SU67361A1 - Ignaytron ignition device - Google Patents

Description

The object of the present invention is an ignition device ignitor used for short-term supply of electric current to a load, for example, for short-term supply of current to the welding electrodes of spot welders from an AC source.

In such devices, it is already known to use an auxiliary (thyratron, connected by the anode through the limiting resistance to the anode of the ignitertron, and by the cathode to the ignition electrode of the latter, and ignited, in turn, by voltage pulses from the pulse transformer arriving at its grid.

A distinctive feature of the proposed device is that, in order to ignite the ignaytron only for the duration of one half-cycle of alternating current, a capacitor is charged in the circuit of the thyratron grid in series with the secondary winding of the pulse transformer, which is negatively charged relative to the grid by the first voltage pulse on the load valve or auxiliary transformer.

Diagrams of two possible variants of the proposed device are shown in FIG. I, 3, and explanatory graphs are shown in FIG. 2 drawings.

FIG. 1 shows a diagram of the first embodiment of the device in which the capacitor 5 is charged with the aid of the auxiliary valve 8. Here the pulsed power supply of the load 4 from the AC mains connected to the terminals c and d is carried out at the moments of ignition 5 ignited with the help of the auxiliary thyratron 1, connected through the limiting resistance 10 parallel to the gap, the anode is the ignition electrode of the igniter, when the button is pressed.

If the button is not pressed, then electrical processes occur only in the grid circuit of the thyratron 1. The anode current of the thyratron /, as can be seen in FIG. 2, does not leak by; The positive values of the voltages on the anode and on the grid are not simultaneous.

When the button is connected, the points b are connected to the scheme f, and the adventure of the thyratron to ignaytron occurs. The first positive peak voltage

on the grid of the thyratron / on the side of the peak transformer 2, included in the secondary winding of the glow transformer 7, unlocks the thyratron, and the igniter 3 is ignited. On the load 4, the entire voltage of the supply network drops, which leads to the appearance of current in the circuit of conductors k, b, f, g, d (marked by the dotted line in Fig. 1). In this case, the capacitor 5 is charged up to a voltage of approximately equal to the maximum voltage of the supply network of the network, and since its facing is negatively connected to the grid of the thyratron J, the latter is locked until the voltage of the capacitor 5 is self-discharged the latter is not reduced to a value at which the thyratron 1 is again heated. From this point on, the switching processes are repeated automatically. However, since the welder presses the button for a period not exceeding 1 second, automatic unlocking of the circuit is not observed, for they occur (with the button pressed) after incomparably longer periods of time.

The electrical processes occurring in the circuit are depicted in FIG. 2. Here we have the following notation:

and, -, - is the supply voltage, f / of is the voltage on the anode of the thyratron /, U // i is the voltage on the capacitor 5, U, f is the voltage on the grid of the thyratron.

FIG. .3 is a diagram of a variant of the device with capacitor 5 charging through an auxiliary transformer 9. i

When the control button is not pressed, the secondary winding of the transformer 9 has a very small resistance to the impulses of the grid current of the thyratron 7, since the primary winding of this transformer is shunted by the load resistance 4. Therefore, the grid, voltage and voltage curves on the capacitor 5 differ little from those shown in FIG. 2

When the control button is pushed up (above) as a result of igniting the igniter 3, the voltage on the load 4 is transformed by the transformer 9. The voltage of its secondary winding causes a current in the circuit marked in FIG. 3 dotted line. As a result of the flow of current. the capacitor 5 is charged up to a voltage that is almost equal to the maximum voltage on the secondary winding of the transformer 9 (which should be much greater than the voltage on the capacitor 5 with the control button not pressed).

Since the negative plate of the capacitor 5 is connected to the grid of the thyratron I, the latter, as in the first variant of the circuit, turns out to be locked for a long period of time.

Subject invention

A device for igniting the igniter, connected to the load supply circuit from an alternating current with the help of a thyratron connected by the anode through the limiting resistance to the anode of the ignition neutron, and the cathode to the igniting electrode of the latter, and the receiver, in turn, received by voltage pulses from its source impulse transformer, differing from the fact that, in order to ignite an ignaytron only for the time of one half period of alternating current, into the circuit of the thyratron grid in series with the secondary winding of the impulse transformer The capacitor is connected to the mator and is charged negatively with respect to the grid by the first impulse, either on the load or by means of either an auxiliary valve or an auxiliary transformer.

The button is pressed.

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