JP2017150979A - Current measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify current measurement.SOLUTION: A coil conductor wire 241 is arranged on the top face of a first insulation layer D1. A connection pad 26 is formed on a y-axis negative side of an outside end 28 of the coil conductor wire 241. The coil conductive wire 241 extends in an inward direction from the outside end 28 while circling a number of times until it reaches a through-hole T12 at an inside end 30. A coil conductor wire 242 is arranged on the top face of a second insulation layer D2. The coil conductive wire 242 extends in an outward direction from an inside end 32 connected to the through-hole T12 while circling a number of times until it reaches a through-hole T23 at an outside end 34.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a current measuring device, and more particularly to a current measuring device formed on a substrate.

  Electrical facilities such as transformers, voltage converters, and frequency converters are provided in facilities such as substations in the power transmission and distribution system. In addition, power supply systems such as office buildings and factories are provided with a power supply system that supplies the distributed power to each room or each manufacturing site. This power supply system is provided with electrical equipment such as a transformer, a watt-hour meter, a relay, and a breaker.

  In such facilities where electric power is handled, the current flowing in the wiring of electrical equipment is measured for maintenance, inspection, and the like. For current measurement, a current measurement device using a Hall element, a coil, a CT (Current Transformer), or the like is widely used.

  Patent Document 1 below describes a current sensor formed using a printed circuit board as a current measuring device using a coil. In this current sensor, a coil surrounding the opening is formed around the opening opened in the printed circuit board. A wire to be measured is inserted through the opening, and a magnetic field based on a current flowing through the wire to be measured is detected by the coil. Patent Document 2 describes a high-voltage hot wire ammeter using a CT clamp. The CT clamp is divided into two C-shaped members. One end of one C-shaped member is rotatable about the one end of the other C-shaped member as an axis, thereby allowing the CT clamp to be opened and closed. The CT clamp is once opened and closed after receiving the high-voltage hot wire, and is attached to the high-voltage hot wire so as to surround the high-pressure hot wire in the closed state. And an electric current is measured based on the magnetic field induced in clamp CT by the electric current which flows into a high voltage | pressure hot wire.

JP 2011-141208 A JP 2005-172752 A

  Many current measuring devices are annular. In the annular current measuring device, it is necessary to once remove the conducting wire through which the current to be measured flows from the electrical device, pass the conducting wire through the current measuring device, and then attach the conducting wire to the electrical device again. Moreover, even if it is an electric current measuring device which has the clamp shape which can be opened and closed as described in patent document 2, when a conducting wire is provided in a narrow place, setting of the electric current measuring device becomes difficult.

  An object of the present invention is to easily perform current measurement.

  The present invention is formed on a substrate having a plurality of conductor pattern layers and a first layer that is one of the plurality of conductor pattern layers, and circulates a plurality of times from the outer end toward the inner end. And a conductor path extending from the inner end or the outer end of the coil conductor to the second layer that is another one of the plurality of conductor pattern layers. Features.

  Desirably, the second layer is formed in the second layer, and includes a second coil conductor that goes outward from the inner end toward the outer end, and the conductor path is provided on the inner side of the coil conductor. An end and the inner end of the second coil conductor, or an outer end of the coil conductor and an outer end of the second coil conductor, and the coil conductor is wound in an inward direction, The winding direction in which the second coil conducting wire is directed outward is the same as viewed from one surface side of the substrate.

  Desirably, one turn of the coil lead wire has a substantially quadrilateral shape in which the directions of two opposing sides are aligned in the extending direction of the lead wire through which the current to be measured flows. Over the circumference, the decrease in the length of the conductor in the extending direction is greater than the decrease in the length in the direction across the conductor.

  Preferably, it has a shield structure provided at least in the first layer and surrounding the coil conductor.

  According to the present invention, current measurement can be easily performed.

