside the connector 3 can be avoided.

  Further, according to the zero-phase current transformer 5, since the coils 11 are connected in parallel, even if the number of connected core units 1 is increased or decreased, the characteristics of the coupling body 3 (when detecting the current of the wiring) The characteristic of () of FIG. 4 is hardly changed, and the current flowing through the wiring CB can be accurately measured.

  Further, according to the zero-phase current transformer 5, when the core units 1 joined to each other are linear, the tip 27A of the cover member 27 is configured to be substantially hidden. The outer surface of the connection body 3 can be made into a smooth shape at the time of use of 3, and it becomes easy to install the connection body 3. On the other hand, when the core units 1 joined to each other are rotated from the linear state, the distal end portion 27A of the cover member 27 appears so that the core units 1 joined to each other are It becomes easy to separate.

  Moreover, according to the zero-phase current transformer 5, since the chamfer 63 is formed at the end of the linear portion 61 constituting the stopper 59, each connected core unit 1 is rotated. In addition, there is no risk of a finger or the like being pinched between the core units 1.

  Furthermore, according to the zero-phase current transformer 5, the terminal fittings 65 are joined to each other by engaging the circular protrusion 69 and the circular recess 67. It becomes easy to make surface contact, and it becomes easy to rotate the connecting portion, and wear of the connecting portion when rotating can be suppressed.

  Further, when the core unit 1 rotates about an axis extending in the width direction of the core unit 1 and the connecting body 3 surrounds the wiring CB by this rotation, the signal line 15 is connected to the core unit 1. 1 extends in the longitudinal direction of the core unit 1 (longitudinal direction of the coupling body 3) from the end surface of the wiring CB in the extending direction of the signal line 1, so that the signal line 15 is not obstructive when measuring the current of the wiring CB .

  In the width direction, the distance between the walls 35 (distance between the inner surfaces) is substantially equal to or slightly larger than the dimension between the outer surfaces of the walls 39. Even if the connecting units 3 are installed by connecting the core units 1 to each other in order to measure the current flowing through the wiring CB extending in a direction intersecting with the vertical direction at a small angle, the joining of the core units 1 is performed. The part is difficult to bend in the width direction of the core unit 1.

  Moreover, according to the zero-phase current transformer 5, the connection body 3 is formed by mutually joining the core unit 1 in which the iron core 9 and the coil 11 are provided, and the core units 1 are attached to and detached from each other. It is easy and the joint between the core units 1 is rotatable, and when one of the core units 1 joined to each other rotates relative to the other core unit 1 The cover member 27 and the cover portion 75 for preventing the iron core 9, the coil 11, and the terminal portion 73 and the terminal fitting 65 of the coil 11 from being exposed are provided in accordance with the form of the wiring CB. Thus, the form of the connection body 3 can be easily changed, the current flowing through the wiring CB can be accurately measured, and the risk of damaging the coil 11 and the like inside the connection body 3 can be avoided. With wear, even at the junction of the core unit 1 easily removable and pivoting, can be protected wiring or the like of the core unit 1 (coil 11, the core 9, the terminal unit 73, the terminal fitting 65).

  Further, according to the zero-phase current transformer 5, when the locked portion 43 of the cover member 27 is engaged with the locking portion 45 of the main body portion 25, the main body portion 25 of the housing 7 is too wide in the width direction. Since the spread prevention mechanism 83 for preventing this is provided, it is possible to prevent deformation and breakage of the main body portion 25 of the casing 7 due to excessive spread.

  Further, according to the zero-phase current transformer 5, when the cover member 27 is assembled to the lid portion 31, the central shaft portion 97 of the lid portion 31 is passed through the slit 93 of the cover member 27, and the cylindrical shape of the cover member 27. Since it suffices if it is inserted into the portion 95, the cover member 27 can be easily assembled to the lid portion 31.

  Furthermore, according to the zero-phase current transformer 5, since the inner cover 101 is provided, the joint portion of each core unit 1 can be reliably covered.

