SU144648A1 - Device for automatic temperature control in industrial furnaces - Google Patents

Description

At present, devices for automatic control are known, comprising a temperature sensor connected to an electronic potentiometer circuit operating on an additional fuel delivery mechanism through an isodromic regulator equipped with a feedback rheostat corrector.

Unlike those known in the proposed device, a rheostat fuel consumption sensor is used, which forms a bridge with the feedback rheostat, the imbalance of which, when the fuel consumption changes, provides for automatic adjustment of the controller during a given process mode. This change made it possible to improve the quality of temperature control and ensure fuel economy in furnaces under conditions of significant fluctuations in heat load.

The drawing shows a schematic diagram of a device operating as follows. In the flow meter / built-in rheostat sensor 2; a bridge circuit component with a feedback rheostat 3 of the corrective device. The power supply of the bridge circuit is carried out by alternating voltage from the secondary winding of the power transformer 4 and is supplied through the variable resistance motors 5 and 6, which change the setting of the correction device.

When the fuel consumption changes, the voltage of the imbalance of the bridge circuit is applied to the input transformer 7.

Resistance 8 serves to adjust the sensitivity of the device, determining the magnitude of the input signal.

From the secondary winding of the transformer 7, the imbalance signal is applied to the grid of the electronic balance relay, made on a double triode 9. In the anode circuit of the right half of the lamp is connected an electronic 144648 2-tron relay 10 having a pair of contacts. Resistance // adjusts the amount of current in the anode circuit at which both contacts of the relay are open. The power of the anode circuit and the filament circuit is supplied from transformer 4. Depending on the phase of the imbalance signal coming from the bridge circuit through the transformer 7, the anodic current of the left half of the lamp varies. The voltage drop across the resistor 12 from the anode current of the left half of the lamp is the control grid voltage that determines the magnitude of the anode current of the right half of the lamp, which triggers the contacts of the relay 10. The contacts of the relay 10 turn on the motor 13. The capacitor / 4 bypass relay , eliminates the vibration of the core.

Capacitor 15 eliminates the effect of supply voltage fluctuations on the magnitude of the anode current. Variable resistance 16 adjusts the rotational speed of the engine 13 during tuning. Resistance 17 sets the magnitude of the degree of non-uniformity in the controller simultaneously with the displacement of the resistance slider 3, which leads the bridge to an equilibrium state. In the extreme positions, the engine power supply is interrupted by limit switches 18 and 19. Regulator 20 has a switch 21 on which the ends of the rheostat 22 and the rheostat 17 are output. The resistor 17 is connected to the correcting correction device 22 - removing it. The correction device is used in conjunction with standard equipment commonly used in industrial furnaces.

Subject invention

A device for automatic temperature control in industrial furnaces, comprising a temperature sensor included in an electronic potentiometer circuit acting on the actuator for feeding the fuel through an isodromic regulator equipped with a feedback rheostat corrector, characterized in that, in order to improve the quality of regulation, corrector, a rheostat fuel consumption sensor is used, which forms a bridge with the feedback rheostat, the imbalance of which, when the fuel consumption changes, provides an automatic This is the setting of the controller for a given technological mode.