JP5666897B2 - Multi-channel magnetic sensor device manufacturing method and multi-channel magnetic sensor device - Google Patents

Description

  The present invention relates to a method for manufacturing a multi-channel magnetic sensor device and a multi-channel magnetic sensor device mounted on a magnetic pattern detection device that detects a magnetic pattern of a medium such as a banknote printed with magnetic ink.

  A magnetic pattern detection device for detecting a magnetic pattern of a medium conveyed along a medium conveyance surface includes a magnet for magnetizing the medium and a magnetic sensor device for reading the magnetic pattern of the medium magnetized by the magnet. Things are known. In the magnetic pattern detection device described in Patent Document 1, the magnetic sensor device includes a plurality of magnetic sensor elements and a frame on which the plurality of magnetic sensor elements are mounted. In this document, the sensor surface of each magnetic sensor element is arranged on the same plane as the medium transport surface in order to detect the magnetic pattern of the medium with high accuracy.

JP 2009-163336 A

  In a multi-channel magnetic sensor device in which a plurality of magnetic sensor elements are mounted on a frame, the gap between the magnetic sensor element and the medium is not magnetic unless the sensor surfaces of all the magnetic sensor elements are located on the same plane. Since each sensor element is different, the output level of the detection signal from the magnetic sensor element is different, which causes a problem that the magnetic pattern cannot be detected accurately. Here, in order to position the sensor surfaces of all the magnetic sensor elements on the same plane, each magnetic sensor element is positioned with the sensor surface coinciding with a predetermined reference sensor surface to form a frame. It is conceivable that the sensor surfaces of a plurality of magnetic sensor elements mounted on the frame are collectively ground.

  However, in such a method, the position of the sensor surface with respect to the frame may vary from frame to frame due to dimensional tolerances of the frame. Here, since the magnetic sensor element is mounted on the magnetic pattern detection device via the frame, if the position of the sensor surface with respect to the frame varies, the gap between the medium conveyance surface of the magnetic pattern detection device and the sensor surface is increased. The problem arises that the output level of the detection signal from the magnetic sensor element varies depending on the magnetic sensor device.

  In view of such a point, an object of the present invention is to manufacture a multi-channel magnetic sensor device capable of positioning all sensor surfaces of a plurality of sensor elements on a predetermined same plane defined with respect to a frame. It is to provide a method and a multi-channel magnetic sensor device.

In order to solve the above-described problems, the present invention provides a method for manufacturing a multi-channel magnetic sensor device in which a plurality of magnetic sensor elements are mounted on a frame, and a plurality of parallel through the frame from one side to the other side. Frame preparation step for preparing a mounting hole and a grinding reference surface orthogonal to the axis of each mounting hole, and each magnetic sensor element in the mounting hole with the sensor surface facing one side. An insertion step of inserting a sensor element, and the magnetic sensor element is positioned in the direction of the axis of the mounting hole with reference to the grinding reference surface, and the sensor surface protrudes from the first opening on one side of the mounting hole. A positioning step, a fixing step of filling each mounting hole with resin and fixing each magnetic sensor element to the frame, and a planar polishing with respect to the grinding reference surface. To and a surface grinding step, further, during the insertion step and the fixing step includes the wear plate disposing step first opening is disposed abrasion plate to the end surface of the frame that is exposed In the fixing step, the wear-resistant plate is fixed to the frame by the resin, and the frame has a rectangular shape when viewed from the direction of the axis of the mounting hole, and the other side of the frame Projections protruding to the other side are provided at the four corners of the end face, and the other end face of each protrusion is the grinding reference surface .

According to the present invention, the sensor surface of each magnetic sensor element is positioned on the same plane by surface grinding. Further, since the positioning of the magnetic sensor element with respect to the frame is performed with reference to the grinding reference surface of the frame for surface grinding of the sensor surface, the position of the sensor surface is the ground reference surface of the frame regardless of the dimensional tolerance of the frame. Is defined at a predetermined position. Therefore, it can be avoided that the position of the sensor surface with respect to the frame varies from frame to frame. Furthermore, the sensor surface of the magnetic sensor element can be protected by being surrounded by a wear-resistant plate.

  In the present invention, in the inserting step, it is preferable that the magnetic sensor element is brought into contact with an inner peripheral surface of the mounting hole and the magnetic sensor element is positioned in a direction orthogonal to the axis of the mounting hole. In this way, the positions of the magnetic sensor elements can be accurately defined.

In the present invention, in the surface grinding step, it is preferable that the sensor surface is surface ground together with the surface of the wear-resistant plate, using the grinding reference surface as a reference. Thus, because the sensor surface of the surface and the magnetic sensor element of the wear plate can be positioned on the same plane, it is possible to reduce the wear of the sensor surface by the wear plate.

  In this case, in the positioning step, it is preferable that the sensor surface is protruded from the first opening of the mounting hole by a thickness more than the thickness of the wear resistant plate. In this way, the sensor surface can always be exposed after surface grinding.

Next, the present invention provides a multi-channel magnetic sensor device in which a plurality of magnetic sensor elements are mounted on a frame, and has a wear-resistant plate, and the frame includes a plurality of parallel passages penetrating from one side of the frame to the other side. It has mounting holes and a grinding reference surface orthogonal to the axis of each mounting hole, and each magnetic sensor element is inserted into each mounting hole with the sensor surface facing one side, and the grinding reference surface is used as a reference. The sensor surface is positioned so as to protrude from the first opening on one side of the mounting hole, and is fixed to the frame by a resin filled in the mounting hole . 1 is placed on the end surface of the frame where the opening is exposed, and is fixed to the frame by the resin, and the contour shape when the frame is viewed from the direction of the axis of the mounting hole is a rectangle, Previous The four corners of the other side end face of the frame has projections is provided to protrude on the other side, the end surface of the other side of the projections, the a grinding reference plane, the sensor surface is the ground reference plane The surface of each magnetic sensor element is positioned on the same plane by surface grinding as a reference.

