JP2020198051A - Sensor coil, displacement sensor, and automatic transaction device - Google Patents

Abstract

To reduce variation in distribution of magnetic flux density.SOLUTION: Provided is a sensor coil 50 in which a first coil L1 formed in any layer of a multilayer substrate and a second coil L2 formed coaxially in an adjacent layer are coupled to each other. A centerline C1 of a conductor pattern L1(M) of the first coil L1 is located between a centerline C2 of a conductor pattern L2(M) overlapping in the width direction of the second coil L2 when viewed in the direction of a central axis P of the first coil L1 and the second coil L2 and a centerline C2 of any conductor pattern L2(M-1) adjacent to the second coil L2 in the same layer.SELECTED DRAWING: Figure 7

Description

The present invention relates to a sensor coil, a displacement sensor and an automated teller machine.

Automatic teller machines such as ATMs (Automated Teller Machines) are provided with a thickness sensor that detects the thickness of paper sheets. This thickness sensor includes a reference roller and a detection roller that rotates in accordance with the reference roller, and is configured to electromagnetically detect the vertical movement of the detection roller. As a coil that can be used for a thickness sensor, a detection coil in which windings are formed by a wire pattern of a multilayer substrate is disclosed in Patent Documents 1 and 2.

In particular, Patent Document 2 includes a multilayer substrate, a plurality of lead wire patterns formed in a spiral shape on each of the surface and the interface of the multilayer substrate, and a through hole for electrically connecting the lead wire patterns. A sensor coil is disclosed, characterized in that the multilayer substrate forming the coil and the multilayer substrate forming the second coil are installed in an overlapping manner. Further, Patent Document 2 describes that they are arranged at positions shifted from each other so that the overlapping portions of the lead wire patterns are reduced.

Japanese Unexamined Patent Publication No. 2012-160060 (Summary, paragraphs 0021-0023) Japanese Unexamined Patent Publication No. 2008-58241 (FIGS. 4 (b), 7 (b), paragraphs 0033, 0043).

By the way, in the sensor coil of Reference 2 (FIGS. 4 (b) and 7 (b)), the amount of deviation matches the interval with the adjacent lead wire pattern. Therefore, the magnetic flux generated in the lead wire pattern becomes stronger, but the magnetic flux is not generated between the lead wire pattern and the adjacent lead wire patterns in the same layer, that is, in the region of the pattern interval. That is, in the vicinity of the multilayer substrate, the magnetic flux density obtained by combining the magnetic flux densities generated by the respective lead wire patterns varies.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a coil for a sensor, a displacement sensor, and an automated teller machine capable of reducing variations in magnetic flux density.

In order to achieve the above object, in the present invention, the first coil (L1) formed in any layer of the multilayer substrate and the second coil (L2) formed coaxially in the adjacent layer are connected. The center line (C1) of the lead wire pattern (L1 (M)) of the first coil of the sensor coil (50) is the same when viewed in the axial direction of the first coil and the second coil. The center line (C2) of the lead wire pattern (L2 (M)) of the second coil and the center line (C2) of any of the lead wire patterns (L2 (M-1)) adjacent to the second coil in the same layer. It is characterized by being placed between. The symbols and characters in parentheses are the symbols and the like attached in the embodiments, and do not limit the present invention.

According to the present invention, it is possible to reduce the distribution variation of the magnetic flux density.

It is an external view of the automatic teller machine which is 1st Embodiment of this invention. It is the schematic which shows the inside of the banknote discrimination part. It is a block diagram of the displacement sensor which is 1st Embodiment of this invention. It is the schematic sectional drawing of the coil for a sensor. It is a top view of the coil for a sensor. It is a top view of the 1st layer of a coil for a sensor. It is a top view of the 2nd layer of a coil for a sensor. It is a top view of the 3rd layer of the coil for a sensor. It is a top view of the 4th layer of a coil for a sensor. It is a schematic end view of a coil for a sensor. It is a block diagram of the displacement sensor which is 2nd Embodiment of this invention. It is a block diagram of the displacement sensor which is the 3rd Embodiment of this invention. It is the schematic sectional drawing of the coil for a sensor which is the 1st modification of this invention. It is a schematic plan view of the coil for a sensor which is the 3rd modification of this invention.

