RU2796771C2 - Method of obtaining pulsed alternating magnetic fields of varying intensity for controlled magnetotherapy - Google Patents

Abstract

FIELD: medical equipment.

SUBSTANCE: method of obtaining pulsed alternating magnetic fields with a uniform induction density in the impact zone for conducting controlled magnetotherapy procedures and a device for its implementation are proposed. The invention relates to a method of obtaining pulsed alternating magnetic fields of varying intensity for magnetic therapy. The method involves the use of magnets of a special shape mounted on a rotation platter as a set in cartridges. Permanent magnets in cartridges are placed in cartridges at intervals of free sectors, alternating poles. The law of changing the area of the magnets in the radial direction determines the shape of the permanent magnets and allows to equalize or set the density of the magnetic field in the area of the magnets for any speed of rotation of the support disk. The magnets have a shape similar to a truncated sector limited by external and internal arcs, and instead of segments of radii — by symmetrical segments of hyperbolas, while the ratio of the length of the external arc to the length of the internal arc is inversely proportional to the ratio of the radii of the external and internal arcs. Using the proposed method allows to apply it to a wide range of diseases, individualize the treatment by magnetic therapy methods and carry it out remotely.

EFFECT: significant reduction of the risk of infection in patients during pandemics, if it is required to undergo magnetic therapy procedures.

9 cl, 3 dwg

Description

The invention relates to the field of magnetotherapy, otherwise called electrodeless electrotherapy, carried out by creating pulsed alternating magnetic fields with mechanically driven permanent magnets, which corresponds to the IPC qualification as amended in 2020 as A61N 2/12.

At the time of filing this application, both various methods and various devices for generating pulsed alternating magnetic fields were known. During a patent search in the indicated heading, the following analogues of the present invention were found:

– application for invention RU 2007117446 A;

– utility model patent RU 101929 U1;

– application for invention RU 2009101814 A;

– patent application WO2010067180;

– patent application WO2019164903.

In addition to the above applications and patents, the basis for this invention was also the invention according to patent RU 2632443, relating directly to the cure of a specific disease by magnetic therapy.

To obtain a positive effect of curing the disease according to patent RU 2632443, the applied technique involves a consistent increase in the strength of the magnetic field used and the time of its exposure from session to session.

According to the patent application WO2019164903, there are sufficient grounds to believe that the methods of treating other diseases using magnetotherapy with pulsed magnetic fields will also have specific requirements for the strength of the magnetic fields used, their configuration, pulse frequency and exposure time.

The implementation of such requirements according to the patent application RU 2007117446 A seems to be quite difficult, since the proposed solution has a relatively complex electromechanical design. In exactly the same way, the solution according to the utility model patent RU 101929 U1 is also a very complex mechanical structure.

Patent application WO2010067180 relates to a stationary device using magnetic field concentrators, which complicates the design and its implementation in a compact design is not possible.

In contrast to the methods of influence according to patent application WO2019164903, the electric field in the patient's body according to the proposed method arises by itself due to the operation of Faraday's law, which greatly simplifies its implementation.

In order to eliminate these shortcomings and achieve accurate dosed effects of a pulsed alternating magnetic field of varying intensity, as well as for the purpose of carrying out individualized programmable magnetotherapy procedures, the following solutions are proposed below.

As the main prototype, the application for the invention RU 2009101814 A was chosen, relating to a portable device for conducting magnetotherapy sessions and coinciding in the maximum number of features, but having a significant drawback - the uneven distribution of the magnetic flux density in the radial direction, created by rotating magnets of the claimed shape.

As follows from the claims of the application for invention RU 2009101814 A:

"1. A portable device for generating an alternating magnetic field for treatment with a magnetic field, comprising

a) at least two permanent magnets (5) having the shape of a circular or annular sector, located on a circular base (3) in its circumferential direction and evenly distributed over it, and ...

d) between two permanent magnets (5) located in the circumferential direction next to each other, in each case, an unoccupied free segment (5a) is provided, having approximately the same shape of a circular or annular sector as the permanent magnets (5).

When using such a method for obtaining a pulsed magnetic field, it is impossible to create a field with a uniform distribution of magnetic induction in the area of action of the magnets of the aforementioned shape.

It is known that the induction emf ε is the derivative of the change in the magnetic flux Φ over time.

