JPS58136961A - Control circuit for forced-air cooling operation of refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a forced cooling operation control circuit that forcibly cools a refrigerator as desired.

In general, forced cooling control of a refrigerator, which performs forced cooling by continuously operating a compressor using a forced cooling switch, performs cooling operation for a certain period of time regardless of the ambient temperature of the refrigerator.

However, if you put hot food in the freezer and want to freeze it quickly, you can preserve it properly by letting it pass quickly through the ice crystal formation zone, but depending on the ambient temperature of the refrigerator, The times are different, slower for higher outside temperatures and earlier for lower outside temperatures, so
If forced cooling is performed for a fixed period of time regardless of the ambient temperature, which takes different times to reach the appropriate freezing temperature, the freezing chamber becomes too cold and electricity is wasted.

Therefore, the present invention detects the ambient temperature of the refrigerator, changes the forced cooling operation time according to the ambient temperature, and shortens it when the outside temperature is low, thereby performing forced cooling without using unnecessary power. .

An embodiment of the present invention will be described below.

1 is an internal temperature detection circuit, which includes a comparator 2, a resistor R1,
It consists of R2, R3 and thermistor THl.

The resistors R2 and R3 are connected and the resistors R2 and R3 are connected to each other.
It is also connected to human power. In addition, the resistor R1 and thermistor T-Hl are connected, and also connected to the individual inputs of the resistor comparator 2.The output of the resistor comparator 2 is connected to the single input of the OR circuit 3, and the output is the output of the transistor 4. It is connected to a base resistor R4.A relay 6 is connected to the collector of the transistor 4, and the other end of the relay 5 is connected to V.0.The emitter of the transistor 4 is connected to GND. Normally open contact 6 of relay 6
is connected to one end of the AC power source 8 and the compressor 7, and the other end of the compressor 7 is connected to the AC power source 8. 9 is an outside temperature detection circuit, which has a controller (rater 1° resistor R6, R
6, R7 and thermistor TH2. Resistors R6, R7 and the controller (connected to one of the resistors 1o, resistor R6, thermistor TH2 and comparator 10
The other ends of the resistors R5 and R6 are connected to the respective inputs of V. The other ends of the C power supply, thermistor TH2, and resistor R7 are connected to GND.

The output of the comparator 10 is connected to the base resistor R8 of the transistor 12. The lid of the transistor 12 is connected to a capacitor C2 and connected to GND.

Reference numeral 11 denotes an oscillation circuit that performs charging and discharging with a time constant determined by a resistor R9 and capacitors C1 and C2, and generates a pulse serving as a clock signal at its output. The clock terminal of this oscillation circuit 11 is connected to the resistor R9 and capacitors C1 and C2, respectively. And the other end of resistor R9 is v
o. The power supply and the bell end of capacitor C1 are connected to GND. 13 is a timer, which is a flip-flop circuit FF1. F
It is composed of F2...FFy, and each Q output is connected to a clock input. Also, the Q output and data input are connected respectively. It is connected to the input of the timer 130, that is, the clock input of the 7-rip 70-tub circuit FF1 and the Q output of the oscillation circuit 11.

14 is a switch for forced cooling, one end of which is set to V. . power supply and
The other end is connected to the clock input of the resistor R1° flip-flop circuit 16. And the other end of the resistor R1゜ is GN
D is connected. 6 of the flip-flop circuits 16
The output and data input are connected, and the Q output is the reset terminal of the oscillation circuit 11, the inputs of the OR circuit 3, the AND circuit 16,
They are connected to the base resistor R11 of the transistor 18, respectively.

The inputs of the AND circuit 16 are connected to the final stage output of the timer 13, that is, the six outputs of the flip-flop circuit FF7, and the output of the AND circuit 16 is connected to the input of the one-shot circuit 17. The output of the one-shot circuit 17 is sent to each flip-flop circuit FF1 . FF2...
... are connected to the reset terminal of FF7 and the reset terminal of flip-flop circuit 16, respectively.

The collector of the transistor 18 is connected to an indicator 19 during strong cooling via a resistance R12. The other end of the display 19 is connected to the vCc power source. The emitter of transistor 18 is connected to GND. FIG. 2 shows changes in temperature inside the refrigerator after forced cooling operation under different outside temperatures. The temperature inside the refrigerator will drop faster when the outside temperature is low than when the outside temperature is high.