Hereinafter, embodiments of the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings. In addition, each figure is only shown schematicly to the extent that the present invention can be fully understood. Further, in each figure, common components and similar components are designated by the same reference numerals, and duplicate description thereof will be omitted.

(First Embodiment)
(Explanation of configuration)
FIG. 1 is an external view of an automated teller machine having a displacement sensor according to the first embodiment of the present invention.
The automatic teller machine 1000 is an ATM including a bill handling unit 200, a control device 300, and an operation unit 3. The bill handling unit 200 includes a bill storage (not shown) and a discrimination transport path 14 (FIG. 2), and has a thickness sensor 120 inside the discrimination transport path 14. The thickness sensor 120 includes a displacement sensor 100 and a reference roller 110. Further, the operation unit 3 is composed of a card deposit / withdrawal port 4, an operation display unit 6, a deposit / withdrawal port 7, a transaction slip port 8, and a numeric keypad 5. The bill handling unit 200 and the control device 300 are housed in the lower part of the main body housing 2. The control device 300 includes a CPU (Central Processing Unit), a ROM (Read On Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), etc., controls each part such as the bill handling unit 200, and controls an OS (Operating). The application program running on System) executes the transaction. The operation display unit 6 is connected to the control device 300 and displays the transaction screen.

In the discrimination transport path 14 (FIG. 2), the transport path 13 and the transport sensor 24, the transport roller 32a, the magnetic sensor 34, the transport roller 32b, the optical sensor 35, and the transport roller are arranged in this order from the front side along the transport path 13. A 32c, a thickness sensor 120, a transfer roller 32d, and a transfer sensor 24 are arranged. The discrimination transport path 14 is provided with transport rollers 41 and 42 before and after the discrimination transport path 14. The transport path 13 includes an upper transport guide 13A and a lower transport guide 13B, and transports the bill BL.

The optical sensor 35 includes a linear light source and a line sensor, and captures a front surface image, a back surface image, and a transmission image of the banknote BL. The magnetic sensor 34 detects the magnetic ink printed to prevent counterfeiting of the bill BL. A plurality of magnetic sensors 34 and thickness sensors 120 are arranged in a direction perpendicular to the transport direction of the bill BL (left-right direction).

The thickness sensor 120 detects the thickness of the banknote BL conveyed between the reference roller 110 and the detection roller 80. The reference roller 110 is attached to the lower transport guide 13B and does not move in the vertical direction. The detection roller 80 is supported so as to be displaceable in the vertical direction with respect to the upper transport guide 13A. The displacement sensor 100 detects the thickness of the bill BL by detecting the displacement of the detection roller 80. As a result, the displacement sensor 100 detects the authenticity of the tape attached to the bill BL, the authenticity of the bill BL, and the heavy running.

(Displacement sensor)
FIG. 3 is a configuration diagram of a displacement sensor according to the first embodiment of the present invention.
The displacement sensor 100 includes a detection roller 80 as a detection object, a detection coil 50, a resonance capacitor 65, an oscillation circuit 60, a frequency counter 70, and a control unit 90. The detection roller 80 is a metal roller such as copper or aluminum, and has high conductivity. The displacement sensor 100 may include a metal plate (not shown) interlocking with the displacement of the detection roller 80, and detect the displacement of the metal plate.

