JP7061421B2 - Magnetic sensor, sensor head and current sensor - Google Patents

Description

The present invention relates to a magnetic sensor, a sensor head and a current sensor.

As the above-mentioned current sensor, for example, the penetration type non-contact current sensor described in Patent Document 1 is known. The current sensor described in Patent Document 1 comprises an annular exciting core and an exciting coil wound around the exciting core to form a fluxgate element (magnetic sensor). Then, an electric signal obtained from the current or voltage flowing through the exciting coil is passed through the feedback coil wound outside the exciting coil, and a current signal is obtained from the current flowing through the feedback coil.

As the above-mentioned excitation core, it is conceivable to use a thin band-shaped magnetic material such as amorphous in order to improve the performance and reduce the cost. In such a case, a method of creating an excitation core by stacking the thin band-shaped magnetic material in several layers in a form of winding the thin band-shaped magnetic material a plurality of times is generally adopted.

Japanese Unexamined Patent Publication No. 2007-057294

However, such an exciting core cannot be used in a split clamp type non-contact current sensor. This is because if the excitation core composed of the thin band-shaped magnetic material is divided, the performance as the excitation core is lost. The first factor is the problem of mechanical strength. When the excitation core around which the thin band-shaped magnetic material is wound is divided, the cross section thereof is only a few layers of the thin band-shaped magnetic material, and the cross section of each layer is linear. Therefore, when it is adopted for the split clamp type non-contact current sensor, there arises a problem that the mechanical strength of the thin band-shaped magnetic material cannot withstand the opening / closing operation and causes a contact failure immediately.

The second factor is the problem of reproducibility of current measurements. As described above, since there are only a few layers of linear magnetic material in the cross section of the divided excitation core, the cross section is used in the opening / closing operation of the clamp portion of the split clamp type non-contact current sensor that employs this. The contact between the magnetic materials of the above is substantially a line contact. This means that the contact area between the magnetic materials is small. In such a case, it becomes difficult to obtain the reproducibility of the magnetic coupling at the contact portion due to the opening and closing of the clamp portion, and as a result, the problem that the reproducibility of the current measured value cannot be obtained also arises.

Under these circumstances, there is a problem that a thin band-shaped magnetic material cannot be adopted for the exciting core structure of the split clamp type non-contact current sensor.

The present invention has been made in view of the above background, and an object of the present invention is to provide a magnetic sensor, a sensor head, and a current sensor that can adopt a thin band-shaped magnetic material as a split clamp type excitation core.

In order to solve the above-mentioned problems, the magnetic sensor of the present invention covers both sides of a band-shaped magnetic material formed in an annular shape by overlapping both ends in the thickness direction and contacting each other, respectively. The second insulating layer, the first and second conductive patterns provided on the first and second insulating layers, and the through holes penetrating the first and second insulating layers are filled with the first and second insulating patterns. A filled conductive portion connecting between the second conductive patterns is provided, and the first and second conductive patterns and the filled conductive portion are provided so as to form a winding around the band-shaped magnetic material. It is characterized by being.

Further, the first insulating layer is provided so as to cover one end of the strip-shaped magnetic material in the band length direction and expose the other end, and the second insulating layer is made of the strip-shaped magnetic material. The strip-shaped magnetic material is provided so as to cover the other end in the band length direction and expose one end, and the strip-shaped magnetic material is overlapped with the portions exposed from the first and second insulating layers in contact with each other. You may be.

Further, the first and second insulating layers are provided with a protruding portion protruding in the band width direction of the strip-shaped magnetic material, and a pair of electrodes are provided at the tip of the protruding portion, and the first and first are provided. Any one of the two conductive patterns may be provided so as to connect both ends of the winding and the pair of electrodes.

Further, a third and fourth insulating layers that cover the first and second conductive patterns, respectively, may be further provided.

The sensor head of the present invention for solving the above-mentioned problems is further provided with the above-mentioned magnetic sensor and a reinforcing body made of a non-magnetic material, in which both ends are overlapped in the thickness direction and contacted to form an annular shape, and the above-mentioned reinforcement is provided. The body is characterized in that both ends are detachably provided and the magnetic sensor is provided on the reinforcing body.

Further, it is composed of a band-shaped first collector and a second collector, and both ends of the first collector and the second collector are in contact with each other to form an annular shape, which is arranged inside or outside the reinforcing body. A porcelain collector and a feedback coil wound around the porcelain collector may be provided.

The current sensor of the present invention for solving the above problems is characterized by comprising the sensor head and a current detecting means for detecting a current flowing through an object to be measured penetrated by the band-shaped magnetic material. ..

As described above, according to the invention of claim 1, both ends of the band-shaped magnetic material are overlapped and in contact with each other in the thickness direction. As a result, a sufficient contact area can be maintained for the opening / closing operation of the strip-shaped magnetic material, so that the thin strip-shaped magnetic material can be adopted as the clamp-type excitation core.

