JP2011106964A - Current detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a current detector with a small-sized projected area. <P>SOLUTION: The current detector 10 includes: a magnetic core 21 having a gap part 22; a core storage part 25 holding the magnetic core 21; a magnetoelectric conversion element 31 arranged in the gap part 22 and detecting a magnetic flux generating at the magnetic core 21; and a distribution member 40 connected to the magnetoelectric conversion element 31 and electrically connecting to an external equipment. The distribution member 40 is disposed in a position corresponding to the gap part 22 of the core storage part 25 by inserting the magnetoelectric conversion element 31 in the direction approximately parallel to thickness of the magnetic core 21 and arranging it in the gap part 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a current detection device.

A current detection device may be attached to an electrical junction box mounted on a vehicle or the like. As such a current detection device, for example, the one described in Patent Document 1 is known.
Patent Document 1 discloses a current detection device including a ring-shaped magnetic core through which a conductor as a current detection target can be inserted, and a magnetoelectric conversion element that is disposed in a gap portion of the magnetic core and detects the strength of a magnetic field. Is described. In this current detection device, a wiring material or the like for electrically connecting the magnetoelectric conversion element and the external device is arranged in the immediate vicinity of the region where the magnetic core and the magnetoelectric conversion element are arranged (patent) (Refer FIG. 1 (a) of literature 1).

JP 2006-292692 A

In the apparatus described in Patent Document 1, a region where the magnetic core and the magnetoelectric conversion element are arranged, and a region where the wiring material for electrically connecting the magnetoelectric conversion element and the external device is arranged, Since they are provided side by side in one plane, there is a problem that the projected area of the current detection device is large.
The present invention has been completed based on the above circumstances, and an object thereof is to reduce the projected area of the current detection device.

  In order to solve the above problems, the present invention detects a magnetic core having a gap portion, a core housing portion that houses the magnetic core, and a magnetic flux that is arranged in the gap portion and is generated in the magnetic core. A magnetoelectric conversion element; and a wiring member connected to the magnetoelectric conversion element and electrically connected to an external device, wherein the magnetoelectric conversion element is inserted in a direction substantially parallel to the thickness direction of the magnetic core. By arranging in the gap part, the wiring member is arranged at a position corresponding to the gap part of the core housing part.

  In the present invention, by arranging the magnetoelectric conversion element in the gap portion in a direction substantially parallel to the thickness direction of the magnetic core, the routing member is arranged at a position corresponding to the gap portion of the core housing portion. Is done. That is, in the present invention, the region where the routing member is disposed overlaps the range of the projected area of the core housing portion. As a result, according to the present invention, the projected area of the current detection device can be reduced.

The present invention may have the following configuration.
It is good also as a structure formed by attaching the electronic unit provided with the said magnetoelectric conversion element and the said wiring member to the core unit provided with the said magnetic body core and the said core accommodating part.
In general, a terminal portion electrically connected to another member such as a battery is provided at one end portion of the conductor, and the size of the terminal portion is determined by the amount of current flowing through the conductor. That is, when the current flowing through the conductor is increased, it is necessary to increase the size of the terminal portion by increasing the width and thickness thereof. When the size of the conductor terminal portion increases, a magnetic core having a large conductor insertion portion for inserting the conductor terminal portion is required. As described above, when the conductor insertion portion of the magnetic core is increased in accordance with the increase in the size of the conductor terminal portion, the magnetic core itself increases in size. This causes a problem that the current detection device becomes large.
However, according to the above configuration, since the electronic unit is assembled to the core unit, the electronic unit can be assembled after the conductor is inserted into the magnetic core of the core unit. That is, when inserting the conductor which becomes an electric current detection object through a magnetic body core, it is not necessary to insert from a terminal part. Therefore, even when the terminal portion of the conductor is enlarged, the magnetic core can be reduced in size by a method such as providing a conductor insertion portion or gap portion of the magnetic core in a part of the conductor. Can do. As a result, according to the above configuration, the current detection device can be further downsized.

  Furthermore, if it is set as the said structure, some parts which comprise each unit or a unit can be produced using a different material. In the structure of the present invention, it is preferable that the magnetoelectric conversion element and the magnetic core can be aligned with high accuracy. However, in the present invention, for example, only the portion interposed in the alignment has good processing accuracy. Using materials, it is possible to use other inexpensive materials. As a result, according to the above configuration, an effect of reducing the cost of the entire apparatus can be obtained.

