JP5542466B2 - Magnetic sensor device - Google Patents

Description

  The present invention relates to a magnetic sensor device for detecting magnetic characteristics of a medium such as an object to which a magnetic material is attached or a banknote printed with magnetic ink.

  When detecting magnetic properties of an object such as a card to which a magnetic material is attached or a banknote printed with magnetic ink, a magnetic sensor device is provided in the middle of the conveyance path of the medium. The sensor device includes a magnetic sensor element (see Patent Document 1).

  In the magnetic sensor device described in Patent Document 1, the magnetic sensor element has a structure in which coils 93 and 94 are wound around a sensor core 91 as shown in FIG. In the sensor core 91, a plurality of protrusions 911 to 916 protrude from the body 910 extending in the width direction W90 of the magnetic sensor element 90 toward the medium moving path 11 side and the opposite side of the medium 1. Among the three protrusions 911 to 913 protruding toward the medium moving path 11 side, the coil 93 is wound around the protrusion 912 positioned at the center in the width direction W90 as an excitation coil. Of the three protrusions 914 to 916 that protrude toward the side opposite to the medium moving path 11 side of the medium 1, the coil 94 is connected to the protrusion 915 located in the center in the width direction W90. It is wound as. Here, the magnetic sensor element 90 is arranged with the width direction W90 facing the moving direction X of the medium 1, and is orthogonal to both the width direction W90 and the height direction V90 from which the protrusions 911 to 916 protrude. The thickness direction T90 faces the medium width direction Y orthogonal to the moving direction X of the medium 1. A plurality of magnetic sensor elements 90 are arranged in the medium width direction Y, and can detect magnetic characteristics from the entire medium 1 as the medium 1 moves.

JP 2007-241653 A

  However, in the magnetic sensor element 90 described in Patent Document 1, a change in magnetic flux generated between the protrusions 911 and 913 located at both ends in the width direction W90 (both ends in the moving direction X of the medium 1) is generated in the width direction W90. In the sensitivity distribution in the thickness direction T90 (medium width direction Y orthogonal to the moving direction X of the medium 1), detection is performed by the coils 93 and 94 wound around the protrusions 912 and 915 located at the center. As shown in (b), although it is high in the region where the sensor core 91 is present, the sensitivity is drastically lowered even if it is slightly shifted from the magnetic sensor element 90 in the thickness direction T90 (medium width direction Y). For this reason, if a plurality of magnetic sensor elements 90 are arranged in the medium width direction Y perpendicular to the moving direction X of the medium 1, the sensitivity is drastically lowered in the region sandwiched between the two magnetic sensor elements 90. Therefore, when the width of the magnetic region 1a attached to the medium 1 is narrow, if the medium 1 is shifted in the medium width direction Y and passes between the magnetic sensor elements 90, the magnetic characteristics of the medium 1 cannot be detected. There is.

  In view of the above problems, an object of the present invention is to provide a magnetic sensor device capable of expanding the detection range in the medium width direction orthogonal to the moving direction of the medium in the magnetic sensor device.

In order to solve the above-described problems, the present invention provides a magnetic sensor device including a magnetic sensor element that detects a magnetic characteristic of a relatively moving medium, and the magnetic sensor element extends in a width direction of the magnetic sensor element. A sensor core provided with three or more odd number of magnetic flux collecting protrusions protruding toward the medium moving path side of the medium from the existing body and spaced apart from each other in the width direction; together comprising an exciting coil wound around each of the current even portion sandwiched by magnetizing projection adjacent, and a detection coil wound around each of the plurality of current magnetizing projection, the width The thickness direction orthogonal to both the direction and the projecting direction of the magnetic flux collecting projections is arranged in a direction intersecting with the medium moving direction so that the thickness direction is directed to the medium moving direction. cage, the width direction of the sensor core Law, the is greater than the dimension in the thickness direction, said the magnetic sensor element, the exciting coil adjacent in the width direction are wound in opposite directions, the exciting coil between the magnetic sensor element adjacent The winding direction of is reverse .

  In the present invention, in the sensor core of the magnetic sensor element, a plurality of magnetic flux collecting projections protruding from the body portion extending in the width direction toward the medium moving path side of the medium are separated from each other in the width direction. A detection coil is wound around the plurality of magnetic flux collecting projections, and an excitation coil is wound around the body portion. For this reason, when the exciting coil is energized, a magnetic flux is formed around the magnetic flux collecting projection, so if a change in the magnetic flux is detected through the detection coil wound around the magnetic flux collecting projection, Magnetic characteristics such as magnetic permeability can be detected. Here, the magnetic sensor element is arranged so that the thickness direction is directed to the moving direction of the medium, and the magnetic flux collecting projection and the detection coil are separated in the medium width direction orthogonal to the moving direction of the medium. In the position. For this reason, the magnetic sensor element has substantially the same sensitivity from the region where the sensor core exists and the position where the sensor core exists to the position shifted in the width direction (medium width direction orthogonal to the moving direction of the medium) The detection range in the medium width direction perpendicular to the moving direction of the medium is wide.

  In the present invention, since the dimension in the width direction of the sensor core is larger than the dimension in the thickness direction, it is more effective. According to the present invention, since the width direction of the sensor core is the medium width direction perpendicular to the moving direction of the medium, the medium width orthogonal to the moving direction of the medium even if the dimension in the thickness direction of the sensor core is reduced. Wide detection range in direction.

  Furthermore, in the present invention, a plurality of the magnetic sensor elements are arranged in a direction crossing the moving direction of the medium. Accordingly, since a plurality of magnetic flux collecting protrusions and detection coils are arranged in the medium width direction, the same sensitivity can be realized over the entire medium width direction.

In the present invention, the exciting coil is wound around a portion sandwiched between the two magnetic flux collecting protrusions adjacent in the width direction. Therefore, a magnetic flux can be formed between two magnetism-collecting projections that are adjacent in the width direction, regardless of the number of magnetism-collecting projections.

In the present invention, it is preferable that the detection coils wound around each of the plurality of protrusions are electrically connected in series. If comprised in this way, since the output by which the detection result in the detection coil wound around each of the some magnetic flux collection protrusions was totaled can be obtained, a sensitivity can be improved.

In the present invention, among the three or more odd number of magnetic flux collection protrusions, the detection coil wound around the magnetic flux collection protrusions located at both ends in the width direction is another magnetic flux collection protrusion. It is preferable that the number of windings is larger than that of the detection coil wound around. If comprised in this way, since the sensitivity in a part with low magnetic flux density, such as the both ends of the width direction, can be improved, the detection sensitivity in the width direction of a magnetic sensor element can be made equivalent.

In this case, it is preferable that among the three or more odd number of the magnetic flux collecting protrusions, the magnetic flux collecting protrusions positioned at both ends in the width direction are thinner than the other magnetic flux collecting protrusions. With this configuration, the number of turns of the detection coil wound around the magnetic flux collection protrusions located at both ends in the width direction is larger than that of the detection coil wound around the other magnetic flux collection protrusions. Can do a lot.

