WO2017217267A1 - Electric current sensor - Google Patents

Abstract

An electric current sensor is provided with: a magnetism detection element (11-14) for sensing magnetic flux emitted by an electric current path (210-240) and performing magnetoelectric conversion; and at least two magnetic shields (21, 21A-21N, 22, 22A-22N, 23, 24) disposed around the magnetism detection element, the magnetic shields shielding the magnetism detection element against magnetic flux from the exterior. The at least two magnetic shields include a first magnetic shield and a second magnetic shield that are disposed opposite each other while sandwiching the magnetism detection element and the electric current path. At least one among the first magnetic shield and the second magnetic shield has at least two base sections and a connection section by which the at least two base parts are linked. A recessed section (1, 1A, 4) that is recessed further than a peripheral section is formed in a surface that faces the other among the first magnetic shield and the second magnetic shield.

Description

Current sensor Cross-reference of related applications

This application includes Japanese application No. 2016-119135 filed on June 15, 2016, Japanese application No. 2016-2226096 filed on November 21, 2016, and application filed on December 12, 2016. Which is based on Japanese Patent Application No. 2016-240590, which is incorporated herein by reference.

The present disclosure relates to a current sensor that detects a magnetic flux generated from a current path and performs magnetoelectric conversion, and a current sensor that detects a magnetic field generated from the current path and converts it into an electric signal, and detects a current flowing through the current path. Is.

Conventionally, there is a current detection system disclosed in Patent Document 1 as a current sensor. The current detection system includes a magnetic plate, a bus bar corresponding to these, and a semiconductor substrate. In addition, a magnetoelectric conversion element that converts magnetic flux into an electric signal is formed on the semiconductor substrate.

JP2015-194472A

According to an example of the current detection system disclosed in Patent Document 1, the current detection system is arranged such that two sets of magnetic plates are adjacent to each other. A bus bar and a semiconductor substrate are disposed between the opposing magnetic plates in each set. Therefore, in the current detection system, the magnetic plate disposed opposite to the one bus bar and the semiconductor substrate and the magnetic plate disposed opposite to the other bus bar and the semiconductor substrate are separated. For this reason, there is a possibility that the current detection system generates a leakage magnetic field from the end of the magnetic plate.

Also, when the magnetic plate of the current detection system is magnetically saturated, it is magnetically saturated from the surface on the side facing the semiconductor substrate. For this reason, in the current detection system, a leakage magnetic field from the magnetic plate due to magnetic saturation may easily affect the magnetoelectric conversion element.

According to another example of the current detection system disclosed in Patent Document 1, the current detection system is arranged so that three sets of magnetic plates (hereinafter referred to as magnetic shields) are adjacent to each other. A bus bar and a semiconductor substrate are arranged between the magnetic shields arranged to face each other. Therefore, in the current detection system, adjacent magnetic shields are separated.

In the following, a pair of magnetic shields, a bus bar sandwiched between the pair of magnetic shields, and a semiconductor substrate are also referred to as phases. Therefore, it can be said that the current detection system has three phases arranged next to each other. One of the opposed magnetic shields is also called an upper shield and the other is also called a lower shield.

In the current detection system configured as described above, when a relatively large current such as 1200 A is supplied to a bus bar of a certain phase, a magnetic field is generated from the bus bar. The magnetic field concentrates inside the magnetic shield disposed opposite to the bus bar and propagates to the adjacent magnetic shield. In the magnetic shield arranged at the end, magnetic field exchange occurs between the upper shield and the lower shield. For this reason, in the current detection system, there is a possibility that a part of the magnetic field exchange is sensed by the magnetoelectric conversion element at the end, resulting in a current detection error.

The present disclosure has as its first object to provide a current sensor that can suppress the leakage magnetic field and can suppress the influence of the leakage magnetic field due to magnetic saturation, and secondly to provide a current sensor that can detect a current with high accuracy. The purpose.

According to the first aspect of the present disclosure, the current sensor detects a magnetic flux generated from the current path and performs a magnetoelectric conversion, and is disposed around the magnetic detection element, and is external to the magnetic detection element. And at least two magnetic shields for shielding magnetic flux.

The at least two magnetic shields have a first magnetic shield and a second magnetic shield arranged to face each other while sandwiching the magnetic detection element and the current path. At least one of the first magnetic shield and the second magnetic shield has at least two base portions and a connecting portion connecting at least two base portions, and the other first magnetic shield and second magnetic shield. A recess that is recessed from the periphery is formed on the opposite surface.

Thus, since the current sensor is formed by connecting the two base portions of the magnetic shield by the connecting portion, the leakage magnetic field from the end portion of the base portion can be suppressed. That is, the current sensor can suppress the leakage magnetic field from the end portion of the base portion, compared to the case where the two base portions are not connected by the connecting portion and are divided.

In addition, since the current sensor has a recess formed in the magnetic shield, the magnetic flux generated from the current path can flow on the surface of the magnetic shield opposite to the facing region side. For this reason, in the current sensor, the side opposite to the facing region side in the magnetic shield, that is, the side far from the magnetic detection element in the magnetic shield is likely to be magnetically saturated. Therefore, the current sensor can suppress the leakage magnetic field due to the magnetic saturation of the magnetic shield from affecting the magnetic detection element.

According to the second aspect of the present disclosure, the current sensor is a current sensor that individually detects a current flowing through each of the plurality of current paths, and is disposed to face one current path and is generated from the current path. A magnetic detection element that detects and converts the magnetic detection element into an electric signal, and shields a magnetic field from the outside with respect to the magnetic detection element, and a pair of first shields disposed opposite to each other while sandwiching the current path and the magnetic detection element A plurality of phases having a magnetic shield part including a second shield corresponding to each of a plurality of current paths. In each phase, the first shield, the current path, the magnetic detection element, and the second shield are laminated in this order in the lamination direction, and are arranged in the arrangement direction orthogonal to the lamination direction.

Here, among the plurality of phases, an end phase in the arrangement direction is an end phase, a first shield in the end phase is a first end phase shield, a second shield in the end phase is a second end phase shield, The magnetic detection element in FIG.

At least one of the first end-phase shield and the second end-phase shield has a leakage magnetic field from one end direction of one of the first end-phase shield and the second end-phase shield that is higher than that of the end-phase detection element. A magnetic field exchange unit is provided for exchanging the magnetic field between the first end-phase shield and the second end-phase shield so that the other of the one-end phase shield and the second end-phase shield can be easily reached.

Thus, according to the second aspect of the present disclosure, at least one of the first end-phase shield and the second end-phase shield includes the magnetic field exchange unit. Accordingly, the present disclosure provides that the leakage magnetic field from the extreme end portion in the arrangement direction of the first end-phase shield and the second end-phase shield is opposite to the end-phase detection element, and the other end-side first end-phase shield is disposed. And it becomes easy to reach the second terminal phase shield. For this reason, the present disclosure can suppress the leakage magnetic field from reaching the end phase detection element and can detect the current with high accuracy.

According to the third aspect of the present disclosure, the current sensor is a current sensor that individually detects a current flowing through each of the plurality of current paths, and is arranged to face one current path and generate a magnetic field generated from the current path. A magnetic detection element that detects and converts the magnetic detection element into an electric signal, and shields a magnetic field from the outside with respect to the magnetic detection element, and a pair of first shields disposed opposite to each other while sandwiching the current path and the magnetic detection element A plurality of phases having a magnetic shield part including a second shield corresponding to each of a plurality of current paths. In each phase, the first shield, the current path, the magnetic detection element, and the second shield are laminated in this order in the lamination direction, and are arranged in the arrangement direction orthogonal to the lamination direction.

Here, among the plurality of phases, an end phase in the arrangement direction is an end phase, a first shield in the end phase is a first end phase shield, a second shield in the end phase is a second end phase shield, The magnetic detection element in FIG.

The magnetic shield portion is continuously provided at the end portion in the arrangement direction of the first end-phase shield and the second end-phase shield in order to exchange the magnetic field between the first end-phase shield and the second end-phase shield, A magnetic field exchanging unit is provided in which the one end phase shield and the second end phase shield are integrated.

Thus, according to the third aspect of the present disclosure, the first end-phase shield and the second end-phase shield are continuously provided at the end portions in the arrangement direction of the first end-phase shield and the second end-phase shield. Is provided as a single unit. Thus, the present disclosure can reduce the occurrence of a leakage magnetic field from the end portions in the arrangement direction of the first end-phase shield and the second end-phase shield. For this reason, the present disclosure can suppress the leakage magnetic field from reaching the end phase detection element and can detect the current with high accuracy.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. In the drawing
It is a top view which shows schematic structure of the current sensor in 1st Embodiment, It is sectional drawing which follows the II-II line of FIG. It is sectional drawing which shows schematic structure of the current sensor in the modification 1 of 1st Embodiment, It is sectional drawing which shows schematic structure of the current sensor in the modification 2, It is sectional drawing which shows schematic structure of the current sensor in the modification 3, It is sectional drawing which shows schematic structure of the current sensor in the modification 4, It is sectional drawing which shows schematic structure of the current sensor in the modification 5, It is sectional drawing which shows schematic structure of the current sensor in the modification 6, It is sectional drawing which shows schematic structure of the current sensor in the modification 7, It is sectional drawing which shows schematic structure of the current sensor in the modification 8, It is sectional drawing which shows schematic structure of the sensor block in the modification 8, It is sectional drawing which shows schematic structure of the current sensor in the modification 9, It is sectional drawing which shows schematic structure of the current sensor in the modification 10, It is sectional drawing which shows schematic structure of the current sensor in the modification 11, It is sectional drawing which shows schematic structure of the current sensor in the modification 12, It is sectional drawing which follows the XVI-XVI line of FIG. It is sectional drawing which shows schematic structure of the current sensor in the modification 13, It is sectional drawing which shows schematic structure of the current sensor in the modification 14, It is sectional drawing which shows schematic structure of the current sensor in the modification 15, It is sectional drawing which shows schematic structure of the current sensor in the modification 16, It is sectional drawing which shows schematic structure of the current sensor in the modification 17, It is sectional drawing which shows schematic structure of the current sensor in the modification 18, It is a top view which shows schematic structure of the current sensor in the modification 19, It is sectional drawing which follows the XXIV-XXIV line in FIG. It is sectional drawing which follows the XXV-XXV line in FIG. It is sectional drawing of the 1st magnetic shield in a comparison object, It is sectional drawing which shows schematic structure of the 1st magnetic shield in the modification 20, It is sectional drawing which shows schematic structure of the 1st magnetic shield in the modification 21, It is sectional drawing which shows schematic structure of the 1st magnetic shield in the modification 22, It is sectional drawing which shows schematic structure of the 1st magnetic shield in the modification 23, It is sectional drawing which shows schematic structure of the 1st magnetic shield in the modification 24, It is a top view which shows schematic structure of the current sensor in the modification 25, It is sectional drawing which follows the XXXIII-XXXIII line in FIG. It is a top view from XXXIV direction in FIG. It is a top view which shows schematic structure of the current sensor in the modification 26, It is a top view which shows schematic structure of the current sensor in 2nd Embodiment, It is sectional drawing which follows the XXXVII-XXXVII line of FIG. It is sectional drawing which shows schematic structure of the current sensor in 3rd Embodiment, It is sectional drawing which shows schematic structure of the current sensor in the modification 1 of 3rd Embodiment, It is sectional drawing which shows schematic structure of the current sensor in the modification 2, It is sectional drawing which shows schematic structure of the current sensor in 4th Embodiment, It is sectional drawing which follows the XLII-XLII line | wire of FIG. It is sectional drawing which shows schematic structure of the current sensor in 5th Embodiment.

Hereinafter, a plurality of embodiments of the present disclosure will be described with reference to the drawings. In each embodiment, portions corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals and redundant description may be omitted. In each embodiment, when only a part of the configuration is described, the other configurations described above can be applied to other portions of the configuration.

In the following, the three directions orthogonal to each other are referred to as an X direction, a Y direction, and a Z direction. A plane defined by the X direction and the Y direction is an XY plane, a plane defined by the X direction and the Z direction is an XZ plane, and a plane defined by the Y direction and the Z direction is a YZ plane.

(First embodiment)
The current sensor 100 according to the first embodiment will be described with reference to FIGS. 1 and 2. The current sensor 100 is used for inverter control of a vehicle-mounted motor, for example. The current sensor 100 detects a current to be detected flowing in the bus bars 210 and 220 connected to the in-vehicle battery that supplies power to the in-vehicle motor for inverter control. Bus bars 210 and 220 correspond to current paths.

The current sensor 100 is used in, for example, an electric vehicle or a hybrid vehicle. Moreover, the current sensor 100 can employ, for example, a coreless current sensor that does not require a magnetic core.

The current sensor 100 includes a first magnetic detection element 11, a second magnetic detection element 12, a first magnetic shield 21, and a second magnetic shield 22.

Each of the first magnetic detection element 11 and the second magnetic detection element 12 includes, for example, a sensor chip, a bias magnet, and a circuit chip mounted on a substrate, and these are sealed with a sealing resin body and connected to the circuit chip. A configuration in which the lead is exposed to the outside of the sealing resin body can be employed. As the sensor chip, for example, a giant magnetoresistive element (GMR), an anisotropic magnetoresistive element (AMR), a tunnel magnetoresistive element (TMR), or a Hall element can be adopted.

1 and 2, the first magnetic detection element 11 and the second magnetic detection element 12 are arranged side by side in the X direction. As shown in FIG. 2, the first magnetic detection element 11 is disposed to face the first bus bar 210 in the Z direction. On the other hand, the second magnetic detection element 12 is disposed to face the second bus bar 220 in the Z direction. The Z direction can also be referred to as the thickness direction of the magnetic shields 21 and 22.

Each of the first magnetic shield 21 and the second magnetic shield 22 is made of a magnetic material and prevents the external magnetic field from passing through the magnetic detection elements 11 and 12. The first magnetic shield 21 and the second magnetic shield 22 are provided in common to the magnetic detection elements 11 and 12.

1 and 2, the first magnetic shield 21 and the second magnetic shield 22 are plate-like members. The first magnetic shield 21 and the second magnetic shield 22 are opposed to each other with a gap in the Z direction. The first magnetic shield 21 and the second magnetic shield 22 are arranged so as to sandwich the magnetic detection elements 11 and 12 and the bus bars 210 and 220 in the Z direction. Therefore, it can be said that the magnetic detection elements 11 and 12 are arranged in a region where the first magnetic shield 21 and the second magnetic shield 22 face each other.

As shown in FIGS. 1 and 2, the first magnetic shield 21 and the second magnetic shield 22 have different shapes. The second magnetic shield 22 is a plate-shaped plate member. The second magnetic shield 22 has a surface facing the first magnetic shield 21 and a surface opposite to the facing surface. The opposing surface and the opposite surface of the second magnetic shield 22 are flat surfaces. Further, the thickness of the second magnetic shield 22 in the Z direction is uniform over the entire area. It can be said that the opposite surface of the second magnetic shield 22 is the outer surface of the second magnetic shield 22.

In the present embodiment, the second magnetic shield 22 having a rectangular outer shape on the opposite surface and an outer surface on the opposite surface is employed. However, the present disclosure is not limited to this.

On the other hand, the first magnetic shield 21 is a plate-like member having a recess 1 as shown in FIG. That is, the first magnetic shield 21 has the recess 1 that is recessed from the periphery. As shown in FIG. 1, the recess 1 is provided from one end of the first magnetic shield 21 in the Y direction to the other end, and can be said to be a groove. In addition, it can be said that the recess 1 is formed from one end of the first magnetic shield 21 to the other end along the direction of current flow in the bus bars 210 and 220. The recess 1 is a hole with a bottom, and is not a hole that penetrates the first magnetic shield 21 in the Z direction.

The recess 1 is provided so as to be orthogonal to the magnetic flux flowing in the magnetic shields 21 and 22 when the detected current flows in the bus bars 210 and 220. The flow of magnetic flux in a magnetic shield such as the first magnetic shield 21 can be referred to as a magnetic flow path.

The first magnetic shield 21 has a surface facing the second magnetic shield 22 and a surface opposite to the facing surface. The opposite surface of the first magnetic shield 21 is a flat surface. However, the opposing surface of the first magnetic shield 21 is a flat surface in which a part that is recessed in part is formed. That is, the recessed portion corresponds to the recess 1. Therefore, the first magnetic shield 21 is formed with the concave portion 1 opened on the side facing the second magnetic shield 22. It can be said that the opposite surface of the first magnetic shield 21 is the outer surface of the first magnetic shield 21.

Further, it can be said that the first magnetic shield 21 has the thick part 2 and the thin part 3. The thick part 2 corresponds to a base part. On the other hand, the thin portion 3 corresponds to a connecting portion.

The thick part 2 is a part where the thickness in the Z direction is thicker than the thin part 3. The thin part 3 is sandwiched between two thick parts 2 and is provided continuously with the two thick parts 2. That is, the first magnetic shield 21 includes the thick part 2 facing the first magnetic detection element 11 and the thick part 2 facing the second magnetic detection element 12, and the two thick parts 2 are It is connected by the thin part 3.

