JPS60251335A - Control device for defrosting of heat pump type air-conditioning machine - Google Patents

Abstract

PURPOSE:To reduce a difference between a room temperature, reduced by defrosting operation, and a set temperature and prevent the provision of feeling of cold airflow by a method wherein a defrosting signal is reset and room heating operation is effected again when the room temperature has arrived at a temperature lower than the set temperature, reset at a predetermined lower temperature, by a differential. CONSTITUTION:When defrosting signal B is outputted from a defrosting signal generating circuit 5 at the point of time T3 soon after the operation of a compressor is restored, the set temperature (a) is changed to another set temperature (b), having a difference of predetermined temperature (t), and the differential (a') is extremely reduced to another differential (b'). At the same time, the defrosting signal B puts a four-way valve driving relay 10 ON through a driver 9 and the four-way valve is switched. Accordingly, the defrosting operation is effected from the point of time T3 to the point of time T4. Then, the output of a comparator 3 or compressor ON/OFF signal A becomes H at the point of time T4, the output of a reset circuit 11 or reset signal C is inputted into the defrosting signal generating circuit 5 and the defrosting signal B becomes L. Accordingly, the four-way valve is put OFF, the set temperature is returned to the set temperature (a), the differential is also returned to the differential (a') and the room cooling operation may be restored.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a defrosting control device for a heat pump type air conditioner, and particularly to a control circuit for preventing a drop in room temperature due to defrosting operation.

Conventional configuration and its problems In the conventional defrost control device of a heat pump air conditioner, when the defrost signal turns ON during heating operation, the four-way valve immediately switches (from OFF state to ON state) and compresses the air conditioner. The machine operates continuously to perform defrosting operation. Therefore, if the defrost signal is turned on soon after the compressor is turned on while the compressor is operating at 0N10FF with a predetermined differential, the difference between the set temperature and the room temperature will become significant due to the room temperature drop due to the defrost operation. It had the disadvantage of giving a feeling of cold air.

OBJECT OF THE INVENTION Therefore, an object of the present invention is to reduce the difference between the room temperature, which decreases due to defrosting operation, and the set temperature, thereby preventing the feeling of cold air.

Structure of the Invention In order to achieve this object, the present invention includes a room temperature detection means for detecting the indoor temperature, a room temperature setting means for setting the room temperature to a desired temperature, and a temperature detected by the room temperature detection means and a set temperature by the room temperature setting means. a comparator that controls the compressor at 0N10FF by comparing the values of and a defrost signal generation circuit that lowers the set temperature of the room temperature setting means by a predetermined temperature using the defrost signal and reduces the differential of the differential circuit, and receives the comparator output signal and the defrost signal as inputs. A reset circuit that resets the defrosting signal to restore heating operation when the room temperature reaches a temperature lower than the set temperature by a predetermined amount by a differential amount, and shortens the predetermined integrated operation time of the defrost signal generation circuit by a predetermined time. By configuring the defrost control device from
In other words, the defrosting operation is stopped before the temperature reaches a point where it feels cold, and the heating operation is resumed. Residual frost is dealt with by shortening the time until the next defrost. This is to prevent the decline.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. 1st
The figure is a block diagram of a defrosting control device, and numeral 1 indicates room temperature detection means such as a thermistor for detecting room temperature. Reference numeral 2 denotes a room temperature setting means composed of a variable resistor or the like for setting the room temperature to a desired temperature, and the set temperature can be changed by the defrosting signal B. 3 compares the temperature detected by the room temperature setting means 1 and the temperature set by the room temperature setting means 2 and sets the compressor (not shown) to 0N.
10FF This is a comparator that outputs signal A. Reference numeral 4 denotes a differential circuit for determining the differential of the comparator 3, and is configured to be able to switch the differential in response to the defrosting signal B. Reference numeral 6 denotes a defrosting signal generation circuit which integrates the operating time during heating operation and outputs a defrosting signal B when a predetermined time is reached, and the defrosting signal B is inputted to the room temperature setting means 2 and the differential circuit 4 as an external signal. 6 is an O that inputs the compressor's 0N10FF signal A and the defrosting signal B.
The output of the R circuit is connected to a compressor drive relay 8 via a driver 7. Further, the defrosting signal B is connected to a four-way valve driving relay 10 via a driver 9. 11 inputs the compressor 0N10FF signal A and the defrost signal B, connects the output to the defrost signal generation circuit 5, resets the defrost signal B, restores the heating operation, and also outputs the predetermined signal in the defrost signal generation circuit 5. This is a reset circuit that shortens the cumulative operating time by a predetermined amount of time.

This reset circuit 11 has an internal configuration of the compressor 0N1.
It consists of a delay circuit 12-1 which receives the 0FF signal A and delays it by a slight time, and an AND circuit 13 which inputs the defrosting signal B and the output signal of the delay circuit 12 by hand.

In the above configuration, refer to the time chart diagram in Figure 2.
Explain the operation. During heating operation, when the room temperature detected by the room temperature detection means 2 is lower than the set temperature a set by the room temperature setting means 2, the output of the comparator 3 is 0N10 F of the compressor.
F signal A becomes logic level "H'". Therefore, OR
The output of the circuit 6 also becomes H'', the compressor drive relay is turned on via the driver 7, and the compressor is driven.
When the room temperature reaches the set temperature a at point 1, the compressor 0N10FF signal A, which is the output of the comparator 3, becomes "L" at the logic level.
At the same time, the output of the OR circuit 6 also becomes "L". Therefore, the compressor drive relay 8 is turned off and the compressor stops operating. Also, the room temperature decreases, and at the point of 120, the room temperature reaches the set temperature. When the temperature reaches a temperature lower than a by the differential a', the compressor 0N10FF signal A, which is the output of the comparator 3, is again
becomes H#, and the compressor drive relay 8 is turned on as before.
L, compressor is driven.