FIG. 4 is a schematic cross-sectional view of the sensor coil.
The detection coil 50 as the sensor coil uses a multilayer substrate (for example, a four-layer substrate) in which insulating layers 52 (52a, 52b, 52c) and conductor layers 51 are alternately laminated. A plurality of detection coils 50 are arranged on the multilayer board in a direction perpendicular to the transport direction of the bill BL (left-right direction). The detection coil 50 is a through hole 53 to which a conducting wire pattern (winding) formed in the conductor layer 51 of each layer is connected. The size of the detection coil 50 and the detection roller 80 is several mm square. The detection coil 50 needs to increase the number of turns to increase the self-inductance L, but is subject to the design rules of the multilayer board, for example, the minimum pattern width and the minimum pattern interval.

5 is a plan view of the sensor coil, and FIGS. 6A to 6D are plan views of the first layer to the fourth layer. The right figure of FIG. 5 is a partially enlarged view of a part (right end portion) of the left figure. Further, in FIG. 5, the insulating layer 52 and the through hole 53 are omitted. In FIG. 5, for convenience of explanation, the first layer lead wire pattern L1 is drawn with a solid line, the second layer lead wire pattern L2 is drawn with a broken line, the third layer lead wire pattern L3 is drawn with a dashed line, and the fourth layer lead wire is drawn. The pattern L4 is drawn with a long chain line.

As shown in FIG. 5, the detection coil 50 is formed in a thunder pattern (lightning pattern) whose size decreases from the outer circumference to the inner circumference. The lead wire patterns L1, L2, L3, and L4 are coaxial and have the same central axes P. Further, the lead wire patterns L1, L2, L3, and L4 are not formed in the vicinity (central portion) of the central axis P of the detection coil 50. The lead wire patterns L1, L2, L3, and L4 absorb and reflect the magnetic field with a lead wire pattern other than the current element Idl (not shown) that generates the magnetic field dH (not shown), but absorb and reflect the magnetic field at least in the central part. This is to prevent reflection. As shown in FIG. 7, the detection roller 80 is arranged on the fourth layer side on the central axis P.

Incidentally, the magnetic field H (z) on the central axis of the rectangular coil having two side lengths 2a and 2b through which the current I flows and at the point z from the center is
H (z) = Iab / (2π√ (a ² + b ² + z ² )) · (1 / (a ² + b ² ) + 1 / (b ² + z ² ))
Is. Especially in the square of a = b = l
H (z) = 2Il ² / (π (l ² + z ² ) √ (2l ² + z ² ))
Is. The magnetic field of the detection coil 50 is substantially equal to the superposition of the rectangular coils having different lengths 2a and 2b on both sides.

FIG. 7 is a schematic end view of the sensor coil.
In the lead wire patterns L1, L2, L3, and L4, the pattern width D1 and the pattern interval D2 are set to be equal (D1 = D2). The printed circuit board design rule is that the minimum pattern width and the minimum pattern interval are equal. It is preferable that the pattern width D1 = the minimum pattern width and the pattern interval D2 = the minimum pattern interval. As a result, the detection coil 50 has a close-packed pattern, and the number of turns can be maximized while securing the area at the center.

In the detection coil 50, the lead wire patterns L1, L2, L3, and L4 are connected so that the magnetic field is strengthened, that is, the currents are in the same direction. Here, the outermost peripheral (first circumference) lead wire patterns L1 (1), L2 (1), L3 (1), L4 (1) and the innermost inner circumference (Z (for example, Z = 4) circumference) lead wires. Between the patterns L1 (Z), L2 (Z), L3 (Z), L4 (Z), the lead wire patterns L1 (M-1), L2 (M-1), L3 (M-1), L4 (M-1), lead wire patterns L1 (M), L2 (M), L3 (M), L4 (M), lead wire patterns L1 (M + 1), L2 (M + 1), L3 (M + 1), L4 (M + 1) It is formed.

6A to 6D, the first layer lead pattern L1 (L1 (1), L1 (2), L1 (3), L1 (4)) and the second layer lead pattern L2 (L2 (1), L2 (2), L1 (3), L2 (4)), the third layer lead wire pattern L3 (L3 (1), L3 (2), L3 (3), L3 (4)), and the fourth layer. The lead wire pattern L4 (L4 (1), L4 (2), L4 (3), L4 (4)) is formed in a thunder pattern (lightning pattern) whose size decreases from the outer circumference to the inner circumference. Has been done.

