Planar coil arrangement and displacement sensor

Abstract

The purpose of the present invention is to provide a planar coil assembly with a simplified structure for electrically connecting a plurality of planar coils and also having the function of a low-loss electrical signal path. The planar coil assembly (AR) comprises: a first planar coil (SU1) having a first spiral shape in which a first conductor is wound counterclockwise or clockwise with respect to a first core; and a second planar coil (SU2) having a second spiral shape in which a second conductor, located in the same layer as the first conductor, is wound with respect to a second core using the same winding as for the first planar coil and in which there is an angular deviation from the first spiral shape.

Description

TECHNICAL FIELD

[0001] The present invention relates to a planar coil assembly, a displacement sensor or the like. State of the art

[0002] Fig. 1 of Patent Literature Document 1 shows a planar coil assembly including a plurality of coils, and Fig. Figure 5 shows a current flow in each planar coil.

[0003] Paragraph

[0027] of this literature document describes that "currents with opposite rotation directions flow in the two coil sections L1a and L1b of the coil L1." In other words, the two adjacent coil sections have opposite spiral winding directions.

[0004] As from Fig. As can be seen in Figure 5, when a current flows from a terminal on an outer peripheral side of a spiral to a center of the spiral in one coil, a current also flows in the other coil in the same direction. In other words, the current flows in the same direction.

[0005] Patent Literature Document 2 describes a stroke sensor applicable to a vehicle such as a motorcycle.

[0006] Fig. 9 and Fig. 10 of Patent Literature Document 2 shows a stroke sensor that detects a change in a frequency of an alternating current (AC) signal flowing through a coil according to a change in a length of overlap between a movable conductor and the coil, that is, a change in a fitting length, and detects a stroke amount. CITATION LISTPATENT LITERATURE Patent Literature Document 1: WO2020 / 035968 Patent Literature Document 2: JP6450611B SUMMARY OF THE INVENTION TECHNICAL PROBLEM

[0007] Studies by the present inventors have revealed the following problems. In Patent Literature 1, a wiring configuration connecting each planar coil is complicated, and the planar coil array is inevitably enlarged.

[0008] Furthermore, in Patent Literature 1, a plurality of coils can be combined to form a coil with a large number of turns. However, an electrical signal cannot be transmitted through each coil. In other words, since a path for the electrical signal cannot be formed, it is difficult to apply the planar coil arrangement to an application for detecting electrical characteristics of the electrical signal, such as a stroke sensor.

[0009] Furthermore, the production of the coil adapted to the cylindrical conductor described in Patent Literature 2 requires time and cost.

[0010] An object of the present invention is to provide a planar coil assembly whose configuration is simplified and which can be used as a path of an electrical signal.

[0011] Another object of the present invention is to provide a displacement sensor capable of reducing man-hours and costs during manufacturing. SOLUTION TO THE PROBLEM

[0012] As a result of intensive studies, the present inventors have found that the above problem can be solved by designing the shape of each spiral of two planar coils arranged adjacent to each other.

[0013] The present invention has been completed based on these findings. The present disclosure will be described below.

[0014] According to one aspect of the present disclosure, a planar coil assembly (AR) is provided, comprising: a first planar coil (SU1) having a first spiral shape in which a first conductor (310) is wound left-handed or right-handed around a first center (50); and a second planar coil (SU2) having a second spiral shape in which a second conductor (314) is wound on the same layer as the first conductor (SU1) in the same manner as the first planar coil around a second center (50) and has an angular deviation from the first spiral shape.

[0015] In a preferred example, the angular deviation may be a deviation of 180 degrees.

[0016] According to another aspect of the present disclosure, there is provided a planar coil assembly (AR) comprising: a plurality of the above planar coil assemblies (AR-1 to AR-3), wherein the planar coil assemblies (AR-1 to AR-3) extend parallel to each other along a predetermined direction and are stacked at intervals in a direction orthogonal to the predetermined direction.

[0017] Here the interval is not limited in size and can be an object with an insulator placed in between, as long as isolation is ensured.

[0018] According to yet another aspect of the present disclosure, there is provided a displacement sensor (150) comprising: the above planar coil assembly (AR); and a detection unit (7) configured to detect a change in electrical characteristics of an electrical signal generated according to a displacement amount of a movable conductive object (M1) and transmitted via the planar coil assembly. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0019] According to the present invention, the planar coil assembly can be provided which is simplified in configuration and usable as a path of an electric signal.

[0020] According to the present invention, the planar coil assembly capable of generating a strong magnetic field can be provided.

[0021] Furthermore, according to the present invention, the displacement sensor capable of reducing man-hours and costs during manufacturing can be provided. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing an overall configuration and an equivalent circuit of a planar coil assembly according to Embodiment 1. Fig. Figure 2 is a diagram showing an arrangement of two planar coils arranged in Fig. 1 are arranged adjacent to each other, showing directions of flowing currents and an electrical connection. Fig. 3 is a diagram showing another example of the arrangement of the two planar coils arranged adjacent to each other, the directions of the flowing currents, and the electrical connection. Fig. Figure 4 is a diagram showing another example of the electrical connection between the two planar coils used in Fig. 2 are arranged adjacent to each other. Fig. 5 is a diagram showing an example of an arrangement of a planar coil assembly having a multi-layer structure using four planar coils, a current flow, and an electrical connection. Fig. 6A is a diagram showing a configuration in which a movable conductor is arranged near a planar coil assembly having a multilayer structure using eight planar coils. Fig. Figure 6B is a cross-sectional view of the planar coil assembly and the movable conductor in Fig. 6A. Fig. 7 is a cross-sectional view of a structure in which shielding members for shielding a magnetic field are provided between the planar coil assembly and an object to be protected arranged around the planar coil assembly. Fig. 8 is a diagram showing a configuration in which a magnetic shielding member functions as a yoke as a component of the magnetic circuit. Fig. 9 is a diagram showing an example of an undesirable effect due to the planar coil assembly acting as a transmission path of an AC signal. Fig. 10 is a diagram showing an example of a configuration of shielding elements for suppressing the Fig. 9 shows undesirable effects. Fig. 11 is a view showing a relative positional relationship between the shielding members and a Fig. 10 shows the planar coil arrangement. Fig. 12 is a diagram showing another configuration example of the magnetic shielding elements. Fig. 13 is a diagram showing yet another configuration example of the magnetic shielding elements. Fig. 14 is a diagram showing a configuration using a comb-tooth-shaped movable conductor and a plurality of planar coil assemblies. Fig. 15 is a diagram showing an arrangement example of the magnetic shielding elements. Fig. 16 is a diagram showing a structural example of a planar coil assembly having a three-dimensional shape and a direction of a generated magnetic field. Fig. Figure 17 is a diagram showing another structural example of the planar coil array with the three-dimensional shape and the direction of the generated magnetic field. Fig. 18 is a diagram showing a detection principle of a displacement sensor. Fig. 19A is a diagram showing an example of a specific configuration of the displacement sensor. Fig. 19B is a diagram showing an example of a change in a frequency of a current pulse signal according to a change in a fitting length between the movable conductor and a coil. Fig. 20 is a diagram showing an example of an overall configuration of a motorcycle in which the displacement sensor of the present invention is applied to a suspension. Fig. 21 is a cross-sectional view showing an example of a sectional structure of a Fig. 20 shows the rear suspension. Fig. 22 is a diagram showing an example of a prior art planar coil extending in one direction. Fig. 23 is a diagram showing a configuration example of a planar coil arrangement in a comparative example. DESCRIPTION OF EMBODIMENTS

[0022] Embodiments of the present invention will be described below with reference to the accompanying drawings. The embodiments shown in the accompanying drawings are examples of the present invention, and the present invention is not limited to the embodiments. <Ausführungsform 1>

[0023] It will be Fig. 1 reference is made. Fig. 1 is a diagram showing an overall configuration and an equivalent circuit of a planar coil assembly according to Embodiment 1.

[0024] In Fig. 1, an X direction can be referred to as a horizontal direction or a left-right direction, a Y direction can be referred to as a width direction, and a Z direction can be referred to as a height direction or a top-bottom direction. A +X direction can be referred to as a right direction, a -X direction can be referred to as a left direction, a +Y direction can be referred to as a positive width direction, a -Y direction can be referred to as a negative width direction, a +Z direction can be referred to as an upper direction, and a -Z direction can be referred to as a lower direction. This also applies to the subsequent drawings.

[0025] In the following description, a term “planar coil” is mainly used, and this term may be replaced by a term “planar coil unit”.

[0026] In the following description, a term "right-handed" or "left-handed" may be used in reference to the shape of a spiral. A case where a conductor is wound clockwise with respect to a center of the spiral, in other words, a center of the planar coil, is called right-handed. A case where the conductor is wound counterclockwise with respect to the center of the spiral, in other words, the center of the planar coil, is called left-handed.

[0027] Further, a direction of a current flowing in the spiral includes a first direction in which a current flows from the center of the spiral to an end portion on an outer peripheral side, and a second direction in which a current flows from the end portion on the outer peripheral side to the center of the spiral.

[0028] For example, if current flows in the first direction in a left-handed spiral, the current's rotation direction is counterclockwise, which is the same as the spiral's winding direction. On the other hand, if current flows in the second direction, the current's rotation direction is clockwise, which is opposite to the spiral's winding direction.

[0029] It is necessary to distinguish the spiral winding direction from the direction of rotation of the current flowing in the spiral. The direction of rotation of the current can be reformulated as a direction of circulation of the current.

[0030] An upper side of Fig. Figure 1 shows a relative positional relationship between a movable conductor and a coil in a stroke sensor as a displacement sensor. The stroke sensor will be described in detail later.

[0031] A coil CL1 extends long along the horizontal direction and has a length LQ in the horizontal direction. Here, a moving object M1 is represented as a cylindrical conductor.

[0032] The object M1 is fitted to the coil CL1 with a fitting length LT. When the object M1 is displaced in a direction of a central axis of the cylinder, in other words, in the horizontal direction, the fitting length LT fluctuates, and accordingly, a leakage current fluctuates, and the inductance of the coil CL1 varies. Due to the variation in inductance, a resonant frequency of an oscillator (not shown) connected to the coil CL1 changes. For example, a current pulse signal whose frequency changes can be obtained according to a change in the oscillation frequency.

[0033] In Fig. 1, for simplicity, conductor M1 moves, but coil CL1 can move. In other words, a relative positional relationship between conductor M1 and coil CL1 changes.

[0034] It is difficult to implement the coil CL1 by a planar coil. Here, Fig. 22 is referred to. Fig. Fig. 22 is a diagram showing an example of a planar coil in the prior art that extends in one direction. In a planar coil 250, which is Fig. As shown in Figure 22, a length in a longitudinal direction is Wx and a length in a width direction is Wy. When the number of turns is increased, since the length in the width direction is short, this part limits the number of turns. Accordingly, it is difficult to prepare a coil that generates a strong magnetic field.

[0035] Thus, in the present invention, a coil extending along a predetermined direction is implemented using a planar coil assembly comprising a plurality of planar coils.

[0036] With further reference to Fig. 1 the description continues. As in a middle of Fig. 1, the coil CL1 can be implemented, for example, by a planar coil array AR, which is implemented by connecting four planar coils in series between power supply terminals A and B.

[0037] The planar coil arrangement AR can be implemented by arranging two types of planar coils SU1 and SU2 along the right direction, which is a predetermined direction, and electrically connecting the planar coils, in other words, in series.

[0038] The planar coil array AR has both a function as coils for generating a magnetic field and a function as a path of an electrical signal for transmitting the electrical signal via the coils, in other words, a transmission path. A direction of the current in the planar coil array AR, which is located in the center of Fig. 1 is indicated by white arrows.

[0039] The planar coil SU1 is arranged at a left end of the planar coil array AR, the planar coil SU2 is arranged adjacent to the planar coil SU1 in the right direction, the planar coil SU1 is arranged adjacent to the planar coil SU2 in the right direction, and the planar coil SU2 is arranged adjacent to the planar coil SU1 in the right direction.

[0040] The planar coil array AR extends along the horizontal direction, which is a predetermined direction, and functions as a coil that is long in the horizontal direction as a whole. Note that an arrangement direction of each planar coil is desirably linear, but the arrangement direction is not limited thereto, and a zigzag arrangement may be allowed to some extent.

[0041] The planar coil SU1 has a left-handed spiral shape with respect to the center of the coil, and the number of turns is three, in other words, three turns. However, the present invention is not limited to this.

[0042] The planar coil SU2 has a left-handed spiral shape with respect to the center of the coil, and the number of turns is three, in other words, three turns. The planar coil SU2 is similar to the planar coil SU1 in this respect, but the planar coil SU2 has a spiral shape with a deviation of 180 degrees from the spiral of the planar coil SU1.