Further, the opposite surface of the first magnetic shield 21 is configured to be flush with the thick portion 2 and the thin portion 3. On the other hand, the opposing surface of the first magnetic shield 21 differs in the position in the Z direction between the thick portion 2 and the thin portion 3. Therefore, it can be said that the concave portion 1 is a region opposed to the thin portion 3 and is sandwiched between the two thick portions 2. Further, it can be said that the first magnetic shield 21 is formed with a concave portion 1 which is recessed from the peripheral thick portion 2 and opened in the facing region at a position facing the thin portion 3.

Further, as shown in FIG. 1, the first magnetic shield 21 is provided with a recess 1 at a portion facing the middle between the first magnetic detection element 11 and the second magnetic detection element 12 when viewed from the Z direction. And preferred. That is, the recess 1 is provided at a portion facing the intermediate position between the two magnetic detection elements 11 and 12. The distance X1 from the first magnetic detection element 11 to the recess 1 is approximately the same as the distance X2 from the second magnetic detection element 12 to the recess 1. The current sensor 100 can suppress the influence of the leakage magnetic field on the magnetic detection elements 11 and 12 even when the leakage magnetic field is generated from the recess 1. However, the position of the recess 1 is not limited to this.

In the present embodiment, the first magnetic shield 21 having a rectangular outer shape on the opposite surface and an outer surface on the opposite surface is employed. However, the present disclosure is not limited to this.

The current sensor 100 is configured by assembling magnetic detection elements 11 and 12 and magnetic shields 21 and 22. Here, an assembly structure of each component of the current sensor 100 and the first bus bar 210 and the second bus bar 220 will be described. In the present embodiment, the first bus bar 210 and the second bus bar 220 having a flat plate shape are employed. In FIG. 1, the part extended in the Y direction in the 1st bus bar 210 and the 2nd bus bar 220 is shown in figure. Moreover, the 1st bus bar 210 and the 2nd bus bar 220 have the site | part arrange | positioned in parallel at intervals in the X direction. The detected current flows in the Y direction of the first bus bar 210 and the second bus bar 220 shown in FIG.

The current sensor 100 is assembled with the first bus bar 210 and the second bus bar 220 in order to detect the detected current flowing through the first bus bar 210 and the second bus bar 220. As shown in FIG. 2, the first magnetic shield 21 and the second magnetic shield 22 are disposed to face each other in the Z direction. In the region where the first magnetic shield 21 and the second magnetic shield 22 are opposed, the magnetic detection elements 11 and 12 and the bus bars 210 and 220 are disposed.

As shown in FIG. 2, the first magnetic detection element 11 is disposed between the first bus bar 210 and the first magnetic shield 21 in the Z direction. Specifically, the first magnetic detection element 11 is disposed between the first bus bar 210 and one thick portion 2 of the first magnetic shield 21. In addition, the first magnetic detection element 11 is disposed with a space between the first bus bar 210 and the first magnetic shield 21.

As shown in FIG. 2, the second magnetic detection element 12 is disposed between the second bus bar 220 and the first magnetic shield 21 in the Z direction. More specifically, the second magnetic detection element 12 is disposed between the second bus bar 220 and the other thick part 2 of the first magnetic shield 21. In addition, the second magnetic detection element 12 is disposed with a space between the second bus bar 220 and the first magnetic shield 21. In addition, the 2nd magnetic shield 22, the 1st bus bar 210, and the 2nd bus bar 220 are arrange | positioned at intervals in the Z direction.

The first bus bar 210 and the first magnetic detection element 11 are arranged in the opposing region of one thick part 2. The 2nd bus bar 220 is arrange | positioned in the opposing area | region of the other thick part 2 with the 2nd magnetic detection element 12. FIG. Therefore, the first magnetic detection element 11 and the second magnetic detection element 12 are arranged side by side in the X direction with the opposing region of the recess 1 interposed therebetween. Similarly, the first bus bar 210 and the second bus bar 220 are arranged side by side in the X direction across the opposing region of the recess 1.

Each component of the current sensor 100 and the bus bars 210 and 220 are arranged and assembled in this way. For example, each component of the current sensor 100 and the bus bars 210 and 220 have an assembly structure fixed to a housing or the like. The structure in which the bus bars 210 and 220, the magnetic detection elements 11 and 12, and the magnetic shields 21 and 22 are assembled can be referred to as a terminal block of the current sensor 100.

The detected current flows in the direction in which the bus bars 210 and 220 extend, that is, in the Y direction in FIG. Therefore, as shown in FIG. 2, the flow of the detected current in the Y direction generates a magnetic field according to the right-handed screw law on a plane orthogonal to the Y direction. This magnetic field can also be referred to as a detected magnetic flux. In the current sensor 100, each of the first magnetic detection element 11 and the second magnetic detection element 12 converts the detected magnetic flux into an electrical signal. That is, the first magnetic detection element 11 converts the detected magnetic flux flowing through the first bus bar 210 into an electrical signal. On the other hand, the second magnetic detection element 12 converts the detected magnetic flux flowing through the second bus bar 220 into an electrical signal. In this way, the current sensor 100 detects the detected current.

In addition, in this embodiment, as shown in FIG. 2, the case where the 1st bus bar 210 is an energized phase and the 2nd bus bar 220 is a detection phase is employ | adopted as an example. For this reason, when a current flows through the first bus bar 210, a magnetic flux flows through the magnetic shields 21 and 22, as indicated by solid arrows in FIG. Moreover, in this embodiment, the 1st bus bar 210 which is an electricity supply phase becomes a noise generation source.

Here, the effect of the current sensor 100 will be described in comparison with the current sensor of the comparative example. The current sensor of the comparative example employed here is not provided with the thin portion 3, and has a thick portion 2 that faces the first magnetic detection element 11 and a thick portion 2 that faces the second magnetic detection element 12. It is different from the current sensor 100 in that it is disconnected. For this reason, the same code | symbol as the component of the current sensor 100 is used for the component of the current sensor of a comparative example.

As in the case shown in FIG. 2, the current sensor of the comparative example has a dotted arrow in FIG. 2 from the end of the thick portion 2 facing the first magnetic detection element 11 when a current flows through the first bus bar 210. As shown in FIG. This end portion is an end portion on the thick portion 2 side facing the second magnetic detection element 12 in the thick portion 2 facing the first magnetic detection element 11.

When the leakage magnetic field is generated in this way, the second magnetic detection element 12 on the detection phase side is affected by the leakage magnetic field. For this reason, the current sensor 100 of the comparative example may cause an error in the detection result of the second magnetic detection element 12.

On the other hand, in the current sensor 100, the thick part 2 facing the first magnetic detection element 11 and the thick part 2 facing the second magnetic detection element 12 are connected via the thin part 3. The leakage magnetic field can be reduced as compared with the current sensor of the comparative example. Therefore, the second magnetic detection element 12 is not easily affected by the leakage magnetic field when detecting the detected current. For this reason, the current sensor 100 can suppress the occurrence of an error in the detection result of the second magnetic detection element 12. That is, the current sensor 100 can improve the detection accuracy of the second magnetic detection element 12 as compared with the current sensor of the comparative example.

Moreover, since the current sensor 100 is provided with the recess 1 in the first magnetic shield 21, the magnetic flux can flow on the outer surface of the first magnetic shield 21. That is, the current sensor 100 controls the magnetic flow path by providing the concave portion 1 in the first magnetic shield 21 so that the magnetic flux flows on the outer surface of the first magnetic shield 21.

For this reason, in the current sensor 100, the side opposite to the facing region side in the first magnetic shield 21, that is, the side far from the magnetic detection elements 11 and 12 in the first magnetic shield 21 is likely to be magnetically saturated. That is, the current sensor 100 can suppress magnetic saturation of the side near the magnetic detection elements 11 and 12 in the first magnetic shield 21. Therefore, the current sensor 100 can suppress the leakage magnetic field due to the magnetic saturation of the first magnetic shield 21 from affecting the magnetic detection elements 11 and 12.

Thus, the recess 1 is provided to control the magnetic flow path in the first magnetic shield 21. Therefore, the recessed part 1 can also be called a magnetic path control part.

In the present embodiment, the current sensor 100 including the two magnetic detection elements 11, 12, the first magnetic shield 21, and the second magnetic shield 22 is employed corresponding to the two- phase bus bars 210, 220. However, the present disclosure is not limited to this, and may include three magnetic detection elements, a first magnetic shield 21, and a second magnetic shield 22 corresponding to a three-phase bus bar. . In this case, the 1st magnetic shield 21 is provided with two thin parts provided between the three thick parts which oppose each of three magnetic detection elements, and the adjacent thick part.

Hereinafter, modifications 1 to 26 of the first embodiment will be described. The first embodiment and the modified examples 1 to 26 can be implemented independently, but can be implemented in combination as appropriate. The present disclosure is not limited to the combinations shown in the embodiments, and can be implemented by various combinations.

(Modification 1)
The current sensor 101 according to the first modification will be described with reference to FIG. The current sensor 101 is different from the current sensor 100 in the structure of the second magnetic shield 22A. FIG. 3 is a cross-sectional view corresponding to FIG.

The current sensor 101 includes a first magnetic shield 21A and a second magnetic shield 22A. Since the first magnetic shield 21A is the same as the first magnetic shield 21, description thereof is omitted.

On the other hand, the second magnetic shield 22A is provided with a thick portion 2A and a thin portion 3A, similarly to the first magnetic shield 21. The second magnetic shield 22 </ b> A is formed with a recess 1 </ b> A, similar to the first magnetic shield 21. That is, the second magnetic shield 22A includes a thick part 2A that faces the first bus bar 210, a thick part 2A that faces the second bus bar 220, and a thin part 3A that connects the two thick parts 2A. I have. The thick part 2A can be said to be an opposing base part. On the other hand, the thin portion 3A can be said to be an opposing connecting portion.

The current sensor 101 can achieve the same effects as the current sensor 100. Furthermore, since the second magnetic shield 22 </ b> A has the same configuration as the first magnetic shield 21, the same effect as that of the first magnetic shield 21 described above can be achieved. Therefore, the current sensor 101 can improve detection accuracy as compared with the current sensor 100. In addition, the current sensor 101 can easily maintain the shielding function of the second magnetic shield 22A, and can easily prevent the magnetic detection elements 11 and 12 from being affected by the magnetic saturation of the second magnetic shield 22A.

(Modification 2)
The current sensor 102 according to the second modification will be described with reference to FIG. The current sensor 102 differs from the current sensor 100 in the structure of the first magnetic shield 21B. 4 is a cross-sectional view corresponding to FIG.

The current sensor 102 includes a first magnetic shield 21B and a second magnetic shield 22B. Since the second magnetic shield 22B is the same as the second magnetic shield 22, description thereof is omitted.

The first magnetic shield 21 </ b> B includes two thick portions 2 and a thin portion 3 </ b> B connecting the two thick portions 2. The thin portion 3B corresponds to a connecting portion. The opposite surface and the opposite surface of the first magnetic shield 21B are flat surfaces in which a part that is recessed is formed. That is, the first magnetic shield 21 </ b> B is provided with the outer concave portion 1 </ b> B on the opposite side in addition to the concave portion 1. The current sensor 102 can achieve the same effect as the current sensor 100.

(Modification 3)
The current sensor 103 according to the third modification will be described with reference to FIG. The current sensor 103 is different from the current sensor 100 in the structure of the first magnetic shield 21C. 5 is a cross-sectional view corresponding to FIG.

The current sensor 103 includes a first magnetic shield 21C and a second magnetic shield 22C. Since the second magnetic shield 22C is the same as the second magnetic shield 22, description thereof is omitted.

The first magnetic shield 21 </ b> C includes two thick portions 2 and a lid portion 3 </ b> C that connects the two thick portions 2. In the first magnetic shield 21C, the two thick portions 2 are connected by the lid portion 3C to form the recess 1. The lid portion 3C corresponds to a connecting portion. As an example, the lid 3 </ b> C has a thickness in the Z direction that is thinner than the thick portion 2. The lid portion 3 </ b> C is connected to the opposite surfaces of the two thick portions 2. The current sensor 103 can achieve the same effect as the current sensor 100.

(Modification 4)
The current sensor 104 according to the fourth modification will be described with reference to FIG. The current sensor 104 is different from the current sensor 100 in the structure of the first magnetic shield 21D. 6 is a cross-sectional view corresponding to FIG.

The current sensor 104 includes a first magnetic shield 21D and a second magnetic shield 22D. Since the second magnetic shield 22D is the same as the second magnetic shield 22, description thereof is omitted.

The first magnetic shield 21D includes two base portions 2D and a projecting portion 3D that connects the two base portions 2D. The base portion 2D corresponds to the thick portion 2 of the above embodiment. The protruding part 3D corresponds to a connecting part.

The protruding portion 3D protrudes on the opposite surface side with respect to the base portion 2D. In other words, the protruding portion 3D is provided so as to protrude on the opposite side of the facing region in the first magnetic shield 21D. As an example, the protruding portion 3D includes a portion including a portion thinner than the base portion 2D between the connecting portion with the one base portion 2D and the connecting portion with the other base portion 2D. Yes. The thickness of the protrusion 3D is the thickness in the X direction at the portion extending in the Z direction and the thickness in the Z direction at the portion extending in the X direction. Therefore, the protrusion 3 </ b> D is a part having the same function as the thin part 3.

The first magnetic shield 21D has a recess 1 formed in the protrusion 3D. For this reason, the first magnetic shield 21 </ b> D can make the depth of the recess 1 in the Z direction deeper than the first magnetic shield 21. For this reason, the recess 1 is formed deeper than the thickness of the first magnetic shield 21. That is, in the first magnetic shield 21D, the length in the Z direction from the virtual plane along the facing surface to the bottom of the recess 1 is longer than the thickness in the Z direction of the base portion 2D.

The current sensor 104 can achieve the same effect as the current sensor 100. Furthermore, since the concave portion 1 is deeper than the concave portion 1 of the current sensor 100 in the current sensor 104, it is easy to place the component 30 in the concave portion 1. Further, when the electronic component 30 is disposed in the recess 1, the current sensor 104 has a mechanical shielding function for the electronic component 30, and does not need to protect the electronic component with a protective member such as a gel. Therefore, the current sensor 104 can reduce the number of manufacturing processes and can be expected to reduce the cost.

(Modification 5)
With reference to FIG. 7, the current sensor 105 of Modification 5 will be described. The current sensor 105 is different from the current sensor 100 in the structure of the first magnetic shield 21E. 7 is a cross-sectional view corresponding to FIG.

The current sensor 105 includes a first magnetic shield 21E and a second magnetic shield 22E. Since the second magnetic shield 22E is the same as the second magnetic shield 22, the description thereof is omitted.

The first magnetic shield 21E includes two thick portions 2 and a thin portion 3B that connects the two thick portions 2. And the recessed part 1 is formed in the 1st magnetic shield 21E. More specifically, the first magnetic shield 21E has a recess 1 whose side wall is an inclined portion 1E. Therefore, the recessed area 1 of the first magnetic shield 21E has an opening area that increases from the bottom of the recessed section 1 toward the opening end.

Note that the concave portion 1 of the first magnetic shield 21E is formed by pressing. Therefore, the 1st magnetic shield 21E can form the inclination part 1E by providing the metal mold | die of a press machine with the inclination.

The current sensor 105 can achieve the same effect as the current sensor 100. Furthermore, since the side wall of the recessed part 1 is the inclined part 1E, the current sensor 105 can easily remove the mold from the recessed part 1 during press working.

(Modification 6)
The current sensor 106 according to Modification 6 will be described with reference to FIG. The current sensor 106 is different from the current sensor 105 in the structure of the first magnetic shield 21F. FIG. 8 is a cross-sectional view corresponding to FIG.

The current sensor 106 includes a first magnetic shield 21F and a second magnetic shield 22F. Since the second magnetic shield 22F is the same as the second magnetic shield 22E, description thereof is omitted.

The first magnetic shield 21F includes two base portions 2F and a projecting portion 3F connecting the two base portions 2F. The base portion 2F corresponds to the thick portion 2 of the above embodiment. The protruding part 3F corresponds to a connecting part. And the 1st magnetic shield 21F has the recessed part 1 whose side wall is the inclined part 1F similarly to the 1st magnetic shield 21E.

Thus, the first magnetic shield 21F is different from the first magnetic shield 21E mainly in that the protruding portion 3F protrudes on the opposite surface side. Further, the concave portion 1 of the first magnetic shield 21F can be formed by pressing as in the fifth modification.

The current sensor 106 can achieve the same effect as the current sensor 105. Furthermore, the current sensor 106 can be easily manufactured by pressing because the protruding portion 3F protrudes on the opposite surface side.

(Modification 7)
The current sensor 107 according to the modified example 7 will be described with reference to FIG. The current sensor 107 is different from the current sensor 100 in the structure of the first magnetic shield 21G. FIG. 9 is a cross-sectional view corresponding to FIG.

The current sensor 107 includes a first magnetic shield 21G and a second magnetic shield 22G. Since the second magnetic shield 22F is the same as the second magnetic shield 22E, description thereof is omitted.

The first magnetic shield 21G has a recess 1 formed in the vicinity of the first bus bar 210 and in the vicinity of the second bus bar 220. Specifically, the recess 1 is formed at a position facing the first bus bar 210 and a position facing the second bus bar 220. That is, the recess 1 is formed at a position facing each of the magnetic detection elements 11 and 12. The first magnetic shield 21 </ b> G is provided with a heat radiating gel 40 in the recess 1. The heat radiating gel 40 corresponds to a heat radiating member.