Next, the operation of the circuit configured as described above will be explained. Place thermistor TH1 in the freezer compartment of the refrigerator, and place thermistor TH2 in the freezer compartment of the refrigerator.
are placed outside the refrigerator. The thermistor TH1 placed inside the refrigerator has a small resistance value when the temperature is high, and the potential at point B is lower than the potential at point A, so the output of comparator 2 is "1".The output of comparator 2 is 1'. ', the power of one person in OR circuit 3 is 61'
Therefore, the output will be 1" regardless of the state of the individual inputs,
Transistor 4 is turned on via base resistor R4, and relay 6 is energized. The normally open contact 6 of this relay 6 is closed to connect the AC power source 8 to the compressor 7, and the compressor 7 starts to cool the inside of the refrigerator through a refrigeration cycle. Comple? When the temperature inside the refrigerator decreases due to the operation in step 7, the resistance of the thermistor TH1 gradually increases.
When the temperature inside the refrigerator becomes lower than the set value, the resistance of the thermistor TH1 increases, and the potential at point B becomes higher than the potential at point A, and the output of comparator 2 becomes 0". When the output of comparator 2 becomes 0", OR circuit 3 The power of one person is "o". At this time, if the Q output of the flip-flop circuit 16 is "o", both inputs of the OR circuit 3 become "101", the transistor 4 is turned off, and the relay 5 stops operating. When the relay 6 stops operating, the normally open contact 6 is opened, and the compressor 7 is disconnected from the AC power source 8 and stops operating. As a result, the cooling operation is stopped, the temperature inside the refrigerator gradually increases, and the resistance of the thermistor TH1 decreases. When the temperature inside the refrigerator becomes high and exceeds the set value, the thermistor TH
With a resistance value of 1, the potential at point pB becomes lower than the potential at point A, the output of comparator 2 becomes 1'', and compressor 7 starts cooling operation as described above.

In this way, the compressor 7 is repeatedly operated and stopped by the thermistor TH1.

Then, thermistor TH2, which detects the outside temperature,
The point potential is low, and the output of the comparator 10 is 1.
”, and the thermistor TH2 is below 20℃.
If detected, the potential at point C is higher than the potential at point D, and the comparator 10 operates so that the output becomes 0''.

For example, if the outside temperature is 20°C, the output of the comparator 10 is 1'' as described above, the transistor 12 is turned on, and the clock pulse of the oscillation circuit 11 is generated by the resistor R9 and the capacitor (C102). However, if the reset terminal of the oscillation circuit 11 is "o", the oscillation is stopped.

Therefore, when the forced cooling switch 14 is activated and turned on, the flip-flop circuit 16 operates and the Q output changes from 0'' to 1''. The forced cooling switch 14 is a switch that operates to be in an on state only during suppression, and to be in an off state when suppression is stopped.

When forced cooling is commanded by suppressing the forced cooling switch 14, the Q output of the flip-flop circuit 16 becomes 1'', and the single power of the OR circuit 3 becomes '1''. Therefore, the output of the OR circuit 3 becomes 61", and as described above, the compressor 7 operates due to the operation of the transistor 4, and cooling operation starts. When the Q output of the flip-flop circuit 16 becomes "1", the transistor 18 turns on. , the indicator 19 during strong cooling lights up to indicate that strong cooling is in progress.

At the same time, the reset terminal of the oscillation circuit 11 is set to "1".
This results in an oscillation state.

Since the outside temperature is 20° C. or higher, the circuit oscillates with the time constant determined by the resistor R9 capacitor (C1+02) as described above, and outputs a pulse from the Q output. The timer 13 is the Q of the oscillation circuit 11.
Input pulses from the output and count the pulses. When the counting operation progresses and T1 time elapses, the timer 13
That is, the 6 outputs of flip-flop circuit FFy are
1”.

When the 6th output/power of the flip-flop circuit FF7 becomes "0", the output of one person in the AND circuit 16 becomes 1' and the other person's power becomes 60'', and the output changes from 1 to 0. In response to this change in signal, the output changes from 1 to 0. The circuit 17 operates and outputs one positive pulse.The pulse of the one-shot circuit 17 causes the timer 1 to start.
3-7 lip-flop circuit FF1. FF2...
A reset signal is sent to each reset terminal of FF7 and flip-flop circuit 16, and the count number of timer 13 is set to 0.
Reset to .