[0043] Here, the 180 degree deviated spiral means that in other words, one phase of the spiral deviates by 180 degrees, in other words, means a relative positional relationship in which when a spiral is rotated left or right by 180 degrees, one spiral overlaps the other spiral.

[0044] The spirals in which the spiral directions are opposite to each other, in other words, the right-handed and left-handed spirals, are in a relative positional relationship in which, when one spiral is reversed horizontally, one spiral overlaps the other spiral, the relative positional relationship being different from the relative positional relationship in which the phase deviates by 180 degrees.

[0045] Further, a center of the left planar coil SU1 and a center of the right planar coil SU2 thereof are electrically connected by a connecting conductor 83.

[0046] The connecting conductor 83 is formed of a conductor spanning a spiral pattern of each coil, and, for example, a wire harness with an arc shape can be used. The connecting conductor 83 may be referred to as a center connecting conductor.

[0047] Furthermore, an end portion of the right planar coil SU2 of the left planar coil SU1 on a side opposite the center and an end portion of the right planar coil SU1 thereof on a side opposite the center are electrically connected by a connecting conductor CN1 formed of a conductor pattern on the same layer as each planar coil. The connecting conductor CN1 may be referred to as an end portion connecting conductor.

[0048] The end portion connecting conductor CN1 is a conductor pattern, in other words, a wiring that connects a first end portion on the side opposite to the center of the planar coil SU1 to a second end portion on the side opposite to the center of the right planar coil SU2 thereof.

[0049] The end portion connecting conductor CN1 includes a lead-out wiring portion F1 linearly led out in the right direction from the first end portion, a wiring portion F2 extending in the +Y direction orthogonal to the lead-out wiring portion F1, in other words, in the positive width direction, and a wiring portion F3 extending in the right direction from the end portion of the wiring portion F2 and connected to the second end portion. Each of F1 to F3 is surrounded by a dashed ellipse.

[0050] The end portion connecting conductor CN1 is led out in the right direction from the first end portion of the planar coil SU2 through the wiring portion F1, extends in the +Y direction through the wiring portion F2, and the wiring portion F3 is led out in the right direction from the end portion of the wiring portion F2 and is electrically connected to the second end portion of the planar coil SU1.

[0051] In the Fig. 1, since the current flows from the terminal B to the terminal A, in the end portion connecting conductor CN1, the current flows from the wiring portion F3 to the left via the wiring portions F2 and F1 and reaches an end portion of the planar coil SU2.

[0052] In the planar coil SU2, the current also flows to the left. Thus, the wiring sections F2 and F1 can be said to realize current flow in the same rotational direction as the rotational direction of the current in the next planar coil SU2, which is a connection target. With this configuration, a path length of the end-section connecting conductor CN1, in other words, a length of the conductor pattern, can be suppressed to a minimum limit. Furthermore, the shape of the end-section connecting conductor CN1 is a shape that conforms to the shape of the spiral of the planar coil. Accordingly, electrical signal loss can be suppressed to a minimum limit.

[0053] Furthermore, in the planar coil array AR, planar coils are arranged at an interval d in the horizontal direction. The above interval d is realized by the wiring portions F1 and F3 of the end portion connecting conductor CN1. Thus, the planar coils are regularly arranged in a balanced manner with the interval d therebetween.

[0054] In this way, the end portion connecting conductor CN1 as the conductor pattern that electrically connects the end portions of the two adjacent planar coils completely matches the spiral patterns of the planar coils SU2 and SU1, and a large loss of the electrical signal does not occur in the end portion connecting conductor CN1.

[0055] A lower side of Fig. Figure 1 shows an equivalent circuit of the planar coil array. When designing the circuit of the planar coil array, it is necessary to design the planar coil array as a distributed constant circuit, which serves as a circuit model of a high-frequency signal transmission path, taking into account the relatively high frequency of an electrical signal flowing through the planar coil array.

[0056] Here is the equivalent circuit shown on the lower side of Fig. 1, a circuit including the inductances Na to Nd of the four coils and the connection paths DT1 to DT3 connecting the inductances. The connection paths DT1 to DT3 correspond to the center connection conductor 83 and the end-portion connection conductor CN1. Parasitic capacitances Ca to Cd are formed in the respective inductances and connection paths.

[0057] The equivalent circuit shown on the lower side of Fig. The circuit shown in Figure 1 is a distributed constant voltage circuit in which the inductances and capacitances are distributed in a balanced manner. Thus, large transmission losses do not occur in an AC electrical signal flowing between the power supply terminals A and B.

[0058] In other words, the planar coil array AR functions as a low-loss transmission path. For example, when the planar coil array AR is applied to a displacement sensor, the electrical signal can be detected at a high S / N ratio. In other words, a high-gain displacement sensor is realized.

[0059] Here we refer to a comparative example of Fig. 23 to illustrate features of the planar coil assembly AR in the embodiment of the present invention. Fig. 23 is a diagram showing a configuration example of a planar coil assembly as the comparative example. This comparative example was studied by the present inventors prior to the present invention and constitutes a part of the present invention.

[0060] As described above Fig. 1, Fig. 2 and Fig. 5 of Patent Literature Document 1, the planar coil arrangement is known in the prior art, and the planar coils used in the prior art are planar coils wound in opposite directions.

[0061] That is, as in A-1 of Fig. 23, by arranging a right-handed planar coil G1a, a left-handed planar coil G1b, a right-handed planar coil G2a, and a left-handed planar coil G2b with respect to the center along a predetermined direction, a coil that is long in the predetermined direction can be manufactured.

[0062] However, in the planar coil arrangement in the prior art, as can be seen from Fig. 1 of Patent Literature Document 1, the planar coil assemblies are connected in parallel to power supply terminals, and the planar coils are not electrically connected.

[0063] In this configuration, wirings B20, B20', B21, B21', B22, B22', B23 and B23' are necessary for parallel connection and terminals K1 to K6, and it is undeniable that the configuration for electrically connecting the planar coils is complicated and enlarged.

[0064] Furthermore, as described above, since each planar coil is not electrically connected, the planar coils cannot be used for applications where electrical signals need to be transmitted across each planar coil, such as a displacement sensor.

[0065] As a countermeasure, the present inventors considered a configuration in which planar coils are connected in series between terminals, as indicated by A-2. Conductors B24, B25, and B26 are used for electrical connection between the planar coils. The configuration indicated by A-2 is part of the present invention and does not belong to the prior art.

[0066] In this case, the transmission path of the electrical signal is formed as a whole. However, one end portion of the planar coil G1b is located on a left side with respect to a center of the planar coil G1b, and one end portion of the planar coil G2b is located on a right side with respect to a center of the planar coil G2b. In other words, the end portions are located on the opposite sides in the left-right direction, and the end portions are arranged with a large distance Lx therebetween. Thus, a large parasitic resistance Rk and large parasitic capacitances Ck1 and Ck2 are formed.

[0067] In other words, a wiring section connecting the end portions does not match the spiral shape of each planar coil, and a large loss of the high-frequency signal occurs in the wiring section. That is, a low-loss transmission path cannot be formed.

[0068] Here, with further reference to Fig. 1 the description continues. In the planar coil arrangement AR, which is located in the center of Fig. 1, the conductor pattern for electrically connecting the planar coils is simplified, and an overall size is reduced.

[0069] Furthermore, as described above, the end-portion connection wiring CN1 is particularly simplified. The end-portion connection wiring CN1 fully matches the spiral shape of the planar coil, and the transmission loss of the electrical signal can be suppressed to a minimum. In other words, a low-loss transmission path can be realized.

[0070] In this way, the winding direction of the spiral is the same, but by using the spiral shape whose phase is deviated by 180 degrees, an excellent effect of simplifying an electrical connection configuration and realizing the low-loss transmission path can be obtained.

[0071] In the following description, the planar coil SU1 means a first type of planar coil and is referred to as a first planar coil, and the planar coil SU2 means a second type of planar coil and is referred to as a second planar coil.

[0072] For example, focusing on the arrangement of the four planar coils located in the center of Fig. 1, the left planar coil SU1 may be referred to as the first planar coil, the right planar coil SU2 may be referred to as the second planar coil, the right planar coil SU1 thereof may be referred to as a third planar coil, and the right planar coil thereof may be referred to as a fourth planar coil.

[0073] Whether the expression focuses on a type of spiral shape or on the arrangement of the spiral is determined based on the context.

[0074] Next, Fig. 2 is referred to. Fig. Figure 2 is a diagram showing an arrangement of the two planar coils used in Fig. 1 are arranged adjacent to each other, showing a direction of a flowing current and an electrical connection. In Fig. 2 are the same components as those in Fig. 1 are designated by the same reference numerals.

[0075] A top of Fig. Figure 2 shows the spiral shapes in a plan view when the planar coils SU1 and SU2 are arranged side by side and each planar coil is viewed from the +Z direction. The center of each of the planar coils SU1 and SU2 is designated by a reference numeral 50.

[0076] A dashed rectangle is shown in each of the planar coils SU1 and SU2, and the dashed rectangle is shown to indicate a portion of one turn of a winding. The planar coils SU1 and SU2 both have three turns, and the number of turns is the same.

[0077] In the planar coil SU1, a first winding section P11 and a third winding section P13 are indicated by thick solid lines and a second winding section P12 is indicated by a thick dash-dotted line.

[0078] In the planar coil SU2, a first winding section P21 and a third winding section P23 are indicated by thick solid lines and a second winding section P22 is indicated by a thick dash-dotted line.

[0079] The planar coil SU1 has a configuration in which a conductor pattern, in other words, the winding P1, is wound three times in a left-handed manner around the center 50 of the planar coil SU1. The planar coil SU2 has a configuration in which a conductor pattern, in other words, the winding P2, is wound three times in a left-handed manner around the center 50 of the planar coil SU1. In this respect, it is common to the planar coil SU1. However, the spiral shape of the planar coil SU2 has a shape that deviates by 180 degrees from the spiral shape of the planar coil SU1.

[0080] In the planar coils SU1 and SU2, sections 60 are shown, which are surrounded by dashed circles. In the planar coil SU1, a lead-out wiring QL led out in the left direction is connected to the center 50, and the first winding section P11 moves half a circumference to reach the section 60. On the other hand, in the planar coil SU2, the lead-out extraction wiring QL led out in the right direction is connected to the center 50, and the lead-out position is the section 60. Thus, the phase of the spiral shape is deflected by half a circumference, that is, 180 degrees. In other words, the planar coils SU1 and SU2 have a relative positional relationship in which, when one planar coil is rotated left or right by 180 degrees, one planar coil overlaps the other planar coil.

[0081] As in the middle of Fig. 2, from the planar coil SU1, currents flow in the same direction from a -Y side to a +Y side in wirings L4 to L6 located on the side of the planar coil SU2 with respect to the center 50, that is, to the right of the center 50.

[0082] The same applies to the planar coil SU2, and currents in the same direction from the -Y side to the +Y side flow in wirings L7 to L9, which are located on the side of the planar coil SU1 with respect to the center 50, that is, to the right of the center 50.

[0083] The plurality of wirings L4 to L9 can be collectively referred to as wirings of an adjacent region in the adjacent planar coils SU1 and SU2. The current flowing in the same direction is generated in each wiring in the adjacent region of the planar coils SU1 and SU2, and accordingly, a magnetic field in the common direction is generated in each of the wirings L4 to L9 according to Ampere's rule of thumb. By combining the magnetic fields, the magnetic field is strengthened in the horizontal direction. Thus, as shown on a bottom of Fig. 2, a strong magnetic field BS2 is generated in the adjacent region of the planar coils SU1 and SU2.

[0084] In the following description, a clockwise magnetic field of the magnetic fields generated according to Ampere's rule of thumb is referred to as a rightward magnetic field or a clockwise magnetic field. A counterclockwise magnetic field is referred to as a leftward magnetic field or a counterclockwise magnetic field.

[0085] In the one on the underside of Fig. In the example shown in Figure 2, a magnetic field BS1 is generated to the left in a portion located to the left of the center 50 of the planar coil SU1, a magnetic field BS2 is generated to the right in the adjacent area of ​​the planar coils SU1 and SU2, and a magnetic field BS3 is generated to the left in the portion located to the right of the center 50 of the planar coil SU2. In this way, the magnetic fields are generated in opposite directions alternately in the horizontal direction, that is, along the predetermined direction.

[0086] In the example of the bottom of Fig. 2, a wire harness 83 with an arc shape is used as a center connecting conductor connecting the centers of the planar coils SU1 and SU2. A bonding wire can be used instead of the wire harness.

[0087] Next, Fig. 3 is referred to. Fig. 3 is a diagram showing another example of the arrangement of the two planar coils arranged adjacent to each other, the direction of the flowing current, and the electrical connection. A top view of Fig. Figure 3 shows the spiral shapes when the planar coils SU1 and SU2 are arranged side by side and each planar coil is viewed from the +Z direction. The center of each of the planar coils SU1 and SU2 is designated by reference numeral 50.