It is a block diagram which shows the non-contact type current sensor of this invention in 1st Embodiment. FIG. 3 is a schematic cross-sectional view taken along the line AA of the sensor head of FIG. It is a schematic top view of a magnetic sensor. FIG. 3 is a schematic cross-sectional view taken along the line BB of FIG. FIG. 3 is a schematic cross-sectional view taken along the line CC of FIG. It is a figure for demonstrating the conductive pattern provided on the 1st insulating layer shown in FIGS. 4 and 5. It is a figure for demonstrating the conductive pattern provided on the 2nd insulating layer shown in FIGS. 4 and 5. It is a perspective view of the magnetic sensor and the reinforcing body shown in FIG. 1 at the time of clamping. It is a side view of the magnetic sensor and the reinforcing body shown in FIG. It is a perspective view of the magnetic sensor and the reinforcing body shown in FIG. 1 at the time of non-clamping. 8 is an exploded perspective view of the reinforcing body shown in FIGS. 8 to 10. It is the schematic of the sensor head shown in FIG. 1 at the time of non-clamping. It is a schematic side view of the reinforcing body shown in FIG. 1 at the time of clamping. It is a schematic side view of the reinforcing body shown in FIG. 1 at the time of non-clamping. It is a schematic side view of the reinforcing body and a magnetic sensor shown in FIG. 1 at the time of clamping. It is a schematic side view at the time of non-clamping of the reinforcing body and a magnetic sensor shown in FIG. 1 at the time of non-clamping. It is a schematic side view which shows the excitation core at the time of clamping in the modification. It is a schematic side view which shows the excitation core at the time of non-clamping in the modification. It is a schematic side view which shows the reinforcing body at the time of clamping in the modification. It is a schematic side view which shows the reinforcing body at the time of non-clamping in the modification. It is a schematic side view which shows the reinforcing body at the time of clamping in the modification. It is a schematic side view which shows the reinforcing body at the time of non-clamping in the modification. It is a side view of the excitation core at the time of clamping in 2nd Embodiment. It is sectional drawing of the magnetic sensor in 3rd Embodiment. It is a schematic top view of the magnetic sensor shown in FIG. 24.

(First Embodiment)
An embodiment of the non-contact type current sensor of the present invention will be described with reference to the drawings. Note that FIG. 1 shows a state in which only a part of the core portions 20L and 20R is wound around the feedback coil 7 in order to avoid complicating the figure, but the feedback coil 7 is actually along the circumferential direction of the core portions 20L and 20R. It is common to wind the whole.

The current sensor 1 includes a sensor head 2 and a current detection circuit 10 as a current detection means. As shown in FIGS. 1 and 2, the sensor head 2 includes an annular magnetic sensor 3, an annular reinforcing body 4A that reinforces the magnetic sensor 3, and magnetic collectors provided inside and outside the magnetic sensor 3. A case (not shown) accommodating the inner magnetometer 5 and the outer magnetometer 6, the magnetic sensor 3, the reinforcing body 4A, the inner magnetometer 5 and the outer magnetometer 6, and a feedback coil 7 wound around a case (not shown). , Is equipped. An object 8 to be measured, such as an electric wire, is passed through the center of the magnetic sensor 3.

Further, the current detection circuit 10 includes an excitation circuit 11, a detection circuit 12, an LPF circuit 13, an amplifier circuit 14, a feedback circuit 15, and an I / V circuit 16. The exciting coil 35 included in the magnetic sensor 3, which will be described later, is connected to the exciting circuit 11 and is excited in an alternating current by an alternating current. The exciting voltage or exciting current of the exciting coil 35 changes due to the action of the current flowing through the object 8 to be measured (hereinafter referred to as the measured current). The detection circuit 12 detects a change in the exciting voltage or the exciting current, and passes through the LPF circuit 13 to obtain a signal proportional to the measured current.

Subsequently, this signal is amplified by the amplifier circuit 14 to generate a current flowing through the feedback coil 7 via the feedback circuit 15. A magnetic field is generated inside the feedback coil 7 by the current flowing through the feedback coil 7, and as a result, magnetic flux is generated in the band-shaped magnetic body 31, the inner magnetic collector 5, and the outer magnetic collector 6 included in the magnetic sensor 3 described later. The direction of the winding of the feedback coil 7 is such that the magnetic flux due to the current flowing through the feedback coil 7 cancels the magnetic flux generated by the measured current. Therefore, with this configuration, the magnetic flux of the band-shaped magnetic body 31, the inner magnetic collector 5, and the outer magnetic collector 6 inside the feedback coil 7 becomes almost zero, and the current flowing through the feedback coil 7 is proportional to the measured current. The current flowing through the 7 is converted into a current voltage by the I / V circuit 16 to obtain an output voltage which is an estimated value of the final measured current.

Next, the configuration of the magnetic sensor 3 will be described below with reference to FIGS. 3 to 7. The magnetic sensor 3 includes a band-shaped magnetic body 31, first and second flexible substrates 32 and 33 (FIG. 4 and the like) sandwiching the band-shaped magnetic body 31 between them, and a filling conduction portion 34 (FIG. 3). , It is provided in a flexible thin band shape. The band-shaped magnetic material 31 is made of a soft magnetic material, and has, for example, a thin band shape (ribbon shape) having a thickness of 100 μm or less and is flexible.

Similarly, the first and second flexible substrates 32 and 33 have a thin band shape and are flexible. The filled conductive portion 34 that conducts between the first and second conductive patterns 323 and 333, which will be described later, and the first and second conductive patterns 323 and 333 formed on the first and second flexible substrates 32 and 33. As a result, an exciting coil 35 (winding) wound around the band-shaped magnetic material 31 is formed.

