JPH05341025A - Magnetic field sensing device - Google Patents

Abstract

PURPOSE:To sense the magnetic field of a vital organism such as human brain or heart precisely using a compact configuration. CONSTITUTION:In a fixed position a bed 2 is installed with capability of elevating and sinking, and a gate-form frame 6 straddling this bed as if it was a gate is provided movably in the longitudinal direction of the bed 2. In the over- part of the bed, a magnetic field sensing means 8 is furnished which is movable in the vertical direction to the bed longitudinal and consists, for example, of a super-conductive quantum interferential fluxmeter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting a weak magnetic field generated by a living body such as human brain and heart.

[0002]

2. Description of the Related Art In such a magnetic field detection device for a human body, a relatively compact device for detecting a magnetic field over a wide range of the human body has not been realized.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic field detection device for a human body, which has a small structure and is capable of accurately detecting a weak magnetic field generated from a living body. is there.

[0004]

According to the present invention, there is provided a bed provided at a fixed position, a gate-shaped frame which straddles the bed in a gate shape and is movable in the longitudinal direction of the bed, and an upper portion of the frame. A magnetic field detection device that is movable above the bed in a direction perpendicular to the longitudinal direction of the bed and that includes magnetic field detection means for detecting a weak magnetic field of a human body on the bed.

The present invention also relates to a threaded rod having a threaded portion extending along the longitudinal direction of the bed, rotatable about its longitudinal axis, and having screw portions having mutually opposite screw directions along the longitudinal direction. , A pair of first and second nuts that are screwed to each threaded portion, a first link whose both ends are pin-connected to the lower portion of the first nut and the bed, and both ends of the first nut and the fixed position. A pin is coupled to the second link having the same length as the first link; a third link having both ends pin coupled to the second nut and the lower part of the bed; and a second nut and a fixed position. Both ends are pin-coupled, and include a fourth link having a third link and a third link having the same length, and a lifting means for lifting the bed in a horizontal state.

[0006]

According to the present invention, a bed capable of supporting a human body in a lying state is provided at a fixed position, and a magnetic field detecting means is provided on a portal frame straddling the bed in a portal shape. , Is movable in the longitudinal direction of the bed, and the magnetic field detecting means is movable in the direction perpendicular to the longitudinal direction of the bed at the upper part of the frame, thus detecting the magnetic field of a wide range of detected sites such as the brain and the heart of the human body. You will be able to do it. Since the bed is provided at a fixed position and is not configured to move, the occurrence of measurement error due to vibration can be suppressed.
Further, since the gate-shaped frame straddling the bed is configured to move and the bed does not move as described above, the entire configuration can be downsized.

Further, according to the present invention, the screw rod, the first and second nuts, and the first to fourth links are combined so that the magnetic field detecting means can easily detect the magnetic field by moving up and down the bed. The bed is configured so that it can be moved up and down while keeping the bed horizontal. Such a structure can be realized by a synthetic resin such as engineering plastic or fiber reinforced plastic (abbreviated as FRP). By using such a material, a weak magnetic field of a living body can be detected with high accuracy. Therefore, it becomes possible to detect a magnetic field in the order of several tens of fT.

[0008]

FIG. 1 is a simplified perspective view of an embodiment of the present invention. A person 1 whose magnetic field of a living body such as a brain and a heart is to be detected is supported with at least the upper half of the body lying on a horizontal support portion 3 of a bed 2 provided at a fixed position, and a foot 4 of the bed 2. It is supported by a foot support member 5 provided at one end in the longitudinal direction, thus making the bed 2 as short as possible. The gate-shaped frame 6 that straddles the bed in a gate shape is provided on the floor in the magnetically shielded room so as to be movable in the longitudinal direction of the bed 2 in the arrow 7 and the opposite direction. A magnetic field detecting means 8 is provided above the frame 6, and the magnetic field detecting means 8 is movable above the bed 2 in a direction 9 perpendicular to the longitudinal direction of the bed 2 and the opposite direction.
By this magnetic field detecting means 8, the brain of the person 1 on the bed 2,
It detects and measures the weak magnetic fields generated by living bodies such as the heart, arms, and eyes.

FIG. 2 is a side view of the magnetic field detecting device shown in FIG. 1, FIG. 3 is a plan view of the magnetic field detecting device, and FIG. 4 is a right side view of the magnetic field detecting device in FIGS. It is the front view seen. With reference to these drawings, the bed 2 is raised in the direction of arrow 11 or lowered in the opposite direction by the elevating means 10 provided below the bed 2, whereby the distance between the bed 2 and the magnetic field detecting means 8 is adjusted. Therefore, accurate detection of the magnetic field is possible.