[0088] In Fig. 3, the planar coils SU1 and SU2 are both right-handed and the winding directions are different from those in the example of Fig. 2. The phase of the spiral of the planar coil SU2 is deflected by 180 degrees with respect to the phase of the spiral of the planar coil SU1.

[0089] Accordingly, the direction of the current flowing through each of the planar coils SU1 and SU2 is opposite to that in the example of Fig. 2 and the direction of the generated magnetic field is also opposite. Since the description of Fig. 2 also on Fig. 3 is applicable, a detailed description thereof is omitted.

[0090] The reference symbols P3 and P4 in Fig. 3 correspond to the reference symbols P1 and P2 in Fig. 2. The reference symbols P31 to P33 and P41 to P43 in Fig. 3 correspond to the reference symbols P11 to P13 and P21 to P23 in Fig. 2. The reference symbols L4' to L9' in Fig. 3 correspond to the reference symbols L4 to L9 in Fig. 2. The reference symbols BS4 to BS6 in Fig. 3 correspond to the reference symbols BS1 to BS3 in Fig. 2.

[0091] Next, Fig. 4 is referred to. Fig. Figure 4 is a diagram showing another example of the electrical connection between the two planar coils used in Fig. 2 are arranged adjacent to each other.

[0092] The diagram, which is on a top of Fig. 4 is the same as the diagram shown in the middle of Fig. 2, as described above. In the diagram shown on the bottom of Fig. However, as shown in Figure 4, a bridge electrode, an electrode having a multilayer structure, or a wiring having a multilayer structure is used as a central connecting conductor 87 connecting the center of the planar coil SU1 to the center of the planar coil SU2. In this respect, the configuration is different from that of the example of Fig. 2. The obtained effect is the same as in Fig. 2. <Ausführungsform 2>

[0093] In the present embodiment, a planar coil assembly having a multi-layer structure is described. Fig. 5 is referred to. Fig. 5 is a diagram showing an example of an arrangement of the planar coil assembly having the multilayer structure using four planar coils, current flows, and an electrical connection.

[0094] In the example of Fig. 5, the planar coil assembly is formed with the multilayer structure. The multilayer structure may be a multilayer structure according to a double-sided mounting technique for a printed circuit board or a multilayer structure according to a multilayer wiring technique for forming an interlayer insulating layer and a multilayer wiring layer on a board.

[0095] In Fig. 5, the left-handed planar coils SU1 and SU2, which were previously mounted on the top side of Fig. 2 were used as planar coils on a top layer.

[0096] Furthermore, the right-handed planar coils previously mounted on top of Fig. 3 are used as planar coils on a lower layer. In other words, the planar coils on the lower layer are formed to overlap the planar coils on the upper layer in a plan view, and the planar coils on the upper layer and the planar coils on the lower layer corresponding to the planar coils have opposite spiral winding directions of the planar coils. In other words, a relative positional relationship is obtained in which, when a spiral is reversed horizontally, one spiral overlaps the other spiral.

[0097] However, in Fig. 3 the right-handed planar coils are indicated with the reference symbols SU1 and SU2, but in Fig. 5, since it is necessary to distinguish them from the planar coils SU1 and SU2 on the upper layer, the planar coils on the lower layer are designated by the reference symbols SU3 and SU4.

[0098] A top of Fig. Figure 5 shows spiral shapes when the planar coils SU1 and SU2 are arranged side by side on the upper layer and each planar coil is viewed from the +Z direction. Furthermore, a bottom side of Fig. 5 spiral shapes when the planar coils SU3 and SU4 are arranged side by side on the lower layer and each planar coil is viewed from the +Z direction. The center of each of the planar coils SU1 to SU4 is designated by reference numeral 50.

[0099] The directions of the currents flowing in the planar coils SU1 to SU4 are indicated by white arrows. When the planar coils SU1 and SU3 overlap, current flows in the same direction in the vertically overlapping wirings. Similarly, when the planar coils SU3 and SU4 overlap, current flows in the same direction in the vertically overlapping wirings.

[0100] Each of the four planar coils SU1 to SU4 has a different spiral shape. That is, in the example of Fig. 4, the electrical path can be formed by combining four kinds of spiral shapes, and a degree of freedom in designing the device is improved.

[0101] For simplicity, the planar coils SU1 to SU4 can be referred to as the first to fourth planar coils.

[0102] The planar coils SU1 and SU3 are stacked to overlap each other in plan view, the planar coil SU1 is left-handed, the planar coil SU2 is right-handed, and centers of the planar coils SU1 and SU3 are electrically connected to each other by a center connection conductor DE1 extending in the Z direction, that is, along the top-bottom direction.

[0103] The planar coils SU2 and SU4 are stacked to overlap each other in plan view, the planar coil SU2 is left-handed, the planar coil SU4 is right-handed, and the centers of the planar coils SU2 and SU4 are electrically connected to each other by a center connection conductor DE2 extending in the Z direction, that is, along the top-bottom direction.

[0104] Furthermore, the planar coil SU3 and the planar coil SU4 are formed from a conductor on the same layer, and respective end portions are electrically connected by an end portion connecting conductor CN2. The end portion connecting conductor CN2 is formed from a conductor on the same layer as the planar coils SU3 and SU4, has a similar shape and function to the above-described end portion connecting conductor CN1, and produces similar effects.

[0105] In Fig. 5, the end section connecting conductor CN2 has wiring sections F1', F2' and F3'. The sections correspond respectively to the wiring sections F1, F2 and F3 of the Fig. 1. The end-section connecting conductor CN2 matches the spiral of the planar coils SU3 and SU4, and electrical signal loss is suppressed, ensuring a low-loss transmission path.

[0106] Further, the middle connecting conductors DE1 and DE2 may be implemented, for example, by an electrode called a contact plug formed by embedding a conductor in a through hole formed in a printed circuit board, or a contact electrode formed by a contact hole formed in an interlayer insulating film.

[0107] When the planar coils SU1 and SU3 are stacked, since current flows in the same direction in each of the vertically overlapping wirings, magnetic fields are generated in the same direction, which mutually reinforce each other in the up-down direction. Similarly, when the planar coils SU3 and SU4 are stacked, since current flows in the same direction in each of the vertically overlapping wirings, magnetic fields are generated in the same direction, which mutually reinforce each other in the up-down direction.

[0108] Further, even in the wiring portion F2' of the end portion connecting conductor CN2, a current flows in the same direction in each of the vertically overlapped wirings, and magnetic fields in the same direction are generated.

[0109] A strong magnetic field BS8 is generated by combining the magnetic fields in the same direction generated in this way and amplifying the magnetic fields in the horizontal direction and the up-down direction.

[0110] In the example of Fig. 5, a magnetic field BS7 is generated to the left in sections of the planar coils SU1 and SU2 located to the left of the center 50.

[0111] Further, the magnetic field BS8 is generated to the right in the adjacent region of the planar coils SU1 and SU2, an adjacent region of the planar coils SU3 and SU4, and the wiring portion F2' of the end portion connecting conductor CN2 arranged between the planar coils SU3 and SU4.

[0112] Furthermore, a magnetic field BS9 is generated to the left in portions of the planar coils SU2 and SU4 located to the right of the center 50. In this way, the magnetic fields are generated in opposite directions alternately in the horizontal direction, that is, along the predetermined direction.

[0113] Next, Fig. 6A is referred to. Fig. Figure 6A is a diagram showing a configuration in which a movable conductor is arranged near a planar coil assembly having a multilayer structure using eight planar coils. Fig. 6A, the same parts as those in the preceding drawings are designated by the same reference numerals.

[0114] In the example of Fig. 6A shows another multi-layer structure including the four planar coils arranged in Fig. 5, the multilayer structures are arranged adjacently in the horizontal direction, and the multilayer structures are electrically connected in the horizontal direction using the end portion connecting conductor CN1.

[0115] The centers of the planar coils, which are stacked vertically, are connected by the center connecting conductors DE1 and DE2, as described above. However, in Fig. 6A, in order to distinguish the four center connecting conductors used from each other, the center connecting conductors are designated from left to right by the reference symbols DE1 to DE4.

[0116] Accordingly, a planar coil array AR is formed, which has a multilayer structure including eight planar coils and also serves as a transmission path for an electrical signal. The current flow direction is indicated by a white arrow.

[0117] A plate-shaped conductor M10, which is movable and horizontally long, is arranged near the planar coil assembly AR. This configuration is essentially the same as the configuration in which the movable cylindrical conductor M1, previously arranged on the top of Fig. 1 is adapted to the horizontally long coil CL1.

[0118] In the example of Fig. 6, when the plate-shaped conductor M10, which is horizontally long, moves in the horizontal direction, the inductance of each planar coil in the planar coil array AR and electrical properties of the electrical signal transmitted through the planar coil array AR, for example, a frequency, change. By detecting the change in frequency, the amount of movement of the conductor M10 can be detected. Thus, the planar coil array AR can be Fig. 6 may be a component of the displacement sensor.

[0119] Next, Fig. 6B is referred to. Fig. Figure 6B is a cross-sectional view of the planar coil assembly and the movable conductor in Fig. 6A.

[0120] In the example of Fig. 6B, the multilayer structure using the double-sided mounting technique is formed for a printed circuit board 311, and the following description will be made. When the multilayer wiring technique using the interlayer insulating layer is used, reference numeral 311 indicates an interlayer insulating layer formed on a semiconductor board or an insulating board.

[0121] When the printed circuit board 311 is a rigid board without flexibility on a flat plate, for example, a glass epoxy resin or a polyimide resin can be used as a material thereof. When the printed circuit board 311 is a flexible board with flexibility, for example, a polyimide resin film or a polyester resin film can be used as the material thereof. However, this is merely an example, and the present invention is not limited to these examples.

[0122] The planar coil SU1 on the upper layer, located at a left end, is formed from a metal conductor 310 formed on a front surface of the circuit board 311. For example, silver or copper can be used as the metal. A thin film of silver or copper is formed on the circuit board 311 and patterned by photolithography to form a spiral-shaped pattern.

[0123] The planar coil SU2, which is arranged to overlap the planar coil SU1 in a top plan view, is formed by the conductor 312. The central connecting conductor DE1, which connects the centers of the planar coils SU1 and SU2, may be composed of, for example, a metal electrode made of, for example, copper, buried and formed in a through-hole VIAH formed to penetrate the circuit board 311.

[0124] The conductors 314, 318 and 324 formed on the front surface of the circuit board 311, the end portion connecting conductor CN1 and the conductors 316, 320 and 326 and the end portion connecting conductor CN2 formed on a rear surface of the circuit board 311 are also made of the above metal material and are patterned into a predetermined pattern by photolithography.

[0125] When the multilayer structure using the double-sided mounting technique or the like is used for the printed circuit board, the thin and small-sized planar coil array AR can be manufactured at low cost, easily and stably using the existing semiconductor processing technology.

[0126] Furthermore, since the planar coil assembly AR has a flat plate shape, it is possible to arrange the flat plate-shaped movable conductor M10 closely without difficulty. Accordingly, for example, a small-sized displacement sensor can be formed.

[0127] In the example of Fig. 6B, the magnetic field BS7 to the left, the magnetic field BS6 to the right, the magnetic field BS9 to the left, the magnetic field BS10 to the right, and the magnetic field BS11 to the left are generated from left to right. That is, the magnetic fields with opposite directions are generated alternately in the horizontal direction. The strength of each magnetic field is uniform, and a stable magnetic field can be generated in a balanced manner.

[0128] The above description is summarized as follows.

[0129] That is, the planar coil assembly includes: the first planar coil SU1 having a first spiral shape in which the first conductor 310 is wound left-handed or right-handed around the first center 50; and the second planar coil SU2 having a second spiral shape in which the second conductor 314 is wound on the same layer as the first conductor in the same manner as the first planar coil SU1 around the second center 50 and has an angular deviation from the first spiral shape.

[0130] In a preferred example, the angular deviation may be 180 degrees.

[0131] Accordingly, the conductor pattern for electrically connecting the planar coils is simplified, and the overall size is reduced. In particular, the end-portion connection wiring for connecting the end portions of the two planar coils can be simplified. Furthermore, the end-portion connection wiring fully conforms to the spiral shape of the planar coil, and the transmission loss of the electrical signal can be suppressed to a minimum. Accordingly, the excellent effect of simplifying the electrical connection configuration and realizing a low-loss transmission path can be obtained.

[0132] Further, the planar coil assembly AR may include: the third planar coil SU3 formed of the third conductor 312 on a different layer from the first conductor 310 and arranged to overlap the first planar coil SU1 in a plan view; and the fourth planar coil SU4 formed of the fourth conductor 316 on the same layer as the third conductor 312 and arranged to overlap the second planar coil SU2 in the plan view.

