JP2007183221A - Electric current sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coreless electric current sensor that does not need core layout allowing current value to be measured based on a magnetic field occurring around a conduction member. <P>SOLUTION: The electric current sensor comprises the conduction members 11 having adjacent parallel sections where current I to be measured flows in the opposite direction, and a magnetoelectric device 12 that is arranged between the conduction members forming adjacent parallel sections 11, detects the magnetic field occurring around the conduction members 11 by flowing of the current I to be measured through the conduction members 11, and outputs an electric signal according to the magnetic field. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a current sensor that measures a current value based on a magnetic field generated when a current to be measured flows through a conducting member, and particularly to a magnetic proportional current sensor.

  When the current to be measured flows through the conducting member, the magnetic sensor disposed in the vicinity of the conducting member is detected by the magnetic sensor generated around the conducting member, and output according to the magnitude of the magnetic field detected by the magnetic sensor. In a magnetic proportional current sensor that measures the current value of a current to be measured based on an electrical signal, for example, when a core for focusing a magnetic field is not disposed, there is a magnetic field that the magnetic sensor can detect and function. It may not be obtained.

Therefore, for example, in the current sensor 100 disclosed in Japanese Patent Application Laid-Open No. 2004-255793 (Patent Document 1), as shown in FIG. 12, a gap 53 is partially formed, and the magnetic sensor 52 is disposed in the gap 53. The core 51 is disposed so as to surround the conductive member 54. By arranging the core 51 in this way, the magnetic field generated around the conducting member 54 is focused on the core 51 and passes through the gap 53. Thereby, the magnetic sensor 52 can detect a magnetic field passing through the gap 53 and output an electric signal corresponding to the magnitude of the magnetic field. The current sensor 100 measures the current value I of the current to be measured based on this electrical signal.
JP 2004-257993 A

  Incidentally, disposing the core 51 so as to surround the conductive member 54 is useful for focusing the magnetic field generated around the conductive member 54, but the current sensor 100 is large due to the arrangement of the core 51 itself. There was a problem of becoming. In addition, a fixing member for fixing the core 51 may be required, and the number of parts of the current sensor 100 increases, which causes a problem of increase in cost and weight.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to obtain a magnetic field large enough for the magnetic sensor to detect and function without arranging the core. The object is to provide a coreless current sensor.

  In order to solve the above-described problem, the current sensor according to claim 1 is disposed between a conductive member in which an adjacent parallel portion in which a current to be measured flows in the opposite direction is formed and a conductive member that forms the adjacent parallel portion, And a magneto-electric conversion element that detects a magnetic field generated around the conducting member when a current to be measured flows through the conducting member and outputs an electrical signal corresponding to the magnetic field.

  According to the first aspect of the present invention, the current value of the current to be measured can be measured based on the magnetic field generated around the conductive member that forms the adjacent parallel portion. That is, it is possible to realize a coreless current sensor that does not require a core arrangement.

  The current sensor according to claim 2 is characterized in that the conducting member is formed of a flat plate, and the adjacent parallel portion is formed by bending the flat plate. According to the second aspect of the present invention, the coreless current sensor can be realized by bending the flat conductive member to form the adjacent parallel portion.

  In the current sensor according to claim 3, the conductive member is formed of a plurality of conductor pieces, and the adjacent parallel portion is formed of first and second conductor pieces arranged to face each other so as to be substantially parallel. The first and second conductor pieces are connected via a third conductor piece connected to one end of each of the first and second conductor pieces.

  According to the third aspect of the present invention, a coreless current sensor can be realized by forming the adjacent parallel portions by arranging the first and second conductor pieces so as to be substantially parallel to each other. .

  The current sensor according to claim 4 is characterized in that the magnetoelectric conversion element is narrower than the conducting member and is disposed so as to be within the width of the conducting member. As a result, the magnetoelectric conversion element is less susceptible to noise such as static electricity. Therefore, it is possible to realize a coreless current sensor that is not easily affected by noise. In order to improve accuracy, it is desirable to arrange the magnetoelectric conversion element where the magnetic flux is dense. Therefore, like the current sensor according to the fifth aspect, the magnetoelectric conversion elements may be arranged at substantially equal intervals from each of the conducting members forming the adjacent parallel portions.

  The current sensor according to claim 6 is characterized in that the conductive member is arranged so as to constitute each side of the rectangle to form two sets of adjacent parallel portions, and the magnetoelectric conversion element is arranged in the rectangle. And According to the invention described in claim 6, two sets of adjacent parallel portions are formed in the conducting member by arranging the conducting member so that the conducting member constitutes each side of the rectangle. Therefore, if the magnetoelectric conversion element is arranged in this rectangle, a coreless current sensor can be realized in which the magnetoelectric conversion element can detect magnetic fields from four directions.

  The current sensor according to claim 7 is characterized in that the conducting member includes a plurality of adjacent parallel portions, and the magnetoelectric conversion elements are respectively disposed between the conducting members forming the plurality of adjacent parallel portions. According to the seventh aspect of the present invention, adjacent parallel portions are continuously formed, and each magnetoelectric conversion element arranged in each adjacent parallel portion detects a magnetic field in the opposite direction alternately in the arrangement order. By the way, each detected magnetic field is affected by noise such as static electricity, and even if each electrical signal output from the magnetoelectric transducer according to each magnetic field is affected by noise, If the averaging calculation is performed, the influence of noise on the electric signal can be reduced. As a result, a coreless current sensor that is less susceptible to noise can be realized.

