CN203788480U

CN203788480U - Circuit for controlling metal ceramic heating element through bidirectional silicon controlled rectifier

Info

Publication number: CN203788480U
Application number: CN201420171972.2U
Authority: CN
Inventors: 陈佳建; 徐琦
Original assignee: SHANGHAI FOYOUNG MICROELECTRONICS Co Ltd
Current assignee: SHANGHAI FOYOUNG MICROELECTRONICS Co Ltd
Priority date: 2014-04-10
Filing date: 2014-04-10
Publication date: 2014-08-20
Anticipated expiration: 2024-04-10

Abstract

The utility model relates to the technical field of electricity and silicon controlled rectifier, in particular to a circuit for controlling a metal ceramic heating element through a bidirectional silicon controlled rectifier. The circuit comprises a special temperature control integrated circuit U1, KC-0.5, 80C51, LM3911 or an integrated circuit having signal acquisition, calculation, output, voltage stabilization, control key input and display input functions, a bidirectional silicon controlled rectifier, a ceramic metal heating body, resistors and capacitors. The circuit is characterized in that the circuit is formed by comprising the special temperature control integrated circuit U1, the bidirectional silicon controlled rectifier Q1, the ceramic metal heating body R5, a sampling resistor, a negative power source supply circuit, an AC clock and an AC voltage sampling circuit. Compared with the prior art, the circuit has the advantages that an AC signal input to a CLK pin of the integrated circuit U1, the integrated circuit U1 is integrally provided with the AC clock and the sampling circuit for calculating the accurate zero-crossing point of an alternating current and measuring the AC voltage value, and a GATE pin outputs a negative voltage pulse at the zero-crossing point of the alternating current when in need of heating, so that the bidirectional silicon controlled rectifier is conducted to realize stable and reliable temperature control.

Description

A kind of relevant bidirectional triode thyristor is controlled the circuit of metal ceramic heating body

[technical field]

The utility model relates to electricity and controllable silicon technical field, is the circuit that a kind of relevant bidirectional triode thyristor is controlled metal ceramic heating body specifically.

[background technology]

MCH refers to tungsten or molybdenum manganese slurry is printed on ceramic curtain coating base substrate; through hot pressing lamination; then under 1600 ℃ of nitrogen atmosphere protections; the ceramic heating element that pottery and the common sintering of metal form; there is the advantages such as corrosion-resistant, high temperature resistant, the life-span is long, energy-efficient, temperature is even, heat conductivility is good, thermal compensation speed is fast; and the harmful substance such as not leaded, cadmium, mercury, Cr VI, Polybrominated biphenyl, PBDEs, meet the environmental requirements such as the RoHS of European Union.MCH(metal ceramic heating body) heater has been widely used in small household electrical appliance, the feature of this heater maximum is that its resistance value has ptc characteristics, and the linearity is fine, can utilize this characteristic to go to measure working face temperature, MCH heater not only can be used as heater but also can be used as temperature sensor in the product of heating like this, not only make the circuit of system and the installation of complete machine be simplified, and due to the installation site that does not have temperature sensor problem improperly, the fail safe of product is also greatly improved.

China Patent No. 200810038919.4 discloses a kind of temperature control circuit for positive temperature coefficient heating element, at this one-way SCR, control in the circuit of MCH heater, positive half cycle at additional alternating current, switch k1 is closed, switch k2 opens, control circuit provides triggering signal 1 and triggers SCR, and heater is heated in this half cycle; At the negative half period of additional alternating current, switch k1 opens, and SCR no longer triggers, and switch k2 is closed, and control circuit provides a direct voltage 2, and by the dividing potential drop of sampling resistor RS and heater resistance R H, a voltage signal is sampled 3.This method adopts one-way SCR to control, positive half cycle at additional alternating current heats, and negative half period carries out thermometric, for some, need the product of fast heating, the resistance value that reduces MCH with regard to having to adds high-power, has so increased thermometric difficulty, has increased system power dissipation, so, only have by all-wave and heat and could under the prerequisite that does not reduce resistance value, increase power.

The patent of invention that current existing China Patent No. is 200910194722.4 discloses a kind of circuit of controlling MCH heater with bidirectional triode thyristor through reasoning and actual test, and two-way in its circuit cannot triggered as normal, cannot normally work.

[utility model content]

The purpose of this utility model is in order to overcome above-mentioned defect, according to circuit design principle and bidirectional triode thyristor application technology knowledge, starting signal in integrated circuit or single-chip computer control system is loaded into silicon controlled and controls the utmost point, a kind of control circuit of bidirectional triode thyristor control MCH heater of novel structure is provided for reducing the interference of circuits for triggering.

