SU44096A1 - Device for reducing the demagnetization of permanent magnets in magneto-type devices - Google Patents

Description

When devices of the magnet type are used, the permanent magnet used in them is subjected to a strong demagnetizing effect of the current arising from the short circuit of the primary winding of the core.

This demagnetizing effect is particularly evident in the so-called transient short circuit of the primary winding. In fact, the magneto workflow is also composed of a periodic series of non-stationary short circuits, but at the same time the current is opened before the measles takes a position in which the demagnetizing effect is clearly visible (besides the current does not reach its maximum value). In a transient short circuit, the primary winding remains closed for a long period of time. In this case, the anchor consistently occupies all positions and the demagnetizing effect of the primary current becomes especially significant.

This forces the use of magnets with an increased coercivity value, since a non-stationary short circuit occurs almost every time the magneto is turned off (i.e., a primary circuit is shorted with a special switch in addition to the interrupter).

The present invention relates to a device for the purpose of reducing the demagnetization of permanent magnets resulting from the reaction of the core and increasing their use of energy in magneto-type devices.

The said device, shown schematically in the drawing, is carried out by applying a short-circuited damping winding, made in the form of a copper cup, put on a permanent magnet in a part of it. Such a winding is intended to reduce the demagnetization of the magnet and maintain the flow constant in it in all cases where the magnet is used to induce currents in any circuit.

The annular permanent magnet 2 rotates about an axis perpendicular to the plane of the drawing, resulting in changes in the magnetic flux in the stationary core 3. These changes are used by means of windings in the usual magneto way.

The purpose of the proposed winding /, as already noted above, is to maintain the constant magnetic flux constant of the magnet, despite the demagnetizing effect of the core 3 winding reaction.

The action of the winding is similar to the action of the damper system of synchronous machines. With all the fluctuations of the magnet flux in the proposed winding will be

induce an electric current that tends to keep the magnetic flux of the magnet constant. As a consequence, such a winding will not only reduce the demagnetization of the permanent magnet, but also improve the magneto operation by increasing the current in the primary winding. Additional losses in the winding / are compensated by a decrease in the ripple flux of the permanent magnet and, most importantly, by a significant increase in the energy stored in the winding of the core (like the influence of the damper winding of synchronous machines).

The application of the proposed winding is particularly effective in the so-called

magnets, in which a particularly strong demagnetization of the ends of the magnet is observed.

The subject matter of the invention.

A device for reducing the demagnetization of permanent magnets in devices of the magneto type, arising due to a core reaction, characterized in that a permanent magnet designed to induce current in any circuits, or a short-circuited damping winding, is used on it, for example, honey cups.