Further, in the detection coil 50, the lead wire patterns L1, L2, L3 and L4 are connected in series by a through hole 53 (FIG. 4). That is, between the tip S1 (FIG. 6A) and the end E4 (FIG. 6D) of the detection coil 50, the end E1 (FIG. 6A) of the first layer lead wire pattern L1 and the tip S2 of the second layer lead pattern L2. (FIG. 6B) is connected, the end E2 of the second layer lead wire pattern L2 and the tip S3 (FIG. 6C) of the third layer lead pattern L3 are connected, and the end E3 of the third layer lead pattern L3 is connected. It is connected to the tip S4 (FIG. 6D) of the lead wire pattern L4 of the fourth layer.

Further, the lead wire patterns L1, L2, L3, and L4 are displaced inward in the order of the lead wire pattern L1 of the first layer, the lead wire pattern L2 of the second layer, the lead wire pattern L3 of the third layer, and the lead wire pattern L4 of the fourth layer. There is. That is, the center lines C1, C2, C3, and C4 of the lead wire patterns L1, L2, L3, and L4 are displaced. The amount of this deviation is D1 / 3. That is, in the case of the N-layer substrate, the amount of deviation is D1 / (N-1). Since D1 = D2, the amount of deviation is also D2 / (N-1).

Therefore, for example, the center line C1 of the wire pattern L1 (M) on the Mth circumference of the wire pattern L1 of the first layer is the same layer as the center line C2 of the adjacent wire pattern L2 (M) of the second layer. (2nd layer) is arranged between the center line C2 of one of the two adjacent wire patterns L2 (M-1) and L2 (M + 1) (specifically, the wire pattern L2 (M-1)). doing.

Further, the lead wire pattern L1 (M) and the lead wire pattern L2 (M) of the adjacent layer are superimposed when viewed from the direction of the central axis P, that is, in a plan view. That is, the center line C1 of the lead wire pattern L1 (M) on the Mth circumference of the lead wire pattern L1 of the first layer is an adjacent second layer and is the same layer as the center line C2 of the superposed lead wire pattern L2 (M). Arranged between the lead wire pattern L2 (M-1) and the lead wire pattern L2 (M + 1) of the second layer adjacent to each other (specifically, the lead wire pattern L2 (M-1)) with the center line C2. doing.

Further, the wire pattern L2 (M) and the wire pattern L3 (M) are superimposed, and the wire pattern L3 (M) and the wire pattern L4 (M) are superposed. However, the lead wire pattern L4 (M-1) and the lead wire pattern L1 (M) are adjacent to each other without overlapping when viewed from the direction of the central axis P. Similarly, the lead wire pattern L4 (M + 1) and the lead wire pattern L1 (M) are adjacent to each other without overlapping when viewed from the direction of the central axis P.

Returning to the explanation of FIG. 3, the oscillation circuit 60 uses a series circuit of the self-inductance L detection coil 50 and the resonance capacitor 65 of the capacitance C at a predetermined reference angular frequency ω0 = 1 / √ (LC). It oscillates. As a result, a resonance voltage V is generated in the series circuit of the detection coil 50 and the resonance capacitor 65, and the resonance current I1 flows. Although the resonance capacitor 65 is connected in series with the detection coil 50, it may be connected in parallel.

Here, when the detection coil 50 and the detection roller 80 are close to each other, an eddy current I2 flows through the detection roller 80, and the resonance current I1 and the eddy current I2 are coupled by a mutual inductance M. In other words, the leakage inductance Le is generated, and the resonance angular frequency ω deviates from the reference angular frequency ω0. That is, when the distance between the detection roller 80 and the detection coil 50 changes, the mutual inductance M and the leakage inductance Le change, so that the resonance angular frequency ω changes.