In turn, the magnetic flux Φ is equal to the scalar product

where B is the magnetic field induction;

S is the surface area penetrated by the magnetic flux;

α is the angle between the magnetic induction vector and the normal to the plane S.

In the case under consideration, when the direction (vector) of the magnetic field coincides with the normal (perpendicular) to the surface S, the angle α is 0 degrees and
cosα = 1.

Thus, expression (1) can be replaced by a simplified expression

where d S is an element of the area of the magnet or under the magnet at a distance R from the center of rotation, since only the relative speed of movement of the magnet and the surface is important for the induced EMF.

It follows from expression (3) that for a system with rotating magnets, the induced EMF depends both on the surface area penetrated by the magnetic field of the magnet surface element d S and on the linear velocity of this magnet element.

The linear speed of the point of the circle V (an element of the surface of the magnet d S) is determined by the expression

where R is the radius of removal from the center of rotation;

f is the rotation frequency.

those. the linear speed of rotation increases with distance from the center of the disk of rotation in proportion to the radius of removal.

Thus, due to the fact that the magnets in the prototype have the declared shape of sectors or truncated sectors, in which the area of the element d S increases with distance from the center of rotation, the result is a certain quadratic dependence of the distribution of the magnetic flux density and the induced EMF on the radius of removal from the center of the platter of rotation.

Therefore, with the claimed shape of the magnets, it is impossible to achieve a uniform effect of magnetic field pulses on human tissues in the area of the magnets.

To eliminate this drawback, it is proposed to change the shape of the magnets used according to the application for invention RU 2009101814 A in the form of circular or truncated sectors (Fig. 1) so that they look like a truncated sector, which is limited by external and internal arcs, and instead of segments of radii - symmetrical segments of hyperbolas, while the ratio of the length of the outer arc to the length of the inner arc is inversely proportional to the ratio of the radii of the outer and inner arcs (Fig. 2). Moreover, the ratio of the lengths of the generating arcs that limit the magnets must correspond to the proportion

where L _R is the length of the arc of a circle of outer radius R, bounding the ring of the disk of revolution;

L _r is the length of the arc of a circle of inner radius r, bounding the ring of the disk of revolution.

In this case, the ratio

In this case, when using magnets of the claimed form, the same effect of magnetic field pulses on human tissues in the area of the magnets is achieved, because the elementary area of the magnet d S decreases as the radius increases, thereby compensating for the increase in linear velocity with an increase in the radius of removal from the center of the support disk of rotation.

Precise regulation of the force of influence according to the proposed method of magnetotherapy is possible in three ways:

- the 1st method involves changing the duty cycle of the magnetic field pulses by changing the ratio of the internal arcs of the magnets and sectors of non-magnetic materials installed in the cartridges;

- according to the 2nd method, the adjustment is carried out by installing a pair of magnets in the cartridges (N ≥ 2 * n, where n are the numbers of the natural series) with different values of residual induction;

- according to the 3rd method, the adjustment of the force of influence is carried out by changing and / or maintaining at a given value the speed of rotation of the support disk with pre-installed magnets of the claimed shape and the possibility of replacing them with others having different values of residual magnetic induction.

To implement the first and second methods, the aforementioned magnets of the claimed form are installed in replaceable cartridges in such a way that the polarity of the poles of the magnets alternates. In turn, the magnets in the cartridges alternate with sectors of non-magnetic materials.

To obtain the duty cycle of the magnetic field pulses Q equal to 2, the lengths of the internal arcs of the magnets are equal to the lengths of the internal arcs of sectors made of non-magnetic materials (Fig. 2):

where L _s is the length of the inner arc of a sector made of non-magnetic material;

L _r is the length of the inner arc of the magnet.

To obtain other values of the duty cycle of the pulses Q the ratio is maintained

The rotation speed of the platter is controlled by an electronic control unit (Fig. 3), which includes:

– brushless DC motor;

– brushless motor controller controlled by frequency;

– voltage controlled clock generator (VCO);

– a control microcontroller with a digital-to-analog converter (DAC) and an interval timer (IT);

– Hall sensor for feedback;

- microchips of the controller for communication with Wi-Fi networks.