As shown in FIG. 4, the first flexible substrate 32 includes a first insulating layer 321, a first adhesive layer 322, a first conductive pattern 323, a third insulating layer 324, and a third adhesive layer 325. It is equipped with. The first insulating layer 321 covers one of both sides of the strip-shaped magnetic material 31 and is composed of a well-known insulating member such as polyimide. As shown in FIG. 6, the first insulating layer 321 is a pair of a covering portion 321A which is long in the band length direction and which covers the band-shaped magnetic material 31, and an exciting coil 35 which protrudes from the covering portion 321A in the band width direction and is described later. It has an electrode forming portion 321B (protruding portion) on which the electrode 36 of the above is formed, and is formed in a substantially T shape.

As shown in FIG. 4, the covering portion 321A is provided so as to cover one end of the band-shaped magnetic material 31 in the band length direction and expose the other end. As shown in FIG. 6, a plurality of pairs of through holes 321C arranged in the band width direction are formed in the covering portion 321A by arranging them in the band length direction. The pair of through holes 321C are provided so that the band-shaped magnetic material 31 is located between them.

As shown in FIG. 4, the first adhesive layer 322 is provided between the first insulating layer 321 and the band-shaped magnetic material 31 or the second flexible substrate 32, and adheres to each other. As shown in FIG. 6, the first conductive pattern 323 is formed by etching a copper foil on the surface of the first insulating layer 321 on the side away from the band-shaped magnetic material 31. The first conductive pattern 321 is formed in a line shape connecting between a pair of through holes 321C arranged in the band width direction. In the first conductive pattern 321, by connecting a plurality of pairs of through holes 321C to each other, a plurality of lines along the band width direction are formed side by side in the band length direction.

Further, the first conductive pattern 323 connects a through hole 321C provided on the electrode forming portion 321B side with respect to the band-shaped magnetic body 31 located at both ends in the band length direction and a pair of electrodes 36. It is formed in a line shape. The pair of electrodes 36 are formed by applying electroless gold plating to the tip of the electrode forming portion 321B. The pair of electrodes 36 become both ends of the exciting coil 35 and are connected to the exciting circuit 11 and the detection circuit 12.

The third insulating layer 324 is provided with the same size and shape as the first insulating layer 321 and is provided so as to sandwich and cover the first conductive pattern 323 with the first insulating layer 321. As shown in FIGS. 3 and 5, the third insulating layer 324 is formed with exposed holes 324A that expose the pair of electrodes 36. As shown in FIG. 4, the third adhesive layer 325 adheres between the first insulating layer 321 and the third insulating layer 324.

As shown in FIG. 4, the second flexible substrate 33 includes a second insulating layer 331, a second adhesive layer 332, a second conductive pattern 333, a fourth insulating layer 334, and a fourth adhesive layer 335. I have. The second insulating layer 331 covers both sides of the strip-shaped magnetic material 31 and is made of a well-known insulating member such as polyimide. As shown in FIG. 7, the second insulating layer 331 includes a covering portion 331A that is long in the band length direction and covers the band-shaped magnetic material 31, and an electrode forming portion 331B that protrudes from the covering portion 331A in the band width direction. It has a substantially T-shape.

The covering portion 331A is provided so as to cover the other end portion of the strip-shaped magnetic material 31 in the band length direction and to expose the other end portion. The covering portion 331A is provided with a through hole 331C at a position facing the through hole 321C provided in the covering portion 321A. That is, in the covering portion 321A, a pair of through holes 331C arranged in the band width direction are formed in a plurality of pairs arranged in the band length direction. The pair of through holes 331C are provided so that the band-shaped magnetic material 31 is located between them.

As shown in FIG. 4, the second adhesive layer 332 is provided between the second insulating layer 331 and the band-shaped magnetic material 31 or the first flexible substrate 32, and adheres to each other. As shown in FIG. 7, the second conductive pattern 333 is formed by etching a copper foil on the surface of the second insulating layer 331 on the side away from the band-shaped magnetic material 31. The second conductive pattern 333 is formed in a line shape connecting between one side of the pair of through holes 331C in the band width direction and the other side of the pair of through holes 331C provided adjacent to each other in the band width direction. There is. In the second conductive pattern 323, by connecting a plurality of pairs of through holes 321C to each other, a plurality of lines slightly inclined with respect to the band width direction are formed side by side in the band length direction.

The fourth insulating layer 334 is provided in the same size and shape as the second insulating layer 331, and is provided so as to sandwich and cover the second conductive pattern 333 with the second insulating layer 331. The fourth adhesive layer 335 adheres between the second insulating layer 331 and the fourth insulating layer 334.

The filling conduction portion 34 is formed by filling the through holes 321C and 331C of the first and second insulating layers 321 and 331, for example, by applying copper plating. The filling conductive portion 34 connects one end of a line along the band width direction of the first conductive pattern 323 to one end of a slightly inclined line of the second conductive pattern 323. The first and second conductive patterns 323 and 333 and the filled conductive portion 34 are winding-shaped exciting coils 35 around which the band-shaped magnetic body 31 is wound.

Further, in the present embodiment, as shown in FIG. 3, the above-mentioned band-shaped magnetic material 31, the covering portions 321A and 331A covering both surfaces thereof, and the portions overlapped with the covering portions 321A and 331A are designated as the sensor main body portion 37. The electrode forming portions 321B and 331B and the portions overlapped with these electrode forming portions 321B and 331B are referred to as connection portions 38.