The frequency counter 70 measures the oscillation frequency f = ω / (2π) of the oscillation circuit 60. The control unit 90 is a CPU, and calculates the displacement amount of the detection roller 80 by using the change amount of the oscillation frequency f measured by the frequency counter 70. As a result, the thickness of the bill BL can be detected, and the control unit 90 can determine the authenticity of the bill BL and the sticking of the tape. The displacement sensor 100 may measure the oscillation frequency f by the control unit 90 without providing the frequency counter 70.

As described above, in the detection coil 50 of the displacement sensor 100 of the present embodiment, the center lines C1, C2, C3 and C4 of the lead wire patterns L1, L2, L3 and L4 are displaced. Therefore, the magnetic flux distribution generated by the lead wire patterns L1, L2, L3, and L4 is more uniform than the magnetic flux distribution when the center lines C1, C2, C3, and C4 overlap.

Further, if the pattern accuracy of the multilayer board is poor and the position is deviated by the same degree as the minimum pattern width or the minimum pattern interval, the center position of the magnetic flux distribution is also deviated. Since the size of the detection roller 80 of the present embodiment is several mm square, the influence of the minimum pattern width and the minimum pattern interval (for example, 100 μm, 127 μm) of the multilayer board is large.

(Comparative Example 1)
In the detection coil 50 of the first embodiment, the lead wire patterns L1, L2, L3, and L4 are shifted from each other in a plan view and overlapped so as not to have a gap. However, the sensor coil described in Patent Document 2 has. , The distance between the same layer and the adjacent wire pattern is shifted. That is, the center line of the conductor pattern of the sensor coil described in Patent Document 2 is an adjacent layer and coincides with the center line of the conductor pattern on the other circumference. Therefore, the magnetic flux generated in the lead wire pattern becomes stronger, but no magnetic flux is generated between the lead wire pattern and the lead wire pattern. That is, there is a distribution variation in the combined magnetic flux density. In other words, in the sensor coil described in Patent Document 2, the central axis of the lead wire pattern of any layer and the central axis of the lead wire pattern of the adjacent layer do not match, so that the sum of the combined magnetic flux densities is the lead wire of any layer. It is not the sum of the maximum magnetic flux density of the pattern and the maximum magnetic flux density of the lead wire pattern of the adjacent layer. This tends to be a problem when the size of the object to be detected is small.

On the other hand, in the detection coil 50 of the first embodiment, since the center lines C1, C2, C3, and C4 of the lead wire patterns L1, L2, L3, and L4 are deviated, the distribution of the combined magnetic flux density varies. Few. Further, since the central axes P of the lead wire patterns L1, L2, L3, and L4 match, the combined magnetic flux density at the central axis P is the sum of the magnetic flux densities at the central axes P of the lead wire patterns L1, L2, L3, and L4. become. That is, since the detection coil 50 has a uniform magnetic flux density, the detection target may be small.

(Comparative Example 2)
The detection coil 50 of the first embodiment has windings formed on a multilayer substrate, but is a columnar coil (square columnar coil or columnar coil) (not shown) in which a lead wire is wound a plurality of times. You can also do it. Since the columnar coil can be made longer in the axial direction than the multilayer substrate, the number of turns can be increased and the sensor sensitivity can be increased.

Since the detection coil 50 of the first embodiment is formed on a thin multilayer substrate with respect to the columnar coil, the winding density is limited by the design rule of the printed circuit board. That is, the detection coil 50 has a smaller self-inductance than the columnar coil, and the detection sensitivity is reduced. Therefore, in order to increase the number of turns, the detection coil 50 sets the pattern width D1 of the lead wire patterns L1, L2, L3, and L4 to the minimum pattern width, and sets the pattern interval D2 to the minimum pattern interval. In general, the minimum pattern width and the minimum pattern interval are equal, so the detection coil 50 is set to D1 = D2.

(Second Embodiment)
Although the displacement sensor 100 of the first embodiment detects a change in frequency, it can also detect a change in voltage amplitude or current amplitude.