It is a figure which shows an electric current measurement device. It is a figure which shows the state which fractured | ruptured the cover part of the housing | casing of an electric current measurement device. It is a figure which shows typically the cross section in zx plane of a coil board. It is a figure which shows a 1st conductor pattern layer, a 1st insulating layer, a 2nd conductor pattern layer, and a 2nd insulating layer. It is a figure which shows a 3rd conductor pattern layer, a 3rd insulating layer, a 4th conductor pattern layer, and a 4th insulating layer. It is a figure which shows the lowest conductor pattern layer in case the number of the conductor pattern layers in which a coil conducting wire is formed is an odd number. It is a figure which shows 1st Example of a coil board. It is a figure which shows 2nd Example of a coil board. It is a figure which shows the example of the housing | casing of an electric current measurement device.

  FIG. 1 shows a current measuring device 10 according to an embodiment of the present invention. The current measuring device 10 detects a current flowing through the bus bar 12 by detecting a magnetic field appearing in the vicinity of the bus bar 12. The bus bar 12 is a conducting wire that transmits electric power, and is formed of a strip-shaped conductor. In FIG. 1, xyz coordinates are defined with the width direction of the bus bar 12 as the x-axis direction, the longitudinal direction of the bus bar 12 as the y-axis direction, and the direction perpendicular to the plate surface of the bus bar 12 as the z-axis direction.

  The casing 14 of the current measuring device 10 has a substantially rectangular parallelepiped shape in which an edge around the upper surface of the rectangular parallelepiped is obliquely chamfered. The current measuring device 10 is fixed to the bus bar 12 so that the bottom surface of the housing 14 overlaps the upper surface of the bus bar 12. For example, a double-sided adhesive tape that bonds the bottom surface of the housing 14 and the bus bar 12 is used to fix the current measuring device 10. Further, a band-like member or a string-like member that bundles the casing 14 and the bus bar 12 may be used. In the case 14 shown in FIG. 1, a binding recess 15 for engaging a band-like member or a string-like member is formed in a chamfered region at the edge around the upper surface.

  FIG. 2 shows a state in which the lid portion 16 of the housing 14 is broken. The housing 14 includes a bottom plate 18 and a lid 16. The housing 14 is formed of an insulator such as plastic resin. A coil plate 20 is fixed to the upper surface of the bottom plate 18. The lid portion 16 has a container shape that opens downward, and is fixed to the bottom plate 18 so as to cover the coil plate 20. On the inner surface of the lid portion 16, a deflection preventing projection 22 that prevents the lid portion 16 from being bent is formed. A coil plate pressing projection 23 that presses the edge of the coil plate 20 against the bottom plate 18 is formed on the inner surface of the side wall of the lid portion 16.

  FIG. 3 schematically shows a cross section of the coil plate 20 in the zx plane. The coil plate 20 is composed of a multilayer substrate. The coil plate 20 in this embodiment has an eight-layer structure, and includes a first conductor pattern layer L1, a first insulating layer D1, a second conductor pattern layer L2, a second insulating layer D2, a third conductor pattern layer L3, The third insulating layer D3, the fourth conductor pattern layer L4, and the fourth insulating layer D4 are stacked in this order in the z-axis direction. A spiral coil conductor 24 is formed on each conductor pattern layer. Each insulating layer is formed of an insulator such as a dielectric.

  FIG. 4 (L1) schematically shows the first conductor pattern layer L1 and the first insulating layer D1. A coil conductor 241 is disposed on the upper surface of the first insulating layer D1. A connection pad 26 is formed on the negative side of the outer end 28 of the coil conductor 241 in the y-axis direction. The connection pad 26 is a conductor pattern for connecting an external measurement conductor to the coil conductor 241.