According to the present invention, the sensor surface of each magnetic sensor element is positioned on the same plane by surface grinding. Further, since the positioning of the magnetic sensor element with respect to the frame is performed with reference to the grinding reference surface of the frame for surface grinding of the sensor surface, the position of the sensor surface is the ground reference surface of the frame regardless of the dimensional tolerance of the frame. Is defined at a predetermined position. Therefore, it can be avoided that the position of the sensor surface with respect to the frame varies from frame to frame. Furthermore, the sensor surface of the magnetic sensor element can be protected by being surrounded by a wear-resistant plate.

  In the present invention, it is desirable that each magnetic sensor element is positioned in a direction perpendicular to the axis of the mounting hole by contacting the inner peripheral surface portion of each mounting hole. In this way, the positions of the magnetic sensor elements can be accurately defined.

In the present invention, the wear-resistant plate and the sensor surface are positioned on the same plane by subjecting the surface of the wear-resistant plate to surface grinding with the sensor surface with respect to the grinding reference surface. desirable. Thus, because the sensor surface of the surface and the magnetic sensor element of the wear plate can be positioned on the same plane, it is possible to reduce the wear of the sensor surface by the wear plate.

  According to the present invention, the position of the sensor surface is defined at a predetermined position with respect to the grinding reference surface of the frame regardless of the dimensional tolerance of the frame. Therefore, it can be avoided that the position of the sensor surface with respect to the frame varies from frame to frame. Therefore, when the magnetic sensor device is mounted on the magnetic pattern detection device, it is avoided or reduced that the gap between the sensor surface of the magnetic sensor element mounted on the magnetic pattern detection device via the frame and the medium transport surface changes. This also reduces the characteristic variation between the magnetic sensor elements.

It is explanatory drawing of the magnetic pattern detection apparatus carrying the magnetic sensor apparatus of this invention. It is explanatory drawing of the magnetic sensor unit of this invention. It is a perspective view of a cover board, a surface side cover board, and a back surface side cover board. It is the front view, side view, and top view of a magnetic sensor apparatus. It is sectional drawing of a magnetic sensor apparatus. It is the front view, side view, top view, and bottom view of a frame. It is the front view, side view, and top view of a magnetic sensor element. It is explanatory drawing of a magnetic sensor element. It is explanatory drawing of a conductive member. It is explanatory drawing of the magnetic sensor apparatus inserted in the case. It is explanatory drawing of the magnetic sensor apparatus in the middle of manufacture. It is the excitation waveform and detection waveform of a magnetic sensor element.

  Hereinafter, a magnetic pattern detection device equipped with a magnetic sensor device to which the present invention is applied will be described with reference to the drawings.

(overall structure)
FIG. 1 is an explanatory view schematically showing a configuration of a main part of a magnetic pattern detection device equipped with a magnetic sensor device to which the present invention is applied. As shown in FIG. 1, the magnetic pattern detection device 1 is provided in a medium conveyance mechanism 4 that conveys a sheet-like medium 2 such as banknotes and securities along a medium conveyance path 3, and the medium conveyance path 3. A magnetic sensor unit 5 for detecting the magnetic pattern of the medium 2 at the magnetic reading position A is provided. In the following description, for convenience, the upper and lower parts of each member will be described according to the upper and lower parts of the figure.

(Magnetic sensor unit)
FIG. 2A is a perspective view showing a layout of the first magnetizing magnet, the second magnetizing magnet, and the magnetic sensor device in the magnetic sensor unit 5, and FIG. 2B is a cross-sectional configuration of the magnetic sensor unit 5. FIG. 3A is a perspective view of the cover plate as viewed from below, FIG. 3B is a perspective view of the cover plate as viewed from below, and FIG. It is the perspective view seen from. In FIG. 2, in order to explain the arrangement of the cover plate, the first magnetizing magnet, and the second magnetizing magnet, the configuration of the magnetic sensor device is schematically shown.

  The magnetic sensor unit 5 includes a plurality of first magnetizing magnets 6 for magnetizing the medium 2 passing through the magnetic reading position A from the first direction X1 in the medium conveying direction X, and the magnetic reading position A in the first direction X1. Is magnetized by a plurality of second magnetizing magnets 7 that magnetize the medium 2 passing from the second direction X2 opposite to the first direction X2, and the first magnetizing magnet 6 or the second magnetizing magnet 7. Is provided with a magnetic sensor device 8 for reading the magnetic pattern of the medium 2 passing through the magnetic reading position A. A case 10 on which the magnetic sensor device 8 is mounted and a rectangular cover plate 11 attached to the upper end portion of the case 10 are provided. The cover plate 11 holds the first magnetizing magnet 6 and the second magnetizing magnet 7, and the medium 2 through which the first magnetizing magnet 6 and the second magnetizing magnet 7 pass the magnetic reading position A. Therefore, the upper surfaces of the first and second magnetizing magnets 6 and 7 are covered so as not to be worn out.

