JPS5843669B2 - air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control method for an air conditioner, and an object of the present invention is to make it legal and rational to use a heat pump type air-conditioning device during heating.

Figure 1 is a diagram showing the basic configuration of a separate heat pump air conditioning system, in which 1 is an indoor unit, 2 is an outdoor unit, 3 is a compressor, 4 is a four-way valve that switches the direction of refrigerant,
5 is an outdoor heat exchanger (evaporator for heating, condenser for cooling)
6 is a fan motor for the outdoor heat exchanger, 7 is a heating throttle valve,
8 is a check valve for cooling.

9 is an indoor heat exchanger (condenser for heating, evaporator for cooling)
, 10 is a fan motor for an indoor heat exchanger, 11 is a cooling throttle valve, 12 is a heating check valve, and 13 is an auxiliary heater for heating.

Reference numeral 14 indicates an indoor temperature sensor provided at the indoor air intake port of the indoor unit, and reference numeral 15 indicates an indoor temperature sensor that controls ON/OFF of the compressor 3 button and the auxiliary heater 13 based on its output.

The figure shows the heating mode, and the refrigerant coming out of the compressor 3 passes through the four-way valve 4 and is condensed in the indoor heat exchanger 9.
2, the pressure is reduced by the heating throttle valve 7, and the outdoor heat exchanger 5
It evaporates and returns to the compressor 3 through the four-way valve 4.

The indoor temperature detector 14 detects the temperature of the indoor air sucked in by the indoor fan motor 10 and sends its output to the controller 1.
5 to control the compressor 3 button and the auxiliary heater 13 on and off.

By the way, the above-mentioned air conditioning system is equipped with a defrost timer to prevent frost formation on the outdoor heat exchanger 5 during heating operation, and after heating operation for a certain period of time, for example, 60 minutes, the four-way valve 4 is turned off.
The operation is repeated by switching to the cooling cycle and performing defrosting operation for a certain period of time, for example, 10 minutes.

During this defrosting operation, the indoor fan motor 10 is temporarily stopped to prevent cold air from blowing into the room. However, as soon as the defrosting operation returns to heating operation, the indoor fan motor 1
0 is activated, cold air is blown into the room, creating a so-called cold draft, which causes discomfort to the occupants.

This cold draft similarly occurs immediately after starting heating operation.

The present invention is intended to eliminate the above-mentioned drawbacks, and includes a defrost timer that is reset when the power is turned on and when the defrost operation ends, and the four-way valve 4 is switched by the timer, and the timer After a predetermined time has elapsed after the reset, that is, the temperature of the indoor heat exchanger 9 is a certain temperature!
and then the indoor fan motor 10
This is intended to prevent the occurrence of the cold draft.

``An embodiment of the invention will be described with reference to FIG.

In the same figure, the button 16 is an air conditioning/heating changeover switch, which has a heating contact a and a cooling contact A, and the heating contact a is closed in the figure.

The parallel circuit of the four-way valve 4, the defrost timer 17, and the indoor fan motor 10 controlled by the timer 17 is connected in series with this selector switch 16, and the compressor 3, the outdoor fan motor 6 button, and the auxiliary heater are connected in series. 13, power supply 1
8 in parallel.

19 is a power switch, and 20a, 20b, 20c are relay contacts that are opened and closed by a timer 17.

Next, its operation will be explained with reference to the time chart shown in FIG.

1. When the power switch 19 is turned on at time T1, the compressor 3, outdoor fan motor 6, and auxiliary heater 13 are turned on by the power supply 1.
8 and turns on, heating operation starts.

At this time, relay contacts 20a open and button, 20b, 2
0c are both closed.

Timer 17 is activated at time T2 after a predetermined period of time (time at which cold draft occurs or occurs) after the power is turned on.
closes the contact 20a, and the indoor fan motor 10 starts one drive.

At time T3 when the temperature of the outdoor heat exchanger 5 has decreased to a certain temperature after a certain heating time has elapsed, the timer 17 switches the contact point 20a,
20b.

Open 20c and start defrosting operation.

When 20a is opened, the indoor fan motor 10 is stopped, and 20a is opened.
By opening b, the four-way valve 4 is switched to the cooling cycle, and the 2-way valve 4 is switched to the cooling cycle.
When 0c is opened, the outdoor fan motor button and the auxiliary heater 13 are stopped, and only the compressor 3 is driven.

At time T4 when the temperature of the outdoor heat exchanger 5 rises to a certain temperature after a certain defrosting time has passed, the tie 17 contacts the contact point 20b.