  In the present invention, it is preferable that the sensor core includes a protrusion that protrudes from the body portion to the opposite side of the magnetic flux collection protrusion. If comprised in this way, magnetic resistance when it sees from an exciting coil can be reduced. Therefore, since the magnetic flux generated when the same current is passed can be increased, the sensitivity can be improved. In addition, when the fluxgate method for saturating the sensor core is adopted, the drive current is reduced, so that current consumption and heat generation can be reduced. Further, if the differential coil is wound around the protrusion, the magnetic characteristic of the medium can be detected using the difference between the detection result of the detection coil and the detection result of the differential coil. Therefore, disturbances such as temperature changes can be compensated.

  In the present invention, the sensor core may be configured to include an amorphous magnetic material layer and a nonmagnetic substrate that sandwiches the amorphous magnetic material layer on both sides. If such a sensor core is used, a thin sensor core can be provided, so that the resolution in the moving direction of the medium can be improved.

  In the present invention, in the sensor core of the magnetic sensor element, a plurality of magnetic flux collecting projections protruding from the body portion extending in the width direction toward the medium moving path side of the medium are separated from each other in the width direction. A detection coil is wound around the plurality of magnetic flux collecting projections, and an excitation coil is wound around the body portion. For this reason, when the exciting coil is energized, a magnetic flux is formed around the magnetic flux collecting projection, so if a change in the magnetic flux is detected through the detection coil wound around the magnetic flux collecting projection, Magnetic characteristics such as magnetic permeability can be detected. Here, the magnetic sensor element is arranged so that the thickness direction is directed to the moving direction of the medium, and the magnetic flux collecting projection and the detection coil are separated in the medium width direction orthogonal to the moving direction of the medium. In the position. Therefore, the magnetic sensor element has substantially the same sensitivity even in a position shifted in the width direction (medium width direction orthogonal to the medium movement direction) from the region where the sensor core exists, and is orthogonal to the medium movement direction. The detection range in the medium width direction is wide.

It is explanatory drawing which shows the structure of the magnetic pattern detection apparatus provided with the magnetic sensor apparatus of the basic structural example . It is explanatory drawing of the magnetic sensor apparatus of a basic structural example . It is explanatory drawing of the magnetic sensor element used for the magnetic sensor apparatus of the example of basic composition . It is explanatory drawing which shows the structural example of the sensor core used for the magnetic sensor element of the magnetic sensor apparatus of a basic structural example . It is a block diagram which shows the structure of the signal processing system of the magnetic sensor apparatus of a basic structural example . It is explanatory drawing which shows the characteristic etc. of various magnetic inks formed in the medium from which magnetism is detected in the magnetic sensor apparatus of a basic structural example . It is explanatory drawing which shows the principle which detects the presence or absence of a magnetic pattern from the medium in which the magnetic pattern from which a kind differs was formed in the magnetic pattern detection apparatus of a basic structural example . It is explanatory drawing which shows the result of having detected the magnetic pattern from the medium from which a kind differs using the magnetic pattern detection apparatus of the example of a basic composition . It is explanatory drawing of the magnetic sensor element used for the magnetic sensor apparatus which concerns on embodiment to which this invention is applied . It is explanatory drawing of the magnetic sensor element used for the magnetic sensor apparatus which concerns on another embodiment to which this invention is applied . It is explanatory drawing of the conventional magnetic sensor apparatus.

  Embodiments of the present invention will be described with reference to the drawings. In the present invention, in the magnetic sensor element 40, the direction in which the body portion 42 of the sensor core 41 extends and the direction in which the magnetic flux collecting projection 43 is spaced apart are defined as the width direction W40 of the magnetic sensor element 40 and sensor core 41. And the direction in which the magnetic flux collecting projection 43 protrudes is the height direction V40 of the magnetic sensor element 40 and sensor core 41, and the direction perpendicular to both the width direction W40 and the height direction V40 is the magnetic sensor element 40 and The thickness direction T40 of the sensor core 41 is set. Of the two directions orthogonal to the moving direction X of the medium 1, the width direction of the medium 1 is set as a medium width direction Y orthogonal to the moving direction X of the medium 1.

(overall structure)
FIG. 1 is an explanatory diagram showing a configuration of a magnetic pattern detection device including a magnetic sensor device of a basic configuration example , and FIGS. 1A and 1B schematically show a main configuration of the magnetic pattern detection device. It is explanatory drawing which shows, and explanatory drawing which shows a cross-sectional structure typically.

  A magnetic pattern detection device 100 shown in FIG. 1 is a device that detects magnetism from a medium 1 such as a banknote or a securities, and performs authenticity determination or type determination. A sheet is detected by a roller or a guide (not shown). And a magnetic sensor device 20 that detects magnetism from the medium 1 at an intermediate position of the medium moving path 11 by the conveying device 10. In this embodiment, the roller and the guide are made of a nonmagnetic material such as aluminum. In this embodiment, the magnetic sensor device 20 is disposed below the medium movement path 11, but may be disposed above the medium movement path 11. In any case, the magnetic sensor device 20 is arranged so that the sensor surface 21 faces the medium moving path 11.

  In this embodiment, the medium 1 is provided with a magnetic pattern with magnetic ink on a narrow magnetic region 1a extending in the moving direction X of the medium 1. The magnetic pattern has a residual magnetic flux density Br and a permeability μ. Are formed of a plurality of types of magnetic inks. For example, the medium 1 is formed with a first magnetic pattern printed with magnetic ink containing hard material and a second magnetic pattern printed with magnetic ink containing soft material. Therefore, the magnetic pattern detection apparatus 100 of the present embodiment detects the presence / absence of each magnetic pattern in the medium 1 based on both the residual magnetic flux density level and the magnetic permeability level. In this embodiment, the magnetic sensor device 20 for detecting such two types of magnetic patterns is common. Therefore, the magnetic pattern detection apparatus 100 of this embodiment has the following configuration. The hard material is a magnetic material that is easily magnetized when applied with a magnetic field from the outside, such as a magnetic material used in a magnet, having a large hysteresis and a high residual magnetic flux density. On the other hand, the soft material is a magnetic material that has a small hysteresis, a low residual magnetic flux density, and is not easily magnetized, like a core material of a motor or a magnetic head.

(Configuration of Magnetic Sensor Device 20)
FIG. 2 is an explanatory diagram of the magnetic sensor device 20 of the basic configuration example , and FIGS. 2A, 2B, and 2C are explanatory diagrams showing a layout of magnetic sensor elements and the like in the magnetic sensor device 20, and magnetic It is explanatory drawing which shows direction of a sensor element, and explanatory drawing which shows the sensitivity distribution in the medium width direction Y orthogonal to the moving direction X of the medium 1 at the time of arranging two magnetic sensor elements in the width direction.