[0133] Accordingly, by using a multilayer structure, it is possible to generate a strong magnetic field by combining magnetic fields in the same direction that are mutually enhanced in the up-down direction. Furthermore, a magnetic field in the same direction is also generated in an adjacent region of an adjacent planar coil in the same layer, and a magnetic field in the same direction is also generated in an end-portion connecting conductor. Thus, by combining these magnetic fields, it is possible to efficiently generate the strong magnetic field enhanced in the horizontal direction and the up-down direction.

[0134] Furthermore, in the planar coil assembly AR, the third planar coil SU3 may have a spiral shape in which the third conductor 312 is wound around the third center 50 in a direction opposite to the first planar coil SU1, and the fourth planar coil SU4 may have a spiral shape in which the fourth conductor 316 is wound around the fourth center 50 in a direction opposite to the second planar coil SU2.

[0135] Accordingly, since the current flows in the same direction in each of the vertically overlapping wires, magnetic fields are generated in the same direction, reinforcing each other in the up-down direction. By combining these magnetic fields, a strong magnetic field can be efficiently generated.

[0136] Further, the third and fourth planar coils SU3 and SU4 may be formed in a multilayer structure according to a double-sided mounting technique for a printed circuit board or a multilayer structure according to a multilayer wiring technique for forming an interlayer insulating layer and a multilayer wiring layer on a board.

[0137] Accordingly, the multilayer structure can be formed easily, inexpensively, and with high reliability using semiconductor processing technology. <Ausführungsform 3>

[0138] In the present embodiment, a magnetic shielding structure of a planar coil assembly is described. Fig. 7 is referred to. Fig. 7 is a cross-sectional view of a structure in which shielding members for shielding a magnetic field are provided between the planar coil assembly and an object to be protected arranged around the planar coil assembly.

[0139] The planar coil arrangement AR in Fig. 7 is the same as the planar coil arrangement in Fig. 6B. Since the configuration of the planar coil array AR has been described above, its description is omitted here.

[0140] Objects to be protected 502 and 504 are provided around the planar coil arrangement AR. The object to be protected may be referred to as a peripheral conductor.

[0141] The object to be protected is an element or device that requires protection from the magnetic field generated by the planar coil array AR. Examples of the object to be protected include a conductive element arranged around the planar coil array and requiring protection from the magnetic field, a semiconductor device or an integrated circuit device that requires protection from the magnetic field, or an electronic device.

[0142] A magnetic shielding element 402 is provided between the planar coil arrangement AR and the object to be protected 502 arranged around the planar coil arrangement AR, and a magnetic shielding element 404 is provided between the planar coil arrangement AR and the object to be protected 504.

[0143] The magnetic shielding element can be simply referred to as a shielding element. The magnetic shielding element can be an electromagnetic shielding element that shields both an electric field and the magnetic field.

[0144] For example, a metal such as iron or a magnetic material can be used as the material of the magnetic shielding member. The magnetic shielding member may be provided with a slit that meets a predetermined condition. This will be described later.

[0145] For example, an electrical insulating material containing magnetic powder, in other words, a magnetic resin compound, can be used as the magnetic shielding member. This will be described later.

[0146] It is preferable that the magnetic shielding members 402 and 404 are arranged along the X direction, which is an extending direction of the planar coil array AR, and cover the planar coil array AR so as to overlap the planar coil array AR in a plan view viewed from the +Z direction or the -Z direction.

[0147] Next, Fig. 8 is referred to. Fig. 8 is a diagram showing a configuration in which the magnetic shielding member functions as a yoke as a component of the magnetic circuit.

[0148] A-1 of Fig. Figure 8 is a plan view of a configuration in which the planar coils SU1 and SU2 are arranged side by side. This configuration is the same as that previously described with reference to Fig. The configuration described in Figure 2. The direction of the current is indicated by a white arrow.

[0149] An area between the centers 50 of the planar coils SU1 and SU2 is an adjacent area. In the adjacent area, there are six conductor patterns, L4 to L9, extending in the Y direction, in other words, wirings. Since current flows through each wiring from the -Y side to the +Y side, in this adjacent area, the magnetic fields generated by the wirings combine to generate the strong magnetic field BS2 to the right.

[0150] In A-2 of Fig. 8, two pairs of planar coils are used, in which one pair is composed of planar coils SU1 and SU2, and by arranging the two pairs of planar coils in the X direction, the planar coil array AR is formed, which extends in the X direction. Since the planar coil array AR has the same configuration as the planar coil array described with reference to Fig. 1, it is in Fig. 8 is shown in a simplified manner.

[0151] In the planar coil arrangement AR of A-2 of Fig. 8, a current 35 flows from a right side to a left side at a certain time. As a result, the magnetic field BS2 is generated. A portion of a magnetic flux constituting the magnetic field BS2 leaks into the atmosphere, and a leakage flux 29, surrounded by a dashed ellipse, is present in this figure.

[0152] Here, as in A-3 of Fig. As shown in Figure 8, when a configuration in which the magnetic shielding member 402 is disposed close to the planar coil assembly AR is used, the magnetic shielding member has a significantly higher magnetic permeability than the atmosphere, and the magnetic flux is more likely to pass therethrough. Thus, the above leakage flux flows through the magnetic shielding member 402, so that the leakage flux can be effectively utilized. Accordingly, the magnetic flux density is improved. In Figure A-3 of Fig. 8, a magnetic flux BX flowing from left to right is generated in the magnetic shielding element 402.

[0153] In other words, the magnetic flux generated by the wirings L4 to L6 of the first planar coil SU1 and the magnetic flux generated by the wirings L7 to L9 of the adjacent second planar coil SU2 can be efficiently coupled. This increases the magnetic flux density and enhances the magnetic field BS2.

[0154] A portion of the magnetic shielding member 402 where the magnetic flux BX flows acts as the yoke that couples the magnetic fluxes of two adjacent planar coils in the planar coil array AR to increase the magnetic flux density.

[0155] The magnetic shielding element with the function of a yoke is a multifunctional element with two functions, which can be referred to as a magnetic shielding element that serves as a yoke or a shielding element that serves as a yoke. The shielding element that serves as a yoke can be referred to as a yoke shielding element.

[0156] In this way, by arranging the magnetic shielding member close to the planar coil assembly, the magnetic shielding member can function as the yoke, thereby improving the magnetic flux density and generating a stronger magnetic field.

[0157] Furthermore, when the magnetic shielding member is arranged close to the planar coil assembly, a size reduction effect that the structure formed by the magnetic shielding member and the planar coil assembly is reduced in size and can be installed in a narrow space is also obtained.

[0158] However, according to the study of the present inventors, it has become clear that when the magnetic shielding member is arranged near the planar coil assembly, an undesirable effect may also be generated due to the planar coil assembly acting as a transmission path of an AC signal.

[0159] That is, when a conductive magnetic shielding member is disposed near a planar coil array extending along a predetermined direction and also serving as a path of an electric signal, that is, near the planar coil array, a structure similar to a microstrip line, which is a transmission path of a high-frequency signal, is formed in a pseudo manner. When the frequency of the electric signal is high, a current called a reverse current flows through the conductive magnetic shielding member. A magnetic field generated by the reverse current acts to cancel the magnetic field of the planar coil array, and a new problem arises that a strength of the magnetic field generated by the planar coil array decreases. This problem will be described below.

[0160] It will be Fig. 9 is referred to. Fig. Figure 9 is a diagram showing an example of an undesirable effect due to the planar coil assembly acting as the transmission path of the AC signal.

[0161] A-1 of Fig. Figure 9 shows a typical structure of the microstrip line. A microstrip line 34 has a flattened structure in which divided pieces obtained by splitting a coaxial cable into two in a cross-sectional shape are flattened.

[0162] In A-1 of Fig. 9, a signal transmission path 36 corresponds to the inner conductor of the coaxial cable, and a high-frequency signal 38 is transmitted through the signal transmission path 36. A flat plate-shaped grounding conductor 33 is provided below the signal transmission path 36. The grounding conductor 33 corresponds to an outer conductor of the coaxial cable and has a function of shielding the magnetic field generated by the inner conductor.

[0163] The signal transmission path 36 and the grounding conductor 33 are arranged facing each other via a circuit board 31 made of a dielectric, which is an electrical insulator.

[0164] When a high-frequency current flows through the signal transmission path 36, a magnetic field EJ is generated from the signal transmission path 36 to the grounding conductor 33. When the magnetic field EJ crosses the grounding conductor 33, many eddy currents are generated on a front surface of the grounding conductor 33 due to a skin effect. Due to the electric field generated by the eddy current, a current 39 flows to cancel the magnetic field EJ. Since a direction of the current 39 is opposite to a direction of the high-frequency signal 38 flowing through the signal transmission path 36, the current 39 is generally referred to as the reverse current.

[0165] When the return current is generated, the magnetic field generated by the return current 39 cancels the magnetic field EJ generated by the high-frequency signal 38, thereby weakening the strength of the magnetic field EJ.

[0166] Here, when the structure of the microstrip line is compared with a structure formed by the planar coil array AR and the magnetic shielding member 404 shown in A-2 of Fig. 9, it is understood that both have similar structures.

[0167] That is, the planar coil arrangement AR corresponds to the signal transmission path 36 and the magnetic shielding element 404 corresponds to the grounding conductor 33.

[0168] Furthermore, the printed circuit board or the interlayer insulating layer 311 previously described in Fig. 7, the dielectric board 31 in the microstrip line 34.

[0169] The magnetic shielding element 402 is arranged above the planar coil arrangement AR and close to the planar coil arrangement AR. The magnetic shielding element 402 also has the same function as the magnetic shielding element 404 arranged below the planar coil arrangement AR as an electrical configuration. Thus, the magnetic shielding element 402 can also be considered to correspond to the grounding conductor 33 in the microstrip line 34.

[0170] In A-2 of Fig. 9, a return current 47 is generated in the magnetic shielding member 404 disposed under the planar coil array AR. That is, the magnetic field BS2 is generated by the current signal flowing from right to left from the planar coil array AR, in other words, the high-frequency current signal 35. When the magnetic field BS2 crosses the magnetic shielding member 404, many eddy currents are generated on a front surface of the magnetic shielding member 404 due to the skin effect, and the return current 47 flows due to the electric field generated by the eddy currents.

[0171] Then the magnetic field BJ is generated by the return current 47. As shown in A-3 of Fig. As shown in Figure 9, the magnetic field BS2 is a rightward magnetic field, while the magnetic field BJ is a leftward magnetic field in an opposite direction. Accordingly, the magnetic field BSJ acts to cancel the magnetic field BS2 generated by the planar coil array AR. Accordingly, the strength of the magnetic field BS2 is weakened, and the planar coil array AR cannot generate an original strong magnetic field.

[0172] A return current 47' is also generated in the magnetic shielding element 402, which is arranged above the planar coil assembly AR, by the same principle. A magnetic field BJ' generated by the return current 47' is in an opposite direction to the magnetic field BS2 generated by the planar coil assembly AR. Therefore, the magnetic field BJ' also acts to cancel the magnetic field BS2. Accordingly, the strength of the magnetic field BS2 is further weakened.

[0173] As described above, assume that the planar coil array is applied to a displacement sensor, for example. To improve the detection sensitivity of the displacement sensor, it is necessary to generate a strong magnetic field. If the magnetic field is weak, the detection sensitivity of the displacement sensor decreases. Accordingly, it is necessary to overcome the problem that the magnetic field generated by the planar coil array is weakened.

[0174] Next, a countermeasure for this problem is described. Fig. 10 is referred to. Fig. 10 is a diagram showing an example of a configuration of shielding elements for suppressing Fig. 9 shows undesirable effects.

[0175] The present inventors have found that by suppressing the current flowing through the magnetic shielding elements, the Fig. 9 can alleviate the problem described.

[0176] In the example of Fig. 10, a slit is provided in a conductive material plate constituting the magnetic shielding member to increase a resistance value of the magnetic shielding member in the direction in which the reverse current flows, thereby reducing a current amount of the reverse current.

[0177] Here, the slot is a cavity formed by cutting out a portion of the material plate. In a preferred example, the slot has an elongated rectangular shape extending in one direction.

[0178] In the following description, the term "magnetic shielding structure" may be used. The magnetic shielding structure preferably encompasses both the configuration of the magnetic shielding element itself and an arrangement of the magnetic shielding element with respect to the planar coil assembly, that is, a layout configuration that includes a relative positional relationship.

[0179] In A-1 of Fig. 10, a conductive magnetic shielding element 403 having slots 501 and 503 is disposed above and near the planar coil arrangement AR. The magnetic shielding element 403 functions as a path of an electrical signal 37' or as a transmission path.

