SU1179292A1 - Temperature controller - Google Patents

Abstract

1. A DEVICE FOR REGULATING TEMPERATURE containing a primary and secondary temperature sensors, a temperature setpoint, a first reference element, an actuator and a load connected in series, the main sensor and the temperature setting device being connected to the two inputs of the first reference element, respectively, characterized in that increase the accuracy, it contains the second element of comparison, the memory block, the nullorgan connected in series and the element with a controlled delay connected by the output to the input of the pack A memory unit, the input of which is connected with an additional temperature sensor and one of the inputs of the second comparison element, and the output with another input of the second comparison element, the output of which is connected to the third input of the first comparison element, the output of which is connected to the zero-body input . 2. The device according to claim 1, characterized in that the element with a controlled delay contains in series the delay element and the first key, in parallel with (the second key is connected.

Description

The invention relates to automation and can be used to regulate thermal processes in electric furnaces during the heat treatment of gas discharge devices, their parts and assemblies, as well as other products.

The purpose of the invention is to improve accuracy.

FIG. 1 shows a block diagram of the device; in fig. 2 - graphs of temperature change at the place of installation of temperature sensors during lifting, holding and decreasing temperature according to a given program (curve I - temperature graph in the case of building a temperature controller according to the prototype scheme and installing the main temperature sensor near the heated product; curve II - temperature graph, shown by the main, and III - additional temperature sensor in the proposed device; the dotted line shows the temperature change in the absence of input elements in the device).

The device contains a main temperature sensor 1, a temperature setpoint 2, a first element of comparison 3, an execution unit 4 consisting of a regulating unit 5, a thyristor control unit 6 and a thyristor unit 7, a load 8, which is a heater.

The nodes are connected according to the usual thermostatic scheme and constitute the main circuit of the automatic temperature control system.

The device contains an additional temperature sensor 9, a memory unit 10 and a second reference element 11 connected to the third input of the first reference element 3 and comprising an additional control loop. A zero-element 12 element with a controlled delay 13 is connected to the output of the first element of comparison 3, which is intended to activate an additional control loop when the temperature reaches a predetermined value. The main temperature sensor 1 is located near the heater 8, and the additional sensor 9 is near the heated product. The controllable delay element 13 consists of a delay element 14 and a first key 15 connected in series, and a second key 16 connected in parallel to them.

The device for temperature control works as follows.

When the heating is turned on, the first element of comparison 3 is supplied with a signal from setpoint 2, the signal from the main sensor 1 is zero, the first element of comparison 3 generates a positive polarity mismatch signal that is fed to the executive unit 4, which turns on the power to the heater 8, the temperature in the furnace begins to rise by reducing the error signal, i.e., the main control loop is operating. The zero unit 12, through the second key 16 of the element with controlled delay 13, switches on without delay the memory block 10 to the signal sample, and the same signal from the additional temperature sensor 9 is applied to both inputs of the second element of the comparison 11, resulting in a signal from the second Comparison element 11 is zero and the additional control loop does not work.

When the temperature measured by the main sensor 1 reaches the specified value, the null organ 12 through the delay element 14 and the first key 15 of the element with controlled delay 13 turns off the memory block from the signal sampling mode, the second comparison element 11 outputs the additional element of the first comparison element 3, the error signal between the memorized in the memory unit 10 and the current temperature value measured by the additional sensor 9. Thus, a correction is made to the temperature of the heater 8, measured by the main sensor 1, by the value of tim temperature at the installation site of the heated article in the soaking process.

The element with controlled delay 13 is designed to delay the start of operation of the memory unit in the information storage mode by the time it takes for the temperature to be established near the heated product relative to the temperature near the heater 8. The element with controlled delay 13 can also be made at a time relay.

In parallel, the inclusion of the first key 15 with the delay element 14 and the second key 16 allows the memory unit 10 to be turned on.

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FIG. 2

Claims (2)

1. DEVICE FOR REGULATING A TEMPERATURE, comprising a primary and secondary temperature sensors, a temperature sensor, serially connected to the first comparison element, the Executive unit and the load, and the main sensor and temperature sensor are connected respectively to two inputs of the first comparison element, characterized in that, for the purpose improving accuracy, it contains a second comparison element, a memory block, a null organ connected in series and a controlled delay element connected by an output to the control input tions of the storage unit, the input of which is connected with an additional temperature sensor and one input of a second comparison element, and an output - to the other input of the second comparing element whose output is connected to the third input of the first comparing element whose output is connected to the input zero-organ. 2. The device according to π. 1, characterized in that the element with a controlled delay contains a series-connected delay element and a first key, in parallel with which a second key is connected. Pue.j