  As shown in FIGS. 1 and 2A, in the magnetic pattern detection device 100 of the present embodiment, the magnetic sensor device 20 includes a magnetic field applying magnet 30 that applies a magnetic field to the medium 1, and a medium after the magnetic field is applied. 1 includes a magnetic sensor element 40 that detects a magnetic flux when a bias magnetic field is applied, and a nonmagnetic case 25 that covers the magnetic field applying magnet 30 and the magnetic sensor element 40. The magnetic sensor device 20 includes a sensor surface 21 that is substantially flush with the medium movement path 11, and slope portions 22 and 23 that are connected to both sides of the sensor surface 21 in the movement direction of the medium 1. The shape is defined by the shape of the case 25. In this embodiment, since the slope portions 22 and 23 are provided, there is an advantage that the medium 1 is not easily caught.

  The magnetic sensor device 20 extends in a direction crossing the moving direction X of the medium 1, and a plurality of magnetic field applying magnets 30 and magnetic sensor elements 40 are arranged in a direction crossing the moving direction X of the medium 1. ing. In this embodiment, the magnetic sensor device 20 extends in the medium width direction Y orthogonal to the movement direction X among the directions intersecting the movement direction X of the medium 1, and the magnetic field applying magnet 30 and the magnetic sensor element 40. Are arranged in the medium width direction Y orthogonal to the movement direction X.

  In the present embodiment, the magnetic field application magnet 30 is arranged as a first magnetic field application magnet 31 and a second magnetic field application magnet 32 on both sides in the moving direction of the medium 1 with respect to the magnetic sensor element 40, and is indicated by an arrow X1. A magnetic field applying first magnet 31, a magnetic sensor element 40, and a magnetic field applying second magnet 32 are arranged in this order along the moving direction of the medium 1 shown. A magnetic field application second magnet 32, a magnetic sensor element 40, and a magnetic field application first magnet 31 are arranged in this order along the moving direction of the medium 1 indicated by the arrow X2, and the medium 1 is indicated by the arrow X1. The magnetic property of the medium 1 can be detected regardless of the direction and the direction indicated by the arrow X2. Here, the magnetic sensor element 40 is disposed at an intermediate position between the first magnetic field application magnet 31 and the second magnetic field application magnet 32, and is separated from the magnetic sensor element 40 from the first magnetic field application magnet 31. The distance is equal to the separation distance between the magnetic field application second magnet 32 and the magnetic sensor element 40. The first magnetic field application magnet 31, the magnetic sensor element 40, and the second magnetic field application magnet 32 are all arranged so as to face the sensor surface 21 of the magnetic sensor device 20.

  In this embodiment, the magnetic field application magnet 30 (the first magnetic field application magnet 31 and the second magnetic field application magnet 32) includes a permanent magnet 35 such as a ferrite or neodymium magnet. In both the first magnetic field application magnet 31 and the second magnetic field application magnet 32, the permanent magnet 35 has a pole on which the side located on the sensor surface 21 is different from the side opposite to the side on which the sensor surface 21 is located. Magnetized. For this reason, in the permanent magnet 35, a surface located on the sensor surface 21 side functions as a magnetized surface 350 for the medium 1. That is, in the magnetic pattern detection device 100 of the present embodiment, as described later, when the moving medium 1 as indicated by the arrow X1 passes through the magnetic sensor device 20, first, the magnetic field applying first magnet 31 is changed to the medium 1. The medium 1 after being magnetized by the magnetic field passes through the magnetic sensor element 40. Further, when the moving medium 1 passes through the magnetic sensor device 20 as shown by the arrow X2, first, a magnetic field is applied to the medium 1 from the second magnetic field application magnet 32, and the medium is magnetized by the magnetic field. 1 passes through the magnetic sensor element 40.

The plurality of permanent magnets 35 used for the magnetic field applying magnet 30 are all the same in size and shape, but are arranged in the following orientations. First, in both the first magnetic field application magnet 31 and the second magnetic field application magnet 32, the permanent magnets 35 adjacent in the medium width direction Y orthogonal to the moving direction X of the medium 1 are attached in opposite directions. It is magnetized. That is, of the plurality of permanent magnets 35 arranged in the medium width direction Y perpendicular to the moving direction X of the medium 1, one permanent magnet 35 is magnetized with an N pole at the end located on the medium moving path 11 side. The end located on the side opposite to the medium moving path 11 side is magnetized to the S pole, but the permanent magnet is adjacent to the permanent magnet 35 in the direction Y perpendicular to the moving direction X of the medium 1. 35, the end located on the medium moving path 11 side is magnetized to the S pole, and the end located on the opposite side to the medium moving path 11 side is magnetized to the N pole. In this embodiment, the permanent magnet 35 of the first magnetic field application magnet 31 and the permanent magnet 35 of the second magnetic field application magnet 32 that face each other in the moving direction of the medium 1 have different poles across the magnetic sensor element 40. Opposite. However, the permanent magnet 35 of the first magnetic field application magnet 31 and the permanent magnet 35 of the second magnetic field application magnet 32 that face each other in the moving direction of the medium 1 are arranged so that the same poles face each other across the magnetic sensor element 40. Sometimes placed.

(Configuration of the magnetic sensor element 40)
FIG. 3 is an explanatory diagram of the magnetic sensor element 40 used in the magnetic sensor device 20 of the basic configuration example . FIGS. 3A, 3B, and 3C are front views of the magnetic sensor element 40. FIG. 5 is an explanatory diagram of an excitation waveform for the sensor element 40 and an explanatory diagram of an output signal from the magnetic sensor element 40. 3A shows a state where the medium 1 moves in a direction perpendicular to the drawing.

  As shown in FIGS. 1B, 2A, and 2B, the magnetic sensor element 40 is a thin plate, and the size in the width direction W40 is larger than the size in the thickness direction T40. It is. For example, the magnetic sensor element 40 has a dimension in the thickness direction T40 of 5 to 50 [μm] and a dimension in the width direction W40 of 8 to 10 [mm], excluding the nonmagnetic member 46 shown in FIG. The dimension in the height direction V40 is 5 to 15 [mm]. The magnetic sensor element 40 is arranged with the thickness direction T40 facing the moving direction X of the medium 1, and the width direction W40 faces the medium width direction Y orthogonal to the moving direction X of the medium 1.

  The magnetic sensor element 40 is covered with a thin non-magnetic member 46 having a thickness of about 0.3 mm to 1 mm made of ceramic or the like on both sides. The magnetic sensor element 40 may be housed in a magnetic shield case (not shown). In this case, the magnetic shield case is opened at the top where the medium movement path is located, and the magnetic sensor element 40 is exposed from the magnetic shield case toward the medium movement path 11.

  As shown in FIGS. 1B, 2A, 2B, and 3A, the magnetic sensor element 40 includes a sensor core 41, an excitation coil 48 wound around the sensor core 41, and a sensor core. And a detection coil 49 wound around 41. In the present embodiment, the sensor core 41 includes a body part 42 extending in the width direction W40 of the magnetic sensor element 40, and a magnetic flux collecting protrusion 43 that protrudes from the body part 42 toward the medium moving path 11 side of the medium 1. It has. Here, the magnetic flux collecting projections 43 are configured as two magnetic flux collecting projections 431 and 432 protruding from both ends of the body portion 42 in the width direction W40 toward the medium moving path 11 side of the medium 1. The two magnetic flux collecting projections 431 and 432 are separated in the width direction W40. In addition, the sensor core 41 includes a protrusion 44 that protrudes from the body 42 to the side opposite to the magnetism-collecting protrusion 43. In this embodiment, the protrusion 44 has both end portions in the width direction W40 of the body 42. Are formed as two protrusions 441 and 442 protruding toward the opposite side of the medium 1 from the medium moving path 11 side.

