JP2001062337A - Nonferrous metal material classifying method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To classify nonferrous metal materials having smaller diameters, by arranging magnetic lines of force generated from a first permanent magnet element to turn toward the radius direction of a rotor, and arranging magnetic lines so that they may repel the magnetic lines of force generated from a second permanent magnet element to efficiently turn toward the outside of the rotor. SOLUTION: A magnet element 23 consists of a first permanent magnet element 24 in the shape of a square hexahedron and a second permanent magnet element 25 in the shape of a hexahedral trapezoid. The magnet element 24 is disposed in the shaft direction of a rotor. The magnet elements 24 is arranged so that its magnetic poles turn toward the outside from the center of the rotor along the radius direction. As for the magnetic poles turning toward the outside of one line of the magnet element 24, they are arranged alternately, as N-pole S-pole, N-pole,.... Each of the magnet element 25 is disposed between the lines of the magnet elements 24. The magnetic poles of each magnet element 25 are arranged to turn toward the same magnetic poles of each magnet element 24. In such arrangement, magnetic lines of force generated from the magnet element 24 repels magnetic lines of force generated from the magnet element 25 to efficiently turn toward the outside of the rotor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for separating non-ferrous metals from non-ferrous metals.
More specifically, the present invention relates to a non-ferrous separation method for separating non-ferrous metal objects by repulsion caused by eddy currents generated in the metal objects and an apparatus therefor. More specifically, the present invention relates to a method of assembling a magnet element fixed on an outer peripheral cylindrical surface of a rotor to generate an eddy current in a metal object to provide a magnetic field.

[0002]

2. Description of the Related Art Industrial waste, waste home appliances, and waste buildings contain many valuable metals, and it is important to separate and reuse such metals. In addition, there are metal objects in foods and foodstuff materials that also contain all kinds of impurities, and it is also desired to remove the metal objects. Among these metallic materials, iron-based iron, nickel, cobalt, martensite of stainless steel, etc. can be removed and separated by adsorption with a magnet or the like, but non-ferrous metallic materials such as aluminum, copper and brass can be used. It cannot be separated and removed only by magnets.

An eddy current type is known as a method and an apparatus for separating these nonferrous metal objects. When an electric conductor is placed in a time-varying magnetic field, an induced electromotive force is generated inside the metal under the influence of the time-varying magnetic field, and thus an eddy current flows. The induced magnetic field caused by the eddy current interacts with the original magnetic field to generate a repulsive force. The eddy current type metal sorting apparatus utilizes repulsion caused by the eddy current.

The principle of operation of the eddy current type non-ferrous metal object sorting apparatus will be described with reference to FIG. FIG. 6A illustrates the principle of generation of a repulsive force due to an eddy current. When the conductor penetrates the magnetic flux, electromagnetic induction electromotive force is generated in the conductor due to the temporal change of the magnetic flux, and an eddy current flows. This eddy current creates an induced magnetic field, which interacts with the original magnetic field. According to Lenz's law, eddy currents are generated in a direction to cancel the original magnetic field. That is, when the magnetic flux penetrating through the conductor increases with time, the direction of the magnetic flux lines of the induction magnetic field is opposite to the direction of the magnetic flux lines of the original magnetic field, and they repel each other. In the opposite case, the induced magnetic field and the original magnetic field are attracted. As described above, the repulsive force generated when the induced magnetic field repels the original magnetic field becomes a source of the force for bouncing off the conductor. Producing such a repulsion acts in exactly the same way for a conductor placed in a changing magnetic field.

FIG. 6 (b) illustrates the principle of an eddy current type non-ferrous metal sorting apparatus. The objects are transported on a belt moving at a constant speed to a rotor which provides an alternating magnetic field. The rotor is rotating at high speed with respect to the belt. A permanent magnet is fixed on the outer peripheral cylinder of the rotor, and the rotor rotates to generate an alternating magnetic field on the object to be sorted on the belt. According to the above-described principle, an eddy current is generated in the non-ferrous metal object and is bounced off. When falling off by bouncing, the distance varies depending on the type and size of the metal. If all of the objects to be sorted are the same size, the falling distance differs depending on the type of metal, so that sorting can be performed for each metal. The distance to fall depends on the initial bouncing force and the density of the object to be sorted.

The induced electromotive force e generated in the object to be sorted is represented by the following equation. e = −k dB / dt (Equation 1) where B is the magnetic flux line density of the magnetic field, k is a constant, t is time,
d is a differential operator. The eddy current i flowing in the object to be sorted is as follows. i = e / R =-(k / R) dB / dt (Equation 2) R: electric resistance of the object to be selected The eddy current i generates an induced magnetic field proportional to the electric current. An eddy current is generated such that the induced magnetic field cancels the change in the original magnetic field (Lenz's law).

