SU767723A1 - Device for program temperature control - Google Patents

Description

(54) DEVICE FOR PROGRAM REGULATION

TEMPERATURES

one

The invention relates to technical means of temperature control and can be used for precision temperature control of an electric furnace with a wide range of temperature program variations.

A device for programmed temperature control is known, which contains an executive motor and profiled cams, which set the temperature change program 1.

The disadvantage of this device lies in the low accuracy of reproduction of temperature programs, especially during complex temperature cycles, which is explained by the difficulties in accurately fabricating the desired cam profile.

It is also known a device for software temperature control, comprising a temperature setting motor with its speed control unit and a commander 2.

A disadvantage of this device is the complexity of the fine tuning of the controller and the associated low convergence of temperature programs.

The closest to the technical essence of the invention is a device for software temperature control, comprising a serially connected start block and a clock generator, J to the first output of which is connected the first input of the time delay block, as well as the setpoint for the rate of temperature change, decoder, switch , binary counter, first and second cursers 3.

The disadvantage of this device {) is 10 that its functionality is limited due to the insufficient variety of the programs it implements. The complication of the program (for example, the introduction of additional isothermal steps during heating or cooling) cannot be

15 is implemented by this device without significant changes in its structure and internal communications between the blocks.

The purpose of the invention is to expand the field of application and increase the reliability of the device.

The goal is achieved by the fact that in the device for software temperature control the second output of the unit is started, as it is connected to the first inputs of the binary

the counter and switch, with the second input of which the output of the time delay block is connected, and with the outputs of the second input of the time delay block and serially connected binary counter and decoder, to the output of which the third input of the time delay block and the setpoint input are connected via the first and second encoders rate of change of temperature.

A block diagram of a device for software temperature control is shown in the drawing.

The device contains a start block 1, a clock generator 2, a block of 3 time delays, a setpoint 4 of the rate of temperature change, a decoder 5, a binary counter 6, a switch 7, the first 8 and the second 9 encoders.

Unit 3 is designed to form a predetermined time delay and consists of a transfer element 10 and a counter 11.

The setting device 4 serves to generate the output signal corresponding to the temperature rise rate specified on each program section, and consists of a generator 12 pulses of variable frequency, an integrator 13 and an output element 14.

The device works as follows.

Initially, in the encoders 8 and 9, the duration of each section of the temperature program and the rate of temperature rise on them is established for a given technological process (at a zero rate of temperature rise, an isothermal holding step will be obtained). When pressing the Start button, the start-up unit 1 turns on the 2-clock pulse generator and outputs a short-term signal to switch 7, which opens transfer element 10, and binary counter 6, which is forcibly set to the position "1 corresponding to the first section of the program." At the first output bus, not the decoder 5, a signal appears that enters the encoders 8 and 9. When this occurs, the parallel time code of the specified time interval of the first segment from the encoder 8 is transferred through the transfer element 10 to the counter 11.. Simultaneously through the encoder 9, an impulse generator 12 is turned on, which operates at a frequency corresponding to a predetermined rate of increase in temperature in the first program section. The integrator 13 converts these pulses to a voltage varying at a predetermined speed, which is then fed to the output element 14.

The counter 11 of the time-delay block 3 counts down the clock pulses (when the pulses are counted, the counter readings decrease). .

Essentially, this counter records the time remaining to the end of the program area. When the counter is reset at the end of the program section, a signal appears at its output, which, via switch 7, reopens transfer element 10 and puts binary counter 6 into the state

“2, corresponding to the second section of the program. The signal now appearing on the second output terminal of the decoder 5 carries out the transfer in parallel code of the duration of the second section of the program from the decoder 8 through transfer element 10

into counter 11. At the same time, a new frequency of the pulse generator 12 is set through the tuner 9, corresponding to a predetermined rate of temperature change in the second section of the program.

Similarly, changes in the duration and rate of change in temperature occur in other parts of the program.

The device provides the formation of temperature programs with any number of plots and a wide range of time delays and rates of temperature change on them. This expands the functionality of the device and allows it to be used to programmatically control the temperature of electric furnaces of various technological purposes.

Counter 11 counts down and stores information related to only one section of the program. Therefore, its failure does not affect the duration of others.

0 program sites. The command to change the number of the area occurs when the counter is reset to 11, which fundamentally excludes the possibility of skipping the area due to the failure of this counter during the counting process. This increases the reliability of the device.

Claims (3)

Invention Formula A device for software temperature control, containing a serially connected start block and a clock generator, to the first output of which the first input of the time delay block is connected, as well as the setpoint for the rate of temperature change, decipher, switch, binary counter, first and second encoders, characterized in that in order to expand the application area and increase the reliability of the device, the second output of the start-up unit is connected to the first g inputs of a binary counter and a switch, the second input of which is associated with the output of a time delay block, and outputs a second input of the time delay block and a serially connected binary counter and decryptor, the third input of the time delay block is connected to the output of the first and second encoders respectively and an input of the setpoint for the rate of temperature change. five Sources of information taken into account in the examination of 1 USSR author's certificate 160390, cl. G 05 D 23/19, 1960. 767723 2. USSR author's certificate number 200925, cl. G 0.5 D 23/19, 1963. 3. USSR author's certificate No. 498608, cl. G 05 D 23/19, 1974 (prototype).