The current sensor 107 can achieve the same effect as the current sensor 100. Further, the current sensor 107 is provided with a heat radiating gel 40 in the vicinity of the bus bars 210, 220 in the first magnetic shield 21G, here, at a position facing the bus bars 210, 220. For this reason, the current sensor 107 easily transfers the heat generated by the bus bars 210 and 220 to the first magnetic shield 21G via the heat dissipation gel 40. Furthermore, since the thermal sensor 40 is provided in the recessed part 1, the current sensor 107 can improve the mechanical strength of the first magnetic shield 21G as compared with the case where the recessed part 1 is a space.

Further, the current sensor 107 may be provided with the concave portion 1 at a position facing the bus bars 210 and 220 in the second magnetic shield 22G, and the heat radiation gel 40 may be disposed in the concave portion 1. In this case, the current sensor 107 can further improve the heat dissipation. Moreover, the current sensor 107 can improve the mechanical strength of the second magnetic shield 22G by disposing the heat radiating gel 40 in the concave portion 1 as compared with the case where the concave portion is a space in the second magnetic shield 22G.

(Modification 8)
The current sensor 108 according to Modification 8 will be described with reference to FIGS. 10 and 11. The current sensor 108 is different from the current sensor 100 in the structure of the first magnetic shield 21G. Current sensor 108 is different from current sensor 100 in that it is configured as a four-phase sensor. FIG. 10 is a cross-sectional view corresponding to FIG.

The current sensor 108 includes a first sensor block 108A, a second sensor block 108B, a third sensor block 108C, and a fourth sensor block 108D. The current sensor 108 is configured by assembling a plurality of sensor blocks 108A to 108D. Further, it can be said that the current sensor 108 is modularized by connecting a plurality of sensor blocks 108A to 108D. Each of the sensor blocks 108A to 108D has the same configuration.

Here, the configuration of each of the sensor blocks 108A to 108D will be described with reference to FIG. Here, the first sensor block 108A will be described as a representative example.

The first sensor block 108A includes the magnetic detection element 11, the bus bar 210, the first magnetic shield 21H, the second magnetic shield 22H, and the sealing resin portion 50. The bus bar 210 of the first sensor block 108A can be said to be the first bus bar 210 in which the current of the first phase flows. Further, it can be said that the magnetic detection element 11 of the first sensor block 108A is the first magnetic detection element 11 that detects the current of the first phase.

Each of the first magnetic shield 21H and the second magnetic shield 22H is made of a magnetic material. The first magnetic shield 21H and the second magnetic shield 22H are configured as plate-like members orthogonal to the Z direction. The first magnetic shield 21H and the second magnetic shield 22H are disposed to face each other with an interval in the Z direction.

Also, the first magnetic shield 21H and the second magnetic shield 22H are arranged so as to sandwich the magnetic detection element 11 and the bus bar 210 in the Z direction. Therefore, it can be said that the magnetic detection element 11 and the bus bar 210 are disposed in the opposing region of the first magnetic shield 21H and the second magnetic shield 22H. The first magnetic detection element 11 faces the first magnetic shield 21H without the bus bar 210 interposed therebetween, and faces the second magnetic shield 22H with the bus bar 210 interposed therebetween.

In the present embodiment, the first magnetic shield 21H and the second magnetic shield 22H having the same shape are employed. The first magnetic shield 21H and the second magnetic shield 22H are flat plate-like plate members. The first magnetic shield 21H has a first opposing surface S2 that is an opposing surface to the second magnetic shield 22H, and a first opposing surface S1 that is an opposite surface of the first opposing surface S2. On the other hand, the second magnetic shield 22H has a second opposing surface S4 that is an opposing surface to the first magnetic shield 21H, and a second opposing surface S3 that is an opposite surface of the second opposing surface S4.

In the first magnetic shield 21H and the second magnetic shield 22H, the first opposite surface S1, the first opposite surface S2, the second opposite surface S3, and the second opposite surface S4 are flat surfaces. Further, the first magnetic shield 21H and the second magnetic shield 22H have a uniform thickness in the Z direction over the entire area.

In the first sensor block 108A, the first magnetic detection element 11, the first bus bar 210, the first magnetic shield 21H, and the second magnetic shield 22H are integrally configured by the sealing resin portion 50. The first magnetic detection element 11 and the first bus bar 210 are sealed with a sealing resin portion 50 in a state where the first magnetic detection element 11 and the first bus bar 210 are arranged in the opposing region of the magnetic shield 21H and the second magnetic shield 22H. Note that both ends of the first bus bar 210 in the Y direction are exposed from the sealing resin portion 50. The magnetic shield 21H and the second magnetic shield 22H are fixed to the sealing resin portion 50.

The first magnetic shield 21H and the second magnetic shield 22H include regions where the sealing resin portion 50 is not formed at both ends in the X direction. This is because adjacent sensor blocks are connected by the first magnetic shield 21H and the second magnetic shield 22H.

The second sensor block 108B includes a second bus bar 220 through which a second-phase current flows as a bus bar, and a second magnetic detection element 12 that detects a second-phase current as a magnetic detection element. Similarly, the third sensor block 108C includes a third bus bar 230 through which a third-phase current flows as a bus bar, and a third magnetic detection element 13 that detects a third-phase current as a magnetic detection element. The fourth sensor block 108D includes a fourth bus bar 240 through which a fourth-phase current flows as a bus bar, and a fourth magnetic detection element 14 that detects a fourth-phase current as a magnetic detection element. The bus bars 230 and 240 correspond to current paths.

In the present embodiment, as an example, the current sensor 108 arranged in the order of the first sensor block 108A, the second sensor block 108B, the third sensor block 108C, and the fourth sensor block 108D is employed. The current sensor 108 is assembled in a state where the second sensor block 108B and the fourth sensor block 108D are turned upside down with respect to the first sensor block 108A and the third sensor block 108C. Therefore, the current sensor 108 is assembled with a plurality of sensor blocks 108A to 108D so that the first magnetic shield 21H and the second magnetic shield 22H of adjacent sensor blocks are in contact with each other.

That is, in the current sensor 108, the first magnetic shield 21H of the first sensor block 108A and the second magnetic shield 22H of the second sensor block 108B are in contact with each other, and the second magnetic shield 22H of the first sensor block 108A and the second sensor block 108A are in contact. The first magnetic shield 21H of 108B is in contact. The current sensor 108 is in contact with the second facing surface S4 of the first sensor block 108A and the first opposite surface S1 of the second sensor block 108B, and the first opposite surface S1 of the first sensor block 108A and the second sensor block 108A. 108B 2nd opposing surface S4 is assembled | attached in contact. These contact portions are portions where the sealing resin portion 50 is not provided in the first magnetic shield 21H and the second magnetic shield 22H.

In the current sensor 108, the first magnetic shield 21H of the second sensor block 108B and the second magnetic shield 22H of the third sensor block 108C are in contact with each other, and the second magnetic shield 22H of the second sensor block 108B and the third sensor block 108B are in contact. The first magnetic shield 21H of 108C is in contact. The current sensor 108 is in contact with the first opposite surface S1 of the second sensor block 108B and the second opposite surface S4 of the third sensor block 108C, and the second opposite surface S4 of the second sensor block 108B and the third sensor block 108B. 108C 1st opposing surface S1 is contact | attached and assembled | attached.

Further, the current sensor 108 is in contact with the first magnetic shield 21H of the third sensor block 108C and the second magnetic shield 22H of the fourth sensor block 108D, and the second magnetic shield 22H of the third sensor block 108C and the fourth sensor block 108C. The first magnetic shield 21H of 108D is in contact. The current sensor 108 is in contact with the second opposing surface S4 of the third sensor block 108C and the first opposite surface S1 of the fourth sensor block 108D, and the first opposite surface S1 of the third sensor block 108C and the fourth sensor block. 108D 2nd opposing surface S4 is assembled | attached in contact.

The current sensor 108 is integrated by connecting these contacting parts. In addition, the code | symbol 21H1 in FIG. 10 is a connection part in an upper magnetic shield. On the other hand, reference numeral 22H1 is a connecting portion in the lower magnetic shield. In addition, the magnetic shield in which the second magnetic shield 22H of the first sensor block 108A and the third sensor block 108C and the first magnetic shield 21H of the second sensor block 108B and the fourth sensor block 108D are integrated is an upper magnetic shield. It can be called a shield. On the other hand, the magnetic shield in which the first magnetic shield 21H of the first sensor block 108A and the third sensor block 108C and the second magnetic shield 22H of the second sensor block 108B and the fourth sensor block 108D are integrated is the lower side. It can be called a magnetic shield.

The current sensor 108 is formed such that the second magnetic shield 22H of the first sensor block 108A or the third sensor block 108C is recessed with respect to the first magnetic shield 21H of the second sensor block 108B or the fourth sensor block 108D. . Similarly, the current sensor 108 is formed such that the second magnetic shield 22H of the second sensor block 108B or the fourth sensor block 108D is recessed with respect to the first magnetic shield 21H of the first sensor block 108A or the third sensor block 108C. Has been. In the current sensor 108, the sensor blocks 108A to 108D are assembled as described above, so that it can be said that the concave portion 1 recessed from the periphery is formed on the surface facing the other magnetic shield.

The current sensor 108 can achieve the same effect as the current sensor 100. That is, the current sensor 108 has a configuration in which adjacent sensor blocks, for example, the first sensor block 108A and the second sensor block 108B are connected by the first magnetic shield 21H and the second magnetic shield 22H. For this reason, the current sensor 108 can suppress the leakage magnetic field.

Further, since the current sensor 108 is formed with the recess 1, a magnetic field is generated in the first magnetic shield 21 </ b> H and the second magnetic shield 22 </ b> H as indicated by a straight arrow extending in the X direction in FIG. 10. That is, the current sensor 108 can cause the magnetic flux to flow on the outer surface of the first magnetic shield 21H. In other words, the current sensor 108 can control the magnetic flow path so as to flow on the surface of the first magnetic shield 21H on the side far from the magnetic detection elements 11-14. For this reason, each of the magnetic detection elements 11 to 14 is not easily affected by the leakage magnetic field due to magnetic saturation.

Furthermore, in the current sensor 108, each of the sensor blocks 108A to 108D has the same configuration. That is, the sensor blocks 108A to 108D are standardized. As described above, the current sensor 108 is configured by assembling the standardized sensor blocks 108A to 108D, so that the cost can be reduced. The current sensor 108 can also be implemented in combination with the modified example 7, and the heat radiating gel 40 may be embedded in the recess 1.

(Modification 9)
The current sensor 109 according to the modified example 9 will be described with reference to FIG. The current sensor 109 differs from the current sensor 101 in the number of magnetoresistive elements and the positions of the recesses 1 and 1A. FIG. 12 is a cross-sectional view corresponding to FIG.

The current sensor 109 includes one first magnetic detection element 11, a first magnetic shield 21I, and a second magnetic shield 22I. The first magnetic detection element 11 is located at a position facing the first bus bar 210 and is disposed in a facing region between the first magnetic shield 21I and the second magnetic shield 22I. Specifically, the first magnetic detection element 11 and the first bus bar 210 are arranged at a position where the central thick part 2 of the first magnetic shield 21I and the thick part 2A of the second magnetic shield 22I face each other. Has been.

The first magnetic shield 21I includes three thick portions 2 and two thin portions 3. Therefore, the first magnetic shield 21I has the recesses 1 formed in two places. The second magnetic shield 22I is the same as the first magnetic shield 21I. In the current sensor 109, the concave portion 1 of the first magnetic shield 21I and the concave portion 1A of the second magnetic shield 22I are arranged to face each other. Thus, the current sensor 109 is configured as a one-phase sensor.

The current sensor 109 has a recess 1 formed in the first magnetic shield 21I. For this reason, in the current sensor 109, the disturbance magnetic field flows on the outer surface of the first magnetic shield 21I. Therefore, like the current sensor 100, the current sensor 109 can suppress the influence of magnetic saturation from occurring in the first magnetic detection element 11. In addition, since the current sensor 109 has the recess 1A formed in the second magnetic shield 22I, it is possible to further suppress the influence of magnetic saturation on the first magnetic detection element 11.

Note that the current sensor 109 may employ the second magnetic shield 22 or the second magnetic shield 22A instead of the second magnetic shield 22I.

(Modification 10)
The current sensor 110 according to the tenth modification will be described with reference to FIG. The current sensor 110 is different from the current sensor 101 in the configuration of the first magnetic shield 21J and the second magnetic shield 22J. FIG. 13 is a cross-sectional view corresponding to FIG.

The first magnetic shield 21J is formed by laminating a plurality of layers made of a magnetic material. In this modification, a first magnetic shield 21J in which a first surface layer 21J1, a first intermediate layer 21J2, and a first facing layer 21J3 are stacked is employed. The first surface layer 21J1 is a single flat plate member. On the other hand, the first intermediate layer 21J2 and the first opposing layer 21J3 are two flat plate members.

The thick part 2 of the first magnetic shield 21J is configured by laminating a first surface layer 21J1, a first intermediate layer 21J2, and a first opposing layer 21J3. Further, the thick part 2 of the first magnetic shield 21J is laminated in the order of the first facing layer 21J3, the first intermediate layer 21J2, and the first surface layer 21J1 from the second magnetic shield 22J side.

The thin portion 3 of the first magnetic shield 21J is not provided with the first opposing layer 21J3 and the first intermediate layer 21J2, but is constituted by the first surface layer 21J1. That is, in the first magnetic shield 21J, each of the first intermediate layer 21J2 and the first opposing layer 21J3 is divided in order to form the recess 1.

Further, the second magnetic shield 22J is formed by laminating a plurality of layers made of a magnetic material. In this modification, a second magnetic shield 22J in which a second surface layer 22J1, a second intermediate layer 22J2, and a second opposing layer 22J3 are stacked is employed. The layers 22J1 to 22J3 of the second magnetic shield 22J correspond to the layers 21J1 to 21J3 of the first magnetic shield 21J.

The current sensor 110 can achieve the same effect as the current sensor 101. Note that the current sensor 110 may employ the second magnetic shield 22 or the second magnetic shield 22A instead of the second magnetic shield 22J.

Furthermore, the current sensor 110 may use materials having different magnetic permeability between the first surface layer 21J1, the first intermediate layer 21J2, and the first opposing layer 21J3. Similarly, the current sensor 110 may use materials having different magnetic permeability between the second surface layer 22J1, the second intermediate layer 22J2, and the second facing layer 22J3.

The first surface layer 21J1 and the second surface layer 22J1 are made of a material having a magnetic permeability μA. On the other hand, the first intermediate layer 21J2, the first counter layer 21J3, the second intermediate layer 22J2, and the second counter layer 22J3 are made of a material having a magnetic permeability μB. The relationship between μA and μB is μA> μB. The first surface layer 21J1 and the second surface layer 22J1 correspond to the outermost layer on the opposite side of the facing region.

In the current sensor 110 configured in this way, magnetic flux is more likely to collect in the first surface layer 21J1 and the second surface layer 22J1 made of a material having low magnetic resistance than the other layers, and the other layers are less likely to be magnetically saturated. Become. That is, in the current sensor 110, the thick portions 2 and 2A are less likely to be magnetically saturated. Moreover, since the thin- walled portions 3 and 3A have a lower magnetic resistance than the thick- walled portions 2 and 2A, the leakage magnetic field in the recesses 1 and 1A can be suppressed. The other layers are the first intermediate layer 21J2, the first counter layer 21J3, the second intermediate layer 22J2, and the second counter layer 22J3.

Furthermore, the current sensor 110 may use materials having different saturation magnetic flux densities in the first surface layer 21J1, the first intermediate layer 21J2, and the first opposing layer 21J3. Similarly, the current sensor 110 may use materials having different saturation magnetic flux densities in the second surface layer 22J1, the second intermediate layer 22J2, and the second facing layer 22J3.

The first surface layer 21J1 and the second surface layer 22J1 are made of a material having a saturation magnetic flux density BsA. On the other hand, the first intermediate layer 21J2, the first counter layer 21J3, the second intermediate layer 22J2, and the second counter layer 22J3 are made of a material having a saturation magnetic flux density BsB. The relationship between BsA and BsB is BsA> BsB.

In the current sensor 110 configured in this way, the first surface layer 21J1 and the second surface layer 22J1 are less likely to be magnetically saturated than the other layers, so that a relatively large current flows through the first bus bar 210 and the second bus bar 220. Even in this case, the leakage magnetic field from the recesses 1 and 1A can be suppressed.

(Modification 11)
The current sensor 111 according to the modification 11 will be described with reference to FIG. The current sensor 111 is different from the current sensor 110 in the configuration of the second magnetic shield 22K. 14 is a cross-sectional view corresponding to FIG.

The first magnetic shield 21K is configured by laminating a first surface layer 21K1, a first intermediate layer 21K2, and a first opposing layer 21K3, similarly to the first magnetic shield 21J. As each of the layers 21K1 to 21K3 of the first magnetic shield 21K, for example, the one shown in the modified example 10 can be adopted.

