JP2001083184A - Current sensor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow attaching/detaching of a part of a magnetic yoke and to prevent degradation in characteristics which follows it. SOLUTION: A current sensor device comprises an annular magnetic yoke 2 which, so provided as to enclose a current carrier 1, forms a magnetic path J for the magnetic flux, generated by the current which is to be measured and flows the current carrier 1, to pass, with a gap G provided to a part of it, and a magnetic sensor element 3 provided in the gap G of the magnetic yoke 2. The magnetic yoke 2 comprises a magnetic body 2M1, non-magnetic body 2N1, magnetic body 2M2, non-magnetic body 2N2, and non-magnetic body 2M3 arrayed along the magnetic path J. The magnetic yoke 2 is separated at the border part between the magnetic body 2M2 and the non-magnetic body 2N1 as well as the border part between the magnetic body 2M2, and the non- magnetic body 2N2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current sensor device for measuring a relatively large current in a non-contact manner.

[0002]

2. Description of the Related Art Many types of magnetic sensor devices and non-contact type current sensor devices using the same have been developed since they are industrially useful. However, its application is special and has not been a very large market. Therefore, at present, development in terms of cost has not been sufficiently performed.

However, recently, electric vehicles and photovoltaic power generation have been actively developed due to waste gas regulations caused by environmental problems. Several kW for electric vehicles and solar power
In order to handle DC power of up to several tens of kW, a non-contact type current sensor device that measures DC current of several tens to several hundreds of A is indispensable. Because such a current sensor device has a huge demand, it needs to be extremely inexpensive in addition to its characteristics.
This will hinder the spread of electric vehicles and solar power generation. Thus, the current sensor device has good characteristics,
It is socially demanded that it be inexpensive.

When a current is measured in a non-contact manner, an AC component can be easily measured by the principle of a transformer. However, since the DC component cannot be measured by this method, a method of measuring a magnetic field generated by a current with a magnetic sensor is employed. As a magnetic sensor for this purpose, a Hall element is often used, and there are also examples of using a magnetoresistive element or a fluxgate element.

A current sensor device using a Hall element which has been most developed in the prior art has, for example, the following problems. (1) The sensitivity is low. (2) The sensitivity variation is large. (3) The temperature characteristics are poor. (4) The processing of the offset voltage is troublesome.

[0006] In addition to the above problems, the magnetoresistive effect element has a problem that linearity is poor.

Regarding the problem of the Hall element, a solution has been developed to some extent. As one of the solutions, for example, sensitivity variations, temperature characteristics, and linearity are improved by inverting a magnetic field proportional to the element output and adding the element to the element, and applying negative feedback so that the element output is always constant. There is a method, the so-called negative feedback method.

However, when the negative feedback method is used, it is necessary to apply a reverse magnetic field having the same magnitude as the detected magnetic field to the element. Therefore, in the case of detecting a current of several hundreds of amperes (A), such as an electric vehicle or a photovoltaic power generation, the feedback current is several A even if the number of turns of the feedback magnetic field generating coil is 100 turns. Therefore, if the current sensor device is actually configured by this method, it becomes extremely large and expensive.

If the magnetic sensor element has high sensitivity, it is conceivable to add only a part of the magnetic field to be detected (for example, 1/100) to the element to reduce the feedback current. This is difficult because of the low sensitivity.

The flux gate element has been developed mainly for detecting a small magnetic field, and the technology for detecting a large current has not been developed much. However, the flux gate element has a feature of high sensitivity with a simple configuration, and is effective as a magnetic detection unit of a current sensor device for a large current depending on the device.

Here, the operation principle of the simplest flux gate device will be described with reference to FIG. FIG. 9 is a characteristic diagram showing a relationship between the inductance of the coil wound around the magnetic core and the coil current. Since the magnetic core has magnetic saturation characteristics, when the coil current increases, the effective magnetic permeability of the magnetic core decreases, and the inductance of the coil decreases. Therefore, if the bias magnetic field B is applied to the magnetic core by a magnet or the like, when the external magnetic field H ₀ is superimposed on the bias magnetic field, the external magnetic field H ₀
The magnitude of _zero can be measured as a change in the inductance of the coil. This is the simplest principle of operation of the fluxgate device. In FIG. 9, both the bias magnetic field B and the external magnetic field H ₀ are represented by magnitudes converted into coil currents.

However, in this method, since the position of the bias point B changes depending on the strength of the magnetic field generated by the magnet, the positional relationship between the magnet and the magnetic core, etc., the inductance value when the external magnetic field is zero is adjusted to a constant value. It is necessary to keep. However, it is extremely difficult to compensate for the instability of this value against a temperature change or other disturbance. Therefore, the above method is not suitable for practical use.

By the way, the effect of hysteresis is usually very small in the case of a rod-shaped magnetic core because it has an open magnetic path. Therefore, if the hysteresis of the magnetic core is ignored, the saturation characteristic of the magnetic core does not depend on the direction of the coil current.Therefore, the change characteristic of the inductance between when the coil current is made positive and when it is made negative is Are identical. E.g., P in FIG. 9 ₊ a point and P
_The point represents a positive coil current and a negative coil current having the same absolute value. In the vicinity of these points, the change characteristic of the inductance with respect to the change of the absolute value of the coil current is the same. Therefore, if an alternating current is applied to the coil such that the magnetic core enters the saturation region at the peak, and the difference of the decrease in the inductance at each of the positive and negative peak values of the current is measured, the external magnetic field is zero when the external magnetic field is zero. The difference is always zero. This does not change even if the characteristics of the magnetic core change due to a temperature change or a disturbance. In the present application, the saturation region of the magnetic core refers to a region where the absolute value of the magnetic field is larger than the absolute value of the magnetic field when the magnetic permeability of the magnetic core becomes the maximum magnetic permeability.

On the other hand, when an external magnetic field is applied to the magnetic core,
For example, as shown in FIG. 9, when an external magnetic field H ₀ is applied in the positive direction of the current, the inductance value decreases at the positive peak of the current (for example, the Q ₊ point in FIG. 9), and the negative peak decreases. (e.g. Q in FIG. 9 _- point), the inductance value because increases, the difference has a value other than zero. Since the difference between the inductance values depends on the external magnetic field, the external magnetic field can be measured by measuring the difference between the inductance values.

As described above, the method of applying an alternating current to the coil so that the magnetic core enters the saturation region at the peak time and measuring the difference of the decrease in the inductance at each of the positive and negative peak values of the current is disclosed in the present application. , Is referred to as a large amplitude excitation method.

The large-amplitude excitation method is very excellent because it can remove the effects of temperature changes and disturbances. However, it is not so easy to supply the coil with an alternating current sufficient to saturate the magnetic core. For this reason, conventionally, the application has been limited to a magnetic sensor device for detecting a small magnetic field using an amorphous magnetic core or the like having a small saturation magnetic field.

In order to detect a direct current in a non-contact manner, a method of detecting a magnetic field generated by the current with a magnetic sensor element is generally adopted. In this method, for example, a magnetic yoke having an air gap is provided around a current path, a magnetic sensor element is installed in the air gap, and a magnetic field in the air gap is measured by the magnetic sensor element. Assuming that the current value is I and the length of the gap is g, the magnetic field strength H in the gap is H = I / g. Therefore, the current value I can be obtained by measuring the magnetic field H with the magnetic sensor element.