  As will be described below, the coil conductor 241 turns inward from the outer end 28 three times and reaches the through hole T12 of the inner end 30 while facing inward. That is, in the first turn, the outer end 28 circulates in a substantially rectangular shape in the order of the negative x-axis direction, the positive y-axis direction, the positive x-axis direction, the negative y-axis direction, and the negative x-axis direction. To the reference line O. This position is a position inside the outer end 28 by the y-direction pitch dy. In addition, the substantially quadrangle | tetragon here means the shape approximated to the tetragon | quadrangle drawn by the line | wire with which both ends were open | released.

  The coil conducting wire 241 further circulates from the reference line O in a substantially rectangular shape in the order of the negative x-axis direction, the positive y-axis direction, the positive x-axis direction, the negative y-axis direction, and the negative x-axis direction. To. In the second turn, the x-direction pitch dx passes through the x-axis direction inner side and the y-direction pitch passes the y-axis direction inner side with respect to the first turn. Similarly, the coil conductor 241 reaches the inner end 30 by the third turn. In the third turn, the x-direction pitch dx passes the x-axis direction inner side and the y-direction pitch dy passes the y-axis direction inner side with respect to the second turn.

  The through hole T12 is a conductor path constituted by a cylindrical conductor and penetrates the insulating layer D1 up and down. The inner end 30 of the coil conductor 241 is connected to the through hole T12.

  Here, the structure of the coil conducting wire 241 has been described following the direction from the outer end 28 toward the inner end 30. When traced in the direction from the inner end 30 toward the outer end 28, the structure of the coil conductor 241 will be described as follows. That is, the coil conducting wire 241 turns outward from the inner end 30 and reaches the outer end 28 while turning around three times. In the second turn, the x-direction pitch dx passes the x-axis direction outside and the y-direction pitch passes the y-axis direction outside the first turn. In the third turn, the x-direction pitch dx passes the x-axis direction outside and the y-direction pitch dy passes the y-axis direction outside the second turn.

  The insulating layer D1 is provided with a plurality of shield through holes 36 surrounding the coil conductor 241. The shield through-hole 36 is formed of a cylindrical conductor. As shown in FIG. 3, the shielding through hole 36 includes the first insulating layer D1, the second conductive pattern layer L2, the second insulating layer D2, the third conductive pattern layer L3, the third insulating layer D3, It penetrates through the four conductor pattern layer L4 and the fourth insulating layer D4. The plurality of shield through holes 36 surround the coil conductors formed in each conductor pattern layer.

  FIG. 4 (L2) schematically shows the second conductor pattern layer L2 and the second insulating layer D2. A coil conductor 242 is disposed on the upper surface of the second insulating layer D2. The inner end 32 of the coil conductor 242 is connected to the through hole T12 that penetrates the first insulating layer D1.

  As will be described below, the coil conducting wire 242 wraps around the inner end 32 three times and reaches the through hole T23 in the outer end 34 in the outer direction. That is, the first round extends from the inner end 32 in the order of the x-axis negative direction, the y-axis positive direction, the x-axis positive direction, the y-axis negative direction, and the x-axis negative direction in a substantially rectangular shape. A reference line P indicating the x coordinate is reached. This position is a position outside the inner end 32 by the y-direction pitch dy.

  The coil conductor 242 further circulates from the reference line P in a substantially rectangular shape in the order of the negative x-axis direction, the positive y-axis direction, the positive x-axis direction, the negative y-axis direction, and the negative x-axis direction. To. In the second turn, the x-direction pitch dx passes the x-axis direction outside and the y-direction pitch dy passes the y-axis direction outside the first turn. Similarly, the coil conducting wire 242 reaches the through hole T23 of the outer end 34 by the third turn. In the third turn, the x-direction pitch dx passes the x-axis direction outside and the y-direction pitch dy passes the y-axis direction outside the second turn.

  The through hole T23 is a conductor path constituted by a cylindrical conductor and penetrates the insulating layer D2 up and down. The outer end 34 of the coil conducting wire 242 is connected to the through hole T23.

