JPWO2017187809A1 - Current sensor - Google Patents

Abstract

The first magnetoelectric transducers 25a, 25e, 25f, and 25j having sensitivity axes orthogonal to the Y1-Y2 direction that is the inclination direction of the second current path portion CB2 with respect to the first current path portion CB1 are replaced with the second current path. It is provided on the first surface 16a on the part CB2 side (side closer to the second current path part CB2). Second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i having sensitivity axes orthogonal to the direction of the first current path portion CB1 are provided on the second surface 16b opposite to the second current path portion CB2. Yes.

Description

  The present invention relates to a current sensor that detects a current flowing in a current path to be measured, and more particularly to a current sensor that detects a current flowing in a current path to be measured using a magnetoelectric transducer.

In order to control and monitor various electronic devices, a current sensor that is attached to a measured current path and detects a current flowing through the measured current path is well known. As this type of current sensor, a current sensor using a magnetoelectric conversion element such as a Hall element or a magnetoresistive element is known. In order to improve the sensitivity of the magnetoelectric conversion element or reduce the influence from an external magnetic field, a plurality of magnetoelectric conversion elements are used. A conversion element may be used.
As described above, in a current sensor using a plurality of magnetoelectric conversion elements, a plurality of magnetoelectric conversion elements are arranged around the measured current path in accordance with the direction of the magnetic field generated around the measured current path.

In the current sensor, the positional relationship between the components may greatly affect the measurement accuracy.
In particular, when retrofitting to an electric wire, in order to increase the positional accuracy of each component, if each component is fixed, it is necessary to make a space where the electric wire passes when attaching to the electric wire. In particular, when the distance between the electric wires is narrow, the position where the magnetoelectric transducer is attached is limited.
In a current sensor that can be retrofitted to an electric wire, each part is fixed so that it does not move relatively, and as a structure that is less susceptible to the influence of an external magnetic field, the magnetoelectric transducers are arranged in two rows, Some are arranged so that the sensitivity is in the horizontal direction and the sensitivity of the other magnetoelectric transducers is in the vertical direction, so that even if the interval between the two rows is widened, the deterioration of the measurement accuracy is suppressed. The current sensor is configured such that a current path to be measured is located between magnetoelectric transducer elements arranged in two rows.
In such a current sensor, the magnetoelectric conversion element is disposed only on one side of the substrate on the assumption that the current path to be measured is a straight line.

International Publication No. WO2015 / 122064 International Publication WO2013 / 128993 JP 2012-247250 A JP 2015-38464 A JP 2014-174025 A

By the way, in the current sensor, there are cases where the current is measured not only for the straight measured current path but also for the bent measured current path.
However, in the conventional current sensor, the magnetoelectric conversion element is arranged on the assumption that the measured current path is a straight line, and there is a problem that the measurement accuracy is low when the current of the bent measured current path is measured. is there. That is, there is a problem that the measurement sensitivity varies depending on the position where the current path to be measured is bent.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a current sensor capable of reducing a change in measurement sensitivity even when a current path to be measured is bent.

  In order to solve the above-described problems of the prior art and achieve the above-described object, the current sensor of the present invention includes a first current path portion and a second current path portion bent with respect to the first current path portion. A plurality of first magnetoelectric transducers arranged so as to surround the first current path portion; and the first current path portion. A plurality of second magnetoelectric transducers arranged in two rows so as to sandwich the first current path portion, a current flows in a first current direction, and the second current path portion is a second current A current flows in a direction, and the plurality of first magnetoelectric transducers are arranged at point-symmetrical positions with a virtual point where the center of the first current path portion is arranged as a symmetric point, and the plurality of second magnetoelectric transducers Is arranged at a point-symmetrical position with the virtual point as a symmetric point, The second magnetoelectric conversion element detects a magnetic field in a direction in which the second current direction is projected onto a plane perpendicular to the first current direction, and the first magnetoelectric conversion element is perpendicular to the first current direction. Detecting a magnetic field in a direction in which the second current direction is projected onto a plane perpendicular to the first current direction, and in the second current direction, the first magnetoelectric conversion element is located outside the second magnetoelectric conversion element. The first magnetoelectric conversion element located near the second current path portion is closer to the second current path portion side in a direction parallel to the first current direction than the second magnetoelectric conversion element. positioned.

According to this configuration, since the arrangement of the plurality of first and second magnetoelectric conversion elements and the direction in which the magnetic field is detected are defined as described above, the plurality of first and second magnetoelectric conversion elements and second magnetoelectric elements are defined. By performing a calculation such as accumulation based on the output of the conversion element, measurement (detection) can be performed with the component corresponding to the magnetic field of the adjacent current path canceled.
According to this configuration, since the current path to be measured includes the second current path portion bent with respect to the first current path portion, the second current path portion is the first current path portion. Compared with the case of being in a straight line, the component of the magnetism generated by the current parallel to the column direction is reduced. Further, in the vicinity of the first current path portion, the plurality of magnetoelectric conversion elements of magnetism generated by the current flowing through the first current path portion are arranged as the distance from the second current path portion becomes longer. The component in the column direction becomes large.
On the other hand, the component in the direction perpendicular to the column direction of the magnetism generated by the current flowing through the second current path portion increases as it approaches the second current path portion around the second current path portion.

  In the present invention, the first magnetoelectric conversion element at a position close to the second current path portion is on the second current path portion side in a direction parallel to the first current direction with respect to the second magnetoelectric conversion element. Is located. That is, the first magnetoelectric conversion element is disposed at a position close to the second current path portion. Therefore, it is possible to increase the component of the direction perpendicular to the column direction of magnetism generated by the current flowing through the second current path portion at the position of the first magnetoelectric conversion element. The second magnetoelectric conversion element is positioned on the opposite side of the second current path portion with respect to the first magnetoelectric conversion element. That is, the second magnetoelectric transducer is disposed at a position far from the second current path portion. Therefore, the component in the column direction of magnetism generated by the current flowing through the first current path portion at the position of the second magnetoelectric conversion element can be increased.

  When the second current path portion approaches the first magnetoelectric conversion element, the sensitivity of the first magnetoelectric conversion element increases. On the other hand, when the second current path portion approaches the first magnetoelectric conversion element, the first current path portion in the vicinity of the second magnetoelectric conversion element is shortened, so that the sensitivity of the second magnetoelectric conversion element is lowered. Therefore, the change in sensitivity of the first magnetoelectric conversion element and the change in sensitivity of the second magnetoelectric conversion element cancel each other, so that the change in measurement sensitivity can be suppressed. Conversely, when the second current path portion is moved away from the first magnetoelectric conversion element, the sensitivity of the first magnetoelectric conversion element is lowered. On the other hand, when the second current path portion is moved away from the first magnetoelectric conversion element, the first current path portion in the vicinity of the second magnetoelectric conversion element becomes longer, so that the sensitivity of the second magnetoelectric conversion element is increased. Therefore, the change in sensitivity of the first magnetoelectric conversion element and the change in sensitivity of the second magnetoelectric conversion element cancel each other, so that the change in measurement sensitivity can be suppressed. As a result, even if the position of the second current path portion is shifted in the first current direction, a change in measurement sensitivity can be suppressed.