Here, a case where a flux gate element is used as the magnetic sensor element will be considered. The flux gate element has a feature that the length in the magnetic field application direction is relatively long. Therefore, the gap length g is relatively long. Actually, the length of the flux gate element in the magnetic field application direction is
Even a short one is about 1 to 5 mm. Further, since the flux gate element has high sensitivity and does not require a very large magnetic field, the gap length may be long. That is, in the current sensor device using the flux gate element, the gap length of the magnetic yoke is longer than when using another magnetic sensor element such as a Hall element. When actually designing, the air gap length is 10 to 2 in a 500 A class current sensor device.
0 mm.

[0019]

By the way, in the conventional current sensor device using the Hall element, since the sensitivity of the Hall element is low, the length of the gap for inserting the Hall element is 1-2.
mm, and the magnetic yoke constitutes a closed magnetic circuit as much as possible except for this gap. Therefore, the current carrier through which the current to be measured flows must pass through the hole of the annular body formed by the magnetic yoke and the Hall element.

The operation of passing the current carrier through the hole of the annular body is simple when the current to be measured is small and the current carrier is thin and soft. However, when a large current of several hundred A flows through the current carrier as in an electric vehicle, the current carrier has a thick rod shape, and it is very difficult to pass the current carrier through the hole of the annular body. Therefore, in such a case, usually, a structure is prepared in which the current carrier is previously passed through the hole of the annular body of the current sensor device, and the structure is installed at a predetermined place. I have.

However, in general, the current carrier for flowing a large current as described above is not an isotropic shape such as a round bar, but has an extended end so that it can be screwed, or a connecting member. Are attached by welding or have bent parts. Therefore, in many cases, a hole having a size larger than the outer shape of the current carrier is required as the hole of the annular body for passing the current carrier.

In a current sensor device having a large annular body hole,
There are problems that the shape becomes larger than necessary and that the measurement error due to the fluctuation of the position of the current carrier in the hole increases.

In the conventional current sensor device using a Hall element, the magnetic path is quasi-closed and easily saturates. Therefore, the magnetic yoke is made of a material having a high saturation magnetic flux density.
For example, a metal magnetic material is required. However, when a magnetic yoke made of a metallic magnetic material is used, eddy current loss in the magnetic yoke increases, and thus there is a problem that the high-frequency characteristics of the current sensor device deteriorate.

In the current sensor device, if a part of the magnetic path is detachable, the operation of passing the current carrier through the hole of the annular body becomes easy. Note that Japanese Patent Application Laid-Open No. 8-1532
No. 2 discloses a current sensor device in which an annular magnetic core (magnetic yoke) is divided into two at a butting portion and is configured to be freely opened and closed.

However, a major problem in the conventional current sensor device using the Hall element is that it is difficult to make a part of the magnetic path detachable without deteriorating the characteristics. Hereinafter, this will be described in detail with reference to FIGS.

As described above, in the conventional current sensor device using the Hall element, since the sensitivity of the Hall element is low, the magnetic yoke forms a closed magnetic path as much as possible except for the gap for inserting the Hall element. I have to. FIG. 10 is a cross-sectional view illustrating a main part of an example of a current sensor device using a Hall element. This current sensor device comprises a current carrier 20
The magnetic yoke 202 includes a ring-shaped magnetic yoke 202 that is disposed so as to surround the magnetic element 1 and partially has a gap G, and a Hall element 203 that is disposed in the gap G of the magnetic yoke 202.

In a conventional current sensor device using a Hall element, a metal magnetic material is generally used as the material of the magnetic yoke 202 because it needs to have a high saturation magnetic flux density. Also, to reduce eddy current loss,
As the magnetic yoke 202, for example, a magnetic yoke having a structure in which a thin plate made of a metallic magnetic material such as a silicon steel plate and an insulating material is applied is laminated.

Here, in order to make a part of the magnetic path, that is, a part of the magnetic yoke 202 detachable, as shown in FIG.
A and 205B are considered. In this case, the magnetic yoke 202 includes two magnetic yoke body portions 202A, 202A.
02B and a removable portion 202C.

As described above, the separation portion 2 is
05A and 205B, the magnetic yoke body 2
After the detachable portion 202C is separated from the second detachable portions 202C, the two detachable portions 20C are separated from each other.
A minute gap is formed between 5A and 205B. The width of the gap changes every time the removable portion 202C is detached. The width of the gap in the separation portions 205A and 205B can be equivalently regarded as an increase in the length of the gap G into which the Hall element is inserted.

Since the length of the gap G for inserting the Hall element 203 is generally about 2 mm, for example, a measurement error due to a change in the width of the gap caused by repeated attachment and detachment of the detachable portion 202C is reduced to within 1%. In order to fit, the variation in the width of the gap must be suppressed within 20 μm, which is 1/100 of 2 mm.

However, when the magnetic yoke 202 having the above-mentioned laminated structure is used, the magnetic yoke 20
2 are cut to form the separation portions 205A and 205B, the respective portions 20 forming the separation portions 205A and 205B are formed.
The end faces of 2A, 202B, 202C are jagged. Polishing this end face destroys the insulation between the laminated thin plates and increases the eddy current loss,
Difficult to adopt. Therefore, the width of the gap between the separation portions 205A and 205B is practically required to be at least about 100 μm.

Here, the length of the gap G for inserting the Hall element 203 is 2 mm, and the separation portions 205A, 205A
Assuming that the width of each gap in 05B is 100 μm, a magnetic field equivalent to the case where the length of the gap G is 2.2 mm is applied to the Hall element 203 on average.

On the end surfaces of the portions 202A, 202B, and 202C in the separation portions 205A and 205B, irregularities are generated by exposing the cross section of the laminated thin plate material. If the height difference between the irregularities is about 50 μm, the convex portions on the two opposing end surfaces face each other, and there may be no gap at that portion. When this occurs on one of the two separation portions 205A and 205B, a magnetic field equivalent to that when the length of the gap G is 2.1 mm is applied to the Hall element 203. . This causes a measurement error of about 5% in the current sensor device.

Further, since the cross-sectional area of the magnetic path is small at the portion where the two convex portions face each other, magnetic saturation easily occurs at that portion. When magnetic saturation occurs, the equivalent length of the gap G increases, and the magnetic field applied to the Hall element 203 decreases. This means that the linearity of the measured value of the current sensor device is deteriorated by an increase in the measured current value.

As described above, in the conventional current sensor device using the Hall element, it was extremely difficult to make a part of the magnetic path detachable without deteriorating the characteristics.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a current sensor device which enables a part of a magnetic yoke to be attached and detached and prevents deterioration of characteristics due to attachment and detachment. Is to do.

[0037]

A first current sensor device according to the present invention is arranged so as to surround a current carrier through which a current to be measured flows, has a gap in a part thereof, and measures a current to flow through the current carrier. An annular magnetic yoke that forms a magnetic path through which a magnetic flux generated by the magnetic flux sensor passes, and a magnetic sensor element that is arranged in the gap of the magnetic yoke and detects a magnetic field in the gap generated by the measured current flowing through the current carrier. ,
The magnetic yoke includes a magnetic body portion made of a magnetic material and a non-magnetic material portion made of a non-magnetic material, and is arranged along a magnetic path, and at least one boundary between the magnetic body portion and the non-magnetic material portion. The part can be separated.

