CN201212960Y - Linear constant temperature controller - Google Patents

Abstract

The utility model relates to a thermostatic controller of household appliances, in particular to a linear thermostatic controller which can realize the linear temperature control. The thermostatic controller comprises a thermal resistor RT, a sample circuit, a 555 integrated circuit and a power control circuit, wherein one end of the thermal resistor is connected with the sample circuit, the sample circuit is connected with the 2 pin, the 6 pin, and the 7 pin of the 555 integrated circuit, the other end of the thermal resistor RT is respectively connected with a direct current supply Vcc and the 4 pin and the 8 pin of the 555 integrated circuit, and the 3 pin of the 555 integrated circuit is connected with the power control circuit. Because the thermostatic controller is provided with the sample circuit, when the temperature of the thermal resistor RT raises, a bidirectional thyristor is blocked through sampling, the power supply is cut off, the temperature is enabled to lower; when the temperature of the thermal resistor RT reduces to the preset value, the bidirectional thyristor is conducted, the temperature raises, thereby the temperature of the thermal resistor RT is kept within a certain range, and people feel comfortable and safe. The utility model has simple circuit, is easy to be implemented, and is suitable for using in the temperature control of the household appliances.

Description

Linear radiator valve

Technical field

The utility model is a kind of household electrical appliance radiator valve, the particularly a kind of linear radiator valve that can realize linear temperature control.

Background technology

Traditional temperature controller carries out the temperature control period, when being heated device temperature and being increased to design temperature, temperature controller can send signal and stop heating, but the temperature that at this moment is heated device also often continues to be raised several degrees, just begin then to descend, prescribe a time limit when dropping to the following of design temperature, temperature controller begins to send the signal of heating again, begins to reheat, but when reheating, the temperature that is heated device also often continues the several years that descend, so traditional temperature controller has the error in positive and negative several years.And linear what need is thermostatic control, so the error in the positive and negative several years of traditional temperature controller just can not satisfy thermostatically controlled demand.

Summary of the invention

The purpose of this utility model is in order to overcome the defective that traditional temperature controller has positive and negative several years error, invents a kind ofly to make temperature keep within the specific limits linear radiator valve by sampling.

The purpose of this utility model realizes as follows: described linear radiator valve comprises thermistor R _T, sample circuit, 555 integrated circuit and power control circuit, an end of thermistor is connected with sample circuit, sample circuit is connected thermistor R with 2,6,7 pin of 555 integrated circuit _TThe other end be connected with 4,8 pin of direct supply Vcc and 555 integrated circuit respectively, 3 pin of 555 integrated circuit are connected with power control circuit.

Described thermistor R _TModel be MF13.

Described sample circuit is made up of R3, R1, R2, and R3, R1, R2 series connection back are connected with 1 pin with 7 pin of 555 integrated circuit.

Described R1=0, R2=176k Ω, R3=1.7k Ω.

The model of described 555 integrated circuit is NE555.

Described power control circuit is made up of R4, controllable silicon SCR and supply socket K, and power control circuit is connected with 3 pin of 555 integrated circuit by R4.

Described R4=1k Ω.

The model of described controllable silicon SCR is BT169.

Good effect of the present utility model is as follows: because the utility model is provided with sample circuit, by sampling, as thermistor R _TTemperature raises constantly, and the bidirectional triode thyristor blocking-up is cut off the electricity supply, and temperature is reduced, as thermistor R _TWhen temperature is hanged down to preset value, the controllable silicon conducting, temperature rises, thereby makes thermistor R _TTemperature keeps within the specific limits, and the people is felt comfortably cool and safety.The utility model circuit is simple, is easy to realize, is adapted at using in the control of household electrical appliance temperature.

Description of drawings

Fig. 1 is the utility model circuit block diagram

Fig. 2 is the utility model circuit theory diagrams

Embodiment

Shown in Figure 2 as Fig. 1, described linear radiator valve comprises thermistor R _T, sample circuit, 555 integrated circuit and power control circuit, an end of thermistor is connected with sample circuit, sample circuit is connected thermistor R with 2,6,7 pin of 555 integrated circuit _TThe other end be connected with 4,8 pin of direct supply Vcc and 555 integrated circuit respectively, 3 pin of 555 integrated circuit are connected with power control circuit.

Described thermistor R _TModel be MF13.Thermistor R _TBe used for detecting temperature.