Preferably, the first magnetoelectric transducer is perpendicular to the first current direction and has a sensitivity axis in a direction less than 45 ° with respect to the direction perpendicular to the second current direction, The sensitivity axis of the second magnetoelectric conversion element is oriented in a direction less than 45 ° with respect to a direction parallel to the second current direction.
Preferably, the row formed by the plurality of second magnetoelectric transducers is a straight line, and the direction of the row is parallel to the direction in which the second current direction is projected onto a plane perpendicular to the first current direction. is there.
Preferably, the direction of the sensitivity axis of the first magnetoelectric transducer is perpendicular to the first current direction and perpendicular to the direction in which the second current direction is projected onto a plane perpendicular to the first current direction. The direction of the sensitivity axis of the second magnetoelectric transducer is a direction obtained by projecting the second current direction onto a plane perpendicular to the first current direction.
Preferably, the column formed by the plurality of second magnetoelectric conversion elements is a curve.
Preferably, the direction of the sensitivity axis of the first magnetoelectric conversion element and the second magnetoelectric conversion element is the direction of the induced magnetic field generated from the current flowing through the first current path portion.
Preferably, the first magnetoelectric transducer is located at an end of the row.

  Preferably, the current sensor of the present invention further includes a substrate on which the first magnetoelectric conversion element and the second magnetoelectric conversion element are provided, and the first magnetoelectric conversion element at a position close to the second current path portion is The second magnetoelectric conversion element is provided on the second surface of the substrate on the side opposite to the second current path portion side.

  According to this configuration, without providing special parts, the distance between the first magnetoelectric conversion element and the second current path portion is shortened, and the second magnetoelectric conversion element, the second current path portion, The distance between the two can be increased, and the measurement accuracy can be increased.

  Preferably, in the current sensor of the present invention, the first current path portion and the second current path portion are at right angles.

  According to this configuration, the column direction of the magnetic field generated by the current flowing through the first current path portion of the current path to be measured is formed by forming the first current path portion and the second current path portion at right angles. And the position of the first magnetoelectric conversion element of the component orthogonal to the column direction of the magnetic field generated by the current flowing through the second current path portion. Measurement sensitivity can be increased.

  The current sensor of the present invention includes a substrate, a plurality of first magnetoelectric transducers provided on the substrate, and a plurality of second magnetoelectric transducers provided on the substrate, and the substrate is two parallel. An arm portion and a root portion connecting the two arm portions, all the second magnetoelectric conversion elements are arranged side by side in the extending direction of the arm portion, and all the first magnetoelectric conversion elements are a plurality of Located at the end of the row of the second magnetoelectric transducers, the first magnetoelectric transducer detects a magnetic field in a direction orthogonal to the direction in which the arm extends, and the second magnetoelectric transducer is the arm Of the first magnetoelectric conversion element, the two first magnetoelectric conversion elements provided on the most distal side of the arm portion are provided on the first surface of the substrate, All the second magnetoelectric transducers are provided on a second surface opposite to the first surface. To.

According to this configuration, since the current path to be measured includes the second current path portion bent with respect to the first current path portion, the second current path portion is the first current path portion. Compared to the case of being in a straight line, the component of the magnetism generated by the current parallel to the second sensitivity axis is smaller. Further, in the vicinity of the first current path portion, the plurality of magnetoelectric conversion elements of magnetism generated by the current flowing through the first current path portion are arranged as the distance from the second current path portion becomes longer. The component in the column direction becomes large.
On the other hand, around the second current path portion, the component perpendicular to the column direction of the magnetism generated by the current flowing through the second current path portion becomes larger as the second current path portion is approached.

  In the present invention, when the second current path portion approaches the first magnetoelectric conversion element, the sensitivity of the first magnetoelectric conversion element increases. On the other hand, when the second current path portion approaches the first magnetoelectric conversion element, the first current path portion in the vicinity of the second magnetoelectric conversion element is shortened, so that the sensitivity of the second magnetoelectric conversion element is lowered. Therefore, the change in sensitivity of the first magnetoelectric conversion element and the change in sensitivity of the second magnetoelectric conversion element cancel each other, so that the change in measurement sensitivity can be suppressed. Conversely, when the second current path portion is moved away from the first magnetoelectric conversion element, the sensitivity of the first magnetoelectric conversion element is lowered. On the other hand, when the second current path portion is moved away from the first magnetoelectric conversion element, the first current path portion in the vicinity of the second magnetoelectric conversion element becomes longer, so that the sensitivity of the second magnetoelectric conversion element is increased. Therefore, the change in sensitivity of the first magnetoelectric conversion element and the change in sensitivity of the second magnetoelectric conversion element cancel each other, so that the change in measurement sensitivity can be suppressed. For this reason, even if the position of the second current path portion is shifted in the first current direction, a change in measurement sensitivity can be suppressed.

Preferably, the direction of the sensitivity axis of the first magnetoelectric conversion element is perpendicular to the first current direction and perpendicular to the second current direction, and the direction of the sensitivity axis of the second magnetoelectric conversion element. The direction is a direction parallel to the second current direction.
Preferably, the direction of the sensitivity axis of the first magnetoelectric conversion element and the second magnetoelectric conversion element is the direction of the induced magnetic field generated from the current flowing through the first current path portion.

  In the present invention, of the first magnetoelectric conversion elements, the two first magnetoelectric conversion elements provided on the most distal end side of the arm portion are provided on the first surface of the substrate. All the second magnetoelectric transducers are provided on a second surface opposite to the first surface. Therefore, the distance from the current path to the first magnetoelectric conversion element and the second magnetoelectric conversion element can be adjusted without providing special parts.

  Preferably, all the first magnetoelectric transducers of the current sensor of the present invention are provided on the first surface of the substrate, and all the second magnetoelectric transducers are on the opposite side of the first surface of the substrate. Formed on the second surface.

  According to this configuration, since the first magnetoelectric conversion element and the second magnetoelectric conversion element are provided on different surfaces of the substrate, the configuration can be simplified and the positioning of the magnetoelectric conversion element can be easily and accurately performed. , Manufacturing cost reduction and measurement accuracy can be improved.

  Preferably, the current sensor of the present invention includes four first magnetoelectric conversion elements and six or more second magnetoelectric conversion elements.

  According to this configuration, even if the positions of the adjacent current paths are shifted, it is possible to suppress deterioration in measurement accuracy.

  Preferably, in the current sensor according to the present invention, the second magnetoelectric conversion element located at the end of the first magnetoelectric conversion element and the second magnetoelectric conversion element is opposed to the opposite surface across the substrate. It is provided in the position to do.

  According to this configuration, since the second magnetoelectric conversion element and the first magnetoelectric conversion element located at the end are provided at positions facing each other, the overall configuration can be reduced. Therefore, retrofitting of the current sensor becomes easy.

  Preferably, the current sensor of the present invention includes four first magnetoelectric conversion elements and four second magnetoelectric conversion elements.

  According to this configuration, the overall configuration can be reduced. Further, since the temperatures of the paired magnetoelectric conversion elements are equal, even if the magnetoelectric conversion elements have temperature characteristics, it is possible to prevent the measurement accuracy from deteriorating.

  Preferably, the first magnetoelectric transducer of the current sensor of the present invention is provided at four vertices of a virtual rectangle where the current path to be measured is located, and the second magnetoelectric transducer passes through the center of gravity of the rectangle. Provided on the long side of the rectangle so as to be symmetric with respect to a virtual line parallel to the long side of the rectangle and point-symmetric with respect to the center of gravity, and the first magnetoelectric transducer is parallel to the short side of the rectangle The magnetic field is detected, the second magnetoelectric conversion element detects a magnetic field parallel to the long side, and the directions of the detectable magnetic fields of the first magnetoelectric conversion elements in a point-symmetric position around the center of gravity are the same or In other words, the direction of the detectable magnetic field between the second magnetoelectric transducers located in a point-symmetric position with respect to the center of gravity is the same or reverse.