[0180] Furthermore, a conductive magnetic shielding element 405 having slots 501 and 503 is disposed below and near the planar coil assembly AR. The magnetic shielding element 405 functions as a path for an electrical signal 37 or as a transmission path.

[0181] The magnetic shielding members 403 and 405 are conductive plate-shaped members extending in the X direction similarly to the planar coil array AR, and are arranged to cover the planar coil array AR and overlap the planar coil array when viewed from the +Y direction or the -Y direction in a plan view.

[0182] The magnetic shielding members 403 and 405 are magnetic shielding members that also serve as yokes having the function as the yoke previously described with reference to Fig. 8 was described.

[0183] The slit 501 is a horizontally long rectangular slit extending along the X direction, which is an extending direction of the magnetic shielding members 403 and 405 or along a broad direction, and has a predetermined length. In A-1 of Fig. 10, the magnetic shielding elements 403 and 405 are each provided with two slots 501 and 501.

[0184] By providing the slots 501, a cross-sectional area of ​​the path of the electrical signal in the magnetic shielding members 403 and 405 through the slots 501 is reduced, and the electrical resistance increases.

[0185] As in A-1 of Fig. As shown in Figure 10, the electrical resistance is distributed along the X-direction and inserted into the path of the electrical signal. This electrical resistance acts as a current-limiting resistor, limiting the reverse current described above. Accordingly, the reverse current is suppressed. As a result, the problem of the magnetic field generated by the planar coil arrangement AR being canceled and weakened is alleviated.

[0186] The slit 501 is a slit extending in the X direction and can be referred to as a slit for suppressing the reverse current.

[0187] Slot 503 is a slot that intersects the X direction, in other words, a direction at a right angle, i.e., orthogonal to the X direction. Slot 503 also has the same effect as slot 501.

[0188] There are two slots 503, one of which is a slot cut into a center of the plate-shaped planar coil assembly AR from an end portion on a +Y direction side in the Y direction. The other is a slot cut into the center of an end portion on a -Y direction side.

[0189] The two slits are arranged to face each other at the same position in the X direction at an interval in the Y direction, and form the pair of slits 503 and 503.

[0190] However, only one of the two slots may be provided. That is, at least one of the pair of slots 503 and 503 is provided.

[0191] The slots 503 are provided at an intermediate position between the two slots 501 and 501 in the X direction.

[0192] Slot 503 has the same effect as slot 501. That is, by providing slots 503, the cross-sectional area of ​​the electrical signal path in the magnetic shielding elements 403 and 405 is reduced, and the electrical resistance increases. The electrical resistance acts as a current-limiting resistor that limits the reverse current described above. Accordingly, the reverse current is suppressed. As a result, the problem that the magnetic field generated by the planar coil array AR is canceled and weakened is alleviated.

[0193] The slit 503 is a slit extending in the Y direction orthogonal to the X direction, and similarly to the slit 501, it can be said to be a slit having a function of suppressing the reverse current.

[0194] It is preferable that the slots 501 and 503 are both provided, but the present invention is not limited thereto, and it may be assumed that either of the slots 501 and 503 is provided.

[0195] When the slot 501 and the slot 503 are connected to each other, a mechanical strength of the magnetic shielding members 403 and 405 is weakened, and thus the slots 501 and 503 are not connected to each other.

[0196] In this way, the magnetic shielding members 403 and 405 each have a conductor pattern in which at least one of the slots 501 and 503 is provided.

[0197] In other words, the conductor patterns of the magnetic shielding members 403 and 405 are conductor patterns provided with at least one of the slots 501 extending in one direction and the slots 503 extending in the direction orthogonal to the one direction, each having a function of suppressing the reverse current.

[0198] A-2 of Fig. 10 shows an example of a more detailed configuration of the magnetic shielding member 405. The slots 503 and 503 extending in the Y direction form a pair of slots G1.

[0199] Further, the plurality of slots 501 extending in the X direction are provided to form a slot group G2. The plurality of slots 501 are arranged parallel to each other at predetermined intervals in the Y direction. By providing the slot group G2, the reverse current can be suppressed more effectively.

[0200] Next, Fig. 11 is referred to. Fig. 11 is a view showing a relative positional relationship between the shielding members and the Fig. 10 shows the planar coil arrangement.

[0201] A-1 of Fig. 11 is a top view of the planar coil assembly using the four previously described Fig. 1. Since an electrical connection relationship between the planar coils as in Fig. 1, it is shown in A-1 by Fig. 11 omitted.

[0202] The above with reference to A-2 of Fig. 10 described magnetic shielding element 405 is shown in A-2 of Fig. 11. As shown in A-2 of Fig. As shown in Figure 11, the slot group G2, which has a plurality of slots, is provided to correspond to an adjacent region of the two adjacent planar coils SU2 and SU1 in the planar coil assembly. Here, the adjacent region is a region between the center 50 of the planar coil SU2 and the center 50 of the planar coil SU1. In Figure A-1 of Fig. 11, a region indicated by a reference symbol WS corresponds to the adjacent region. The adjacent region may be referred to as an adjacent part or an adjacent section.

[0203] The term “adjacent region” may refer to a region of the planar coil assembly or may refer to a region corresponding to the region in the magnetic shielding element.

[0204] As described above, a strong magnetic field is generated in the adjacent region of the two adjacent planar coils SU2 and SU1 by combining a plurality of magnetic fields in the same direction. A large reverse current may be generated due to the strong magnetic field. Thus, the slot group G2, which has a plurality of slots, is arranged correspondingly to the adjacent region. In other words, the slot group G2 is arranged to vertically overlap the adjacent region. Accordingly, the reverse current can be effectively suppressed.

[0205] The pair of slots G1 is provided to correspond to the position of each center 50 of the planar coils SU2 and SU1 in the X direction.

[0206] Since the planar coil array AR extends long in one direction, the adjacent region of two adjacent planar coils is often continuous along one direction. In this case, slots 503 are provided in each adjacent region of the magnetic shielding member 405 in a direction orthogonal to one direction, and the reverse current generated in one adjacent region is prevented from flowing to the next adjacent region with the remaining current. Accordingly, the reverse current can be effectively suppressed.

[0207] In this way, the reverse current generated in an adjacent region is prevented from flowing through the pair of slots G1 to the next adjacent region. Furthermore, in an adjacent region, the amount of reverse current generated in the adjacent region is reduced by the slot group G2. Accordingly, the reverse current can be effectively suppressed, and the problem of the magnetic field cancellation of the planar coil can be solved.

[0208] The one in A-2 of Fig. The magnetic shielding member 405 shown in Figure 11 is a novel multifunctional magnetic shielding member having a function as a magnetic shield, a function as a yoke, and a current limiting function for limiting a current flowing in one direction. Each function is achieved by disposing the magnetic shielding member 405 near the planar coil assembly AR in an appropriate relative positional relationship.

[0209] In other words, the new magnetic shielding structure is implemented by the configuration with respect to the shape of the conductor pattern provided with the slots in the magnetic shielding member 405 and the layout configuration with respect to the planar coil array AR.

[0210] The Fig. The structure shown in Figure 7 is shown again in A-3 of Fig. 11. However, the magnetic shielding elements are designated by the reference numerals 402 and 404 in Fig. 7 and are designated by the reference numerals 403 and 405 in A-3 of Fig. 11. Since the structure is described above, the description of the structure is omitted here.

[0211] Next, Fig. 12 is referred to. Fig. 12 is a diagram showing another configuration example of the magnetic shielding elements. A-1 of Fig. 12 is the same as A-1 of Fig. 11.

[0212] In A-2 of Fig. 12, in addition to the slots 501 and 503 described above, slot groups G3 are provided in a magnetic shielding member 407.

[0213] If A-2 of Fig. 12 with A-2 from Fig. 11 as described above, three on the +Y side and three on the -Y side of the nine first slots 501 formed in the slot group G2 in A-2 of Fig. 11 are replaced by the slot group G2. Three slots 501 are arranged in a central region between the slot groups G3 and G3.

[0214] The slot group G3 includes a slot including the bent portion. The slot including the bent portion includes a first slot portion 504 extending in the X direction and a pair of second slot portions 505 and 505 connected to both end portions, in other words, a left end portion and a right end portion, of the first slot portion 504 and extending in the Y direction orthogonal to the X direction.

[0215] When the above-described slot 501 is a first slot, the slot 502 is a second slot, and the slot including the bent portion is a third slot, the magnetic shielding member 407 of A-2 can be Fig. 12 can be referred to as a magnetic shielding element which has three types of slots with different patterns.

[0216] An advantage of using the third slot having the bent portion, in other words, the third slot having the bent pattern, is that the forward movement of the reverse current flowing along the X direction is blocked by the second slot portions 505 and 505 extending in the Y direction, and thus the resistance value of the electrical resistor in the X direction increases and the current limiting function is enhanced.

[0217] If attention is focused only on enhancing the current limiting function, the same effect can be obtained even if a large slot with a large width in the X direction is provided. However, in this case, since there is no conductive material in the large slot portion, no magnetic shielding effect or yoke effect occurs. Therefore, both the magnetic shielding effect of the magnetic shielding elements and the effect of the yoke amplifying the magnetic field are reduced.

[0218] On the other hand, when the third slot including the bent portion is used, a pattern 506 of a conductive material is present in the slot group G3, and the magnetic shielding effect or the effect as the yoke is obtained in the pattern 506 of the conductive material. Accordingly, it is possible to enhance the current limiting function while maintaining the magnetic shielding effect and the effect of enhancing the magnetic field by the yoke to a certain extent.

[0219] A-3 of Fig. 12 shows another example of the slit pattern. In a magnetic shielding element 409 shown in A-3 of Fig. 12, the slit 505 which is long in the horizontal direction and extends from the vicinity of one end portion in the X direction, that is, the vicinity of a left end portion to the vicinity of the other end portion, that is, the vicinity of a right end portion, is provided.

[0220] The configuration of A-3 from Fig. 12 can be considered as a configuration in which the slots 503 in the configuration of A-2 described above are Fig. 11 are removed and the slots 501 distributed along the X direction are connected to form one slot.

[0221] In other words, the value in A-3 of Fig. 12 can be considered as a configuration in which the above-described slot 501 extends long in the horizontal direction from the vicinity of one end portion of the magnetic shielding member to the vicinity of the other end portion of the magnetic shielding member. From this point of view, the slot 505 can be considered as a modification of the first slot 501 obtained by changing the length of the first slot 501.

[0222] In the example of A-3 of Fig. 12, since the plurality of slots 505 long in the horizontal direction are provided, a cross-sectional area of ​​an electrical signal path in the magnetic shielding member 409 can be effectively reduced. Accordingly, the current limiting function can be efficiently enhanced by only a simple linear slot.

[0223] As described above, according to the present embodiment, it is possible to provide the magnetic shielding structure of the planar coil array in which the magnetic field generated by the planar coil array can be shielded, and the strength of the magnetic field generated by each coil constituting the planar coil array can be suppressed with the simple configuration. <Ausführungsform 4>

[0224] It will be Fig. 13 is referred to. Fig. 13 is a diagram showing yet another configuration example of the magnetic shielding members. In the present embodiment, an example of using a magnetic resin compound obtained by mixing or kneading a magnetic material powder with an electrically insulating resin material as the magnetic shielding member will be described.

[0225] As in A-1 of Fig. As shown in Figure 13, the movable conductor M10 is disposed adjacent to the planar coil assembly AR. Flat plate-shaped magnetic shielding members 411 and 413 using the magnetic resin compound are provided above and below the movable conductor M10, respectively. Both magnetic shielding members 411 and 413 are preferably provided, and any of the magnetic shielding members 411 and 413 may be provided.

[0226] A-2 of Fig. 13 is the same as A-1 of Fig. 12. A-3 of Fig. 13 shows a shape of the magnetic shielding member 413 in a plan view. As in Fig. 13, the magnetic shielding member 413 has a rectangular shape in plan view extending along the X direction, which is the same as an extending direction of the planar coil array AR.

[0227] As described above, the magnetic shielding members 411 and 413 are formed by mixing or kneading the powder of magnetic material with the electrical insulating material.

[0228] For example, an epoxy resin or a polyimide resin can be used as the electrical insulating material. A ferromagnetic powder, for example, can be used as the magnetic material powder.

[0229] A ferromagnetic material is a substance that is more strongly magnetized in a magnetic field and remains magnetized even when the magnetic field is removed. Examples include iron, cobalt, nickel, alloys thereof, and ferrite. Ferrite is a magnetic oxide containing iron oxide as a main component. In addition to high magnetic permeability and high electrical resistance, it is also characterized by not generating eddy currents. Considering this point, ferrite can be considered one of the ferromagnetic materials used in the present embodiment. However, the materials described above are examples, and the present invention is not limited thereto.