When the change in the magnetic flux penetrating the object to be sorted is large in time, the induced magnetic field and the original magnetic field repel each other. The magnitude of the repulsive force depends on the change in the magnetic flux density passing through the object to be sorted, as is apparent from the above equations (1) and (2).
In order to increase the repulsion, it is necessary to increase the change in magnetic flux density.

As shown in FIG. 4 (a), when a permanent magnet is mounted on an outer peripheral cylinder of a rotor, conventional magnets are arranged such that N poles and S poles of magnet elements alternately face outward. are doing. In this conventional structure, there are the following methods for increasing the change in magnetic flux density. 1. 1. Increase the relative speed between the sorted object and the permanent magnet element; 2. Use a strong magnetic field for the permanent magnet element. This is a method of increasing the volume of the sorting object.

The above-mentioned method 1 is a method of increasing the speed of the belt, increasing the rotation speed of the rotor, or both. In the case of the above-mentioned method 2, the more expensive the magnet, the higher the price of the device, which is not suitable for mass production. In the case of the above-mentioned method 3, there is a drawback that it is not possible to sort small-sized ones.

As described above, in the conventional structure, the magnetic field lines are parabolic from the north pole to the south pole of the magnet element.
The number of lines of magnetic force that the sorting object penetrates is limited. If the object to be sorted passes as close as possible to the permanent magnet element, the number of magnetic fluxes penetrating increases, but there is a structural limit in the actual machine stage.

[0011] In the conventional structure, when the volume of the object to be sorted is reduced, the object is moved backward from the vicinity of the rotor (so as to flow backward).
Being bounced off. This is because the repulsive force for reducing the volume becomes larger than its own weight and the object rebounds.

[0012]

SUMMARY OF THE INVENTION The present invention has been made under the above-mentioned technical background, and achieves the following objects. An object of the present invention is to provide a more efficient non-ferrous metal sorting apparatus. It is another object of the present invention to provide a method and an apparatus which can sort a smaller volume than a conventionally unsortable one by a combination structure of permanent magnet elements. Still another object of the present invention is to provide a structure of a belt conveyor in which an object to be sorted does not flow on the belt conveyor in a reverse direction.

[0013]

The present invention employs the following means to achieve the above object. The object is achieved by arranging the permanent magnet elements so that the lines of magnetic force generated from the permanent magnet elements are generated in the radial direction of the rotor. The arrangement is as follows. Permanent magnet elements are arranged on the outer peripheral cylinder of the rotor such that N poles and S poles alternately face outward in the radial direction of the rotor, while another magnetic element faces the outside of the magnet element. Sideways so that the same pole faces. A yoke is sandwiched between the side surfaces of the magnets having alternately arranged magnetic poles, and a trapezoidal magnet is inserted therebetween. The magnetic poles of the trapezoidal magnets are mounted such that the upper part repels the magnetic poles of the left and right magnets, and the lower part attracts. In this arrangement, since the same poles of the magnet elements face each other, they repel each other, and the magnetic force lines are directed outward in the radial direction. Further, in order to prevent the sorted objects flowing on the belt conveyor from flowing in the opposite direction under the influence of the repulsive force, the above-mentioned object is achieved by lowering the belt conveyor. In order to improve the magnetic flux density of the magnetic field provided by the eddy current generator, the present invention provides a method of arranging magnet elements mounted on an outer peripheral cylinder of a rotor and a belt conveyor so that small conductors do not flow backward due to repulsion due to eddy current. In a downhill state.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment of the Invention]
An embodiment of the present invention will be described. FIG. 1 is an overall view showing a first embodiment of the present invention. FIG. 2 is a front sectional view of the rotor portion. FIG. 3 is a view showing an arrangement of magnet elements in a circumferential direction. As shown in FIG. 1, the present non-ferrous metal sorting apparatus 1 includes a frame 2 that accommodates the non-ferrous metal sorting apparatus 1, a belt conveyor 3 mounted thereon,
It is composed of a motor 4, a rotor 5, a hopper 6, and the like. The frame 2 is the main body of the present apparatus. The belt conveyor 3 is a transfer device that transfers the materials to be sorted. The motor 4 drives the rotor 5 to rotate via a timing belt or the like. The rotor 5 provides a changing magnetic field for sorting non-ferrous metals. The hopper 6 is for supplying a selected material to the belt conveyor 3 in a fixed amount. The belt conveyor 3 has a tail pulley 7 on the side opposite to the rotor 5.
Is arranged. The tail pulley 7 incorporates a built-in motor (not shown), and drives the belt conveyor 3 by this motor. The entire non-ferrous metal object sorting apparatus 1 is covered with a cover 8. Inside the cover 8, a sorting box 9 for storing the sorted non-ferrous metal objects
Is arranged. On the sorting box 9, a partition 10 for sorting is arranged.