The second magnetic shield 22K is configured by laminating a second surface layer 22K1, a second intermediate layer 22K2, and a second opposing layer 22K3, similarly to the second magnetic shield 22J. Further, each layer 22K1 to 22K3 of the second magnetic shield 22K is held by a resinous housing 22K4. In other words, each layer 22K1 to 22K3 of the second magnetic shield 22K is covered with the housing 22K4.

Therefore, the second surface layer 22K1 and the second facing layer 22K3 have a larger area in contact with the housing 22K4 than the second intermediate layer 22K2. The second surface layer 22K1 corresponds to the outermost layer on the opposite side of the facing region. The second facing layer 22K3 corresponds to the outermost layer on the facing region side.

The first bus bar 210 and the second bus bar 220 are mounted on the housing 22K4. The housing 22K4 corresponds to a resin member.

In the second magnetic shield 22K, the linear expansion coefficients of the constituent elements 22K1 to 22K4 are set as follows. The linear expansion coefficient of the second surface layer 22K1 and the second opposing layer 22K3 is αA, the linear expansion coefficient of the second intermediate layer 22K2 is αB, and the linear expansion coefficient of the housing 22K4 is αC. The relationship between the linear expansion coefficients αA to αC is | αA−αC | <| αB−αC |.

The current sensor 111 can achieve the same effect as the current sensor 100. Further, in the current sensor 111, the relationship of the linear expansion coefficient between the housing 22K4 and each of the layers 22K1 to 22K3 is as described above, so that the interface between the housing 22K4 and the second surface layer 22K1, the housing 22K4 and the second facing layer 22K3. Can be prevented from peeling at the interface.

(Modification 12)
The current sensor 112 according to the modification 12 will be described with reference to FIGS. 15 and 16. The current sensor 112 is different from the current sensor 110 in the configuration of the first magnetic shield 21L and the second magnetic shield 22L.

The first magnetic shield 21L is configured by laminating a first surface layer 21L1, a first intermediate layer 21L2, and a first opposing layer 21L3, like the first magnetic shield 21J. As each of the layers 21L1 to 21L3 of the first magnetic shield 21L, for example, the one shown in the modified example 10 can be adopted.

However, in the first magnetic shield 21L, the recess 1 does not reach both ends in the Y direction, as shown in FIG. That is, in the first magnetic shield 21L, a bottomed hole portion surrounded by the bottom portion and the annular side wall is formed as the concave portion 1. Therefore, in the first magnetic shield 21L, portions 3E having the same thickness as the thick portion 2 are formed on both sides of the recess 1 in the Y direction. This portion 3E corresponds to the beam portion 3E. For this reason, it can be said that the first magnetic shield 21 </ b> L has the beam portions 3 </ b> E provided continuously with the two thick portions 2 on both sides of the recess 1.

Further, the second magnetic shield 22L is configured by laminating a first surface layer 22L1, a first intermediate layer 22L2, and a first facing layer 22L3, similarly to the second magnetic shield 22J. As each of the layers 22L1 to 22L3 of the second magnetic shield 22L, for example, the one shown in the modified example 10 can be adopted. The second magnetic shield 22L, like the first magnetic shield 21L, has the recessed portion 1A that does not reach both ends in the Y direction and has a beam portion 3E.

The current sensor 112 can achieve the same effect as the current sensor 110. Furthermore, since the concave portions 1 and 1A do not reach both ends in the Y direction, the current sensor 112 can improve the mechanical strength as compared with the current sensor 110.

(Modification 13)
With reference to FIG. 17, the current sensor 113 of Modification 13 will be described. Current sensor 113 is different from current sensor 101 in that it includes an upper phase 113A and a lower phase 113B. FIG. 17 is a cross-sectional view corresponding to FIG.

In the current sensor 113, an upper phase in which the two bus bars 210 and 220 are arranged and a lower phase in which the two bus bars 230 and 240 are arranged are stacked in the thickness direction (Z direction) of the first magnetic shield 21A. Yes. The current sensor 113 has the same configuration as the current sensor 101 described in Modification 1 as an upper phase 113A and a lower phase 113B. That is, the current sensor 113 has a configuration in which the two current sensors 101 are integrally assembled.

Therefore, the current sensor 113 is provided so as to face the two magnetic detection elements 11 and 12 provided to face the bus bars 210 and 220 in the upper phase 113A, and to the bus bars 230 and 240 in the lower phase 113B, respectively. The two magnetic detection elements 13 and 14 are provided. The current sensor 113 includes two magnetic shields 21A and 22A that sandwich the bus bars 210 and 220 and the magnetic detection elements 11 and 12 in the upper phase 113A. Furthermore, the current sensor 113 includes two magnetic shields 21A and 22A that sandwich the bus bars 230 and 240 and the magnetic detection elements 13 and 14 in the lower phase 113B.

In the current sensor 113, the second magnetic shield 22A of the upper phase 113A and the first magnetic shield 21A of the lower phase 113B are arranged to face each other. Specifically, the opposite surface of the second magnetic shield 22A in the upper phase 113A and the opposite surface of the first magnetic shield 21A in the lower phase 113B are arranged to face each other. Thus, the current sensor 113 is configured as a four-phase sensor.

The second magnetic shield 22A of the upper phase 113A and the first magnetic shield 21A of the lower phase 113B can be said to be intermediate magnetic shields. The thick part 2A of the second magnetic shield 22A in the upper phase 113A and the thick part 2 of the first magnetic shield 21A in the lower phase 113B can be said to be intermediate base parts. Further, the thin portion 3A of the second magnetic shield 22A in the upper phase 113A and the thin portion 3 of the first magnetic shield 21A in the lower phase 113B can be said to be intermediate coupling portions.

The current sensor 113 can achieve the same effect as the current sensor 101. Further, since the current sensor 113 includes the second magnetic shield 22A of the upper phase 113A and the first magnetic shield 21A of the lower phase 113B as intermediate magnetic shields, magnetic interference between the upper phase 113A and the lower phase 113B. Can be relaxed. For example, when the upper phase 113A has an energized phase and the upper phase 113A has a detection phase, the current sensor 113 can reduce the leakage magnetic field from the upper phase 113A to the lower phase 113B.

In this modification, the present invention is not limited to this, and three or more bus bars may be arranged in the upper phase 113A, and three or more bus bars may be arranged in the lower phase 113B. In this case, in the upper phase 113A, a magnetic detection element is arranged to face each of the bus bars. Similarly, in the lower phase 113B, magnetic detection elements are arranged to face the respective bus bars.

(Modification 14)
The current sensor 114 according to the modified example 14 will be described with reference to FIG. The current sensor 114 is different from the current sensor 113 in the positional relationship between the magnetic detection elements 13 and 14 and the bus bars 230 and 240 in the lower phase 114B. 18 is a cross-sectional view corresponding to FIG.

The current sensor 114 includes an upper phase 114A and a lower phase 114B. The upper phase 114A is the same as the upper phase 113A. On the other hand, in the lower phase 114B, unlike the lower phase 113B, the magnetic detection elements 13 and 14 are disposed on the second magnetic shield 22A side, and the bus bars 230 and 240 are disposed on the first magnetic shield 21A side. The current sensor 114 can achieve the same effect as the current sensor 113.

(Modification 15)
The current sensor 115 according to the modification 15 will be described with reference to FIG. The current sensor 115 is different from the current sensor 113 in that the intermediate magnetic shield 23 is configured as an integral body. FIG. 19 is a cross-sectional view corresponding to FIG.

The current sensor 115 includes an upper phase 115A and a lower phase 115B. The intermediate magnetic shield 23 includes two thick portions 5 and a thin portion 6 that connects the two thick portions 5.

The intermediate magnetic shield 23 includes a thick part 5 that faces the first magnetic detection element 11 and the third magnetic detection element 13, and a thick part 5 that faces the second magnetic detection element 12 and the fourth magnetic detection element 14. I have. In other words, the intermediate magnetic shield 23 includes the thick part 5 on the first magnetic detection element 11 and the third magnetic detection element 13 side, and the thick part 5 on the second magnetic detection element 12 and the fourth magnetic detection element 14 side. It has. The intermediate magnetic shield 23 has a facing surface that faces the first magnetic shield 21A on the upper phase 115A side and a facing surface that faces the second magnetic shield 22A on the lower phase 115B side. The thick part 5 can be said to be an intermediate base part. It can be said that the thin part 6 is an intermediate | middle connection part.

Further, the intermediate magnetic shield 23 includes the thick portion 5 and the thin portion 6 so that the concave portion 4 opened on the upper phase 115A side and the concave portion 4 opened on the lower phase 115B side are formed. As described above, the intermediate magnetic shield 23 can be regarded as a single body of the second magnetic shield 22A of the upper phase 113A and the first magnetic shield 21A of the lower phase 113B in Modification 13.

The current sensor 115 can achieve the same effect as the current sensor 113. Furthermore, since the intermediate magnetic shield 23 is configured as an integrated object in the current sensor 115, the size of the current sensor 115 in the Z direction can be reduced. That is, the current sensor 115 can be made smaller than the current sensor 113 in which the second magnetic shield 22A of the upper phase 113A and the first magnetic shield 21A of the lower phase 113B are intermediate magnetic shields.

(Modification 16)
The current sensor 116 according to the modified example 16 will be described with reference to FIG. Current sensor 116 is different from current sensor 115 in the positional relationship between magnetic detection elements 13 and 14 and bus bars 230 and 240 in lower phase 116B. 20 is a cross-sectional view corresponding to FIG.

The current sensor 116 includes an upper phase 116A and a lower phase 116B. The upper phase 116A is the same as the upper phase 115A. On the other hand, in the lower phase 116B, unlike the lower phase 115B, the magnetic detection elements 13 and 14 are disposed on the second magnetic shield 22A side, and the bus bars 230 and 240 are disposed on the intermediate magnetic shield 23 side. The current sensor 116 can achieve the same effect as the current sensor 115.

(Modification 17)
The current sensor 117 according to the modified example 17 will be described with reference to FIG. The current sensor 117 is different from the current sensor 115 in the configuration of the intermediate magnetic shield 24. FIG. 21 is a cross-sectional view corresponding to FIG.

The current sensor 117 includes an upper phase 117A and a lower phase 117B. The intermediate magnetic shield 24 includes two base portions 5A and a thin portion 6 that connects the two base portions 5A. The intermediate magnetic shield 23 includes a base portion 5A that faces the first magnetic detection element 11 and the third magnetic detection element 13, and a base portion 5A that faces the second magnetic detection element 12 and the fourth magnetic detection element 14. Yes. In other words, the intermediate magnetic shield 23 includes a base portion 5A on the first magnetic detection element 11 and third magnetic detection element 13 side, and a base portion 5A on the second magnetic detection element 12 and fourth magnetic detection element 14 side. ing. The base portion 5A can be said to be an intermediate base portion. It can be said that the thin part 6 is an intermediate | middle connection part.

The base portion 5A is formed with a space portion 7 penetrating in the Y direction. That is, it can be said that the intermediate magnetic shield 23 is provided with the space portion 7 in a region where the bus bars 210 and 220 on the upper phase 117A side and the bus bars 230 and 240 on the lower phase 117B side face each other. The space portion 7 corresponds to a nonmagnetic portion. The space 7 may be filled with a nonmagnetic material.

The intermediate magnetic shield 24 has a facing surface that faces the first magnetic shield 21A on the upper phase 117A side, and a facing surface that faces the second magnetic shield 22A on the lower phase 117B side. The interval between the opposing surfaces in the base portion 5 </ b> A is longer than the thickness of the thin portion 6 in the Z direction.

The current sensor 117 can achieve the same effect as the current sensor 115. Furthermore, since the space portion 7 is formed in the intermediate magnetic shield 24, the current sensor 117 can control the magnetic flow path in the intermediate magnetic shield 24.

(Modification 18)
The current sensor 118 according to the modified example 18 will be described with reference to FIG. The current sensor 118 differs from the current sensor 117 in the positional relationship between the magnetic detection elements 13 and 14 and the bus bars 230 and 240 in the lower phase 118B. FIG. 22 is a cross-sectional view corresponding to FIG.

The current sensor 118 includes an upper phase 118A and a lower phase 118B. The upper phase 118A is the same as the upper phase 117A. On the other hand, in the lower phase 118B, unlike the lower phase 117B, the magnetic detection elements 13 and 14 are disposed on the second magnetic shield 22A side, and the bus bars 230 and 240 are disposed on the intermediate magnetic shield 24 side. The current sensor 118 can achieve the same effect as the current sensor 117.

(Modification 19)
The current sensor 119 according to the modification 19 will be described with reference to FIGS. The current sensor 119 is different from the current sensor 101 in that it includes three magnetic detection elements 11 to 13 and the shape of the first magnetic shield 21M. Further, unlike the modification 13 and the like, the current sensor 119 does not have a configuration in which an upper phase and a lower phase are stacked. In other words, the current sensor 119 is a single-phase structure current sensor. Note that the current sensors after the modification 20 described later are also single-phase current sensors.

In this modification, as an example, an inverter that converts DC power into three-phase AC power and a current sensor 119 that is mounted on the vehicle together with a motor generator that is driven by the three-phase AC power from the inverter are employed. Current sensor 119 detects a current flowing between the inverter and the motor generator. More specifically, the current sensor 119 individually detects the current flowing through each of the three bus bars 210 to 230 that electrically connect the inverter and the motor generator.

As will be described later, the current sensor 119 includes three phases P1 to P3. Each of the phases P1 to P3 is provided corresponding to each phase between the inverter and the motor generator. Each of the phases P1 to P3 includes one magnetic detection element, a part of the first magnetic shield 21M, and a part of the second magnetic shield 22M. Here, the first magnetic detection element 11 is the magnetic detection element of the first phase P1, the second magnetic detection element 12 is the magnetic detection element of the second phase P2, and the third magnetic detection element 13 is the magnetic detection of the third phase P3. A detection element is used.

The current sensor 119 includes a second magnetic shield 22M, magnetic detection elements 11 to 13, and a first magnetic shield 21M stacked in this order in the Z direction. Therefore, it can be said that the Z direction is also a stacking direction.

First, the three bus bars 210 to 230 will be described. The three bus bars 210 to 230 have, for example, a shape in which a plate-like conductive member is bent. Of the three bus bars 210 to 230, the first bus bar 210 can be said to be the bus bar for the first phase P1, the second bus bar 220 can be said to be the bus bar for the second phase P2, and the third bus bar 230 can be said to be the bus bar for the third phase P3. In this modification, as shown in FIG. 23, three bus bars 210 to 230 having different shapes are employed. This is because the distance between the terminals of the motor generator is different from the distance between the terminals of the inverter.

The first bus bar 210 includes a first end portion 211 that is an end portion on the motor generator side, a second end portion 212 that is an end portion on the inverter side, a facing portion 213, a bent portion 214, A first extension 215 and a second extension 216 are included. The opposed portion 213 is a portion disposed in a facing region between the first magnetic shield 21M and the second magnetic shield 22M. Further, the opposed portion 213 is a portion facing the first magnetic detection element 11. Therefore, the first magnetic detection element 11 is provided in a facing region between the opposed portion 213 and the first magnetic shield 21M.

The bent portion 214 is a portion bent in the Z direction from the opposed portion 213. The first extension portion 215 and the second extension portion 216 are portions for connecting the bent portion 214 and the second end portion 212. As shown in FIG. 23, since the first bus bar 210 includes the first extension 215 and the second extension 216, the first bus bar 210 is provided to reach the region on the Y direction side in the second phase P2.

The second bus bar 220 includes a first end 221 that is an end portion on the motor generator side, a second end portion 222 that is an end portion on the inverter side, and a facing portion 223, a bent portion 224, and an extension between both ends. Part 225 is included. Further, the opposed part 223 is a part facing the second magnetic detection element 12. Therefore, the second magnetic detection element 12 is provided in a facing region between the opposed portion 223 and the first magnetic shield 21M.

The second bus bar 220 is different from the first bus bar 210 in the configuration (length) of the extension 225. As shown in FIG. 23, since the second bus bar 220 includes the extension 225, the second bus bar 220 is provided to reach the region on the Y direction side in the third phase P3.

Third bus bar 230 includes a first end 231 that is an end on the motor generator side, a second end 232 that is an end on the inverter side, and a facing portion 233 and a bent portion 234 between both ends. It is out. As described above, the third bus bar 230 is different from the first bus bar 210 and the second bus bar 220 in that the bent portion 234 and the second end portion 232 are connected without an extension. Further, the opposed part 233 is a part facing the third magnetic detection element 13. Therefore, the third magnetic detection element 13 is provided in a facing region between the opposed portion 233 and the first magnetic shield 21M.

Note that the bus bars 210 to 230 employed in the present modification are examples. The bus bars 210 to 230 are not limited to this.

Next, the first magnetic shield 21M and the second magnetic shield 22M will be described. The first magnetic shield 21M is the same as the configuration in which the thick part 2 of the first magnetic shield 21M is increased to three. On the other hand, the second magnetic shield 22M is the same as the configuration in which the thick part 2A of the second magnetic shield 22A is increased to three.