[0230] The magnetic resin compound can be produced, for example, by molding a resin obtained by mixing or kneading a magnetic powder into a desired shape, by injection molding, and then firing the resin at a high temperature.

[0231] Since the magnetic shielding elements 411 and 413 are formed by mixing or kneading the ferromagnetic powder with the resin, the ferromagnetic powder is magnetized under the influence of the magnetic field BS generated by the planar coil array AR. Accordingly, the resin as the base material suppresses the leakage of magnetic flux to the outside. By appropriately adjusting the concentration of the ferromagnetic powder, the necessary magnetic shielding effect can be obtained.

[0232] Furthermore, when the ferromagnetic powder is magnetized by the influence of the magnetic field BS generated by the planar coil array AR, the ferromagnetic powder has a function of increasing the magnetic flux density, thereby performing a yoke function. That is, as described above, the magnetic shielding members 411 and 413 function as yokes that couple the magnetic fluxes of the two adjacent planar coils in the planar coil array AR.

[0233] On the other hand, since the base material of the magnetic shielding members 411 and 413 is an insulating resin, the eddy current does not flow on the front surfaces of the magnetic shielding members 411 and 413 due to the influence of the magnetic field BS generated by the planar coil array AR. Accordingly, the above-described reverse current does not occur, and the problem of canceling the magnetic field of the planar coil array AR is eliminated.

[0234] Accordingly, the magnetic shielding members 411 and 413 serve as multifunctional magnetic shielding members having the magnetic shielding effect, an effect of improving the magnetic flux density as the yoke, and an effect of preventing a current that generates the magnetic field that cancels the magnetic field of the planar coil assembly.

[0235] In this way, according to the present embodiment, it is possible to provide the magnetic shielding structure of the planar coil array in which the magnetic field generated by the planar coil array can be shielded, and the strength of the magnetic field generated by each coil constituting the planar coil array can be suppressed with the simple configuration. <Ausführungsform 5>

[0236] Next, Fig. 14 is referred to. Fig. 14 is a diagram showing a configuration using a comb-tooth-shaped movable conductor and a plurality of planar coil assemblies.

[0237] As in A-1 of Fig. As shown in Fig. 14, when the planar coil array is applied to a displacement sensor, the movable conductor M10 is arranged near the planar coil array AR.

[0238] In A-2 of Fig. 14, a comb-tooth electrode is used as a movable conductor. In other words, a comb-tooth-shaped movable conductor M20 is used. The comb-tooth-shaped movable conductor M20 has comb-tooth elements CM1 to CM3.

[0239] Further, a plurality of planar coil assemblies AR-1 to AR-3 are provided. The planar coil assemblies AR-1 to AR-3 extend parallel to each other along the X direction, which is a predetermined direction, and are stacked at intervals in the Y direction orthogonal to the X direction.

[0240] Here the interval is not limited in size and can be an object with an insulator placed in between, as long as isolation is ensured.

[0241] For example, a barium titanate-based dielectric ceramic material can be used as the insulator.

[0242] Each of the planar coil assemblies AR-1 to AR-3 has the same number of planar coils. It is preferable that the planar coil assemblies AR-1 to AR-3 be arranged so that the spirals of the planar coils included in the planar coil assemblies overlap each other, and the directions of the currents flowing through the spirals are the same when viewed from the Y direction in a plan view.

[0243] The planar coil assembly AR-1 is arranged between the comb-tooth elements CM1 and CM2, and the planar coil assembly AR-2 is arranged between the comb-tooth elements CM2 and CM3. The planar coil assembly AR-3 is arranged below the comb-tooth element CM3.

[0244] In other words, the planar coil assemblies AR1 and AR2 are arranged to enclose the combtooth element CM2, and the planar coil assemblies AR2 and AR3 are arranged to enclose the combtooth element CM3.

[0245] The planar coil assemblies AR1 to AR3 are electrically connected by a signal line indicated by a dashed line. In other words, the planar coil assemblies AR1 to AR3 are connected in series between terminals A and B.

[0246] According to this configuration, when the movable conductor M20 is displaced, a variation in the inductance occurs in each planar coil array, and the characteristics of the electrical signal change in the same way. Accordingly, the change in the electrical characteristics is emphasized. Accordingly, the detection sensitivity of the displacement sensor can be further improved.

[0247] As described above, a configuration may be employed in which the plurality of planar coil assemblies AR-1 to AR-3 of the present invention are provided, and the planar coil assemblies AR-1 to AR-3 extend parallel to each other along the predetermined direction and are stacked at intervals in a direction orthogonal to the predetermined direction.

[0248] According to this configuration, when the movable conductor is displaced, a variation in the inductance occurs in each planar coil array, and the characteristics of the electrical signal change in the same way. Accordingly, the change in the electrical characteristics is emphasized. Accordingly, the detection sensitivity of the displacement sensor can be further improved.

[0249] In A-3 of Fig. 14, the magnetic shielding member 402 is disposed on the +Y side of, i.e., above, the planar coil assemblies AR1 to AR3 and the comb-tooth-shaped movable conductor M20. The magnetic shielding member 404 is disposed on the -Y side of, i.e., below, the planar coil assemblies AR1 to AR3 and the comb-tooth-shaped movable conductor M20. In other words, the magnetic shielding members 402 and 404 are arranged parallel to each other to enclose the planar coil assemblies AR1 to AR3 and the comb-tooth-shaped movable conductor M20 in the up-down direction.

[0250] As the magnetic shielding elements 402 and 404, the one in which Fig. 10 to Fig. 13 may be used. The magnetic shielding elements 402 and 404 form a magnetic shielding structure for the planar coil assemblies AR1 to AR3.

[0251] However, if the magnetic shielding members 402 and 404 are regarded as accessories subordinate to the planar coil assemblies AR1 to AR3 from another point of view, it can also be said that the planar coil assembly is constructed with the magnetic shielding members.

[0252] Both magnetic shielding members 402 and 404 are preferably used, and any one of the magnetic shielding members 402 and 404 may be used. In this case, since there is no comb-tooth element under the planar coil assembly AR3, that is, on a back surface of the planar coil, the magnetic field of the coil easily leaks. Accordingly, it is preferable to preferably provide the magnetic shielding member 404. <Ausführungsform 6>

[0253] Next, Fig. 15 is referred to. Fig. 15 is a diagram showing an arrangement example of magnetic shielding elements. In Fig. 15, planar coil assemblies AR10, 10' and a peripheral conductor 702 are arranged within a cylindrical movable conductor tube M30. Peripheral conductors 700 and 704 are arranged outside the movable conductor tube M30.

[0254] A magnetic shielding member 416 is provided between the movable conductor tube M20 and the peripheral conductor 700 arranged outside the movable conductor tube M20.

[0255] The magnetic shielding member 418 is provided between the planar coil assembly AR10 and the peripheral conductor 702 disposed within the movable conductor tube M30.

[0256] The magnetic shielding element 420 is provided between the planar coil assembly AR10' and the peripheral conductor 702 arranged within the movable conductor tube M30.

[0257] The magnetic shielding member 416 is provided between the movable conductor tube M20 and the peripheral conductor 704 arranged outside the movable conductor tube M20.

[0258] No magnetic shielding member is provided on the mating surfaces of the movable conductor tube M30 and the planar coil assemblies AR10 and AR10'. In some cases, current flows through the peripheral conductors 700, 702, and 704 due to the influence of the magnetic field generated by the planar coil assemblies AR10 and AR10', causing noise. Accordingly, the magnetic shielding members 416, 418, and 422 are disposed between each of the peripheral conductors 700, 702, and 704 and the planar coil assemblies AR10 and AR10' to suppress noise generation.

[0259] As the magnetic shielding members 416, 418 and 422, the magnetic shielding member provided in one of the Fig. 10 to Fig. 13. The magnetic shielding members 416, 418, and 422 form a magnetic shielding structure for the planar coil assemblies AR1 to AR3. A three-dimensional shape obtained by bending the planar coil assembly may be used as the magnetic shielding member. This point will be described later. <Ausführungsform 7>

[0260] In the present embodiment, a planar coil assembly having a three-dimensional shape is described. When a prior art coil having a three-dimensional shape is replaced with a flat plate-shaped planar coil assembly, layout may be difficult. With this in mind, in the present embodiment, an example is described in which a flexible printed circuit board, a flexible film-shaped board, or the like is used and bent to form the desired three-dimensional shape.

[0261] It will be Fig. 16 is referred to. Fig. Figure 16 is a diagram showing a structural example of a planar coil assembly having a three-dimensional shape and a direction of a generated magnetic field. Fig. 16, the same parts as those in the above-described drawings are designated by the same reference numerals. The following description describes an example using the flexible printed circuit board.

[0262] A-1 of Fig. Figure 16 shows the planar coil arrangement AR with the multilayer structure previously described in Fig. 5. A cross-sectional structure of the planar coil assembly AR shown in A-1 is shown in A-2 of Fig. 16. This cross-sectional structure is the same as the one shown on the left side of Fig. 6A is shown.

[0263] However, the present invention is not limited to the multi-layer structure, and for example, a planar coil arrangement may be used in which planar coils are arranged on the same layer as in Fig. 4, are arranged side by side.

[0264] As described above, the planar coil SU1 has a spiral shape in which the conductor 310 on an upper layer is wound left-handed with respect to the center.

[0265] The planar coil SU2 is arranged adjacent to the first planar coil SU1 in the X direction. The second planar coil SU2 has a spiral shape in which the conductor 314 is wound around the center on the same layer as the conductor of the planar coil SU1 in the same manner as the first planar coil, in other words, in the same direction as the first planar coil, and has a deviation of 180 degrees from the first spiral shape. In other words, the planar coils SU1 and SU2 have a relative positional relationship in which, when one spiral is rotated 180 degrees to the left or right, one spiral overlaps the other spiral.

[0266] The left-handed planar coils SU1 and SU2 form a planar coil on the upper layer.

[0267] The planar coils SU3 and SU4 on the lower surface are stacked on the planar coils SU1 and SU2 on the upper surface, respectively, so that they overlap each other in plan view. The planar coils SU3 and SU4 on the lower layer are right-handed planar coils, and the planar coils SU1 and SU2 on the upper layer are wound in opposite directions, that is, opposite spiral winding directions. In other words, the planar coils SU1 and SU3 have a relative positional relationship in which, when one spiral is reversed horizontally, one spiral overlaps the other spiral. The same applies to the planar coils SU2 and SU4.

[0268] The spirals of the planar coils SU2 and SU4 on the lower layer are deflected by 180 degrees from each other.

[0269] A center of the planar coil SU1 and a center of the planar coil SU3 are electrically connected by the center connection conductor DE1, and the center of the planar coil SU2 and the center of the planar coil SU4 are electrically connected by the center connection conductor DE2.

[0270] End portions of the planar coils SU3 and SU4 on the lower layer are electrically connected to each other by the end portion connecting conductor CN2.

[0271] Accordingly, the center of the planar coil SU1 and the center of the planar coil unit SU2 are electrically connected to each other via a path including the center connection conductor DE1, the planar coil SU3, the end portion connection conductor CN2, the planar coil SU4, and the center connection conductor DE2.

[0272] Here, the planar coils SU3 and SU4 on the lower layer are not limited to coil elements, but can be considered as components of an electrical path. That is, the end portions of the planar coils SU3 and SU4 on the lower layer are also components of the electrical path connecting the end portions of the planar coils SU1 and SU2 on the upper layer.

[0273] In other words, the first and second end portions of the first and second planar coils SU1 and SU2 are electrically connected to each other through the electrical path including the second, third and fourth connecting conductors DE1, DE2 and CN2 and the first to fourth planar coils SU1, SU2, SU3 and SU4.

[0274] Taking this point into account, the configuration of A-1 can be Fig. 16 may be referred to as a configuration in which the end portions of the first and second planar coils SU1 and SU2 are electrically connected to each other through the electrical path including the coils SU3 and SU4 on the lower layer when the planar coils SU1 and SU2 on the upper layer are the first and second planar coils in order from the left.

[0275] In the present embodiment, the flexible printed circuit board having flexibility and being able to bend is used as the printed circuit board 311.

[0276] As in A-2 of Fig. As shown in Fig. 16, the multilayer structure including the flexible printed circuit board 311, the conductors 310 and 314 formed on a front surface thereof, the conductors 314 and 316 formed on a rear surface thereof, the center connection conductors DE1 and DE2, and the end portion connection conductor CN2, that is, the planar coil array structure, is designated by reference numeral 321, and in the following description, the entire planar coil array structure is referred to as a flexible board 321. That is, the flexible board 321 includes the flexible board or base material 311 and the wiring or conductor patterns 310 to 316, DE1, DE2 formed of a conductor formed on the front surface, the rear surface, or the inside thereof.