  The current sensor according to claim 8 is characterized in that a magnetic current collecting plate made of a magnetic material is disposed on one surface side of the magnetoelectric conversion element. Thereby, it is possible to obtain substantially the same effect as the sensitivity of the magnetoelectric conversion element to the magnetic field is improved. Therefore, it is possible to realize a coreless current sensor that does not require a core arrangement. As in the current sensor according to the ninth aspect, when the magnetism collecting plate is arranged avoiding the sensor portion of the magnetoelectric conversion element, the magnetoelectric conversion element can detect the magnetic field more effectively.

  The current sensor according to claim 10 includes a shielding material made of a nonmagnetic metal that shields noise from the outside, and the shielding material is formed between conductive members that form adjacent parallel portions so as to cover the magnetoelectric conversion element. It is characterized by being arranged. According to the invention described in claim 10, by arranging the shielding material so as to cover the magnetoelectric conversion element, it is possible to prevent noise such as static electricity from being detected together when the magnetoelectric conversion element detects a magnetic field. be able to. As in the current sensor according to claim 11, the shielding effect can be further improved by grounding the shielding material.

  According to a twelfth aspect of the present invention, the magnetoelectric conversion element is a vertical Hall element. The vertical Hall element can be formed relatively thin. Therefore, according to the twelfth aspect of the present invention, the width between the conductive members forming the adjacent parallel portions can be reduced. When the width between the conducting members is narrowed, the magnetoelectric conversion element and each conducting member can be brought close to each other, so that the magnetoelectric conversion element can detect the magnetic field generated around the conducting member in a stronger state. Further, when the width between the conductive members is narrowed, the coreless current sensor can be reduced in size. Further, when the width between the conductive members is narrowed, it is difficult for noise (for example, static electricity) from the outside to enter, so that it is possible to prevent the vertical Hall element from outputting an electric signal including an error due to noise. As in the current sensor according to the thirteenth aspect, a coreless current sensor can be realized even if the magnetoelectric conversion element is a magnetoresistive element.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or is equivalent, and the description is abbreviate | omitted.

(First embodiment)
A current sensor 10 according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a schematic perspective view of the current sensor 10, and FIG. 1B is a schematic cross-sectional view taken along line II shown in the schematic perspective view of the current sensor 10 shown in FIG. As shown in FIG. 1A, the current sensor 10 in the present embodiment includes a conductive member 11 and a magnetoelectric conversion element 12.

  The current sensor 10 detects a magnetic field generated around the conducting member 11 when the current I to be measured flows through the conducting member 11, and outputs an electric signal corresponding to the magnetic field to an external device (not shown). Thus, the current value of the current I to be measured is measured. The current sensor 10 includes the magnetoelectric conversion element 12 and the like housed in the housing, but the housing is not shown.

  The conducting member 11 is formed by, for example, pressing a metal plate made of a conductor such as copper or copper alloy, and bending the obtained flat conducting member so that at least one adjacent parallel portion is formed. Hereinafter, each part of the conductive member 11 will be described with reference numerals 11a to 11e. In addition, as for the conduction | electrical_connection member 11, you may comprise each of each conduction | electrical_connection member 11a-11e with a conductor piece.

  One end of the conducting member 11 is connected to a current supply source (not shown), and the conducting member 11 constitutes a current path of the current I to be measured. When the current I to be measured flows through the conducting member 11, a magnetic field substantially proportional to the magnitude of the current to be measured is generated around the conducting member 11, as will be described later. A magnetic field generated around the conducting member 11 is detected by the magnetoelectric conversion element 12, and the magnetoelectric conversion element 12 outputs an electric signal corresponding to the magnetic field to an external device (not shown).

  As shown in FIG. 1 (b), the conducting member 11 is bent or arranged in a substantially convex shape in cross section, and adjacent parallel portions are formed so as to face each other so as to be substantially parallel with the interval D maintained. . The adjacent parallel portions are formed by conducting members 11a and 11b, and the conducting members 11a and 11b are electrically connected via a conducting member 11c that forms a bent portion. A magnetoelectric conversion element 12 is disposed between the conducting members 11a and 11b that form adjacent parallel portions. In arranging the magnetoelectric conversion element 12, they are arranged at substantially equal intervals from each of the conduction members 11 a and 11 b.

  The magnetoelectric conversion element 12 is narrower than the conducting member 11 and is disposed so as not to protrude from the width frame of the conducting member 11. The magnetoelectric conversion element 12 is mounted on a substrate (not shown), and is electrically connected to an external device (not shown) through the substrate (not shown). Examples of the magnetoelectric conversion element 12 include a giant magnetoresistive element (GMR), an anisotropic magnetoresistive element (AMR), and a tunneling magnetoresistive element (TMR) represented by a tunneling magnetoresistive element (TMR). Any of a resistance element, a vertical Hall element, or a horizontal Hall element can be used. In the current sensor 10 of the present embodiment, it is preferable to use a vertical Hall element for the reason described later. Therefore, hereinafter, the magnetoelectric conversion element will be described as a vertical Hall element.

  As shown by a straight arrow in FIG. 1B, when the current I to be measured flows through the conducting member 11 from below (conducting member 11d) to above (conducting member 11e), the conducting member 11a The measurement current I flows from the right to the left of the page. Further, in the conducting member 11b, the current I to be measured flows from the left to the right of the page. That is, in the conducting members 11a and 11b that form adjacent parallel portions, the current I to be measured flows in the opposite direction. Then, magnetic fields Ba and Bb based on the current I to be measured are generated around the conductive members 11a and 11b.

