JP6044112B2 - Magnetic force field generator - Google Patents

Description

  The present invention relates to an apparatus for generating a strong magnetic force field, and more particularly to a magnetic force field generator that generates a strong and uniform magnetic force field in a larger space than a conventional magnetic force field generator. .

  Crystallization in a solution in a gravitational field, mixing of liquids, and the like are greatly affected by convection. For example, in the production of crystals, impurities and defects are easily introduced by convection, so that control of convection has been desired. However, on the earth, convection is easily caused by gravity when temperature and density distribution occur in the liquid. When experiments in space became possible, various uses of environments with very low gravity began to take place. In particular, since the determination of protein precise structure is the key to the development of drugs and the like, many space experiments have been conducted to obtain high-quality protein crystals. As a result, the improvement of crystal quality was reported in space experiments, and it was found that the suppression of convection by microgravity has a positive effect on crystallization. However, space experiments have a lot of restrictions on cost, experimental space, experimental period, experimental equipment, access during the experiment, etc., so a simpler method is desirable.

  In order to solve this problem, magnetic force field generators that artificially provide microgravity of the universe on the ground by canceling and suppressing gravity by magnetic force have been proposed (Patent Documents 1 to 3, Non-Patent Documents). 1). Since this magnetic force field generator generates a large magnetic force that counteracts gravity, a ferromagnetic or permanent magnet is placed in a normal superconducting magnet that can only generate a relatively small magnetic force. Creates a large spatial magnetic field change. Since this device is a superconducting device, it consumes very little power and there is almost no limit to the duration of the experiment. Therefore, by using this apparatus, it is possible to conduct experiments under microgravity for a long period of time, and there are very few restrictions on experiments as in space experiments. In addition to protein crystallization, this device can be applied to other processes such as mixing, which is expected to produce good results when the influence of gravity is suppressed.

  Here, the principle of realizing microgravity by generating a strong magnetic force field will be briefly described. In addition, since the more specific structure of this kind of apparatus is a well-known technique, detailed description is not given here, but patent documents 1-3 and nonpatent literature 1 etc. can be referred as needed.

  Magnetic force is

Can be expressed as Here, B is the magnetic flux density, χ is the volume magnetic susceptibility, and μ ₀ is the vacuum magnetic permeability.

  When only the vertical component (z direction) is viewed in the equation (1), the following equation (2) is obtained.

This magnetic force balances with gravity under the following conditions.

Here, ρ is density and g is gravitational acceleration.

  From this relationship, for example, to cancel the gravity acting on water drops

Is about 1,350 T ² / m. That is, it is possible to create a microgravity environment in which the influence of gravity can be ignored by canceling the gravity with a magnetic force.

  On the other hand, in order to generate such a magnetic force, a very large magnetic flux density or a spatial change of the magnetic flux density is required from the equation (1) or (2). In the case of a normal superconducting magnet on the market,

Is several hundred T ² / m or less, so that the magnetic force is not strong enough to float a water droplet against gravity. For this reason, in the above-mentioned patent documents and non-patent documents, a disc-shaped ferromagnetic body or permanent magnet and a ring-shaped strong magnet are formed along the central axis in the room temperature bore provided in the hollow interior of the superconducting magnet. By arranging the magnetic body or the permanent magnet at an interval, the magnetic field formed in the space between them has been strengthened.

  However, in the conventional magnetic force field generator, the space where microgravity can be provided by generating a strong and uniform magnetic force field is confined to the vicinity of the central axis in the room temperature bore of the superconducting magnet. It was difficult to provide a large-volume microgravity space for performing various experiments or performing multiple experiments with different conditions in parallel.

JP 2003-7525 A JP-A-2005-353860 JP 2006-339493 A

Osamu Ozaki, Tsukasa Kiyoshi, Shinji Matsumoto, Jun-ichi Fujihira, Hitoshi Wada, "Development of a Magnetic Force Booster," IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 14, NO. 2, JUNE 2004.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a magnetic force field generator with a large space capable of providing microgravity by applying a strong and uniform magnetic field.