  Case 10 is formed of a conductive material such as metal. As shown in FIG. 2B, a rectangular recess 102 for attaching the cover plate 11 is formed in the center portion of the upper end surface 101 of the case 10 in the medium transport direction X. On both sides of the concave portion 102 in the medium conveying direction X, inclined surfaces 103 are provided that are inclined downward toward the outside.

  The recess 102 has a constant depth and extends with a constant width in a direction orthogonal to the medium transport direction X. A magnetic sensor device 8 is configured in the central portion of the recess 102 in the medium conveyance direction X. The upper end surface of the magnetic sensor device 8 is a sensor surface 8 a and is located on the same plane as the upper end surface 101 of the case 10. The magnetic sensor device 8 includes a plurality of magnetic sensor elements 13 arranged at a predetermined pitch in a direction orthogonal to the medium transport direction X.

  The cover plate 11 includes a front-side cover plate 14 on which a medium transport surface 11a for transporting the medium 2 is formed on the front surface 14a, and a back-side cover plate 15 stacked and fixed on the back surface 14b of the front-side cover plate 14. A composite plate made of

  The front surface side cover plate 14 is a thin metal plate having a constant thickness, and has a rectangular outline shape. Further, the front surface side cover plate 14 includes a rectangular opening 141 in the center portion in the medium transport direction X. The opening 141 is formed by etching, for example. In this example, the thickness of the surface side cover plate 14 is 0.3 mm or less, preferably about 0.1 mm. Therefore, the surface side cover plate 14 is in a so-called “slippery” state, and its rigidity is reduced.

  The back surface side cover plate 15 is a plate material of a metal plate thicker than the front surface side cover plate 14, and the thickness dimension of the back surface side cover plate 15 is about 0.3 to 0.5 mm in this example. The back surface side cover plate 15 has a constant thickness, and has the same thickness dimension as the thickness dimension of the first magnetizing magnet 6 and the second magnetizing magnet 7. The contour shape of the back surface side cover plate 15 is the same as the contour shape of the front surface side cover plate 14, and the back surface side cover plate 15 includes an opening portion 151 having the same shape as the opening portion 141 at a position overlapping the opening portion 141. Yes. The opening 141 of the front cover plate 14 and the opening 151 of the back cover plate 15 constitute an opening 111 of the cover plate 11.

  Further, as shown in FIG. 3 (c), the back surface side cover plate 15 is used for mounting a plurality of magnets 16 constituting the first magnetizing magnet 6 on the upstream side of the opening 151 in the first direction X1. A first mounting hole (insertion hole) 152 is provided, and a second mounting hole (for mounting a plurality of magnets 16 constituting the second magnetizing magnet 7 on the upstream side in the second direction X2 of the opening 151). Insertion hole) 153 is provided. Each of the first mounting hole 152 and the second mounting hole 153 includes a plurality of mounting holes 154, and each mounting hole 154 is arranged at a predetermined pitch in a direction orthogonal to the medium transport direction X. The opening 151, the first mounting hole 152, and the second mounting hole 153 are formed by, for example, etching.

  Here, the front surface side cover plate 14 and the rear surface side cover plate 15 are both made of stainless steel, and the front surface side cover plate 14 and the rear surface side cover plate 15 are diffusion bonded. That is, the front surface side cover plate 14 and the back surface side cover plate 15 are integrated by being pressed and heated in a state where they are in close contact with each other, and the cover plate 11 as a whole has high rigidity.

  The first magnetizing magnet 6 is configured by each magnet 16 fitted in each mounting hole 154 of the first mounting hole 152, and the second magnetizing magnet 7 is formed in each mounting hole 154 of the second mounting hole 153. It is comprised by each magnet 16 inserted. The magnets 16 of the first magnetizing magnet 6 are arranged at a predetermined pitch in a direction orthogonal to the medium conveying direction X, and the magnets 16 of the second magnetizing magnet 7 are orthogonal to the medium conveying direction X. It is arranged at a predetermined pitch in the direction. Further, the magnet 16 of the first magnetizing magnet 6 and the magnet 16 of the second magnetizing magnet 7 overlap each other when viewed from the medium transport direction X.

  Each magnet 16 is a permanent magnet such as a ferrite or neodymium magnet, and has the same magnetic force. Each magnet 16 has a rectangular parallelepiped shape that fits into each mounting hole 154 of the back surface side cover plate 15 and has the same shape as each other. In other words, each mounting hole 154 has a shape corresponding to each magnet 16 having the same shape.

  Further, each magnet 16 is fitted in each mounting hole 154 and is held by the back surface side cover plate 15 in a state of being in contact with the back surface 14 b of the front surface side cover plate 14. In a state where each magnet 16 is held in each mounting hole 154, each magnet 16 is located on the side opposite to the surface side cover plate 14 and the portion on the surface side cover plate 14 side, as shown in FIG. The surface is a magnetic pole different from that of the portion, and the surface in contact with the back surface 14b of the front cover plate 14 functions as a magnetized surface for the medium 2 transported on the medium transport surface 11a. Here, since each magnet 16 is in contact with the back surface 14 b of the front surface side cover plate 14, the gap between the medium transport surface 11 a and each magnet 16 is defined by the plate thickness of the front surface side cover plate 14.