  At this time, each of the magnetic fields Ba and Bb passes through the vertical Hall element 12. Since the magnetic fields Ba and Bb have directionality from the front surface to the back surface between the conducting members 11a and 11b, as a result, the vertical Hall element 12 responds to the magnetic field B that is the sum of the magnetic fields Ba and Bb. The electrical signal is output to an external device (not shown). And based on this electrical signal, the current value of the current I to be measured can be measured.

  Next, the reason why the vertical Hall element is preferable as the magnetoelectric conversion element in the current sensor 10 in the present embodiment will be described.

  First, the operating characteristics of the vertical Hall element will be described. FIG. 11 is a diagram illustrating an example of the vertical Hall element 12a. FIG. 11A is a schematic top view of the vertical Hall element 12a. FIG.11 (b) is a schematic sectional drawing in the rule line of a top view. In both FIGS. 11A and 11B, the magnetic field B to be detected by the vertical Hall element 12a is assumed to be directed from the left to the right toward the paper surface.

  In the vertical Hall element 12 a as the magnetoelectric conversion element 12, a hole plate portion 52 t is formed perpendicular to the surface of the semiconductor substrate 51, and carriers flow in a direction perpendicular to the surface of the semiconductor substrate 51. 11A and 11B, an n-type low-concentration diffusion layer (n−) 52 is separated by a p-type high-concentration layer 54b, and a hole plate is formed on the surface of the semiconductor substrate 51. The part 52t is formed vertically.

  As shown by the broken-line arrows in FIG. 11B, carriers are connected to the surface of the semiconductor substrate 51 between the terminals Ti0 and Ti1 and between the terminals Ti0 and Ti2 via the n-type high concentration buried layer 54u. Flows vertically. The element operating as the element is the hall plate portion 52t in the center, and an output voltage (hall voltage) VH generated by a magnetic field orthogonal to the hall plate portion 52t is detected between the terminals TV.

  Based on the fact that the vertical Hall element 12a has such an operation characteristic, as shown in FIG. 1B, between the conducting members 11a and 11b forming the adjacent parallel portions, the surface is directed from the front surface to the back surface. If the vertical Hall element 12a is arranged so that the Hall plate portion 52t is orthogonal to the magnetic field B generated in the direction, the vertical Hall element 12a can efficiently output an electrical signal corresponding to the magnetic field B. Can do.

  Further, since the thickness of the vertical Hall element 12a can be made thinner than the thickness of the conventional horizontal Hall element or magnetoresistive element, the conductive members 11a and 11b in which the vertical Hall element 12a is arranged are arranged. The interval D between them can be reduced. By reducing the distance D between the conducting members 11a and 11b, the vertical Hall element 12a can detect a magnetic field in a stronger state. As a result, the magnetic field detection capability (sensitivity) of the vertical Hall element 12a. An effect equivalent to that improved can be obtained.

  Further, by reducing the interval D, noise (for example, static electricity) is less likely to invade, so that it is possible to prevent the vertical Hall element 12a from outputting an electric signal including an error due to the noise.

  As described above, according to the current sensor 10 in the present embodiment, it is based on the magnetic field generated around the conducting members 11a and 11b that form the adjacent parallel portions without arranging the core for focusing the magnetic field. A coreless current sensor that can measure the current value of the current I to be measured can be realized.

(Second Embodiment)
A current sensor 20 according to a second embodiment of the present invention will be described with reference to FIGS. 2 (a), (b), and (c). 2A is a schematic perspective view of the current sensor 20, FIG. 2B is a schematic cross-sectional view taken along the line of the schematic perspective view, and FIG. FIG.

  As shown in FIG. 2A, the current sensor 20 in the present embodiment includes a conductive member 11 and a vertical Hall element 12 as a magnetoelectric conversion element. Hereinafter, each part of the conductive member 11 will be described with reference numerals 11a to 11e.

  As shown in FIG. 2 (b), the current sensor 20 in the present embodiment is configured such that when the vertical Hall element 12 is disposed between the conductive members 11a and 11b that form adjacent parallel portions, a conductive portion that forms a bent portion. This is an example of arrangement in the vicinity of the member (conductor fragment) 11c.

  As shown by a straight arrow in FIG. 2B, when the current I to be measured flows through the conductive member 11 from below (conductive member 11d) to above (conductive member 11e), the conductive member 11a The measurement current I flows from the right to the left of the page. Further, in the conducting member 11b, the current I to be measured flows from the left to the right of the page. That is, in the conducting members 11a and 11b that form adjacent parallel portions, the current I to be measured flows in the opposite direction. Further, in the conducting member 11c that forms the bent portion, the current I to be measured flows from the bottom to the top of the page. Then, magnetic fields Ba to Bc based on the current I to be measured are generated around the conducting members 11a to 11c.

  At this time, each of the magnetic fields Ba to Bc from the three directions passes through the vertical Hall element 12. Since the magnetic fields Ba to Bc have directionality from the front surface to the back surface between the conducting members 11a and 11b, as a result, the vertical Hall element 12 responds to the magnetic field B that is the sum of the magnetic fields Ba to Bc. The electrical signal is output to an external device (not shown). The current sensor 20 in the present embodiment can measure the current value of the current I to be measured based on this electrical signal.

  Therefore, according to the current sensor 20 in the present embodiment, the conductive members 11a and 11b that form the adjacent parallel portions and the conductive members (conductor fragments) that form the bent portions without arranging the core for focusing the magnetic field. A coreless current sensor that can measure the current value of the current I to be measured can be realized based on the magnetic field generated around 11c.

  As shown in the vertical Hall element 12 shown in FIG. 2C, a sensor portion 12s composed of an n-type low-concentration diffusion layer (n−) 52 and a p-type high-concentration layer 54b is arranged at 5 to 1000 μm from the element end. If provided, the vertical Hall element 12 can more effectively detect the magnetic fields Ba to Bc.

