SUPERCONDUCTING MAGNET APPARATUS USING MOVABLE IRON CORE AND INDUCTION HEATING APPARATUS THEREOF

Abstract

The present invention relates to a superconducting magnet apparatus using movable iron core and induction heating apparatus thereof. The superconducting magnet structure is composed by including a pair of superconducting magnets and a pair of movable iron cores which are symmetrically located with respect to the heating target product located between the superconducting magnets and a part of which move through the cutouts of the superconducting magnets. And the distance from the superconducting magnets is adjusted by moving the movable iron cores. Further, the present invention manufactures an induction heating apparatus by using the superconducting magnet structure.

Claims

1. A superconducting magnet apparatus using movable iron core comprising: a pair of superconducting magnets; and a pair of movable iron cores which are symmetrically located with respect to a heating target product located between the superconducting magnets and a part of which move through the cutouts of the superconducting magnets, and adjust the distance from the superconducting magnets by moving the movable iron cores.

2. The superconducting magnet apparatus using movable iron core of claim 1, wherein the superconducting magnets have a circular shape, a race track shape.

3. The superconducting magnet apparatus using movable iron core of claim 1, wherein the center magnetic field of the heating target product is 1.18 (T) when an operation current is 80% of the critical current of the superconducting magnets.

4. The superconducting magnet apparatus using movable iron core of claim 1, wherein the magnetic field value of the heating target product is generated more than twice as much as that of the superconducting magnet structure in which the movable iron core is not provided.

5. An induction heating apparatus comprising: a pair of superconducting magnets in which movable iron cores are respectively provided; a heating target product located between the superconducting magnets; and an operating unit that rotates the heating target product.

6. The induction heating apparatus of claim 5, further comprises a cryogenic freezer inside of which the superconducting magnets are equipped; and a replaceable fixture which allows the heating target product having different external sizes to be located between the pair of the superconducting magnets, wherein the cryogenic freezer is composed of an inner cryostat and an outer cryostat.

7. The induction heating apparatus of claim 6, wherein the distance between the superconducting magnets and the heating target product is 50 mm.

8. The induction heating apparatus of claim 6, wherein the heating power applied to the heating target product is four times or more higher than that of the induction heating apparatus to which the superconducting magnet structure in which the movable iron core is not provided.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 is a drawing illustrating a superconducting magnet of general race track type.

[0029] FIG. 2 is a drawing illustrating a superconducting magnet in which a movable iron core is applied according to an example.

[0030] FIG. 3 is a floor plan illustrating an induction heating apparatus according to an example.

[0031] FIG. 4A and FIG. 4B are drawings showing examples of mounting on a replaceable fixture for a heating target product having different external sizes.

METHOD FOR CARRYING OUT THE INVENTION

[0032] The present invention can adjust the distance between the heating target product and the movable iron core to be always at the optimum distance by applying the superconducting magnet structure using the movable iron core and the superconducting magnet structure to the induction heating apparatus. Therefore, the heating electric power for the heating target product can be further improved as compared with the prior art while maintaining the highest magnetic field value at all times.

[0033] And the induction heating apparatus according to the present invention refers to a direct current (DC) induction heating apparatus. The induction heating device refers to a device that heats a heating target product to be heated to a desired temperature in a uniform magnetic field. The uniform magnetic field can be obtained when a DC current is supplied to the superconducting magnet, and the larger the magnetic field generated in the superconducting magnet, the larger the energy transfer becomes possible. Of course, the magnetic field increases in proportion to the current flowing through the superconducting magnet, the number of turns, and the number of coils and decreases in inverse proportion to the distance to the heating target product. Therefore, as the distance between the superconducting magnet and the heating target product becomes closer, a larger magnetic field can be obtained and the transferrable energy becomes larger. Accordingly, the present invention proposes a superconducting magnet using a movable iron core and an induction heating apparatus thereof so that the heating target product can always be heated at the maximum electric power while maintaining the highest magnetic field value.

[0034] Further, in the present invention, the shape of the superconducting magnet is not limited to the shape of the race track, but a superconducting magnet having a difference shape such as a circular shape can be applied.

[0035] Hereinafter, an exemplary embodiment of semiconducting magnet apparatus using movable iron core and induction heating apparatus thereof according to the present invention will be described in detail with reference to the accompanying drawings.

[0036] FIG. 2 is a drawing illustrating a superconducting magnet in which a movable iron core is applied according to an example.

[0037] To explain, in the superconducting magnet structure 100, a pair of superconducting magnets 110 and 110′ are arranged. The pair of superconducting magnets 110 and 110′ have a shape of race track type. Of course, as for the type of superconducting magnet, as described above, a superconducting magnet formed in a circle shape other than a race track shape can be applied. Hereinafter, the pair of superconducting magnets will be explained as a first semiconducting magnet 110 and the second superconducting magnet 110′.

[0038] The first superconducting magnet 110 and the second superconducting magnet 110′ are spaced apart from each other.

[0039] A heating target product 120 is located between the first superconducting magnet 110 and the second superconducting magnet 110′. The heating target product 120, a non-magnetic material, may be aluminum, copper, or the like. According to an example, the heating target product 120 is formed in a cylindrical shape and may be referred to as a metal billet.