According to one aspect of the present invention, a ferromagnetic body or a magnetic field of the superconducting magnet is disposed on one side of the axially intermediate position of the central axis inside the hollow of the superconducting magnet with the central axis facing the vertical direction. The following (A) a rotationally symmetric member that is arranged coaxially with the central axis, and (B) that is arranged coaxially with the central axis and is larger than the outer diameter of the rotationally symmetric member. A first ring-shaped member having an outer diameter and disposed so that the position in the vertical direction is different from that of the rotationally symmetric member ; (C) disposed coaxially with the central axis, and from an inner diameter of the first ring-shaped member And a second ring-shaped member disposed so as to have a different vertical position from the first ring-shaped member, and (D) the second ring-shaped member disposed coaxially with the central axis. Larger than the inner diameter of the member A third ring-shaped member that has a large inner diameter and is arranged so that a position in the vertical direction is different from that of the first ring-shaped member , wherein the second ring-shaped member is relative to the first ring-shaped member. The third ring-shaped member is disposed on the same side as the first ring-shaped member in the vertical direction with respect to the second ring-shaped member, and is disposed on the same side as the rotationally symmetric member in the vertical direction. rotationally symmetrical member is accommodated inside the inner circumference of the second ring-shaped member, the first ring-shaped member of the magnetic force field generated, characterized in that it is housed inside the inner periphery of the third ring-shaped member Equipment is given.

  The rotationally symmetric member may be disk-shaped.

  Further, one or more additional ring-shaped members having an inner diameter larger than the inner diameter of the second ring-shaped member may be arranged on the one side of the intermediate position and coaxial with the central axis.

  Further, the additional ring-shaped member may be a plurality of members having different inner diameters.

  With the above configuration, it is possible to generate a strong and uniform magnetic field in a space off the central axis of the room temperature bore, so that a magnetic force field suitable for realizing a microgravity space with a larger volume can be generated. A device is obtained.

It is a perspective view which shows notionally the disk and ring which comprise a strong magnetic force generation | occurrence | production part. It is sectional drawing which shows notionally the disk and ring which comprise the superconducting magnet and the strong magnetic force generation | occurrence | production part installed in the hollow inside. It is a figure which shows the characteristic of the superconducting magnet used for an Example. It is a figure which shows the calculation result of magnetic force distribution at the time of using a permanent magnet as a disk and a ring. It is a figure which shows the calculation result of magnetic force distribution at the time of using a permanent magnet as a disk and a ring. It is a figure which shows the calculation result of magnetic force distribution at the time of using a ferromagnetic material (iron) as a disk and a ring. It is a figure which shows the calculation result of magnetic force distribution at the time of using a ferromagnetic material (iron) as a disk and a ring. It is a figure which shows the calculation result of magnetic force distribution at the time of using a permanent magnet and a ferromagnetic material (iron) together as a disk and a ring. It is a figure which shows the calculation result of magnetic force distribution at the time of using a permanent magnet and a ferromagnetic material (iron) together as a disk and a ring.

  In the “Mode for Carrying Out the Invention” section, the material of the disk and the ring is treated as a material that can replace the ferromagnetic material and the permanent magnet magnetized in the same direction as the magnetic field of the superconducting magnet. In order to avoid such complications, unless otherwise noted in this section, “ferromagnetic material” represents both a ferromagnetic material and a permanent magnet.

  According to one embodiment of the present invention, the strong magnetic force generator is installed in the hollow interior of the superconducting magnet that is arranged so that the central axis faces the vertical direction. As can be seen from FIG. 1 which is a schematic perspective view and FIG. 2 which is a schematic cross-sectional view, in the strong magnetic force generating part, a ferromagnetic disc 1 and a strong magnetic force separated upward from the disc 1 along the central axis. A first ring 2 of magnetic material is arranged symmetrically with respect to the central axis. Further, a ferromagnetic second ring 3 having an inner diameter larger than the outer diameter of the disk 1 is disposed around the disk 1 so as to be symmetrical about the central axis, and the inner diameter of the first ring 2 is around the first ring 2. The ferromagnetic third ring 4 which is larger than the outer diameter of the second ring 3 but smaller than the outer diameter of the second ring 3 is arranged symmetrically with respect to the central axis. These rings 2, 3, 4 and the disk 1 are arranged on one side of the intermediate position in the axial direction of the central axis of the superconducting magnet. In order to make the structure easy to see, FIG. 1 shows only the ferromagnetic disk 1 and the rings 2, 3, and 4 that constitute the strong magnetic force generator, but the sectional view shown in FIG. Also shown is a superconducting magnet that houses the strong magnetic force generator shown in FIG.