FIG. 8 is a configuration diagram of a displacement sensor according to a second embodiment of the present invention.
The displacement sensor 101 includes a detection roller 80, a detection coil 50, a resonance capacitor 65, an oscillation circuit 60, an A / D conversion unit 75, and a control unit 90. The oscillation circuit 60 includes a voltage / current sensor. Has 61.

The oscillation circuit 60 oscillates using a series circuit of the detection coil 50 and the resonance capacitor 65 as in the first embodiment. When the voltage across the series circuit is the resonance voltage V and the current is the resonance current I1, when the position of the detection roller 80 changes, the magnitude of the eddy current I2 changes and the equivalent resistance r changes. In addition, the leakage inductance Le also changes as in the first embodiment. That is, a part of the magnetic flux due to the resonance current I1 is canceled by the magnetic flux due to the eddy current I2.

As a result, the equivalent impedance of the series circuit of the detection coil 50 and the resonance capacitor 65 changes due to the position change of the detection roller 80. Therefore, in the oscillation circuit 60, the amplitude | I1 | of the resonance current I1 changes. If the oscillation circuit 60 is oscillated using a parallel circuit of the detection coil 50 and the resonance capacitor 65, the amplitude | V | of the resonance voltage V changes. Further, since the oscillation circuit 60 oscillates while satisfying the amplitude condition, the other of the amplitude | V | of the resonance voltage V and the amplitude | I1 | of the resonance current I1 also changes. The voltage-current sensor 61 detects the resonance voltage V or the resonance current I1.

The A / D conversion unit 75 A / D-converts the magnitude | V | of the resonance voltage V of the oscillation circuit 60 and the magnitude | I1 | of the resonance current I1. The control unit 90 calculates the change in the magnitude | V | of the resonance voltage V and the change in the magnitude | I1 | of the resonance current I1 using the conversion result of the A / D conversion unit 75, and positions the detection roller 80. Calculate the change.

Since the detection coil 50 has a smaller number of turns than the columnar coil, its self-inductance is smaller than that of the columnar coil. Therefore, in the displacement sensor 101, the change in the magnitude | V | of the resonance voltage V and the change in the magnitude | I1 | of the resonance current I1 become small. On the other hand, since the displacement sensor 100 of the first embodiment measures the frequency, even if the change in the magnitude | V | of the resonance voltage V or the change in the magnitude | I1 | of the resonance current I1 is small, Less affected by noise.

(Third Embodiment)
In the first and second embodiments, the series circuit of the detection coil 50 and the resonance capacitor 65 is oscillated, but a predetermined high frequency voltage V may be applied to the detection coil 50 to detect the current I1. ..

FIG. 9 is a configuration diagram of a displacement sensor according to a third embodiment of the present invention.
The displacement sensor 102 includes a detection roller 80, a detection coil 50, a high frequency power supply circuit 66, an A / D conversion unit 75, and a control unit 90, and the high frequency power supply circuit 66 has a voltage / current sensor 61.
The high-frequency power supply circuit 66 is a high-frequency voltage source that applies a predetermined high-frequency voltage V to the detection coil 50 to supply high-frequency power. As a result, the high frequency current I1 flows through the detection coil 50. Similar to the second embodiment, the equivalent resistance r and the leakage inductance Le due to the eddy current I2 change. That is, since the equivalent impedance of the detection coil 50 changes, the high frequency current I1 changes.

The A / D conversion unit 75 A / D-converts the amplitude | I1 | of the high-frequency current I1. The control unit 90 calculates the change in the amplitude | I1 | of the high-frequency current I1 using the conversion result of the A / D conversion unit 75, and calculates the position change of the detection roller 80. In the high frequency power supply circuit 66, instead of applying the high frequency voltage V to the detection coil 50, the high frequency current I1 may be passed through the detection coil 50, and the voltage / current sensor 61 may detect the high frequency voltage V.

