RU2405164C1 - Device for measuring force interaction of ferromagnetic toroids - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: device for measuring force interactions of ferromagnetic toroids consists of a housing, in the bottom part of which there is a first ferromagnetic toroid with its displacement mechanism, and in the top part there is a second ferromagnetic toroid placed coaxially and mechanically linked to a calibrated twisting-compression spring. The second end of the said spring is attached to the top part of the cylindrical housing. Also said toroids are mechanically linked to displacement and shaft rotation angle sensors, which in turn are connected to an information processing unit.

EFFECT: invention is aimed at measuring vertical and horizontal magnetisation components in a pair of ferromagnetic toroids.

5 dwg

Description

The invention relates to the field of physics of magnetism and can be used in the synthesis of ferromagnetic toroids with non-standard magnetization.

The use of permanent magnets in the form of ferromagnetic toroids, the magnetic poles of which are located on their end surfaces, and the magnetic field lines are orthogonal to these end surfaces, is widely known. In particular, such magnets are used in traveling (backward) wave tubes in microwave technology and in the production of electrodynamics for sound-reproducing equipment. The magnetization of such ferromagnetic toroids is carried out by placing them axisymmetrically in solenoids with a magnetizing direct current, the magnitude of which creates a saturating magnetic field in the solenoids for the toroidal ferromaterials. Moreover, in the ferromaterial having a high coercive force, a sufficiently high residual magnetization is created after the cessation of the direct current in the solenoid, and the distribution of magnetic field lines that was in the solenoid with a direct magnetizing current [1-3] is also memorized due to the alignment of the magnetic domains of a ferromagnet along the lines of a saturating magnetic field. The strongest magnets are created using ferrites, the chemical formula of which contains rare-earth elements, for example, CoSm ₃ ferrites, for which the product of magnetic induction by magnetic field strength (HV) _MAX reaches 320 T. kA / m (40 million GS.e) .

The ability of the magnetic domains of ferromagnets to maintain the direction of magnetization in the direction of the magnetizing external magnetic field after turning off the latter is well known and used in the claimed technical solution.

Permanent magnets in the form of ferromagnetic toroids with oblique magnetization (author terminology) have not been considered in the known literature. The magnetic lines of force in such permanent magnets are not orthogonal to the plane of the ends of the toroid, but are tilted relative to the verticals to any point of these planes at an angle φ lying in the plane passing through this vertical and tangent to the circle, coaxial to the axis of symmetry of the toroid and passing through this point on the plane of the end face of the magnet, and the countdown of the angles φ relative to their verticals in the given plane of the end face of the magnet can be clockwise or counterclockwise for all points of this plane. This type of magnetization of a ferromagnetic toroid is carried out by placing the latter in a complex external saturating magnetic field, which is formed when a winding is wound on a ferrite toroid, connected in series with the winding of a cylindrical solenoid, coaxial with the axis of symmetry of the toroid, through which a direct magnetization current is passed. Due to the superposition of magnetic fields - circular and cylindrical - the so-called oblique magnetization of the toroid occurs. The angle φ is determined by the ratio of the magnetic field strengths of these types, for example, the ratio of the number of turns in these windings.

Depending on the inclusion of the circular winding on the toroid to the cylindrical winding around it, it is possible to change the slope of the magnetic field lines either to the right or left of the corresponding verticals, i.e., to form two types of ferromagnetic toroids with oblique magnetization. Moreover, if you create two permanent magnets with the same orientation of the magnetic lines of force of the oblique magnetization, and then turn one of these magnets 180 °, then these two magnets will repel each other when they approach each other along the axis of their symmetry (due to the property of magnetic repulsion of the same magnetic poles).

The aim of the invention is to measure the ratio of the vertical and horizontal components of the oblique magnetization in a pair of ferromagnetic toroids facing each other with the same magnetic poles, and their force action on each other when they approach each other.