  When the cover plate 11 holding the first magnetizing magnet 6 and the second magnetizing magnet 7 is attached to the recess 102 of the case 10, the cover plate 11 of the magnetic sensor device 8 is placed inside the opening 111 of the cover plate 11. The medium side surface 11a of the cover plate 11 and the sensor surface 8a of the magnetic sensor device 8 are located on the same plane. In addition, the first magnetizing magnet 6 is disposed on the upstream side in the first direction X1 of the magnetic sensor device 8, and the second magnetizing magnet 7 is disposed on the upstream side in the second direction X2 of the magnetic sensor device 8. . Further, the magnetic sensor device 8 is positioned between the first magnetizing magnet 6 and the second magnetizing magnet 7, and each of the plurality of magnetic sensor elements 13 held by the magnetic sensor device 8 has a medium transport direction. When viewed from X, it overlaps with the magnet 16 of the first magnetizing magnet 6 and the magnet 16 of the second magnetizing magnet 7.

  Here, the magnetic sensor device 8 detects a magnetic flux in a state where a bias magnetic field is applied to the magnetized medium 2, and the magnetic pattern detection device 1 collates the detected waveform from the magnetic sensor device 8 with a reference waveform. As a result, the authenticity or type of the medium 2 is determined.

(Magnetic sensor device)
4A to 4C are a front view, a side view, and a top view of the magnetic sensor device 8. The front view is viewed from the medium transport direction X, and the side view is viewed from the direction Y orthogonal to the medium transport direction X. FIG. 5 is a cross-sectional view of the magnetic sensor device. 6A to 6D are a front view, a side view, a top view, and a bottom view of the frame, respectively. 7A to 7C are a front view, a side view, and a top view of the magnetic sensor element 13, respectively. FIG. 8 is an explanatory diagram of the core body, excitation coil, and detection coil of the magnetic sensor element 13.

  As shown in FIG. 4, the magnetic sensor device 8 includes a frame 20 and a plurality of magnetic sensor elements 13 held on the frame 20 with the sensor surface 13 a facing upward. The sensor surface 13 a of the magnetic sensor element 13 constitutes the sensor surface 8 a of the magnetic sensor device 8.

  The frame 20 has an elongated rectangular parallelepiped shape as a whole. As shown in FIG. 6, a plurality of mounting holes 23 penetrating from the upper end surface 21 to the lower end surface 22 of the frame 20 are formed in the frame 20 at a predetermined pitch in a direction Y orthogonal to the medium transport direction X. . The axes L of the mounting holes 23 extend in parallel to each other. On the outer peripheral side of the upper end surface 21 of the frame 20, a frame-like flange portion 24 surrounding the upper end surface 21 and protruding upward is provided. Projections 25 projecting downward are provided at the four corners of the lower end surface 22 of the frame 20, and the lower end surfaces of the projections 25 serve as grinding reference surfaces 26 orthogonal to the axis L of the mounting holes 23. . Further, as shown in FIG. 6D, a plurality of engaging protrusions 27 projecting downward are constant on the lower end surface portion 22a on the one side in the medium transport direction X of the mounting hole 23 on the lower end surface 22 of the frame 20. It is provided at intervals. The upper end opening 23a of each mounting hole 23 exposed on the upper end surface 21 has a rectangular shape as a whole. A partial blocking portion 28 that partially blocks each mounting hole 23 is provided inside the lower end opening 23 b of each mounting hole 23.

  7A to 7C are a front view, a side view, and a top view of the magnetic sensor element 13, respectively. FIG. 8 is an explanatory diagram of the core body, excitation coil, and detection coil of the magnetic sensor element 13. As shown in FIG. 7, the magnetic sensor element 13 has a three-layer structure including first and second protective plates 30 and 31 and a sensor core 32 sandwiched between the first and second protective plates 30 and 31. A core body 33 is provided. The first and second protection plates 30 and 31 are made of a non-magnetic material such as ceramics, and the sensor core 32 is made of a magnetic material such as ferrite, amorphous, permalloy, or silicon steel plate.

  As shown in FIG. 8, the core body 33 includes a body 331, a first protrusion 332 that protrudes upward from the central portion of the upper end of the body 331, and a body on the opposite side of the first protrusion 332. A second protrusion 333 that protrudes downward from the central portion of the lower end of 331 is provided. Further, a third protrusion 334 protruding from both sides of the first protrusion 332 at the upper end of the body 331 and a fourth protrusion 335 protruding from both sides of the second protrusion 333 at the lower end of the body 331 are provided. ing.

  Here, as shown in FIG. 7B, the entire surface of the other side of the sensor core 32 is covered by the second protective plate 31, but the lower end portion of the second protrusion 333 of the first protective plate 30 and the second The lower end portion of the four protrusions 335 is cut out by a predetermined width from the lower end, and the lower end portion of the second protrusion 333 and the lower end portion of the fourth protrusion 335 on one side of the sensor core 32 become an exposed portion 32a. ing.

Further, as shown in FIGS. 7 and 8, each magnetic sensor element 13 includes an excitation coil 34 for generating a bias magnetic field and a detection coil 35 for detecting the magnetic pattern of the medium 2. The exciting coil 34 is located on both sides of the first protrusion 332 and the second protrusion 333 in the body 331 and inside the third protrusion 334 and the fourth protrusion 335 via the first coil bobbin 36. It is configured by winding a coil wire. The detection coil 35 is configured by winding a coil wire around a first protrusion 332 via a second coil bobbin 37. Thereby, the tip surface of the first protrusion 332 is the sensor surface 13 a of the magnetic sensor element 13. Here, as shown in FIG. 7, four terminal pins 38 are attached to a portion of the first coil bobbin 36 located on the second protection plate 31 side, and these extend downward. Of the four terminal pins 38, the two terminal pins 38 arranged on the inner side extend downward from the inner side in the width direction of the second protrusion 333, as shown in FIG. Further, the two terminal pins 38 arranged on the outer side extend downward from the inner side in the width direction of the fourth protrusion 335. A locking pin 39 having a shorter dimension than the terminal pin 38 is attached to the center of the four terminal pins 38. The coil wire of the exciting coil 34 is locked to the locking pin 39.