(First modification)
FIG. 10 shows a cross-sectional view of the sensor coil which is the first modification of the present invention, and the shift amount is D1 / 2.
Similar to the above embodiment, the lead wire pattern L1 (M) and the lead wire pattern L2 (M) are superimposed, and the lead wire pattern L2 (M) and the lead wire pattern L3 (M) are overlapped with the lead wire pattern L3 (M). The lead wire pattern L4 (M) is superimposed. Further, the lead wire pattern L4 (M-1) and the lead wire pattern L1 (M) are superposed, and the lead wire pattern L4 (M + 1) and the lead wire pattern L1 (M) are superposed.

(Second modification)
Further, although the plan view is omitted, in the schematic end view of FIG. 7, the lead wire patterns (L1 (1), L2 (1), L3 (1), L4 (1)) on the outermost circumference (first circumference) are shown. The lead wire pattern of the second circumference (L1 (2), L2 (2), L3 (2), L4 (2)) and ..., The lead wire pattern of the Mth circumference (L1 (M), L2 (M), L3 (M), L4 (M)) and ..., the innermost (Zth) lead wire pattern (L1 (Z), L2 (Z), L3 (Z), L4 (Z)) It is assumed that each is formed in a rectangular shape (for example, a square shape) in which a part is cut off.

Here, the outermost peripheral (first round) lead wire pattern (L1 (1), L2 (1), L3 (1), L4 (1)) is connected in series by a through hole 53, and the second round lead wire pattern (L1 (1), L2 (1), L3 (1), L4 (1)) is connected in series. L1 (2), L2 (2), L3 (2), L4 (2)) are connected in series by a through hole 53, and the lead wire pattern (L1 (M), L2 (M), L3 (M) of the Mth circumference is connected. , L4 (M)) are connected in series by a through hole 53, and the innermost (Zth) lead wire pattern (L1 (Z), L2 (Z), L3 (Z), L4 (Z)) is through-hole. It may be connected in series with 53, and these Z coils may be further connected in series. At this time, the lead wire pattern of the detection coil 50 is formed as a lightning pattern (lightning pattern) in which the size decreases from the outer circumference to the inner circumference as a whole.

(Third modification example)
FIG. 11 is a plan view of a sensor coil which is a third modification of the present invention.
The detection coil of each of the above-described embodiments has a thunder-patterned wire pattern, but a spiral-shaped wire pattern can also be used. The detection coil 10 of FIG. 10 forms a lead wire pattern on the multilayer substrate in which the distance a from the central axis P changes according to the angle. The detection coil 10 is formed by shifting the center line of the lead wire pattern in the adjacent layer, similarly to the detection coil 50 of the first embodiment.

Incidentally, the magnetic field H (z) on the central axis of the circular coil having the radius a through which the current I flows and at the point z from the center is
H (z) = a ² I / (2 (a ² + z ² ) ^3/2 ) [A / m]
Is. The magnetic field of the detection coil 10 is substantially equal to the superposition of circular coils with different radii a.

10 Detection coil 13 Transport path 14 Discrimination transport path 50 Detection coil (sensor coil)
60 Oscillator 61 Current sensor 65 Resonant capacitor 66 High frequency power supply circuit 70 Frequency counter 75 A / D converter (amplitude converter)
80 Detection roller 90 Control unit 100, 101, 102 Displacement sensor 110 Reference roller 120 Thickness sensor 200 Banknote handling unit 300 Control device 1000 Automatic teller machine P Central axis L1, L2, L3, L4 Lead wire pattern C1, C2, C3, C4 Center line

Claims (10)