With respect to the sensor core 41 configured as described above, the exciting coil 48 is wound around a portion sandwiched between the magnetic flux collecting projections 431 and 432 and the projections 441 and 442 in the trunk portion 42. Further, the detection coil 49 is wound around the magnetic flux collecting projection 43, and in this embodiment, the detection coil 49 includes two magnetic flux collecting projections 43 (the magnetic flux collecting projections 431 and 432) of the sensor core 41. Among them, a detection coil 491 wound around the magnetic flux collection protrusion 431 and a detection coil 492 wound around the magnetic flux collection protrusion 432 are included. Here, the two detection coils 491 and 492 are wound around the magnetic flux collecting projections 431 and 432 in opposite directions. Further, since the two detection coils 491 and 492 are formed by continuously winding one coil wire around the magnetic flux collecting projections 431 and 432, the two detection coils 491 and 492 are electrically connected in series. It is connected to the. The two detection coils 491 and 492 may be wound around the magnetic flux collecting projections 431 and 432, respectively, and then electrically connected in series.

  In the magnetic sensor element 40 configured as described above, the thickness direction T40 perpendicular to both the width direction W40 and the projecting direction (height direction V40) of the magnetic flux collecting projection 43 is directed to the moving direction X of the medium 1. In the magnetic sensor element 40, the width direction W40 in which the magnetic flux collecting protrusions 43 (magnetic flux collecting protrusions 431 and 432) and the detection coils 49 (detection coils 491 and 492) are separated from each other is It faces the medium width direction Y perpendicular to the movement direction X.

  In the magnetic sensor element 40, an alternating current (see FIG. 3B) is applied to the exciting coil 48 at a constant current from an exciting circuit 50 described later with reference to FIG. For this reason, as shown in FIG. 3A, a bias magnetic field is formed around the sensor core 41, and the detection coil 49 outputs a signal having a detection waveform shown in FIG. . Here, the detected waveform shown in FIG. 3C is a differential signal with respect to the bias magnetic field and time.

  A plurality of magnetic sensor elements 40 are arranged in the medium width direction Y. In such a plurality of magnetic sensor elements 40, the winding directions of the excitation coil 48 and the detection coil 49 are the same. For this reason, even when a common exciting current is supplied to the exciting coils 48 of the plurality of magnetic sensor elements 40, the magnetic poles of the magnetic flux collecting projections 43 adjacent to each other between the adjacent magnetic sensor elements 40 are reversed. Therefore, a magnetic flux can be generated between the adjacent magnetic sensor elements 40.

(Configuration example of magnetic sensor element 40)
4A and 4B are explanatory views showing a configuration example of the sensor core 41 used in the magnetic sensor element 40 of the magnetic sensor device 20 of the basic configuration example . FIGS. 4A and 4B are a perspective view and an exploded view of the sensor core 41. FIG. It is a perspective view.

  As shown in FIGS. 4A and 4B, the sensor core 41 of the magnetic sensor element 40 described with reference to FIG. 2B and FIG. The magnetic material layer 41c is sandwiched between the magnetic second substrate 41b. In this embodiment, the magnetic material layer 40c is made of a thin plate-like amorphous metal foil made of an amorphous (amorphous) metal magnetic material bonded to one surface of the first substrate 41a by an adhesive layer (not shown). The second substrate 41b is bonded to one surface of the first substrate 41a by an adhesive layer so as to sandwich the magnetic material layer 41c therebetween. Each of these adhesive layers is a layer formed by solidifying a prepreg formed by impregnating a resin material into a fiber reinforcing material such as glass cloth, carbon fiber, or aramid fiber. As the resin material, an epoxy resin type or a phenol resin type is used. A thermosetting resin such as polyester resin is used. The amorphous metal foil used as the magnetic material layer 41c is formed by rolling with a roll, and examples of cobalt-based materials include Co—Fe—Ni—Mo—B—Si, Co—Fe—Ni—B—Si, and the like. Amorphous alloys, such as Fe-B-Si, Fe-B-Si-C, Fe-B-Si-Cr, Fe-Co-B-Si, Fe-Ni-Mo-B, etc. Can be illustrated.

Here, the first substrate 41 a and the second substrate 41 b have the same shape, and define the outer shape of the sensor core 41. In this embodiment, as the nonmagnetic substrate used for the first substrate 41a and the second substrate 41b, a ceramic substrate such as an alumina substrate, a glass substrate or the like can be exemplified, and a plastic substrate can be used as long as sufficient rigidity can be obtained. May be used. At least one of the first substrate 41a and the second substrate 41b is preferably a light-transmitting substrate so that the magnetic material layer 41c can be confirmed during a process such as cutting. The magnetic material layer 41c is smaller than the first substrate 41a and the second substrate 41b. Therefore, the magnetic material layer 41c is located slightly inside the outer peripheral edges of the first substrate 41a and the second substrate 41b, and the outer peripheral edges of the magnetic material layer 41c (the outer periphery of the first substrate 41a and the second substrate 41b). The periphery) is a sealing part.

  In order to manufacture the sensor core 41 having such a configuration, a magnetic material layer 41c bonded to the first substrate 41a via an adhesive layer is patterned using a photolithographic technique, and then is applied to one surface of the first substrate 41a. Then, the second substrate 41b is joined by the adhesive layer so as to sandwich the magnetic material layer 41c. At that time, a method of using a large substrate as the first substrate 41a, patterning and forming a plurality of magnetic material layers 41c on the large substrate, bonding the large second substrate 41b, and then cutting to a predetermined size. If this is adopted, the sensor core 41 can be manufactured efficiently.

(Configuration of the signal processing unit 60)
FIG. 5 is a block diagram showing the configuration of the signal processing system of the magnetic sensor device 20 of the basic configuration example . In this embodiment, the circuit shown in FIG. 5 includes an excitation circuit 50 that applies the alternating current shown in FIG. 3B to the excitation coil 48, and a signal processing unit 60 that is electrically connected to the detection coil 49. Yes. The signal processing unit 60 extracts the first signal S1 corresponding to the residual magnetic flux density level and the second signal S2 corresponding to the magnetic permeability level from the signal output from the detection coil 49 of the magnetic sensor device 20, and this signal The presence / absence and formation position of a plurality of types of magnetic patterns on the medium 1 are detected based on the extraction results of the above and the relative position information between the medium 1 and the magnetic sensor device 20. More specifically, the signal processing unit 60 includes an amplifier 61 that amplifies the signal output from the magnetic sensor device 20, a peak hold circuit 62 that holds the peak value and the bottom value of the signal output from the amplifier 61, and A bottom hold circuit 63; an addition circuit 64 that adds the peak value and the bottom value to extract the first signal S1, and a subtraction circuit 65 that subtracts the peak value and the bottom value to extract the second signal S2. I have. Further, the signal processing unit 60 relates each signal output from the adding circuit 64 and the subtracting circuit 65 to the relative position information between the magnetic sensor device 20 and the medium 1, and compares the comparison pattern recorded in advance in the recording unit 661. And a determination unit 66 that determines whether the medium 1 is true or false. The determination unit 66 is configured by a microcomputer or the like, and performs predetermined processing based on a program recorded in advance in a recording unit (not shown) such as a ROM or a RAM to determine whether the medium 1 is true or false. To do.