  Thus, the winding direction in which the coil conductor 242 in the second conductor pattern layer L2 circulates outward from the inner end 32 turns around the coil conductor 241 in the first conductor pattern layer L1 inward from the outer end 28. It is the same as the winding direction.

  FIG. 5 (L3) schematically shows the third conductor pattern layer L3 and the third insulating layer D3. A coil conductor 243 is disposed on the upper surface of the third insulating layer D3. The outer end 38 of the coil conducting wire 243 is connected to a through hole T23 that penetrates the second insulating layer D2.

  The coil conducting wire 243 has the same shape as the coil conducting wire 241 shown in FIG. 4 (L1) except for the innermost section in the x-axis direction reaching the inner end 40, and extends three times from the outer end 38. While going around, it goes inward and reaches the through hole T34 at the inner end 40. In the second turn, the coil conducting wire 243 passes the inside in the x-axis direction by the x-direction pitch dx and the inside in the y-axis direction by the y-direction pitch dy with respect to the first turn. In the third turn, the x-direction pitch dx passes the x-axis direction inner side and the y-direction pitch dy passes the y-axis direction inner side with respect to the second turn. The inner end 40 is located at a position shifted to the y-axis positive direction side from the inner end 30 of the coil conducting wire 241 shown in FIG. 4 (L1). This is for arranging the through hole T12 and the through hole T34 apart from each other.

  The through hole T34 is a conductor path constituted by a cylindrical conductor and penetrates the insulating layer D3 vertically. The inner end 40 of the coil conducting wire 243 is connected to the through hole T34.

  FIG. 5 (L4) schematically shows the fourth pattern layer L4 and the fourth insulating layer D4. A coil conductor 244 is disposed on the upper surface of the fourth insulating layer D4. The inner end 42 of the coil conducting wire 244 is connected to a through hole T34 that penetrates the third insulating layer D3.

  The coil conductor 244 has the same shape as the coil conductor 242 shown in FIG. 4 (L2) except for the innermost section in the x-axis direction extending from the inner end 42, and extends three times from the inner end 42. While going around, it reaches the through hole T41 at the outer end 44 in the outward direction. The inner end 42 is located at a position shifted to the y-axis positive direction side from the inner end 32 of the coil conducting wire 242 shown in FIG. 4 (L2). This is for arranging the through hole T12 and the through hole T34 apart from each other. In the second turn, the coil conducting wire 244 passes outside in the x-axis direction by the x-direction pitch dx and outside in the y-axis direction by the y-direction pitch dy with respect to the first turn. In the third turn, the x-direction pitch dx passes the x-axis direction outside and the y-direction pitch dy passes the y-axis direction outside the second turn.

  The through hole T41 is a conductor path constituted by a cylindrical conductor, and penetrates the conductor pattern layer L4, the insulating layer D3, the conductor pattern layer L3, the insulating layer D2, the conductor pattern layer L2, and the insulating layer D1. The outer end 44 of the coil conductor 244 is connected to the through hole T41.

  As shown in FIG. 4 (L1), the through hole T41 is connected to the connection pad 46 provided in the first conductor pattern layer L1. The connection pad 46 is a conductor pattern for connecting an external measurement conductor to the coil conductor 244.

  With such a configuration, the four coil conductors 241 to 244 are connected in series to form one current detection coil. The winding directions (winding directions) of the four coil conductors 241 to 244 are the same, and the coil conductor 241 is clockwise when viewed from the top surface of the coil plate 20 if the outer end 28 of the coil conductor 241 is the winding start end.

  In addition, although the case where the x direction pitch and the y direction pitch were made the same about each round was demonstrated above, the x direction pitch and the y direction pitch may differ for every round.

  In the above description, the number of turns of the coil conductor formed on each conductor pattern layer is three. However, the number of turns of the coil conductor is arbitrary for ease of understanding of the structure. The shape of one round of the coil conducting wire may be a shape that approximates other polygons, circles, ellipses, etc. in addition to a substantially square shape.