The flip-flop circuit 16 is also reset, and the Q output is 1.
The value changes from "0" to "0", and the forced cooling operation is stopped.

When the Q output of the flip-flop circuit 15 becomes 0'', the transistor 18 is turned off and the display 19, which is being strongly cooled, goes out.At the same time, the reset terminal of the oscillation circuit 11 becomes 0'' and stops oscillation. Furthermore, the single-man power of the OR circuit 3 becomes "0". Since the interior of the refrigerator is sufficiently cooled by the forced cooling operation, the output of comparator 2 is in the state of "0", and both the two inputs of OR circuit 3 are in the state of 0", the output becomes '0', and transistor 4 is turned off. , the normally open contact 6 of the relay 16 is opened, the compressor 7 is disconnected from the AC power source 8,
Stop operation. This allows the forced cooling operation to be performed at an outside temperature of 20°C.
'C or more, the process will end after T1 time has elapsed.

The time is calculated from x127.

Next, a case where the outside air temperature is 20° C. or lower will be explained.

When the outside temperature is below 20°C, the output of the converter 10 becomes "O" and the transistor 12 is turned off. Therefore, the oscillation circuit 11's current is determined by the resistor R9 and the capacitor C1. It becomes a constant pulse. When the forced cooling switch 14 is activated and forced cooling operation is commanded, the compressor 7 operates as described above and performs cooling operation) #, grin*, +O*ys□ f5.9
-Yo 10, Ya 6. Ah.

Show that. Also, the reset terminal of the oscillation circuit 11 is “1”.
”, a pulse with a time constant determined by the resistor R9 and the capacitor C1 is output, and the timer 13 counts this pulse. When the count progresses and reaches 12 hours, the final stage output of the timer 13, that is, the output of the flipflop circuit FF7. 6 Output changes from ``1'' to ``0'' Ma 13 resets the count to 0,
The compressor 7 stops, the intense cooling indicator 19 turns off, and the forced cooling operation ends. From then on, the compressor operation and stop are controlled according to the output of the comparator 2 operated by the thermistor TH1 that detects the temperature inside the refrigerator. Ru.

The forced cooling operation time T2 when the outside temperature is 20℃ or less is determined by the resistance R and...
~delsuC, and is the time calculated from TR9xC19121,46x127. Therefore, the outside temperature is 20
The relationship between T1 time above °C and 12 hours below 20 °C is T1>T2, and the forced cooling operation is long when the outside temperature is high, and shortened when the outside temperature is low, making it a two-step control. . Furthermore, when the forced cooling switch 14 is operated during the forced cooling operation, the Q output of the 7-lip flow soap circuit 16 changes from 1'' to 0'', and the forced cooling operation is stopped as described above. Therefore, the forced cooling operation can also be stopped manually.

As described above, according to the present invention, the forced cooling operation is performed by operating the switch, and the forced cooling time is arbitrarily controlled according to the ambient temperature of the refrigerator. 75) Since the cooling operation is performed for a certain period of time regardless of the temperature, food is cooled quickly when the outside temperature is low, and even if the temperature reaches the appropriate storage temperature, the cooling operation is still performed, resulting in wasted electricity due to unnecessary cooling operation. It has great effects, such as eliminating the drawbacks and being able to implement it at a lower cost.

[Brief explanation of the drawing]

FIG. 1 is an electrical wiring diagram showing a strong cooling operation control circuit of a refrigerator according to an embodiment of the present invention, and FIG. 2 is a diagram showing temperature changes inside the refrigerator during forced cooling operation. TH1...-Thermistor, 7...-Conc 0 Resosa, TR2...Thermistor, 11...
・Oscillation circuit, 13... Timer, 14...
・Switch for forced cooling.

Claims (1)

[Claims] A compressor that cools the inside of the refrigerator, a thermistor that detects the temperature inside and outside the refrigerator, a timer consisting of a flip-flop circuit, an oscillation circuit that can switch in multiple stages to change the operating time of the timer, and a compressor that forces the compressor to operate. the compressor is forcibly operated by the switch, a timer is operated by the pulse of the oscillation circuit, and the operation is stopped by the output of the switch or the timer; A forced cooling operation control circuit for a refrigerator that changes the operating time by increasing or decreasing the pulses of the oscillation circuit using a thermistor that detects outside air temperature.