This goal is achieved in the inventive device for measuring the force interaction of ferromagnetic toroids, consisting of a detachable cylindrical non-magnetic body, in the lower part of which is the first ferromagnetic toroid with a mechanism for its movement associated with the displacement sensor, and in the upper part is coaxially located the second ferromagnetic toroid, mechanically connected with a calibrated torsion-compression spring, the other end of which is fixed to the upper part of the cylindrical body, as well as with sensors the rotation angle of the axis to which the second ferromagnetic toroid is attached, the displacement sensors of the first and second ferromagnetic toroids and the rotation angle sensor of the axis of the second ferromagnetic toroid are connected to the first, second and third inputs of the computing and recording device by magnetizing the first and second ferromagnetic toroids so that the magnetization vectors emanating from the planes of the first and second ferromagnetic toroids facing each other are opposite to each other and tilted the vertical axis of symmetry, respectively, clockwise and counterclockwise.

Achieving the stated objective of the invention is explained by the arising compression force of a calibrated twisting-compression measuring spring by the vertical components of the oblique repulsive force when the first ferromagnetic toroid is supplied to the second. The displacement and rotation angle data from the known stiffness parameters of a calibrated torsion-compression measuring spring allow us to calculate the corresponding components of the magnetic field strengths obtained during oblique magnetization of a pair of ferromagnetic toroids, as well as the change in their values when the magnetic poles of the first and second ferromagnetic toroids come closer together, for which a computing and recording device is used, for example, based on a personal computer operating in accordance with favoring program.

The invention will be clear from the drawings.

Figure 1 shows the functional block diagram of the inventive device containing the following elements and blocks:

1 - lower cylindrical non-magnetic body;

2 - a rack with a stand;

3 - upper cylindrical non-magnetic body;

4 - plugs for fixing the halves of the body;

5 - the first ferromagnetic toroid with oblique magnetization;

6 - lower mounting cup (non-magnetic);

7 - feed axis of the lower mounting cup 6 (non-magnetic);

8 - second ferromagnetic toroid with oblique magnetization;

9 - upper mounting cup (non-magnetic);

10 - axis of rotation-sliding of the upper mounting glass (non-magnetic);

11 - bearing rotation-sliding axis 10;

12 - calibrated measuring spring twisting-compression;

13 - displacement sensor of the lower mounting glass 6;

14 - sensors of rotation and movement of the upper mounting glass 9;

15 is a computing and recording device.

Figure 2 presents the electric diagram of the oblique magnetization of a pair of ferromagnetic toroids, containing the following elements and blocks:

16 - coupled together a pair of ferromagnetic toroids (not magnetized);

17 - a circular winding wound on a pair of ferromagnetic toroids 16;

18 - cylindrical winding of the solenoid, coaxial to a pair of ferromagnetic toroids 16;

19 - storage high voltage capacitor;

20 - resistor current charge current;

21 - source of high voltage DC;

22 - high voltage arrester;

23 - power high-voltage diode.

Figure 3 presents the same diagram (figure 2) when viewed from the side on a pair of ferromagnetic toroids 16, which after magnetizing them with DC windings 17 and 18, which saturate the ferromagnet, become ferromagnetic toroids 5 and 8 (figure 1 ) with oblique magnetization.

Figure 4 shows the location of the magnetization vectors H _k and H _m for two points k and m located on the upper face of the toroid. Each of these vectors has a vertical H _⊥ and horizontal H _|| components (with respect to the plane of the end face of the toroid). Moreover, the vertical components H _⊥ for any points on a given toroid face are parallel to each other and with the axis of symmetry of the toroid z, and the horizontal components H _|| are located tangent to circles centered on the axis of symmetry of the toroid and drawn through any given point on the plane of the end face of the toroid. The tangent components form the y axis for the corresponding points on the end surface, and the x axis of such Cartesian coordinates are directed to the axis of symmetry of the toroid. The number of such coordinate systems is equal to the number of points at the end of the ferromagnetic toroid (theoretically, they are countless, but practically determined by the ratio of the area of the end of the toroid to the area of the magnetic domain).

Figure 5 shows two possible types of pairs of ferromagnetic toroids with oblique magnetization formed when replacing the inclusion of a circular coil 17 (figure 2) to a cylindrical coil of a solenoid 18 (by switching the start of H and the end K of circular winding 17).