(Third embodiment)
A current sensor 30 according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 3A is a schematic perspective view of the current sensor 30, and FIG. 3B is a schematic cross-sectional view taken along the line ha-ha of the schematic perspective view.

  The current sensor 30 in this embodiment is an example in which the shape of the conducting member 11 in the current sensors 10 and 20 in the first and second embodiments is changed, as shown in FIG. Hereinafter, description will be given with reference numerals 11 a to 11 c, 11 d 1, 11 d 2, 11 e 1, and 11 e 2 assigned to the respective parts of the conductive member 11.

  As shown in FIG. 3B, the conductive member 11 is arranged in a substantially rectangular shape so that two sets of adjacent parallel portions are formed. That is, an adjacent parallel portion formed by the conductive members 11a and 11b and an adjacent parallel portion formed by the conductive members 11c and 11e2 are formed. A vertical Hall element 12 as a magnetoelectric conversion element is disposed in a rectangle surrounded by the two sets of adjacent parallel portions.

  In arranging the vertical Hall element 12, the distance between the vertical Hall element 12 and the conductive member 11a and the distance between the vertical Hall element 12 and the conductive member 11b are substantially equal. Further, the interval between the vertical Hall element 12 and the conductive member Bc and the interval between the vertical Hall element 12 and the conductive member Be2 are substantially equal.

  As shown by a straight arrow in FIG. 3B, when the current I to be measured flows through the conducting member 11 from below (conducting member 11d1) to above (conducting member 11e1), the conducting member 11a The measurement current I flows from the top to the bottom of the page. In the conducting member 11b, the current I to be measured flows from the bottom to the top of the page. That is, in the conducting members 11a and 11b that form adjacent parallel portions, the current I to be measured flows in the opposite direction.

  Further, in the conducting member 11c, the current I to be measured flows from the right to the left of the page. Further, in the conducting member 11e2, the current I to be measured flows from the left to the right of the page. That is, in the conducting members 11c and 11e2 that form adjacent parallel portions, the measured current I flows in the opposite direction. Then, magnetic fields Ba to Bc and Be2 based on the current I to be measured are generated around the conducting members 11a to 11c and 11e2. At this time, each of the magnetic fields Ba to Bc and Be2 from the four directions passes through the vertical Hall element 12.

  The magnetic fields Ba to Bc and Be2 have directionality from the front surface to the back surface in the portion surrounded by the conducting members 11a to 11c and 11e2. As a result, the vertical Hall element 12 has the magnetic fields Ba to An electric signal corresponding to the magnetic field B obtained by adding Bc and Be2 is output to an external device (not shown). The current sensor 30 in the present embodiment can measure the current value of the current I to be measured based on this electric signal.

  Therefore, according to the current sensor 30 in the present embodiment, the current value of the current I to be measured can be measured based on the magnetic field generated around the conducting member without arranging the core for focusing the magnetic field. A coreless current sensor can be realized. In addition, according to the current sensor 30 in the present embodiment, the current sensor 30 can be reduced in size by forming the conductive member 11 as shown in FIG.

(Fourth embodiment)
A current sensor 40 according to a fourth embodiment of the present invention will be described with reference to FIGS. 4 (a) and 4 (b). 4A is a schematic perspective view of the current sensor 40, and FIG. 4B is a schematic cross-sectional view taken along the knee line of the schematic perspective view.

As shown in FIG. 4A, the current sensor 40 in the present embodiment is configured to include a conductive member 11 and two magnetoelectric conversion elements 12 and 13. Hereinafter, description will be given with reference numerals 11 a to 11 c, 11 d 1, 11 d 2, 11 e 1, 11 e 2 attached to the respective parts of the conducting member 11.
As shown in FIG. 4B, the conducting member 11 includes a plurality of adjacent parallel portions. That is, an adjacent parallel portion formed by the conducting members 11a and 11b, an adjacent parallel portion formed by the conducting members 11c and 11e2, and an adjacent parallel portion formed by the conducting members 11a and 11d1 are provided.

  A vertical Hall element 12 as a magnetoelectric conversion element is disposed in a portion surrounded by the conducting members 11a to 11c and 11e2. In arranging the vertical Hall element 12, the distance between the vertical Hall element 12 and the conductive member 11a and the distance between the vertical Hall element 12 and the conductive member 11b are substantially equal. Further, the interval between the vertical Hall element 12 and the conductive member Bc and the interval between the vertical Hall element 12 and the conductive member Be2 are substantially equal. In addition, a vertical Hall element 13 as a magnetoelectric conversion element is disposed between the conductive members 11a and 11d1 that form adjacent parallel portions. The vertical Hall element 13 is disposed at substantially equal intervals from each of the conductive members 11a and 11d1.

  As shown by a straight arrow in FIG. 4B, when the current I to be measured flows through the conducting member 11 from the conducting member 11d1 toward the conducting member 11e1, the measured current I in the conducting member 11a Flows downward from. In the conducting member 11b, the current I to be measured flows from the bottom to the top of the page. That is, in the conducting members 11a and 11b that form adjacent parallel portions, the current I to be measured flows in the opposite direction.

  Further, in the conducting member 11c, the current I to be measured flows from the right to the left of the page. Further, in the conducting member 11e2, the current I to be measured flows from the left to the right of the page. That is, in the conducting members 11c and 11e2 that form adjacent parallel portions, the measured current I flows in the opposite direction. Then, magnetic fields Ba to Bc and 11e2 based on the current I to be measured are generated around the conducting members 11a to 11c and 11e2. At this time, each of the magnetic fields B to Bc and Be2 from the four directions passes through the vertical Hall element 12.