  In the above description, the structure in which the fourth insulating layer D4 is provided under the fourth conductor pattern layer L4 has been described. However, since the fourth conductor pattern layer L4 is fixed to the lower surface of the third insulating layer D3, The insulating layer D4 is not necessarily provided.

  Next, the operation of the current measuring device will be described. A pair of measuring conductors are connected to the two connection pads of the coil plate and are drawn out from the casing of the current measuring device. A pair of measuring conductors is connected to a measuring device.

  When a current flows through the bus bar 12 shown in FIG. 1, a magnetic field surrounding the bus bar 12 is generated in the zx plane. Thus, in addition to the basic magnetic field surrounding the bus bar 12, a singular magnetic field having a component perpendicular to the upper and lower surfaces of the bus bar 12 is also generated. The current measuring device 10 according to the present embodiment mainly detects a singular magnetic field.

  The singular magnetic field is linked to the four coil conductors 241 to 244 shown in FIGS. 4 and 5, and an induced electromotive force is generated in each coil conductor due to the singular magnetic field. The winding directions of the coil conducting wires 241 to 244 are the same, and these coil conducting wires are connected in series. Therefore, the induced electromotive force generated in each coil conductor is added with the same polarity, and a detection voltage in which the induced electromotive force generated in each coil conductor is added is generated in the connection pads 26 and 46. The magnitude of the detection voltage increases as the current flowing through the bus bar increases, and decreases as the current flowing through the bus bar decreases. The measuring device obtains the current flowing through the bus bar based on the detected voltage.

  The current measuring device is arranged close to the bus bar as an electric wire, and detects the current flowing through the bus bar. Therefore, since it is not necessary to penetrate the bus bar, current measurement is simplified. In addition, even when the space around the bus bar is narrow, such as when the bus bar is arranged in a gap between other members, it is easy to secure an installation space for the current measuring device.

  In addition, since the second insulating layer, the third conductor pattern layer, the third insulating layer, the fourth conductor pattern layer, and the fourth insulating layer D4 are provided with shield through holes, current measurement is performed from other electrical devices. The influence of noise electromagnetic waves arriving at the device is reduced. In addition, when the influence of noise electromagnetic waves does not become a problem, it is not necessary to provide a shielding through hole.

  In the above description, the structure in which four conductor pattern layers are provided and the coil conductors are formed in each conductor pattern layer has been described, but the number of coil conductors is arbitrary. When the number of conductor pattern layers on which the coil conductor is formed is an odd number, the bottom conductor pattern layer is connected to the through hole connected to the inner end of the coil conductor on the upper layer and the connection pad on the top layer. A conductive wire pattern connecting the through holes is formed. For example, when the coil conductor is formed in each of the first conductor pattern layer L1 to the third conductor pattern layer L3 and no coil conductor is formed in the fourth conductor pattern layer L4, the fourth conductor pattern layer L4 includes As shown in FIG. 6, a conductive wire 48 is provided to connect between the through hole T34 and the through hole T41.

  Further, the through holes T12, T23, and T34 shown in FIGS. 3 and 4 are provided in the first conductor pattern layer L1, the first insulating layer D1, the second conductor pattern layer L2, the second insulating layer D2, and the third conductor. Although not penetrating the pattern layer L3, the third insulating layer D3, the fourth conductor pattern layer L4, and the fourth insulating layer D4, each through hole has the first conductor pattern layer L1, the first insulating layer D1, and the second conductor. The pattern layer L2, the second insulating layer D2, the third conductor pattern layer L3, the third insulating layer D3, the fourth conductor pattern layer L4, and the fourth insulating layer D4 may be penetrated.

  FIG. 7 shows a first embodiment of the coil plate. In the first type coil plate 50, the conductor pattern layers and the insulating layers are alternately stacked. FIG. 7A shows the uppermost conductive pattern layer 52 and the uppermost insulating layer 54. FIG. 7B shows the lowermost conductor pattern layer 56 and the lowermost insulating layer 58.