The gate-shaped frame 6 includes leg portions 11 and 12 arranged on both sides of the bed 2 and a connecting portion 13 that connects the upper portions of the leg portions 11 and 12 and extends horizontally across the bed 2. And has a gate shape as described above and is formed in an inverted U shape. The connecting portion 13 is provided with a pair of linear bearings 14 extending parallel to the direction of the arrow 9, whereby the moving carriage 15 to which the magnetic field detecting means 8 is attached moves in the direction of the arrow 9 and the opposite direction. You are free. The connecting portion 13 is formed with an elongated insertion hole 16 along the arrow 9, and the insertion portion 16 has a detecting portion 17 of the magnetic field detecting means 8.
Is provided so as to project downward. Connecting the moving carriage 15 to the connecting portion 1
A stopper 17 is provided to lock it in the desired position on 3 and prevent movement in the direction of arrow 9 and vice versa. The stopper 17 includes a bolt that is screwed into a screw hole that extends in the vertical direction (vertical direction in FIG. 2, vertical direction to the paper surface in FIG. 3) on the moving carriage 15, and a disk-shaped knob fixed to the upper end portion of the bolt. By rotating the knob 18, the lower end of the bolt abuts the upper surface of the connecting portion 13, thus preventing movement of the moving carriage 15 in the direction of arrow 9 and vice versa.

A screw rod 20 is attached to the connecting portion 13 by a bracket 19 in order to allow the carriage 15 to move in the arrow 9 direction and its opposite direction in a state where the stop state of the movement carriage 15 by the stopper 17 is released. It is rotatably provided about a horizontal axis, and the axis of the screw rod 20 extends parallel to the axis of the linear bearing 14. The threaded rod 20 can be rotationally driven by a handle 21 provided on one side of one leg 11. A nut 22 is attached to the screw rod 20.
Are screwed together, and the nut 22 is fixed to the moving carriage 15. By rotating the handle 21 in this manner, the screw rod 20 is rotationally driven, whereby the nut 22 screwed to the screw rod 20, and thus the movable carriage 15 is driven.
Can be displaced in the direction of arrow 9 and vice versa. A peep hole 23 is formed in the leg portion 11, and the measuring state of the detected portion of the person 1 can be observed from the side by the detecting portion 17 of the magnetic field detecting means 8.

The floor is provided with linear bearings 24 parallel to both sides of the bed 2.
The legs 11, 12 and thus the frame 6 are movable along it in the direction of the arrow 7 and vice versa. Leg 11
By operating the stopper 25 provided at the side portion of the frame 2, the movement of the frame 6 along the longitudinal direction of the bed 2 can be blocked and stopped. The other leg 12 is also provided with a peephole 23 and a stopper 25.

FIG. 5 is a simplified plan view of the elevating means 10, FIG. 6 is a side view of the elevating means 10, and FIG. 7 is a side view of a part of the elevating means 10. With reference to these drawings, the bed 2 is vertically guided and displaceable by vibration damping means 26 provided at its four corners, and its vibration is prevented. The vibration isolator 26 has a vertical axis below the bed 2 and extends downward in the guide tube 2.
7 and a support rod 28 fitted and inserted in the guide cylinder 27, and the support rod 28 is vertically fixed to the floor. Anti-vibration means 2
The element 6 prevents minute vibrations from the floor to the bed 2 by the action of the flow resistance of air pressure or oil.

The elevating means 10 has two sets of elevating mechanisms 29 and 30 along the longitudinal direction of the bed 2. One elevating mechanism 29 and the other elevating mechanism 30 have a similar configuration, and the elevating mechanism 30 is shown by adding the subscript a to the reference numeral of the corresponding component of the elevating mechanism 29. Lifting mechanism 2
In FIG. 9, the screw rod 31 has a horizontal axis line, extends along the longitudinal direction of the bed 2, is rotatable about the longitudinal axis line, and is rotationally driven by the handle 32. This threaded rod 31 has threaded portions 33, 34, which have mutually opposite threading directions along its length. Each threaded portion 33, 34 has a pair of a first nut 35 and a second nut 35.
The nut 36 is screwed together. Both ends of the first link 38 are pin-coupled to the first nut 35 and the lower bracket 37 of the bed 2 by pins 39 and 40. The first nut 35 and the bracket 41 provided at the fixed position include
Both ends of the second link 42 are pin-coupled by the pins 43 and 44. The second link 42 has the same length as the first link 38, in other words, the distance between the pins 39 and 40 is equal to the distance between the pins 43 and 44.

The third link 45 has pins 46 and 4 at both ends on the second nut 36 and the bracket 37 at the bottom of the bed 2.
Combined by 7. Both ends of the fourth link 48 are coupled to the second nut 36 and the bracket 41 provided at the fixed position by pins 49 and 50. The fourth link 48 has the same length as the third link 45, in other words, the distance between the pins 46 and 47 is equal to the distance between the pins 49 and 50. The screw rod 31 of the one elevating mechanism 29 is connected to the screw rod 31 a of the other elevating mechanism 30 by the shaft joint 51. In this manner, the handle 32 is rotationally operated to rotationally drive the screw rods 31 and 31a around their axes, so that the bed 2 is moved up and down, and thereby, the person 1 on the support portion 3 of the bed 2 and the frame 6 are attached. It is possible to adjust the distance from the detection unit 17 of the magnetic field detection means 8 to measure the magnetic field of the living body of each detected part of the person 1 with high accuracy.