In the first magnetic shield 21M, as shown in FIG. 24, three thick portions 2 are arranged in the X direction, and each of the three thick portions 2 is opposed to each of the magnetic detection elements 11-13. Has been placed. The first magnetic shield 21 </ b> M protrudes from the surface layer portion 21 </ b> M <b> 1 including the thin portion 3, and the end layer portion provided continuously with the thin portion 3 in each thick portion 2, and the end layer portion in each thick portion 2. It has the protrusion part 21M2, and the recessed part 1 is formed between the protrusion parts 21M2. That is, it can be said that the surface layer portion 21M1 includes a part of the thick portion 2 and the thin portion 3. In this modification, the first magnetic shield 21M including the three protrusions 21M2 included in each of the three phases P1 to P3 and the two thin portions 3 is employed.

The end layer portion is a portion excluding the thin portion 3 in the surface layer portion 21M1, and is a portion facing the protruding portion 21M2 in the thick portion 2. The end layer portion can also be said to be a portion extending in the X direction with respect to the thin portion 3.

Here, as an example, the first magnetic shield 21M having a structure in which the surface layer portion 21M1 and the protruding portion 21M2 are laminated and integrated is adopted. Each of the surface layer portion 21M1 and the protruding portion 21M2 may be configured by laminating a plurality of layers made of a magnetic material. However, the first magnetic shield 21M is not limited to this, and the surface layer portion 21M1 and the protruding portion 21M2 may be integrally formed using a mold, or the surface layer portion 21M1 and the protruding portion 21M2 may be formed by cutting or the like. It may be formed integrally.

Similarly, the second magnetic shield 22M includes a thin layer portion 3A and a surface layer portion 22M1 including an end layer portion connected to the thin portion 3A in each thick portion 2A, and an end layer portion in each thick portion 2A. And a recess 1 is formed between the protrusions 22M2. The second magnetic shield 22M differs from the surface layer portion 21M1 of the first magnetic shield 21M in the thickness of the surface layer portion 22M1, and the other points are the same.

Further, the protruding portion 21M2 of the first magnetic shield 21M is disposed opposite to the protruding portion 22M2 of the second magnetic shield 22M. That is, in the current sensor 119, the projecting portion 21M2 of the first phase P1 and the projecting portion 22M2 are arranged to face each other, the projecting portion 21M2 of the second phase P2 and the projecting portion 22M2 are arranged to face each other, and the projecting portion of the third phase P3. 21M2 and the protrusion 22M2 are arranged to face each other. Each of the magnetic detection elements 11 to 13 is individually arranged in a facing region of the projecting portions 21M2 and 22M2 arranged to face each other.

In both the magnetic shields 21M and 22M, the thick portions 2 and 2A disposed to face the first magnetic detection element 11 can be said to be the thick portions 2 and 2A of the first phase P1. Therefore, the protruding portions 21M2 and 22M2 in the thick portions 2 and 2A can be said to be the protruding portions 21M2 and 22M2 of the first phase P1. Furthermore, it can be said that the end layer part which is the part which this protrusion part 21M2, 22M2 opposes is an end layer part of the 1st phase P1. The same applies to the thick portions 2 and 2A disposed opposite to the second magnetic detection element 12 and the thick portions 2 and 2A disposed opposite to the third magnetic detection element 13. Moreover, both magnetic shields 21M and 22M are formed of the thin portions 3 and 3A connecting the thick portions 2 and 2A of the first phase P1 and the thick portions 2 and 2A of the second phase P2, and the second phase P2. It can be said that the thick portions 2 and 2A and the thin portions 3 and 3A connecting the thick portions 2 and 2A of the third phase P3 are included.

Therefore, the first phase P1 is opposed to the first magnetic detection element 11, the thick portion 2 facing the first magnetic detection element 11 in the first magnetic shield 21M, and the first magnetic detection element 11 in the second magnetic shield 22M. It can be said that the thick part 2A to be included is included. That is, the first phase P1 includes the first magnetic detection element 11 that is disposed to face the first bus bar 210 and detects a magnetic field generated from the first bus bar 210 and converts it into an electric signal.

Similarly, the second phase P2 is opposed to the second magnetic detection element 12, the thick portion 2 facing the second magnetic detection element 12 in the first magnetic shield 21M, and the second magnetic detection element 12 in the second magnetic shield 22M. The thick part 2A to be included is included. That is, the second phase P <b> 2 includes the second magnetic detection element 12 that is disposed opposite to the second bus bar 220 and detects a magnetic field generated from the second bus bar 220 and converts it into an electric signal.

Further, the third phase P3 faces the third magnetic detection element 13, the thick portion 2 facing the third magnetic detection element 13 in the first magnetic shield 21M, and the third magnetic detection element 13 in the second magnetic shield 22M. The thick part 2A is included. That is, the third phase P3 includes the third magnetic detection element 13 that is disposed opposite to the third bus bar 230 and detects a magnetic field generated from the third bus bar 230 and converts it into an electric signal.

Note that the current sensor 119 is configured by, for example, integrally assembling each phase P1 to P3 via a circuit board or a housing. This circuit board is electrically connected to the magnetic detection elements 11 to 13, and sensor signals from the magnetic detection elements 11 to 13 are input. Further, the current sensor 119 may be configured by integrally assembling the bus bars 210 to 230 via the circuit board and the housing in addition to the phases P1 to P3. Thus, the structure in which the bus bars 210 to 230 and the like are integrally assembled can also be called a terminal block. Each of the phases P1 to P3 can also be regarded as including the corresponding bus bars 210, 220, and 230.

The three phases P1 to P3 thus configured are arranged side by side in the X direction as shown in FIGS. 23 and 24, and the thick portions 2 and 2A are connected via the thin portions 3 and 3A. . In addition, it can be said that the phases P1 to P3 are arranged so that the current flowing direction (Y direction) is parallel in the opposed portions 213, 223, and 233. In the following, adjacent phases are also referred to as adjacent phases. The direction in which the three phases P1 to P3 are arranged can be said to be the arrangement direction.

In this embodiment, an example in which the first phase P1, the second phase P2, and the third phase P3 are arranged in the order in the X direction is employed. Therefore, the second phase P2 can be said to be an intermediate phase sandwiched between the first phase P1 and the third phase P3. The second phase P2 is adjacent to the first phase P1 and is adjacent to the third phase P3. That is, the first phase P1 and the third phase P3 are not adjacent to each other.

For this reason, the magnetic detection elements 11 to 13 are arranged side by side in the X direction. Further, the first magnetic shield 20 has the thick portions 2 arranged in the X direction. Similarly, in the second magnetic shield 22M, the thick portions 2A are arranged in the X direction. The opposed portions 213, 223, and 233 corresponding to the phases P1 to P3 are also arranged in the X direction.

The current sensor 119 configured in this manner detects a detected current flowing in a bus bar that is a detection target in a phase adjacent to this phase when a relatively large current such as 1200 A flows in the bus bar that is a detection target in a certain phase. Situation. A bus bar in which a relatively large current flows can be a noise generation source. For this reason, the phase for which this bus bar is the detection target can be said to be a noise phase. On the other hand, the phase for detecting the detected current can be said to be a detection phase. In this modification, as shown in FIG. 24, the situation where the third phase P3 is a noise phase and the second phase P2 is a detection phase is adopted as an example.

The magnetic field generated from the third bus bar 230 in the noise phase is generated concentrically according to the right-hand rule of amperes. This magnetic field is concentrated inside the first magnetic shield 21M and the second magnetic shield 22M. Then, as shown in FIG. 24, magnetic flux flows through the first magnetic shield 21M and the second magnetic shield 22M in the direction indicated by the solid line arrow, in other words, lines of magnetic force run.

In particular, the current sensor 119 controls the magnetic flow path by providing the concave portions 1 in both the magnetic shields 21M and 22M as described in the above-described embodiments and modifications, so that the lines of magnetic force of the magnetic shields 21M and 22M. It runs on the outer surface. For this reason, as for the current sensor 119, a magnetic force line runs through both surface layer parts 21M1 and 22M1. The magnetic field lines in the first magnetic shield 21M and the magnetic field lines in the second magnetic shield 22M are inverse vectors.

For this reason, the current sensor 119 can reduce the leakage magnetic field more than the current sensor of the comparative example. However, in the current sensor 119, as shown in FIG. 24, a leakage magnetic field may be generated from the recess 1 due to the size of both surface layer portions 21M1 and 22M1, the magnetic flux flowing through both surface layer portions 21M1 and 22M1, or the like. In the present embodiment, as shown in FIG. 24, an example is adopted in which a leakage magnetic field as typified by an alternate long and short dash line LM1 or LM2 is generated from the recess 1 of both magnetic shields 21M and 22M.

When the leakage magnetic fields LM1 and LM2 are directed to the second magnetic detection element 12 of the second phase P2 and pass through the second magnetic detection element 12, there is a possibility that the magnetoelectric conversion result by the second magnetic detection element 12 is affected. . That is, when the magnetic field formed from the recesses 1 and 1A reaches the second magnetic detection element 12, the current sensor 119 may affect the magnetoelectric conversion result by the second magnetic detection element 12. The second magnetic detection element 12 corresponds to a magnetic detection element sandwiched between two magnetic detection elements 11 and 13.

The vectors of the leakage magnetic fields LM1 and LM2 are inverse vectors at the position of the second magnetic detection element 12. Therefore, the current sensor 119 cancels out the leakage magnetic field LM1 and the leakage magnetic field LM2, and prevents both the leakage magnetic fields LM1 and LM2 from reaching the second magnetic detection element 12 in the intermediate phase and the second magnetic shield 21M. At least one shape of the shield 22M is adjusted. That is, in the current sensor 119, the shape of at least one of the first magnetic shield 21M and the second magnetic shield 22M is adjusted so that the leakage magnetic fields LM1 and LM2 are canceled at the position of the second magnetic detection element 12. It can be said. For this reason, both magnetic shields 21M and 22M have shapes adjusted so as to cancel each other with both leakage magnetic fields LM1 and LM2 so that both leakage magnetic fields LM1 and LM2 do not reach the second magnetic detection element 12. It can also be said.

In this modification, an example is adopted in which the thicknesses of the surface layer portions 21M1 and 22M1 are adjusted with respect to the total thickness of the magnetic shields 21M and 22M. For example, in the case of the first magnetic shield 21M, the total thickness is a thickness obtained by adding the thickness of the surface layer portion 21M1 and the thickness of the protruding portion 21M2. Here, the thickness is a length in the stacking direction.

Further, in this modification, the overall thickness t1 of the first magnetic shield 21M and the overall thickness t1 of the second magnetic shield 22M are the same. In this modification, as shown in FIGS. 25 and 26, the thickness t3 of the surface layer portion 21M1 of the first magnetic shield 21M is adjusted to be larger than the thickness t2 of the surface layer portion 22M1 of the second magnetic shield 22M. The example that is being adopted is adopted. FIG. 25 is an enlarged view of a part of the first magnetic shield 21M in FIG.

Therefore, in the first magnetic shield 21M, the thickness (t1-t3) of the protruding portion 21M2 is thinner than the thickness (t1-t2) of the protruding portion 22M2 of the second magnetic shield 22M. FIG. 26 is a cross-sectional view when the surface layer portion 21M1 of the first magnetic shield 21M has the same thickness as the surface layer portion 22M1 of the second magnetic shield 22M. Therefore, the second magnetic shield 22M can be regarded as the same shape and size as the first magnetic shield 21M shown in FIG.

However, the present disclosure is not limited to this. In the present disclosure, at least one of the thickness of the surface layer portion 21M1 with respect to the entire thickness of the first magnetic shield 21M and the thickness of the surface layer portion 22M1 with respect to the entire thickness of the second magnetic shield 22M is determined according to the state of the leakage magnetic fields LM1 and LM2. Should be adjusted.

In each of the surface layer portions 21M1 and 22M1, the amount of the leakage magnetic field decreases as the thickness increases, and the amount of the leakage magnetic field increases as the thickness decreases. That is, the current sensor 119 controls the amount of the leakage magnetic field by adjusting the thickness of at least one of the surface layer portions 21M1 and 22M1, and the leakage magnetic field LM1 and the leakage magnetic field LM2 cancel each other at the position of the second magnetic detection element 12. It is configured to be. Therefore, in the present embodiment, the amount of the leakage magnetic field LM1 from the recess 1 of the first magnetic shield 21M is reduced, and both the leakage magnetic fields LM1 and LM2 are canceled at the position of the second magnetic detection element 12. Yes.

The current sensor 119 controls the amount of the leakage magnetic field by adjusting at least one of the thickness of the surface layer portion 21M1 and the thickness of the surface layer portion 22M1, and the leakage magnetic field LM1 and the leakage magnetic field LM2 are transferred to the second magnetic detection element 12. It can be said that the influence is suppressed. Furthermore, it can be said that the current sensor 119 is configured such that the leakage magnetic field LM1 and the leakage magnetic field LM2 are weakened at the position of the second magnetic detection element 12.

By the way, the thickness of the surface layer portion 21M1 with respect to the entire thickness of the first magnetic shield 21M is the number of magnetic material layers constituting the surface layer portion 21M1 and the number of magnetic material layers constituting the protruding portion 21M2. Can be adjusted by number. The same applies to the adjustment of the thickness of the surface layer portion 22M1 with respect to the entire thickness of the second magnetic shield 22M.

Further, the thickness of the surface layer portion 21M1 and the thickness of the surface layer portion 22M1 can be set to values such that both the leakage magnetic fields LM1 and LM2 are canceled at the position of the second magnetic detection element 12 by simulation or experiment.

As described above, in the current sensor 119, the thickness of at least one of the surface layer portions 21M1 and 22M1 is adjusted so that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at the position of the second magnetic detection element 12. For this reason, even when the leakage magnetic fields LM1 and LM2 are generated from the recesses 1 of the magnetic shields 21M and 22M toward the second magnetic detection element 12, the current sensor 119 uses the leakage magnetic fields LM1 and LM2 for the second time. It can suppress that the magnetic detection element 12 senses. Therefore, the current sensor 119 can detect the current with high accuracy. Naturally, the current sensor 119 can achieve the same effects as the current sensors 100 and 101.

Furthermore, the magnetic detection element of the detection phase may affect the magnetoelectric conversion result even if the magnetic field generated from the noise phase bus bar is sensed. For example, when the first phase P1 is a noise phase and the second phase P2 is a detection phase, the second magnetic detection element 12 is affected by the magnetic field emitted from the extension 215, the second extension 216, etc. of the first bus bar 210. There is a possibility of receiving. Therefore, in the current sensor 119, the thickness of the first surface layer portions 21M1 and 22M1 is set so that not only the leakage magnetic fields LM1 and LM2 but also the magnetic field generated from the first bus bar 210 does not reach the second magnetic detection element 12. And preferred.

Note that the modified example 19 can be implemented in combination with each of the modified examples 10 to 12. Even in this case, the same effect as the current sensor 119 can be obtained. Further, the current sensor 119 can employ two magnetic shields 21M and 22M having the same shape as the first magnetic shield 21B of the second modification and the first magnetic shield 21C of the third modification. When the first magnetic shield 21B is employed, the current sensor 119 has a configuration in which the thickness of the thin portion 3B is adjusted. On the other hand, the current sensor 119 has a configuration in which the thickness of the lid portion 3C is adjusted when the first magnetic shield 21C of Modification 3 is employed. These points are the same in the following modified examples.

(Modification 20)
A current sensor of Modification 20 will be described with reference to FIG. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. FIG. 27 shows only the first magnetic shield 21M as an example. FIG. 27 is a cross-sectional view corresponding to FIG.

The current sensor of Modification 20 is different from the current sensor 119 in that the gap g1 between the protrusions is adjusted. That is, in the current sensor, the gap g1 in at least one of the two magnetic shields 21M and 22M is adjusted so that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at the position of the second magnetic detection element 12, for example. In other words, at least one of the two magnetic shields 21 </ b> M and 22 </ b> M has a shape in which a gap g <b> 1 between adjacent protrusions is adjusted via the recess 1.

The gap g1 is, for example, the distance in the X direction between the protruding portion 21M2 of the first phase P1 and the protruding portion 21M2 of the second phase P2 in the first magnetic shield 21M. In addition, the space | gap g1 here can also be said to be the width | variety of the recessed part 1 in a X direction.

In each of the magnetic shields 21M and 22M, the amount of the leakage magnetic field decreases as the interval g1 decreases, and the amount of the leakage magnetic field increases as the interval g1 increases. Therefore, the current sensor controls the amount of the leakage magnetic field by adjusting the distance g1 between at least one of the two magnetic shields 21M and 22M, and the leakage magnetic field LM1 and the leakage magnetic field LM2 are the positions of the magnetic detection elements in the detection phase. It is configured to be canceled by. For example, the current sensor is configured such that the gap g1 in the first magnetic shield 21M is narrower than the gap g1 in the second magnetic shield 22M.

Modification 20 can provide the same effects as Modification 19. In addition, the present disclosure can be implemented by combining the technique disclosed in the modification 20 and the technique disclosed in the modification 19. Even in this case, the same effects as those of Modification 20 can be obtained.

(Modification 21)
A current sensor of Modification 21 will be described with reference to FIG. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. In FIG. 28, only the first magnetic shield 21M is illustrated as an example. FIG. 28 is a cross-sectional view corresponding to FIG.

The current sensor of Modification 21 is different from the current sensor 119 in that the length t12 of the thin portions 3 and 3A is adjusted. That is, in the current sensor, the length of the thin portions 3 and 3A in at least one of the two magnetic shields 21M and 22M is set such that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at the position of the second magnetic detection element 12, for example. t12 is adjusted. In other words, at least one of the two magnetic shields 21M and 22M has a shape in which the length t12 of the thin portions 3 and 3A at the facing portion is adjusted.