  As shown in FIG. 7A, the coil conducting wire 60 turns 39 times in a substantially square shape from the outer end 62 inward in the clockwise direction, and the inner end 64 is connected to the through hole Ta. As shown in FIG. 7B, the inner end 68 of the coil conductor 66 is connected to the through hole Tb. The coil conducting wire 66 turns 39 times in a substantially square shape clockwise from the inner end 68, and the outer end 70 is connected to the through hole Tc. In the coil conductor formed in each conductor pattern layer, the pitch in the x direction and the pitch in the y direction are equal. When the first-type coil plate 50 is constituted by three or more conductor pattern layers and insulating layers, the even-numbered coil conductors have the same shape as in FIG. 7B, and the odd-numbered coil conductors are , Has the same shape as FIG. The line width of the coil conducting wire 66 is, for example, 0.05 mm to 2 mm. The pitch in the x direction and the pitch in the y direction are also 0.05 mm to 2 mm. The pitch in the x direction and the pitch in the y direction may be approximately the same as the line width of the coil conductor 66.

  The coil conductors formed in each conductor pattern layer are surrounded by a plurality of shield through holes 36 that vertically penetrate the first type coil plate 50.

  FIG. 8 shows a second embodiment of the coil plate. In the second type coil plate 72, conductor pattern layers and insulating layers are alternately stacked. FIG. 8A shows the uppermost conductive pattern layer 74 and the uppermost insulating layer 76. FIG. 8B shows the lowermost conductor pattern layer 78 and the lowermost insulating layer 80.

  As shown in FIG. 8 (a), the coil conductor 82 turns 39 times in a substantially square shape from the outer end 84 inward in the clockwise direction, and the inner end 86 is connected to the through hole Td. As shown in FIG. 8B, the inner end 90 of the coil conductor 88 is connected to the through hole Te. The coil conducting wire 88 turns 39 times in a substantially square shape clockwise from the inner end 90, and the outer end 92 is connected to the through hole Tf.

  In the coil conductor formed in each conductor pattern layer, the y-direction pitch is larger than the x-direction pitch. That is, one turn of each coil lead wire has drawn a substantially square shape in which the directions of the two opposing sides are aligned with the extending direction of the bus bar, and the direction crossing the bus bar from one turn on the outside to one turn on the adjacent inner side. The reduction in the length of the bus bar in the extending direction is larger than the reduction in the length of the bus bar. Alternatively, the increase in the length of the bus bar in the extending direction is greater than the increase in the length in the direction across the bus bar from one inner circle to one adjacent outer circle.

  When the second-type coil plate 72 is composed of three or more conductor pattern layers and insulating layers, the even-numbered coil conductors have the same shape as in FIG. 8B, and the odd-numbered coil conductors are , Has the same shape as FIG.

  In the first type coil plate 50 shown in FIG. 7, the y-direction pitch of the coil conductor is smaller than that of the second type coil plate 72 shown in FIG. Therefore, the first type coil plate 50 has a larger area (detection area) through which the magnetic flux passes than the second type coil plate 72, and the detection sensitivity becomes higher.

  On the other hand, in the 2nd type coil board 72, the y direction pitch of a coil conducting wire is larger than the x direction pitch. Accordingly, the tendency of the interlinkage magnetic flux per round to become smaller toward the inside is stronger than that of the first type coil plate 50, and the detection sensitivity is lower than that of the first type coil plate 50. The current measurement device does not always have a better current measurement state as the detection sensitivity is higher. For example, when the detection area is increased, the detected noise increases and the measurement accuracy may be reduced.