  With this configuration, between the disk 1 and the second ring 3 and between the first ring 2 and the third ring 4, respectively, stronger and more uniform than in the case of a superconducting magnet alone. Two regions with a magnetic field are formed. The first region is a region above the disk 1 on the central axis and the first ring 2 does not exist thereon. In addition, the first region is above the second ring 3. Above this, a strong and highly uniform magnetic field is similarly formed in the second region in which neither the first ring 2 nor the third ring 4 exists. Of these two regions, the first region is a region similar to the conventional one on the central axis, and thus its volume is relatively small as in the conventional case. On the other hand, since the second region is a thick ring-shaped region, that is, a donut-shaped region, the second region increases in proportion to the distance from the central axis.

  Furthermore, it is similar to the second region by providing one or more additional larger rings concentrically around the circumference of the second ring 3 and around the third ring 4, respectively. A region having a strong and highly uniform magnetic field such as a third, fourth, etc. having a larger radius can also be formed. Therefore, the present invention does not limit the ferromagnetic ring to the first to third rings 2, 3, 4, and includes a case in which a ring is further provided in addition to these three rings. Should. In such a configuration, since the magnetic force conditions are different between the doughnut-shaped region near the inner periphery and the donut-shape near the outer periphery, each has a large volume and a plurality of magnetic force conditions different from each other. An area can be provided simultaneously.

  In addition, when the relatively small first region located on the central axis is not used, the first ring placed on the first region has a disk-like shape in which the central portion is filled with a ferromagnetic material. It can also be a shape. Alternatively, the first ring may be left as it is or may have a disk shape, and the lower disk may be omitted.

  As described above, in the present invention, a strong and highly uniform magnetic field can be generated in a donut-shaped region located off the central axis, so that microgravity can be provided in this large region. .

  It should be noted that even if such a region is generated on the central axis of the conventional configuration, it is conceivable to provide a large volume region by stacking such structures in the vertical direction along the central axis. It has the following problems. That is, when conventional structures are stacked in the vertical direction, it becomes difficult to access areas other than the uppermost part. Therefore, for example, taking the case of crystal growth as an example, installation and removal of the equipment for that purpose becomes very complicated, so that the productivity of crystal growth work is reduced, and the state of crystal growth is observed. Therefore, there is a disadvantage that it is necessary to insert a special instrument for this purpose through a narrow place.

  Examples of the present invention will be described below, but the present invention is of course not limited thereto.

  The following shows the calculation results of the magnetic force based on the specific size, the ratio of the size between various elements, the vertical and horizontal positional relationship, and the material used, etc. The magnitude and uniformity of the force changes. Therefore, the vertical and horizontal positional relationships between various elements are examples, and when designing and manufacturing a magnetic force field generator, the positional relationship, mutual size, materials used, etc. should be individually optimized. Can do.

  As a superconducting magnet, a solenoid coil with a length of 30 cm having a magnetic field of 10.2 T at the center of the magnetic field, whose characteristics are shown in FIG. 3, is assumed, and based on this, the magnetic force distribution in each case shown below was calculated. The results are shown as examples.

In FIG. 3, the horizontal axis represents the distance (cm) from the midpoint of the solenoid coil in the vertical direction (sometimes referred to as the z direction), that is, from a point at a position of 15 cm from both the upper end and the lower end. The vertical axis on the right side represents the magnetic field (T) on the central axis at that distance (corresponding to the one-point difference line graph), and the left axis is also the perpendicular magnetic force (T ² / m) on the central axis (solid line). Corresponding to the graph). In the calculation shown below, the position range of the strong magnetic force generation region in the strong magnetic force generation part (more specifically, the first ring and the upper surface of the disk and the second ring in the strong magnetic force generation part) The position range of the region in the range up to the lower surface of the third ring) is said to be in the range of 11 cm to 12 cm upward, but it depends on the degree of gravity cancellation and the specific configuration of the magnetic force generator. It can also be set as the range.
(1) When a permanent magnet is used as a disk and a ring Here, the magnetization is 1.4T, which is magnetized in the same direction as the magnetic field of the superconducting magnet (that is, the direction of magnetization is directed to the same direction as the magnetic field of the superconducting magnet). The magnetic force distribution was calculated using the permanent magnets. FIG. 4 shows the entire calculated magnetic force distribution. Here, 1 is a disk, 2 is a first ring, 3 is a second ring, 4 is a third ring, and 5 is an iron block placed on the outermost periphery. FIG. 5 shows the perpendicular magnetic force distribution (denoted as center) on the central axis and the upper surface of the lower ring for the above-described region (11 cm to 12 cm) of the strong magnetic force generation region (horizontal axis z in the figure). The vertical magnetic force distribution (24.4 and 24.4 and the central portion of the second strong magnetic force generation region, which is the lower side of the gap between the two upper rings, is displaced by 2.44 cm from the central axis. Notation).