In the first current sensor device of the present invention, since the magnetic yoke includes the magnetic portion and the non-magnetic portion and can be separated at the boundary between the magnetic portion and the non-magnetic portion. A part of the magnetic yoke can be made detachable.

In the first current sensor device of the present invention,
The magnetic yoke may have a main body part constituting a main part and a detachable part which is disposed at a boundary part where at least one end is separable and is detachable from the main body part. In this case, the detachable portion may include a magnetic material portion, or may include a non-magnetic material portion,
It may include a magnetic part and a non-magnetic part.

In the first current sensor device according to the present invention, the detachable portion has a long portion along the magnetic path of the magnetic portion and the non-magnetic portion due to a change in the position in the direction along the magnetic path. It may be arranged at a position where the sum of the values does not change.

Further, the first current sensor device of the present invention comprises:
Further, a positioning means for positioning the current carrier with respect to the magnetic yoke may be provided.

Further, in the first current sensor device of the present invention, the magnetic sensor element may be a flux gate magnetic sensor element.

In the first current sensor device of the present invention, the magnetic body may be made of ferrite.

Further, in the first current sensor device of the present invention, the length of the non-magnetic portion along the magnetic path may be 0.1 mm or more.

The second current sensor device of the present invention is arranged so as to surround the current carrier through which the current to be measured flows, has a gap in a part thereof, and passes the magnetic flux generated by the current to be measured flowing through the current carrier. An annular magnetic yoke forming a magnetic path to be formed, and a magnetic sensor element disposed in the gap of the magnetic yoke and detecting a magnetic field in the gap generated by the measured current flowing through the current carrier. A first magnetic body portion made of a first magnetic body and a second magnetic body portion made of a second magnetic body having a lower magnetic permeability than the first magnetic body, arranged along the road; , At least one boundary portion between the first magnetic body and the second magnetic body.

In the second current sensor device according to the present invention, the magnetic yoke includes the first magnetic body and the second magnetic body, and the magnetic yoke is provided between the first magnetic body and the second magnetic body. Can be detached at the boundary of the magnetic yoke, so that a part of the magnetic yoke can be detached.

In the second current sensor device of the present invention,
The magnetic yoke may have a main body part constituting a main part and a detachable part which is disposed at a boundary part where at least one end is separable and is detachable from the main body part.

[0048]

Embodiments of the present invention will be described below in detail with reference to the drawings. [First Embodiment] FIG. 1 is a sectional view showing a main part of a current sensor device according to a first embodiment of the present invention. As shown in FIG. 1, the current sensor device according to the present embodiment is arranged so as to surround a current carrier 1 through which a current to be measured flows, has a gap G in a part thereof, and receives a current flowing through the current carrier 1. An annular magnetic yoke 2 that forms a magnetic path J through which a magnetic flux generated by the measurement current passes, and an annular magnetic yoke 2 that is arranged in the gap G of the magnetic yoke 2 and that is generated by the measured current flowing through the current carrier 1. A magnetic sensor element 3 for detecting a magnetic field. The overall sectional shape of the magnetic yoke 2 is rectangular. The magnetic sensor element 3 is, for example, a flux gate magnetic sensor element.

The magnetic yoke 2 includes magnetic portions 2M ₁ , 2M ₂ and 2M _{3 made} of a magnetic material, and non-magnetic portions 2N ₁ and 2N _{2 made of a} non-magnetic material. When viewed clockwise from the left end of the gap G in FIG. 1 as a starting point, the magnetic portion 2M ₁ , the non-magnetic portion 2N ₁ , the magnetic portion 2M ₂ , the non-magnetic portion 2N ₂ , and the magnetic portion It is arranged along the path J in the order of 2M _3.

In FIG. 1, the magnetic portion 2M ₁ has an L-shaped cross-section, and defines a part of the left side of the lower side and a part of the lower side of the left side of the entire magnetic yoke 2. Is formed. Magnetic material portion 2M ₃ has a symmetrical cross-sectional shape of the magnetic body 2M _1, and part of the lower right portion and the right side portion of the lower side portion of the total of the magnetic yoke 2 Is formed. Magnetic material portion 2M ₃ consists of two parts extending from both ends of the partial and horizontal directions of extending portions downwardly, part and right part of the upper of the upper side portion and left side portion of the total of the magnetic yoke 2 And an upper part.

The non-magnetic part 2N ₁ is disposed between the upper end of the magnetic part 2M ₁ and the lower end on the left side of the magnetic part 2M ₂ ;
The magnetic yoke 2 forms a part of the left side portion of the whole. The non-magnetic part 2N ₂ is a magnetic part 2M ₃
It is disposed between the upper portion and the right side of the lower end portion of the magnetic body portion 2M ₂ of, so as to form a part of the right side portion of the total of the magnetic yoke 2.

[0052] In this embodiment, the magnetic yoke 2, 2 of the boundary portion between the magnetic body portion 2M ₂ and the boundary portion between the non-magnetic portion 2N _1, a magnetic unit 2M ₂ and the non-magnetic portion 2N ₂ It can be separated at some points.

The magnetic part 2M ₁ , the non-magnetic part 2N ₁ , the non-magnetic part 2N ₂ and the magnetic part 2M ₃ constitute a main part constituting the main part of the magnetic yoke 2, and the magnetic part 2M ₂ It is a detachable portion 2D detachable from the portion. Thus, in this embodiment, the removable portion 2D comprises a magnetic portion 2M _2.

The magnetic portions 2M ₁ , 2M ₂ and 2M ₃ are formed of a magnetic material having a high magnetic permeability, for example, ferrite.

The nonmagnetic portions 2N ₁ and 2N ₂ can be formed using a ceramic material, a plastic material, a rubber material, or the like. Further, the nonmagnetic portions 2N ₁ and 2N ₂ may be formed of air. In this case, a predetermined gap may be provided between the magnetic parts 2M ₁ and 2M _{2 and} between the magnetic parts 2M ₃ and 2M ₂ . The length of the nonmagnetic portions 2N ₁ and 2N ₂ along the magnetic path J is preferably practically 0.1 mm or more.

FIG. 2 is a block diagram showing an example of a circuit configuration of the current sensor device according to the present embodiment. In this example, the current sensor device includes the magnetic sensor element 3 disposed in the gap G of the magnetic yoke 2 as shown in FIG. The magnetic sensor element 3 includes a magnetic core 101 and the magnetic core 1.
01 and at least one sensor coil 102 wound around at least one coil. The current sensor device further includes an AC current supply unit 103 that supplies an AC drive current to the sensor coil 102 such that one end is connected to one end of the sensor coil 102 and the other end is grounded, and the magnetic core 101 reaches a saturation region. And an inductance element 104 connected in series with the sensor coil 102 for detecting a change in the inductance value of the sensor coil 102. One end of the inductance element 104 is connected to the other end of the sensor coil 102, and the other end is grounded.

The current sensor device shown in FIG. 2 is further connected to a connection point between the sensor coil 102 and the inductance element 104 and differentiates a voltage generated at both ends of the inductance element 104; 1
A positive peak hold circuit 106 for holding the positive peak value of the output signal 05 and a negative peak hold circuit 107 for holding the negative peak value of the output signal of the differentiating circuit 105
An adder circuit 108 for adding the value held by the positive peak hold circuit 106 and the value held by the negative peak hold circuit 107;
And an output terminal 109 for outputting the output signal.

