SU1767482A2 - Temperature regulator - Google Patents

Abstract

The invention relates to the field of temperature control and can be used in various process control systems. The purpose of the invention is to increase the reliability of the controller and reduce its interference. The controller contains a temperature sensor and setpoint adjuster, a differential amplifier, a comparator, an executive element, an inverting amplifier, an analog multiplexer, and an integration unit. In addition, two D-triggers and a Schmitt trigger are introduced into the device, which synchronize the control signal from the output of the comparator with the frequency of square pulses produced at the output of the Schmitt trigger fed from the source of the network frequency. 2 Il.

Description

The invention relates to the field of temperature control, can be used in various process control systems and is an improvement of the temperature controller according to the authors. St. No. 1612282.

The purpose of the invention is to increase the reliability and reduce the noise generated by the controller.

FIG. 1 is a functional diagram of a temperature controller: FIG. 2 - time diagrams.

The controller contains a temperature sensor 1, a setpoint generator 2, a differential amplifier 3, a comparator 4, an inverting amplifier 5, an analog multiplexer 6, an integration unit 7, D-triggers 8 and 9, a Schmitt trigger 10, an actuator 11.

The regulator works as follows.

When the signal value at the output of sensor 1 is less than the value of the setpoint at the output of comparator 4, a high level control signal Y is generated, which is fed to the R input of a D-trigger 8. Before switching the comparator 4, this signal maintains a high level (time). 2). Upon reaching the sensor signal value of the setpoint, the level of the control signal Y becomes low, but this does not affect the state of the D-flip-flops 8 and 9. They switch only after the signal b takes the value corresponding to the high level (time t2) . At the output of D-flip-flop 8, the signal d has a high level, and at the output of D-flip-flop 9, the signal e is low, which corresponds to the disconnected state of the actuator 11. When the level of the control signal Y becomes high (moment ts), the next state change of D flip-flop 8, but this does not lead to instantaneous

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the D-flip-flop 9 is switched off, which is switched only with the appearance of a high level signal b at its C-input, i.e. at the time of the next passage of the sine wave of the mains voltage through zero (time t /)). The description of the circuit is given for the case when the change in the level of the control signal Y occurs at a negative half-wave of the signal. If a level change occurs at a positive half-wave, the process proceeds similarly. The time points of the corresponding switchings at

THIS, t2, t3, t4.

Thus, the control signal Y is synchronized with the network frequency (a) and the signals generated at the output of D-flip-flop 9 enable the load to be switched on and off at the moments when the mains voltage sine wave passes through

zero, due to which the conditions of operation of the actuating element are significantly improved, which provides increased reliability of the device, as well as reduced interference.

Claims (1)

Claims of invention Regulus cake temperature av. Sv. No. 1612282, characterized in that, for the purpose of increasing its reliability and reducing the interference it generates, the controller contains two D-flip-flops and a Schmitt flip-flop, with the Schmitt-flip-flop input connected to the source of the network frequency, and the output to C-inputs D-flip-flops, the R-input of the first of which is connected to the output of the comparator, and the R-input and output of the second D-flip-flop, respectively, with the output of the first D-flip-flop and the input of the actuator. BUT D / -J / UlTT / l / V TO U W W M ;,, v,, vi ivi jVi it, U | iVj, Vr | V,, v,, u, | Vi | V | iv, (v i i i i i i i i i i i i i i i i i i i i i i i i i i PPPPPPPPPPPG BUT D / l / v to u w u m