By pressing the above-mentioned magnetic sensor 3 in a high temperature (100 ° C. to 200 ° C.) environment, the first to fourth adhesive layers 322, 332, 325, and 335 are in close contact with the upper and lower layers in a melted state. After that, by returning to room temperature, the first to fourth adhesive layers 322, 332, 325, and 335 are solidified and maintain a close contact state. The first to fourth adhesive layers 322, 332, 325, and 335 are hardened, but the band-shaped magnetic material 31 and the first and second flexible substrates 32 and 33 can be flexibly deformed.

Next, the reinforcing body 4A for reinforcing the magnetic sensor 3 will be described with reference to FIGS. 8 to 11. The magnetic sensor 3 shown in FIGS. 8 to 11 omits the connection portion 38 for the sake of simplicity.

The reinforcing body 4A is made of a strip-shaped non-magnetic material (for example, plastic), and both ends thereof are overlapped and contacted in the thickness direction to form an annular shape. The reinforcing body 4A is composed of a first reinforcing member 4A1 and a second reinforcing member 4A2, which are made of separate parts. The first reinforcing member 4A1 and the second reinforcing member 4A2 are each formed in a substantially U shape along a semicircle. Hinge portions 4A3 are provided at one ends T11 and T21 of the first reinforcing member 4A1 and the second reinforcing member 4A2.

As shown in FIG. 11, the hinge portion 4A3 includes a shaft portion 4A31 provided at one end portion T21 of the second reinforcing member 4A2 and a bearing portion 4A32 provided at one end portion T11 of the first reinforcing member 4A1. Has been done. The shaft portion 4A31 is provided in a substantially columnar shape, and is provided so as to project from the end surface of one end portion T21 of the second reinforcing member 4A2 so that its axial direction is along the width direction. The bearing portion 4A32 is formed in a concave shape on the end surface of one end portion T11 of the first reinforcing member 4A1, and the shaft portion 4A31 is inserted. As a result, the first reinforcing member 4A1 and the second reinforcing member 4A2 are rotatable around the bearing portion 4A32, and the other end portions T12 and T22 are freely connectable and detachable around the center of the annular shape.

The other ends T12 and T22 of the first reinforcing member 4A1 and the second reinforcing member 4A2 correspond to both ends of the reinforcing body 4A, and when they are brought close to each other, they are overlapped in the thickness direction as shown in FIG. In the present embodiment, the inner surface of the other end portion T22 of the second reinforcing member 4A2 is overlapped on the outer surface of the other end portion T12 of the first reinforcing member 4A1. Hereinafter, the state in which the other ends T12 and T22 of the first reinforcing member 4A1 and the second reinforcing member 4A2 are overlapped in the thickness direction is referred to as "clamp" or "closed", and the first reinforcing member 4A1 and the second reinforcing member are referred to as "closed". The state in which the other ends T12 and T22 of 4A2 are separated is referred to as "non-clamp" or "open".

The second reinforcing member 4A2 is provided with a step portion 4A4 in the middle thereof. The other end T22 side of the second reinforcing member 4A2 with respect to the step portion 4A4 is provided so as to project outward from the one end portion T21 of the first reinforcing member 4A1 and the second reinforcing member 4A2 with respect to the step portion T21. Has been done. That is, the first reinforcing member 4A1 and the one end portion T21 side of the stepped portion 4A4 of the second reinforcing member 4A2 are provided along a circle having the same diameter. On the other hand, the other end T22 side of the step portion 4A4 of the second reinforcing member 4A2 is along a circle having a diameter larger than that of the step portion 4A4 of the first reinforcing member 4A1 and the second reinforcing member 4A2 with respect to the one end portion T21 side. It is provided.

In the present embodiment, the inner surface of the second reinforcing member 4A2 on the other end T22 side of the stepped portion 4A4, the outer surface of the first reinforcing member 4A1 and the outer surface of one end portion T21 side of the stepped portion 4A4 of the second reinforcing member 4A2. , Are provided along a circle of the same diameter. The stepped portion 4A4 is provided with a through hole 4A5 that penetrates along the center of the annular shape. The through hole 4A5 is provided in a long rectangular shape along the width direction of the reinforcing body 4A.

The sensor main body 37 (hereinafter, simply referred to as the magnetic sensor 3) of the magnetic sensor 3 described above is provided between both ends of the reinforcing body 4A. The magnetic sensor 3 passes through the through hole 4A5 on the inner surface of the second reinforcing member 4A2 on the other end T22 side of the step 4A4, and the second reinforcing member 4A2 and the first reinforcement on the one end T21 side of the step 4A4. It is provided so as to crawl or be attached on the outer surface of the member 4A1.

More specifically, the magnetic sensor 3 is passed through the through hole 4A5, one end portion T31 thereof is provided on the outer surface of the other end portion T12 of the first reinforcing member 4A1, and the other end portion T32 is the other of the second reinforcing member 4A2. It is provided on the inner surface of the end portion T22. As a result, as shown in FIG. 9, when both ends of the reinforcing body 4A (that is, the other ends T12 and T22 of the first reinforcing member 4A1 and the second reinforcing member 4A2) are overlapped, the first to fourth insulating layers are overlapped. Both ends of the band-shaped magnetic material 31 exposed from 321 331, 324, and 334 are also overlapped in the thickness direction and come into contact with each other.

Next, the inner magnetic body 5 and the outer magnetic body 6 will be described with reference to FIG. As shown in FIG. 12, the inner concentrator 5 is composed of a first inner concentrator 51 as a first concentrator divided into two and a second inner concentrator 52 as a second concentrator. The first inner porcelain collector 51 and the second inner porcelain collector 52 are provided in a strip shape, and both ends in the longitudinal direction are formed in a U shape so as to face each other in the thickness direction. The inner concentrator 5 is formed in an annular shape in which both ends of the first inner concentrator 51 and the second inner concentrator 52 are in contact with each other.

The outer concentrator 6 is composed of a first outer concentrator 61 as a first concentrator divided into two and a second outer concentrator 62 as a second concentrator. The first outer porcelain collector 61 and the second outer porcelain 62 are provided in a strip shape, and are formed in a U shape so that both ends in the longitudinal direction face each other. The outer concentrator 6 is formed in a circular ring shape in which both ends of the first outer concentrator 61 and the second outer concentrator 62 are in contact with each other.

The other ends T12 and T22 of the first reinforcing member 4A1 and the second reinforcing member 4A2 described above, the first inner collector 51, both ends of the second inner collector 52, the first outer collector 61, and the second outer side. Both ends of the magnetic collector 62 may be formed in a straight line (flat plate shape) instead of being formed in an arc shape.

Further, the above-mentioned first reinforcing member 4A1, the magnetic sensor 3 on the first reinforcing member 4A1, the first inner magnetic collector 51 and the first outer magnetic collector 61 constitute the left core portion 20L, and the second reinforcing member 4A2 and the first. 2 The magnetic sensor 3, the second inner porcelain collector 52, and the second outer porcelain collector 62 on the reinforcing member 4A2 constitute the right core portion 20R.

According to the above configuration, as shown in FIGS. 10 and 12, the first reinforcing member 4A1 and the second reinforcing member 4A1 centering on the shaft portion 4A31 are separated from each other so as to separate both ends of the reinforcing body 4A in the thickness direction. Rotate 4A2. As a result, both ends of the reinforcing body 4A and both ends of the strip-shaped magnetic body 31 provided on the reinforcing body 4A are separated from each other, resulting in a non-clamping state. At this time, as shown in FIG. 12, both ends of the first inner collector 51 and the second inner collector 52, the first outer collector 61 and the second outer collector 62 allow the movement of the reinforcing body 4A. Both ends are separated from each other. After that, after passing the object 8 to be measured through the gap between both ends of the distant reinforcing body 4A, the first reinforcing member 4A1 and the second reinforcing member 4A2 centering on the shaft portion 4A31 so as to bring both ends of the reinforcing body 4A closer to each other. As shown in FIGS. 8 and 9, both ends of the reinforcing body 4A and both ends of the band-shaped magnetic body 31 are overlapped in the thickness direction, and a clamped state is obtained.

At this time, as shown in FIG. 1, both ends of the first inner porcelain collector 51 and the second inner porcelain 52, the first outer porcelain 61 and the second outer porcelain 62 are also brought close to each other.

According to the first embodiment described above, both ends of the band-shaped magnetic body 31 are overlapped and in contact with each other in the thickness direction. As a result, a sufficient contact area can be maintained for the opening / closing operation of the band-shaped magnetic body 31, so that the thin band-shaped magnetic body 31 can be adopted as the clamp-type excitation core. Further, since the band-shaped magnetic body 31 has only one contact point, it is sufficient to make good contact at only one point, and the sensor performance can be easily maintained.

Further, according to the first embodiment, the excitation coil 35 is composed of the first and second conductive patterns 323 and 333 provided on the first and second flexible substrates 31 and 32, and the filling conductive portion 34. .. This eliminates the need for winding the winding as compared with the case where the winding is wound around the band-shaped magnetic body 31 to form the exciting coil 35. Moreover, since the shape of the exciting coil 35 is stable, the magnetic sensor 3 can be made with little variation in the exciting characteristics. Further, by forming the magnetic sensor 3 with the first and second flexible substrates 31 and 32, the thickness direction can be made very thin (for example, 1 mm or less), so that the overall size of the current sensor 1 can be reduced. can.

Further, according to the first embodiment, since the band-shaped magnetic material 31 is sandwiched between the first and second flexible substrates 32 and 33, the first and second flexible substrates 32 and 33 increase the strength of the band-shaped magnetic material 31. be able to. Further, by devising the shapes of the first and second flexible substrates 32 and 33, the degree of freedom of fixing the band-shaped magnetic body 31 to the reinforcing body 4A and the inner and outer magnetic collecting bodies 5 and 6 is increased.

Further, according to the first embodiment, the first insulating layer 321 and the third insulating layer 324 are provided so as to cover one end of the band-shaped magnetic material 31 in the band length direction and expose the other end. The second insulating layer 331 and the fourth insulating layer 334 are provided so as to cover the other end of the band-shaped magnetic body 31 in the band-length direction and expose one end, and the band-shaped magnetic body 31 is provided. The portions exposed from the first to fourth insulating layers 321, 331, 324, and 335 are in contact with each other and overlapped. As a result, both ends of the band-shaped magnetic material 31 can be easily overlapped.

Further, according to the first embodiment, the first and second insulating layers 321 and 324 are provided with electrode forming portions 321B and 331B protruding in the band width direction of the band-shaped magnetic body 31, and the tip of the electrode forming portion 321B is provided. Is provided with a pair of electrodes 36, and the first conductive pattern 323 is provided so as to connect both ends of the exciting coil 35 and the pair of electrodes 36, respectively. As a result, both ends of the excitation coil 35 can be easily connected to the excitation circuit 11 and the detection circuit 12.

Further, according to the first embodiment, the magnetic sensor 3 includes third and fourth insulating layers 324 and 335 that cover the first and second conductive patterns 323 and 333. Thereby, the first and second conductive patterns 323 and 333 can be insulated.

Further, according to the first embodiment, the sensor head 2 is made of a non-magnetic material, and further includes a reinforcing body 4A formed in an annular shape by overlapping and contacting both ends in the thickness direction, and the reinforcing body 4A is provided with the reinforcing body 4A. Both ends are detachably provided, and the magnetic sensor 3 is provided on the reinforcing body 4A. As a result, even the flexible magnetic sensor 3 can maintain its shape, so that the mechanical strength can be increased without affecting the characteristics of the band-shaped magnetic body 31.

Further, according to the first embodiment, the magnetic sensor 3 is passed through the through hole 4A5, and one end portion T31 thereof is placed on the outer surface of the other end portion T12 (= one end portion of the reinforcing body 4A) of the first reinforcing member 4A1. The other end T32 is provided on the inner surface of the other end T22 (= the other end of the reinforcing body 4A) of the second reinforcing member 4A2. Thereby, the magnetic sensor 3 can be easily supported so that both ends of the band-shaped magnetic body 31 overlap in the thickness direction only by providing the through hole 4A5 in the reinforcing body 4A.

Further, according to the first embodiment, the reinforcing body 4A is provided with a step portion 4A4. Further, the other end portion T22 side of the second reinforcing member 4A2 with respect to the stepped portion 4A4 protrudes to the outside of the annular shape with respect to the one end portion T21 side of the first reinforcing member 4A1 and the second reinforcing member 4A2 with respect to the stepped portion 4A4. It is provided in. Further, a through hole 4A5 is formed in the step portion 4A4. As a result, it is possible to prevent the magnetic sensor 3 from being deformed even if it is passed through the through hole 4A5, and it is possible to improve the characteristics of the band-shaped magnetic body 31.

Further, the inner surface of the second reinforcing member 4A2 on the other end T22 side of the stepped portion 4A4, the outer surface of the first reinforcing member 4A1 and the outer surface of the second reinforcing member 4A2 on the one end portion T21 side of the stepped portion 4A4 are the same. It is provided along a circle of diameter. As a result, the shape of the band-shaped magnetic material 31 can be kept circular even through the through hole 4A5.

Further, according to the first embodiment, the reinforcing body 4A is composed of a first reinforcing member 4A1 and a second reinforcing member 4A2 composed of different parts, and one end portion of the first reinforcing member 4A1 and the second reinforcing member 4A2. Hinge portions 4A3 are provided on T11 and T21 and are swingably attached around the shaft portion 4A31, and the other ends T12 and T22 of the first reinforcing member 4A1 and the second reinforcing member 4A2 are formed in the thickness direction. It is piled up. This makes it possible to hold the band-shaped magnetic material 31 with a simple structure and open / close both ends thereof.

By the way, in the above-described first embodiment, as shown in FIGS. 13 and 14, two points on the outer surface of the first reinforcing member 4A1 and the second reinforcing member 4A2 sandwiching the shaft portion 4A31 are designated as A and B, and the inside thereof. Let A'and B'are the two points on the side surface. Then, the distance between the two points A and B at the time of clamping is LCAB, the distance between the two points A'and B'is LCA'B'(see FIG. 13), and the distance between the two points A and B at the time of non-clamping is set. Is LOAB, and the distance between the two points A'and B'is LOA'B'. The following inequalities (1) and (2) hold for these distances.
LCAB> LOAB ... (1)
LCA'B'<LOA'B'... (2)

That is, the above equations (1) and (2) are established by providing the band-shaped magnetic body 31 on the outer surface of the hinge portion 4A3 and providing the shaft portion 4A31 between the inner surface and the outer surface of the reinforcing body 4A. As a result, as shown in FIG. 16, when the band-shaped magnetic body 31 is not clamped, a deformation (deflection) D that does not follow the reinforcing body 4A occurs. However, as shown in FIG. 15, at the time of clamping, the band-shaped magnetic body 31 is arranged along the reinforcing body 4A, and deformation (deflection) D does not occur. As a result, the shape of the band-shaped magnetic material 31 can be made symmetrical at the time of clamping. Therefore, the position of the object to be measured 8 is displaced from the center of the band-shaped magnetic body 31, and the influence of an external magnetic field is increased, so that the sensor performance can be improved. In addition, in FIGS. 13 to 16 described above and FIGS. 17 to 22 described below, the step portion 4A4 is omitted for the sake of simplicity.

Further, according to the above-described embodiment, the reinforcing body 4A is provided with the stepped portion 4A4, but the present invention is not limited to this. The step portion 4A4 is not essential, and the reinforcing body 4A may be provided with a through hole 4A5 along the radial direction.

Further, according to the above-described embodiment, the strip-shaped magnetic material 31 is provided on the outer surface of the hinge portion 4A3, but as shown in FIGS. 17 and 18, the strip-shaped magnetic material 31 is provided on the inner surface of the hinge portion 4A3. It may be provided. In this case, the through hole 4A5 is provided in the first reinforcing member 4A1.

Further, according to the above-described embodiment, the shaft portion 4A31 is provided between the inner surface and the outer surface of the reinforcing body 4A, but the present invention is not limited to this. As shown in FIGS. 19 and 20, the shaft portion 4A31 may be provided outside the outer surface of the reinforcing body 4A.

Further, as shown in FIGS. 21 and 22, the shaft portion 4A31 may be provided inside the inner surface of the reinforcing body 4A. In this case, the following inequalities (3) and (4) hold for the distances LCAB, LCA'B', LOAB, and LOA'B'.
LCAB> LOAB ... (3)
LCA'B'>LOA'B'... (4)

In this case, regardless of whether the strip-shaped magnetic body 31 is provided on the outer surface or the inner surface of one end portions T11 and T21 of the first reinforcing member 4A1 and the second reinforcing member 4A2, deformation D occurs during non-clamping and deformation occurs during clamping. D does not occur.

Further, in the above-described first embodiment, the reinforcing body 4A is composed of the first reinforcing member 4A1 and the second reinforcing member 4A2 of the two members, and both ends of the reinforcing body 4A are provided in a detachable manner by the hinge portion 4A3. However, it is not limited to this. If the reinforcing body 4A is provided with a material having a certain degree of elasticity, both ends of the reinforcing body 4A can be made detachable without the hinge portion 4A3. Further, if a part of the reinforcing body 4A is thinned to be deformable, both ends of the reinforcing body 4A can be made connectable and detachable without the hinge portion 4A3.

Further, in the above-described first embodiment, an example in which the magnetic sensor 3 is used has been described, but the present invention is not limited to this. A plurality of magnetic sensors 3 may be arranged in the band width direction, and the object to be measured 8 may be passed through the center of the plurality of magnetic sensors 3. In this case, the detection circuit 12 adds the exciting voltage or exciting current of the exciting coil 35 of each magnetic sensor 3 and passes it through the LPF circuit 13.

(Second Embodiment)
Next, the non-contact type current sensor 1 in the second embodiment will be described with reference to FIG. 23. The difference between the first embodiment and the second embodiment is the configuration of the reinforcing body 4B. Since the parts other than the reinforcing body 4B are the same as those in the first embodiment, detailed description thereof will be omitted here.

In the first embodiment, the reinforcing body 4A is provided with the through hole 4A5, but the reinforcing body 4B shown in FIG. 23 is not provided with the through hole 4A5.

The reinforcing body 4B is composed of a U-shaped first inner reinforcing member 4B1 and a first outer reinforcing member 4B2 made of a magnetic material (for example, plastic), a second inner reinforcing member 4B3, and a second outer reinforcing member 4B4. .. Each of these reinforcing members 3C11 to 3C14 is formed in a substantially U shape along a semicircle. Hinge portions 4B5 are provided at one ends T11 and T21 of the first inner reinforcing member 4B1 and the second inner reinforcing member 4B3. Since the hinge portion 4B5 is the same as the hinge portion 4A3 of the first embodiment, detailed description thereof will be omitted here.

The magnetic sensor 3 is provided on the outer surface of the first inner reinforcing member 4B1 and the second inner reinforcing member 4B3. The first outer reinforcing member 4B2 sandwiches and holds the magnetic sensor 3 with the first inner reinforcing member 4B1. The other end T12 of the first outer reinforcing member 4B2 is provided on the one end T11 side of the other end T12 of the first inner reinforcing member 4B1. As a result, the outer surface of the strip-shaped magnetic body 3C2 provided at the other end T12 of the first inner reinforcing member 4B1 is exposed.

The second outer reinforcing member 4B4 holds the magnetic sensor 3 sandwiched between the second outer reinforcing member 4B4 and the second inner reinforcing member 4B3. The other end T22 of the second outer reinforcing member 4B4 is provided on the one end T21 side of the other end T22 of the second inner reinforcing member 4B3. As a result, the inner surface of the magnetic sensor 3 provided at the other end T22 of the second outer reinforcing member 4B4 is exposed.

According to the above configuration, the reinforcing members 3C11 to 3C14 rotate around the hinge portion 4B5 even if the through hole is not provided, and both ends of the band-shaped magnetic body 31 provided by the magnetic sensor 3 are brought close to each other in the thickness direction. It can be stacked on top of each other, or both ends of the band-shaped magnetic material 31 can be separated from each other.

(Third Embodiment)
Next, the non-contact type current sensor in the third embodiment will be described with reference to FIGS. 24 and 25. The difference between the first embodiment and the third embodiment is the configuration of the magnetic sensor 3. Since the parts other than the magnetic sensor 3 are the same as those in the first embodiment, detailed description thereof will be omitted here.

In the first embodiment, the first and second insulating layers 321 and 331 are formed in a substantially T shape, and the electrodes 36 are provided on the electrode forming portions 321B and 331B protruding in the band width direction. In the third embodiment, the pair of electrodes 36 of the excitation coil 35 are provided on the thin band-shaped electrode forming substrate 39 having the same size and shape as the first and second flexible substrates 32 and 33.

The electrode forming substrate 39 includes a fifth insulating layer 391, a conductive pattern 392, a sixth insulating layer 393, a fifth adhesive layer 394, and an electrode 36. The fifth insulating layer 391 is provided in a thin band shape having the same size and shape as the first and second flexible substrates 32 and 33, and is made of a well-known insulating member such as polyimide.

A pair of electrodes 36 are formed by electroless gold plating on the other side of the fifth insulating layer 391 in the band length direction.

The conductive pattern 392 is formed by etching a copper foil on the fifth insulating layer 391. As shown in FIG. 25, the conductive pattern 392 includes a pair of connecting portions 392A provided on one side in the band length direction and a line-shaped connecting portion 392B connecting the pair of connecting portions 392A and the pair of electrodes 36, respectively. Have. The pair of connecting portions 392A are provided to connect to the portions corresponding to both ends of the exciting coil 35 of the first conductive pattern 323 provided on the first flexible substrate 32.

The sixth insulating layer 393 is provided so as to sandwich and cover the conductive pattern 392 with the fifth insulating layer 391. The sixth insulating layer 393 has a slightly shorter band length than the fifth insulating layer 391, and the connecting portion 392A is exposed. Further, the sixth insulating layer 393 is formed with exposed holes (not shown) that expose the pair of electrodes 36.

Further, one end of the first flexible substrate 32 in the band length direction is not covered with the third insulating layer 324, and a portion corresponding to both ends of the exciting coil 35 of the first conductive pattern 323 is partially exposed. Therefore, the portion where the first conductive pattern 323 of the first flexible substrate 32 is exposed and the portion where the pair of connecting portions 392A of the electrode forming substrate 39 are exposed are overlapped with each other by the fifth adhesive layer 394. When bonded, the first conductive pattern 323 is connected to the pair of connecting portions 392A. The electrode forming substrate 39 is not adhered to the first flexible substrate 32 except for the portion where the sixth insulating layer 393 is absent. Therefore, the other side of the electrode forming substrate 39 in the band length direction can be turned inside out and connected to the electrode 36.

The present invention is not limited to the above embodiment. That is, it can be variously modified and carried out within a range that does not deviate from the gist of the present invention.

2 Sensor head 3 Magnetic sensor 4A Reinforcing body 4B Reinforcing body 5 Inner magnetic collecting body (magnetic collecting body)
6 Outer magnetic collector (collector)
7 Feedback coil 10 Current detection circuit (current detection means)
31 Band-shaped magnetic material 34 Filled conductive part 36 Electrode 51 First inner porcelain collector (first porcelain collector)
52 2nd inner porcelain (1st porcelain)
61 1st outer concentrator (2nd concentrator)
62 Second outer porcelain (second porcelain)
321 First insulating layer 321B Electrode forming part (protruding part)
321C Through hole 324 Third insulating layer 323 First conductive pattern 331 Second insulating layer 331B Electrode forming part (protruding part)
331C through hole 333 2nd conductive pattern 334 4th insulating layer

Claims (6)

On the first and second insulating layers, the band-shaped magnetic material formed in an annular shape by overlapping both ends in the thickness direction and contacting each other, the first and second insulating layers covering both sides of the band-shaped magnetic material, respectively. Each of the first and second conductive patterns provided in the above, and a filled conductive portion filled in the through holes penetrating the first and second insulating layers and connecting between the first and second conductive patterns. With a magnetic sensor
It is made of a non-magnetic material and is provided with a reinforcing body formed in an annular shape by overlapping both ends in the thickness direction and contacting each other.
The first and second conductive patterns and the filled conductive portion are provided so as to form a winding around the strip-shaped magnetic material.
Both ends of the reinforcing body are provided so as to be removable from each other.
The magnetic sensor is provided on the reinforcing body, and the magnetic sensor is provided on the reinforcing body .
A through hole is formed in the reinforcing body, and a through hole is formed.
The magnetic sensor is passed through a through hole formed in the reinforcing body, and one end thereof is provided on the outer surface of one end portion of the reinforcing body and the other end portion is provided on the inner surface of the other end portion of the reinforcing body. A sensor head characterized by being magnetized. The first insulating layer is provided so as to cover one end of the band-shaped magnetic material in the band length direction and expose the other end.
The second insulating layer is provided so as to cover the other end of the band-shaped magnetic material in the band length direction and expose one end.
The sensor head according to claim 1, wherein the strip-shaped magnetic material is such that portions exposed from the first and second insulating layers are in contact with each other and overlapped with each other. The first and second insulating layers are provided with protrusions protruding in the band width direction of the band-shaped magnetic material.
A pair of electrodes is provided at the tip of the protrusion.
The sensor head according to claim 1 or 2, wherein any one of the first and second conductive patterns is provided so as to connect both ends of the winding and the pair of electrodes, respectively. The sensor head according to any one of claims 1 to 3, further comprising a third and fourth insulating layers that cover the first and second conductive patterns, respectively. It is composed of a band-shaped first inner magnetic body and a second inner magnetic body, and both ends of the first inner magnetic body and the second inner magnetic body are in contact with each other to form an annular shape, which is arranged inside the reinforcing body. With the inner magnetic material
It is composed of a band-shaped first outer magnetic body and a second outer magnetic body, and both ends of the first outer magnetic body and the second outer magnetic body are in contact with each other to form an annular shape, which is arranged outside the reinforcing body. With the outer magnetic material
With a feedback coil ,
The magnetic sensor and the reinforcing body are sandwiched between the inner magnetic body and the outer magnetic body, and the magnetic sensor and the reinforcing body are sandwiched between the inner magnetic body and the outer magnetic body.
The inner magnetic material, the outer magnetic material, and the magnetic sensor constitute an annular core.
The sensor head according to any one of claims 1 to 4 , wherein the feedback coil is wound entirely along the circumferential direction of the core . The sensor head according to claim 5 and
A current sensor comprising: a current detecting means for detecting a current flowing through an object to be measured penetrated through the band-shaped magnetic material.

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