According to this configuration, by arranging the first and second magnetoelectric conversion elements as described above, the region in which the first and second magnetoelectric conversion elements are arranged in the direction parallel to the short side of the rectangle. The distance between the current path to be measured and the adjacent current path (neighboring current path) can be reduced. As a result, the substrate can be downsized, that is, the current sensor can be downsized.
Further, the influence of the external magnetic field from the neighboring current path can be relatively reduced. Accordingly, since the influence of the external magnetic field on the first and second magnetoelectric conversion elements is reduced, the detection value from the first and second magnetoelectric conversion elements can be obtained stably.
Further, as described above, by defining the directions of the sensitivity axes of the first and second magnetoelectric transducers in parallel with the long and short sides of the virtual rectangle, the first and second magnetoelectric transducers are on the circumference. Compared to the case where the first and second magnetoelectric conversion elements are mounted on the substrate, the first and second magnetoelectric conversion elements can be easily mounted and the positional relationship between the substrate and the magnetoelectric conversion element can be reduced. Can be designed easily. Therefore, since the accuracy of the mounting angle and mounting position of the current path to be measured can be increased, the measurement accuracy can be improved.
Moreover, according to the said structure, the position of the 1st and 2nd magnetoelectric transducers should just be adjusted in the long side and short side direction of a virtual rectangle, and the design which raises a measurement precision becomes easy.

  ADVANTAGE OF THE INVENTION According to this invention, when the to-be-measured current path is bent, the current sensor which can make small the change of the measurement sensitivity by the bending position can be provided.

FIG. 1 is an external view showing a current sensor according to the first embodiment of the present invention. FIG. 2 is an exploded perspective view of the current sensor shown in FIG. FIG. 3 is a perspective view showing only the substrate, the first magnetoelectric conversion element, and the second magnetoelectric conversion element shown in FIG. FIG. 4 is a diagram for explaining the positional relationship between the substrate, the magnetoelectric transducer, and the current path to be measured. FIG. 5 is a view seen from the Z2 side to the Z1 side shown in FIG. 1 for explaining the arrangement of the magnetoelectric conversion elements on the substrate shown in FIG. FIG. 6 is a diagram for explaining the sensitivity axis of the magnetoelectric transducer shown in FIG. FIG. 7 is a view for explaining a modification of the current sensor of the first embodiment shown in FIG. FIG. 8 is a diagram showing the relationship between the distance between the current sensor and the like shown in FIG. 1 and the second current path portion, and the magnetic field detection sensitivity. FIG. 9 is another modification of the current sensor according to the first embodiment of the present invention. FIG. 10 is still another modification of the current sensor according to the first embodiment of the present invention. FIG. 11 is an external perspective view for explaining the arrangement of the first magnetoelectric conversion element and the second magnetoelectric conversion element on the substrate in the second embodiment of the present invention. FIG. 12 is a diagram for explaining the arrangement of the magnetoelectric conversion elements on the substrate of the current sensor shown in FIG. FIG. 13 is a diagram illustrating the relationship between the distance between the current sensor and the like shown in FIG. 11 and the second current path portion, and the magnetic field detection sensitivity.

<First Embodiment>
FIG. 1 is an external view showing a current sensor 101 according to the first embodiment of the present invention. FIG. 2 is an exploded perspective view of the current sensor 101 shown in FIG. FIG. 3 is a perspective view showing only the substrate 16 shown in FIG. 2, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i. FIG. 4 is a diagram for explaining the positional relationship among the substrate 16, the magnetoelectric transducer 15 and the measured current path CB. FIG. 5 is a diagram for explaining the arrangement of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i on the substrate 16 shown in FIG. FIG. 2 is a diagram viewed from Z2 shown in FIG. FIG. 6 illustrates the sensitivity axes (the direction in which magnetism is sensed) of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i shown in FIG. FIG.

  As shown in FIGS. 2 to 6, the current sensor 101 according to the first embodiment of the present invention is a first magnetoelectric transducer that detects magnetism (magnetic field) generated when a current flows through the current path CB to be measured. 25a, 25e, 25f, 25j, second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, 25i, and a substrate 16 on which the magnetoelectric conversion elements are arranged. The current sensor 101 includes a housing 11 having a housing portion 11s for housing the substrate 16, a first magnetoelectric transducer 25a, 25e, 25f, 25j, and a second magnetoelectric transducer 25b, 25c, 25d, 25g, 25h, A connector 13 having an extraction terminal 13t for taking out an electric signal from 25i and a holding member 14 for fixing and holding the measured current path CB are provided.

  As shown in FIG. 1, the measured current path CB has a bent shape, and includes a first current path portion CB1 and a second current path portion CB2 that is inclined with respect to the first current path portion CB1. . In the present embodiment, the first current path portion CB1 and the second current path portion CB2 are orthogonal to each other, the first current path portion CB1 extends in the Z1-Z2 direction, and the second current path portion CB2 is Y1- It extends in the Y2 direction. A magnetic field along the XY plane is generated around the first current path portion CB1 by the current I flowing in the first current path portion CB1 in the first current direction (direction from Z2 toward Z1). Further, a magnetic field along the XZ plane is generated around the second current path portion CB2 by the current I flowing through the second current path portion CB2 in the second current direction (direction from X1 to X2). The curvature (R) of the portion where the measured current path CB is bent may be significantly different from that shown in the figure. For example, the measured current path CB may be bent with a large curvature over the entire range facing the housing 11.

In the current sensor 101, the magnetoelectric conversion element is mounted on both sides of the substrate 16. That is, the first magnetoelectric transducers 25a, 25e, 25f, and 25j having sensitivity axes orthogonal to the Y1-Y2 direction that is the inclination direction of the second current path portion CB2 with respect to the first current path portion CB1 are It is provided on the first surface 16a on the current path portion CB2 side (side closer to the second current path portion CB2).
Further, the second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i having sensitivity axes orthogonal to the direction of the first current path portion CB1 are connected to the opposite side of the second current path portion CB2 (second current path portion CB2). It is provided on the second surface 16b on the side far from CB2.
Thereby, as will be described later, it is possible to reduce the measurement error between the case where the measured current path CB is a straight line and the case where it is bent.
Here, the sensitivity axis is the direction in which the magnetoelectric transducer senses magnetism. In this embodiment, as shown in FIG. 2 etc., the board | substrate 16 has the two arm parts 161 and 162 extended in the Y1-Y2 direction on both sides of the notch 17. As shown in FIG.
The second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are arranged in two rows on the arm portions 161 and 162 along the Y1-Y2 direction. The first magnetoelectric conversion elements 25a, 25e, 25f, and 25j are provided at the ends of the two rows, respectively.
The second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i detect the magnetic field in the column direction (the Y1-Y2 direction, the direction in which the arm portions 161 and 162 extend).
The first magnetoelectric transducers 25a, 25e, 25f, and 25j detect a magnetic field in the X1-X2 direction orthogonal to the column.

Hereinafter, each component will be described in detail.
The casing 11 is made of a synthetic resin material. The housing 11 includes a box-shaped case 31 whose upper side is open, and a plate-like cover 41 that closes the opening of the case 31, and a housing portion 11 s that houses the substrate 16 inside the case 31. Is formed. In addition, although the synthetic resin material was used for the material of the housing | casing 11, it is not limited to this, For example, if it is not a ferromagnetic body, you may make it the structure using a metal material.

  The case 31 is formed with a recess (concave groove) 32 cut out from one side thereof toward the center of the case 31, and the current path CB to be measured is introduced and held in the recess 32. It is configured. The back wall 32a of the recess 32 is formed in a shape complementary to the outer peripheral surface of the current path CB to be measured. In the present embodiment, the back wall 32a of the recess 32 is formed to be curved in an arc shape so as to correspond to the outer peripheral surface of the cylindrical current path CB to be measured. In addition, notches 32c that lock the free end side of the clip spring 14K are formed in opposing positions on the inner wall 32b facing the case 31 that is continuous with the inner wall 32a. The notch 32c is notched downward from the upper end side of the inner wall 32b, and the end surface on the entrance side is formed to be inclined outward. The measured current path CB is sandwiched by the clip spring 14K protruding from the notch 32c into the recess 32 with the back side of the outer peripheral surface thereof in contact with the back wall 32a of the recess 32, It is held with respect to the housing 11. A position sandwiched between the back wall 32 a of the recess 32 and the clip spring 14 </ b> K is an arrangement position PP of the measured current path CB with respect to the housing 11. In the present embodiment, the arrangement position PP is a center of gravity PP of a virtual rectangle L described later.