Before considering the operation of the inventive device (Fig. 1), it is necessary to show how ferromagnetic toroids with oblique magnetization are created. The scheme of such magnetization of a pair of identical ferromagnetic toroids is shown in Fig.2 and Fig.3. The cylindrical winding of the solenoid 18 is capable of creating a vertically oriented magnetic field, and the circular winding 17, wound immediately on both ferromagnetic toroids, as shown in Fig. 3, magnetizes these toroids along their generators, that is, along circles circumferential to the axis of symmetry of the toroids located inside the body toroids. The superposition of these two magnetic fields creates oblique magnetization in the ferromagnetic toroids, as illustrated in FIG. 4 for two randomly taken points on the plane of their ends. Moreover, depending on the direction of the magnetizing direct current, for example, in a circular winding 17, oblique magnetization is possible of two types - with the inclination of the magnetization vector relative to the verticals to the right or left.

To create a unidirectional discharge current of the storage high-voltage capacitor 19 charged from the high-voltage direct current source 21 through the limiting resistor 20, a high-voltage diode 23 is used, connected in series with the storage high-voltage capacitor 19 and the high-voltage spark gap 22. There is no damped oscillation mode in such a circuit that would prevent the magnetization of ferromagnetic toroids. A unidirectional current pulse brings the ferromagnet of the toroids to deep saturation. This operation can be repeated, which ultimately leads to the magnetization of toroids.

After oblique magnetization of a pair of ferromagnetic toroids 5 and 8 (Fig. 1), one of them is turned 180 °, as a result of which we get a pair of mutually repelling vertically toroids, since they are facing each other with the same magnetic poles. So, the first and second pairs of ferromagnetic toroids have magnetic S-poles facing each other. In the first pair, the lower ferromagnetic toroid has a slope of the magnetization vector to the right of the vertical, and in the upper ferromagnetic toroid, on the contrary, the slope to the left of the vertical. In the second pair, these inclinations are opposite to those indicated above. When designating the directions of the magnetization vector for the end surfaces of the toroids facing each other in a given pair, up and to the right through the unit, and for directions down and to the left through zero, we obtain two pairs of ferromagnetic toroids with oblique magnetization, indicated in Fig. 5. The sum of the numbers for each of the pairs is equal to two, and the same components in the pairs should be different. Any other combinations should be excluded from consideration. There are four working combinations.

Now we turn to consideration of the operation of the claimed device (figure 1).

Ferromagnetic toroids with oblique magnetization are facing each other with the same North N-poles and belong to the second type of pairs (figure 5). The first ferromagnetic toroid 5 (lower) has the ability to move up and down relative to the second ferromagnetic toroid 8 (upper) and is considered to be stationary, mechanically connected with the displacement sensor 13. The second ferromagnetic toroid 8 (upper) has free vertical mobility and the rotation axis slip 10, which is mechanically connected with the displacement sensor and the angle sensor 14 of the axis 10. In addition, the indicated mobility of the second ferromagnetic toroid is limited by a calibrated measuring springs nd twisting compression 12, one end of which is fixed to the upper fitting sleeve 9 connected to the second ferromagnetic toroid 8 and slip-rotation axis 10, and the other end is fixed to the upper nonmagnetic cylindrical casing 3, secured to the lower mounting plugs 1 4.

Note that when the spring 12 is compressed, it also twists by a small angle, due to the inclination of the coil of the spring relative to a plane orthogonal to the axis of symmetry of the spring. This angle is monitored by the sensor 14.