To achieve these goals, design a kind of relevant bidirectional triode thyristor and control the circuit of metal ceramic heating body, comprise U1 Special temp controller integrated circuit KC-0.5, 80C51, LM3911 or there is signals collecting, calculate, output and voltage stabilizing and control key input, the integrated circuit that shows output, bidirectional triode thyristor, ceramet heater, resistance capacitance element, this circuit is by Special temp controller control integration circuit U 1, bidirectional triode thyristor Q1, ceramet heater R5, sampling resistor, negative supply power supply circuits, exchanging clock and alternating voltage sampling circuit connects to form, GND end ground connection tap one end of integrated circuit U1 connect alternating current zero line, the PTC thermistor signal line of integrated circuit U1 is connected with resistance R 1 one end, and tap one line is connected with the T2 terminal of bidirectional triode thyristor Q1, resistance R 1 other end is connected with ground wire GND end, signal enabling end GATE contact resistance R2 one end of integrated circuit U1, resistance R 2 other ends connect the control utmost point G of bidirectional triode thyristor Q1, the T1 terminal of bidirectional triode thyristor Q1 is connected with ceramet heater R5 one end, the clock cable CLK end of integrated circuit U1 is connected with resistance R 3 one end, and tap two lines respectively with resistance R 4, capacitor C 1 one end is connected, resistance R 4, capacitor C 1 other end ground connection, negative voltage power supply signal line VEE end contact resistance R6 one end of integrated circuit U1, and tap two lines respectively with capacitor C 2, capacitor C 3 one end are connected, capacitor C 2 and C3 other end ground connection, resistance R 6 other ends connect the positive pole of diode D1, the negative pole of diode D1 connects alternating current fire wire, and tap two lines connect respectively the other end of ceramet heater R5 and resistance R 3, described resistance R1 is 0.1 Ω, R2 is 100 Ω, R3 is 1M, R4 is 8.2K, R6 is 20K-2W, capacitor C 3 is 47uF/10V, realize reliable and stable temperature control.

Sampling resistor is R1, according to resistance R 1 voltage above, draws the electric current in ceramet heater R5.

Exchange clock and alternating current sampling circuit and be comprised of resistance R 3, capacitor C 1, resistance R 4, the CLK end that signal is inputed to integrated circuit U1 calculates for U1.

Negative voltage power supply circuits route diode D1, resistance R 6, capacitor C 2 and C3 form, and are responsible for providing a VEE who bears the power supply supply integrated circuit U1 of 5 volts to hold, and in integrated circuit U1, are provided with shunt regulating circuit; In having the circuit of different additional functions, the numerical value of R6 and C3 can be made corresponding adjustment.

SCR control limit leakage resistance is R2, for adjusting silicon controlled trigger current, from adapting to the controllable silicon of different model.

The output of integrated short circuit U1 is provided with LED or LCD display circuit, button or other peripheral circuits needing according to design.

The utility model compared with the existing technology, its advantage is: the CLK pin that AC signal is input to integrated circuit U1, integrated circuit U1 inside has digitized interchange clock sampling circuit to calculate the accurate zero crossing of alternating current, measure ac voltage simultaneously, in the time need to heating, GATE pin can be exported negative potential pulse at zero-crossing of alternating current, makes bidirectional triode thyristor conducting, thereby realizes reliable and stable temperature control, working stability, reliability is high.

[accompanying drawing explanation]

Fig. 1 is the circuit diagram that the utility model bidirectional triode thyristor is controlled MCH heater;

Fig. 2 is the embodiment that the utility model bidirectional triode thyristor is controlled the circuit of MCH heater;

Referring to Fig. 1 and Fig. 2, U1 is Special temp controller integrated circuit, being responsible for signals collecting, calculating, output and key-press input, demonstration output etc., is a part for circuit system in figure, and the circuit such as other button, demonstration can have kinds of schemes selective according to client's demand; Q1 is bidirectional triode thyristor, is the control unit of heating wire heating, in order to realize cut-offfing of heating unit power; R5 is ceramet heater; R1 is sampling resistor, can draw according to voltage above the electric current in heating wire; R3, C1 forms and exchanges clock and alternating voltage sampling circuit with R4, and the CLK pin that signal is inputed to U1 calculates for U1; D1, R6, C2, C3 is negative voltage power supply circuits, and being responsible for provides the power supply of negative 5 volts to supply with the VEE pin of U1 to system, and there is shunt regulating circuit U1 inside; R2 is SCR control limit leakage resistance, for adjusting silicon controlled trigger current, to adapt to the controllable silicon of different model;

Specify Fig. 1 as Figure of abstract of the present utility model.

[embodiment]

Below in conjunction with accompanying drawing, the utility model is described in further detail, and the structure of this device and principle are very clearly concerning this professional people.Should be appreciated that specific embodiment described herein is only in order to explain the utility model, and be not used in restriction the utility model.

Embodiment 1

As shown in Figures 1 and 2, a kind of bidirectional triode thyristor that uses realizes that ceramet heater heats and the temperature-adjusting circuit figure of sensing, circuit comprises special-purpose control integration circuit, bidirectional triode thyristor, sampling resistor, negative supply power supply circuits, exchange clock and alternating voltage sampling circuit, circuit gathers external communication voltage over zero by CLK pin and U1 internal digital zero passage sample circuit, GATE pin is opened controllable silicon in voltage over zero output negative pulse, in turn on process, by PTC pin, gather the voltage on sampling resistor R1, obtain the electric current in sampling resistor, according to the voltage on CLK pin, draw the supply voltage of synchronization simultaneously, calculate the resistance of ceramic heating element, thereby obtain its internal temperature, the temperature of heater in heating, detected, and the data passing ratio such as the integrated temperature rate of rise and absolute value changes to determine whether need to continue heating, thereby realize reliable and stable temperature control.