The length t12 is the length of the thin portion 3 in the Y direction. The length t12 can also be said to be the length of the thin portion 3 in the direction orthogonal to the stacking direction and the arrangement direction. The length t11 of the thick portion 2 described later is the length in the Y direction, similarly to t12.

In the first magnetic shield 21M, as shown in FIG. 28, the thick portions 2 adjacent to each other through the thin portions 3 are connected to each other through only the thin portions 3 through a part of the opposing portions. For example, the thick part 2 of the first phase P1 and the thick part 2 of the second phase P2 are connected via the thin part 3 only in a part in the Z direction and the Y direction at the mutually facing portions. Yes. For this reason, the length t11 of the thick part 2 is longer than the length t12 of the thin part 3. Therefore, the first magnetic shield 21M has a recess formed between the adjacent thick portions 2 in the XY plane.

As in the case of the first magnetic shield 21M, the second magnetic shield 22M is connected to the thick portions 2A adjacent to each other through the thin portions 3A, and only a part of the opposing portions are connected via the thin portions 3A. ing. However, the current sensor may have a configuration in which at least one of the two magnetic shields 21M and 22M is partially connected as described above. Therefore, for example, one of the two magnetic shields 21M and 22M may have a configuration in which the whole in the Y direction is connected as employed in the modification 19.

In each of the magnetic shields 21M and 22M, the amount of the leakage magnetic field decreases as the length t12 increases, and the amount of the leakage magnetic field increases as the length t12 decreases. Therefore, the current sensor controls the amount of the leakage magnetic field by adjusting the length t12 of at least one of the two magnetic shields 21M and 22M, and the leakage magnetic field LM1 and the leakage magnetic field LM2 are the detection phase magnetic detection elements. It is configured to be canceled at the position. For example, the current sensor is configured such that the length t12 in the first magnetic shield 21M is shorter than the length t12 in the second magnetic shield 22M.

Modification 21 can achieve the same effects as Modification 19. Moreover, this indication can also be implemented combining the technique disclosed by the modification 21 and the technique disclosed by the modifications 19 and 20. FIG. Even in this case, the same effect as that of the modified example 21 can be obtained.

(Modification 22)
With reference to FIG. 29, the current sensor of Modification 22 will be described. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. FIG. 29 shows only the first magnetic shield 21M as an example. FIG. 29 is a cross-sectional view corresponding to FIG.

The current sensor of Modification 22 employs the same shape as that of the first magnetic shield 21D of Modification 4 for at least one of the two magnetic shields 21M and 22M. The current sensor of Modification 22 is different from the current sensor 119 in that the depth t4 of the recesses 1 and 1A is adjusted. That is, the current sensor has a depth t4 of the recesses 1 and 1A in at least one of the two magnetic shields 21M and 22M so that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at, for example, the position of the second magnetic detection element 12. Has been adjusted. In other words, at least one of the two magnetic shields 21M and 22M is adjusted in the depth t4 of the recesses 1 and 1A. The depth t4 is the length in the Z direction.

In the current sensor, it is sufficient that at least one of the two magnetic shields 21M and 22M has the configuration shown in FIG. Therefore, for example, one of the two magnetic shields 21 </ b> M and 22 </ b> M may have the configuration employed in the modification 19.

In each of the magnetic shields 21M and 22M, the amount of the leakage magnetic field decreases as the depth t4 increases, and the amount of the leakage magnetic field increases as the depth t4 decreases. Therefore, the current sensor controls the amount of the leakage magnetic field by adjusting the depth t4 of at least one of the two magnetic shields 21M and 22M, and the leakage magnetic field LM1 and the leakage magnetic field LM2 are the detection phase magnetic detection elements. It is configured to be canceled at the position. For example, the current sensor is configured such that the depth t4 in the first magnetic shield 21M is shorter than the depth t4 in the second magnetic shield 22M.

Modification 22 can provide the same effects as Modification 19. In addition, the present disclosure can be implemented by combining the technique disclosed in the modification 22 and each of the techniques disclosed in the modifications 19 to 21. Even in this case, the same effects as those of the modification 22 can be obtained. Furthermore, the modified example 22 can achieve the same effects as the modified example 4.

(Modification 23)
With reference to FIG. 30, the current sensor of Modification Example 23 will be described. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. FIG. 30 illustrates only the first magnetic shield 21M as an example. FIG. 30 is a cross-sectional view corresponding to FIG.

The current sensor of Modification Example 23 employs the same shape as that of the first magnetic shield 21E of Modification Example 5 for at least one of the two magnetic shields 21M and 22M. The current sensor of Modification 23 is different from the current sensor 119 in that the inclination angle θ of the inclined portion 1M corresponding to the inclined portion 1E of the first magnetic shield 21E is adjusted. That is, in the current sensor, the inclination angle θ in at least one of the two magnetic shields 21M and 22M is adjusted so that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at the position of the second magnetic detection element 12, for example. . In other words, at least one of the two magnetic shields 21M and 22M has the inclination angle θ adjusted as a shape. In addition, this inclination | tilt angle (theta) is corresponded to the angle which the bottom face and side surface (inclination part 1M) of the recessed part 1 in an XZ plane make.

In the current sensor, at least one of the two magnetic shields 21M and 22M may be configured as shown in FIG. Therefore, for example, one of the two magnetic shields 21 </ b> M and 22 </ b> M may have the configuration employed in the modification 19.

In each of the magnetic shields 21M and 22M, the amount of the leakage magnetic field decreases as the inclination angle θ decreases, and the amount of the leakage magnetic field increases as the inclination angle θ increases. Therefore, the current sensor controls the amount of the leakage magnetic field by adjusting the inclination angle θ of at least one of the two magnetic shields 21M and 22M, and the leakage magnetic field LM1 and the leakage magnetic field LM2 are the detection phase magnetic detection elements. It is configured to be canceled at the position. For example, the current sensor is configured such that the inclination angle θ in the first magnetic shield 21M is smaller than the inclination angle θ in the second magnetic shield 22M.

Modification 23 can achieve the same effects as Modification 19. In addition, the present disclosure can be implemented by combining the technology disclosed in the modified example 23 and each of the technologies disclosed in the modified examples 19 to 22. Even in this case, the same effect as that of the modified example 23 can be obtained. Furthermore, the modified example 23 can achieve the same effects as the modified example 5.

In addition, the current sensor of Modification Example 23 can adopt the same shape as the first magnetic shield 21F of Modification Example 6 for at least one of the two magnetic shields 21M and 22M. Even in this case, the same effect can be obtained. Furthermore, in this case, the current sensor can adjust the amount of the leakage magnetic field not only by the inclination angle θ but also by the depth of the recess 1.

(Modification 24)
With reference to FIG. 31, the current sensor of Modification Example 24 will be described. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. FIG. 31 shows only the first magnetic shield 21M as an example. FIG. 31 is a cross-sectional view corresponding to FIG.

The current sensor of Modification 24 employs a shape in which the protrusion 8 is formed on at least one of the two magnetic shields 21M and 22M. For example, as shown in FIG. 31, the first magnetic shield 21 </ b> M has protrusions 8 formed at positions along the concave portion 1 in the thick portion 2. The current sensor of Modification 24 is different from the current sensor 119 in that the length of the protrusion 8 is adjusted. That is, in the current sensor, the length of the protrusion 8 on at least one of the two magnetic shields 21M and 22M is adjusted so that the leakage magnetic field LM1 and the leakage magnetic field LM2 are canceled at the position of the second magnetic detection element 12, for example. ing. In other words, at least one of the two magnetic shields 21M and 22M is shaped so that the length of the protrusion 8 is adjusted. This length is the length in the Z direction.

In the current sensor, at least one of the two magnetic shields 21M and 22M may be configured as shown in FIG. Therefore, for example, one of the two magnetic shields 21 </ b> M and 22 </ b> M may have the configuration employed in the modification 19.

In each of the magnetic shields 21M and 22M, the amount of the leakage magnetic field decreases as the length of the protrusion 8 increases, and the amount of the leakage magnetic field increases as the length of the protrusion 8 decreases. Therefore, the current sensor controls the amount of the leakage magnetic field by adjusting the length of at least one protrusion 8 of the two magnetic shields 21M and 22M, and the leakage magnetic field LM1 and the leakage magnetic field LM2 detect the magnetic phase. It is configured to cancel at the position of the element. For example, the current sensor is configured such that the length of the protrusion 8 on the first magnetic shield 21M is shorter than the length of the protrusion 8 on the second magnetic shield 22M.

Modification 24 can achieve the same effects as Modification 19. In addition, the present disclosure can be implemented by combining the technology disclosed in the modified example 24 and each of the technologies disclosed in the modified examples 19 to 23. Even in this case, the same effect as that of the modified example 24 can be obtained. In the modified example 24, the amount of the leakage magnetic field can be adjusted by adjusting the length of at least one of the two protrusions 8 along the recess 1.

(Modification 25)
The current sensor 120 according to the modified example 25 will be described with reference to FIGS. In the present modification, for convenience, the same reference numerals as those in the modification 19 are used for some of the reference numerals. The current sensor 120 is different from the current sensor 119 in the number of phases and the configuration of the two magnetic shields 21N and 22N. Further, the current sensor 120 can be regarded as an example of a configuration in which the techniques of the modified examples 19 to 21 are combined.

32, 33, and 34, the current sensor 120 has a fourth phase P4 corresponding to the fourth bus bar 240 in addition to the first phase P1 to the third phase P3. The fourth phase P3 includes the fourth magnetic detection element 14 and the thick portions 2 and 2A, like the other phases P1 to P3. The fourth magnetic detection element 14 is disposed opposite to the fourth bus bar 240 and has the same configuration as the other magnetic detection elements 11 to 13.

The first magnetic shield 21N includes a surface layer portion 21N1 and a protruding portion 21N2. As for the 1st magnetic shield 21N, the thickness of the surface layer part 21N1 is adjusted like the modification 19. That is, in the first magnetic shield 21N, as shown in FIG. 33, the thickness of the surface layer portion 21N1 of the first phase P1 and the second phase P2 is the same, and the thickness of the surface layer portion 21N1 of the third phase P3 and the fourth phase P4. And the thicknesses of the surface layer portions 21N1 of the first phase P1 and the third phase P3 are adjusted to be different.

Further, the interval of the first magnetic shield 21N is adjusted as in Modification 20. That is, as shown in FIGS. 32 and 33, the first magnetic shield 21N includes an interval g4 between the first phase P1 and the second phase P2, an interval g5 between the second phase P2 and the third phase P3, and a third phase. The gap g6 between P3 and the fourth phase P4 is adjusted to be different. These intervals are g5 <g4 <g6.

Furthermore, the length of the thin portion 3 of the first magnetic shield 21N is adjusted as in the modified example 21. That is, in the first magnetic shield 21N, as shown in FIG. 32, the length of the thin portion 3 between the third phase P3 and the fourth phase P4 is adjusted to be shorter than the lengths of the other thin portions 3. .

On the other hand, the second magnetic shield 22N includes a surface layer portion 22N1 and a protruding portion 22N2. As for the 2nd magnetic shield 22N, the thickness of surface layer part 22N1 is adjusted like the modification 19. That is, in the second magnetic shield 22N, as shown in FIG. 33, the thickness of the surface layer portion 22N1 of the second phase P2 and the third phase P3 is the same, and the thickness of the surface layer portion 22N1 of the first phase P1 and the fourth phase P4. And the thicknesses of the surface layer portions 22N1 of the first phase P1 and the second phase P2 are adjusted to be different.

Further, the interval of the second magnetic shield 22N is adjusted as in Modification 20. That is, as shown in FIGS. 33 and 34, the second magnetic shield 22N includes an interval g7 between the first phase P1 and the second phase P2, an interval g8 between the second phase P2 and the third phase P3, and a third phase. The gap g9 between P3 and the fourth phase P4 is adjusted to be different. These intervals are g8 <g7 = g9.

And as for the 2nd magnetic shield 22N like the modification 21, the length of the thin part 3 is adjusted. That is, in the second magnetic shield 22N, as shown in FIG. 34, the length of the thin portion 3 between the first phase P1 and the second phase P2 is adjusted to be shorter than the length of the other thin portions 3. .

The shape of the current sensor 120 thus configured is adjusted so that the leakage magnetic fields LM1 and LM2 from the recesses 1 and 1A do not reach the detection phase magnetic detection element. Therefore, the modified example 25 can achieve the same effects as the modified example 19.

(Modification 26)
The current sensor 121 according to the modified example 26 will be described with reference to FIG. In addition, in this modification, the same code | symbol as the modification 19 is employ | adopted for convenience. FIG. 35 is a cross-sectional view corresponding to FIG. However, FIG. 35 illustrates only the opposed portions 213 and 223 for the first bus bar 210 and the second bus bar 220 in order to simplify the drawing.

The current sensor 121 is different from the current sensor 119 in that the number of phases is two. That is, the current sensor 121 has the first phase P1 and the second phase P2, but does not have the third phase P3.

Even in such a current sensor 121, one phase may be a noise phase and the other phase may be a detection phase. In the present modification, as shown in FIG. 35, a situation where the second phase P2 is a noise phase and the first phase P1 is a detection phase is adopted as an example. In this case, when the magnetic field formed from the recesses 1, 1 </ b> A reaches the first magnetic detection element 11, the current sensor 121 may affect the magnetoelectric conversion result by the first magnetic detection element 11.

Therefore, as in the modification 19, the current sensor 121 is adjusted in shape so that at least one of the thicknesses of the surface layer portions 21M1 and 22M1 with respect to the total thickness of the magnetic shields 21M and 22M is adjusted. For this reason, both magnetic shields 21M and 22M have shapes adjusted so as to cancel each other with both leakage magnetic fields LM1 and LM2 so that both leakage magnetic fields LM1 and LM2 do not reach the first magnetic detection element 11. It can also be said.

Modification 26 can achieve the same effects as Modification 19. In addition, the present disclosure can be implemented by combining the technology disclosed in the modified example 26 and each of the technologies disclosed in the modified examples 19 to 25. Even in this case, the same effect as that of the modified example 26 can be obtained. Further, the current sensor 121 of the modified example 26 can achieve the same effect even when the first phase P1 and the second phase P2 are two phases of three or more phases.

(Second Embodiment)
The current sensor 400 according to the second embodiment will be described with reference to FIGS. The current sensor 400 is mounted on a vehicle together with, for example, an inverter that converts DC power into three-phase AC power and a motor generator that is driven by the three-phase AC power from the inverter. Current sensor 400 detects a current flowing between the inverter and the motor generator. More specifically, current sensor 400 individually detects the current flowing through each of a plurality of bus bars 340 electrically connecting the inverter and the motor generator. As the current sensor 400, for example, a coreless current sensor that does not require a magnetic collecting core can be adopted. Current sensor 400 is not limited to one that detects a current flowing between the inverter and the motor generator.

As will be described later, the current sensor 400 includes a plurality of phases P1 to Pn. At least three of the phases P1 to Pn are provided corresponding to the phases between the inverter and the motor generator. Bus bar 340 corresponds to a current path. It can be said that the current flowing through the bus bar 340 is a detected current.

In the present embodiment, as an example, a bus bar 340 including a first end portion, a second end portion, and an intermediate portion 340a sandwiched between both end portions is employed. In the bus bar 340, for example, the first end is an end on the motor generator side, and the second end is an end on the inverter side. The intermediate part 340a is a part between the first end part and the second end part, and is a part sandwiched between a first shield and a second shield described later. However, the configuration of the bus bar 340 is not limited to this.

The current sensor 400 includes a first phase P1 to an n-th phase Pn as shown in FIGS. In the current sensor 400, the first phase P1 to the n-th phase Pn are arranged in the X direction. Therefore, it can be said that the X direction is also an arrangement direction. Furthermore, the arrangement direction is a direction orthogonal to the stacking direction described later.

Moreover, since the first phase P1 and the nth phase are phases at both ends in the arrangement direction, they can be said to be end phases. On the other hand, the second phase P2 to the (n-1) th phase Pn-1 are intervening phases because they are interposed between the end phases P1 and Pn. In the present embodiment, an example in which n is a natural number of 3 or more is employed. However, the present disclosure can be adopted if n is 2 or more. The current sensor in this case does not have an intervening phase which will be described later.

Each phase P1 to Pn includes magnetic detection elements 310 and 311. Further, each of the phases P1 to Pn includes a magnetic shield portion including a pair of first shields 321 and 322 and second shields 331 and 332 that are arranged to face each other while sandwiching the bus bar 340 and the magnetic detection elements 310 and 311. .

Each of the magnetic detection elements 310 and 311 is disposed opposite to one bus bar 340, detects a magnetic field generated from the bus bar 340, and converts it into an electric signal. In the magnetic detection elements 310 and 311, for example, a sensor chip, a bias magnet, and a circuit chip are mounted on a substrate, and these are sealed with a sealing resin body, and leads connected to the circuit chip are outside the sealing resin body. An exposed configuration can be adopted. As the sensor chip, for example, a giant magnetoresistive element (GMR), an anisotropic magnetoresistive element (AMR), a tunnel magnetoresistive element (TMR), or a Hall element can be adopted. The magnetic detection elements 311 of the end phases P1 and Pn can be said to be end phase detection elements 311. On the other hand, the magnetic detecting elements 310 of the intervening phases P2 to Pn-1 can be said to be intervening detecting elements 310.