[0277] In A-2 of Fig. 16, there is a region designated by the reference symbols UA, UB, UC, and UD. Each region is enclosed by a dashed ellipse. Each region forms a part of the coil and, more specifically, is a region in which a winding pattern constituting the coil is present. In the following description, the regions UA to UD are referred to as coil regions or coil pattern regions.

[0278] As shown in A-3 of Fig. 16, the flexible printed circuit board 321 generates the magnetic field BS7 to the left, the magnetic field BS8 to the right, and the magnetic field BS9 to the left. Since this point is discussed with reference to Fig. 6B, a detailed description of it is omitted.

[0279] As shown in A-4 of Fig. As shown in Figure 16, the flexible printed circuit board 321 is bent, thus forming a coil having a three-dimensional shape. Specifically, the three-dimensional shape is a cylindrical shape.

[0280] As in A-1 to A-3 of Fig. 16, the flat plate-shaped planar coil assembly AR is also the flexible printed circuit board 321 extending along the X direction, which is a predetermined direction, that is, along a horizontal direction.

[0281] The flexible printed circuit board 321 has an end portion on the -X side, i.e., a left end portion, and an end portion on the +X side, i.e., a right end portion. The left end portion may be referred to as one end portion in the X direction, which is the predetermined direction, and the right end portion may be referred to as the other end portion.

[0282] As in A-4 and A-5 of Fig. 16, the flexible printed circuit board 321 is bent so that one end portion and the other end portion of the flexible printed circuit board 321 are close to or in contact with each other in the X direction, which is the predetermined direction, thereby forming the cylindrical three-dimensional shape.

[0283] In the examples of A-4 and A-5 in Fig. 16, the end portions are close to each other but slightly spaced apart. The end portions can be brought into contact with each other, and a cross-sectional shape thereof can be a circle or an ellipse.

[0284] As shown in A-4 of Fig. As shown in Figure 16, the planar coil assembly with the three-dimensional shape subjected to bending is designated by a reference character AR-3D-1. When simply written as the planar coil assembly AR, it cannot be distinguished from a flat plate-shaped coil assembly, so the one with the three-dimensional shape is designated AR-3D. Reference character 1 at the end indicates a first example of the AR-3D.

[0285] As shown in A-5 of Fig. 16, a pair of wirings L40 and L10 and a pair of wirings L70 and L60 arranged close to each other extend in the same direction in the three-dimensional space.

[0286] Here, currents flow in the same direction in the pair of wires L40 and L10. Accordingly, magnetic fields J1 and J2 are generated in the same direction.

[0287] On the other hand, currents flow in the same direction in the pair of wirings L70 and L60, but the direction is opposite to the direction of the currents in wirings L40 and L10. Accordingly, the magnetic fields J3 and J4 become rightward magnetic fields.

[0288] Since the directions of magnetic fields J1 and J2 are the same, they do not cancel each other out, and thus a strong magnetic field can be generated. The same applies to magnetic fields J3 and J4.

[0289] Here, the wiring L40 is a wiring included in the coil pattern area UD, and is a linear wiring at an outermost portion located at a position closest to one end portion of the flexible printed circuit board 321.

[0290] The wiring L10 is a wiring included in the coil pattern area UA, and is a linear wiring at an outermost portion located at a position closest to the other end portion of the flexible printed circuit board 321.

[0291] The wiring L70 is a wiring included in the coil pattern area UC, and is a straight wiring located on a side opposite to the wiring L40 in the X direction, which is the predetermined direction, and extending in parallel to the wiring L40.

[0292] Further, the wiring L80 is a wiring included in the coil pattern area UB, and is a linear wiring located on a side opposite to the wiring L10 in the X direction, which is the predetermined direction, and extending in parallel to the wiring L10.

[0293] As shown in A-6 of Fig. As shown in Figure 16, a magnetic field obtained by combining the magnetic field BS8 shown previously in A-3 with the magnetic fields BS7 and BS9 is generated in the planar coil assembly AR-3D-1 formed of the cylindrical flexible printed circuit board 321. The magnetic field BS8 is a rightward magnetic field, and a magnetic field obtained by combining the magnetic fields BS7 and BS9 is a leftward magnetic field. The strength of each magnetic field is the same, and a strong magnetic field balanced on the left and right with respect to an axis for bending OP is generated. The axis for bending OP can be referred to as a central axis of the coil. Note that the axis for bending OP is a straight line extending from a front side of a paper surface to a back side of the paper surface.

[0294] As shown in A-6 of Fig. As shown in Figure 16, each magnetic field line of the magnetic field obtained by combining the magnetic field BS8 with the magnetic fields BS7 and BS9 is orthogonal to the bending axis OP. In other words, when the magnetic field lines intersect the bending axis OP, the magnetic field lines cross the bending axis OP from top to bottom at an angle of 90 degrees.

[0295] Furthermore, “orthogonal” is not restricted to 90 degrees and can be functionally satisfied as long as it is essentially orthogonal, and thus “orthogonal” is not strictly restricted.

[0296] A horizontally long coil CL in the prior art is shown in A-7 of Fig. 16. Magnetic fields BS100 and BS101 generated by the coil CL in the prior art are magnetic fields parallel to the central axis OP of the coil.

[0297] As described above, a direction of the magnetic field generated by the planar coil assembly AR-3D-1 shown in A-6 differs from Fig. 16, with respect to an axis for bending, that is, the center axis OP of the coil, from that of a prior art example shown in A-7. This point can be referred to as a feature of the planar coil assembly AR-3D-1 as the coil.

[0298] When the planar coil arrangement AR-3D-1 of Fig. 16 has a flat shape, the electrical connection of the planar coils is already completed. Thus, the flexible printed circuit board 321 can be manufactured only by bending. Accordingly, it is possible to provide the coil with the three-dimensional shape using the planar coil assembly, which can be manufactured inexpensively and easily.

[0299] In the planar coil arrangement AR-3D-1, as shown in A-6 of Fig. As shown in Figure 16, the strong magnetic field can be generated with good balance with respect to the axis for bending OP left and right.

[0300] Accordingly, for example, when the planar coil array AR-3D-1 is applied to a displacement sensor such as a stroke sensor, a displacement sensor with low noise, high detection sensitivity, in other words, high gain, is implemented.

[0301] Furthermore, since the planar coil assembly AR-3D-1 has a cylindrical shape similar to the horizontally long coil in the prior art, the planar coil assembly AR-3D-1 can be easily arranged near the movable conductor tube.

[0302] Furthermore, the AR-3D-1 planar coil assembly can be manufactured by bending a AR50 planar coil assembly with a simplified configuration and can have a compact shape overall. Therefore, an effect that the AR-3D-1 planar coil assembly can be easily arranged in a narrow space is also obtained. <Ausführungsform 8>

[0303] Next, Fig. 17 is referred to. Fig. Figure 17 is a diagram showing another structural example of the planar coil array with the three-dimensional shape and the direction of the generated magnetic field.

[0304] In the A-1 of Fig. In the planar coil assembly AR50 shown in Figure 17, three planar coils SU1, SU2, and SU1 are used as planar coils on an upper layer. Three planar coils SU3, SU4, and SU3 are used as planar coils on a lower layer.

[0305] A configuration of A-1 from Fig. 17 is a structure in which the planar coils SU1 and SU4 located at the right end are removed from the multilayer structure previously shown in Fig. 6B. The previously shown Fig. 6B can also be applied to a structure of A-1 of Fig. 17. A detailed description of the multilayer structure is omitted.

[0306] Also in the configuration of A-1 from Fig. 17, the left planar coil SU3 and the right planar coil SU4 thereof on the lower layer can be regarded as components of an electrical path connecting end portions of the planar coils SU1 and SU2 on the upper layer, respectively.

[0307] Here, the planar coils on the upper layer SU1, SU2 and SU1 are referred to as the first, second and third planar coils in order from the left.

[0308] The planar coil assembly AR50 has a configuration in which the end portions of the first and second planar coils SU1 and SU2 are electrically connected to each other through an electrical path including the third and fourth planar coils on the lower layer, and the second planar coil SU2 and the right third planar coil SU1 thereof are electrically connected through the end portion connecting conductor CN1 on the same layer.

[0309] Furthermore, the previously Fig. 6B shown magnetic field BS8 is drawn by being in A-1 of Fig. 17 is divided into BS8-1 and BS8-2. Similarly, the magnetic field BS9 is divided into BS9-1 and BS9-2.

[0310] Next, on A-2 from Fig. 17. As shown, a planar coil array AR-3D-2 has a wavy three-dimensional shape. When focusing on the first, second, and third planar coils SU1, SU2, and SU3 on the upper layer, each planar coil is folded back, and the planar coils SU1, SU2, and SU3 are stacked in the Y direction orthogonal to the X direction, that is, the up-down direction, which is a predetermined direction, to form the wavy cross-sectional structure.

[0311] When the viewing direction is changed, the wavy three-dimensional shape of the planar coil assembly AR-3D-2 has a three-dimensional shape in which the first, second, and third planar coils SU1, SU2, and SU1 on the upper layer overlap each other in a plan view viewed from the Y direction.

[0312] Considering the planar coils SU3, SU4, and SU3 on the lower layer, the planar coil array AR-3D-2 has the wavy three-dimensional shape in which the planar coil arrays SU1, SU3, SU4, SU2, SU1, and SU3 are stacked in this order from the top.

[0313] In the AR-3D-2 planar coil assembly, a strong magnetic field with good balance is generated with respect to the left and right bending axis OP. A left-sided magnetic field is a left-directed magnetic field generated by combining the magnetic fields BS7, BS9-1, and BS9-2. A right-sided magnetic field is a right-directed magnetic field generated by combining the magnetic fields BS8-1, BS8-2, and BS10.

[0314] Next, on A-3 from Fig. 17. As stated in A-3 of Fig. As shown in Fig. 17, a planar coil assembly AR-3D-3 has a roll-like three-dimensional shape in which the planar coil assembly AR50 is wound in a roll shape.

[0315] When focusing on the first, second, and third planar coils SU1, SU2, and SU1 on the upper layer, the planar coil assembly AR50 has a roll-shaped cross-sectional structure in which the planar coils SU1, SU2, and SU1 are stacked in the Y direction, that is, in the up-down direction.

[0316] When the viewing direction is changed, the roll-shaped three-dimensional shape of the planar coil assembly AR-3D-3 can be described as a three-dimensional shape in which the first, second, and third planar coils SU1, SU2, and SU1 on the upper layer overlap each other in the plan view from the Y direction. This point is common to the wavy three-dimensional shape indicated by A-2.

[0317] Considering the planar coils SU3, SU4, and SU3 on the lower layer, the planar coil assembly AR-3D-3 has the roll-like three-dimensional shape in which the planar coil assemblies SU1, SU3, SU1, SU3, SU4, and SU2 are stacked in this order from the top.

[0318] In the AR-3D-3 planar coil assembly, a strong magnetic field with good balance is generated with respect to the left and right bending axis OP. A left-sided magnetic field is a left-directed magnetic field generated by combining the magnetic fields BS9-2, BS9-1, and BS7. A right-sided magnetic field is a right-directed magnetic field generated by combining the magnetic fields BS10, BS8-1, and BS8-2.

[0319] The planar coil assembly AR-3D-2 and the planar coil assembly AR-3D-3 of Fig. 17 each have a flat shape, and the electrical connection of the planar coils is already completed. Thus, the flexible printed circuit board 321 can be manufactured only by bending. Accordingly, it is possible to provide the coil with the three-dimensional shape using the planar coil assembly, which can be manufactured inexpensively and easily.

[0320] In the planar coil arrangement AR-3D-2 and the planar coil arrangement AR-3D-3, as shown in A-2 and A-3 of Fig. As shown in Figure 17, the strong magnetic field can be generated with good balance with respect to the axis for bending OP left and right.

[0321] Accordingly, for example, when the planar coil assemblies AR-3D-2 and AR-3D-3 are applied to a displacement sensor such as a stroke sensor, a displacement sensor with low noise, high detection sensitivity, in other words, high gain, is implemented.

[0322] Furthermore, since the planar coil assemblies AR-3D-2 and AR-3D-3 have a small structure in which planar coils are stacked in a plan view, an effect that the planar coil assemblies AR-3D-2 and AR-3D-3 can be easily arranged in a narrow space is also obtained. <Ausführungsform 9>

[0323] Next, the displacement sensor is described. Fig. 18 is a diagram showing a detection principle of the displacement sensor. A displacement sensor 150 as the displacement sensor includes the coil CL1, which is fitted to the movable conductor M1 with a fitting length LT and whose inductance changes according to a displacement amount of the movable conductor M1, a sensor body 100, and a detection unit 7. The coil CL1 can be referred to as a resonance coil.