  According to the core unit 1, since the assembly is performed by linearly moving while keeping the posture of each member constituting the core unit 1 substantially constant, the assembly of the core unit 1 itself becomes easy. And it becomes easy to automate the assembly using a robot or the like.

  In the above-described embodiment, the zero-phase current transformer has been described as an example. However, not only the zero-phase current transformer but also a current transformer for a measuring instrument such as a clamp meter that can detect a current flowing through the wiring. Also, the one according to the above embodiment can be applied.

It is a perspective view which shows the external appearance of the core unit which comprises the connection body of the current transformer for measuring devices which concerns on embodiment of this invention. It is a perspective view which shows the general appearance of the coupling body comprised by the said core unit. (A) is the IIIA arrow directional view in FIG. 2, (b) is the IIIB arrow directional view in FIG. It is a circuit diagram of a current transformer for a measuring instrument (zero phase current transformer). It is a perspective view which shows the external appearance of the housing | casing which comprises the core unit. It is a perspective view which shows the external appearance of the iron core and coil which are provided in the inside of a housing | casing. It is a figure explaining the case where each core unit is joined mutually. It is a figure explaining the case where each core unit joined mutually is separated. (A) is a front view which shows the modification of an engaging part, a to-be-engaged part, a loss prevention mechanism, and a cancellation | release mechanism, (b) is a top view of Fig.9 (a). It is a front view which shows the modification of an engaging part, a to-be-engaged part, a loss prevention mechanism, and the said cancellation | release mechanism. It is a figure which shows the XIA-XIB cross section in FIG.8 (b). It is a figure which shows the stopper which controls the rotation angle of a core unit. It is a figure which shows schematic structure of a terminal metal fitting. It is a figure which shows the XIVA-XIVB cross section in Fig.13 (a), (b). (A) is a figure which shows the state which couple | bonded the said cover member and the main-body part mutually, and is a figure which shows the XVA-XVB cross section in FIG.7 (b). (B), (c) is a figure which shows the modification of the coupling | bond part of the said cover member and a main-body part. (A) is a figure which shows the state in the middle of assembling | attaching the cover part in which the cover member was assembled | attached to a base, (b) is a perspective view which shows the external appearance of a core unit similarly to FIG. It is a figure which shows the XVIIA-XVIIB cross section in FIG.16 (b). It is a figure explaining the engaging part of a cover part and the said cover member, and is a figure which shows the XVIIIA-XVIIIB cross section in FIG. It is a figure which shows a state when joining the coil units provided in the inside of a core unit. It is a XX arrow line view in Drawing 6, and is a figure showing the state where the terminal metal fitting was assembled to the coil unit. It is a figure which shows the state before attaching a terminal metal fitting to a coil unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Core unit 1A, 1B Opening part 3 Connection body 5 Zero phase current transformer 7 Case 9 Iron core 11 Coil 13 Insulation monitoring device 15 Signal line 17 Engagement part 19 Engagement part 21 Loss prevention mechanism 23 Release mechanism 25 Main unit (Body main unit)
27 Cover member (first cover part)
27A Front end 29 Base 31 Lid 33 Recess 35, 39 Wall 37 Protrusion 41 Locked portion support 43 Locked portion (protrusion)
45 Locking part (recess; through hole)
59 Rotation angle limiting stopper 61 Part 63 Chamfer 65 Terminal fitting 67 Dimple 69 Projection 73 Terminal part 75 Cover part (second cover part)
77 Opening 79 Protrusion 85 Recess 87, 89 Protrusion 91 Recess 93 Slit 95 Cylindrical part 97 Center shaft 101 Inner cover 103 Coil units 105, 107 Positioning part

Claims (9)