In the current sensor device shown in FIG. 2, the excitation current of the sensor coil 102 supplied from the AC current supply section 103 is applied to the inductance element 104 and the differentiation circuit 1.
05, two spike-shaped voltage signals having opposite polarities, representing the positive and negative peak values of the excitation current. Each peak value of the positive and negative spike-shaped voltage signals is held by a positive peak hold circuit 106 and a negative peak hold circuit 107, added by an adder circuit 108, and output as an output signal from an output terminal 109.

Next, the operation of the current sensor device according to this embodiment will be described. In FIG. 1, a magnetic flux generated by a measured current flowing through a current carrier 1 in a direction perpendicular to the plane of FIG. 1 is converged by a magnetic yoke 2,
It passes through the magnetic yoke 2. Then, the magnetic field in the air gap G is measured by the magnetic sensor element 3 arranged in the air gap G of the magnetic yoke 2 and the circuit shown in FIG. .

[0060] In this embodiment, the magnetic yoke 2, 2 of the boundary portion between the magnetic body portion 2M ₂ and the boundary portion between the non-magnetic portion 2N _1, a magnetic unit 2M ₂ and the non-magnetic portion 2N ₂ It can be separated at some points. Therefore, the detachable portion 2D which is a part of the magnetic yoke 2 is detachable from the main body. Therefore, according to the present embodiment, the current carrier 1 can be introduced into the hole of the magnetic yoke 2 through the portion opened by separating the detachable portion 2D from the main body portion. The work of passing the current carrier 1 through the hole is facilitated. Further, according to the present embodiment, the current sensor device can be mounted on the current carrier 1 even after the placement of the current carrier 1 is completed.

In a conventional current sensor device using a Hall element as the magnetic sensor element, the length of the gap for inserting the Hall element is usually about 2 mm. Therefore, in the case where a part of the magnetic yoke is detachable as shown in FIG. 11, if a gap of about 100 μm is formed in the separation part, a measurement error due to a change in the width of the gap due to repetition of detachment of the detachable part. Becomes larger.

On the other hand, when a fluxgate magnetic sensor element is used as the magnetic sensor element 3 as in the present embodiment, the length of the gap portion of the magnetic yoke must be increased because the sensitivity of the magnetic sensor element 3 is high. Can be. For example,
Assuming that the length of the gap of the magnetic yoke is 15 mm, when the magnetomotive force is 500 A, the magnetic flux density in the gap is about 45 mm.
mT, which is an appropriate value for the operation of the fluxgate magnetic sensor element. However, since the length of the fluxgate magnetic sensor element is about 3 mm, it is 15 mm.
When the fluxgate magnetic sensor element is inserted into the gap having the length of, the length of the gap becomes much larger than the length of the magnetic sensor element. In this case, a noise magnetic field is likely to be applied to the magnetic sensor element through the gap, and the magnetic field generated in the gap due to the current to be measured reaches far and becomes a noise source in other parts.

Therefore, in this embodiment, the magnetic yoke 2
Are provided with non-magnetic portions 2N ₁ and 2N _{2 serving} as voids, separately from the void G into which the magnetic sensor element 3 is inserted. Thus, the gap G into which the magnetic sensor element 3 is inserted
The length of the plurality of gaps of the magnetic yoke 2 can be set to a value that is just suitable for the operation of the fluxgate magnetic sensor element without making the length of the magnetic yoke 2 too large. When the negative feedback method is used, the magnetic sensor element 3 always operates in a state where the magnetic flux is zero, and the magnetic flux is
The gap G can be regarded as a mere gap even if the magnetic sensor element 3 is present therein.

The number and arrangement of the plurality of gaps provided in the magnetic yoke 2 are arbitrary. For example, three gaps having a length of 5 mm (in the present embodiment, the gap G and the non-magnetic member 2).
N ₁ , 2N ₂ ), and if the magnetic sensor element 3 is inserted into one of them (the gap G in the present embodiment), the other 2
Gaps (in the present embodiment, the nonmagnetic portions 2N ₁ , 2N 2
The magnetic portion (the magnetic portion 2M _{2 in the} present embodiment) sandwiched between N ₂ ) can be the detachable portion 2D. In this case, the total length of the gap is larger than that of the current sensor device using the Hall element.
The measurement error due to the change in the length of the void portion due to the repetition of desorption of D becomes small.

When a flux gate magnetic sensor element is used as the magnetic sensor element 3 and the length of the gap of the magnetic yoke 2 is increased, the magnetic flux density in the magnetic yoke 2 is reduced. As the ferrite, a ferrite whose saturation magnetic flux density is not so large can be used. Ferrite has the advantage of low eddy current loss compared to metallic magnetic materials, and is a sintered body,
It is easy to smooth the end face by polishing or the like. Therefore, according to the present embodiment, it is possible to reduce the difference in height of the unevenness on the end face of the detachable portion 2D, and as a result, the change in the length of the void portion itself due to the repeated attachment and detachment of the detachable portion 2D is reduced. Can be smaller. Further, no magnetic saturation occurs due to the protrusions on the end faces of the magnetic body part facing each other.

As described above, according to the present embodiment, it is possible to increase the total length of the gap portion of the magnetic yoke 2 and to reduce the length of the gap portion due to the repeated attachment and detachment of the detachable portion 2D. Combined with the fact that the fluctuation can be reduced, the ratio of the fluctuation of the length of the air gap to the total length of the air gap of the magnetic yoke 2 can be made sufficiently small.
It is possible to reduce a measurement error due to a change in the length of the gap portion due to the repeated attachment and detachment of the detachable portion 2D.

This will be described with specific numerical values. For example, the height difference of the irregularities on the cut surface of ferrite is about 10 μm even when the cut surface is not polished,
By polishing, the thickness can be reduced to 1 μm or less. Therefore, the level difference of the unevenness on the end face of the detachable portion 2D can be made substantially the same. On the other hand, non-magnetic member part length of 2N _1, 2N ₂ is a gap portion of the magnetic yoke 2 may be, for respectively, for example 5 mm. Then, detachable part 2
The height difference between the irregularities on the end face of D is 1/5000 to 1/500 of the length of the gap (the nonmagnetic portions 2N ₁ and 2N ₂ ). Therefore, a measurement error due to a change in the length of the gap portion due to the repeated attachment and detachment of the detachable portion 2D hardly affects the characteristics of the current sensor device.

If a material having high hardness such as a ceramic material is used as the material of the nonmagnetic portions 2N ₁ and 2N ₂ ,
Non-magnetic part 2 accompanying repetition of attachment and detachment of detachable part 2D
Variations in the lengths of N ₁ and 2N ₂ can be almost ignored. Therefore, a change in the length of the magnetic path J due to the repeated attachment and detachment of the detachable portion 2D can be almost ignored.

As described above, according to the current sensor device according to the present embodiment, the detachable portion 2D, which is a part of the magnetic yoke 2, can be detached. The work of passing the current carrier 1 is facilitated, and the deterioration of the characteristics due to the detachment of the detachable portion 2D can be prevented.