  Since the magnetic fields Ba to Bc and Be2 have directions directed from the front surface to the back surface of the paper in the portions surrounded by the conducting members 11a to 11c and 11e2, the vertical Hall element 12 has the magnetic fields Ba to Bc. , Be2 is output to an external device (not shown) corresponding to the magnetic field B.

  Subsequently, in the conducting members 11a and 11d1 that form adjacent parallel portions, the current I to be measured flows through the conducting members 11a and 11d1 in the opposite direction. Further, in the conductive member 11d2 forming the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba, Bd1, and Bd2 based on the current I to be measured are generated around the conducting members 11a, 11d1, and 11d2. At this time, each of the magnetic fields Ba, Bd1, and Bd2 from the three directions passes through the vertical Hall element 13.

  Since the magnetic fields Ba, Bd1, and Bd2 have directionality from the back surface to the front surface of the paper surface between the conducting members 11a and 11d1, as a result, the vertical Hall element 13 has the magnetic fields Ba, An electric signal corresponding to the magnetic field B ′ obtained by adding Bd1 and Bd2 is output to an external device (not shown).

  By the way, the magnetic field B is a magnetic field having a directivity from the front surface to the back surface in the portion surrounded by the conducting members 11a to 11c and 11e2. The magnetic field B 'is a magnetic field having a direction from the back surface to the front surface between the conducting members 11a and 11d1. In other words, the magnetic field B and the magnetic field B 'have opposite directions.

  For example, even if the magnetic fields B and B ′ are affected by noise such as static electricity, and the electrical signals output from the vertical Hall elements 12 and 13 are affected by the noises according to the magnetic fields B and B ′, respectively. If an averaging operation is performed on the electrical signal, the influence of noise on the electrical signal can be reduced.

  Therefore, according to the current sensor 40 in the present embodiment, it is possible to remove the influence of external noise such as a magnetic field and geomagnetism generated by a peripheral device, and it is possible to realize a coreless current sensor that is hardly affected by noise.

(Fifth embodiment)
A current sensor 50 according to a fifth embodiment of the present invention will be described with reference to FIGS. FIG. 5A is a schematic perspective view of the current sensor 50, and FIG. 5B is a schematic cross-sectional view taken along the ho-ho line of the schematic perspective view.

  As shown in FIG. 5A, the current sensor 50 in the present embodiment is configured to include a conductive member 11 and two magnetoelectric conversion elements 12 and 13. Hereinafter, each part of the conductive member 11 will be described with reference numerals 11a to 11c, 11d1, and 11d2.

  As shown in FIG. 5B, the conductive member 11 has adjacent parallel portions formed continuously. That is, an adjacent parallel portion formed by the conductive members 11a and 11b and an adjacent parallel portion formed by the conductive members 11a and 11d1 are provided. A vertical Hall element 12 as a magnetoelectric conversion element is disposed in a portion surrounded by the conducting members 11a to 11c and 11e2. The vertical Hall element 12 is disposed at substantially equal intervals from each of the conductive members 11a and 11b. In addition, a vertical Hall element 13 as a magnetoelectric conversion element is disposed between the conductive members 11a and 11d1 that form adjacent parallel portions. The vertical Hall element 13 is disposed at substantially equal intervals from each of the conductive members 11a and 11d1.

  As shown by a straight arrow in FIG. 5B, when the current I to be measured flows through the conducting member 11 from the conducting member 11d1 toward the conducting member 11b, the measured current I in the conducting member 11a Flows downward from. In the conducting member 11b, the current I to be measured flows from the bottom to the top of the page.

  That is, in the conducting members 11a and 11b that form adjacent parallel portions, the current I to be measured flows in the opposite direction. In the conducting member 11c forming the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba to Bc based on the current I to be measured are generated around the conducting members 11a to 11c. At this time, each of the magnetic fields Ba to Bc from the three directions passes through the vertical Hall element 12.

  Since the magnetic fields Ba to Bc have a directivity from the front surface to the back surface of the paper between the conducting members 11a and 11b, the vertical Hall element 12 as a result adds up the magnetic fields Ba to Bc. An electric signal corresponding to a magnetic field B having a direction from the front surface to the back surface of the paper is output to an external device (not shown).

  Subsequently, in the conducting member 11a, the measured current I flows from the top to the bottom of the page. In the conducting member 11d1, the current I to be measured flows from the bottom to the top of the page. That is, in the conducting members 11a and 11d1 that form adjacent parallel portions, the current I to be measured flows in the opposite direction. Further, in the conductive member 11d2 forming the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba, Bd1, and Bd2 based on the current I to be measured are generated around the conducting members 11a, 11d1, and 11d2. At this time, each of the magnetic fields Ba, Bd1, and Bd2 from the three directions passes through the vertical Hall element 13.

  Since the magnetic fields Ba, Bd1, and Bd2 have directionality from the back surface to the front surface of the paper surface between the conducting members 11a and 11d1, as a result, the vertical Hall element 13 has the magnetic fields Ba, An electric signal corresponding to a magnetic field B ′ having a directivity from the rear surface to the front surface of Bd1 and Bd2 is output to an external device (not shown).

  By the way, as described above, the magnetic field B and the magnetic field B 'have opposite directions. For example, even if the magnetic fields B and B ′ are affected by noise such as static electricity, and the electrical signals output from the vertical Hall elements 12 and 13 are affected by the noises according to the magnetic fields B and B ′, respectively. If the averaging operation is performed on the electrical signal by an external device (not shown), the influence of noise on the electrical signal can be reduced.