(Detection principle)
FIG. 6 is an explanatory diagram showing characteristics and the like of various magnetic inks formed on the medium 1 in which magnetism is detected in the magnetic sensor device 20 of the basic configuration example . FIG. 7 is an explanatory diagram showing the principle of detecting the presence or absence of a magnetic pattern from the medium 1 on which different types of magnetic patterns are formed in the magnetic pattern detection device 100 of the basic configuration example .

  First, the principle of determining the authenticity of the medium 1 when the medium 1 moves in the direction of the arrow X1 shown in FIGS. 1 and 2 will be described. In this embodiment, a plurality of types of magnetic patterns having different residual magnetic flux density Br and magnetic permeability μ are formed in the magnetic region 1 a of the medium 1. More specifically, the medium 1 is formed with a first magnetic pattern printed with a magnetic ink containing a hard material and a second magnetic pattern printed with a magnetic ink containing a soft material. Here, the magnetic ink containing the hard material has a high level of residual magnetic flux density Br when a magnetic field is applied, as shown in FIG. 6B1 by a hysteresis loop, such as residual magnetic flux density Br and permeability μ. The permeability μ is low. On the other hand, magnetic ink containing a soft material has a low residual magnetic flux density Br when a magnetic field is applied as shown in FIG. 6 (c1), but has a high magnetic permeability μ.

Therefore, as will be described below, the material of the magnetic ink can be determined by measuring the residual magnetic flux density Br and the magnetic permeability μ. More specifically, since the magnetic permeability μ has a correlation with the holding force Hc, in this embodiment, the residual magnetic flux density Br and the holding force Hc are measured, and the residual magnetic flux density Br is measured. And the holding force Hc differ depending on the magnetic ink (magnetic material). Therefore, the material of the magnetic ink can be determined. Further, the measured values of the residual magnetic flux density Br and the magnetic permeability μ (holding force Hc) vary depending on the density of the ink and the distance between the medium 1 and the magnetic sensor device 20, but in this embodiment, the magnetic sensor device 20 is the same. Since the residual magnetic flux density Br and the magnetic permeability μ (holding force Hc) are measured at the position, the material of the magnetic ink can be reliably determined according to the ratio of the residual magnetic flux density Br and the holding force Hc.

  In the magnetic pattern detection apparatus 100 of the present embodiment, when the medium 1 moves in the direction indicated by the arrow X1 and passes through the magnetic sensor apparatus 20, first, a magnetic field is applied from the first magnetic field application magnet 31 to the medium 1, and the magnetic field The medium 1 after is applied passes through the magnetic sensor element 40. Until that time, the detection coil 49 outputs a signal corresponding to the BH curve of the sensor core 41 shown in FIG. 6 (a2), as shown in FIG. 6 (a3). Therefore, the signals output from the addition circuit 64 and the subtraction circuit 65 shown in FIG. 5 are as shown in FIG. 6 (a4).

  Here, when the first magnetic pattern is formed on the medium 1 with the magnetic ink containing a hard material such as ferrite powder, the first magnetic pattern has a high level as shown in FIG. It has a residual magnetic flux density Br. Therefore, as shown in FIG. 7A1, when the medium 1 passes through the magnetic field application magnet 30, the first magnetic pattern becomes a magnet by the magnetic field from the magnetic field application magnet 30. For this reason, the signal output from the detection coil 49 receives a DC bias from the first magnetic pattern as shown in FIG. 6 (b2), and is shown in FIG. 6 (b3) and FIG. 7 (a2). Change to waveform. That is, the peak voltage and the bottom voltage of the signal S0 are shifted in the same direction as indicated by arrows A1 and A2, and the shift amount of the peak voltage and the shift amount of the bottom voltage are different. Moreover, the signal S0 changes as the medium 1 moves. Therefore, the first signal S1 output from the adder circuit 64 shown in FIG. 5 is as shown in FIG. 6B4 and fluctuates every time the first magnetic pattern of the medium 1 passes through the magnetic sensor element 40. . Here, since the magnetic permeability μ is low in the first magnetic pattern formed by the magnetic ink containing the hard material, the first magnetic pattern has an influence on the shift of the peak voltage and the bottom voltage of the signal S0. It can be considered that only the residual magnetic flux density Br. Therefore, the second signal S2 output from the subtraction circuit 65 shown in FIG. 5 does not change even when the first magnetic pattern of the medium 1 passes through the magnetic sensor element 40, and the signal shown in FIG. 6 (b4). It is the same.

  On the other hand, when the second magnetic pattern is formed on the medium 1 with magnetic ink containing a soft material such as soft magnetic stainless steel powder, the hysteresis loop of the second magnetic pattern is shown in FIG. As shown, the level of the residual magnetic flux density Br is low through the inside of the hysteresis curve of the first magnetic pattern with the magnetic ink containing the hard material shown in FIG. 6 (b1). For this reason, even after the medium 1 passes through the magnetic field applying magnet 30, the second magnetic pattern has a low residual magnetic flux density Br. However, since the magnetic permeability μ is high, the second magnetic pattern functions as a magnetic material as shown in FIG. For this reason, as shown in FIG. 6C2, the signal output from the detection coil 49 is increased in the magnetic permeability μ due to the presence of the second magnetic pattern, so that the signals shown in FIG. 6C3 and FIG. The waveform changes to b2). That is, the peak voltage of the signal S0 is shifted to the higher side as indicated by the arrow A3, while the bottom voltage is shifted to the lower side as indicated by the arrow A4. At that time, the absolute value of the shift amount of the peak voltage and the shift amount of the bottom voltage are substantially equal. Moreover, the signal S0 changes as the medium 1 moves. Therefore, the second signal S2 output from the subtraction circuit 65 shown in FIG. 5 is as shown in FIG. 6C4, and fluctuates every time the second magnetic pattern of the medium 1 passes through the magnetic sensor element 40. . Here, since the second magnetic pattern formed by the magnetic ink containing the soft material has a low residual magnetic flux density Br, it is the second magnetic pattern that affects the shift of the peak voltage and the bottom voltage of the signal. It can be considered that only the magnetic permeability μ of. Therefore, the first signal S1 output from the adder circuit 64 shown in FIG. 5 does not change even when the second magnetic pattern of the medium 1 passes through the magnetic sensor element 40, and the signal shown in FIG. 6 (c4). It is the same.

(Specific detection results)
FIG. 8 is an explanatory diagram showing the result of detecting magnetic patterns from different types of media 1 using the magnetic pattern detection device 100 of the basic configuration example .

  In the magnetic pattern detection apparatus 100 of the present embodiment, the first signal S1 obtained by adding the peak value and the bottom value of the signal output from the magnetic sensor element 40 in the adding circuit 64 is a signal corresponding to the residual magnetic flux density level of the magnetic pattern. By monitoring the first signal S1, it is possible to detect the presence and position of the first magnetic pattern formed by the magnetic ink containing the hard material. The second signal S2 obtained by subtracting the peak value and the bottom value of the signal output from the magnetic sensor element 40 in the subtraction circuit 65 is a signal corresponding to the magnetic permeability μ of the magnetic pattern. If monitored, it is possible to detect the presence and position of the second magnetic pattern formed by the magnetic ink containing the soft material. Therefore, the presence / absence and formation position of each of the magnetic patterns in the medium 1 of a plurality of types of magnetic patterns having different residual magnetic flux density Br and magnetic permeability μ when a magnetic field is applied are based on both the residual magnetic flux density level and the magnetic permeability level. Can be identified.

  Therefore, when the medium 1 on which the first magnetic pattern is formed with the magnetic ink containing the hard material and the medium 1 on which the second magnetic pattern is formed with the magnetic ink containing the soft material are inspected, FIG. The results shown in a) and (b) can be obtained, and by comparing such signal patterns, the presence / absence, type, formation position, and shade of the magnetic pattern can be detected, and the authenticity of the medium 1 is determined. can do. Further, when the two media 1 on which both the first magnetic pattern and the second magnetic pattern are formed are inspected, the result shown in FIG. 8C can be obtained. The presence / absence, type, formation position, and density of the magnetic pattern can be detected, and the authenticity of the medium 1 can also be determined.

(Main effects of this form)
As described above, in the magnetic sensor device 20 of the present embodiment, the sensor core 41 of the magnetic sensor element 40 has a plurality of magnetic flux collectors protruding toward the medium moving path 11 from the body portion 42 extending in the width direction W40. The projecting protrusions 43 (magnetism collecting protrusions 431 and 432) are separated from each other in the width direction W40, and a detection coil 49 (detection coils 491 and 492) is wound around the plurality of magnetism collecting protrusions 43. An exciting coil 48 is wound around the body portion 42. For this reason, when the exciting coil 48 is energized, a magnetic flux is formed around the magnetic flux collecting projection 43, so that a change in the magnetic flux is detected via the detection coil 49 wound around the magnetic flux collecting projection 43. For example, magnetic characteristics such as the magnetic permeability of the medium 1 can be detected.

  Here, the magnetic sensor element 40 is arranged so that the thickness direction T40 faces the moving direction X of the medium 1, and the magnetic flux collecting projection 43 and the detection coil 49 are arranged with respect to the moving direction X of the medium 1. It is provided at a position spaced apart in the medium width direction Y that is orthogonal. For this reason, in the magnetic sensor element 40, as shown in FIG. 2C, the area in which the sensor core 41 exists and the area in which the sensor core 41 exists from the width direction W40 (the medium orthogonal to the moving direction X of the medium 1). The sensitivity is substantially equal to a position slightly shifted in the width direction Y), and the detection range in the medium width direction Y orthogonal to the moving direction X of the medium 1 is wide.

In addition, since a plurality of magnetic sensor elements 40 are arranged in the medium width direction Y, the magnetic characteristics can be detected from the entire medium width direction Y of the medium 1. Moreover, the magnetic sensor element 40 of this embodiment has a relatively high sensitivity even at a position shifted from the magnetic sensor element 40 in the width direction W40 (the medium width direction Y perpendicular to the moving direction X of the medium 1). As shown in FIG. 2C, the detection sensitivity is not significantly lowered even in a region corresponding to the area between two magnetic sensor elements 40 adjacent in the medium width direction Y. Therefore, the magnetic sensor device 20 of the present embodiment has a wide detection range in the medium width direction Y, and the detection sensitivity is equal over the wide range. Here, the sensitivity of the portion corresponding to between the magnetic sensor elements 40 in the medium width direction Y is affected by the distance between the adjacent magnetic sensor elements 40, but in this embodiment, the size of the magnetic sensor element 40 is large. Since the width direction W40 is oriented in the medium width direction Y, the number of magnetic sensor elements 40 in the medium width direction Y is reduced by a smaller number of magnetic sensor elements 40 than in the case where the thickness direction T40 is oriented in the medium width direction Y. It is possible to realize the magnetic sensor device 2 in which the sensitivity corresponding to the intermediate portion is stable.

  In the present embodiment, the dimension of the magnetic sensor element 40 in the thickness direction T40 is small. For this reason, the size of the magnetic sensor device 20 in the movement direction X can be reduced, and the resolution in the movement direction X can be improved.

  In this embodiment, the detection coils 49 (detection coils 491, 492) wound around each of the plurality of magnetic flux collecting projections 43 (magnetism collecting projections 431, 432) are electrically connected in series. ing. For this reason, an output in which the detection results of the two detection coils 491 and 492 are summed can be obtained.

  Further, since the exciting coil 48 is wound around a portion sandwiched between two magnetism-collecting projections 43 (magnetism-collecting projections 431 and 432) adjacent in the width direction W40, as in this embodiment, In any case where the number of the magnetic flux collecting projections 43 is two and the number of the magnetic flux collecting projections 43 is three or more as in the form described later, two adjacent magnetic flux collection points 43 in the width direction W40. A magnetic flux can be formed between the magnetic projections 43.

  Furthermore, since the sensor core 41 includes the protrusion 44 that protrudes from the body portion 42 to the opposite side of the magnetic flux collection protrusion 43, the magnetic resistance when viewed from the exciting coil 48 can be reduced. Therefore, since the magnetic flux generated when the same current is passed can be increased, the sensitivity can be improved. Further, when the flux gate method for saturating the sensor core 41 is employed as in the present embodiment, the drive current can be reduced, so that current consumption and heat generation can be reduced. Further, if a differential coil is wound around the protrusion 44, the magnetic characteristic of the medium 1 is detected using the difference between the detection result of the detection coil 49 and the detection result of the differential coil. Can do. Therefore, disturbances such as temperature changes can be compensated.

  Furthermore, the sensor core 41 includes the amorphous thin magnetic material layer 41c and the nonmagnetic first and second substrates 41a and 41b sandwiching the amorphous magnetic material layer 41c on both sides. The dimension in the thickness direction T40 is considerably small. For this reason, the size of the magnetic sensor device 20 in the movement direction X can be reduced, and the resolution in the movement direction X can be improved.

In the magnetic sensor device 20 of the present embodiment, the magnetic field application magnets 30 are arranged as the first magnetic field application magnet 31 and the second magnetic field application magnet 32 on both sides of the magnetic sensor element 40 in the moving direction of the medium 1. Has been. For this reason, the magnetic field applying magnet 30 is not disposed at a position overlapping the magnetic sensor element 40 in the vertical direction. Therefore, even when magnetic powder is adsorbed to the magnetic field application magnet 30 (the first magnetic field application magnet 31 and the second magnetic field application magnet 32), the magnetic powder is prevented from adhering to the magnetic sensor element 40. Can do. In addition, since the magnetic field application first magnet 31 and the magnetic field application second magnet 32 are arranged on both sides of the moving direction of the medium 1 with respect to the magnetic sensor element 40, Since the magnetic field of the first magnetic field application magnet 31 and the magnetic field of the second magnetic field application magnet 32 are formed on both sides in the direction of movement 1, the influence of the first magnetic field application magnet 31 on the magnetic sensor element 40 and the magnetic The influence of the magnetic field application second magnet 32 on the sensor element 40 can be offset. Further, as shown in FIG. 1, the medium 1 moving in the direction indicated by the arrow X <b> 1 is magnetized by the magnetic field applying first magnet 31, and then the magnetic field is applied to the medium 1 after being magnetized by the magnetic sensor element 40. Can be detected, and the medium 1 that moves in the direction indicated by the arrow X2 is magnetized by the magnetic field application second magnet 32, and then magnetized by the magnetic sensor element 40. The magnetic flux in a state where a bias magnetic field is applied to the medium 1 can be detected. Therefore, if the magnetic pattern detection apparatus 100 of this embodiment is used for a depositing / dispensing machine, it is possible to determine the authenticity of the deposited medium 1 and also to determine the authenticity of the dispensed medium 1. .

  Further, in the magnetic pattern detection device 100 of this embodiment, the common magnetic sensor device 20 detects the presence / absence and formation position of each magnetic pattern based on both the residual magnetic flux density level and the magnetic permeability level. There is no time difference between the measurement and the permeability level measurement. Therefore, even when the measurement is performed while moving the magnetic sensor device 20 and the medium 1, the signal processing unit 60 can perform highly accurate detection with a simple configuration. In addition, since the transport device 10 is also required to have running stability only at a location that passes through the magnetic sensor device 20, the configuration can be simplified.

  Furthermore, according to the magnetic pattern detection apparatus 100 of the present embodiment, the medium 1 on which the magnetic pattern is formed by the magnetic ink including both the hard material and the soft material, and the material positioned between the hard material and the soft material are included. The magnetic pattern can also be detected for the medium 1 on which the magnetic pattern is formed with the magnetic ink. That is, as for the magnetic pattern whose magnetic characteristics are located between the first magnetic pattern and the second magnetic pattern, as shown in FIG. 6 (d1), the hysteresis loop has a hard loop as shown in FIG. 6 (b1). Since it is located between the hysteresis loop of the magnetic pattern of the material and the hysteresis loop of the magnetic pattern of the soft material shown in FIG. 6 (c1), the signal pattern shown in FIG. 6 (d4) can be obtained. In addition, the presence or absence and the formation position can be detected.

[Embodiment]
FIG. 9 is an explanatory diagram of the magnetic sensor element 40 used in the magnetic sensor device 20 according to the embodiment to which the present invention is applied . FIGS. 9A, 9B, and 9C are explanatory diagrams when the number of magnetic flux collecting projections 43 is three, explanatory diagrams when the number of magnetic flux collecting projections 43 is four, and magnetic flux collection. It is explanatory drawing in case the number of the protrusions 43 for use is five. The embodiment of the present invention is a magnetic sensor device 20 using the magnetic sensor element 40 shown in FIGS. 9A and 9C. The magnetic sensor device 20 using the magnetic sensor element 40 shown in FIG. 9B is a reference example.

In the magnetic sensor element 40 described with reference to FIG. 1 to FIG. 8, the two magnetic flux collecting projections 43 are formed on the sensor core 41, as shown in FIGS. 9A, 9 </ b> B, and 9 </ b> C. As described above, a configuration in which three or more magnetic flux collecting projections 43 protrude from the body portion 42 of the sensor core 41 may be employed. Even in such a configuration, the detection coil 49 is wound around each of the magnetic flux collecting projections 43 and sandwiched between the magnetic flux collecting projections 43 adjacent to each other in the width direction W40 in the body portion 42, as in the above embodiment. An exciting coil 48 is wound around this portion. Therefore, the number of the magnetic flux collecting projections 43, the detection coils 49, and the exciting coils 48 is as follows: the number of the related magnetic flux collecting projections 43 = the number of the detection coils 49 = the number of the exciting coils 48 = the magnetic flux collecting projections 43 -1 = number of detection coils 49-1
It has become.

Of the forms shown in FIGS. 9A, 9B, and 9C, in the magnetic sensor element 40 shown in FIG. 9A, three magnetic flux collecting projections 43 (magnetism collecting projections 431 to 433). A detection coil 49 (detection coils 491 to 493) is wound around each of the two, and an excitation coil 48 (excitation coils 481, 482) is sandwiched between two adjacent magnetism collecting projections 43 in the width direction W40 in the body portion 42. ) Is wound. Further, a protrusion 44 (protrusions 441 to 443) protrudes from the body part 42 on the side opposite to the three magnetic flux collection protrusions 43 (magnetism collection protrusions 431 to 433).

  In the magnetic sensor element 40 shown in FIG. 9B, the detection coil 49 (detection coils 491 to 494) is wound around each of the four magnetic flux collection protrusions 43 (magnetism collection protrusions 431 to 434). The exciting coil 48 (exciting coils 481 to 483) is wound around three portions sandwiched by the magnetic flux collecting projections 43 adjacent in the width direction W40 in the body portion 42. Further, a protrusion 44 (protrusions 441 to 444) protrudes from the body part 42 on the side opposite to the four magnetic flux collection protrusions 43 (magnetism collection protrusions 431 to 434).

  Further, in the magnetic sensor element 40 shown in FIG. 9C, the detection coil 49 (detection coils 491 to 494) is wound around each of the five magnetic flux collection protrusions 43 (magnetism collection protrusions 431 to 434). The exciting coil 48 (exciting coils 481 to 483) is wound around four positions sandwiched by the magnetic flux collecting projections 43 adjacent in the width direction W40 in the body portion 42. Further, a protrusion 44 (protrusions 441 to 445) protrudes from the body part 42 on the side opposite to the five magnetic flux collecting protrusions 43 (magnetism collection protrusions 431 to 435).

  Also in the magnetic sensor element 40 having such a configuration, the detection coils 49 adjacent in the width direction W40 are wound in opposite directions, and the plurality of detection coils 49 are electrically connected in series as in the above embodiment. ing. In the magnetic sensor element 40, the exciting coils 48 adjacent in the width direction W40 are wound in opposite directions, and the plurality of exciting coils 43 are electrically connected in series or in parallel.

  In addition, as described with reference to FIGS. 2A and 2B, a plurality of magnetic sensor elements 40 are arranged in the medium width direction Y. At this time, the winding direction of the detection coil 49 matches between the plurality of magnetic sensor elements 40. Further, when a common exciting current is supplied to each exciting coil 48 of the plurality of magnetic sensor elements 40, as shown in FIG. 10B, when there are four magnetizing projections 43 (exciting coil 48). Is an odd number), the winding direction of the exciting coil 48 is matched between the adjacent magnetic sensor elements 40. On the other hand, as shown in FIGS. 10A and 10C, when there are three or five magnetism-collecting projections 43 (when the exciting coil 48 is an even number), it is between the adjacent magnetic sensor elements 40. The winding direction of the exciting coil 48 is reversed. With this configuration, the magnetic poles of the magnetic flux collecting projections 43 adjacent to each other between the adjacent magnetic sensor elements 40 are reversed, so that a magnetic flux can be generated between the adjacent magnetic sensor elements 40.

  Even in the magnetic sensor device 20 configured as described above, the magnetic sensor element 40 is arranged so that the thickness direction T40 faces the moving direction X of the medium 1 in the magnetic pattern detection device 100 shown in FIG. The projection 43 and the detection coil 49 are provided at positions separated in the medium width direction Y orthogonal to the moving direction X of the medium 1. For this reason, in the magnetic sensor element 40, the region where the sensor core 41 exists, and the position slightly shifted from the region where the sensor core 41 exists in the width direction W40 (medium width direction Y orthogonal to the moving direction X of the medium 1). The effect similar to that of the first embodiment is obtained such that the sensitivity is substantially the same and the detection range in the medium width direction Y orthogonal to the moving direction X of the medium 1 is wide.

[Another embodiment]
FIG. 10 is an explanatory view of a magnetic sensor element 40 used in a magnetic sensor device 20 according to another embodiment to which the present invention is applied . FIGS. 10 (a), 10 (b), and 10 (c) are magnetic flux collectors. It is explanatory drawing in case the number of the protrusions 43 for three is explanatory drawing in case the number of the magnetic projections 43 is four, and explanatory drawing in case the number of the magnetic collection protrusions 43 is five. The embodiment of the present invention is a magnetic sensor device 20 using the magnetic sensor element 40 shown in FIGS. 10 (a) and 10 (c). The magnetic sensor device 20 using the magnetic sensor element 40 shown in FIG. 10B is a reference example.

In the form shown in FIG. 9, the magnetic flux density is lower at both ends of the width direction W40 than in the width direction W40. In such a case, the number of turns of the detection coil 49 is as follows. In the case shown in FIG. 9A (number of detection coils 49 = 3), the number of turns of the detection coils 491 and 493> the number of turns of the detection coil 492 In the case shown in FIG. 9B (the number of detection coils 49 = 4) The number of turns of the detection coils 491, 494> the number of turns of the detection coils 492, 493 The form shown in FIG. 9C (the number of detection coils 49) = 5) Number of turns of detection coils 491, 495> Number of turns of detection coils 492, 493, 494 or Number of turns of detection coils 491, 495
> Number of windings of detection coils 492 and 494
As shown in the number of turns of the detection coil 493, if the number of turns of the detection coil 49 at both ends is made larger than the number of turns of the other detection coils 49, the sensitivity in the width direction W40 can be equalized.

At that time, as shown in FIGS. 10A, 10B, and 10C, the thickness of the magnetic flux collecting projection 43 is set to the following relationship (the number of detection coils 49 = 3) as shown in FIG. ) The thickness of the magnetic flux collecting projections 431 and 433 <the thickness of the magnetic flux collection projection 432 In the case of the configuration shown in FIG. 10B (the number of detection coils 49 = 4), the magnetic flux collection projections 431, Thickness of 434 <Thickness of magnetic flux collection protrusions 432, 433 In the case of the configuration shown in FIG. 10C (the number of detection coils 49 = 5), the thickness of magnetic flux collection protrusions 431, 435 <for magnetic flux collection Thickness of protrusions 432, 433, 434 or Thickness of magnetic flux collecting protrusions 431, 435
<Thickness of magnetic flux collecting projections 432 and 434
<As shown in the thickness of the magnetic flux collecting projections 433, if the thickness of the magnetic flux collecting projections 43 at both ends is made larger than the thickness of the other magnetic flux collecting projections 43, the detection coils 49 at both ends There is no problem in winding more times than the other detection coils 49.

(Other embodiments)
In the above embodiment, when the medium 1 and the magnetic sensor device 20 are moved relative to each other, the medium 1 is moved. However, a configuration in which the medium 1 is fixed and the magnetic sensor device 20 moves may be employed. Moreover, in the said form, although the permanent magnet was used for the magnet 30 for magnetic field application, you may use an electromagnet.

DESCRIPTION OF SYMBOLS 1 Medium 11 Medium moving path 20 Magnetic sensor apparatus 30 Magnetic field application magnet 40 Magnetic sensor element 41 Sensor core 42 Sensor core trunk 43 Sensor core magnetic flux projection 48 Excitation coil 49 Detection coil 100 Magnetic pattern detection apparatus

Claims (6)

A magnetic sensor device comprising a magnetic sensor element for detecting a magnetic characteristic of a relatively moving medium,
The magnetic sensor element has three or more odd number of magnetic flux collecting protrusions protruding from a body portion extending in the width direction of the magnetic sensor element toward the medium moving path side of the medium and spaced apart from each other in the width direction. Each of the plurality of magnetism-collecting protrusions, the sensor core having a portion , the exciting coil wound around the even-numbered portions sandwiched between the magnetism-projecting protrusions adjacent in the width direction in the body portion and wound on the detection coil provided with a thickness direction orthogonal to both the protruding direction of the width direction and the focusing magnetizing projection thereof faces in the direction of movement of the medium, the A plurality are arranged in a direction crossing the moving direction of the medium,
The dimension in the width direction of the sensor core is larger than the dimension in the thickness direction,
In the magnetic sensor element, the exciting coils adjacent in the width direction are wound in opposite directions,
A magnetic sensor device characterized in that the winding direction of the exciting coil is reversed between the adjacent magnetic sensor elements .   The magnetic sensor device according to claim 1, wherein the detection coil wound around each of the plurality of magnetic flux collecting projections is electrically connected in series. Of the three or more odd number of magnetic flux collecting protrusions, the detection coil wound around the magnetic flux collecting protrusions located at both ends in the width direction is wound around another magnetic flux collecting protrusion. The magnetic sensor device according to claim 1, wherein the number of turns is larger than that of the detection coil. 2. The magnetic flux collecting protrusions located at both ends in the width direction among three or more odd numbers of magnetic flux collecting protrusions are narrower than other magnetic flux collecting protrusions. 3. The magnetic sensor device according to 3. 5. The magnetic sensor device according to claim 1, wherein the sensor core includes a protrusion that protrudes from the body portion to the opposite side of the magnetic flux collection protrusion. 6. The said sensor core is provided with the amorphous magnetic material layer and the nonmagnetic board | substrate which pinches | interposes this amorphous magnetic material layer on both surfaces side, The Claim 1 thru | or 5 characterized by the above-mentioned.
Magnetic sensor device.

Images