D1 in native system, 46, C2, C3 coordinates the shunt regulating circuit in integrated circuit U1, be responsible for changing out stable negative 5 volts of power supplys from the alternating current of 120 volts or 220 volts, for whole system, in having the circuit of different additional functions, the numerical value of R6 and C3 can be made corresponding adjustment.

System is by R3, and C1 and R4 are input to AC signal the CLK pin of integrated circuit U1, and integrated circuit U1 inside has digitized interchange clock sampling circuit to calculate the accurate zero crossing of alternating current, measures ac voltage simultaneously.

In the time need to heating, GATE pin can be exported negative potential pulse at zero-crossing of alternating current, make bidirectional triode thyristor conducting, when voltage peak, system can gather the voltage of PTC pin and the voltage of CLK pin simultaneously, data are given U1 internal logic control unit, calculate the current temperature of ceramic heating element, and determine whether need to continue heating according to data behaviours in service such as the rates of change of temperature, thereby realize reliable and stable temperature control.

Wherein target temperature can be set by button or potentiometer, and design temperature and Current Temperatures content can show by LED or LCD.

Claims

1. a relevant bidirectional triode thyristor is controlled the circuit of metal ceramic heating body, comprise U1 Special temp controller integrated circuit KC-0.5, 80C51, LM3911 or there is signals collecting, calculate, output and voltage stabilizing and control key input, the integrated circuit that shows output, bidirectional triode thyristor, ceramet heater, resistance capacitance element, it is characterized in that this circuit is by Special temp controller control integration circuit U 1, bidirectional triode thyristor Q1, ceramet heater R5, sampling resistor, negative supply power supply circuits, exchanging clock and alternating voltage sampling circuit connects to form, GND end ground connection tap one end of integrated circuit U1 connect alternating current zero line, the PTC thermistor signal line of integrated circuit U1 is connected with resistance R 1 one end, and tap one line is connected with the T2 terminal of bidirectional triode thyristor Q1, resistance R 1 other end is connected with ground wire GND end, signal enabling end GATE contact resistance R2 one end of integrated circuit U1, resistance R 2 other ends connect the control utmost point G of bidirectional triode thyristor Q1, the T1 terminal of bidirectional triode thyristor Q1 is connected with ceramet heater R5 one end, the clock cable CLK end of integrated circuit U1 is connected with resistance R 3 one end, and tap two lines respectively with resistance R 4, capacitor C 1 one end is connected, resistance R 4, capacitor C 1 other end ground connection, negative voltage power supply signal line VEE end contact resistance R6 one end of integrated circuit U1, and tap two lines respectively with capacitor C 2, capacitor C 3 one end are connected, capacitor C 2 and C3 other end ground connection, resistance R 6 other ends connect the positive pole of diode D1, the negative pole of diode D1 connects alternating current fire wire, and tap two lines connect respectively the other end of ceramet heater R5 and resistance R 3, described resistance R1 is 0.1 Ω, R2 is 100 Ω, R3 is 1M, R4 is 8.2K, R6 is 20K-2W, capacitor C 3 is 47uF/10V.

2. a kind of relevant bidirectional triode thyristor as claimed in claim 1 is controlled the circuit of metal ceramic heating body, it is characterized in that sampling resistor is R1, according to resistance R 1 voltage above, draws the electric current in ceramet heater R5.

3. a kind of relevant bidirectional triode thyristor as claimed in claim 1 is controlled the circuit of metal ceramic heating body, it is characterized in that exchanging clock and alternating current sampling circuit and be comprised of resistance R 3, capacitor C 1, resistance R 4, the CLK end that signal is inputed to integrated circuit U1 calculates for U1.

4. a kind of relevant bidirectional triode thyristor as claimed in claim 1 is controlled the circuit of metal ceramic heating body, it is characterized in that negative voltage power supply circuits route diode D1, resistance R 6, capacitor C 2 and C3 form, the VEE end that provides one to bear the power supply supply integrated circuit U1 of 5 volts is provided, in integrated circuit U1, is provided with shunt regulating circuit; In having the circuit of different additional functions, the numerical value of R6 and C3 can be made corresponding adjustment.

5. a kind of relevant bidirectional triode thyristor as claimed in claim 1 is controlled the circuit of metal ceramic heating body, it is characterized in that SCR control limit leakage resistance is R2, for adjusting silicon controlled trigger current, from adapting to the controllable silicon of different model.

6. a kind of relevant bidirectional triode thyristor as claimed in claim 1 is controlled the circuit of metal ceramic heating body, and the output that it is characterized in that integrated short circuit U1 is provided with LED or LCD display circuit, button or other are according to the peripheral circuit of design needs.