The first shields 321 and 322 and the second shields 331 and 332 are made of a magnetic material, and shield the magnetic field from the outside with respect to the magnetic detection elements 310 and 311. The shields 321, 322, 331, and 332 are arranged to face each other while sandwiching the bus bar 340 and the magnetic detection elements 310 and 311. In other words, the shields 321, 322, 331, and 332 are for suppressing the external magnetic field from reaching or passing through the magnetic detection elements 310 and 311. The first shields 321 and 322 and the second shields 331 and 332 correspond to magnetic shield portions.

Each shield 321, 322, 331, 332 is configured by laminating flat magnetic materials, for example. Therefore, as shown in FIGS. 36 and 37, each of the shields 321, 322, 331, and 332 is a flat plate member, and has, for example, a rectangular shape in the XY plane, the YZ plane, and the XZ plane. Further, the shields 321, 322, 331, and 332 are large enough to cover the opposing areas of the magnetic detection elements 310 and 311 and the opposing area of the intermediate portion 340a. The facing area is an area in the Z direction.

The first shield 322 of the end phases P1 and Pn can be said to be the first end phase shield 322. Similarly, the second shield 332 of the end phases P1 and Pn can be said to be the second end phase shield 332. Therefore, the current sensor 400 includes two first end phase shields 322 and two second end phase shields 332.

On the other hand, the first shield 321 of the intervening phases P2 to Pn-1 can be said to be the first intervening shield 321. Similarly, the second shield 331 of the intervening phases P2 to Pn-1 can be said to be the second intervening shield 331.

Thus, the first shield includes the first intervening shield 321 and the first end-phase shield 322. The second shield includes a second intervening shield 331 and a second end phase shield 332.

The first shields 321 and 322 are arranged on one side in the Z direction with reference to the bus bar 340 and the magnetic detection elements 310 and 311. The second shields 331 and 332 are arranged on the other side in the Z direction with respect to the bus bar 340 and the magnetic detection elements 310 and 311. Specifically, the first shields 321 and 322 are disposed on the side facing the bus bar 340, and the second shields 331 and 332 are disposed on the side facing the magnetic detection elements 310 and 311.

Each of the first shields 321 and 322 and each of the second shields 331 and 332 make a pair, and are arranged to face each other with an interval in the Z direction. For example, in the first phase P1, the first end-phase shield 322 and the second end-phase shield 332 make a pair, and the first end-phase shield 322 and the second end-phase shield 332 are arranged to face each other in the Z direction. Has been. The first end-phase shield 322 and the second end-phase shield 332 are arranged so as to sandwich the end-phase detection element 311 and the bus bar 340 in the Z direction.

Therefore, it can be said that the end phase detection element 311 and the intermediate portion 340 a are disposed in the opposing region of the first end phase shield 322 and in the opposing region of the second end phase shield 332. In the first phase P1, as shown in FIG. 37, the first end phase shield 322, the intermediate portion 340a of the bus bar 340, the end phase detection element 311 and the second end phase shield 332 are stacked in this order. That is, in the first phase P1, these components are stacked in the Z direction.

Further, for example, in the second phase P2, the first interposed shield 321 and the second interposed shield 331 form a pair, and the first interposed shield 321 and the second interposed shield 331 are arranged to face each other in the Z direction. Yes. The first interposed shield 321 and the second interposed shield 331 are arranged so as to sandwich the interposed detection element 310 and the bus bar 340 in the Z direction.

Therefore, it can be said that the interposition detection element 310 and the intermediate portion 340a are disposed in the opposing region of the first intervening shield 321 and in the opposing region of the second intervening shield 331. In the second phase P2, as shown in FIG. 37, the first interposed shield 321, the intermediate portion 340a of the bus bar 340, the interposed detecting element 310, and the second interposed shield 331 are stacked in this order. That is, in the second phase P2, these components are laminated in the Z direction.

As described above, the current sensor 400 has a configuration in which the first shields 321 and 322 are divided for each of the phases P1 to Pn and the second shields 331 and 332 are divided for each of the phases P1 to Pn. However, each of the first shields 321 and 322 and the second shields 331 and 332 may be integrated by a material that does not have a function as a magnetic shield such as resin.

The first shields 321 and 322 are arranged side by side in the X direction. Similarly, the second shields 331 and 332 are arranged side by side in the X direction. Note that the intermediate portion 340a of the bus bar 340 corresponding to each phase P1 to Pn is also arranged in the X direction.

In the first shields 321 and 322, for example, an opposing surface (hereinafter referred to as a first opposing surface) facing the intermediate portion 340a is provided in parallel with the XY plane. As for the 1st shield 321,322, the 1st opposing surface is provided on the same virtual plane parallel to XY plane. Similarly, in the second shields 331 and 332, for example, opposing surfaces (hereinafter referred to as second opposing surfaces) facing the magnetic detection elements 310 and 311 are provided in parallel with the XY plane. The second opposing surfaces of the second shields 331 and 332 are provided on the same virtual plane parallel to the XY plane. And the virtual plane in which the 1st opposing surface is provided differs in the position in a Z direction from the virtual plane in which the 2nd opposing surface is provided.

Note that the first facing surface is a surface facing the second shields 331 and 332. On the other hand, the second facing surface is a surface on the side facing the first shields 321 and 322. Moreover, since the 1st shield 321,322 and the 2nd shield 331,332 are arrange | positioned in parallel, it can also be said to be a parallel plate shield.

Further, the first shields 321 and 322 have different positions in the X direction, but have the same positions in the Y direction and the Z direction. Similarly, the second shields 331 and 332 have different positions in the X direction, but have the same positions in the Y direction and the Z direction.

In the current sensor 400 configured in this way, a relatively large current such as 1200A flows through the bus bar 340 that is a detection target of a certain phase, and the detected current that flows through the bus bar 340 that is the detection target in the adjacent phase of this phase. Can be detected. Note that the bus bar 340 in which a relatively large current flows can be a source of noise. For this reason, the phase for which this bus bar is the detection target can be said to be a noise phase. On the other hand, the phase for detecting the detected current can be said to be a detection phase. In the present modification, as shown in FIG. 37, a situation where the second phase P2 is a noise phase and the first phase P1 is a detection phase is adopted as an example.

The magnetic field generated from the noise phase bus bar 340 is generated concentrically by the right-handed screw law of amperes. This magnetic field is concentrated inside the shields 321, 322, 331, and 332. Then, as shown in FIG. 37, a magnetic flux flows in each shield 321, 322, 331, 332 in the direction indicated by the solid line arrow, in other words, a line of magnetic force runs.

And the magnetic field reaches the extreme end of the end phase. As a result, in the current sensor 400, magnetic field exchange occurs between the first shield and the second shield in the end phase. Specifically, in the first phase P <b> 1, magnetic field exchange from the outermost end portion of the second end phase shield 332 to the first end phase shield 322 occurs. Similarly, in the n-th phase Pn, magnetic field exchange from the outermost end portion of the first end-phase shield 322 to the second end-phase shield 332 occurs. In other words, in the first phase P <b> 1, the leakage magnetic field from the endmost part of the second end-phase shield 332 is transmitted to the endmost part of the first end-phase shield 322. Similarly, in the n-th phase Pn, the leakage magnetic field from the endmost portion of the first end-phase shield 322 is transmitted to the endmost portion of the second end-phase shield 332. In the current sensor 400, if the end phase detection element 311 senses this leakage magnetic field, a current detection error occurs.

In addition, depending on the direction of the current flowing through the bus bar 340, the direction may be opposite to the example adopted here. Here, the endmost portion is an end portion in the X direction, and is an end portion of the end phase shields 322 and 332 on the side not facing the intervening shields 321 and 331.

Therefore, the current sensor 400 is provided with a first end-phase shield 322 and a second end-phase shield 332 in order to suppress the occurrence of a current detection error. Here, the first end phase shield 322 and the second end phase shield 332 will be described. The first end phase shield 322 and the second end phase shield 332 have the same configuration. However, the end phase shields 322 and 332 are different in configuration from the intervening shields 321 and 331. Specifically, the end- phase shields 322 and 332 are different in positional relationship and size with the magnetic detection element 311 from the positional relationship between the intervening shields 321 and 331 and the intervening detection element 310 and the size of the intervening shields 321 and 331. .

The first end shield 322 includes a first base 322a and a first extension 322b. Similarly, the second end phase shield 332 includes a second base portion 332a and a second extension portion 332b. Both the extension portions 322b and 332b make it easier for the leakage magnetic field from the endmost portion of the end phase shields 322 and 332 to reach the opposite end phase shields 322 and 332 arranged opposite to each other than the end phase detection element 311. In addition, this is a part for exchanging magnetic fields between the two- phase shields 322 and 332. In the present embodiment, a magnetic field is transmitted from the second extension 332b of the first phase P1 to the first extension 322b of the first phase P1, and the first extension 322b of the n-phase Pn 2 The magnetic field is transmitted to the extension 332b. Both extension parts 322b and 332b correspond to a magnetic field exchange part.

The first end phase shield 322 is provided with a first base 322a and a first extension 322b integrally. The first base portion 322 a is a portion facing the end phase detection element 311. For example, the first base 322a has a length in the X direction that is the same as that of the first interposed shield 321. Therefore, the length of the first end phase shield 322 in the X direction is longer than that of the first intermediate shield 321 because the first extension portion 322b is included.

That is, it can be said that the first end-phase shield 322 includes a portion (first extension portion 322b) having a length X2 longer than the length X1 in the X direction as a magnetic field exchange portion. The length X2 is the length from the facing portion of the end phase detection element 311 to the outermost end where a leakage magnetic field is generated. On the other hand, the length X1 is a length from the facing portion of the intervening detection element 310 in the first intervening shield 321 to the end on the most end side.

Further, the intervening detection element 310 is arranged so that the first intervening shield 321 faces the center of the first intervening shield 321 in the X direction. On the other hand, the end phase detection element 311 is arranged so that the first end phase shield 322 faces a position shifted from the center of the first end phase shield 322 in the X direction. Specifically, the end phase detection element 311 is disposed to face the position shifted from the center of the first end phase shield 322 to the side opposite to the endmost portion. Since the same applies to the second end phase shield 332, the description can be applied with reference to the description of the first end phase shield 322.

Thus, in the current sensor 400, the both-end phase shields 322 and 332 are provided with the extension portions 322b and 332b. As a result, in the current sensor 400, the leakage magnetic field from the extreme end portion in the X direction in the both-end phase shields 322 and 332 reaches the opposite-side end- phase shields 322 and 332 that are opposed to each other than the end-phase detection element 311. It becomes easy. In other words, the current sensor 400 can suppress the leakage magnetic field from the extreme end in the X direction in the double- phase shields 322 and 332 from entering the space between the double- phase shields 322 and 332. For this reason, the current sensor 400 can suppress the leakage magnetic field from reaching the end phase detection element 311 and can detect the current with high accuracy.

In this embodiment, the current sensor 400 in which the extension portions 322b and 332b are provided in both the first end-phase shield 322 and the second end-phase shield 332 is employed. However, the present disclosure is not limited to this, and can be adopted as long as it is provided on at least one of the first end phase shield 322 and the second end phase shield 332.

Hereinafter, the third embodiment to the fifth embodiment of the present disclosure will be described. The second embodiment and the third to fifth embodiments can be implemented independently, but can also be implemented in appropriate combination. The present disclosure is not limited to the combinations shown in the embodiments, and can be implemented by various combinations.

(Third embodiment)
The current sensor 410 of this embodiment will be described with reference to FIG. FIG. 38 is a cross-sectional view corresponding to FIG. The current sensor 410 is different from the current sensor 400 in the configuration of the end phase shields 323 and 333. Here, the difference from the current sensor 400 will be mainly described.

The first end phase shield 323 includes a first base 323a and a first protrusion 323b. The first protrusion 323b is a part that performs magnetic field exchange between the first end-phase shield 323 and the second end-phase shield 333, and corresponds to a magnetic field exchange unit. Similarly, the 2nd end phase shield 333 contains the 2nd base 333a and the 2nd projection part 333b. The second protrusion 333b is a part that performs magnetic field exchange between the second end-phase shield 333 and the first end-phase shield 323, and corresponds to a magnetic field exchange unit. The first end phase shield 323 corresponds to a first shield. The second end phase shield 333 corresponds to a second shield.

The first base portion 323a is a flat plate-like portion facing the end phase detection element 311 as in the first base portion 322a of the above embodiment. The first protruding portion 323b is a portion bent from the end portion of the first base portion 323a toward the second end phase shield 333 side. Here, the end portion of the first base portion 323a is an end portion on the opposite side to the side facing the first interposed shield 321. Therefore, the first end shield 323 has an L shape in the XZ plane. Since the same applies to the second end phase shield 333, it can be applied with reference to the description of the first end phase shield 323.

In this manner, the end phase shields 323 and 333 serve as magnetic field exchange portions by bending portions ( protrusions 323b and 333b) bent toward the opposite end phase shields 323 and 333 rather than the facing portion of the end phase detection element 311. I have. Therefore, in the current sensor 410, the Z-direction interval Z2 between the first protrusion 323b and the second protrusion 333b is shorter than the Z-direction interval Z1 between the first intermediate shield 321 and the second intermediate shield 331. ing. The Z-direction interval Z1 is the interval between the surface opposite to the surface facing the bus bar 340 in the first interposed shield 321 and the surface opposite to the surface facing the interposed detection element 310 in the second interposed shield 331.

The current sensor 410 can achieve the same effects as the current sensor 400. Furthermore, since the current sensor 410 has the end phase shields 323 and 333 bent, the physique in the X direction can be made smaller than the current sensor 400.

(Modification 1)
With reference to FIG. 39, the current sensor 420 according to the first modification of the third embodiment will be described. FIG. 39 is a cross-sectional view corresponding to FIG. The current sensor 420 is different from the current sensor 410 in the configuration of the end phase shields 324 and 334. Here, the difference from the current sensor 410 will be mainly described.

Unlike the first end phase shield 323, the first end phase shield 324 has a flat plate shape. On the other hand, the second end phase shield 334 includes a second base portion 334a and a second protrusion 334b. The second end phase shield 334 has an L shape similarly to the second end phase shield 333. The second protrusion 334b is a part that performs magnetic field exchange between the second end-phase shield 334 and the first end-phase shield 324, and corresponds to a magnetic field exchange unit. The first end phase shield 324 corresponds to the first shield. The second end phase shield 334 corresponds to a second shield.

The current sensor 420 can achieve the same effect as the current sensor 410. That is, the current sensor 420 can achieve the same effect as the current sensor 410 as long as at least one of the end- phase shields 324 and 334 has a portion corresponding to the magnetic field exchange unit.

(Modification 2)
With reference to FIG. 40, the current sensor 430 of Modification 2 in the third embodiment will be described. 40 is a cross-sectional view corresponding to FIG. The current sensor 430 is different from the current sensor 410 in the configuration of the end phase shields 325 and 335. Here, the difference from the current sensor 410 will be mainly described.

The first end shield 325 includes a first base 325a and a first bent portion 325b. The first bent portion 325b is a portion that performs magnetic field exchange between the first end-phase shield 325 and the second end-phase shield 335, and corresponds to a magnetic field exchange portion. Similarly, the second end phase shield 335 includes a second base portion 335a and a second bent portion 335b. The second bent portion 335b is a portion that performs magnetic field exchange between the second end phase shield 335 and the first end phase shield 325, and corresponds to a magnetic field exchange portion. The first end shield 325 corresponds to the first shield. The second end phase shield 335 corresponds to a second shield.

The first base portion 325a is a flat plate-like portion similar to the first base portion 322a and is opposed to the end phase detection element 311. The first bent portion 325b is a portion bent from the end portion of the first base portion 325a toward the second end phase shield 335 side. Here, the end portion of the first base portion 325a is an end portion on the opposite side to the side facing the first interposed shield 321.

Further, unlike the first end phase shield 323, the first end phase shield 325 has a first bent portion 325b bent in a curved shape. That is, as for the 1st end phase shield 325, a part of surface facing the bus bar 340 and a part of the opposite surface are curved surfaces. The first end shield 325 can be manufactured, for example, by bending a flat shield plate by pressing or the like. Since the same applies to the second end phase shield 335, the description can be applied with reference to the description of the first end phase shield 325.

As described above, the end phase shields 325 and 335 serve as magnetic field exchange portions by bending portions ( bent portions 325b and 335b) bent toward the opposite end phase shields 325 and 335 rather than the facing portion of the end phase detection element 311. I have. The current sensor 430 can achieve the same effect as the current sensor 410.

(Fourth embodiment)
The current sensor 440 according to the fourth embodiment will be described with reference to FIGS. 41 and 42. The current sensor 440 is different from the current sensor 400 in that a shield configuration, a circuit board 350, and a housing 360 are provided. Here, the difference from the current sensor 400 will be mainly described.