  An engagement part may be formed on one of the core housing part and the routing member, and an engaged part on which the engagement part can be engaged may be formed on the other. According to this configuration, the core housing portion and the routing member can be easily and reliably aligned by engaging the engaging portion and the engaged portion.

  The cabling member includes an element cabling material connected to the magnetoelectric conversion element, a main body portion that accommodates the element cabling material, and an external device and the magnetoelectric conversion element that are detachably coupled to the main body portion. And a connector part for electrically connecting the two. With such a configuration, electrical connection between the external device and the magnetoelectric conversion element can be easily performed.

  The magnetic core has a conductor insertion portion through which a conductor that is a current detection target can be inserted, and in the core unit, the core housing portion is inserted in the conductor insertion portion of the magnetic core. It is good also as a structure integrated by molding.

  The conductor may be provided with an insertable part that is formed to be equal to or smaller than the width of the gap part of the magnetic core and that can be inserted through the gap part. With such a configuration, the magnetic core can be further downsized.

  According to the present invention, the projected area of the current detection device can be reduced.

1 is a longitudinal sectional view of a current detection device according to a first embodiment. The perspective view explaining the procedure of assembling the electronic unit to the core unit Cross section of current detector Schematic diagram schematically showing the inside of the main unit of the electronic unit Schematic diagram schematically showing the inside of the main unit of the electronic unit The perspective view explaining the procedure which attaches an electronic unit to a core unit in the electric current detection apparatus of Embodiment 2. Cross-sectional view of a current detection device described in another embodiment FIG. 7 is a longitudinal sectional view of the current detection device of FIG.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the current detection device 10 according to the present embodiment includes a core unit 20 having a magnetic core 21 and a core housing portion 25 that houses the magnetic core 21, and a substantially overlapped core unit 20. And a rectangular parallelepiped electronic unit 30.
First, the core unit 20 will be described. A bus bar 11 (conductor) made of a conductive material such as copper protrudes from the upper surface of the core housing portion 25 of the core unit 20 and the right side surface shown in FIG. The bus bar 11 protrudes from the side surface of the core housing portion 25 and includes a bus bar main body portion 12 disposed substantially parallel to the bottom surface 2 of the electrical connection box 1 and an upright portion 17 raised substantially vertically from the bus bar main body portion 12. And has a substantially L-shape. The bus bar main body 12 is placed on a table 3 provided on the bottom surface 2 of the electrical junction box 1.

A terminal portion 13 connected to another member (not shown) such as a battery or an inverter is provided at the upper end of the standing portion 17 of the bus bar 11. The size of the terminal portion 13 is determined by the amount of current flowing through the bus bar 11. Below the terminal portion 13 of the bus bar 11, as shown in FIG. 2, a neck portion 14 having a smaller width than the terminal portion 13, a U-shaped portion 15 having a U-shape, and a U-shaped portion 15. Furthermore, the narrow part 16 (insertable part 16) with a small width dimension continues. The U-shaped portion 15 of the bus bar 11 is formed by bending a portion whose development shape is wider than the constricted portion 16 to a size that allows the bus bar insertion portion 23 of the magnetic core 21 to be inserted.
The lower end of the standing portion 17 of the bus bar 11 is bent substantially vertically and continues to the bus bar main body portion 12. The U-shaped portion 15 of the bus bar 11 and the cross-sectional area of the bus bar main body portion 12 are preferably approximately the same in order to improve the molding yield of the bus bar 11.

  The constricted portion 16 is formed such that the width dimension is equal to or less than the width dimension A of the gap portion 22 of the magnetic core 21 and the length C is equal to or greater than the thickness dimension B of the magnetic core 21. The gap portion 22 of the core 21 can be smoothly inserted. In the present embodiment, the length C of the constricted portion 16 is set to be a little larger than the thickness dimension B of the magnetic core 21, that is, the minimum length necessary for attaching the magnetic core 21. Has been.

  2 and 3, the magnetic core 21 has a substantially C shape, and includes a gap portion 22 where the magnetoelectric conversion element 31 for detecting magnetic flux is disposed, and a bus bar insertion portion through which the bus bar 11 is inserted. 23 (conductor insertion portion 23).

The core accommodating portion 25 that accommodates the magnetic core 21 and the magnetic core 21 in a state where the bus bar 11 is inserted are integrated by molding.
Examples of the material constituting the core housing portion 25 include various resin materials such as polybutylene terephthalate (PBT), nylon, polypropylene (PP), and polyethylene (PE). These materials may contain fillers such as glass fibers. Of these, it is preferable to use an inexpensive resin such as PP or PE as the material of the portion not interposed in the alignment.