FIG. 2 shows a magnet element arranged on the outer periphery of the rotor 5. The magnet element 23 is a permanent magnet, and in this embodiment, is a neodymium permanent magnet. FIG. 3 is a view showing an arrangement of magnet elements in a circumferential direction. Magnet element 23 is square 6
It is composed of two types: a magnet element 24 of a face body and a trapezoidal magnet element 25 of a hexahedron. The outer periphery of the rotor 5 is formed with 18 cylinders 20, and one surface of the magnet element 24 is fixed on each of the 18 cylinders. The magnet element 24 is arranged in the axial direction of the rotor 5. The magnet element 24 is fixed so that its magnetic pole faces radially outward from the center of the rotor 5. Further, the magnetic poles that are fixed to the adjacent surfaces and that face outward from each other are opposite to each other. That is, the magnetic poles facing the outside of the magnet elements 24 in one row are N poles,
Poles, north poles,...

A magnet element 25 is arranged between each row of magnet elements 24 (first permanent magnet elements). Magnet element 2
The magnetic pole of No. 5 (second permanent magnet element) is arranged facing the same magnetic pole side of the magnet element 24. With this arrangement, the magnetic pole of the magnet element 24 on the rotor 5 side attracts the magnetic pole of the magnet element 25, and the opposite magnetic pole repels the magnetic pole of the magnet element 25. As a result, a structure that does not require a fixing operation such as screwing by the force for pushing the magnet element 25 toward the rotor 5 side. The eighteenth cylinder 20 is made of yoke. Therefore, the lines of magnetic force from the magnetic poles of the magnet element 24 and the magnet element 25 on the rotor side do not leak to the outside through only the inside of the yoke. Lines of magnetic force emanating from the outwardly facing poles leak around the rotor 5 and provide a magnetic field in the radial direction of the rotor 5. FIG.
4 (a) and 4 (b) show the state of the lines of magnetic force.
(A) is a diagram showing the state of the magnetic field lines of the conventional magnet arrangement, and FIG. 4 (b) is the result of measuring the state of the magnetic field lines of the present invention with a Gauss meter. b). Lines of magnetic force generated from each magnetic pole of each magnet element 23 are all directed outward. Therefore, it is apparent that the number of lines of magnetic force penetrating the object to be sorted is significantly increased as compared with the conventional structure.

The objects to be sorted supplied from the hopper 6 are transported to the rotor 5 on the belt conveyor 3. In the vicinity of the rotor 5, an induced electromotive force is generated in the object to be sorted under the influence of the magnetic field that is changed by the rotation of the rotor 5 by the permanent magnet 23,
Eddy currents flow. Eddy currents create an induced magnetic field. This induced magnetic field is in a direction to cancel the original magnetic field (Lenz's law). Therefore, the induced magnetic field interacts with the original magnetic field. When this interaction repels, the object is bounced off.
The object to be bounced off falls while falling freely. The distance to fall depends on the type and size of the metal object. If the sizes of the objects to be sorted supplied from the hopper at the beginning are all the same, the objects to be metalized can be classified by type based on the above-mentioned falling distance. [Second Embodiment of the Invention] FIGS. 5A and 5B show a second embodiment of the present invention, and FIG.
FIG. 5B is a front view. The configuration of the second embodiment is basically the same as that of the first embodiment. The difference is that the belt conveyor 33 that conveys the objects to be sorted has a structure that is inclined just before the rotor. The operation of the other components is exactly the same as in the first embodiment. That is, the auxiliary roller 70 is disposed immediately before the rotor 5, and the supporting members 71 are disposed at both ends of the auxiliary roller 70 to support the auxiliary roller 70. By providing the belt conveyor 33 with an inclination so as to protrude upward by the auxiliary roller 70, an object to be sorted is moved away from the rotor 5 before sorting, so that the object to be separated is jumped to the belt conveyor in the opposite direction to the belt conveyor 33 under repulsive force. , To prevent rolling. When the weight of the sorted material decreases,
While approaching the rotor 5, it was blown backward or flowed under repulsion. Therefore, such a phenomenon does not occur when the belt conveyor 33 is inclined near the rotor 5. When the objects to be sorted fall one by one from the slope, they may be bounced backward. However, since the objects to be sorted are caught by the objects to be washed flowing from behind, the above-described problem does not occur.

