SU660728A1 - Method of exciting oscillation of electromagnetic vibration drive - Google Patents

Description

I

The invention relates to a vibration technique, and more specifically to the excitation of vibration mechanical oscillatory systems with electromagnetic vibration exciters operating in near-resonant mode.

A known method of exciting oscillations of an electromagnetic vibratory drive is that a one-half-period voltage generated by a half-wave rectifier is applied to the coil of the electromagnet of the exciter 1.

However, the known excitation method has a low efficiency of the vibrating drive.

The closest to the invention in technical essence and the achieved result is a method of exciting oscillations of an electromagnetic vibration drive, consisting in forming a sequence of pulses in the form of a half-wave voltage and applying it to the electromagnet winding of the vibration drive 2. But this method does not provide a high efficiency of the vibration drive.

The purpose of the invention is to increase the efficiency.

This goal is achieved by the fact that, in the excitation method, the pulse duration is set within 0.33-0.83 from the half-cycle duration, while the amplitude of the pulses is increased relative to the maximum allowable one-half-wired winding voltage e, of the solenoid magnet in the number K defined according to the formula

- D.2 (Ki / T)

where TC is the pulse duration;

T is the half-period voltage duration.

This formula is approximate and makes it possible to calculate the number K with an accuracy of 200/0.

The method is carried out as follows.

Claims (2)

During the formation of an impulse impulse in the form of single-wave voltage, the duration of these pulses is set within 0.33 --- 0.83 of the length of the half-period, while% 1 simultaneously increases the amplitude of the pulses by K times from the maximum permissible for single-wave power . The pulses generated in this way are fed to the input of the electromagnet winding of the vibrodrive. The introduction of new operations allows to reduce the duration of the current flowing through the electromagnet winding, which allows to obtain the maximum oscillation amplitude of the vibrating drive at a lower value of the current flowing through the electromagnet winding, and therefore increase efficiency. This is due to the fact that the active-inductive nature of the load, which is the vibro-drive, with the usual single-half-power supply at the maximum amplitude of vibration of the vibro-drive, the duration of the current in the coil of the electromagnet of the exciter is more than half the voltage period of the power supply. And since the force developed by an electromagnet is proportional to the square of the current and has a duration equal to the duration of the current, the force acting in a time interval longer than half the period slows down, rather than swaying, the vibrodrive. By reducing the duration of the pulses and increasing its amplitude, it can be achieved that all the energy enclosed in them will be directed only at the swing of the vibrating drive, since there will be no excitation pulses in negative half-periods. The pulse amplitude can be increased but compared to the limiting one for the case of full-wave excitation. The use of the method allows to increase the efficiency of existing electro-magnetic vibration drives, for example, with thyristor control (saving energy), to create new electromagnetic vibration drives of higher performance with the same power consumption and to simplify the calculation of electromagnets of the vibration exciter. On the basis of theoretical and experimental studies, the dependence of the ratio of power consumed by an electromagnet exciter in the considered method to the power consumed by a known method on the thyristor unlocking angle, i.e., the pulse duration for the maximum amplitude of vibration of the vibrator, which is represented as empirical formulas for the range of Po /, i where - the unlocking angle of the thyristor in degrees; PO is the power consumed by an electromagnet with a known excitation method, i.e. at y (diode mode), half-wave voltage; Р - power consumed by an electromagnet for 30 ° 120 °; - relative power consumption ratio. From the formula, it can be seen that with an increase in the unlocking angle of the thyristor (a decrease in the pulse duration), the power consumed by the electromagnet decreases to obtain the same oscillation amplitude of the vibration drive, and this indicates an increase in efficiency. Claims The method of exciting oscillations of an electromagnetic vibrodrive, which consists in forming a sequence of pulses in the form of a half-wave voltage and applying it to the coil of an electromagnet of the vibrodrive, characterized in that, in order to increase the efficiency, the duration of the pulses is set to 0.33-0.83 from the duration of the half period, while the amplitude of the pulses is increased with respect to the limit permissible half-time voltage of the winding of the electromagnet to K, determined by the formula, d.2 / -G.UT) 3 L, g (where f is the pulse duration; P is the voltage half-period duration. Sources of information taken into account during the examination 1. Means of automation of production processes in Chemical Industry. Proceedings of the Moscow Chemical and Technological Institute, IM DI Mendeleev, Issue 77, M., 1973, pp. 71. 2. USSR author's certificate number 481885 cl. G 05 D 15/01, 1975.