SU1410114A1 - Magnetizing apparatus - Google Patents

Abstract

The invention relates to electrical engineering and is intended to magnetize permanent magnets. The purpose of the invention is to increase the magnetization efficiency, simplify and reduce the size of the device. This goal is achieved due to the fact that a device containing a three-phase rectifier 2 supplied from a three-phase voltage source 1, equipped with a three-phase thyristor group 3, which serves as a control key, whose output is connected to an electromagnet and a block of charging capacitors, additionally introduced three diodes 9, 10, 11, the electromagnet and the block of charge capacitors are made respectively with two coils 4, 5 and in the form of two groups of capacitors 6, 7, connected according to the four-shoulder bridge scheme, two opposite arms and which are formed by electromagnet coils, and the other two protrusions, their arms, are groups of capacitors, and diode 9 is installed in the diagonal of the indicated bridge in a direction that is not conductive for groups of capacitors, electromagnet coils 4, 5 are connected according to each other, and capacitors 6, 7 are shunted by reverse diodes 10, 11, and a four-arm bridge can be included in the diagonal of a four-arm bridge. 12 1 h. item f-ly, 2 ill. iS (L

Description

fig1

The invention relates to electrical engineering, in particular, devices for magnetizing permanent magnets and ferromagnetic products, and can be used in mechanical engineering and instrument engineering.

The purpose of the invention is to increase the efficiency of magnetization, uniformity and the reduction of device dimensions.

FIG. 1 is a schematic diagram of the device; in fig. 2 is an oscillogram of the change in current i in the coils of an electromagnet as a function of time t.

The device includes a three-phase voltage source 1, a three-phase bridge rectifier 2, equipped with a three-phase thyristor group 3, which serves as a control key. An electromagnet for magnetizing and a block of charge capacitors are connected to the output of the bridge external motor 2. The electromagnet is made with two identical coils 4 and 5, connected according to each other, and a block of capacitors - in the form of two identical groups of capacitors 6 and 7. Coils 4 and 5 and groups of capacitors 6 and 7 are connected together according to the four-shoulder circuit bridge 8, the two opposite arms of which are formed by electromagnet coils 4 and 5, and the other two opposite arms are formed by groups of capacitors 6 and 7. In the diagonal of the four-shoulder bridge 8, a diode 9 is installed in a non-conductor for groups of capacitors 6 and 7 of the direction. Accordingly, the groups of capacitors 6 and 7 are connected by reverse diodes 10 and 11. In series with diode 9, an adjustable resistor 12 can be inserted into the diagonal of bridge 8. The key, which is a three-phase group of thyristors 3, is controlled from For example, in the form of a transformer with a rectifier in the secondary winding and a control pulse equipped with a delay node, for example, in the form of a time relay.

The device works as follows.

When a control pulse is applied from the control unit 13 to the three-phase group of thyristors 3, which serves as a control key, they are opened and a full voltage applied from each three-coil 4 and 5 of the electromagnet is applied from the three-phase bridge 2. At this moment the coils 4 and 5 are relative to each other, connected in parallel and the current flowing through them is determined by the charging current, respectively, of the groups of capacitors 7 and 6. At first, the current in coils 4 and 5 smoothly increases from zero to some maximum value, and then as it charges For groups of capacitors b and 7, it gradually decreases, which corresponds to the change in current in the o-a-b curve (Fig. 2). Similar to the change in current in coils 4 and 5