A sensor coil in which a first coil formed on any layer of a multilayer board and a second coil coaxially formed on an adjacent layer are connected.
The center line of the lead wire pattern of the first coil is adjacent to the center line of the lead wire pattern of the second coil in the same layer as the second coil when viewed in the axial direction of the first coil and the second coil. A coil for a sensor, characterized in that it is arranged between the center line of any of the lead wire patterns. The sensor coil according to claim 1.
One of the wire pattern of the first coil and the wire pattern of the second coil is characterized in that a part of the width direction overlaps when viewed in the axial direction of the first coil and the second coil. Coil for the sensor. The sensor coil according to claim 1.
A coil for a sensor, characterized in that the width of the lead wire pattern and the distance between adjacent lead wire patterns in the same layer are substantially equal. The sensor coil according to claim 3.
The multilayer board is an N (N is a natural number of 3 or more) layer board.
For a sensor, (N-1) times the distance between the center line of the lead wire pattern of the first coil and the center line of the lead wire pattern of the second coil is substantially equal to the width or spacing of the lead wire pattern. coil. The sensor coil according to claim 1.
The width of the lead pattern is approximately equal for each layer,
The side edge portion of the lead wire pattern of the first coil is the same layer as the side edge portion of the lead wire pattern of the second coil when viewed in the axial direction of the first coil and the second coil. A sensor coil characterized by being placed between the side edges. The sensor coil according to any one of claims 1 to 5.
The first coil and the second coil are sensor coils characterized in that they are formed in a spiral shape or a thunder pattern. A displacement sensor that detects the displacement of metal
The sensor coil placed close to the metal and
A resonance capacitor connected in series or in parallel with the sensor coil,
An oscillation circuit that oscillates using a combination circuit of the sensor coil and the resonance capacitor,
It is provided with a frequency counter for detecting the frequency of the high frequency current flowing through the sensor coil or the high frequency voltage applied to the sensor coil.
The sensor coil is connected to a first coil formed on any layer of a multilayer substrate and a second coil coaxially formed on an adjacent layer.
The center line of the lead wire pattern of the first coil is adjacent to the center line of the lead wire pattern of the second coil in the same layer as the second coil when viewed in the axial direction of the first coil and the second coil. A displacement sensor characterized in that it is placed between the center line of the lead wire pattern. A displacement sensor that detects the displacement of metal
The sensor coil placed close to the metal and
A resonance capacitor connected in series or in parallel with the sensor coil,
An oscillation circuit that oscillates using a combination circuit of the sensor coil and the resonance capacitor,
A voltage-current sensor that detects a high-frequency current flowing through the sensor coil or a high-frequency voltage applied to the sensor coil is provided.
The sensor coil is connected to a first coil formed on any layer of a multilayer substrate and a second coil coaxially formed on an adjacent layer.
The center line of the lead wire pattern of the first coil is adjacent to the center line of the lead wire pattern of the second coil in the same layer as the second coil when viewed in the axial direction of the first coil and the second coil. A displacement sensor characterized in that it is placed between the center line of the conducting wire pattern. A displacement sensor that detects the displacement of metal
The sensor coil placed close to the metal and
A high-frequency power supply that supplies high-frequency power to the sensor coil,
A voltage-current sensor that detects a high-frequency current flowing through the sensor coil or a high-frequency voltage applied to the sensor coil is provided.
The sensor coil is connected to a first coil formed on any layer of a multilayer substrate and a second coil coaxially formed on an adjacent layer.
The center line of the lead wire pattern of the first coil is adjacent to the center line of the lead wire pattern of the second coil in the same layer as the second coil when viewed in the axial direction of the first coil and the second coil. A displacement sensor characterized in that it is placed between the center line of the conducting wire pattern. An automated teller machine having a thickness sensor that detects the thickness of paper sheets inserted between the reference roller and the detection roller.
The thickness sensor has a sensor coil in which a first coil formed on any layer of a multilayer substrate and a second coil coaxially formed on an adjacent layer are connected.
The sensor coil is arranged close to the detection roller.
The center line of the lead wire pattern of the first coil is adjacent to the center line of the lead wire pattern of the second coil in the same layer as the second coil when viewed in the axial direction of the first coil and the second coil. An automated teller machine characterized in that it is placed between the center line of the lead wire pattern.

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