  In the cover 41, an opening 42 having the same shape is formed on one side so as to correspond to the recess 32 of the case 31, and the connector 13 is formed on a side opposite to the side where the opening 42 is formed. An opening 43 is formed for exposing the upper end of the housing 11 to the outside of the housing 11.

  The holding member 14 is a member for fixing and holding the measured current path CB. The holding spring 14 holds the outer edge of the measured current path CB and holds the clip spring 14K, and the measured current path CB is disposed at the position shown in FIG. And a pressing member 14H that presses the clip spring 14K after being disposed on the PP.

  The substrate 16 is formed in a size that can be stored in the storage portion 11 s of the case 31, and a notch 17 is formed in one side portion thereof for inserting the measured current path CB from the side. The substrate 16 is formed in a shape similar to the bottom surface portion of the storage portion 11 s, and a notch portion 17 having a complementary shape with the concave portion 32 of the case 31 is formed.

2-6, in the vicinity of the notch 17 of the substrate 16, a plurality of first magnetoelectric transducers 25a, 25e, 25f, 25j and second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, 25i is arranged. The total number of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i is ten. A connector 13 is disposed in the vicinity of the side facing the side where the notch 17 is formed.
Detailed arrangement positions of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i will be described later.

  The connector 13 includes a plurality of terminals that are electrically connected to a mating connector (not shown). Among these terminals, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion are included. An extraction terminal 13t is provided for extracting an electrical signal from the elements 25b, 25c, 25d, 25g, 25h, and 25i. The connector 13 includes an insulating base 13K for fitting with a mating connector (not shown). For example, a flexible printed circuit (FPC) or the like may be used instead of the connector 13.

The first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are currents that detect magnetism generated when a current flows through the measured current path CB. For example, a magnetic sensing element using a giant magnetoresistive effect (referred to as a GMR (Giant Magneto Resistive) element) can be used.
In this magnetoelectric conversion element 15, after a GMR element is fabricated on a silicon substrate, the cut-out chip is packaged with a thermosetting synthetic resin, and a lead terminal for signal extraction is electrically connected to the GMR element. Has been configured. The lead terminal is soldered to the substrate 16. In the present embodiment, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i have the same characteristics.

As shown in FIGS. 2 to 6, in the vicinity of the notch 17 of the substrate 16, the first magnetoelectric conversion elements 25 a, 25 e, 25 f, 25 j and the second magnetoelectric conversion elements 25 b, 25 c, 25 d, 25 g, 25 h, 25 i are arranged. Has been placed.
In FIG. 6, the sensitivity axes of the first magnetoelectric transducers 25a, 25e, 25f, and 25j are parallel to the X1-X2 direction, and the second magnetoelectric transducers 25b, 25c, 25d, 25g, and 25h are indicated by arrows. 25i is parallel to the Y1-Y2 direction. That is, the “second current direction” (Y1 to Y2) in which the current flows in the second current path portion CB2 also in the “first current direction” (direction from Z2 to Z1) in which the current I flows in the first current path portion CB1. The direction of the sensitivity axis of the first magnetoelectric transducers 25a, 25e, 25f, and 25j is parallel to the X1-X2 direction that is also orthogonal to the direction toward the head. Further, the “second current direction” in which the current flows through the second current path portion CB2 is parallel to the directions of the sensitivity axes of the second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i.

  As shown in FIG. 5, in the current sensor 101, the first magnetoelectric transducers 25a, 25e, 25f, 25j and the second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, 25i is provided. The center of gravity PP is the center of the cross section (X, Y cross section) of the measured current path CB. The notch 17 has a shape that allows the center of the measured current path CB to be positioned at the center of gravity of the virtual rectangle L when the current sensor 101 is positioned with respect to the measured current path CB.

As shown in FIG. 5, the first magnetoelectric conversion elements 25a and 25e and the second magnetoelectric conversion elements 25b, 25c and 25d are arranged on the substrate 16 on the left side (X2 direction side) of the notch 17 when viewed from the Y1 direction. Yes.
The first magnetoelectric conversion elements 25f and 25j and the second magnetoelectric conversion elements 25g, 25h and 25i are arranged on the substrate 16 on the right side (X1 direction side) of the notch 17 when viewed from the Y1 direction.

In the current sensor 101, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j are disposed on the first surface 16a (the surface on the Z1 side) of the substrate 16, and the second magnetoelectric conversion elements 25b, 25c, 25d, and 25g. , 25h, 25i are disposed on the second surface 16b (the surface on the Z2 side) of the substrate 16. Here, the first surface 16a of the substrate 16 is located on the second current path portion CB2 side of the measured current path CB with respect to the second surface 16b.
The first magnetoelectric transducers 25a, 25e, 25f, and 25j are arranged at the four vertices of the virtual rectangle L.

The second magnetoelectric conversion elements 25b, 25c, and 25d are disposed on the long side L1 of the rectangle L, and the second magnetoelectric conversion elements 25g, 25h, and 25i are disposed on the long side L2 of the rectangle L.
The second magnetoelectric conversion elements 25c and 25h are disposed on the long side L2 that is orthogonal to the long side L1 and passes through the center of gravity PP.
The first magnetoelectric conversion elements 25a and 25e are arranged in line symmetry with the first magnetoelectric conversion elements 25f and 25j, respectively, with respect to the first virtual line IL1 that is parallel to the long sides L1 and L2 and passes through the center of gravity PP.
The second magnetoelectric conversion elements 25b, 25c, and 25d are arranged symmetrically with the second magnetoelectric conversion elements 25g, 25h, and 25i with respect to the first virtual line IL1.

The first magnetoelectric conversion elements 25a and 25e are arranged point-symmetrically with the magnetoelectric conversion elements 25f and 25j, respectively, with respect to the center of gravity PP of the rectangle L.
The second magnetoelectric conversion elements 25b, 25c, and 25d are arranged point-symmetrically with the magnetoelectric conversion elements 25g, 25h, and 25i, respectively, with respect to the center of gravity PP of the rectangle L.

  Thus, by arranging the first magnetoelectric conversion elements 25a, 25e, 25f, 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, 25i, the magnetoelectric conversion elements are arranged at equal intervals on the circumference. Compared with the case where it is provided (general current sensor), the arrangement space of the magnetoelectric conversion element can be reduced while the arrangement of the magnetoelectric conversion element is capable of inserting the measured current path CB from the side.

That is, in the present embodiment, the first magnetoelectric conversion element 25a, the second magnetoelectric conversion elements 25b, 25c, and 25d and the first magnetoelectric conversion element 25e are disposed on the long side L1 of the rectangle L. Further, the first magnetoelectric conversion element 25f, the second magnetoelectric conversion elements 25g, 25h, 25i and the first magnetoelectric conversion element 25j are disposed on the long side L2 of the rectangle L.
Therefore, the distance in the short side L3 direction (X direction) can be shortened. That is, the distance between the measured current path CB and the adjacent current path can be reduced.
As a result, the first magnetoelectric transducers 25a, 25e, 25f, and 25j in the direction perpendicular to the direction in which the notches 17 are formed (the direction in which the second virtual line IL2 extends) are compared with the arrangement area of the general magnetoelectric transducers. And the arrangement | positioning area | region of 2nd magnetoelectric conversion element 25b, 25c, 25d, 25g, 25h, 25i can be narrowed, and the size reduction of the board | substrate 16, ie, the size reduction of the current sensor 201, is possible. In particular, the width of the left and right arm portions 161 and 162 of the notch 17 can be reduced.