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There is a change in the magnetic flux acting on the magnetized magnet or product. Due to the inclusion of diode 9 in the non-conductive direction for groups of capacitors 6 and 7, they cannot be charged through the diagonal of the four-arm bridge 8. When the groups of electrical consoles b and 7 are charged to half the voltage supplied from the three-phase bridge 2, their charging stops. From now on, determined by point b in FIG. 2, the current-free diode 9 opens, and the coils 4 and 5 are powered through a diagonal four-arm bridge 8, namely, through diode 9 and an adjustable resistor 12. In this case, the coils 4 and 5 of the electromagnet are connected in series with respect to each other and flowing in them, the current remains unchanged in magnitude, which characterizes the steady state current and magnetic flux acting on the magnetized magnet or product. The latter provides the final promagnetisation of the magnet or product and corresponds to the straight line section b-in the curve (Fig. 2). The duration of the steady-state current and magnetic flux in the coils 4 and 5 of the electromagnet is controlled by the control unit 13. When the control pulse is switched off, the thyristors of the three-phase group 3 are closed, as they are connected to the AC circuit, where the voltage between their anodes and cathodes periodically reaches zero. After closing the thyristors of the three phase group 3, which is characterized by a dot in the curve of FIG. 2, the groups of capacitors B and 7, charged to half the voltage, begin to slowly discharge to zero, respectively, through the coils 4 and 5 of the electromagnet and the diagonal of the four-arm bridge 8, in particular through diode 9 and the adjustable resistor 12. In this case, in comparison with the established the current mode in the coils 4 and 5 does not change its direction, and the magnetic flux acting on the magnetized magnet or the product, like a current, slowly drops to zero, which corresponds to the portion of the i-d curve (Fig. 2). Aperiodic discharge of groups of capacitors b and 7 onto coils 4 and 5 is achieved by tinting groups of capacitors b and 7, respectively, by reverse diodes 10 and 11. Thanks to the willing inclusion of coils 4 and 5 of an electromagnet, its resulting magnetic flux acting on the entire pulse to be magnetized a magnet or a product is a double magnetic flux created by each of the coils 4 and 5. The process and the end of the magnetization of the permanent magnet or product can be controlled with the help of ikatora, e.g. voltmeter 14.

A steady increase achieved in the device, a steady state and a smooth and slow decrease in the magnetic flux acting with a low speed gauge, which serves as a control key, are connected to the rectifier output an electromagnet and a charging capacitor unit, characterized in that

magnetisation magnet or magnetization product efficiency,. This determines a significant decrease in the current induced by it in the magnetic circuit of the electromagnet and in the constant magnet itself (especially metal fluxes, for example, such as UNDK) or a ferromagnetic electrically conductive product. The latter causes a decrease in the intrinsic magnetic flux created by the indicated current, which counteracts the magnetization flux, which leads to a significant decrease in its magnetic flux.

and reduce the size of the device, it is equipped with diodes, the electromagnet is made with two coils, and the charging capacitor unit - in the form of two groups of capacitors, while the electromagnet coils and the charging capacitor unit are connected according to the four-shoulder bridge circuit, the two opposite arms of which are formed by electromagnet coils, and the other two opposite shoulders - in groups

the demagnetizing effect on the constant 5 capacitors, and in the diagonal is a magnet or a product. This makes it possible to significantly increase the magnetization efficiency of permanent magnets and products,

Claims (2)

Invention Formula . A magnetizing device containing a three-phase bridge rectifier supplied from a three-phase voltage source, equipped with a three-phase group of a tyrising bridge, a diode is installed in a direction that is nonconducting for groups of capacitors, electromagnet wc drives are tychhene in relation to each other, and the groups of capacitors are reverse-clamped diodes. 2. A device according to claim 1, characterized in that an adjustable resistor is connected in series with the diode of the four-arm bridge in series with the diode. 7. An electric switch and a charge capacitor unit are connected to the output of the rectifier, characterized in that, in order to increase the power of magnetization efficiency,. and reduce the size of the device, it is equipped with diodes, the electromagnet is made with two coils, and the charging capacitor unit - in the form of two groups of capacitors, while the electromagnet coils and the charging capacitor unit are connected according to the four-shoulder bridge circuit, the two opposite arms of which are formed by electromagnet coils, and the other two opposite shoulders - in groups The tied bridge is installed in a non-conductive diode for the groups of capacitors, the electromagnet coils of the VC are tyuchen according to each other, and the groups of capacitors are terminated by reverse diodes. 2. A device according to claim 1, characterized in that an adjustable resistor is connected in series with the diode of the four-arm bridge in series with the diode.