[0324] The sensor body 100 includes interface circuits IF1 and IF2. The interface circuit IF1 includes two terminals T1 and T2. A wiring harness 20 transmitting a current pulse signal IPL is connected to terminal T1, and a grounded wiring harness 20' is connected, for example, to terminal T2.

[0325] The interface circuit IF2 contains two terminals T3 and T4. One end of the coil CL1 is connected to terminal T3, and the other end of the coil CL1 is connected to terminal T4.

[0326] When the movable conductor M1 is displaced, the fitting length LT changes, and the frequency of the current pulse signal IPL changes accordingly. The detection unit 7 can detect the displacement amount of the movable conductor M1 by detecting a change in the frequency of the current pulse signal IPL.

[0327] The term “frequency” can be reformulated as electrical properties of an electrical signal in the broad sense.

[0328] Next, Fig. 19A is referred to. Fig. 19A is a diagram showing an example of a specific configuration of the displacement sensor. In Fig. 19A are parts corresponding to those in Fig. 18 are designated by the same reference numerals.

[0329] In Fig. 19A, an oscillation circuit 102 that generates the current pulse signal IPL is provided within the sensor body 100.

[0330] A resistor RD, one end of which is connected to a power supply potential V, is provided within the ECU 10. The resistor RD acts as a current and voltage converter 5. A voltage signal obtained from a common connection point between the power supply potential V and the resistor RD is input to the detection unit 7.

[0331] Next, Fig. 19B is referred to. Fig. 19B is a diagram showing an example of a change in the frequency of the current pulse signal according to a change in the fitting length between the movable conductor and the coil.

[0332] In Fig. In Figure 19B, the change in the fitting length LT between the movable conductor M1 and the coil CL1 is indicated by a dashed line. The frequency of the current pulse signal changes according to the change in the fitting length LT. By detecting the change in frequency, the displacement of the movable conductor M1 can be detected.

[0333] Next, Fig. 20 is referred to. Fig. 20 is a diagram showing an example of an overall configuration of a motorcycle in which the displacement sensor of the present invention is applied to a suspension.

[0334] By applying the displacement sensor of the present invention to the suspension, a stroke sensor that detects displacement of the suspension is implemented. Examples of the suspension may include a rear suspension and a front fork.

[0335] As in Fig. 20, the motorcycle 1 includes a front wheel 2, a rear wheel 3, a vehicle body main body 15 including a vehicle body frame 11 constituting a frame of the motorcycle 1, a handle 12, an engine 13, or the like.

[0336] Further, the motorcycle 1 includes a front fork 19 connecting the front wheel 2 to the vehicle body main body 15 on each of a left side and a right side of the front wheel 2. Further, the motorcycle 1 includes a rear suspension 22 connecting the rear wheel 3 to the vehicle body main body 15 on each of a left side and a right side of the rear wheel 3. Fig. 20 only the front fork 19 and the rear suspension 22, which are arranged on one side, are shown.

[0337] The rear suspension 22, for example, is a hydraulic suspension. Fig. 20 shows an external configuration of the rear suspension 22. The rear suspension 22 includes a vehicle body side fastening member 200, a wheel side fastening member 202, a coil spring 204, an outer tube 206, and a guide tube 208, which form a cylinder portion.

[0338] Next, Fig. 21 is referred to. Fig. 21 is a cross-sectional view showing an example of a cross-sectional structure of the Fig. 20 shown rear suspension. In Fig. 21, the previously mentioned with reference to Fig. 15 described configuration in the rear suspension 22. In Fig. 21 are the same components as those in Fig. 15 are designated by the same reference numerals. Fig. 15 described content can also be found on Fig. 21 can be applied.

[0339] Although the planar coil arrangement AR10 in Fig. 15 is used, however, the Fig. 16 described planar coil AR-3D-1 in Fig. 21 instead of AR10.

[0340] Although the movable conductor tube M30 in Fig. 15 is used, the outer tube 206, which forms the cylinder section, is further Fig. 21 is used instead of M30. In other words, the outer tube 206 acts as a movable conductor tube.

[0341] Although the peripheral conductors 700 and 704 in Fig. 15 are used, the guide tube 208, which forms the cylinder section, is further Fig. 21 is used instead of 700 and 704.

[0342] In the rear suspension 22 of Fig. 21, the guide tube 208 is disposed within the coil spring 204, and the outer tube 206 as a movable conductor tube is disposed within the guide tube 208. The planar coil assembly AR-3D-1 is disposed within the outer tube 206.

[0343] The magnetic shielding elements 416 and 422 of the present invention, which are shown in Fig. 11 to Fig. 13 are provided between the guide tube 208 and the outer tube 206 as the movable conductor tube.

[0344] Furthermore, the magnetic shielding elements 418 and 420 of the present invention shown in Fig. 11 to Fig. 13, are provided between the planar coil assembly AR-3D-1 and the peripheral conductor 702 extending along the central axis of the guide tube 208.

[0345] Here, the magnetic shielding elements 416 and 422 may be formed from a bent common magnetic shielding element. Since the planar coil assembly AR-3D-1 has a cylindrical shape, the magnetic shielding element is preferably also bent to have a shape corresponding to the three-dimensional shape of the planar coil assembly, i.e., a cylindrical cross-section. The same applies to the magnetic shielding elements 418 and 420. This makes it possible to effectively shield the planar coil assembly with the three-dimensional shape by bending.

[0346] Thus, a prior art coil component in the rear suspension 22 of the motorcycle 1 can be replaced, for example, with the planar coil assembly AR-3D-1 of the present invention. A flat, plate-shaped planar coil assembly that does not have a three-dimensional shape can be used.

[0347] The planar coil assembly of the present invention is easy to manufacture, and the planar coil assembly is much more cost-effective than the coil component in the prior art, and can also be reduced in size. Thus, a displacement sensor that is easy to manufacture, has a simplified configuration, and is inexpensive can be obtained.

[0348] In the coil component in the prior art which is long in the predetermined direction and previously described in A-7 of Fig. As shown in Figure 16, high costs and many man-hours are required to manufacture the coil component. Accordingly, by using the planar coil assembly of the present invention instead of the coil component in the prior art, the manufacturing process of the coil component can be simplified, and the cost of the coil can be significantly reduced. This also contributes to reducing the cost of a vehicle such as a motorcycle.

[0349] Furthermore, the rear suspension of Fig. 21, the magnetic shielding member is disposed at an appropriate position, and adverse influence on the peripheral conductor of the peripheral device or the like is also sufficiently reduced. Thus, the coil component employing the planar coil assembly can be used safely and securely.

[0350] The above description is summarized as follows.

[0351] A displacement sensor comprises the planar coil array AR according to the present invention and the detection unit 7 which detects a change in the electrical characteristics of the electrical signal generated according to the displacement amount of a movable conductive object and transmitted via the planar coil array.

[0352] Accordingly, the displacement sensor which is easy to manufacture, has a simplified configuration, and is inexpensive can be obtained.

[0353] If a through A-2 of Fig. 14 is used, the planar coil assembly AR-1 may be arranged between the combtooth element CM1 and the combtooth element CM2 in the combtooth structure of the object.

[0354] Thus, a stronger magnetic field can be generated and a displacement sensor with higher detection sensitivity can be implemented.

[0355] Further, the object may be a component of the suspension 22, and the displacement sensor may be the stroke sensor 150 that measures the displacement amount of the suspension by detecting electrical properties of an electrical signal that changes according to a relative positional relationship between the object and the planar coil array AR, for example, a frequency of an electrical signal or an inductance.

[0356] Accordingly, the stroke sensor which is easy to manufacture, has a simplified configuration and is inexpensive can be obtained.

[0357] In the above description, the motorcycle was described as an example, but the planar coil assembly of the present invention is also applicable to a three-wheeled vehicle, a four-wheeled vehicle, and the like is also applicable to a currently developed electric motor vehicle, and the type of the vehicle is not limited.

[0358] As described above, according to the present invention, it is possible to provide the planar coil assembly simplified in the configuration in which the plurality of planar coils are electrically connected and also includes a function as a low-loss path of the electrical signal.

[0359] The present invention is not limited to the embodiments as long as the functions and effects of the invention are demonstrated. Commercial applicability

[0360] The present invention is suitable for a planar coil arrangement that can be used in various applications. List of reference symbols 1 vehicle (motorcycle) 2 front wheel 3 rear wheel 5 current and voltage transformers 7 Detection unit 10 ECU (control unit, signal processing unit, electronic control unit) 11 Vehicle body frame 12 handle 13 Engine 15 Vehicle body main body 19 front fork 20, 20' connecting wire (wiring harness) 22 rear suspension (shock absorbers) 34 Microstrip line (high-frequency transmission path) 35 Current flowing along one direction in a planar coil arrangement 38, 47, 47' Current flowing through peripheral conductor (reverse current) 83 Conductor connecting centers of adjacent planar coils (center connecting conductor, arc-shaped wiring harness) 87 Conductor connecting centers of adjacent planar coils (center connecting conductor, bridge electrode, multilayer structure electrode and multilayer structure wiring) 100 sensor bodies 102 Oscillation circuit 150 stroke sensor as displacement sensor 200 vehicle body-side fastening element 202 wheel-side fastening element 204 coil spring 206 Outer tube (component of the shock absorber, movable conductor (detection conductor)) 208 guide tube 310, 314, 318, 324 front surface conductor of the printed circuit board (front surface wiring and upper layer wiring) 311 Board or base material (printed circuit board, rigid board, flexible circuit board, film-shaped flexible circuit board) 312, 316, 320, 326 rear surface conductor of the printed circuit board (rear surface wiring and lower layer wiring) 321 flexible circuit board 402, 404, 416, 418, 420, 422 magnetic shielding element 416, 418, 420, 422 magnetic shielding element 502, 504 object to be protected, peripheral conductor, electronic board (semiconductor board or the like) 501 Slot in predetermined direction 503 Slot perpendicular to predetermined direction 700, 702, 704 peripheral conductor arranged inside the outer tube AR, AR1-3, AR10 planar coil arrangement SU1 planar coil (planar coil unit) wound in a predetermined direction SU2 planar coil (planar coil unit) having the same winding direction as SU1 and has an angular deviation (deviation of 180 degrees in preferred example) M1, M10, M20, M30 conductor to be detected (detection conductor, movable conductor) CL, CL1 coil (sensor coil) BS1 to BS11 Direction of the magnetic field (magnetic flux) generated by the planar coil arrangement P1 to P4 wiring that forms the planar coil CN1, CN2 conductor (end section connecting wiring) connecting end sections on outer peripheral sides of adjacent planar coils F1 to F3 component of the end section connecting wiring VIAH through hole DE1 to DE4 through electrode (buried through conductor, interlayer connecting conductor) T1 to T4 connection IF1 ECU-side interface IF2 coil-side interface LT pass length QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2020 / 035968

[0006] JP 6450611B

[0006]

Claims

A planar coil assembly comprising:a first planar coil having a first spiral shape in which a first conductor is wound left-handed or right-handed around a first center; anda second planar coil having a second spiral shape in which a second conductor is wound on the same layer as the first conductor in the same manner as the first planar coil around a second center and has an angular deviation from the first spiral shape. The planar coil assembly of claim 1, further comprising:a third planar coil formed of a third conductor on a different layer from the first conductor and arranged to overlap the first planar coil in a plan view; anda fourth planar coil formed of a fourth conductor on the same layer as the third conductor and arranged to overlap the second planar coil in the plan view. The planar coil assembly of claim 2, wherein the third planar coil has a spiral shape in which the third conductor is wound around a third center in a direction opposite to the first planar coil, and the fourth planar coil has a spiral shape in which the fourth conductor is wound around a fourth center in a direction opposite to the second planar coil. A planar coil assembly according to claim 3, wherein the third and fourth planar coils are formed in a multi-layer structure according to a double-sided mounting technique for a printed circuit board or a multi-layer structure according to a multi-layer wiring technique for forming an interlayer insulating layer and a multi-layer wiring layer on a board. A planar coil assembly comprising:a plurality of the planar coil assemblies according to any one of claims 1 to 4, wherein the planar coil assemblies extend parallel to each other along a predetermined direction and are stacked at intervals in a direction orthogonal to the predetermined direction. A displacement sensor comprising: the planar coil assembly according to any one of claims 1 to 4; and a detection unit configured to detect a change in an electrical property of an electrical signal generated according to a displacement amount of a movable conductive object and transmitted via the planar coil assembly. The displacement sensor of claim 6, wherein the planar coil arrangement is arranged between a combtooth element and a combtooth element in a combtooth structure of the object. The displacement sensor according to claim 6, wherein the object is a component of a suspension, and the displacement sensor is a stroke sensor that measures a displacement amount of the suspension by detecting the electrical property of the electrical signal that changes according to a relative positional relationship between the object and the planar coil assembly.

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