The direction of the sensitivity axis (the direction in which magnetism is sensed) of the first magnetoelectric transducers 25a, 25e, 25f, and 25j is parallel to the short side L2 of the rectangle L and is one direction along the rectangle L.
The sensitivity axes of the first magnetoelectric conversion elements 25a and 25f are directed in the X1 direction, and the sensitivity axes of the first magnetoelectric conversion elements 25e and 25j are directed in the X2 direction.

The directions of the sensitivity axes of the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are parallel to the long side L1 of the rectangle L and are unidirectional along the rectangle L.
The sensitivity axes of the second magnetoelectric conversion elements 25b, 25c, and 25d are oriented in the Y1 direction, and the sensitivity axes of the second magnetoelectric conversion elements 25g, 25h, and 25i are oriented in the Y2 direction.
That is, the first magnetoelectric conversion element 25a, the second magnetoelectric conversion elements 25b, 25c, and 25d, and the first magnetoelectric conversion element 25e are the first magnetoelectric conversion element 25f and the second magnetoelectric conversion element that are in a point-symmetrical position around the center of gravity PP. The directions of the sensitivity axes with respect to 25g, 25h, 25i and the first magnetoelectric transducer 25j are point-symmetric (reverse).
In the arithmetic circuit at the subsequent stage, the outputs of the first magnetoelectric conversion elements 25a, 25e, 25f, 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, 25i are added to obtain the magnetic field of the measured current path CB. The component corresponding to the current is accumulated and validated, and the component corresponding to the magnetic field of the adjacent current path is canceled.

In the current sensor 101, as shown in FIGS. 2 to 6, the magnetoelectric conversion element is mounted on both sides of the substrate 16. That is, the first magnetoelectric transducers 25a, 25e, 25f, and 25j having sensitivity axes orthogonal to the Y1-Y2 direction, which is the direction in which the current in the second current path portion CB2 flows with respect to the first current path portion CB1. The first surface 16a on the second current path portion CB2 side (side closer to the second current path portion CB2) is provided.
Further, the second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i having sensitivity axes orthogonal to the direction of the first current path portion CB1 are connected to the opposite side of the second current path portion CB2 (second current path portion CB2). It is provided on the second surface 16b on the side far from CB2. That is, the magnetoelectric conversion element is mounted on both sides.
The present invention is a current sensor based on the same principle as the current sensors described in International Publication WO2015 / 122064 and International Publication WO2013 / 128993. The direction of the sensitivity axis of the first magnetoelectric conversion element positioned at the end is orthogonal to the direction of the sensitivity axis of the second magnetoelectric conversion element positioned other than the end. When the current path is bent, the measurement sensitivity of the first magnetoelectric conversion element near the bent portion of the first magnetoelectric conversion elements is increased, while the measurement sensitivity of the other magnetoelectric conversion elements is decreased. That is, the sensitivity of the two magnetoelectric conversion elements increases, while the sensitivity of the other magnetoelectric conversion elements decreases. For this reason, in the present invention, the sensitivity of the two magnetoelectric conversion elements is greatly increased by bending the current path, thereby canceling the sensitivity reduction of many other magnetoelectric conversion elements.
Thereby, the change of the measurement sensitivity by the difference in the position where the to-be-measured current path CB bends can be made small.

  That is, in the current sensor 101, the current path CB to be measured includes the second current path portion CB2 that is bent at a right angle to the first current path portion CB1, and therefore the second current path portion CB2 is the first current path portion. Compared with the case of being in line with CB1, the component parallel to the second magnetic sensitivity axis (Y1-Y2 direction) generated by the current flowing through the measured current path CB is smaller. Further, in the vicinity of the first current path portion CB1, as the distance from the second current path portion CB2 increases, the component parallel to the second sensitivity axis of the magnetism generated by the current flowing through the first current path portion CB1 increases. Become. On the other hand, around the second current path portion CB2, parallel to the sensitivity axis (X1-X2 direction) of the magnetic first magnetoelectric transducer generated by the current flowing through the second current path portion CB2 as it approaches the second current path portion CB2. Ingredients become larger.

  Here, the first magnetoelectric transducers 25 a and 25 j are provided on the ends (open ends) 16 c and 16 d of the two arms 161 and 162 of the first surface 16 a of the substrate 16. Therefore, the component parallel to the first sensitivity axis of magnetism generated by the current flowing through the second current path portion CB2 at the position of the first magnetoelectric transducers 25a and 25j becomes large.

The second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are provided on the surface 16b of the substrate 16 opposite to the second current path portion CB2. Therefore, the component parallel to the sensitivity axis of the magnetic second magnetoelectric conversion element generated by the current flowing through the first current path portion CB1 at the position of the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i becomes large.
Thereby, even if the position where the measured current path CB is bent changes, the change in measurement sensitivity can be suppressed.

  Further, since the second current path portion CB2 is perpendicular to the first current path portion CB1, the second magnetoelectric conversion element having a component parallel to the sensitivity axis of the magnetic field generated by the current flowing through the first current path portion CB1. 25b, 25c, 25d, 25g, 25h, 25i, and the magnitude of the component parallel to the sensitivity axis of the magnetic field generated by the current flowing through the second current path portion CB2, at the position of the first magnetoelectric transducers 25a, 25j. The height can be increased and the measurement sensitivity can be increased.

  In the current sensor 101, when the current flowing through the measured current path CB shown in FIG. 1 is measured, the sensitivity of the first magnetoelectric conversion elements 25a and 25j is increased, and the sensitivity of the first magnetoelectric conversion elements 25e and 25f is decreased. The second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i all have reduced sensitivity, but the respective magnetoelectric conversion elements are arranged so that changes in measurement sensitivity are offset as a whole.

  In addition, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are provided on different surfaces of the same substrate 16, thereby providing the first magnetoelectric conversion elements. And the second magnetoelectric transducer can be positioned with high accuracy and easily at different distances from the second current path portion CB2, and improvement in measurement accuracy and reduction in manufacturing cost can be realized at the same time.

  As shown in FIGS. 2 to 6, four first magnetoelectric transducers 25a, 25e, 25f, and 25j and six second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i are arranged. Thus, even if the positions of the adjacent current paths are shifted, it is possible to suppress deterioration in measurement accuracy.

In the example of FIG. 6, the direction of the sensitivity axis of the first magnetoelectric conversion element 25f is the X2 direction opposite to that of the first magnetoelectric conversion element 25a, and the direction of the sensitivity axis of the first magnetoelectric conversion element 25j is the first magnetoelectric conversion. The X1 direction opposite to that of the element 25e may be used, and the direction of the sensitivity axis of the second magnetoelectric conversion elements 25g, 25h, and 25i may be the same Y1 direction as that of the magnetoelectric conversion elements 25b, 25c, and 25d.
In this case, in the subsequent arithmetic circuit, the first magnetoelectric conversion elements 25f and 25j and the second magnetoelectric conversion elements 25g and 25h are output from the outputs of the first magnetoelectric conversion elements 25a and 25e and the second magnetoelectric conversion elements 25b, 25c and 25d. , 25i is subtracted, and the component corresponding to the magnetic field of the current path CB to be measured is accumulated and validated, and the component corresponding to the magnetic field of the adjacent current path is canceled.

As described above, according to the current sensor 101, the first magnetoelectric transducers 25a, 25e, 25f, and 25j having sensitivity axes orthogonal to the Y1-Y2 direction are connected to the second current path portion CB2 side (second current path). The second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i provided on the first surface 16a on the first surface 16a on the side close to the portion CB2 are arranged on the side opposite to the second current path portion CB2 (second current path). It was provided on the second surface 16b on the side far from the portion CB2. As a result, the sensitivity to magnetism as a whole can be increased by the current flowing through the measured current path CB, and the measurement accuracy can be increased.
As a result, it is possible to suppress a change in measurement sensitivity when the measured current path is a straight line and when the measured current path is bent like the measured current path CB.