In the present embodiment, the detachable portion 2
Since the current carrier 1 can be introduced into the hole of the magnetic yoke 2 through a portion opened by separating D from the main body portion, the size of the hole of the magnetic yoke 2 The required minimum size determined by the outer diameter of the portion arranged in the second hole can be obtained. Further, from this, according to the present embodiment, the difference between the shape of the hole of the magnetic yoke 2 and the outer shape of the current carrier 1 can be reduced, and as a result, the position of the current carrier 1 with respect to the magnetic yoke 2 Deterioration of characteristics due to fluctuation can be prevented.

According to the present embodiment, the size of the current sensor device can be reduced because it is not necessary to make the hole of the magnetic yoke 2 larger than necessary.

As described above, the current sensor device according to the present embodiment can be easily applied to an electric vehicle or the like, and has an extremely large industrial contribution.

[0073] In the present embodiment, the boundary portion of the magnetic yoke 2, a boundary portion between the magnetic body portion 2M ₂ and the non-magnetic portion 2N _1, a magnetic unit 2M ₂ and the non-magnetic portion 2N ₂ 2
Instead of a separable at a point, as separable at two points of the boundary portion between the magnetic body portion 2M ₁ and the boundary portion between the non-magnetic portion 2N _1, the magnetic body portion 2M ₃ and the non-magnetic portion 2N ₂ Is also good. In this case, the removable portion 2D comprises a magnetic body portion 2M ₂ and the non-magnetic portion 2N _1, 2N _2.

In the present embodiment, the magnetic portions 2M ₁ , 2M ₂ and 2M ₃ are replaced with the non-magnetic portions 2N ₁ and 2N _2.
A second magnetic body portion made of a second magnetic body having a lower magnetic permeability than the first magnetic body used in the first embodiment may be provided. Even in this case, if the difference between the magnetic permeability of the first magnetic body and the magnetic permeability of the second magnetic body is large, the same operation and effect as described above can be obtained. In this case, in this case, the magnetic parts 2M ₁ , 2M
M ₂ and 2M ₃ correspond to the first magnetic body in the present invention.

[Second Embodiment] FIG. 3 is a sectional view showing a main part of a current sensor device according to a second embodiment of the present invention. The magnetic yoke 2 according to the present embodiment
Removed the non-magnetic portion 2N ₂ in the embodiment of, and the upper end of the right lower portion and the magnetic portion 2M ₃ of the magnetic body portion 2M _2, it is butted separable. In the present embodiment,
The magnetic yoke 2 is made separable at two points at the boundary of the boundary portion between the magnetic body portion 2M ₂ and the non-magnetic portion 2N _1, the magnetic portion 2M ₂ and the magnetic unit 2M _3, the magnetic body portion 2M ₂ is a detachable portion 2D. Instead of a separable boundary portion between the magnetic body portion 2M ₂ and the non-magnetic portion 2N _1, it may be separated at the boundary portion between the magnetic body portion 2M ₁ and the non-magnetic portion 2N _1.

Other structures, operations and effects of the present embodiment are the same as those of the first embodiment.

[Third Embodiment] FIG. 4 is a sectional view showing a main part of a current sensor device according to a third embodiment of the present invention. The magnetic yoke 2 according to the present embodiment
The nonmagnetic portions 2N ₁ and 2N ₂ in the embodiment are arranged on the upper side of the entire magnetic yoke 2.

That is, in this embodiment, the magnetic member 2
M ₁ forms a part of the left side of the lower side part, a part of the left side part and a part of the left side of the upper side part of the whole magnetic yoke 2. Magnetic material portion 2M ₃ is configured to form a right portion of the right side portion and right side portion and upper portion of the lower side portion of the total of the magnetic yoke 2. Magnetic material portion 2M ₃ is adapted to form part of the central upper portion of the total of the magnetic yoke 2.

The non-magnetic portion 2N ₁ is disposed between the upper right end of the magnetic portion 2M ₁ and the left end of the magnetic portion 2M ₂ , and is located on the upper side of the entire magnetic yoke 2. To form a part. Non-magnetic portion 2N ₂ is disposed between the right end portion of the magnetic body portion 2M ₃ of the upper left portion and the magnetic portion 2M _2, a part of an upper side portion of the total of the magnetic yoke 2 Is formed.

[0080] In this embodiment, the magnetic yoke 2, 2 of the boundary portion between the magnetic body portion 2M ₂ and the boundary portion between the non-magnetic portion 2N _1, a magnetic unit 2M ₂ and the non-magnetic portion 2N ₂ It can be separated at some points. Accordingly, the magnetic portion 2M ₂ has a removable portion 2D. The length of the detachable portion 2D is equal to or larger than the outer diameter of the portion of the current carrier 1 that is arranged in the hole of the magnetic yoke 2.

In the present embodiment, the removable portion 2D (magnetic portion 2M ₂ ) and the non-magnetic portion 2
N ₁ and 2N ₂ are arranged on a straight line. Therefore, the position of the detachable portion 2D is in the direction along the magnetic path J (left-right direction).
, The sum of the lengths of the magnetic material portion and the non-magnetic material portion along the magnetic path J does not change. As described above, in the present embodiment, the detachable portion 2D changes the position of the detachable portion 2D in the direction along the magnetic path J, so that the
It can be said that M ₁ , 2M ₂ , 2M ₃ and the nonmagnetic portions 2N ₁ , 2N ₂ are arranged at positions where the sum of their respective lengths along the magnetic path does not change.

As described above, according to the present embodiment, even if the position of the detachable portion 2D fluctuates in the direction along the magnetic path J with the detachment of the detachable portion 2D, the magnetic member 2M ₁ ,
Since the sum of the lengths of the 2M ₂ , 2M ₃ and the nonmagnetic portions 2N ₁ , 2N ₂ along the magnetic path does not change, the characteristics of the current sensor device are not affected. Therefore, it is not necessary to form the nonmagnetic portions 2N ₁ and 2N ₂ with a hard material.

Incidentally, with the attachment and detachment of the detachable portion 2D,
Even if the position of the detachable portion 2D is slightly displaced in the direction perpendicular to the magnetic path J, the displacement is caused by the nonmagnetic member 2
Since only the facing area between the magnetic parts 2M ₁ and 2M ₂ and the magnetic parts 2M ₂ and 2M ₃ opposed to _{each other} with N ₁ and 2N ₂ therebetween is reduced, the magnetic parts 2M ₁ , 2M ₂ and 2M are reduced. _{If 3} is not magnetically saturated, it hardly affects the total magnetic resistance of the magnetic path J and hardly affects the characteristics of the current sensor device.

In this embodiment, the magnetic member 2
The boundary between M ₁ and the non-magnetic part 2N ₁ and the magnetic part 2M ₃
And _two non-magnetic portions 2N ₂ at the boundary. In this case, the length of the detachable portion 2D composed of the magnetic portion 2M ₂ and the non-magnetic portions 2N ₁ and 2N ₂ is equal to the outer diameter of the portion of the current carrier 1 that is arranged in the hole of the magnetic yoke 2. That is all.

Other structures, operations, and effects of the present embodiment are the same as those of the first embodiment.

[Fourth Embodiment] FIG. 5 is a sectional view showing a main part of a current sensor device according to a fourth embodiment of the present invention. In the present embodiment, the magnetic yoke includes three non-magnetic portions. In the present embodiment,
A magnetic yoke 12 is provided instead of the magnetic yoke 2 in the first embodiment. The magnetic yoke 12 has a gap G. The gap G is disposed at a position closer to the right than the center of the lower side portion of the entire magnetic yoke 12.