  On the upper surface of the core housing portion 25, an element insertion hole 27 into which a magnetoelectric conversion element 31 described later can be inserted is formed at a position corresponding to just above the gap portion 22 of the magnetic core 21. Further, on the upper surface of the core housing portion 25, two engagement holes 26, 26 that can be engaged with two engagement convex portions 33, 33 (engagement portions) formed on the main body portion 32 of the electronic unit 30. (Engaged portion) is formed (see FIGS. 2 and 3).

Next, the electronic unit 30 will be described. The electronic unit 30 is disposed in the gap portion 22 of the magnetic core 21 to electrically connect the magnetoelectric conversion element 31 that detects magnetic flux generated in the magnetic core 21, and the magnetoelectric conversion element 31 and an external device (not shown). And a wiring member 40 to be connected.
The wiring member 40 includes an element wiring material 34 connected to the magnetoelectric conversion element 31 and a main body 32 that houses the element wiring material 34.

As shown in FIG. 2, the main body portion 32 of the routing member 40 has a substantially rectangular parallelepiped shape, and an electric wire 36 connected to an external device (not shown) is led out from the upper surface of the main body portion 32. Two engaging convex portions 33 are formed at the lower end of the main body portion 32.
As shown in FIGS. 4 and 5, an electronic component 35 such as an antistatic capacitor and an element wiring material 34 that electrically connects the magnetoelectric conversion element 31 and an external device are accommodated in the main body 32. ing.

As the element routing material 34, for example, a printed board 34A as shown in FIG. 4 or a bus bar 34B (hereinafter referred to as “internal bus bar 34B”) as shown in FIG. 5 can be used.
FIG. 4 schematically shows the inside of the main body 32 using the printed circuit board 34 </ b> A as the element routing material 34. As shown in FIG. 4, an electronic component 35 is mounted on the printed board 34 </ b> A, the end of an electric wire 36 connected to an external device is connected to the upper end side, and the magnetoelectric conversion element 31 is connected to the lower end side. Is done.

  FIG. 5 schematically shows the inside of the main body 32 using the internal bus bar 34 </ b> B as the element routing material 34. As shown in FIG. 5, the electronic component 35 is arranged so as to connect the adjacent internal bus bars 34B, and the terminal of the electric wire 36 connected to the external device is connected to the upper end portion side of the internal bus bar 34B, and the lower end of the internal bus bar 34B. The magnetoelectric conversion element 31 is connected to the part side.

  As shown in FIGS. 1 and 2, the magnetoelectric conversion element 31 connected to the element routing material 34 is located below the engaging convex portion 33, that is, below the lower end portion of the main body portion 32 (on the main body portion 32. It is arranged on the outside.

  The main body 32 of the routing cord member 40 is produced by a method such as molding a resin material. Examples of the material constituting the main body 32 include various resin materials such as PBT, nylon, PP, and PE. These materials may contain fillers such as glass fibers. As a material of the main body 32 of the routing member 40, it is preferable to use a material having high rigidity such as PBT or nylon from the viewpoint of preventing rattling when attached to the core unit 20.

Next, a method for assembling the electronic unit 30 to the core unit 20 will be described.
First, the core unit 20 is produced. A bus bar 11 having a predetermined shape is cut out from the conductive metal plate and subjected to bending or the like so as to have a shape as shown in FIGS. The magnetic core 21 is attached to the bus bar 11 thus manufactured by the following procedure. First, the gap portion 22 of the magnetic core 21 is inserted into the constricted portion 16 of the bus bar 11. In the present embodiment, the narrow portion 16 of the bus bar 11 has a width dimension equal to or smaller than the width dimension A of the gap portion 22 of the magnetic core 21 and a length C equal to or greater than the thickness dimension B of the magnetic core 21. Therefore, the gap 22 of the magnetic core 21 can be inserted smoothly.

  Next, the bus bar 11 or the magnetic core 21 is moved so that the bus bar insertion portion 23 of the magnetic core 21 is arranged in the U-shaped portion 15 of the bus bar 11. Here, since the U-shaped portion 15 is processed in advance so that the bus bar insertion portion 23 can be inserted, it can be inserted into the bus bar insertion portion 23 of the magnetic core 21.

Next, the core unit 20 is obtained by integrating the magnetic core 21 and the core housing portion 25 with the bus bar 11 inserted therethrough by molding. The core unit 20 thus manufactured is attached to a predetermined position on the bottom surface 2 of the electrical junction box 1.
Next, the element wiring material 34 is accommodated in the main body portion 32 of the electronic unit 30, and the terminal of the electric wire 36 connected to the external device and the magnetoelectric conversion element 31 are connected to the element wiring material 34. 30 is produced.