In the current transformer for measuring instrument capable of detecting the current flowing through the wiring in a state of being electrically non-contact with the wiring,
A plurality of core units each having a casing, an iron core provided inside the casing, and a coil wound around the iron core and provided inside the casing are configured to be joined to each other. With a connector,
The core unit is easily attached to and detached from the other core units and is rotatably engaged. When the core units are joined to each other to form the connection body, the connection body And is configured to be able to detect the current flowing through the wiring,
For preventing the core, the coil, and the terminal portion of the coil from being exposed when one of the core units joined to each other rotates with respect to the other core unit. A current transformer for a measuring instrument, wherein a cover is provided in the casing. In the current transformer for measuring instrument capable of detecting the current flowing through the wiring in a state of being electrically non-contact with the wiring,
A core unit having a rectangular and cylindrical casing having both ends opened, an iron core provided inside the casing, and a coil wound around the iron core and provided inside the casing Are connected to each other, and are connected to each other.
The width of the end of the core unit in the longitudinal direction, which is the direction connecting the openings of the core unit, is easily removable from the end of the other core unit and is perpendicular to the longitudinal direction. Are engaged with each other so as to be rotatable about a shaft extending in the direction. When the core units are joined to each other to form a connection body, the connection body surrounds the wiring and flows through the wiring. Configured to detect current,
The rotation angle of each core unit joined to each other is such that the other core unit rotates in one direction by a predetermined angle with respect to one core unit from a state in which each core unit is linear. It comes to move,
One surface of the thickness direction which is a direction perpendicular to the longitudinal direction and the width direction and on the side which becomes a convex side when rotated by the predetermined angle, The housing is provided with a first cover part, and the other core unit to be joined is provided with a second cover part,
In a state where the core units are joined to each other, at least a part of the first cover part and at least a part of the second cover part overlap each other,
In the state where the core units joined to each other are linear, the overlapping portions of the cover portions are formed larger, and as the rotation angle increases, the overlapping portions of the cover portions are increased. A current transformer for a measuring instrument which is configured to be small. The current transformer for a measuring instrument according to claim 2,
The first cover portion is separated from the main body portion of the housing and is configured in a plate shape, and is provided to be rotatable with respect to the main body portion of the housing on the base end side,
In a state where the first cover portion is closed, one surface in the thickness direction of the housing that is provided with the first cover portion is substantially the same as the first cover portion. In the state where the first cover portion is open, the opening portion is formed on one side of the longitudinal end portion of the housing and on the convex side in the thickness direction. Formed,
On the distal end side of the cover part, a locked part that engages with a locking part formed on the main body part of the housing is formed,
The first cover portion is integrally coupled to the main body portion of the housing in a state where the locking portion and the locked portion are engaged with each other. Current transformer for measuring instrument. The current transformer for a measuring instrument according to claim 3,
The portion of the housing where the first cover portion is installed is formed in a “U” shape in a cross section by a plane perpendicular to the longitudinal direction when the first cover portion is closed. And
Protrusions that slightly protrude in the width direction to form the locked portions are formed on both ends in the width direction of the first cover portion on the tip end side of the first cover portion. It is provided via the locking part support part,
In the state where the first cover portion is closed, the locked portion supporting portion and the locked portion enter the inside of the housing, and the protrusions constituting the locked portion are The first cover portion is integrally coupled to the main body portion of the housing, entering into the recesses formed on the walls at both ends in the width direction of the main body portion of the housing and forming the locking portion. Is supposed to be
The main body portion of the housing is configured by a base portion having a cross-sectional shape formed in a U shape in a plane perpendicular to the longitudinal direction and a flat lid portion, and the first cover portion includes the first cover portion, The lid is rotatably engaged with the lid on one side of the longitudinal end of the lid,
When the engaging portion of the main body portion of the casing is engaged with the locked portion of the first cover portion, the spread prevention for preventing the main body portion of the housing from spreading too much in the width direction. A current transformer for a measuring instrument, characterized in that a mechanism is provided. The current transformer for a measuring instrument according to claim 4,
The lid and the base are assembled on each wall existing at both ends of the base in the width direction while slightly deforming the opening side of the “U” -shaped base in the width direction. It is configured to be performed by engaging each protrusion protruding on both sides of the lid portion in the width direction with the recessed portion formed,