  Each magnetic sensor element 13 is inserted from above into each mounting hole 23 with the sensor surface 13a facing upward. Further, as shown in FIG. 5, each core body 33 is directed in the medium transport direction X, and the first protection plate 30 is directed to the side on which the engagement protrusions 27 of the frame 20 are formed. It is inserted into the mounting hole 23. In a state where each magnetic sensor element 13 is inserted into the mounting hole 23, the partial blocking portion 28 is inserted between the second protrusion 333 and the fourth protrusion 335 of the core body 33, and the mounting hole The first protrusion 332 and the third protrusion 334 protrude from the upper end opening 23a of the second protrusion 23, and the second protrusion 333, the fourth protrusion 335, and the four terminal pins 38 protrude from the lower end opening 23b of the mounting hole 23. ing. Further, in a state where each magnetic sensor element 13 is inserted into the mounting hole 23, as shown in FIG. 4C, each magnetic sensor element 13 comes into contact with the inner peripheral surface portion 23c of the mounting hole 23 to convey the medium. They are arranged in a state of being positioned at a predetermined pitch in a direction Y orthogonal to the direction X. The predetermined pitch is the same as the arrangement pitch of the first magnetizing magnets 6 and the arrangement pitch of the second magnetizing magnets 7.

Next, two rectangular wear-resistant plates 19 are inserted inside the flange portion 24 of the frame 20 as shown in FIG. The two wear-resistant plates 19 are placed on the upper end surface 21 of the frame 20 with a predetermined gap in the medium transport direction X. Each of the two wear-resistant plates 19 is a member having a constant thickness made of ceramic or the like, and extends with a constant width in a direction orthogonal to the medium transport direction X.

  In a state where the two wear-resistant plates 19 are placed on the upper end surface 21 of the frame 20, the upper end surface 19 a of each wear-resistant plate 19 protrudes above the upper end surface of the flange portion 24. As shown in FIG. 5, the upper ends of the first protrusion 332 and the second protrusion 334 of the core body 33 of the magnetic sensor element 13 are inserted into the gap between the two wear-resistant plates 19. The upper end surfaces 19a of the two wear-resistant plates 19, the upper end surface 332a (sensor surface 13a) of the first protrusion 332 of the core body 33, and the upper end surface 334a of the third protrusion 334 are located on the same plane. ing. Here, the mounting holes 23 are filled with a resin 29, and the two wear-resistant plates 19 and the magnetic sensor elements 13 are fixed to the frame 20 by the resin 29.

  As shown in FIGS. 4A and 4B, a conductive member 41 for grounding the sensor core 32 of the magnetic sensor element 13 is attached to the lower end portion of the frame 20. FIG. 9A is a plan view of the conductive member 41, and FIG. 9B is a front view of the conductive member 41 attached to the frame 20 as viewed from the medium conveying direction X. FIG. FIG. 9 is an explanatory view schematically showing a state in which the magnetic sensor device 8 in which the conductive member 41 is attached to the lower end surface portion 22a of the frame 20 is viewed from the medium transport direction X. FIG. It is explanatory drawing which shows typically the state attached to the lower end surface part 22a.

  The conductive member 41 is a leaf spring formed by etching one metal thin plate. As shown in FIG. 5, the conductive member 41 has a plurality of spans 411 spanned from the frame 20 side to the magnetic sensor element 13 and pressed against the sensor core 32, and as shown in FIG. Are provided at both ends of the attachment portion 412 fixed to the lower end surface 22 of the frame 20 and the direction Y perpendicular to the medium transport direction X of the attachment portion 412, and away from the lower end surface 22 of the frame 20. A bent contact portion 413 is provided.

  As shown in FIGS. 9A and 9D, the attachment portion 412 extends in the direction Y orthogonal to the medium conveyance direction X, and the end portions on the frame 20 side of the respective spanning portions 411 are continuous. A width portion 412a and a wide portion 412b wider than the constant width portion 412a provided in the middle of the constant width portion 412a are provided. Each of the wide portions 412b is formed with an engagement hole 412c that can engage with the engagement protrusion 27 of the frame 20. As shown in FIGS. 9C and 9D, the conductive member 41 engages the engagement hole 412c with the engagement protrusion 27, melts and crushes the engagement protrusion 27 with heat, and closes the engagement hole 412c. Thus, the lower end surface portion 22a of the frame 20 is attached.

  Here, the conductive member 41 is in a state before being attached to the frame 20, that is, the shape of the conductive member 41 itself is flat except for the contact portions 413 at both ends, but the lower end surface of the frame 20 to which the conductive member 41 is attached. Since the portion 22 a is located above the lower ends of the second protrusion 333 and the fourth protrusion 335 of the core body 33 of the magnetic sensor element 13, the attachment portion 412 of the conductive member 41 is the lower end surface portion 22 a of the frame 20. As shown in FIG. 5, each of the plurality of spanning portions (first spanning portion, second spanning portion) 411 includes a plurality of magnetic sensor elements (first ones) mounted on the frame 20. (1 magnetic sensor element, 2nd magnetic sensor element) 13 and is elastically deformed downward between the frame 20 and the sensor core 32 of each magnetic sensor element 13. That. As a result, the leading end portion 411a of each spanning portion 411 on the sensor core 32 side is pressed against the exposed portion 32a of the fourth protrusion 335 of the sensor core 32 by the elastic restoring force of the spanning portion 411. Thereby, the electrical connection state of the sensor core 32 and the conductive member 41 of the plurality of magnetic sensor elements 13 is formed.