The magnetic yoke 12, when viewed clockwise starting from the left end of the gap G, has a magnetic portion 12M ₁ , a non-magnetic portion 12N ₁ , a magnetic portion 12M ₂ , a non-magnetic portion 12N ₂ , Body part 12M ₃ , non-magnetic part 12N ₃ , magnetic part 12M ₄
Are arranged along the magnetic path in this order. Non-magnetic part 12N
Reference numeral ₁ is disposed at a position on the left side of the center of the lower side portion of the entire magnetic yoke 12. Non-magnetic part 12N
₂ and 12N ₃ are the non-magnetic portions 2 in the third embodiment.
It is arranged at the same position as N ₁ and 2N ₂ .

[0088] In this embodiment, the magnetic yoke 12, a second boundary between the magnetic body portion 12M ₃ and the boundary portion between the non-magnetic portion 12N _2, the magnetic material portion 12M ₃ and non-magnetic member part 12N ₃ It can be separated at some points. Therefore, the magnetic part 1
2M ₃ has become a detachable portion 12D. The length of the detachable portion 12D is equal to or larger than the outer diameter of the portion of the current carrier 1 that is arranged in the hole of the magnetic yoke 2.

[0089] In the present embodiment, the boundary portion of the magnetic yoke 12, a boundary portion between the magnetic body portion 12M ₂ and the non-magnetic portion 12N _2, the magnetic body portion 12M ₄ and the non-magnetic material portion 12N ₃ May be separable at two locations. In this case, the magnetic portion 12M ₃ and the non-magnetic portions 12N ₂ , 12N
The length of the detachable portion 12D made of N ₃ is the length of the current carrier 1.
Of these, the outer diameter of the portion arranged in the hole of the magnetic yoke 2 should be larger than the outer diameter.

The other configurations, operations, and effects of the present embodiment are the same as those of the third embodiment.

[Fifth Embodiment] FIG. 6 is a sectional view showing a main part of a current sensor device according to a fifth embodiment of the present invention. In the present embodiment, the nonmagnetic portion of the magnetic yoke is made to be a detachable portion. In the present embodiment, a magnetic yoke 22 is provided instead of the magnetic yoke 2 in the first embodiment. The magnetic yoke 22 has a gap G. The gap G is disposed at a position closer to the right than the center of the lower side portion of the entire magnetic yoke 22.

The magnetic yoke 22, when viewed clockwise starting from the left end of the gap G, has a magnetic portion 22M ₁ , a non-magnetic portion 22N ₁ , a magnetic portion 22M ₂ , a non-magnetic portion 22N ₂ , It is arranged along the magnetic path in the order of the body portion 22M _3. Non-magnetic portion 22N ₁ is disposed to the left of the position of the center of the lower side portion of the total magnetic yoke 22. Non-magnetic portion 22N ₂ is disposed near the center of the upper side portion of the total magnetic yoke 22.

[0093] In this embodiment, the magnetic yoke 22, a second boundary between the magnetic body portion 22M ₂ and the boundary portion between the non-magnetic portion 22N _2, the magnetic material portion 22M ₃ and the non-magnetic portion 22N ₂ It can be separated at some points. Therefore, the non-magnetic portion 22N ₂ is a removable portion 22D. Thus, in this embodiment, the removable portion 22D comprises a non-magnetic portion 22N _2. The length of the removable portion 22D is equal to or larger than the outer diameter of the portion of the current carrier 1 that is arranged in the hole of the magnetic yoke 2.

In this embodiment, since the non-magnetic portion 22N ₂ is the removable portion 22D, the removable portion 2D
The change in the position of the detachable portion 22D accompanying the detachment of 2D is as follows.
It does not affect the characteristics of the current sensor device at all.

In the present embodiment, the non-magnetic member 22
Since N ₂ has a removable portion 22D, if separate means for fixing the position of the current carrier 1, removable part 2
Almost U without detachable part 22D without re-attaching 2D
It is also possible to use only the character-shaped body portion as the magnetic yoke.

The other configurations, operations, and effects of this embodiment are the same as those of the first embodiment.

[Sixth Embodiment] FIG. 7 is a sectional view showing a main part of a current sensor device according to a sixth embodiment of the present invention. The present embodiment is provided with a positioning member for positioning the current carrier with respect to the magnetic yoke.

In the present embodiment, a magnetic yoke 32 is provided instead of the magnetic yoke 2 in the first embodiment. The magnetic yoke 32 has a gap G. Gap G
Are disposed on the right side of the center of the lower side portion of the entire magnetic yoke 32.

The magnetic yoke 32 has a magnetic body portion 32M ₁ , a non-magnetic body portion 32N ₁ , a magnetic body portion 32M ₂ , a non-magnetic body portion 32N ₂ , when viewed clockwise starting from the left end of the gap G. Body part 32M ₃ , non-magnetic part 32N ₃ , magnetic part 32M ₄
Are arranged along the magnetic path in this order. These are the magnetic part 12M ₁ and the non-magnetic part 12 in the fourth embodiment.
N ₁ , the magnetic part 12M ₂ , the non-magnetic part 12N ₂ , the magnetic part 12M ₃ , the non-magnetic part 12N ₃ , and the magnetic part 12M ₄ are arranged at the same positions.

[0100] In this embodiment, the magnetic yoke 32, a second boundary between the magnetic body portion 32M ₃ and the boundary portion between the non-magnetic portion 32N _2, the magnetic material portion 32M ₃ and non-magnetic member part 32N ₃ It can be separated at some points. Therefore, the magnetic part 3
2M ₃ is a removable portion 32D. The length of the detachable portion 32D is equal to or greater than the outer diameter of the portion of the current carrier 1 that is arranged in the hole of the magnetic yoke 2.

In the present embodiment, a positioning member 35 for positioning the current carrier 1 with respect to the magnetic yoke 32 is provided in the hole of the magnetic yoke 32. The positioning member 35 corresponds to the positioning means in the present invention. The positioning member 35 has an outer shape that just fits in the hole of the magnetic yoke 32. The positioning member 35 has a hole having a rectangular cross section, for example, for holding the current carrier 1. The length of one side of this hole is substantially equal to the outer diameter of the current carrier 1. The positioning member 35 has the same length as the removable portion 32D of the magnetic yoke 32, and is divided into a removable portion 35B adjacent to the removable portion 32D and the remaining main body portion 35A. The detachable portion 35B is joined to the detachable portion 32D, and is detached together with the detachable portion 32D. The positioning member 35 can be formed of a ceramic material, a plastic material, a rubber material, or the like.

FIG. 8 is a sectional view showing a state in which the removable portions 32D and 35B are separated. As shown in this figure, in the present embodiment, the current carrier 1 is
The 2D, 35B is inserted into the hole of the main body portion 35A of the positioning member 35 with the 2D and 35B separated from the main body portion. Thereafter, when the detachable portions 32D and 35B are attached to the main body, the magnetic yoke 32 is completed and the positioning member 3 is attached.
5, the current carrier 1 is positioned and fixed with respect to the magnetic yoke 32.