  Therefore, the second type coil plate 72 may be used when the current flowing through the bus bar is sufficiently large, or when the current flows in a concentrated manner at the center of the bus bar. Busbars often get hot on the edges on both sides and often have higher resistivity near the edges on both sides. In this case, the current density near the center is higher than that near the edges on both sides of the bus bar. In such a state, the effect of reducing the noise by reducing the detection area is greater than the effect of increasing the detection sensitivity by increasing the detection area of the coil conductor. In this case, the measurement accuracy of the second type coil plate 72 in which the coil conducting wire circulates in a narrow area near the center of the bus bar may be higher than that of the first type coil plate 50 in which the coil conducting wire circulates uniformly. .

  In addition, the same type of coil conducting wire (first type coil conducting wire) as that used for the first type coil plate 50 and the same type of coil conducting wire (second type) as that used for the second type coil plate 72 are used. Type coil conducting wire). That is, a coil conductor of a certain conductor pattern layer may be a first type coil conductor, and a coil conductor of another conductor pattern layer may be a second type coil conductor.

  FIG. 9 shows an example of the casing of the current measuring device. FIG. 9 is a diagram when the current measuring device 100 is viewed from the bus bar side. An electric wire engaging portion 95 is formed on the bottom surface 94 of the casing of the current measuring device 100. The electric wire engaging portion 95 is a portion protruding from the bottom surface 94, and is formed with a recess for receiving a columnar bus bar. In the example shown in FIG. 9, three electric wire engaging portions 95 are arranged in the longitudinal direction. The recess of the wire engaging portion 95 is shaped according to the shape of the surface of the bus bar. The current measuring device 100 is fixed to the bus bar so that the bus bar is received in the recess of the wire engaging portion 95. For fixing the current measuring device 100, a band-like or string-like rubber may be used. When the bus bar is received by the electric wire engaging portion 95 and the bus bar is engaged, fluctuation of the current measuring device 100 with respect to the bus bar is suppressed.

10,100 Current measuring device, 12 busbar, 14 housing, 15 binding recess, 16 lid, 18 bottom plate, 20, 50, 72 coil plate, 22 deflection preventing projection, 23 coil plate pressing projection, 24, 241-244, 60, 66, 82, 88 Coil conductor, 26, 46 Connection pad, 28, 34, 38, 44, 62, 70, 84, 92 Outer end, 30, 32, 40, 42, 64, 68, 86,90 Inner edge, 36 Shielding through hole, 48 Conductor, 52,74 Top conductor pattern layer, 54,76 Top insulation layer, 56,78 Bottom conductor pattern layer, 58,80 Bottom insulation layer , 94 bottom surface, 95 electric wire engaging part.

Claims (4)

A substrate having a plurality of conductor pattern layers;
A coil conductor formed in the first layer, which is one of the plurality of conductor pattern layers, and directed inward while rotating around a plurality of times from the outer end toward the inner end;
A conductor path from the inner end or the outer end of the coil conductor to the second layer which is another one of the plurality of conductor pattern layers;
A current measuring device comprising: The current measuring device according to claim 1,
The second layer is formed in the second layer, and includes a second coil conductor that goes outward while turning around the inner end toward the outer end multiple times.
The conductor path connects between the inner end of the coil conductor and the inner end of the second coil conductor, or between the outer end of the coil conductor and the outer end of the second coil conductor,
The current measuring device, wherein the winding direction in which the coil conducting wire is directed inward and the winding direction in which the second coil conducting wire is directed in the outward direction are the same as viewed from one surface side of the substrate. In the current measuring device according to claim 1 or 2,
One round of the coil conductor wire is drawn in a substantially quadrangle in which the directions of two opposing sides are aligned in the extending direction of the conductor wire through which the current to be measured flows.
A current measuring device characterized in that a decrease in length in the extending direction of the conductor is greater than a decrease in length in a direction crossing the conductor from one outer circle to one adjacent inner circle. In the current measuring device according to any one of claims 1 to 3,
A current measuring device having a shield structure provided at least in the first layer and surrounding the coil conductor.

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