  Therefore, according to the current sensor 50 in the present embodiment, it is possible to reduce the influence of external noise such as a magnetic field and geomagnetism generated by a peripheral device, and it is possible to realize a coreless current sensor that is hardly affected by noise. .

  As shown in FIG. 5B, the current sensor 50 in the present embodiment is arranged in a relatively narrow space because the occupied volume is reduced by making the cross-sectional shape of the conducting member 11 substantially S-shaped. can do.

(Sixth embodiment)
A current sensor 60 according to a sixth embodiment of the present invention will be described with reference to FIGS. 6A is a schematic perspective view of the current sensor 60, and FIG. 6B is a schematic cross-sectional view taken along the line hae of the schematic perspective view.

  As shown in FIG. 6A, the current sensor 60 in the present embodiment includes a conductive member 11 and two magnetoelectric conversion elements 12 and 13. Hereinafter, each part of the conductive member 11 will be described with reference numerals 11a to 11c, 11d1, and 11d2.

  As shown in FIG. 6B, the conducting member 11 is arranged in a substantially rectangular shape so that two sets of adjacent parallel portions are formed. That is, an adjacent parallel portion formed by the conductive members 11a1 and 11b1 and an adjacent parallel portion formed by the conductive members 11a2 and 11b2 are provided. A vertical Hall element 12 as a magnetoelectric conversion element is disposed between the conducting members 11a1 and 11b1. The vertical Hall element 12 is disposed at substantially equal intervals from each of the conductive members 11a1 and 11b1. A vertical Hall element 13 as a magnetoelectric conversion element is disposed between the conductive members 11a2 and 11b2. The vertical Hall element 13 is disposed at substantially equal intervals from each of the conductive members 11a2 and 11b2.

  As shown by a straight arrow in FIG. 6B, when the current I to be measured flows through the conducting member 11 from the conducting member 11d1 toward the conducting member 11e1, the measured current I in the conducting member 11a1 Flows downward from. In the conducting member 11b1, the current I to be measured flows from the bottom to the top of the page. That is, in the conducting members 11a1 and 11b1 that form adjacent parallel portions, the current I to be measured flows in the opposite direction. In the conducting member 11c1 that forms the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba1, Bb1, and Bc1 based on the current I to be measured are generated around the conductive members 11a1, 11b1, and 11c1. At this time, each of the magnetic fields Ba1, Bb1, and Bc1 from the three directions passes through the vertical Hall element 12.

  Since the magnetic fields Ba1, Bb1, and Bc1 each have a direction from the front surface to the back surface of the paper between the conducting members 11a1 and 11b1, the vertical Hall element 12 has the magnetic fields Ba1, Bb1, and Bc1 as a result. The electric signal corresponding to the magnetic field B having the directivity from the front surface to the back surface of the paper is output to an external device (not shown).

  Subsequently, in the conducting member 11a2, the measured current I flows from the top to the bottom of the page. In the conducting member 11b2, the measured current I flows from the bottom to the top of the page. That is, in the conducting members 11a2 and 11b2 that form adjacent parallel portions, the current I to be measured flows in the opposite direction. Further, in the conducting member 11c2 forming the bent portion, the current I to be measured flows from the left to the right toward the paper surface. At this time, each of the magnetic fields Ba2, Bb2, and Bc2 from the three directions passes through the vertical Hall element 13.

  Since the magnetic fields Ba2, Bb2, and Bc2 each have a direction from the front surface to the back surface of the paper between the conducting members 11a2 and 11b2, as a result, the vertical Hall element 12 has the magnetic fields Ba2, Bb2, and Bc2. Is output to an external device (not shown) corresponding to a magnetic field B ′ having a direction from the front surface to the back surface.

  Therefore, according to the current sensor 60 in the present embodiment, the current value of the current I to be measured based on the magnetic field generated around the conducting member forming the adjacent parallel portion without arranging the core for focusing the magnetic field. A coreless current sensor that can measure current can be realized. By the way, according to the current sensor 60 in the present embodiment, the two vertical Hall elements 12 and 13 that detect the magnetic fields B and B ′ in the same direction are arranged. Even so, the function of the other vertical Hall element can be supplemented.

(Seventh embodiment)
A current sensor 70 according to a seventh embodiment of the present invention will be described with reference to FIGS. 7A is a schematic perspective view of the current sensor 70, FIG. 7B is a schematic side view of the current sensor 70 viewed from the direction G, and FIG. 7C is a schematic front view of the current sensor 70 viewed from the direction H. FIG.

  As shown in FIG. 7A, the current sensor 70 in the present embodiment includes a conductive member 11 and two magnetoelectric conversion elements 12 and 13. Hereinafter, each part of the conducting member 11 will be described with reference numerals 11a to 11g.

  As shown in FIG. 7B, the conductive member 11 has two sets of adjacent parallel portions. That is, an adjacent parallel portion formed by the conductive members 11a and 11c and an adjacent parallel portion formed by the conductive members 11d and 11f are provided. A vertical Hall element 12 as a magnetoelectric conversion element is disposed between the conducting members 11a and 11c. The vertical Hall element 12 is disposed at substantially equal intervals from each of the conductive members 11a and 11c. Further, a vertical Hall element 13 as a magnetoelectric conversion element is disposed between the conducting members 11d and 11f. The vertical Hall element 13 is arranged at substantially equal intervals from each of the conductive members 11d and 11f. The distance between the conductive members 11a and 11c forming the adjacent parallel part and the distance between the conductive members 11d and 11f forming the adjacent parallel part are both the distance D.