As can be seen from FIG. 5, the perpendicular magnetic force is about 1450 T ² / m on the central axis (that is, the first region) in the first region and the second region with z = 11 to 12 cm, and is horizontal from the central axis. In the second region which is 2.44 cm away in the direction, it is slightly lower than that, but at about 1250 T ² / m, both of which are almost uniform. In FIG. 5, it is considered that the perpendicular magnetic force plot on the central axis is disturbed from near z = 11 cm down due to a calculation error. Further, as shown in FIG. 4, the central axis is set by an iron block 5 that is spaced apart from the second ring 3 and extends upward to the height of the lower surface of the first ring 2 and the second ring 3. The magnetic force uniformity at a position 2.44 cm away from the horizontal direction was improved, but the magnitude of the magnetic force decreased.
(2) When using a ferromagnet as a disk and ring The size of each part is the same as when using the permanent magnet of (1), but the disk and ring are not permanent magnets. The case where iron (saturation magnetization 21T) was used was calculated. The results corresponding to FIGS. 4 and 5 are shown in FIGS. 6 and 7, respectively. As can be seen from FIG. 7, in this case, the perpendicular magnetic force was not so constant at z = 11 to 12 cm as compared with FIG.
(3) When a permanent magnet and a ferromagnet are mixed as a disk and a ring Although the size of each part is the same as the above two cases, the lower disk and ring are magnetized in the same direction as the magnetic field of the superconducting magnet The case where a permanent magnet (magnetization 1.4T) was used and iron (saturation magnetization 19T) was used for the upper two rings was calculated. The calculation results corresponding to FIGS. 4 and 6 described above are shown in FIG. 8, and the calculation results corresponding to FIGS. 5 and 7 are shown in FIG. In this configuration, as can be seen from FIG. 9, a perpendicular magnetic force distribution with higher flatness was obtained compared to the above two calculation examples.

  As described above in detail, according to the present invention, a microgravity region having a large volume can be realized with a simple configuration, so that a great contribution is made to a wide range of fields that require a microgravity environment. is there.

DESCRIPTION OF SYMBOLS 1 Disc 2 1st ring 3 2nd ring 4 3rd ring 5 Iron block

Claims (4)

From a permanent magnet magnetized in the same direction as the magnetic field of the ferromagnetic body or the superconducting magnet on one side of the axially intermediate position of the central axis inside the hollow of the superconducting magnet with the central axis facing the vertical direction (A) a rotationally symmetric member disposed coaxially with the central axis,
(B) A first ring-shaped member that is disposed coaxially with the central axis, has an outer diameter larger than the outer diameter of the rotationally symmetric member, and is disposed so that the position in the vertical direction is different from that of the rotationally symmetric member. ,
(C) the centrally disposed axis coaxially, said and having an inner diameter larger than the inner diameter of the first ring-shaped member, wherein the first ring-shaped member second rings vertical position are arranged differently Shaped member, and
(D) A third ring that is arranged coaxially with the central axis, has an inner diameter larger than the inner diameter of the second ring-shaped member, and is arranged so that the position in the vertical direction is different from that of the first ring-shaped member. Shaped member,
Equipped with a,
The second ring-shaped member is arranged on the same side as the rotationally symmetric member in the vertical direction with respect to the first ring-shaped member,
The third ring-shaped member is arranged on the same side as the first ring-shaped member in the vertical direction with respect to the second ring-shaped member,
The rotationally symmetric member is housed inside the inner periphery of the second ring-shaped member;
The magnetic force field generator according to claim 1, wherein the first ring-shaped member is accommodated inside an inner periphery of the third ring-shaped member .   The magnetic force field generating apparatus according to claim 1, wherein the rotationally symmetric member has a disk shape. The one or more additional ring-shaped members having an inner diameter larger than the inner diameter of the second ring-shaped member are arranged coaxially with the central axis and on the one side of the intermediate position. Item 3. The magnetic force field generator according to Item 1 or 2 . The magnetic force field generator according to claim 3 , wherein the additional ring-shaped member is a plurality of members having different inner diameters .