  Here, as shown in FIG. 2, the magnetic sensor device 8 is held by a case 10 on which the first magnetizing magnet 6 and the second magnetizing magnet 7 are mounted, and constitutes the magnetic sensor unit 5. . FIG. 10A is an explanatory diagram of a state where the magnetic sensor device 8 is held by the case 10, and FIG. 10B is a cross-sectional view of a state where the magnetic sensor device 8 is held by the case 10. As shown in FIG. 10B, the case 10 includes a groove 52 into which the magnetic sensor device 8 can be inserted. When the magnetic sensor device 8 is inserted into the groove 52 from above, The contact portion 413 of the conductive member 41 fixed to the end surface portion 22 a comes into contact with the inner peripheral surface portion 52 a of the groove 52. Here, the case 10 is grounded via the frame 20 of the magnetic pattern detection device 1 or the like. Thereby, the sensor core 32 of the magnetic sensor element 13 is grounded via the case 10 and the conductive member 41.

(Method of manufacturing magnetic sensor device)
A method for manufacturing the magnetic sensor device 8 will be described with reference to FIGS. Fig.11 (a) is a front view of the magnetic sensor apparatus 8 before grinding the upper end surface of a magnetic sensor apparatus, FIG.11 (b) is the side view.

  When manufacturing the magnetic sensor device 8, first, each magnetic sensor element 13 is inserted into each mounting hole 23 of the frame 20 (insertion step). Accordingly, each magnetic sensor element 13 abuts on the inner peripheral surface portion 23c of each mounting hole 23 and is orthogonal to the direction of the axis L of the mounting hole 23, that is, orthogonal to the medium transport direction X and the medium transport direction X. Positioning in the direction Y As a result, the positions of the magnetic sensor elements 13 are accurately defined.

  Next, the plurality of magnetic sensor elements 13 inserted into the mounting holes 23 of the frame 20 are supported from below by a single jig (not shown), and the magnetic sensor elements 13 are used with reference to the grinding reference surface 26 of the frame 20. Is positioned in the direction of the axis L of each mounting hole 23 (positioning step). In this example, the positions of the lower end surface 333 a of the second protrusion 333 and the lower end surface 335 a of the fourth protrusion 335 of the core body 33 are predetermined in the direction of the axis L of each mounting hole 23 with respect to the grinding reference surface 26. Positioned to be placed in position.

  When each magnetic sensor element 13 is positioned in the direction of the axis L of the mounting hole 23, the magnetic sensor device 8 has an upper end surface 332 a of the first protrusion 332 of the core body 33 and an upper end surface 334 a of the third protrusion 334. From the upper end opening 23 a of each mounting hole 23, that is, the upper end surface 21 of the frame 20, the mounting hole 23 protrudes upward beyond the thickness dimension of the wear-resistant plate 19 (see FIG. 11B).

  Thereafter, two rectangular wear-resistant plates 19 are inserted inside the flange portion 24 of the frame 20 with a predetermined gap in the medium transport direction X and placed on the upper end surface 21 of the frame 20 ( Wear-resistant plate placement process). Also, resin 29 is filled into each mounting hole 23 through a gap between the two wear-resistant plates 19, whereby each magnetic sensor element 13 and each wear-resistant plate 19 are fixed to the frame 20 ( Fixing process). Here, the resin 29 is filled until it protrudes above the flange portion 24 of the frame 20. This state is the state shown in FIG.

  Thereafter, with reference to the grinding reference surface 26 of the frame 20, the upper end surface 332 a of the first protrusion 332, the upper end surface 334 a of the third protrusion 334, and the upper end surfaces 19 a of the two wear-resistant plates 19. Then, the resin 29 protruding between the two wear-resistant plates 19 is subjected to surface grinding to a preset surface grinding surface B (surface grinding step). By this surface grinding, the upper end surface 332a (sensor surface 13a) of the first protrusion 332 of the core body 33, the upper end surface 334a of the third protrusion 334, the upper end surface 19a of the two wear-resistant plates 19 and the resin 29 Are located on the same plane.

  Next, the conductive member 41 is attached to the lower end surface 22 of the frame 20, and the leading end portion 411 a of the spanning portion 411 of the conductive member 41 is brought into contact with the exposed portion 32 a of the sensor core 32. Thereby, the assembly of the magnetic sensor device 8 is completed.

  After that, the magnetic sensor device 8 is inserted inside the groove 52 of the case 10 so that the contact portion 413 of the conductive member 41 and the inner peripheral surface portion 52a of the groove 52 are in contact with each other. Then, the sensor core 32 of the magnetic sensor element 13 is grounded by grounding the case 10.

(Magnetic pattern detection operation of magnetic pattern detector)
The magnetic pattern detection operation of the magnetic pattern detection apparatus 1 will be described with reference to FIGS. FIG. 12A shows an excitation waveform of the magnetic sensor element 13, and FIG. 12B shows a detection waveform from the magnetic sensor element 13. As shown in FIG. 4, when the medium 2 is transported in the first direction X1 or the second direction X2 in the magnetic pattern detection apparatus 1 in the first direction X1 or the second direction X2, the medium 2 reaches the first position before reaching the magnetic reading position A. Magnetized by the magnet 6 or the second magnet 7. The magnetized medium 2 passes through the magnetic reading position A by the magnetic sensor device 8.