20c is closed to enter heating operation, and the timer 17 is reset and starts counting, at time T5 when a certain period of time (the time when a cold draft occurs or is present) has elapsed.
The contact 20a is closed and the indoor fan motor 10 is driven to return to the normal heating state.

Time T6 is when the power switch 19 is turned off,
Time T7-T11 is a repetition of time T1-T5.

FIG. 4 is a diagram showing an example of a specific circuit of the defrosting timer 17.

21 is a DC power supply, 22 is a clock pulse generator, 23 is a counter, and 24a.

24b and 24c are relays that open and close the contacts 20a, 20b, and 20c.

When the power source 18 is turned on, the clock pulse generator 22 sends a pulse signal to the counter 23 .

The output states of the output terminals A, B, C, and D of the counter 23 change as shown in the truth table below.

When the power switch 19 is turned on at time T1, the count of the hexadecimal counter 23 is O, and its output terminals A, B, and C are
, D indicate an L (low) signal.

Therefore, transistor 25'? and 26 are all out of conduction, relay 24a opens contact 20a, and relays 24bi and 24c close contacts 20b:L" and 20c, and in this state heating operation is started.

When the count of the counter 23 reaches 1 at time T2, the D terminal of the counter 23 becomes H (high), the transistor 25 becomes conductive via the logic judgment circuit, and the relay 24a is energized, the contact 20a is closed, and the indoor fan motor is activated. 10 is activated and enters the regular heating state.

The time at time T3t- when defrosting is started is indicated by the counter 23.
This is the time at which the output terminals A, B, and C become H (high), and the count is 14.

That is, at count 14, the output i4 child A of counter 23
,B.

When C becomes H (high), the transistor 26 becomes conductive through the gate circuits E and r, the relays 24b and 24c are excited, and the contacts 20b i- and 20c are opened to start defrosting operation.

At this time, the transistor 25 becomes non-conductive due to the diode F, and the indoor fan motor 10 stops.

When the defrosting operation is completed, the output logic of the hexadecimal counter 23 returns to zero.

When the power switch 19 was turned on, the counter 2
3 is reset.

Therefore, the counter 23 starts from 0 count.

However, in the above embodiment, the indoor fan motor 10 is stopped during defrosting, but if it is necessary to detect the indoor temperature with the temperature sensor 14, the indoor fan motor 10 may be stopped instead of being stopped. It may be possible to rotate at a low speed that does not cause discomfort, and to rotate at full speed during regular heating.

In this case, the relay 24a switches between high-speed rotations.

The defrosting timer 17 of the present invention can freely adjust the heating operation time and the defrosting time by making the oscillation period of the clock pulse generator 22 variable.

Therefore, it is possible to set the appropriate heating time and defrosting time according to the environmental condition, which is much more rational than the conventional simple repeating switching method (60 minutes heating, 10 minutes defrosting). Moreover, unnecessary defrosting can be prevented.

Moreover, it is possible to add a slight time delay to the activation of the indoor fan motor without adding a timer for delaying the operation of the indoor fan motor.

In addition, since it is possible to switch between high-speed and low-speed rotation as appropriate, it is possible to prevent cold drafts that occur when starting heating or switching from defrosting to heating, making it possible to implement legal and rational methods for air conditioners. It has excellent effects when used on a regular basis.

[Brief explanation of the drawing]

Figure 1: A diagram showing one embodiment of a heat pump type air-conditioning device to which the present invention is applied, Figure 2; Figure 4 is a diagram showing one embodiment of the defrosting timer of the present invention. 1...Indoor unit, 2...Outdoor unit 3...
Compressor, 4... Four-way valve, 5... Outdoor heat exchanger, 6...
...Outdoor fan motor, 9...Indoor heat exchanger, 10.
...Indoor fan motor, 13...Auxiliary heater, 16.
・Air conditioning/heating selector switch, 17 ・Defrost timer 19
...Power switch, 20a, 20b, 20cm relay contact, 24a. 24b, 24c...Relay, 22...Clock pulse generator, 23...Counter, 25, 26...Transistor.

Claims (1)

[Claims] 1 Indoor heat exchanger, indoor fan motor, outdoor heat exchanger,
An outdoor fan motor, a compressor, a western valve that switches the direction of refrigerant, an N-ary counter whose output logic is initialized when the power is turned on and when defrosting is completed, and a gate circuit that determines the output logic of the N-ary counter. and a defrost timer for switching the four-way valve, a logic judgment circuit for determining logic is connected to the counter output of the defrost timer, and the output of the logic judgment circuit determines the An air conditioner characterized by controlling the drive of an indoor fan motor.