[0018]

According to the present invention, the following effects can be obtained.
The magnet element is arranged on the outer circumferential circle of the rotor so that the north pole and the south pole alternately face outward with respect to the axial direction of the rotor.
By arranging the N pole of the magnet element facing the magnet element facing the pole side, the magnetic lines of force created by the magnet element are no longer flat, and the rotation of the rotor causes a sharp change in the magnetic flux density. The eddy current in the sorted object increases, and the repulsive force caused by the eddy current increases,
The sorting efficiency of the sorting objects has increased, and smaller objects can be sorted. Also, by making the rotor-side portion of the belt conveyor, which is a means for transporting the sorted material, a slope, the sorted material does not flow backward from the rotor portion,
The efficiency of sorting increased.

[Brief description of the drawings]

FIG. 1 is an overall view showing a first embodiment of the present invention.

FIG. 2 is a front sectional view of a rotor portion.

FIG. 3 is a diagram showing an arrangement of magnet elements in a circumferential direction.

4 (a) and 4 (b) show the state of the magnetic field lines, FIG. 4 (a) shows the state of the magnetic field lines of a conventional magnet arrangement, and FIG. It is a figure showing the state of the line of magnetic force of the present invention.

5 (a) and 5 (b) show a second embodiment of the present invention. FIG. 5 (a) is a plan view and FIG. 5 (b) is a front view.

FIGS. 6A and 6B are diagrams showing the principle of eddy current generation and the principle of an eddy current type metal object sorting apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Non-ferrous metal separation apparatus 2 ... Frame 3 ... Belt conveyor 4 ... Motor 5 ... Rotor 6 ... Hopper 7 ... Dale pulley 8 ... Cover 21 ... Main shaft 22 ... Outer cylinder 20 ... Yoke ring 23 ... Permanent magnet element 24 ... Magnet Element 25: trapezoidal magnet 26: yoke spacer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F201 AA50 AQ03 BA04 BC01 BC02 BC12 BC25 BC37 BN32 BP08 BP26

Claims (4)

[Claims] A permanent magnet element (23) is alternately provided with S-poles and N-poles in a circumferential direction of an outer periphery of a rotor (5), and the rotor (5) is driven to generate an alternating magnetic field to produce a non-ferrous metal. An eddy current type non-ferrous metal object sorting method comprising eddy current generating means for generating an eddy current in an object, wherein the first permanent magnet constituting one of the permanent magnet elements (23) of the eddy current generating means The magnetic field lines generated from the first permanent magnet element (24) are arranged such that the magnetic field lines generated from the element (24) are directed in the radial direction of the rotor (5).
A vortex, which is arranged so as to be repelled by magnetic lines of force generated from a second permanent magnet element (25) constituting the other of the permanent magnet elements (23) and efficiently face the outside of the rotor (5). Galvanic non-ferrous metal separation method. 2. A permanent magnet element (2) is provided around an outer periphery of a rotor (5).
3) The S pole and the N pole are alternately attached to the rotor (5).
An eddy current type non-ferrous metal sorting apparatus comprising an eddy current generating means for generating an eddy current for generating an alternating magnetic field by driving an eddy current to separate non-ferrous metal objects, Eddy current generating means for alternately mounting S and N poles on the permanent magnet elements (23) and driving the rotor (5) to generate an alternating magnetic field to generate an eddy current in the non-ferrous metal object; A magnetic spacer (26) is sandwiched between the side surfaces of the first permanent magnet elements (24), and the second permanent magnet elements (2
5) is arranged so that the magnetic field lines generated from the first permanent magnet element (24) are repelled by the magnetic field lines generated from the second permanent magnet element (25) so as to efficiently face the outside of the rotor (5). An eddy current type non-ferrous metal object sorting device, wherein the device is disposed in a pit. 3. An eddy current type non-ferrous metal sorting apparatus according to claim 2, wherein said first permanent magnet element (24) is a rectangular parallelepiped on six sides, and said second permanent magnet element (23) is ) Is an eddy current type non-ferrous metal sorting apparatus characterized by having a trapezoidal shape on six sides. 4. An eddy current type non-ferrous metal sorting apparatus according to claim 2, wherein a non-metallic belt conveyor for transferring the non-ferrous metal to the eddy current generating means. And a driving device for driving the belt conveyor (3), wherein the belt conveyor (3) is located in front of the eddy current generating means and the permanent magnet element of the rotor (5). (23) An eddy current type non-ferrous metal object separation device, which is configured to be further away from (23).