The current sensor 440 includes a circuit board 350 and a housing 360 as shown in FIG. The circuit board 350 is electrically connected to the magnetic detection elements 310 and 311, and sensor signals from the magnetic detection elements 310 and 311 are input. More specifically, the circuit board 350 is formed with circuit elements, conductive wirings, and the like, and the magnetic detection elements 310 and 311 are mounted thereon. In the circuit board 350, the magnetic detection elements 310 and 311 are electrically connected to a part of the wiring. The surface on which the magnetic detection elements 310 and 311 are mounted on the circuit board 350 can be said to be a mounting surface.

Furthermore, the circuit board 350 has through holes formed in the stacking direction. This through hole is a hole into which a fixing member 337a described later is inserted. And the through hole is provided in the circuit board 350 in the position which opposes the fixing hole 337 demonstrated later.

The housing 360 is made of, for example, resin, and integrally holds the first shield and the bus bar 340. The housing 360 can integrally hold the first shield and the bus bar 340 by insert molding or insertion. Hereinafter, the housing 360 that integrally holds the first shield and the bus bar 340 is referred to as a structure.

Further, the housing 360 is provided with a hole for fixing the fixing member 337a at a portion facing the circuit board 350. This hole is provided at a position facing the fixing hole 337. In addition, a female screw corresponding to the fixing member 337a, which is a male screw, for example, can be used for this hole.

As shown in FIG. 42, the first shield has a first thin portion 326 that is thinner than the first intermediate shield 321 and the first end-phase shield 322 in addition to the first intermediate shield 321 and the first end-phase shield 322. Is included. In the first shield, the first intervening shield 321 and the first end-phase shield 322 are integrally configured via the first thin portion 326. That is, the 1st shield has the structure connected by the 1st thin part 326 for every phase. Note that the first intervening shield 321 and the first end-phase shield 322 can be referred to as thick portions with respect to the first thin portion 326.

For this reason, the first shield has a shape in which a recess is formed on the surface on the magnetic detection element 310, 311 side. Further, as shown in FIG. 42, the first shield is provided such that the surface on which the concave portion is formed is opposed to the surface opposite to the mounting surface of the circuit board 350. Here, the thickness is a thickness in the stacking direction.

Similarly, the second shield includes a second thin portion 336 that is thinner than the second intermediate shield 331 and the second end-phase shield 332 in addition to the second intermediate shield 331 and the second end-phase shield 332. . In the second shield, the second intervening shield 331 and the second end-phase shield 332 are integrally formed via the second thin portion 336.

Furthermore, in the second end phase shield 332, a fixing hole 337 penetrating in the stacking direction is formed in the second extension 332b. As shown in FIG. 41, for example, fixing holes 337 are formed at the four corners of the second phase shield 332. The fixing hole 337 is a hole into which a fixing member 337a for integrally fixing the second shield, the circuit board 350, and the housing 360 is inserted.

In the current sensor 440, the structure, the circuit board 350, and the second shield are stacked in this order. In the current sensor 440, the laminated structure, the circuit board 350, and the second shield are fixed by a fixing member 337a. That is, it can be said that the components of the respective phases P1 to Pn are integrally configured via the circuit board 350 and the housing 360. The structure integrally configured in this way can also be called a sensor terminal block.

The current sensor 440 can achieve the same effect as the current sensor 400. The current sensor 440 can achieve the same effect as the current sensor 400 even if it does not include the circuit board 350, the housing 360, the fixing member 337a, and the like.

Furthermore, since the current sensor 440 includes the second extension 332b, a fixing hole 337 can be formed in the second extension 332b. That is, the current sensor 440 can be fixed to the circuit board 350, the housing 360, or the like while using a configuration for high accuracy of current detection. For this reason, the current sensor 440 is preferable to a case where the size of the current sensor 440 is increased only for fixing to the circuit board 350, the housing 360, and the like.

Note that the current sensor 440 can be employed even if the end- phase shields 322 and 332 and the intervening shields 321 and 331 are separated, like the current sensor 400 and the like. In this case, the second interposed shield 331 can be fixed to the circuit board 350 by an adhesive, screwing, or the like. Furthermore, the current sensor 440 can be employed even if the end phase shields 322 and 332 are bent, like the current sensor 410 and the like.

Further, the circuit board 350 may be provided with a circuit element on the opposite surface of the mounting surface. The current sensor 440 can be reduced in size by assembling the current sensor 440 into the recess formed in the second shield so that the circuit element on the opposite surface is disposed. That is, the current sensor 440 can reduce the size of at least one of the X direction and the Y direction as compared with the case where the circuit element on the opposite surface is disposed outside the opposing region of the second shield.

(Fifth embodiment)
A current sensor 450 according to the fifth embodiment will be described with reference to FIG. 43 is a cross-sectional view corresponding to FIG. The current sensor 450 is different from the current sensor 400 in the configuration of the first shield and the second shield. Here, the difference from the current sensor 400 will be mainly described.

The current sensor 450 includes a third shield 338 as a magnetic shield part in addition to the intervening shields 321 and 331. The third shield 338 is made of a magnetic material, like the intervening shields 321 and 331. The third shield 338 mainly shields a magnetic field from the outside with respect to the end phase detection element 311. The third shield 338 includes a first base 338a, a second base 338b, and a side wall 338c.

The first base 338a and the second base 338b correspond to end-phase shields. The first base portion 338a is disposed to face the bus bar 340. On the other hand, the second base portion 338 b is disposed to face the end phase detection element 311. Both base portions 338a and 338b are flat portions parallel to the XY plane. Thus, it can be said that the third shield 338 includes the first base portion 338a corresponding to the first end phase shield and the second base portion 338b corresponding to the second end phase shield.

The side wall part 338c corresponds to a magnetic field exchange part. The side wall portion 338c is a portion that is continuously provided at the end of the base portions 338a and 338b in the arrangement direction so as to exchange magnetic fields between the base portions 338a and 338b, and the base portions 338a and 338b are integrally formed. . The side wall part 338c is a flat part parallel to the YZ plane.

That is, in the third shield 338, the first base portion 338a, the second base portion 338b, and the side wall portion 338c are configured as a single body. Therefore, as shown in FIG. 43, the third shield 338 has a U shape in the XZ plane.

The first interposed shield 321 and the first base portion 338a correspond to the first shield. The second interposed shield 331 and the second base 338b correspond to a second shield. The third shield 338 can also be said to be a configuration in which the first end-phase shield 322 and the second end-phase shield 332 are integrated by the side wall portion 338c.

As described above, the current sensor 450 is continuously provided at the end of the both base portions 338a and 338b in the arrangement direction, and includes the side wall portion 338c in which the base portions 338a and 338b are integrated. As a result, the current sensor 450 can reduce the occurrence of a leakage magnetic field from the ends in the arrangement direction of the both base portions 338a and 338b. For this reason, the current sensor 450 can suppress the leakage magnetic field from reaching the end phase detection element 311 and can detect the current with high accuracy.

Although the present disclosure has been described based on the embodiment, it is understood that the present disclosure is not limited to the embodiment or the structure. The present disclosure includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more or less, are within the scope and spirit of the present disclosure.

Claims (27)

1. A magnetic detection element (11-14) for detecting a magnetic flux generated from the current path (210-240) and performing magnetoelectric conversion;
   An electric current provided with at least two magnetic shields (21, 21A to 21N, 22, 22A to 22N, 23, 24) arranged around the magnetic detection element and configured to shield a magnetic flux from the outside with respect to the magnetic detection element; A sensor,
   The at least two magnetic shields have a first magnetic shield and a second magnetic shield arranged to face each other while sandwiching the magnetic detection element and the current path,
   At least one of the first magnetic shield and the second magnetic shield has at least two base portions and a connecting portion connecting the at least two base portions, and the other first magnetic shield and A current sensor in which concave portions (1, 1A, 4) recessed from the periphery are formed on a surface facing the second magnetic shield.
2. Two magnetic sensing elements provided opposite to each of the two current paths,
   The first magnetic shield and the second magnetic shield are disposed opposite to each other while sandwiching the two magnetic detection elements and the two current paths,
   The current sensor according to claim 1, wherein the concave portion is provided at a portion facing an intermediate position between the two magnetic detection elements.
3. One magnetic detection element provided opposite to the one current path,
   2. The current sensor according to claim 1, wherein the first magnetic shield and the second magnetic shield are disposed to face each other while sandwiching one magnetic detection element and one current path.
4. The current sensor according to any one of claims 1 to 3, wherein the recess is formed in each of the first magnetic shield and the second magnetic shield.
5. The current sensor according to any one of claims 1 to 4, wherein the concave portion is formed at a position facing the connecting portion.
6. The connecting portion is provided so as to protrude to the opposite side of a facing region that is a region sandwiched between the first magnetic shield and the second magnetic shield,
   The current sensor according to claim 5, wherein the recess is formed deeper than a thickness of at least one of the first magnetic shield and the second magnetic shield in which the recess is formed.
7. The current sensor according to claim 5 or 6, wherein the recess has a shape in which a side wall is inclined so that an opening area becomes wider from a bottom toward an opening end.
8. The current sensor according to any one of claims 1 to 7, wherein a heat radiating member is embedded in the recess.
9. At least one of the first magnetic shield and the second magnetic shield is a laminate of a plurality of layers, and is the outermost layer on the opposite side of the facing region sandwiched between the first magnetic shield and the second magnetic shield. The current sensor according to any one of claims 1 to 8, which has a larger permeability than other layers.
10. At least one of the first magnetic shield and the second magnetic shield is a laminate of a plurality of layers, and is the outermost layer on the opposite side of the facing region sandwiched between the first magnetic shield and the second magnetic shield. The current sensor according to any one of claims 1 to 8, wherein the saturation magnetic flux density is larger than that of the other layers.
11. At least one of the first magnetic shield and the second magnetic shield has three or more layers laminated and covered with a resin member, and is sandwiched between the first magnetic shield and the second magnetic shield. 9. The current sensor according to claim 1, wherein the outermost layer on the opposing region side and the outermost layer on the opposite side of the opposing region have a smaller difference in linear expansion coefficient from the resin member than other layers. .
12. The recess is formed from one end to the other end of at least one of the first magnetic shield and the second magnetic shield in which the recess is formed, along a current flow direction in the current path. The current sensor according to any one of claims 1 to 11.
13. The current sensor according to any one of claims 1 to 11, wherein the concave portion is a bottomed hole portion surrounded by a bottom portion and an annular side wall.
14. An upper phase in which two or more current paths are arranged and a lower phase in which two or more current paths are arranged are stacked in the thickness direction of the magnetic shield,
    The magnetic detection elements include two or more upper phase magnetic detection elements provided to face each of the current paths in the upper phase, and two provided to face each of the current paths in the lower phase. With at least two lower phase magnetic sensing elements,
    The at least two magnetic shields include a first upper phase magnetic shield and a second upper phase magnetic shield sandwiching the current path in the upper phase and the upper phase magnetic sensing element, and the current path and the lower phase in the lower phase. The current sensor according to claim 1, further comprising a first lower-phase magnetic shield and a second lower-phase magnetic shield that sandwich the magnetic detection element.
15. One of the lower phase side of the first upper phase magnetic shield and the second upper phase magnetic shield is integrated with one of the upper phase side of the first lower phase magnetic shield and the second lower phase magnetic shield. The current sensor according to claim 14, wherein the current sensor constitutes an intermediate magnetic shield.
16. The current sensor according to claim 15, wherein the intermediate magnetic shield is provided with a nonmagnetic portion in a region facing the current path on the upper phase side and the current path on the lower phase side.
17. Having two or more magnetic sensing elements provided opposite to each of the two or more current paths;
    Each of the first magnetic shield and the second magnetic shield includes a surface layer portion (21M1, 22M1, 21N1, 22N1) including the connecting portion and an end layer portion provided in continuity with the connecting portion in each base portion; And a protruding portion (21M2, 22M2, 21N2, 22N2) protruding from the end layer portion in each base portion, and the recess is formed between the protruding portions,
    The protrusion of the first magnetic shield is disposed opposite the protrusion of the second magnetic shield;
    Each magnetic detection element is individually disposed in a facing region of the projecting portion disposed to face each other,
    The first magnetic shield is configured so that the leakage magnetic field from the recess in the first magnetic shield and the leakage magnetic field from the recess in the second magnetic shield cancel each other so that the leakage magnetic field does not reach the magnetic detection element. The current sensor according to claim 1, wherein a shape of at least one of the second magnetic shield is adjusted.
18. 18. The current according to claim 17, wherein at least one of the first magnetic shield and the second magnetic shield has a thickness of the surface layer portion with respect to a total thickness of the surface layer portion and the protrusion as the shape. Sensor.
19. The current sensor according to claim 17 or 18, wherein at least one of the first magnetic shield and the second magnetic shield has the shape, and an interval between the protruding portions adjacent to each other via the concave portion is adjusted.
20. The base parts that are adjacent to each other via the connecting part are connected to each other only through a part of the opposing part,
    20. The current sensor according to claim 17, wherein at least one of the first magnetic shield and the second magnetic shield has the shape, and the length of the connecting portion at the facing portion is adjusted. .
21. Having three magnetic sensing elements provided facing each of the three current paths;
    Each of the first magnetic shield and the second magnetic shield has three base portions facing the three magnetic detection elements,
    The leakage magnetic field from the concave portion in the first magnetic shield and the leakage magnetic field from the concave portion in the second magnetic shield cancel each other, and the leakage magnetic field is the two magnetisms of the three magnetic detection elements. The shape of at least one of the first magnetic shield and the second magnetic shield is adjusted so as not to reach one magnetic detection element sandwiched between the detection elements. The current sensor described.
22. A current sensor for individually detecting a current flowing through each of the plurality of current paths (340);
    A magnetic detection element (310, 311) disposed opposite to one of the current paths to detect a magnetic field generated from the current path and convert it into an electrical signal;
    A magnetic field from the outside to the magnetic detection element is shielded, and a pair of first shields (321 to 325) and second shields (331 to 331) arranged to face each other while sandwiching the current path and the magnetic detection element. 335) corresponding to each of the plurality of current paths, each phase including the first shield, the current path, the magnetic detection element, the first 2 shields are laminated in this order in the laminating direction, and arranged in an arrangement direction perpendicular to the laminating direction,
    Among the plurality of phases, an end phase in the arrangement direction is an end phase,
    The first shield in the end phase is a first end phase shield (322 to 325),
    The second shield in the end phase is a second end phase shield (332 to 335),
    The magnetic detection element in the end phase is an end phase detection element (311),
    At least one of the first end phase shield and the second end phase shield has a leakage magnetic field from one end of the first end phase shield and the second end phase shield in the arrangement direction. Magnetic field exchange for exchanging the magnetic field between the first end-phase shield and the second end-phase shield so that it can reach the other of the first end-phase shield and the second end-phase shield more easily than the detection element. Current sensor including a portion (322b, 323b, 325b, 332b to 335b).
23. A current sensor for individually detecting a current flowing through each of the at least three current paths (40),
    The first shield in the phase other than the end phase is a first interposed shield (321),
    The second shield in the phase other than the end phase is a second interposed shield (331),
    The magnetic detection element sandwiched between the first interposed shield and the second interposed shield is an interposed detection element (310),
    At least one of the first end-phase shield and the second end-phase shield is configured such that the leakage magnetic field is generated from the facing portion of the end-phase detection element in the arrangement direction as the magnetic field exchange unit (322b, 332b). A length of the first intermediate shield and the second intermediate shield corresponding to the first intermediate shield and the second intermediate shield is longer than a length from an opposing portion of the intermediate detection element to an end on the extreme end side. The current sensor according to claim 22.
24. At least one of the first end-phase shield and the second end-phase shield corresponds to the first end corresponding to the magnetic field exchanging portion (323b, 325b, 333b to 335b) rather than the facing portion of the end-phase detection element. The current sensor according to claim 22, further comprising a portion bent toward the other side of the phase shield and the second end phase shield.
25. The current sensor according to any one of claims 22 to 24, wherein each of the first shield and the second shield has a configuration divided for each of the plurality of phases.
26. Each of the first shield and the second shield is connected to each of the plurality of phases by a thin portion (326, 336) having a smaller thickness in the stacking direction than the first shield and the second shield. The current sensor according to any one of claims 22 to 24.
27. A current sensor for individually detecting a current flowing through each of the plurality of current paths (340);
    A magnetic detection element (310, 311) disposed opposite to one of the current paths to detect a magnetic field generated from the current path and convert it into an electrical signal;
    A magnetic field from the outside to the magnetic detection element is shielded, and a pair of first shield (321, 338a) and second shield (331, 331) arranged opposite to each other while sandwiching the current path and the magnetic detection element. 338b), and a plurality of phases having a plurality of phases corresponding to each of the plurality of current paths,
    In each phase, the first shield, the current path, the magnetic detection element, and the second shield are stacked in this order in the stacking direction, and are disposed in the layout direction orthogonal to the stacking direction,
    Among the plurality of phases, an end phase in the arrangement direction is an end phase,
    The first shield in the end phase is a first end phase shield (338a),
    The second shield in the end phase is a second end phase shield (338b),
    The magnetic detection element in the end phase is an end phase detection element (311),
    The magnetic shield portion is continuous with the end portion in the arrangement direction of the first end-phase shield and the second end-phase shield in order to exchange magnetic fields between the first end-phase shield and the second end-phase shield. A current sensor provided with a magnetic field exchanging part (338c) that is provided as a unit and that integrates the first end-phase shield and the second end-phase shield.

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