  The magnetoelectric conversion element 31 of the electronic unit 30 thus manufactured is inserted into the element insertion hole 27 (a direction substantially parallel to the thickness direction of the magnetic core 21) from the upper side in FIGS. 1 and 2. The electronic unit 30 is assembled at a predetermined position of the core unit 20 by disposing it in the gap portion 22 of the magnetic core 21 and engaging the engaging projection 33 of the electronic unit 30 with the engaging hole 26 of the core unit 20. Can be found. In the state in which the electronic unit 30 is assembled to the core unit 20, as shown in FIG. 3, the electronic unit 30 (routing member 40) and the core unit 20 (core housing portion 25) overlap each other. That is, in this state, the electronic unit 30 is arranged within the range of the projected area of the core unit 20.

Next, the effect of this embodiment will be described.
In the present embodiment, the magnetoelectric conversion element 31 is disposed in the gap portion 22 by being inserted from the upper side to the lower side in FIG. 2 (a direction substantially parallel to the thickness direction of the magnetic core 21). Since the member 40 and the core accommodating part 25 overlap over the whole area, the projection area of the electric current detection apparatus 10 can be made small. As a result, according to the present embodiment, the current detection device 10 can be reduced in size.

In particular, in the current detection device 10 of the present embodiment, the core unit 20 and the electronic unit 30 are separate bodies. Therefore, when the bus bar 11 that is a current detection target is inserted into the magnetic core 21, the core unit 20 and the electronic unit 30 are inserted from the terminal portion 13. There is no need to let them. In addition, in the present embodiment, the bus bar 11 is provided with a constricted portion 16 (insertable portion 16) that is formed to be equal to or smaller than the width of the gap portion 22 of the magnetic core 21 and can be inserted through the gap portion 22.
Therefore, in this embodiment, even if the terminal portion 13 of the bus bar 11 is enlarged, the bus bar 11 is inserted into the gap portion 22 of the magnetic core 21 by inserting the constricted portion 16 of the bus bar 11 into the magnetic core. Therefore, it is not necessary to enlarge the bus bar insertion portion 23 of the magnetic core 21. As a result, according to the present embodiment, the magnetic core 21 can be downsized, and the current detection device 10 can be reliably downsized.

  If the bus bar 11 is provided with a portion having a small width dimension, the resistance value of the bus bar 11 may be increased. However, according to this embodiment, the length of the constricted portion 16 is used to attach the magnetic core 21. The required minimum length is set and the U-shaped portion 15 having a wide developed shape is provided adjacent to the constricted portion 16, so that an increase in the resistance value of the bus bar 11 can be reliably prevented. .

  As described above, in this embodiment, since the core unit 20 and the electronic unit 30 are separate bodies, each unit 20, 30 or part of the components constituting the unit can be manufactured using different materials. . In the present embodiment, it is preferable that the magnetoelectric conversion element 31 and the magnetic core 21 can be positioned with high accuracy. However, in this embodiment, for example, only the portion interposed in the alignment has processing accuracy. It is possible to use a good material and an otherwise inexpensive material. As a result, according to the present embodiment, the cost of the current detection device 10 as a whole can be reduced.

  Further, according to the present embodiment, the two engaging convex portions 33 and 33 are formed on the main body portion 32 of the electronic unit 30, and the engaging convex portions 33 and 33 are engaged with the core housing portion 25 of the core unit 20. Since two possible engagement holes 26 are formed, the electronic unit 30 and the core unit 20 can be easily and reliably aligned.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described with reference to FIG. The present embodiment is different from the first embodiment in that the routing member 40 includes a connector portion 41 that is detachably coupled to the main body portion 32 and electrically connects the external device and the magnetoelectric transducer 31. Constituent parts similar to those in the first embodiment are given the same reference numerals, and redundant descriptions are omitted.

As shown in FIG. 6, a plurality of terminals 37 are provided on the main body 32 of the electronic unit 30 with the tip of the terminals 37 facing upward. The main body portion 32 and the connector portion 41 to which the end of the electric wire 36 is connected can be fitted to each other. When the fitting of the main body portion 32 and the connector portion 41 is completed, the main body portion 32 and the connector portion 41 are locked by a known lock mechanism. Other configurations and operational effects are substantially the same as those of the first embodiment.
According to this embodiment, since the connector part 41 detachably coupled to the main body part 32 is provided, the electrical connection between the external device and the magnetoelectric conversion element 31 can be easily performed.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above-described embodiment, the electronic unit 30 has a configuration in which the entire area of the electronic unit 30 is disposed within the range of the projected area of the core unit 20. It may overlap with the range of the projected area of the core housing part 25.