  In the magnetic sensor device 8, as shown in FIG. 12A, an alternating current is applied to the exciting coil 34 at a constant current, and a bias magnetic field indicated by a one-dot chain line in FIG. 8 is formed around the core body 33. Has been. When the medium 2 is conveyed at the magnetic reading position A, the detection coil 35 outputs a signal having a detection waveform shown in FIG. The detected waveform is a differential signal with respect to the bias magnetic field and time.

  Here, the shape, peak value, and bottom value of the detected waveform from the magnetic sensor element 13 are the type of magnetic ink used for forming the magnetic pattern, the position of the magnetic pattern, and the density of the formed magnetic pattern. It depends on. Therefore, by comparing the detected waveform with a reference waveform stored and held in advance, the authenticity of the medium 2 and the type of the medium 2 can be determined.

(Function and effect)
According to this example, the sensor surface 13a of each magnetic sensor element 13 is positioned on the same plane by surface grinding. Further, since the positioning of the magnetic sensor element 13 with respect to the frame 20 is performed based on the grinding reference surface 26 of the frame 20 for surface-grinding the sensor surface 13a, the sensor surface 13a is positioned regardless of the dimensional tolerance of the frame 20. The position is defined at a predetermined position with respect to the grinding reference surface 26 of the frame 20, and the position of the sensor surface 13a with respect to the frame 20 does not vary. Therefore, when the magnetic sensor device 8 is mounted on the magnetic pattern detection device 1, it can be avoided or reduced that the gap between the medium transport surface 11 a and the magnetic sensor element 13 is fluctuated, and the characteristic variation between the magnetic sensor elements 13 can be reduced. Is also reduced.

  In this example, the wear-resistant plate 19 is disposed on the upper end surface 21 of the frame 20, and the sensor surface 13 a is ground with the surface of the wear-resistant plate 19 using the grinding reference surface 26 as a reference. Accordingly, the sensor surface 13a of the magnetic sensor element 13 can be protected by being surrounded by the wear resistant plate 19. Further, since the upper end surface 19a of the wear-resistant plate 19 and the sensor surface 13a of each magnetic sensor element 13 can be positioned on the same plane, the wear-resistant plate 19 can reduce the wear of the sensor surface 13a. it can.

Furthermore, in this example, after the sensor surface 13a of each magnetic sensor element 13 protrudes from the upper end opening 23a of the mounting hole 23 by the thickness dimension of the wear resistant plate 19, the sensor surface 13a is moved to the upper end surface of the wear resistant plate 19. Since the surface grinding is performed together with 19a, the sensor surface 13a can always be exposed after the surface grinding.

  Further, according to this example, the ground wire is not directly soldered to the sensor core 32 but the conductive member 41 is pressed against the magnetic sensor element 13 from the side of the frame 20 holding the magnetic sensor element 13. The conductive member 41 is configured to be grounded on the frame 20 side. Therefore, the sensor core 32 can be grounded regardless of the material forming the sensor core 32.

  That is, the sensor core 32 may be formed of ferrite, silicon steel plate, amorphous, permalloy, etc., but the ferrite does not have solder for connecting the ground wire, and the silicon steel plate generally has an antioxidant film by plating. Because it is formed, it is difficult to attach solder for connecting the ground wire. Amorphous and permalloy have poor solderability, and in order to connect the ground wire, a special device for performing soldering in a deoxygenated atmosphere is required, and workability is lowered. However, according to this example, it is possible to avoid soldering the sensor core 32 with respect to each of these materials when the sensor core 32 is grounded. Therefore, the sensor core 32 can be grounded regardless of the material forming the sensor core 32. Further, since it is possible to avoid exposing the sensor core 32 to high heat at the time of grounding, the sensor core 32 is not caused to change in shape or decrease in magnetic characteristics.

  Further, according to the present example, the spanning portion 411 of the conductive member 41 is elastically deformed between the frame 20 and the sensor core 32, and the tip portion 411a of the spanning portion 411 on the sensor core 32 side is the spanning portion. It is pressed against the sensor core 32 by the elastic return force 411 and pressed against the sensor core 32. Therefore, the contact between the conductive member 41 and the sensor core 32 is reliable, and the contact between the conductive member 41 and the sensor core 32 can be maintained even when the position of the magnetic sensor device 8 on the frame 20 changes.

  Furthermore, according to this example, since the conductive member 41 is a metal spring member, it is easy to elastically deform the spanning portion 411 and press it against the sensor core 32.

  In this example, since the conductive member 41 includes the plurality of spanning portions 411, the plurality of magnetic sensor elements 13 mounted on the frame 20 can be grounded via the single conductive member 41.

  Furthermore, since the conductive member 41 is attached to the frame 20 by engaging the engagement hole 412c of the attachment portion 412 and the engagement protrusion 27 of the frame 20, the attachment work of the conductive member 41 to the frame 20 is easy. It is.

  Further, since the conductive member 41 is pressed against the conductive case 10 covering the outer peripheral surface portion of the frame 20, the sensor core 32 can be grounded by grounding the case 10. Therefore, the workability for grounding the sensor core 32 is good.

(Other embodiments)
In the above example, the wear-resistant plate 19 is placed on the frame 20 after the magnetic sensor element 13 is positioned in the direction of the axis L of the mounting hole 23, but the wear-resistant plate 19 is mounted on the frame 20. After mounting, the magnetic sensor element 13 may be positioned in the direction of the axis L of the mounting hole 23.

  In the above example, the conductive member 41 is made of metal, but the conductive member 41 may be formed of a conductive resin.