  As shown by a straight arrow in FIG. 7B, when the measured current I flows from the conducting member 11a to the conducting member 11f through the conducting member 11g, the measured current is measured in the conducting member 11a. I flows from the top to the bottom of the page. In the conducting member 11c, the measured current I flows from the bottom to the top of the page. That is, in the conducting members 11a and 11c that form adjacent parallel portions, the current I to be measured flows in the opposite direction. In the conducting member 11b that forms the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba to Bc based on the current I to be measured are generated around the conducting members 11a to 11c. At this time, each of the magnetic fields Ba to Bc from the three directions passes through the vertical Hall element 12.

  Since the magnetic fields Ba to Bc have directivity from the back surface to the front surface of the paper between the conducting members 11a and 11c, the vertical Hall element 12 as a result adds up the magnetic fields Ba to Bc. An electric signal corresponding to a magnetic field B having a direction from the back surface to the front surface of the paper is output to an external device (not shown).

  Subsequently, in the conductive member 11d, the measured current I flows from the top to the bottom of the page. In the conducting member 11f, the current I to be measured flows from the bottom to the top of the page. That is, the current I to be measured flows in the opposite direction in the conductive members 11d and 11f forming the adjacent parallel portions. Further, in the conducting member 11e forming the bent portion, the current I to be measured flows from the left to the right toward the paper surface. Then, magnetic fields Bd to Bf based on the current I to be measured are generated around the conductive members 11 d to 11 f, and each of these magnetic fields Bd to Bf passes through the vertical Hall element 13.

  Since the magnetic fields Bd to Bf have directionality from the back surface to the front surface between the conductive members 11d and 11f, as a result, the vertical Hall element 13 generates the magnetic fields Bd to Bf from three directions. The summed electric signal corresponding to the magnetic field B ′ having a direction from the back surface to the front surface is output to an external device (not shown).

  Therefore, according to the current sensor 70 in the present embodiment, the current value of the current I to be measured based on the magnetic field generated around the conducting member forming the adjacent parallel portion without arranging the core for focusing the magnetic field. A coreless current sensor that can measure current can be realized. By the way, according to the current sensor 70 in the present embodiment, the two vertical Hall elements 12 and 13 that detect the magnetic fields B and B ′ in the same direction are arranged. Even so, the function of the other vertical Hall element can be supplemented.

(Eighth embodiment)
A current sensor 80 according to a seventh embodiment of the present invention will be described with reference to FIGS. FIG. 8A is a schematic perspective view of the current sensor 80, FIG. 8B is a schematic side view of the current sensor 80 viewed from the H direction, and FIG. 8C is a schematic front view of the current sensor 80 viewed from the reverse direction. FIG.

  As shown in FIG. 8A, the current sensor 80 in the present embodiment includes a conductive member 11 and two magnetoelectric conversion elements 12 and 13. Hereinafter, each part of the conducting member 11 will be described with reference numerals 11a to 11g.

  As shown in FIG. 8B, the conductive member 11 has two sets of adjacent parallel portions formed continuously. That is, an adjacent parallel portion formed by the conductive members 11a and 11c and an adjacent parallel portion formed by the conductive members 11d and 11f are provided. A vertical Hall element 12 as a magnetoelectric conversion element is disposed between the conducting members 11a and 11c. The vertical Hall element 12 is disposed at substantially equal intervals from each of the conductive members 11a and 11c. Further, a vertical Hall element 13 as a magnetoelectric conversion element is disposed between the conducting members 11d and 11f. The vertical Hall element 13 is arranged at substantially equal intervals from each of the conductive members 11d and 11f. The distance between the conductive members 11a and 11c forming the adjacent parallel part and the distance between the conductive members 11d and 11f forming the adjacent parallel part are both the distance D.

  As shown by a straight arrow in FIG. 8B, when the current I to be measured flows through the conducting member 11 from the conducting member 11a toward the conducting member 11f through the conducting member 11g, the current to be measured is measured in the conducting member 11a. I flows from the top to the bottom of the page. In the conducting member 11c, the measured current I flows from the bottom to the top of the page.

  That is, in the conducting members 11a and 11c that form adjacent parallel portions, the current I to be measured flows in the opposite direction. In the conducting member 11b that forms the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Ba to Bc based on the current I to be measured are generated around the conducting members 11a to 11c. At this time, each of the magnetic fields Ba to Bc from the three directions passes through the vertical Hall element 12.

  Since the magnetic fields Ba to Bc have directivity from the back surface to the front surface of the paper between the conducting members 11a and 11c, the vertical Hall element 12 as a result adds up the magnetic fields Ba to Bc. An electric signal corresponding to a magnetic field B having a direction from the back surface to the front surface of the paper is output to an external device (not shown).

  Subsequently, in the conductive member 11d, the measured current I flows from the top to the bottom of the page. In the conducting member 11f, the current I to be measured flows from the bottom to the top of the page. That is, the current I to be measured flows in the opposite direction in the conductive members 11d and 11f forming the adjacent parallel portions. In the conducting member 11e that forms the bent portion, the current I to be measured flows from right to left toward the paper surface. Then, magnetic fields Bd to Bf based on the current I to be measured are generated around the conductive members 11 d to 11 f, and each of these magnetic fields Bd to Bf passes through the vertical Hall element 13.

  Since the magnetic fields Bd to Bf have directionality from the front surface to the back surface between the conducting members 11d and 11f, as a result, the vertical Hall element 13 generates the magnetic fields Bd to Bf from three directions. The summed electric signal corresponding to the magnetic field B ′ having a direction from the front surface to the back surface is output to an external device (not shown).

