CS205702B1 - Connection of the electric circuit of the electromagnetic automatic valve - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a circuit for a solenoid actuating a solenoid valve used, for example, as a safety valve in a heating oil burner circuit. mazut.

DC solenoid circuits that suitably adjust the waveforms of current or voltage in the winding to affect armature movement typically utilize a transient action of the electromagnet circuit after the winding is connected to a power source to accelerate or slow the armature movement. The application of these circuits to the self-acting traction solenoid, where the armature movement is often slow due to the high oil viscosity, is difficult because the duration of the electrical transition process is considerably shorter than the armature movement time. Hitherto known circuits usually contain larger capacitors which reduce the long-term reliability and lifetime of the device or require either a separate magnetic auxiliary circuit or multiple winding outlets, which complicates and increases the cost of producing these electromagnets. In automatic valves, several times less force is required to maintain the valve closure in the open position when the magnet winding is connected to a voltage source than when opening, which means less winding power. The use of an automatic safety valve, which is practically permanently open, minimizes the use of the electrical energy supplied to the windings. This is particularly detrimental to the operation of the solenoid valves at higher pressures or larger flow rates.

Connection of the solenoid valve winding to the collector - emitter transistor path is also known.

Their disadvantage is that the current required to open the valve still flows through the transistor and the winding, even if the current is considerably smaller to keep it open.

The above-mentioned drawbacks are eliminated by the connection of the electric circuit of the transistor solenoid valve according to the invention. It is based on the fact that a posistor is connected between one source terminal and the base of the transistor.

The advantage of connecting the electric circuit of the solenoid valve is, first of all, to reduce the power consumption, increase the reliability and durability and simplify the apparatus with this electric circuit according to the invention. ''

A specific example of the electrical circuit of an automatic valve solenoid according to the invention is shown in the drawing.

The winding 1 of the valve solenoid circuit is connected beginning to the first voltage source terminal 2 and ending to the collector 3 of transistor 9. The emitter 4 of transistor 9 is connected to the second voltage source terminal 5. A resistor 6 is connected between the base 7 of transistor 9 and the first terminal 2. A reset diode 8 is connected between the collector 3 of the transistor 9 and the first terminal 2. 9.

When the electrical circuit is connected to a voltage source, electrical current passes through the resistor B and since the beginning of the resistor 6 has a low temperature and therefore a minimum resistance, this current is maximum. The current through the resistor 6 is simultaneously the maximum current of the base 7 and the transistor 9 is open. The whole voltage of the power supply is practically on the winding 1. In this state, the electromagnet has the maximum power, and thus the power, and opens the valve. The electric current passing through the resistor 6 will gradually warm it up and its resistance value will increase significantly after the switching temperature has passed. This reduces the base current of transistor 9 and the current across the transistor

Claims (1)

'SUBJECT Connection of the electric circuit of the solenoid valve with transistor, characterized in that between one source terminal (2) of the collector 3 and the emlor 4, which is simultaneously the current of the winding 1, significantly decreases. In this state, the valve is already open and substantially less current than required to open it is sufficient to keep it open. As the current drops, the power consumption required to keep the valve open decreases proportionally. The use of a transistor enables, in contrast to a conventional series or series parallel connection of a winding with a resistor or a resistor, to realize a circuit with a posistor of conventional design, whose rated currents are of the order of magnitude equal to those of the base of the power transistors. The time of heating and transition of the resistor of a conventional design into the area of greater resistance is suitable for _the above mentioned application on valves.