1. Magnetic pattern detection device 2. Medium 3. Medium transport path 4. Medium transport mechanism 5. Magnetic sensor unit 6. First magnetizing magnet 7. Second magnetizing magnet 8. 8A · Magnetic sensor device, 8a · Sensor surface, 10 · Case, 11 · Cover plate, 11a · Medium transport surface, 13 · Magnetic sensor element, 13a · Sensor surface, 14 · Front cover plate, 14a · Front surface, 14b · Back surface 15 · back side cover plate, 16 · magnet, 19 · wear resistant plate, 19a · upper end surface, 20 · frame, 21 · upper end surface, 22 · lower end surface, 22a · lower end surface portion, 23 · mounting hole, 23a -Upper end opening, 23b-Lower end opening, 23c-Inner peripheral surface part, 24-Flange part, 25-Projection part, 26-Grinding reference surface, 27-Engagement protrusion, 28-Partial sealing part, 29-Resin, 30- First protective plate, 31 second protective plate, 2. Sensor core, 32a, exposed portion, 33, core body, 34, excitation coil, 35, detection coil, 36, first coil bobbin, 37, second coil bobbin, 38, terminal pin, 39, locking pin, 41, conductive Member, 52 / groove, 52a / inner peripheral surface portion, 101 / upper end surface, 102 / recessed portion, 103 / inclined surface, 111 / opening portion, 141 / opening portion, 151 / opening portion, 152 / first mounting hole, 153・ Second mounting hole, 154, mounting hole, 331, trunk, 332, first protrusion, 332a, upper end surface, 333, second protrusion, 333a, lower end surface, 334, third protrusion, 334a, upper End surface, 335, fourth protrusion, 335a, lower end surface, 411, spanning portion, 411a, tip portion, 412, mounting portion, 412a, constant width portion, 412b, wide portion, 412c, engagement hole, 413, contact Part, A, magnetic reading Taken position, B · surface grinding surface, the axial direction of L · mounting hole, X · medium conveying direction, X1 · first direction, X2 · second direction, a direction perpendicular to the Y · medium conveyance direction

Claims (7)

In a manufacturing method of a multi-channel magnetic sensor device in which a plurality of magnetic sensor elements are mounted on a frame,
A frame preparation step of preparing a frame in which a plurality of parallel mounting holes penetrating from one side to the other side of the frame and a grinding reference surface orthogonal to the axis of each mounting hole are formed as the frame;
An insertion step of inserting each magnetic sensor element into each mounting hole in a state where the sensor surface of each magnetic sensor element faces one side;
A positioning step of positioning the magnetic sensor element in the direction of the axis of the mounting hole with respect to the grinding reference surface, and projecting the sensor surface from a first opening on one side of the mounting hole;
A fixing step of filling each mounting hole with resin and fixing each magnetic sensor element to the frame;
Said sensor surface, seen including a surface grinding step of surface grinding the grinding reference plane as a reference,
And a wear-resistant plate arranging step of arranging a wear-resistant plate on an end surface of the frame where the first opening is exposed between the inserting step and the fixing step,
In the fixing step, the wear-resistant plate is fixed to the frame by the resin,
The frame has a rectangular outline shape when viewed from the direction of the axis of the mounting hole, and is provided with protrusions protruding to the other side at the four corners of the other end surface of the frame. A method of manufacturing a multi-channel magnetic sensor device, wherein the other end surface of the magnetic field sensor is the grinding reference surface . In claim 1,
In the inserting step, the magnetic sensor element is brought into contact with an inner peripheral surface of the mounting hole, and the magnetic sensor element is positioned in a direction perpendicular to the axis of the mounting hole. Manufacturing method. In claim 1 or 2,
In the surface grinding step, the sensor surface is surface ground together with the surface of the wear-resistant plate using the grinding reference surface as a reference, and the method for manufacturing a multi-channel magnetic sensor device. In any one of claims 1 to 3 ,
In the positioning step, the multi-channel magnetic sensor device manufacturing method is characterized in that the sensor surface is protruded from the first opening of the mounting hole by more than the thickness dimension of the wear-resistant plate. In a multi-channel magnetic sensor device in which a plurality of magnetic sensor elements are mounted on a frame,
With wear-resistant plates,
The frame includes a plurality of parallel mounting holes penetrating from one side of the frame to the other side, and a grinding reference surface orthogonal to the axis of each mounting hole,
Each magnetic sensor element is inserted into each mounting hole with the sensor surface facing one side, and positioned so that the sensor surface protrudes from the first opening on one side of the mounting hole with respect to the grinding reference surface. Being fixed to the frame by the resin filled in the mounting hole,
The wear-resistant plate is placed on an end surface of the frame where the first opening is exposed, and is fixed to the frame by the resin,
The contour shape when the frame is viewed from the direction of the axis of the mounting hole is a rectangle,
Projections projecting to the other side are provided at the four corners of the other end face of the frame,
The other end surface of each protrusion is the grinding reference surface,
The multi-channel magnetic sensor device according to claim 1, wherein the sensor surface of each magnetic sensor element is located on the same plane by surface grinding of the sensor surface with reference to the grinding reference surface. In claim 5,
Each of the magnetic sensor elements is positioned in a direction orthogonal to the axis of the mounting hole by contacting the inner peripheral surface portion of each mounting hole. In claim 5 or 6,
The wear-resistant plate and the sensor surface are positioned on the same plane by subjecting the surface of the wear-resistant plate to surface grinding together with the sensor surface on the basis of the grinding reference surface. Channel magnetic sensor device.

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