The accuracy of the impact force of the pulsed magnetic field in this case depends on the rotation speed of the support disk, and it depends on the frequency of the VCO, the frequency of the VCO clock pulses depends on the DAC capacity of the control microcontroller used; exposure time and its accuracy - on the IT bit depth and the repetition rate of the counting pulses received from the Hall sensor. With the technical implementation components used, the DAC bit depth was 1024, switching between 2 generators doubled this value up to 2048. Together with the use of cartridges carrying a different number of magnets with different residual induction values ranging from 100 μT to 1200 mT, the number of possible options exposure to a magnetic field exceeds 500,000.

The digit capacity of the IT used was 14 with a repetition rate of counting pulses of 4 ms, which made it possible to obtain a large range of exposure time with high accuracy. This made it possible to vary the intensity and duration of magnetic therapy procedures, choosing the most appropriate values for a given organ or disease.

The control unit also provides the ability to set certain sequences of rotation speeds during a session of controlled magnetotherapy by remotely loading new values of the DAC register and programmable outputs of the control microcontroller that act on the VCO, which expands the functionality of the proposed method.

In addition to the hardware, when implementing the method obtaining pulsed alternating magnetic fields of varying intensity for controlled magnetotherapy it is possible to use the corresponding software hosted both on a separate smartphone and on a remote server. Such a solution in a hospital environment will allow medical staff to individualize treatment for each patient, choosing approved treatment parameters recommended by appropriate methods, as well as increase the load on existing equipment.

Replaceable cartridges allow you to automatically maintain the recommended exposure parameters for a specific disease in offline mode, and in remote control mode - to adjust the exposure strength and duration of magnetotherapy procedures within certain limits. Identification of installed cartridges with magnets prevents unwanted usage patterns by locking them out. Information on the cartridges is reflected by the display both directly on the device that implements this method, and on the user's smartphone and/or on the display of a remote server.

The use of the proposed method at home in a pandemic will avoid unwanted personal contacts and reduce the number of patient visits to medical institutions, and the attending physician will be able to remotely adjust the treatment.

Taken together, the proposed method for obtaining pulsed variable magnetic fields of varying intensity for controlled magnetotherapy has a number of advantages:

- expands the functionality of this method of treatment;

- allows you to significantly improve the quality of treatment due to its individualization;

– reduces the cost of treatment;

- significantly reduces the number of visits by patients to medical institutions, which is important in the context of epidemics and pandemics.

Claims (10)

1. A method for obtaining pulsed alternating magnetic fields of varying intensity for magnetotherapy, carried out by installing permanent magnets on the support disk of rotation with a shape similar to a truncated sector, which is limited by external and internal arcs, and instead of segments of radii - by symmetrical segments of hyperbolas, with In this case, the ratio of the length of the outer arc to the length of the inner arc is inversely proportional to the ratio of the radii of the outer and inner arcs, and the magnets are installed in replaceable cartridges in such a way that the polarity of the magnet poles alternates, while the magnets in the cartridges alternate with sectors of non-magnetic materials, and the number of magnets installed in the cartridges equal or more magnets and a multiple of 2. 2. The method according to claim 1, characterized in that to obtain different values of the duty cycle of the magnetic field pulses, the lengths of the internal arcs of the magnets differ from the lengths of the internal arcs of the sectors of non-magnetic materials. 3. The method according to claim 1 to obtain a duty cycle value of 2, the lengths of the internal arcs of the magnets are equal to the lengths of the internal arcs of the sectors of non-magnetic materials. 4. The method according to claims 1-3, characterized in that to vary the impact force, the residual induction of the magnets in the cartridges is in the range from 100 μT to 1200 mT, while the values of the residual induction of the magnets in one cartridge are equal or differ from each other. 5. The method according to claims 1 to 4, characterized in that in order to obtain a non-zero resulting action of positive and negative field pulses, the angle between the axes of the magnets differs from 180°. 6. The method according to claims 1-5, characterized in that the frequency of the magnetic field pulses is set by changing cartridges with a different number of magnets. 7. The method according to claims 1-6, characterized in that the frequency of the magnetic field pulses is set by changing the speed of rotation of the support disk and lies in the range from 1 to 100 Hz. 8. The method according to claims 1-7, characterized in that the time of exposure to a pulsed magnetic field is set by a hardware or software interval timer. 9. The method according to claims 1 to 8, characterized in that the frequency of the magnetic field pulses and the time of its exposure are programmed remotely using connections to Wi-Fi networks to download treatment session data. 10. The method according to claims 1-9, characterized in that during the session of the magnetotherapy procedure, the frequency of the magnetic field pulses and the time of its exposure to these parameters change according to a given law.

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