According to the present embodiment, the positioning member 35
Is provided, the position fluctuation of the current carrier 1 with respect to the magnetic yoke 32 can be almost completely suppressed, and the characteristic deterioration of the current sensor device due to the position fluctuation of the current carrier 1 can be prevented.

[0104] In the present embodiment, the boundary portion of the magnetic yoke 32, a boundary portion between the magnetic body portion 32M ₂ and the non-magnetic portion 32N _2, the magnetic body portion 32M ₄ and the non-magnetic material portion 32N ₃ May be separable at two locations. In this case, the magnetic portion 32M ₃ and the non-magnetic portions 32N ₂ , 32N
The length of the detachable portion 32D made of N ₃ is the length of the current carrier 1.
Of these, the outer diameter of the portion arranged in the hole of the magnetic yoke 2 should be larger than the outer diameter. In this case, the length of the removable portion 35B of the positioning member 35 may be equal to the length of the removable portion 32D.

Other structures, operations and effects of the present embodiment are the same as those of the fourth embodiment.

The present invention is not limited to the above embodiments, but can be variously modified. For example, it is preferable to use ferrite as the magnetic body of the magnetic yoke,
If the length of the non-magnetic material portion is sufficiently large, the length of the void portion relative to the total length of the void portion including the non-magnetic material portion in the magnetic yoke even if the height difference of the unevenness of the end face of the magnetic material portion is about 100 μm. Since the variation ratio can be made sufficiently small, a magnetic member having a structure in which a thin plate made of a metallic magnetic material coated with an insulating material can be used may be used.

As the magnetic sensor element, an element other than the flux gate element can be used.
For example, if a magnetic material portion of a magnetic yoke, such as an amorphous magnetic thin material, having a high saturation magnetic flux density, a small electrical conductivity, and not requiring interlayer insulation for suppressing eddy current is used, Can be polished. Therefore, in this case, the ratio of the variation in the length of the gap to the total length of the gap including the nonmagnetic portion in the magnetic yoke can be made sufficiently small, and a Hall element can be used as the magnetic sensor element. is there.

Further, a portion of the magnetic yoke including the magnetic sensor element may be a detachable portion. However, it is preferable that a portion that does not include the magnetic sensor element be a detachable portion from the viewpoint that wiring is connected to the magnetic sensor element.

[0109]

As described above, claims 1 to 1
0, the magnetic yoke includes the magnetic material portion and the non-magnetic material portion, and is separable at the boundary between the magnetic material portion and the non-magnetic material portion. Can be detachably attached, and the characteristic can be prevented from deteriorating due to the attachment / detachment.

Further, according to the current sensor device of the sixth aspect, the detachable portion can be moved along the magnetic path by changing the position in the direction along the magnetic path. Since it is arranged at a position where the total length does not change, the total length of each of the magnetic material portion and the non-magnetic material portion along the magnetic path does not change with the attachment and detachment of the detachable portion, There is an effect that deterioration of characteristics due to desorption can be further prevented.

Further, according to the current sensor device of the present invention, since the positioning means for positioning the current carrier with respect to the magnetic yoke is further provided, the characteristic deterioration due to the fluctuation of the position of the current carrier with respect to the magnetic yoke is provided. The effect that it can prevent is produced.

Further, according to the current sensor device of the present invention, since the magnetic sensor element is a flux gate magnetic sensor element, the total length of each of the gap and the non-magnetic material along the magnetic path can be reduced. It is possible to increase the size, and it is possible to prevent the deterioration of the characteristics due to the desorption.

According to the current sensor device of the ninth aspect, the magnetic body portion is made of ferrite.
The end face of the magnetic part at the boundary between the magnetic part and the non-magnetic part can be made smoother, and the effect of deteriorating characteristics due to attachment and detachment can be further prevented.

According to the eleventh or twelfth aspect of the present invention, the magnetic yoke includes the first magnetic body portion made of the first magnetic body and the first magnetic body portion having the smaller magnetic permeability than the first magnetic body. A second magnetic material portion made of a second magnetic material,
The magnetic yoke can be separated at the boundary between the magnetic part and the second magnetic part, so that a part of the magnetic yoke can be attached and detached, and deterioration of characteristics due to attachment and detachment can be prevented. It works.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a current sensor device according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a circuit configuration of the current sensor device according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a main part of a current sensor device according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a main part of a current sensor device according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a main part of a current sensor device according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a main part of a current sensor device according to a fifth embodiment of the present invention.

FIG. 7 is a sectional view showing a main part of a current sensor device according to a sixth embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a state where a removable portion is separated in a current sensor device according to a sixth embodiment of the present invention.

FIG. 9 is an explanatory diagram for explaining the operation principle of the flux gate element.

FIG. 10 is a cross-sectional view illustrating a main part of an example of a current sensor device using a Hall element.

FIG. 11 is a sectional view showing a main part of an example of a current sensor device in which a part of a magnetic yoke is detachable.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 current carrier 2 magnetic yoke 3 magnetic sensor element
2M ₁ , 2M ₂ , 2M ₃ ... magnetic part, 2N ₁ , 2N ₂ ... non-magnetic part, 2D: detachable part, G: void, J: magnetic path.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission Date] August 15, 2000 (2008.1.
5)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Wherein said removable portion, a current sensor apparatus according to claim 1, characterized in that it comprises the magnetic body.

Wherein said removable portion, a current sensor apparatus according to claim 1, comprising the non-magnetic portion.

Wherein said removable portion, a current sensor apparatus according to claim 1, comprising the magnetic body and the non-magnetic portion.

Wherein said removable portion, by variations in the position of the removable portion in the direction along the magnetic path, the sum of the magnetic unit and the of each along the magnetic path of the non-magnetic portion length The current sensor device according to claim 1 , wherein the current sensor is arranged at a position where the current does not change.

6. Further, the current sensor apparatus according to claim 1, further comprising a positioning means for positioning the current carrier with respect to the magnetic yoke.

Wherein said magnetic sensor element claims 1 to characterized in that it is a flux-gate magnetic sensor element 6
The current sensor device according to any one of the above.

8. A current sensor apparatus according to any one of claims 1 to 7, characterized in said magnetic body be made of ferrite.

9. to the claims 1, characterized in that the length along the magnetic path of the non-magnetic portion is 0.1mm or more
9. The current sensor device according to any one of 8 .

10. An annular ring which is arranged so as to surround a current carrier through which a current to be measured flows, has a gap in a part thereof, and forms a magnetic path for passing a magnetic flux generated by the current to be measured flowing through said current carrier. A magnetic yoke, a magnetic sensor element disposed in the gap of the magnetic yoke and detecting a magnetic field in the gap generated by a measured current flowing through the current carrier, wherein the magnetic yoke is arranged along a magnetic path. It arranged Te, a first magnetic portion made of a first magnetic body, the first of the second magnetic body and a free Mutotomoni than magnetic consist smaller second magnetic permeability The first magnetic body portion and the second magnetic member
At least one separable boundary between the body and the body
Includes a field portion, the body portion further the magnetic yoke, which constitutes the main part
And at least one end is in front of the first magnetic body.
The separable boundary provided between the second magnetic part and the second magnetic part.
A detachable portion which is disposed on the boundary portion and is detachable from the main body portion.
A current sensor device having a wearable portion .