Bed 2, frame 6 and lifting means 10
Is made of non-metal and is made of synthetic resin material such as engineering plastic and fiber reinforced plastic. As a result, the magnetic field detecting means 8 can detect the magnetic field with high accuracy, and the magnetic field detection error can be eliminated or reduced.

The magnetic field detecting means 8 includes, for example, a pickup coil arranged in the detecting section 17, a coupling coil connected to the pickup coil, and a superconducting quantum interference device (abbreviated as SQUID) magnetically coupled to the coupling coil.
And the pickup coil, the coupling coil, and the superconducting quantum interference device are stored in a liquefied gas such as liquid helium. The superconducting quantum interference device has a structure in which one or two Josephson couplings are combined with a superconducting ring.
This superconducting quantum interference device is another
The two coupling coils are electromagnetically coupled and an electric signal corresponding to the magnetic field of the living body is extracted. The magnetic field detecting means 8 may have not only such a structure having such a superconducting quantum interference device, but also other structures.

[0018]

As described above, according to the present invention, the bed is provided at a fixed position, the magnetic field detecting means is provided on the portal frame straddling the bed, and the portal frame is provided so as to be movable in the longitudinal direction of the bed. The magnetic field detecting means is movable in the direction perpendicular to the longitudinal direction of the bed on the upper part of the frame, and in this way, it is possible to detect the weak magnetic field of the detection site over a wide range of the human body. In addition, since the bed is fixed and the gate-shaped frame is moved in such a structure,
For example, the structure can be made smaller than the structure in which the bed is moved. This is particularly important in view of the fact that the present magnetic field detection device is used in a magnetically shielded room so as not to be adversely affected by the earth's magnetism and an external magnetic field. It is possible to reduce the size of such a magnetic shield structure.

Further, since the relatively long bed is provided at a fixed position, a weak magnetic field detection error due to vibration is suppressed to a small level, and a highly accurate magnetic field can be detected.

Further, according to the present invention, the screw rod, the first and second nuts, and the first to fourth links are combined in order to raise and lower the bed while maintaining the horizontal state. By moving the bed up and down, the magnetic field of the living body can be accurately detected by the magnetic field detecting means. Furthermore, such a configuration is realized by a non-metallic material such as a synthetic resin material that does not adversely affect magnetic field detection, and thus a weak magnetic field can be detected with high accuracy.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic field detection device according to an embodiment of the present invention.

FIG. 2 is a side view of the magnetic field detection device of the embodiment shown in FIG.

FIG. 3 is a plan view of the magnetic field detection device shown in FIGS. 1 and 2.

FIG. 4 is a front view of the magnetic field detection device as viewed from the right side of FIGS. 2 and 3.

5 is a simplified plan view of the lifting means 10. FIG.

6 is a side view of the elevating means 10. FIG.

7 is a side view of one lifting mechanism 29 of the lifting means 10. FIG.

[Explanation of symbols]

 1 person 2 beds 6 portal frame 8 magnetic field detecting means 10 elevating means 11, 12 leg section 13 connecting section 14, 24 linear bearing 15 moving carriage 17, 25 stopper 20 screw rod 22 nut 29, 30 elevating mechanism 31 screw rod 33, 34 screw part 35 1st nut 36 2nd nut 37,41 bracket 38 1st link 42 2nd link 45 3rd link 48 4th link

Claims (2)

[Claims] 1. A bed provided at a fixed position, a gate-shaped frame that straddles the bed in a gate shape and is movable in the longitudinal direction of the bed, and a bed provided above the frame and above the bed. And a magnetic field detecting unit that is movable in a direction perpendicular to the direction and that detects a weak magnetic field of a human body on the bed. 2. A threaded rod that extends along the longitudinal direction of the bed, is rotatable about its longitudinal axis, and has a threaded portion having mutually opposite thread directions along the longitudinal direction, and each screw. A pair of first and second nuts screwed to the portion, a first link having both ends pin-coupled to the first nut and the lower portion of the bed, and both ends pinned to the first nut and the fixed position. Combined, first
A second link having the same length as the link, a third link having both ends pin-coupled to the second nut and the lower portion of the bed, and both ends pin-coupled to the second nut and the fixed position. Three
Fourth with a third link having the same length as the link
The magnetic field detection device according to claim 1, further comprising an elevating means including a link and elevating the bed while keeping the bed horizontal.