The spread prevention mechanism is configured by a protrusion provided on each end side in the width direction of the base, and a recess provided on the lid and engaged with the protrusion of the base.
In order to make it easy to assemble the lid part to the base part, a protrusion and a concave part constituting the spread preventing mechanism, and a protrusion of the lid part and the base part provided to assemble the lid part to the base part A current transformer for a measuring instrument, characterized in that the distance between the recesses is large. The current transformer for a measuring instrument according to claim 2,
The first cover portion is separated from the main body portion of the housing and is configured in a plate shape, and is provided to be rotatable with respect to the main body portion of the housing on the base end side,
In a state where the first cover portion is closed, one surface in the thickness direction of the housing that is provided with the first cover portion is substantially the same as the first cover portion. In the state where the first cover portion is open, an opening is provided on one side of the longitudinal end of the housing and on the convex side in the thickness direction. Formed,
The portion of the housing where the first cover portion is installed is formed in a “U” shape in a cross section by a plane perpendicular to the longitudinal direction when the first cover portion is closed. And
On the base end side of the first cover part, a cylindrical part extending in the width direction with a slit extending in the width direction is provided,
When the lid portion and the first cover portion are assembled to each other, the central portion of the cylindrical portion enters the central portion of the main body portion of the housing that is engaged with the first cover portion. A central shaft portion is provided extending long in the width direction, and a notch for allowing a part of the cylindrical portion to enter when the first cover portion rotates is adjacent to the central shaft portion. Provided parallel to the central axis,
The width of the slit is slightly smaller than the outer diameter of the central shaft portion,
When the lid portion and the first cover portion are assembled in a state where the lid portion and the first cover portion are in one plane, the cylindrical portion is elastically deformed and the slit is A current transformer for a measuring instrument, wherein the current transformer is configured to extend slightly and the central shaft portion enters inside the cylindrical portion, and the first cover portion is assembled to the lid portion. The current transformer for a measuring instrument according to claim 3,
The portion of the housing where the first cover portion is installed is formed in a “U” shape in a cross section by a plane perpendicular to the longitudinal direction when the first cover portion is closed. And
On the base end side of the first cover part, a cylindrical part extending in the width direction with a slit extending in the width direction is provided,
When the lid portion and the first cover portion are assembled to each other, the central portion of the cylindrical portion enters the central portion of the main body portion of the housing that is engaged with the first cover portion. A central shaft portion is provided extending long in the width direction, and a notch for allowing a part of the cylindrical portion to enter when the first cover portion rotates is adjacent to the central shaft portion. Provided parallel to the central axis,
The width of the slit is slightly smaller than the outer diameter of the central shaft portion,
When the lid portion and the first cover portion are assembled in a state where the lid portion and the first cover portion are in one plane, the cylindrical portion is elastically deformed and the slit is A current transformer for a measuring instrument, wherein the current transformer is configured to extend slightly and the central shaft portion enters inside the cylindrical portion, and the first cover portion is assembled to the lid portion. In the current transformer for measuring instruments of any one of Claim 4 or Claim 5,
On the base end side of the first cover part, a cylindrical part extending in the width direction with a slit extending in the width direction is provided,
When the lid portion and the first cover portion are assembled to each other, the central portion of the cylindrical portion enters the central portion of the main body portion of the housing that is engaged with the first cover portion. A central shaft portion is provided extending long in the width direction, and a notch for allowing a part of the cylindrical portion to enter when the first cover portion rotates is adjacent to the central shaft portion. Provided parallel to the central axis,
The width of the slit is slightly smaller than the outer diameter of the central shaft portion,
When the lid portion and the first cover portion are assembled in a state where the lid portion and the first cover portion are in one plane, the cylindrical portion is elastically deformed and the slit is A current transformer for a measuring instrument, wherein the current transformer is configured to extend slightly and the central shaft portion enters inside the cylindrical portion, and the first cover portion is assembled to the lid portion. In the current transformer for measuring instruments of any one of Claims 2-8,
One side in the thickness direction, which is a concave side when rotated by the predetermined angle, and there is a gap due to the rotation of the core unit between the core units joined to each other. A current transformer for a measuring instrument, characterized in that an inner cover of an elastic body is provided to prevent it from being formed.

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