<Modification of First Embodiment>
FIG. 7 shows a modification of the above-described current sensor 101. The first magnetoelectric conversion elements 25a and 25j are disposed on the first surface 16a, and the first magnetoelectric conversion elements 25e and 25f and all the second magnetoelectric conversion elements 25b are arranged. , 25c, 25d, 25g, 25h, and 25i are current sensors 201 arranged on the second surface 16b.

FIG. 8 is a diagram illustrating the relationship between the distance H between the current sensors 101 and 202 and the second current path portion CB2 and the magnetic field detection sensitivity. In FIG. 8, the horizontal axis indicates the distance H, and the vertical axis indicates the sensitivity when the magnetic field detection sensitivity is 100% when the measured current path CB is a straight line.
As shown in FIG. 8, the current sensor 201 shown in FIG. 7 has the smallest change in the magnetic field detection sensitivity (G1), and the current sensor 101 shown in FIGS. 2 to 6 has the second smallest change (G2). As shown in FIG. 8, the magnetic field detection sensitivity is the third when all the magnetoelectric conversion elements are arranged on the second surface 16b (G3), and all the magnetoelectric conversion elements are arranged on the first surface 16a. When it is set, the change in sensitivity is the largest (G4).

  Further, as shown in FIGS. 2 to 6, the first magnetoelectric conversion elements 25a, 25e, 25f, 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, 25i are arranged, so that the magnetoelectric conversion element 25a is arranged. The width in the X direction of the arrangement area of ˜25 l can be minimized, and the distance between the measured current path CB and the adjacent current path can be reduced. Thereby, the substrate 16 can be downsized, that is, the current sensor 101 can be downsized. In particular, the width of the left and right arm portions 161 and 162 of the notch 17 can be reduced.

  Further, according to the current sensor 101, the first magnetoelectric conversion elements 25a, 25e, 25f, 25j and the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, 25i are arranged as shown in FIGS. Thus, it is possible to relatively reduce the influence of the external magnetic field from the neighboring current paths arranged at adjacent positions. Accordingly, since the influence of the external magnetic field on the magnetoelectric conversion element is reduced, the detection value from the magnetoelectric conversion element can be obtained stably. Thus, it was confirmed by simulation that the influence of the adjacent electric wires could be removed.

<Other Modifications of First Embodiment>
In another modification, as shown in FIG. 9, the current sensor 101 arranges the second magnetoelectric transducers 25b to 25d on a circumference centered on the center of gravity PP of the first current path portion CB1. Similarly, the second magnetoelectric transducers 25g to 25i are arranged on the same circumference. The first magnetoelectric transducers 25a, 25e, 25f, and 25j are also arranged on the same circumference. In this case, the second magnetoelectric transducers 25b to 25d are arranged in two rows so as to surround the current path CB along the circumference, and the first magnetoelectric transducers 25a, 25e, 25f, and 25j are arranged in a row. Located at the end. That is, the column in which the magnetoelectric conversion elements 25a to 25j are arranged is not limited to a straight line but may be a curved line.

  The directions of the sensitivity axes of the second magnetoelectric conversion elements 25b to 25d and 25g to i are tangential to the circumference, and the directions of the sensitivity axes of the second magnetoelectric conversion elements 25b to 25d and 25g to i are The second current direction is less than 45 °. If the sensitivity axes of the second magnetoelectric conversion elements 25b to 25d and 25g to 25i are less than 45 ° with respect to the second current direction, the second magnetoelectric conversion elements 25b to 25d and 25g to 25i correspond to the second current direction. A magnetic field in a direction parallel to (the direction from Y1 to Y2) can be detected. The direction of the sensitivity axis of the first magnetoelectric transducer is arranged so as to be a tangential direction of the circumference and less than 45 ° with respect to the X1-X2 direction. If the sensitivity axes of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j are less than 45 ° with respect to the X1-X2 direction, the first electroelectric conversion elements 25a, 25e, 25f, and 25j are in the X1-X2 direction. Magnetic field in a direction parallel to the direction can be detected. Note that the X1-X2 direction is a direction perpendicular to the first current direction and perpendicular to the second current direction, as described above.

  When the magnetoelectric conversion elements 25a to 25j are arranged as shown in FIG. 9, the current sensor is enlarged, but the measurement accuracy can be increased. Further, when the second current path portion CB2 is not bent with respect to the first current path portion CB1, a comparison is made as follows. When the second current path CB2 is bent, the sensitivity of the first magnetoelectric conversion elements 25a and 25j is increased, and the sensitivity of the first magnetoelectric conversion elements 25e and 25f is decreased. Further, the sensitivity of the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i is all reduced as in the first embodiment described above. For this reason, by adjusting the arrangement positions of the magnetoelectric conversion elements 25a to 25j, the measurement sensitivity can be kept constant as a whole regardless of the bending rate of the measured current CB.

<Still another modification of the first embodiment>
When the current path CB has a flat shape, the induced magnetic field generated by the current flowing through the current path CB is elliptical. In this case, as shown in FIG. 10, the current sensor 101 arranges the second magnetoelectric transducers 25b to 25d on an ellipse along the induction magnetic field. Similarly, the second magnetoelectric transducers 25g to 25i are arranged on the same ellipse. The first magnetoelectric transducers 25a, 25e, 25f, and 25j may be located outside the ellipse as long as they are outside the second magnetoelectric transducer in the second current direction. However, the first magnetoelectric transducers 25a and 25j are symmetric with respect to the first virtual line IL1. Similarly, the first magnetoelectric transducers 25e and 25f are line symmetric with the first virtual line IL1. Furthermore, the first magnetoelectric transducers 25a and 25e are line symmetric with respect to the second virtual line IL2. Similarly, the first magnetoelectric transducers 25f and 25j are symmetric with respect to the second virtual line IL2.

  The direction of the sensitivity axis of the second magnetoelectric conversion element is an elliptical tangential direction, and the direction of the sensitivity axis of the second magnetoelectric conversion element is less than 45 ° with respect to the second current direction. Deploy. If the sensitivity axes of the second magnetoelectric conversion elements 25b to 25d and 25g to 25i are less than 45 ° with respect to the second current direction, the second magnetoelectric conversion elements 25b to 25d and 25g to 25i correspond to the second current direction. A magnetic field in a direction parallel to (the direction from Y1 to Y2) can be detected. The orientation of the sensitivity axes 25a, 25e, 25f, and 25j of the first magnetoelectric conversion element is arranged to be less than 45 ° with respect to the X1-X2 direction. If the sensitivity axes of the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j are less than 45 ° with respect to the X1-X2 direction, the first electroelectric conversion elements 25a, 25e, 25f, and 25j are in the X1-X2 direction. Magnetic field in a direction parallel to the direction can be detected. As described above, the X1-X2 direction is a direction perpendicular to the first current direction and perpendicular to the second current direction. The direction of the sensitivity axis of the first magnetoelectric transducers 25a, 25e, 25f, and 25j is the direction of the induced magnetic field. For this reason, the directions of the sensitivity axes of the first magnetoelectric transducers 25a and 25f are point-symmetric with respect to the center of gravity PP of the current path CB. Similarly, the directions of the sensitivity axes of the first magnetoelectric transducers 25e and 25j are point-symmetric with respect to the center of gravity PP of the current path CB.