[0040] The movable iron cores 130 and 130′ are provided so as to be symmetrical with respect to the heating target product 120. The movable iron core is also provided as a pair and the first movable iron core 130 is disposed on the first superconducting magnet 110 and the second movable iron core 130′ is disposed on the second superconducting magnet 110′. The first movable iron core 130 and the second superconducting iron core 130′ are formed in the same shape and size as each other, and are formed as a hexahedron in the example. The first movable iron core 130 and the second movable iron core 130′ are located symmetrically with respect to the heating target product 120 at the center. Also, the parts of the first movable iron core 130 and the second movable iron core 130′ are positioned through the cutouts 112 and 112′ of the first superconducting magnet 110 and the second superconducting magnet 110′. Although the first movable iron core 130 and the second movable iron core 130′ are illustrated as in contact with the heating target product 120, since the first movable iron core 130 and the second movable iron core 130′ are installed movably in one direction, the distance from the heating target product 120 is adjusted. Preferably, the distance becomes a distance at which the heating target product 120 can always maintain the highest magnetic field value according to the external size of the heating target product 120.

[0041] FIG. 3 is a floor plan illustrating an induction heating apparatus according to an example.

[0042] In the induction heating apparatus 200, two cryogenic freezers 210 and 220 are provided symmetrically with respect to the heating target product in order to block heat intrusion from the outside. The cryogenic freezers 210 and 220 are provided to provide a minimum condition for maintaining the superconducting properties of the first superconducting magnet 110 and the second superconducting magnet 110′ and, generally, it is a device for creating and maintaining a low temperature environment. For this purpose, each of the cryogenic freezers 201 and 220 includes a combination of an inner cryostat 212 and the outer cryostat 214 and 224.

[0043] The heating target product 120 is located between the cryogenic freezers 210 and 220.

[0044] And the heating target product 120 is connected to the motor shaft of the driving motor 230 at one side and rotated at a constant speed by driving of the driving motor 230. Of course, the heating target product 120 should be installed by a separate bracket 122 or so forth.

[0045] Further, the first movable core 130 and the second movable core 130′ are located at a regular distance (d) from the heating target product 120. The first movable iron core 130 and the second movable core 130′ have a structure that it is possible to move in one direction through the cutouts (112, refer to the FIG. 2) of the first superconducting magnet 110 and the second semiconducting magnet 110′. Therefore, it is possible to adjust the distance (d) from the heating target product 120 according to the size of the heating target product 120.

[0046] An example of installing the heating target product according to the external size of the heating target product 120 can be seen with reference to FIG. 4. FIG. 4A and FIG. 4B are drawings showing examples of mounting on a replaceable fixture for a heating target product having different external sizes.

[0047] Referring to the FIGS, it can be identified that a replaceable fixture 250 having different sizes is provided for installing the heating target product 120 according to the external size of the heating target product 120. And the first movable iron core 130 and the second movable iron core 130′ are moved in the state where the heating target product 130 is mounted in the replaceable fixture 250 to adjust the separation distance. The distance becomes a distance at which the heating target product 120 can maintain the highest magnetic field value.

[0048] The performance of the induction heating apparatus provided with the movable iron core according to the present invention was compared with that of the conventional induction heating apparatus without the movable iron core.

[0049] As the experimental conditions, the superconducting magnets applied to the induction heating apparatus of the present invention and the conventional induction heating apparatus were designed to have the same size and usage amount. And the current which was 80% of the critical current of the superconducting magnet was regarded as the operation current. Further, the distance between the heating target product and the superconducting magnet was modelled as 50 mm.

[0050] As a result of the experiment, the center magnetic field of the conventional heating target product was 0.58 (T), and the center magnetic field of the heating target product of the present invention was 1.18 (T) as shown in the below Table 1. Accordingly, when the same superconducting magnet length and outer size are applied, it can be seen that a magnetic field value twice as large is generated to the heating target product. This results in a result that the heating power can be improved four times or more.

TABLE-US-00001 TABLE 1 Superconducting Magnet Structure Maximum Magnetic Field [T] The magnetic field value of the heating 0.58 target product with superconducting magnets without movable iron core (Conventional Technology) The magnetic field value of the heating 1.18 target product with superconducting magnets with movable iron core (Present Invention)

[0051] Like this, if an induction heating apparatus is manufacture with superconducting magnets with movable iron core, the heating target product can be heated at the maximum electric power as it is possible to maintain the distance between the heating target product and the superconducting magnets at the optimal distance.

[0052] As explained above, according to an example of the present invention, it is possible to secure a heating power about four times higher than that of the superconducting magnet without the movable iron core and to maintain the maximum output in all specifications regardless of the size of the heating target product by applying the movable iron core to the superconducting magnet. Furthermore, as the result of the experiment shows, it was confirmed that the magnetic field value of the heating target product was about twice or more higher than that of the conventional one under the same conditions. It can be objectively confirmed that the purchase cost of the superconducting wire can be reduced and the manufacturing cost of the induction heating apparatus can be reduced as well.

[0053] While this invention has been described in terms of its characterization, structure, and effects in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. Furthermore, the described characterization, structure, and effects of the embodiments may be modified in various different ways by those skilled in the art. And these differences related to modifications and applications are intended to be included within the scope of the present disclosure as defined in what is claimed.

INDUSTRIAL APPLICABILITY

[0054] The present invention applied superconducting magnets with movable iron cores applied to the induction heating apparatus. Accordingly, it is possible to maintain the distance between the heating target product and the movable iron core at an optimal distance by moving the movable iron core according to the external size of the heating target products. As a result, since the heating target product can always generate the highest magnetic field value, the product can be heated by improving the heating power for the heating target product. Namely, it is possible to generate twice or more magnetic field compared to the superconducting magnet structure of the conventional race track shape (for instance, magnet structure without the movable iron core).

[0055] Therefore, an example of the present invention enables manufacturing of an induction heating apparatus with improved capacity while using less superconducting wires and thus can reduce the purchasing cost of the superconducting wire and manufacture an induction heating apparatus at a lower cost.