  (2) In the above embodiment, the electronic unit 30 and the core unit 20 are shown as separate units. However, at least a part of the routing member 40 is arranged so as to fall within the range of the projected area of the core housing portion 25. It is good also as a structure which accommodated what was accommodated in one case.

  (3) In the above embodiment, as the engaging portion and the engaged portion, the two engaging convex portions 33 and 33 are provided on the main body portion 32 of the electronic unit 30 and the two engaging protrusions 33 are provided on the core housing portion 25 of the core unit 20. Although what provided the joint holes 26 and 26 was shown, the number of the engagement convex part 33 and the engagement holes 26 may be one, or may be three or more, and it is not necessary to provide these. Further, the electronic unit 30 may be provided with the engagement hole 26 in the main body 32 and the engagement convex portion 33 in the core housing portion 25, or provided with another form of engagement portion or engaged portion. May be.

  (4) In the embodiment described above, the bus bar 11 and the core housing part 25 that are inserted through the bus bar insertion part 23 of the magnetic core 21 are integrated by molding, but the core housing part 25 is shown. The bus bar 11 may be fixed by providing a locking portion of the bus bar 11.

  (5) In the above embodiment, the bus bar 11 provided with a portion (neck portion 16) having a width dimension equal to or smaller than the width dimension A of the gap portion 22 of the magnetic core 21 is shown. As shown in FIG. 7, a C-shaped portion 15a having a substantially C-shape may be provided by bending the bus bar 11 as described above. By doing so, as shown in FIG. 8, the length C1 of the constricted portion 16 can be shortened, and the current detecting device 10 can be made space-saving in the height direction. Also, the width dimension D1 can be made smaller in the current detection device 10 provided with the C-shaped portion 15a than the current detection device 10 according to the first embodiment provided with the U-shaped portion 15 (the width size is D in FIG. 1). This can save space. When attaching the magnetic core 21 to the bus bar 11 of this form, the portion of the C-shaped portion 15a of the bus bar 11 having a width dimension A or less of the gap portion 22 is inserted into the gap portion 22 of the magnetic core 21. The bus bar 11 is arranged at a predetermined position.

10 ... Current detection device 11 ... Bus bar (conductor)
16 ... Constriction (insertable part)
DESCRIPTION OF SYMBOLS 20 ... Core unit 21 ... Magnetic body core 22 ... Gap part 23 ... Bus-bar insertion part (conductor insertion part)
25 ... Core housing part 26 ... Engagement hole (engaged part)
DESCRIPTION OF SYMBOLS 30 ... Electronic unit 31 ... Magnetoelectric conversion element 32 ... Main part of electronic unit 33 ... Engagement convex part (engagement part)
34 ... element arrangement material 40 ... arrangement member 41 ... connector part

Claims (6)

A magnetic core having a gap portion, a core housing portion for housing the magnetic core, a magnetoelectric conversion element arranged in the gap portion for detecting magnetic flux generated in the magnetic core, and connected to the magnetoelectric conversion element A wiring member electrically connected to an external device,
The magnetoelectric transducer is inserted in a direction substantially parallel to the thickness direction of the magnetic core and disposed in the gap portion, thereby arranging the routing member at a position corresponding to the gap portion of the core housing portion. A current detection device characterized by that. The current detection device according to claim 1, wherein an electronic unit including the magnetoelectric conversion element and the wiring member is assembled to a core unit including the magnetic core and the core housing portion. An engaging portion is formed on one of the core housing portion and the routing member, and an engaged portion on which the engaging portion can be engaged is formed on the other. The current detection device according to claim 1 or 2. The cabling member includes an element cabling material connected to the magnetoelectric conversion element, a main body portion that accommodates the element cabling material, and an external device and the magnetoelectric conversion element that are detachably coupled to the main body portion. A current detecting device according to any one of claims 1 to 3, further comprising a connector portion that electrically connects the two. The magnetic core has a conductor insertion portion through which a conductor that is a current detection target can be inserted,
5. The core unit according to claim 2, wherein in the core unit, the core housing portion is integrated by molding while the conductor is inserted through the conductor insertion portion of the magnetic core. The current detection device according to claim 1. The current detection device according to claim 5, wherein the conductor is provided with an insertable portion that is formed to be equal to or less than a width dimension of the gap portion of the magnetic core and is capable of inserting the gap portion.

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