  If each magnetoelectric transducer 25a-25j is arrange | positioned like FIG. 10, even if the current path CB is flat shape, it can make the measurement accuracy of a current sensor high. Further, when the second current path portion CB2 is not bent with respect to the first current path portion CB1, a comparison is made as follows. The first magnetoelectric conversion elements 25a and 25j have increased sensitivity, and the first magnetoelectric conversion elements 25e and 25f have reduced sensitivity. Further, the sensitivity of the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i is all reduced as in the first embodiment described above. For this reason, by adjusting the arrangement position of each of the magnetoelectric transducers 25a to 25j and the direction of the sensitivity axis, the measurement sensitivity can be kept constant as a whole regardless of the bending rate of the measured current CB.

Second Embodiment
In the above-described embodiment, the case where the four first magnetoelectric conversion elements 25a, 25e, 25f, and 25j and the six second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are used is exemplified. In the embodiment, a case where four first magnetoelectric conversion elements and four second magnetoelectric conversion elements are used is illustrated.

  FIG. 11 is a view for explaining the arrangement of the first magnetoelectric conversion elements 125a, 125b, 125c, and 125d and the second magnetoelectric conversion elements 125e, 125f, 125g, and 125h on the substrate 116 in the second embodiment of the present invention. FIG. FIG. 12 is a diagram for explaining the arrangement of the magnetoelectric conversion elements on the substrate 116 of the current sensor 301 shown in FIG.

  As shown in FIGS. 11 and 12, in the current sensor 201, the first magnetoelectric conversion elements 125a, 125b, 125c, and 125d are provided on the first surface 116a of the substrate 116 close to the second current path portion CB2. The second magnetoelectric conversion elements 125e, 125f, 125g, and 125h are provided on the second surface 116b of the substrate 116 that is far from the second current path portion CB2.

  The first magnetoelectric conversion elements 125a, 125b, 125c, and 125d and the second magnetoelectric conversion elements 125e, 125f, 125g, and 125h are virtual centroids PP of the cross section of the first current path portion CB1 of the measured current path CB. It is arranged at the apex on the regular rectangle LL.

The first magnetoelectric conversion elements 125a and 125d have a first sensitivity axis in the X2 direction, and the first magnetoelectric conversion elements 125b and 125c have a first sensitivity axis in the X1 direction.
The second magnetoelectric conversion elements 125e and 125f have a second sensitivity axis in the Y1 direction, and the first magnetoelectric conversion elements 125g and 125h have a second sensitivity axis in the Y2 direction.

As in the first embodiment, in the current sensor 301, the current path CB to be measured includes the second current path portion CB2 that is inclined at right angles to the first current path portion CB1, and therefore, the second current path portion CB2 Is smaller than the first current path portion CB1 and the component parallel to the sensitivity axis (Y1-Y2 direction) of the magnetic second magnetoelectric transducer generated by the current flowing through the measured current path CB is smaller. Further, in the vicinity of the first current path portion CB1, parallel to the sensitivity axis of the magnetic second magnetoelectric transducer generated by the current flowing through the first current path portion CB1 as the distance to the second current path portion CB2 increases. Ingredients become larger.
On the other hand, around the second current path portion CB2, parallel to the sensitivity axis (X1-X2 direction) of the magnetic first magnetoelectric transducer generated by the current flowing through the second current path portion CB2 as it approaches the second current path portion CB2. Ingredients become larger.

  In the current sensor 301, the first magnetoelectric conversion elements 125 a and 125 d are provided on the open ends 116 c and 116 d side of the two arms 1161 and 1162 of the first surface 116 a of the substrate 116. Therefore, the component parallel to the sensitivity axis of the first magnetoelectric conversion element (X1-X2 direction) generated by the current flowing through the second current path portion CB2 at the position of the first magnetoelectric conversion elements 125a and 125d becomes large.

The second magnetoelectric conversion elements 125e, 125f, 125g, and 125h are provided on the second surface 116b of the substrate 116 opposite to the second current path portion CB2. Therefore, the component parallel to the sensitivity axis of the magnetic second magnetoelectric conversion element (Y1-Y2 direction) generated by the current flowing through the first current path portion CB1 at the position of the second magnetoelectric conversion elements 125e, 125f, 125g, and 125h is large. Become.
As a result, the sensitivity to magnetism as a whole can be increased by the current flowing through the measured current path CB, and the measurement accuracy can be increased.
As a result, it is possible to suppress a change in measurement sensitivity when the measured current path is a straight line and when the measured current path is bent like the measured current path CB.

In the current sensor 301, when the current flowing through the measured current path CB shown in FIG. 1 is measured, the sensitivity of the first magnetoelectric conversion elements 125a and 125d is increased, and the sensitivity of the first magnetoelectric conversion elements 125b and 125c is decreased. In addition, the second magnetoelectric conversion elements 125e, 125f, 125g, and 125h all have reduced sensitivity, but the change in measurement sensitivity can be suppressed as a whole.
On the other hand, in the current sensor 201, when the measured current path CB is linear, the sensitivity of the first magnetoelectric conversion elements 125a, 125b, 125c, and 125d and the second magnetoelectric conversion elements 125e, 125f, 125g, and 125h is approximately. Be the same.

As described above, the current sensor 301 can provide the same effect as that of the current sensor 201 of the first embodiment.
FIG. 13 is a diagram illustrating the relationship between the distance H between the current sensor 301 and the like and the second current path portion CB2 and the magnetic field detection sensitivity. The horizontal axis of FIG. The vertical axis represents the sensitivity when the magnetic field detection sensitivity is 100% when the measured current path CB is a straight line.
As shown in FIG. 13, the magnetic field detection sensitivity changes most when the current sensor 301 shown in FIGS. 11 and 12 is the smallest (G11), and changes most when all the magnetoelectric transducers are arranged on the second surface 116a. Large (G13), the amount of change between them is when all the magnetoelectric transducers are arranged on the second surface 116b (G12).

  Further, according to the current sensor 301, the overall configuration can be reduced. Further, since the temperatures of the paired magnetoelectric conversion elements are equal, even if the magnetoelectric conversion elements have temperature characteristics, it is possible to prevent the measurement accuracy from deteriorating.

The present invention is not limited to the embodiment described above.
That is, those skilled in the art may make various modifications, combinations, subcombinations, and alternatives regarding the components of the above-described embodiments within the technical scope of the present invention or an equivalent scope thereof.
In the embodiment described above, the number of magnetoelectric conversion elements is not particularly limited as long as it is 10 or more.

  In the above-described embodiment, the case where the angle between the first current path portion CB1 and the second current path portion CB2 of the measured current path CB is a right angle is illustrated. When the angle between the first current path portion CB1 and the second current path portion CB2 of the measured current path CB is not a right angle, the first magnetoelectric transducers 25a, 25e, 25f, and 25j are in the first current direction (Z-axis direction). And a magnetic field in a direction (X direction) perpendicular to a direction (Y direction) in which the second current is projected onto a plane (XY plane) perpendicular to the first current direction. That is, the first magnetoelectric conversion elements 25a, 25e, 25f, and 25j are arranged with their sensitivity axes directed in a direction less than 45 degrees from the X direction. The second magnetoelectric transducers 25b, 25c, 25d, 25g, 25h, and 25i detect a magnetic field in a direction (Y direction) obtained by projecting the second current direction onto a plane (XY plane) perpendicular to the first current direction. Arrange as follows. That is, the second magnetoelectric conversion elements 25b, 25c, 25d, 25g, 25h, and 25i are arranged with their sensitivity axes oriented in a direction less than 45 degrees from the Y direction.

  Moreover, you may arrange | position a magnetoelectric conversion element in the position and direction different from embodiment mentioned above. However, in each magnetoelectric conversion element, another magnetoelectric conversion element is arranged at a line-symmetrical position with respect to the first virtual line IL1. In addition, each magnetoelectric conversion element is provided with another magnetoelectric conversion element at a line-symmetrical position with respect to the second virtual line IL2. (However, the magnetoelectric conversion element arranged on the second imaginary line IL2 is excluded.) Also, the magnetoelectric conversion elements that are point-symmetric (that is, two-fold rotationally symmetric positions) with respect to the center of gravity PP of the current CB to be measured. The sensitivity axes of are parallel. If this condition is greatly deviated, the measurement error increases.

In addition, if the number of the 1st magnetoelectric conversion element and the 2nd magnetoelectric conversion element is an even number, it is arbitrary. Further, the distance between the magnetoelectric conversion elements is not particularly limited.
In the above-described embodiment, the case where the magnetoelectric conversion elements having the same characteristics are used is exemplified. However, the component corresponding to the magnetic field of the current path CB to be measured is accumulated and validated in the arithmetic circuit in the subsequent stage, and the adjacent current paths A magnetoelectric conversion element having two or more characteristics may be used as long as the component corresponding to the magnetic field can be canceled.

In the above-described embodiment, the GMR element is preferably used as the magnetoelectric conversion element. However, any magnetic sensing element capable of detecting the direction of magnetism may be used. An MR (Magneto Resistive) element, an AMR (Anisotropic Magneto Resistive) element, TMR (Tunnel Magneto Resistive)
It may be an element, a Hall element, or the like. However, in the case of a Hall element or the like, since it differs from the sensitivity axis of the GMR element or MR element, it is necessary to devise mounting in accordance with the sensitivity axis of the Hall element to be used.

101, 201, 301 ... current sensor 11 ... casing 13 ... connector 16, 116 ... substrate 16a, 116a ... first surface 16b, 116b ... second surface 16c, 16d, 116c, 116d ... tip 161, 162, 1161, 1162 ... arms 25a-25j, 125a-125h
31 ... Case L, LL ... Rectangle IL1 ... First imaginary line IL2 ... Second imaginary line L1, L2, ... Long side L3 ... Short side

Claims (17)

A current sensor that uses magnetism generated by a current flowing through a current path to be measured including a first current path portion and a second current path portion bent with respect to the first current path portion,
A plurality of first magnetoelectric transducers arranged to surround the first current path portion;
A plurality of second magnetoelectric transducers arranged in two rows so as to sandwich the first current path portion,
In the first current path portion, a current flows in a first current direction,
In the second current path portion, current flows in the second current direction,
The plurality of first magnetoelectric transducers are arranged at point-symmetric positions with a virtual point at which the center of the first current path portion is arranged as a symmetry point,
The plurality of second magnetoelectric transducers are arranged at point-symmetric positions with the virtual point as a symmetry point,
The second magnetoelectric transducer detects a magnetic field in a direction in which the second current direction is projected onto a plane perpendicular to the first current direction;
The first magnetoelectric transducer detects a magnetic field in a direction perpendicular to the first current direction and the second current direction projected onto a plane perpendicular to the first current direction;
In the second current direction, the first magnetoelectric transducer is positioned outside the second magnetoelectric transducer,
The first magnetoelectric conversion element at a position close to the second current path portion is located on the second current path portion side in a direction parallel to the first current direction with respect to the second magnetoelectric conversion element. A current sensor. The first magnetoelectric transducer is perpendicular to the first current direction and has a sensitivity axis in a direction less than 45 ° with respect to a direction perpendicular to the second current direction,
2. The current sensor according to claim 1, wherein the second magnetoelectric conversion element has a sensitivity axis in a direction of less than 45 ° with respect to a direction parallel to the second current direction.   The column formed by the plurality of second magnetoelectric transducers is a straight line, and the direction of the column is parallel to the direction in which the second current direction is projected on a plane perpendicular to the first current direction. The current sensor according to claim 1. The direction of the sensitivity axis of the first magnetoelectric transducer is a direction perpendicular to the first current direction and perpendicular to the direction in which the second current direction is projected onto a plane perpendicular to the first current direction,
4. The current sensor according to claim 3, wherein the direction of the sensitivity axis of the second magnetoelectric transducer is a direction in which the second current direction is projected onto a plane perpendicular to the first current direction. 5.   The current sensor according to claim 1, wherein the row formed by the plurality of second magnetoelectric conversion elements is a curve.   6. The current according to claim 5, wherein directions of sensitivity axes of the first magnetoelectric conversion element and the second magnetoelectric conversion element are directions of an induced magnetic field generated from a current flowing through the first current path portion. Sensor.   The current sensor according to claim 3, wherein the first magnetoelectric conversion element is located at an end of the row. A substrate provided with the first magnetoelectric conversion element and the second magnetoelectric conversion element;
The first magnetoelectric conversion element at a position close to the second current path portion is provided on the first surface of the substrate on the second current path portion side,
The current sensor according to claim 1, wherein the second magnetoelectric conversion element is provided on a second surface of the substrate opposite to the second current path portion side. The current sensor according to claim 1, wherein the first current path portion and the second current path portion are at right angles. A substrate,
A plurality of first magnetoelectric transducers provided on the substrate;
A plurality of second magnetoelectric transducers provided on the substrate,
The substrate has two parallel arm portions and a root portion connecting the two arm portions,
All the second magnetoelectric transducers are arranged side by side in the direction in which the arms extend,
All the first magnetoelectric transducers are located at the end of the row of the plurality of second magnetoelectric transducers,
The first magnetoelectric transducer detects a magnetic field in a direction orthogonal to a direction in which the arm portion extends,
The second magnetoelectric conversion element detects a magnetic field in a direction in which the arm portion extends,
Among the first magnetoelectric conversion elements, the two first magnetoelectric conversion elements provided on the most distal end side of the arm portion are provided on the first surface of the substrate,
All said 2nd magnetoelectric conversion elements are provided in the 2nd surface on the opposite side to the said 1st surface, The current sensor characterized by the above-mentioned. The direction of the sensitivity axis of the first magnetoelectric transducer is perpendicular to the first current direction and perpendicular to the second current direction,
The current sensor according to claim 10, wherein a direction of a sensitivity axis of the second magnetoelectric conversion element is a direction parallel to the second current direction.   10. The current according to claim 9, wherein directions of sensitivity axes of the first magnetoelectric conversion element and the second magnetoelectric conversion element are directions of an induced magnetic field generated from a current flowing through the first current path portion. Sensor. All the first magnetoelectric transducers are provided on the first surface of the substrate,
The current sensor according to claim 7, wherein all the second magnetoelectric conversion elements are formed on the second surface opposite to the first surface of the substrate. Four first magnetoelectric transducers;
The current sensor according to claim 1, comprising six or more second magnetoelectric conversion elements. The first magnetoelectric conversion element and the second magnetoelectric conversion element located at the end of the first magnetoelectric conversion element and the second magnetoelectric conversion element are provided at positions opposite to each other on the opposite side of the substrate. The current sensor according to any one of -12. Four first magnetoelectric transducers;
The current sensor according to claim 1, comprising four second magnetoelectric conversion elements. The first magnetoelectric transducer is provided at four vertices of a virtual rectangle where the measured current path is located,
The second magnetoelectric transducer is provided on the long side of the rectangle so as to be symmetric with respect to an imaginary line passing through the center of gravity of the rectangle and parallel to the long side of the rectangle and point-symmetric to the center of gravity. The first magnetoelectric transducer detects a magnetic field parallel to the short side of the rectangle,
The second magnetoelectric transducer detects a magnetic field parallel to the long side,
The direction of the detectable magnetic field between the first magnetoelectric transducers in a point-symmetric position with respect to the center of gravity is the same or reverse,
The direction of the detectable magnetic field between the second magnetoelectric transducers in a point-symmetrical position with respect to the center of gravity is the same or opposite. Claims 1, 3, 4, 7, 8, 9, 10, 11, 13, The current sensor according to any one of 14.

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