  By the way, as described above, the magnetic field B and the magnetic field B 'have opposite directions. For example, even if the magnetic fields B and B ′ are affected by noise such as static electricity, and the electrical signals output from the vertical Hall elements 12 and 13 are affected by the noises according to the magnetic fields B and B ′, respectively. If the averaging operation is performed on the electrical signal by an external device (not shown), the influence of noise on the electrical signal can be reduced.

  Therefore, according to the current sensor 80 in the present embodiment, it is possible to reduce the influence of external noise such as a magnetic field or geomagnetism generated by a peripheral device, and it is possible to realize a coreless current sensor that is hardly affected by noise. .

(Other embodiments)
A current sensor 90 according to another embodiment of the present invention will be described with reference to FIGS. FIG. 9A is a schematic perspective view of the current sensor 90, and FIG. 9B is a schematic cross-sectional view taken along a Nuun line in the schematic perspective view.

  As shown in FIG. 9A, the current sensor 90 in the present embodiment is composed of a nonmagnetic metal such as copper or aluminum between the conductive members 11a and 11b forming adjacent parallel portions. The shield material 14 is disposed so as to cover the vertical Hall element 12 as a magnetoelectric conversion element. By using a non-magnetic metal as a shielding material, the magnetoelectric conversion element 12 can be protected from electrical noise such as static electricity without weakening the magnetic field passing through the vertical Hall element 12. The shield effect is improved by grounding the shield material 14.

  10A is a top view when the magnetic flux collecting plate 15 is disposed on one surface side of the vertical Hall element 12 while avoiding the sensor portion 12s, and FIG. 10B is a sensor portion on one surface side of the vertical Hall element 12. FIG. It is sectional drawing at the time of arrange | positioning the magnetism collecting plate 15 avoiding 12s.

  The sensitivity of the vertical Hall element 12 can be improved by disposing the magnetism collecting plate 15 on one surface side of the vertical Hall element 12 while avoiding the sensor portion 12s. Therefore, in the coreless current sensor of the present invention, the vertical Hall element 12 on which the magnetic flux collecting plate 15 is arranged is suitable.

  Although the best mode for carrying out the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. is there. In the invention according to the dependent claims of the present invention, a part of the constituent features of the dependent claims can be omitted.

It is a figure which shows the current sensor in the 1st Embodiment of this invention. It is a figure which shows the current sensor in the 2nd Embodiment of this invention. It is a figure which shows the current sensor in the 3rd Embodiment of this invention. It is a figure which shows the current sensor in the 4th Embodiment of this invention. It is a figure which shows the current sensor in the 5th Embodiment of this invention. It is a figure which shows the current sensor in the 6th Embodiment of this invention. It is a figure which shows the current sensor in the 7th Embodiment of this invention. It is a figure which shows the current sensor in the 8th Embodiment of this invention. It is a figure which shows the current sensor in other embodiment of this invention. It is the figure which has arrange | positioned the magnetic flux collecting board on the one surface side of the magnetoelectric conversion element. It is a figure explaining operation | movement of a vertical Hall element. It is a figure which shows the conventional current sensor.

Explanation of symbols

10, 20, 30, 40, 50, 60, 70, 80, 90, 100 ... current sensor, 11, 54 ... conductive member, 12, 13, 52 ... magnetoelectric transducer, 12s ... Sensor part, 14 ... Shield material, 15 ... Magnetic collecting plate, 51 ... Core, 53 ... Gap

Claims (13)

A conducting member formed with adjacent parallel portions in which the current to be measured flows in the opposite direction;
An electric signal corresponding to the magnetic field is detected by detecting a magnetic field generated around the conducting member when the current to be measured flows through the conducting member. A current sensor comprising: an output magnetoelectric conversion element. The conducting member is composed of a flat plate,
The current sensor according to claim 1, wherein the adjacent parallel portion is formed by bending the flat plate. The conducting member is composed of a plurality of conductor pieces,
The adjacent parallel portion is formed of first and second conductor pieces arranged to face each other so as to be substantially parallel,
The first and second conductor pieces are connected via a third conductor piece connected to one end of each of the first and second conductor pieces. Current sensor.   The current sensor according to claim 1, wherein the magnetoelectric conversion element is narrower than the conducting member and is disposed so as to be within the width of the conducting member.   5. The current sensor according to claim 1, wherein the magnetoelectric conversion elements are arranged at substantially equal intervals from each of the conducting members forming the adjacent parallel portion. The conductive member is arranged so as to constitute each side of the rectangle, and two sets of the adjacent parallel portions are formed,
The current sensor according to claim 1, wherein the magnetoelectric conversion element is disposed in the rectangle. The conducting member includes a plurality of the adjacent parallel portions,
The current sensor according to claim 1, wherein the magnetoelectric conversion elements are respectively disposed between the conducting members that form the plurality of adjacent parallel portions.   The current sensor according to claim 1, wherein a magnetic current collecting plate made of a magnetic material is disposed on one surface side of the magnetoelectric conversion element.   The current sensor according to claim 8, wherein the magnetism collecting plate is disposed avoiding a sensor portion of the magnetoelectric conversion element. With a shielding material made of non-magnetic metal that shields noise from the outside,
The current sensor according to claim 1, wherein the shield material is disposed between the conductive members that form the adjacent parallel portions so as to cover the magnetoelectric conversion element.   The current sensor according to claim 10, wherein the shield material is grounded.   The current sensor according to claim 1, wherein the magnetoelectric conversion element is a vertical Hall element.   The current sensor according to claim 1, wherein the magnetoelectric conversion element is a magnetoresistive element.

Images