Described sample circuit is made up of R3, R1, R2, and R3, R1, R2 series connection back are connected with 1 pin with 7 pin of 555 integrated circuit.Sample circuit is mainly finished thermistor R _TTemperature variation sampling, the precision prescribed height can be selected 1% precision resistance for use.

Described R1=0, R2=176k Ω, R3=1.7k Ω.

The model of described 555 integrated circuit is NE555.

Described power control circuit is made up of R4, controllable silicon SCR and supply socket K, and power control circuit is connected with 3 pin of 555 integrated circuit by R4.

Described R4=1k Ω.

The model of described controllable silicon SCR is BT169.

Described direct supply V _CCAvailable 9V basic unit battery, or 9 to 12V DC voltage-stabilizing module.

During concrete the use, this circuit can be located in the supply socket, thermistor R _TBe drawn out to the position that needs thermometric,, fix then and get final product as electric blanket, electric iron, incubator, electric heater.

Principle of work of the present utility model is as follows: 555 integrated circuit work in bistable, and R1, R2, R3 constitute sample circuit, when being raise by controlling temperature, and thermistor R _TResistance reduces, the 6th pin current potential of 555 integrated circuit increases, being reached predefined by controlling temperature goes up in limited time, the 6th pin potential rise of 555 integrated circuit is to 2/3Vcc, 555 integrated circuit reset, its the 3rd pin becomes low level, makes the bidirectional triode thyristor blocking-up, and the firing equipment of being controlled quits work because of non-transformer; After 555 integrated circuit resetted, the discharge tube conducting of the 7th pin inside was equivalent to the 7th pin ground connection.Along with by the reduction of controlling temperature, R _TGet resistance and increase, the 2nd pin current potential of 555 integrated circuit is reduced.When being reached predefined lower limit temperature by controlling temperature, 555 the 2nd pin current potentials equal 1/3Vcc, trigger 555 integrated circuit set again, and its 3rd pin output high level makes the bidirectional triode thyristor conducting, controlled firing equipment energized work.Like this, temperature controller has just been realized and will be controlled at certain limit by controlling temperature.

The resistance of thermistor in the circuit, when being reached predefined ceiling temperature by controlling temperature, the resistance R of its thermistor _{On the T}, and the relation between R1, the R2 should satisfy:

When being reached predefined lower limit temperature by controlling temperature, the resistance R of its thermistor _{Under the T}, and concern and should satisfy between R1, R2, the R3:

Wherein: $R3//(R1+R2)=\frac{R3(R1+R2)}{R1+R2+R3)}$

Thermistor R _TResistance choose very important, as known R _TResistance vary with temperature when concerning, should be according to R _{Under the T}/ R _{On the T}Value decide the resistance of R1, R2, R3.If R _{Under the T}/ R _{On the T}=n is as n 〉=2, then R2=nR _{On the T}, substitution (1) formula: R1=(0.5n-1) R _{On the T}With expression formula substitution (2) formula of R1, R2,

:

If n π 2 then gets: R1=0, R2=2R _{On the T}, substitution (2) formula gets:

Claims (8)

1. linear radiator valve, described linear radiator valve comprises thermistor R _T, 555 integrated circuit and power control circuit, it is characterized in that: also comprise sample circuit, an end of thermistor is connected with sample circuit, sample circuit is connected thermistor R with 2,6,7 pin of 555 integrated circuit _TThe other end be connected with 4,8 pin of direct supply Vcc and 555 integrated circuit respectively, 3 pin of 555 integrated circuit are connected with power control circuit.

2. linear radiator valve according to claim 1 is characterized in that: described thermistor R _TModel be MF13.

3. linear radiator valve according to claim 1 is characterized in that: described sample circuit is made up of R3, R1, R2, and R3, R1, R2 series connection back are connected with 1 pin with 7 pin of 555 integrated circuit.

4. linear radiator valve according to claim 3 is characterized in that: described R1=0, R2=176k Ω, R3=1.7k Ω.

5. linear radiator valve according to claim 1 is characterized in that: the model of described 555 integrated circuit is NE555.

6. linear radiator valve according to claim 1 is characterized in that: described power control circuit is made up of R4, controllable silicon SCR and supply socket K, and power control circuit is connected with 3 pin of 555 integrated circuit by R4.

7. linear radiator valve according to claim 6 is characterized in that: described R4=1k Ω.

8. linear radiator valve according to claim 6 is characterized in that: the model of described controllable silicon SCR is BT169.

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