When the first ferromagnetic toroid 5 is moved upward by Δz _1, an increase in the repulsive force between the first 5 and second 8 ferromagnetic toroids (due to the vertical components H _⊥ ) leads to a shift of the second ferromagnetic toroid upward by Δz ₂ <Δz ₁ . In this case, the compression of the spring 12 by Δz ₂ indicates the action of the compression force F _SJ = k ₁ Δz ₂ , where k ₁ is the known compression module for the spring 12. The compression force F _SJ is equal to the vertical component of the repulsive force F _⊥ . The indicated forces F _⊥ and F _|| , as you know, they change proportionally to the corresponding components H _⊥ and H _|| vectors of intensity H of the oblique magnetization of ferromagnetic toroids. Therefore, according to the measured values of the displacement Δz ₂ with the known modulus parameter k _1, one can judge the ratio of the components H _⊥ and Н _|| and thereby about the value of the angle of inclination φ of the vector H, as well as about the change in the magnitude of the forces F _⊥ and F _|| when the displacement Δz _{1 of the} first ferromagnetic toroid 5 is changed by the feed device of the lower mounting cup 6 through the feed axis 7, which is controlled by the displacement sensor 13. All data of the sensors 13 and 14 are transmitted to the computing and recording device 15, which operates according to a given program for calculating the quantities H _⊥ and Н _{| |} by the introduced parameter k ₁ and the variation of the displacement parameter Δz ₁ . As is known, the force F acting between the poles with magnetic fluxes Ф ₁ and Ф ₂ at a certain distance d = h / cosφ, where h is the distance between the ends of the toroids, is F = Ф ₁ Ф ₂ / 4πµ ₀ d ² = Ф ₁ Ф ₂ cos ² φ / 4πµ ₀ h ² . The magnetic fluxes Ф ₁ and Ф _{2 are} determined by the products of the inductions of the ferromagnetic toroids B = µ ₀ N and the area S of the ends of the ferromagnetic toroids, that is, Ф = µ ₀ НS [Вб], where µ ₀ = 1,256 * 10 ^-6 GN / m is the absolute magnetic vacuum permeability, N — magnetic field strength at the ends of the magnets [A / m], sizes S and h in [m ² ] and [m], respectively. The force F decomposes into components F _⊥ and F _|| calculated as F _⊥ = Fcosφ and F _|| = Fsinφ, where the angle φ = arctan (H _|| / H _⊥ ). It can be seen that with decreasing distance h between the ends of the ferromagnetic toroids, the force F of the oblique repulsion increases quadratically, which tends to compress the calibrated measuring spring 12. The distance h is achieved by the corresponding controlled feed Δz ₁ .

It should be mentioned that in the absence of magnetization of ferromagnetic toroids 5 and 8 under the weight of the ferromagnetic toroid 8, its upper fixing sleeve 9 and the slip-rotation axis 10 and the other attached thereto mass calibrated measuring spring is stretched by an amount Δz ₀ = -k ₁ P _Σ , where P _∑ is the total weight of the moving part of the device, therefore, during the initial adjustment of the device, the ferromagnetic toroid 5 with oblique magnetization should be moved to the second toroid 8 so that the repulsive force of these toroids equal each other whatever weight P _∑ , while the measuring spring 12 would be unstretched and not compressed (its compression in the initial state Δz ₀₂ = 0).

The calculation program is somewhat complicated by the fact that the modulus k ₁ , strictly speaking, does not remain constant, since the twisting of the spring 12 changes the elastic modulus k ₁ . In fairly rough estimates, however, one can assume that the value of this module is constant and known (experimentally determined).

The technical solution can be used to verify the identity of pairs of ferromagnetic toroids with oblique magnetization, to cull them and to test the toroids for their force interaction, in particular, to experimentally determine the most advantageous tilt angles φ of the tension vector H relative to the vertical.

Information sources

1. Preobrazhensky AA, Bishird EG, Magnetic materials and elements, 3rd ed., M., 1986.

2. Fevraleva IE, Magnetosolid materials and permanent magnets, K., 1969.

3. Permanent magnets. Handbook, M., 1971.

Claims (1)

A device for measuring the force interaction of ferromagnetic toroids, consisting of a detachable cylindrical non-magnetic body, in the lower part of which there is a first ferromagnetic toroid with a mechanism for its movement associated with the displacement sensor, and in the upper part is located coaxially the second ferromagnetic toroid mechanically connected with a calibrated torsion spring - compression, the other end of which is fixed with the upper part of the cylindrical body, as well as with displacement sensors and the angle of rotation of the axis to which is attached The second ferromagnetic toroid, the displacement sensors of the first and second ferromagnetic toroids and the angle sensor of the axis of the second ferromagnetic toroid are connected by outputs to the first, second and third inputs of the computing and recording device, and the first and second ferromagnetic toroids are magnetized so that the magnetization vectors coming from the planes of the first and second ferromagnetic toroids facing each other, are opposite to each other and are inclined relative to the vertical axis of their symmetry ns, respectively, clockwise and counterclockwise.

Images