Shortly after the compressor returns to operation, the defrost signal B is output from the defrost signal generation circuit 5 at time T3 (when it is H, the set temperature a changes to b, which is lower than the predetermined temperature, and the differential a'
also changes to an extremely small value b'. Therefore, since the room temperature is the set temperature, the compressor 0N10FF signal A, which is the output of the comparator 3, is at +4 time tll'' when the differential air temperature reaches the lower temperature.However, the defrost signal B is OR
Since circuit 6 is powered by one person, the output of OR circuit 6 is +1
) (II, the compressor drive relay 8 is turned ON via the driver 7, and the compressor continues to operate. Also, the defrost signal B
turns on the four-way valve drive relay 10 via the driver 9, and the four-way valve (not shown) is switched. Therefore, the defrosting operation will be performed from +3 to +4. Then, at the time of +4, the compressor 0N10FF signal A, which is the output of the comparator 3, becomes +1)('' and is input to the AND circuit 13 via the delay circuit 12 of the reset circuit 11. Defrost signal B, defrost signal B also +1 HIT
Therefore, the output of the AND circuit 13 becomes a Hn. A
The reset signal C, which is the output of the ND circuit 13, that is, the output of the reset circuit 11, is input to the defrost signal generation circuit 5, the defrost signal generation circuit 5 is reset, and the defrost signal B is reset to I'L''. Therefore, Four-way valve drive relay 10
is OFF, the four-way valve is OFF L, and the reset signal C of the reset circuit 11 is l1ljl, the set temperature is returned to a, the differential is also returned to a', and the compressor, which is the output of comparator 3, is turned ON/○FF. Signal A is II
H# and returns to heating operation 0 The reset signal C of the reset circuit 11 is a timer included in the defrosting signal generation circuit 6, which integrates the operating time and outputs the defrosting signal B when a predetermined time is reached. The timer setting time is shortened by a predetermined amount of time, thereby shortening the interval before the next defrosting starts. Therefore, even if residual frost occurs by forcibly returning to heating operation depending on the room temperature, frost will not accumulate by shortening the interval until the next defrosting.

Note that the delay circuit 12 of the reset circuit 11 is for slightly delaying the output A of the comparator 3, but when the output A of the comparator 3 is H'', the defrosting signal B becomes lH)''. This is because when the output A of the comparator 3 changes from 1P to Ln, the output C of the AND circuit 13 will become H'' unless the time delay is delayed.

Effects of the Invention As is clear from the above description, the present invention includes a room temperature detection means for detecting the indoor temperature, a room temperature setting means for setting the room temperature to a desired temperature, and a temperature detected by the room temperature detection means and a room temperature setting means. Compare the set temperature and set the compressor to 0N10F.
A comparator that performs F control, a differential circuit that determines the differential of the comparator, and a differential circuit that integrates the operating time during heating operation and outputs a defrosting signal when a predetermined time is reached to control the defrosting operation, and also controls the defrosting operation. The set temperature of the room temperature setting means is lowered by a predetermined temperature, and the defrost signal generating circuit that extremely reduces the differential of the differential circuit, and the comparator output signal and the defrost signal are inputted so that the room temperature is set to a predetermined temperature. a reset circuit that resets the defrosting signal to restore the heating operation when the temperature reaches a temperature lower than the set temperature by a differential amount, and shortens a predetermined cumulative operation time of the defrosting signal generating circuit by a predetermined time; Therefore, when the room temperature drops due to the defrosting operation, the heating operation is forcibly returned to the temperature at which the user feels a feeling of cold air, thereby preventing the room temperature from falling and giving no feeling of cold air. Also, when forcibly discontinuing defrosting, use 4
This can be prevented by shortening the defrosting interval to prevent frost buildup. However, this does not apply when the amount of frost is small and the defrosting process is completed when the room temperature is higher than the predetermined temperature.

[Brief explanation of the drawing]

FIG. 1 is a circuit block diagram showing an embodiment of the defrosting control device for a heat pump type air conditioner according to the present invention, and FIG. 2 is an operation time chart. 1...Room temperature detection means, 2...Room temperature setting means, 3...Comparator, 4...Differential circuit, 6...Defrosting signal generation Circuit, 11...
...Reset circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] a room temperature detection means for detecting the indoor temperature; a room temperature setting means for setting the room temperature to a desired temperature; and a comparator for controlling the compressor to 0N10FF by comparing the temperature detected by the room temperature detection means and the set temperature by the room temperature setting means. , a differential circuit that determines the differential of the comparator, and a defrosting signal that integrates the operating time during heating operation and when a predetermined time is reached, controls the defrosting operation, and also controls the room temperature based on the defrosting signal. Lower the set temperature of the setting means by a predetermined temperature,
The defrost signal generation circuit that reduces the differential of the differential circuit, the comparison output signal, and the defrost signal are set to υJ, and when the room temperature reaches a temperature lower by the differential amount than the set temperature lowered by a predetermined temperature, the defrost signal is generated. A defrosting control device for a heat pump type air conditioner, comprising a set circuit for resetting a heating operation by resetting the defrosting signal generating circuit and shortening a predetermined cumulative operation time of the defrosting signal generating circuit by a predetermined period of time.