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0037

[Correction method] Change

[Correction contents]

[0037]

A first current sensor device according to the present invention is arranged so as to surround a current carrier through which a current to be measured flows, has a gap in a part thereof, and measures a current to flow through the current carrier. An annular magnetic yoke that forms a magnetic path through which a magnetic flux generated by the magnetic yoke passes, and a magnetic sensor element that is arranged in the gap of the magnetic yoke and detects a magnetic field in the gap generated by the measured current flowing through the current carrier. provided, the magnetic yoke, are arranged along a magnetic path, and a non-magnetic portion made of a magnetic material portion and a non-magnetic material made of a magnetic material
In addition, a small part provided between the magnetic part and the non-magnetic part
It includes at least one separable boundary,
The main body, which constitutes the main part, and at least one
One end is provided between the magnetic part and the non-magnetic part.
Located at a separable boundary part, detachable from the main body part
And a removable portion .

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction contents]

In the first current sensor device of the present invention, the magnetic sensor
The yoke is located at the boundary between the magnetic and non-magnetic parts.
And detachable part of the magnetic yoke
It is.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction contents]

In the first current sensor device of the present invention ,
The detachable portion may include a magnetic part, a non-magnetic part, or a magnetic part and a non-magnetic part.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

Further, in the first current sensor apparatus of the present invention, removable portion detachable portion in the direction along the path
The magnetic member and the non-magnetic member may be arranged at positions where the sum of their respective lengths along the magnetic path does not change due to a change in the minute position.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

The second current sensor device of the present invention is arranged so as to surround the current carrier through which the current to be measured flows, has a gap in a part thereof, and passes the magnetic flux generated by the current to be measured flowing through the current carrier. An annular magnetic yoke forming a magnetic path to be formed, and a magnetic sensor element disposed in the gap of the magnetic yoke and detecting a magnetic field in the gap generated by the measured current flowing through the current carrier. A first magnetic body portion made of a first magnetic body and a second magnetic body portion made of a second magnetic body having a lower magnetic permeability than the first magnetic body, arranged along the path; In addition, the first magnetic
At least one provided between the body and the second magnetic body;
The magnetic yoke further comprises
A main body part constituting a main part and at least one end
Is provided between the first magnetic body and the second magnetic body.
Is located at the detachable boundary where
And a detachable portion that can be attached .

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

[0046] In the second current sensor apparatus of the present invention, a magnetic
The yoke is a boundary between the first magnetic part and the second magnetic part.
Part is separable and part of the magnetic yoke
Is removable.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Deleted

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

[0109]

As described above, claims 1 to 9 are described.
Of According to the current sensor apparatus according to any magnetic yoke and a magnetic material portion and a non-magnetic material portion are separable at the boundary portion between the magnetic body and the non-magnetic portion, a magnetic yoke Can be detachably attached, and the characteristic can be prevented from deteriorating due to the attachment / detachment.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0110

[Correction method] Change

[Correction contents]

Further, according to the current sensor apparatus according to claim 5, removable portion detachable portion in the direction along the path
Since the total length of the magnetic material portion and the non-magnetic material portion along the magnetic path does not change due to the change of the minute position, the magnetic material portion and the non-magnetic material portion The sum of the lengths of the nonmagnetic portions along the magnetic path does not change, so that the effect of deteriorating characteristics due to desorption can be further prevented.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0111

[Correction method] Change

[Correction contents]

Further, according to the current sensor device of the sixth aspect, since the positioning means for positioning the current carrier with respect to the magnetic yoke is further provided, the characteristic due to the fluctuation of the position of the current carrier with respect to the magnetic yoke is provided . This has the effect that deterioration can be prevented.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0112

[Correction method] Change

[Correction contents]

[0112] Further, according to the current sensor apparatus according to claim 7, since the magnetic sensor element and a flux gate magnetic sensor element, respectively along the magnetic path of the air gap and non-magnetic member part the total length It is possible to increase the size, and it is possible to prevent the deterioration of the characteristics due to the desorption.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

Further, according to the current sensor device of the eighth aspect , since the magnetic part is made of ferrite,
The end face of the magnetic part at the boundary between the magnetic part and the non-magnetic part can be made smoother, and the effect of deteriorating characteristics due to attachment and detachment can be further prevented.

[Procedure amendment 14]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

Further, according to the current sensor device of the tenth aspect , the magnetic yoke includes the first magnetic member made of the first magnetic material and the second magnetic member having a smaller magnetic permeability than the first magnetic material. and a second magnetic portion made of magnetic material, can be separated at the boundary between the first magnetic body and second magnetic body portions
In addition, there is an effect that a part of the magnetic yoke can be attached and detached, and deterioration of characteristics due to attachment and detachment can be prevented.

Claims (12)

[Claims] 1. An annular shape which is arranged so as to surround a current carrier through which a current to be measured flows, has a gap in a part thereof, and forms a magnetic path for passing a magnetic flux generated by the current to be measured flowing through said current carrier. A magnetic yoke, a magnetic sensor element disposed in the gap of the magnetic yoke and detecting a magnetic field in the gap generated by a measured current flowing through the current carrier, wherein the magnetic yoke is arranged along a magnetic path. A magnetic body portion made of a magnetic material and a non-magnetic material portion made of a non-magnetic material, which are separable at at least one boundary portion between the magnetic material portion and the non-magnetic material portion. A current sensor device characterized by the above-mentioned. 2. The magnetic yoke according to claim 1, wherein the magnetic yoke comprises a main body part constituting a main part, and a detachable part having at least one end disposed at the separable boundary part and detachable from the main body part. The current sensor device according to claim 1, further comprising: 3. The current sensor device according to claim 2, wherein the removable portion includes the magnetic body. 4. The current sensor device according to claim 2, wherein the removable portion includes the non-magnetic member. 5. The current sensor device according to claim 2, wherein the detachable portion includes the magnetic part and the non-magnetic part. 6. The removable portion is located at a position where the total length of the magnetic body portion and the non-magnetic body portion along the magnetic path does not change due to a change in the position along the magnetic path. The current sensor device according to claim 2, wherein the current sensor device is arranged. 7. The current sensor device according to claim 1, further comprising a positioning unit for positioning the current carrier with respect to the magnetic yoke. 8. The magnetic sensor element according to claim 1, wherein the magnetic sensor element is a flux gate magnetic sensor element.
The current sensor device according to any one of the above. 9. The current sensor device according to claim 1, wherein the magnetic member is made of ferrite. 10. The current sensor device according to claim 1, wherein a length of the nonmagnetic portion along a magnetic path is 0.1 mm or more. 11. An annular member which is arranged so as to surround a current carrier through which a current to be measured flows, has a gap in a part thereof, and forms a magnetic path for passing a magnetic flux generated by the current to be measured flowing through said current carrier. A magnetic yoke, a magnetic sensor element disposed in the gap of the magnetic yoke and detecting a magnetic field in the gap generated by a measured current flowing through the current carrier, wherein the magnetic yoke is arranged along a magnetic path. A first magnetic body portion made of a first magnetic body, and a second magnetic body portion made of a second magnetic body having a smaller magnetic permeability than the first magnetic body, A current sensor device which is separable at at least one boundary portion between a first magnetic body and the second magnetic body. 12. The magnetic yoke has a main body part constituting a main part, and a detachable part which is disposed at at least one end at the separable boundary part and is detachable from the main body part. The current sensor device according to claim 11, wherein: