JPS59148890A - Magnetic coupling circuit for sensor - Google Patents

Abstract

PURPOSE:To reduce the occupation capacity of an input coil without reducing self-inductance by sandwiching a plane output coil between two plane input coils with insulating sheets between. CONSTITUTION:The plane input coils 8 and 10 which are connected to an input probe as a superconductive quantum interferance element inducing a current corresponding to a magnetic signal and wound in the same direction to form self-inductance loops are provided on both sides of the plane output coil 4 with the insulating sheets 7 and 9 between. This constitution reduces the occupation capacity of the input coils without reducing the self-inductance to reduce the size of a magnetic coupling circuit for a sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic coupling circuit for a sensor, and particularly to a reduction in the volume occupied by the magnetic coupling circuit.

Generally, a superconducting quantum interference device (CNG Quanta) is used as a micromagnetic field sensor.
n Interfera, nceDθvice: Hereinafter abbreviated as SQ and UID. ) is available.

Details regarding this can be found in, for example, "Josephson Effect (Basics and Applications)" (published by the Institute of Electrical Engineers of Japan), pages 52 to 8 + "Applications of the Josephson Effect", and will be explained below.

FIG. 1 is a configuration diagram showing the DCSQ and UID Sentsu. In the figure, (I) is the probe coil, (21 is the input coil, (3) is the Josephson effect, and (4) is the primary coil of DC5QUID. The coil (4) includes the Josephson effect (3) at two locations within the coil.Furthermore, the main coil (4) and the input coil (2) of the DC5QtJID are magnetically coupled through a mutual inductance M. Also, globe coil (1) and input coil (2)
is made of superconducting particles and forms a superconducting closed circuit.

The magnetic signal picked up by the probe coil (1) generates a shielding current (1) by the magnetic flux preservation side in the superconducting closed circuit. flows into the input coil (2), and D.

Transmit the change in magnetic flux to the main = 1il (4) of S QU-I D. On the other hand, a constant bias current of an appropriate size is passed to the main coil (4) from DOSQU,
Due to the change in magnetic flux in the main coil (4) from DC8QU.

The potential difference V generated across the main coil (4) of the DCSQ and UID is read out as an output.

This invention is based on the DC! shown as an example above! SQ,UI
This relates to the magnetic coupling circuit part consisting of the input coil and main coil of the D-sensor, and is used in DCSQ, TJIT
) This invention will be explained below using a sensor as an example.

FIG. 2 is a block diagram showing a magnetic coupling circuit of a sensor from a conventional Do 5QTI. In the figure, (4) t is a planar output coil formed on the board, and DC8QTJI
In the D sensor, it is usually called the main coil from DOSQ and U above. This main coil (4) is connected to two Josephson junctions (3) along arrows A and B. (5) is a substrate, T6+, (71 is an insulating sheet.

(2a) and (2b) are planar input coils, which are connected through a hole drilled in the center of an insulating sheet (7) to form one input coil (2).

The input coils (2a) and (2b) form an inductance loop and are magnetically coupled to the main coil (4) from the - side.

The conventional device is configured like this, and the external signal is (
2a) and (2b).
) is transmitted as a change in the internal magnetic flux of the main coil (4).

A constant bias current is passed through the main coil (4),
Knowing the change in the internal magnetic flux of the main coil (4), 1) C,
5 The potential difference generated across the QUID loop is read out as an output. 8 This operation is exactly the same as that of a general T) C6QIT T D.

In order to efficiently transmit external signals to the main coil (4) when performing the above operation, it is necessary to increase the mutual inductance between the main coil (4) and the input coil (2).
There will be a next time. However, the self-inductance of the main coil (4) is desirably as small as possible in order to improve sensitivity. Therefore, in order to increase the mutual inductance, it is necessary to increase the self-inductance of the input coil (2).

Furthermore, from DCSQ, U'f: When used as a magnetic sensor, the input coil (2) constitutes a magnetic flux transmission circuit together with the external globe coil (1), but at this time,
The magnetic flux signal picked up by the probe coil (11) is sent to the input coil (
In order to efficiently transmit data to 2), the globe coil (1
It is necessary to make the self-inductance of the input coil (2) equal to the self-inductance of the input coil (2).

For the two reasons mentioned above, the input coil (2) generally requires a self-inductance of several hundred nanohenries, and in order to achieve this, a long inductance loop is formed on the insulating sheet (7). Must. For this reason, the area occupied by the inductance loop becomes very large, and the DoSQ and UffD sensors become large in size.

This invention was made to eliminate the above-mentioned drawbacks of the conventional coil.

A first planar coil provided on one surface of the planar output coil with an insulating sheet interposed therebetween, and a planar first coil provided on the other surface of the planar output coil with an insulating sheet interposed therebetween and connected to the first coil,
By forming the coil with a planar second coil wound in the same direction, the self-inductance is reduced, and the volume occupied by the inductance loop of the input crab fill is reduced.
The purpose of this invention is to provide a magnetic coupling circuit for sensors that is smaller than 1.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows the D OS CI U according to the present invention:
It is a block diagram which shows one Example of the magnetic coupling circuit for D sensors. In the figure, (8) is a planar first coil provided on the negative side of the output coil (4) with an insulating sheet (7) interposed therebetween.

(9) is an insulating sheet, and (11 is a planar second coil provided on the other side of the output coil (4) via the insulating sheet (9).

The first coil (8) and the output coil (4) are connected through holes drilled in the center and insulating seams (7) and +91, and are wound in the same direction as the first coil (8). These first coil (8) and second coil θ value constitute one input coil (2). The input coil (2) is non-contact.

8 Q IT I Interlinks with the main coil (4) of the D ring, forming inductance loops on both upper and lower sides of the main coil (4). Furthermore, these inductances are loose.

The main coil (4) is formed in such a direction that the magnetic fields generated by the respective loose inductances are strengthened by the position of the main coil (4) at +77 degrees from the DoSQ, U, and are magnetically coupled to the main coil (4).

Note that in the above structure, the number of layers stacked on the substrate (5) is the same as in the conventional structure.

For the DC5QUID sensor configured in this way, the external signal is input to the DC5QUID sensor by the input coil (2).
This is transmitted as a change in the internal magnetic flux of the main coil (4) of the ring. A constant bias current is passed through the main coil (4), and the potential difference generated between both ends of the loop is read out as an output from Dc sQU. This operation is exactly the same as the previous one.

In addition, in the above embodiment, the first coil (sl By and the second coil
The coil body is formed of a single layer, but the first coil (8)
At least one of the second coil 01 and the second coil 01 may have a multilayer structure.

Figure 4 shows the D CS Q, U X I) according to this invention.
FIG. 3 is a partial configuration diagram showing another embodiment of the magnetic coupling circuit for a sensor, in which the second coil αI has a multilayer structure.

In the figure, 01) and +13 are insulating sheets + (I
Da), (10b) and (10c) are the second coils, which are connected through holes drilled in the insulating sheet + Ill, (I) and are wound in the same direction, and this second coil (I Da) , (111b), and (10c), they generate voltage together with the first coil (8), forming an inductance loop in such a direction that the magnetic fields strengthen and trough each other.

In Fig. 4, the second coil (1oa), (1ob), (1
oc) is formed in three layers,
There may be as many layers as necessary.

FIG. 5 is a partial configuration diagram showing another embodiment of the magnetic coupling circuit for DCSQ and UID sensors according to the present invention, in which the first coil (8) has a multilayer structure.

In the figure, 03), 141 is an insulating sheet, (8
a) , (8b) + (8c)t In the first coil, insulating sheet +131. It is connected through the hole drilled in α4 and is wound in the same direction.
), (8b), and (8c), loose inductances are formed in such a direction that the magnetic fields generated together with the second coil α1 are mutually strengthened.

Although FIG. 5 shows a case in which the first coils (8a), (8b), and (8c) are formed in three layers, any number of layers may be used as necessary.

Furthermore, both the first coil (8) and the second coil Ql may have a multilayer structure as shown in FIGS. 4 and 5.

The input coil (2
) Even if it is completely formed, it is effective in reducing the volume occupied by the inductance loop of the input coil (2). It's ox.

Since these are provided on both sides of the output coil (4), there is also the effect of tighter magnetic coupling.

In the above embodiment, the first coil (8) and the second coil (II) were connected at the center of these coils Q and through the center of the output coil (4). ) and the second coil (at the outer periphery of the IQ, and.

The connection may be made outside the output coil (4). (Figure omitted) 1. Figure 6 is a partial configuration diagram showing another embodiment of the magnetic coupling circuit for Do 5QUID sensor according to the present invention.
Together with the first coil (8), the modulating coil is connected to the insulating sheet (7).
) is shown. (11 is a modulation coil, which is provided to feed back the output from p, Do SQ, and U, which modulates the magnetic flux in the main coil (4) of the DC5QUID 17, to the main coil (4). The role is exactly the same as that of general Do 5QUID.Furthermore, the modulation coil (8) is connected to the substrate (
5) Top, insulation sheet +7), '[111, +13.
+13. (It may be provided anywhere in 141, and the new V
A C insulating sheet may be formed, and a modulation coil (19) may be formed thereon.

By the way, in the above example, the globe coil (1) is connected to the input coil (2) and the DCSQ, U, and TD are used as magnetic sensors. It can also be used as a current sensor.

Furthermore, if the current flowing through the resistor is guided to the input coil (2), it can be used as a voltage sensor.

It can also be used as a noise thermometer at low temperatures.

As described above, according to the present invention, the input coil includes a first planar coil provided on one surface of the planar output coil via an insulating sheet, and a second planar coil provided on the other surface of the planar output coil.
Place it through an insulating sheet.

Since the first coil is connected to the second planar coil wound in the same direction, the self-inductance can be lowered, and the input coil can be formed in a narrower volume than before. This is effective in reducing the size of magnetic coupling circuits.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the sensor from Do SQ, U. Figure 2 is a configuration diagram showing the magnetic coupling circuit of the sensor from the conventional DCSQU, and Figure 3 is the 1) C5QU according to the present invention.
1. FIGS. 4, 5, and 6 are block diagrams showing one embodiment of the magnetic coupling circuit for the D sensor.
FIG. 5 is a partial configuration diagram showing another embodiment of a magnetic coupling circuit for a 5QUID sensor. In the figure, (4) is a planar output coil, (71, +
91° (Ill, +1, +131.0 is an insulating sheet, (8) is a planar first coil, 01fd is a planar second coil, (2) is an input coil. Note that the same symbols in the two figures are the same. - or the corresponding part. Agent Kuzu 1!) Trust - Fig. 1 Fig. 2 Fig. 4 Fig. 5 Fig. 6 D Continuation Supplement 11:, sl ((spontaneous) 1988 3 7-.119 Japan f, I゛IS' + Director-General 1.1 (Display of I11 fi? Gansho 521-23
No. 012 No. 2, Name of the invention: Magnetic coupling circuit for sensors; U. To the person making the draw 111 Representative Kata Yuhito Part 5: Column 6 for detailed explanation of the invention in the specification to be amended, Contents of the amendment (1) Details "Occupied volume" on page 2, line 4 and page 9, line 16 will be corrected to "occupied area." (2) [5upper C! on page 2, line 6] ond
uctingQuontanInterference
DeviceJ (-8upper-conduct't
ing Quantnm Interference
Corrected to DeviceJ. (3) Correct "magnetic signal" 1r to "magnetic signal" on page 3, line 3. (41 Correct “bias current” in line 14 of page 4 of the same document to “bias current”. (5) “For increased sensitivity” in line 3 of page 5 of the same document is changed to “for noise reduction.” (6) Correct “Occupied area” in line 9 of page 6 to “occupied area.” (7) Correct “1st coil” in line 20 of page 6 to line 1 of page 1. (8) and the center of the output coil (4) and the insulation sheet (7).
Connect through the hole drilled at 1, +91 to the center of the output coil (4) and the insulation sheath 1- (71, +91).
Connect to the first coil (8) through the hole drilled in the
Correct. 181 "Modulation coil (8)" on page 10, line 13
is corrected to "modulation coil 09". (9) On page 11, line 12, "within one volume" is corrected to "within an area."that's all

Claims (1)

[Scope of Claims] an input coil formed from a second planar coil arranged through the first coil and connected to the first coil and wound in the same direction as the first coil.The input coil and the output coil are A magnetic coupling circuit for a sensor that is magnetically coupled to each other through contact. (2) The first coil and the second coil 9 are connected at the center of these coils and through the center of the output coil. A magnetic coupling circuit for Sentsu according to claim 1. (3) Claim 1, characterized in that at least one of the first coil and the second coil is multilayered.
Or the magnetic coupling circuit for a magnetic sensor according to item 2.