JPS63290369A - Air conditioner - 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] [Object of the Invention] (Industrial Application Field) This invention relates to an air conditioner, and particularly to an air conditioner that can defrost an outdoor heat exchanger while continuing heating operation. Regarding.

(Prior art) As shown in Fig. 4, a general air conditioner has a compression unit 11a, a four-way valve b, an indoor heat exchanger C, an expansion valve d, and an outdoor heat exchanger e connected in sequence through a refrigerant line. to configure the refrigeration cycle.

This refrigeration cycle enables cooling/heating cycle operation by switching the four-way valve to reverse or reverse the flow of refrigerant.

During the defrost cycle operation, high-temperature refrigerant is sent to the outdoor heat exchanger e by switching the four-way valve to the cooling cycle operation position, and defrosting is performed. Since low-temperature refrigerant will flow into container C, the indoor fan is set to 0 [F] to prevent cold air from being blown into the room. However, at this time, low-temperature refrigerant is sent to the indoor heat exchanger, so heat loss of about 100 to 200 cal/h occurs due to natural convection, and when switching between four-way valves, high-pressure refrigerant Because the pressure balance with the low-pressure refrigerant occurs instantaneously, problems such as refrigerant noise occur.

Therefore, an air conditioner as shown in FIG. 5 has been developed.

As shown in the figure, this air conditioner has a compression tjl
In a basic refrigeration cycle f consisting of al, four-way valve b1, outdoor heat exchanger e1, expansion valve d1, and indoor heat exchanger C1, the refrigerant line q between the outdoor heat exchanger e1 and the expansion valve d1, and the compression tfi a The refrigerant line h connecting the + discharge side and the four-way valve b1 is connected by a bypass line i, and the bypass line i is provided with an on-off valve j for opening and closing the line.

In other words, this proposal leaves the four-way valve in the heating cycle operating position during defrosting operation, and then asks the valve to open at this time to bypass and send high-temperature, high-pressure refrigerant to the outdoor heat exchanger. This makes it possible to defrost the outdoor heat exchanger,
It is also designed to reduce refrigerant noise.

(Problem to be solved by the invention) However, the configuration in which high-temperature, high-pressure refrigerant is bypassed to the outdoor heat exchanger during snow removal means that the outdoor heat exchanger absorbs no heat from the outdoor air at this time. Since the heating capacity is lost, the heating capacity of the outdoor heat exchanger is essentially lost, and the drawback that the room temperature drops significantly during that time remains.

[Structure of the Invention] (Means for Solving Problems) This invention connects a compressor, a four-way valve, an indoor heat exchanger, and an expansion valve in sequence with a refrigerant line, and connects a refrigerant line between the four-way valve and the expansion valve. A branch line is formed in which first and second outdoor heat exchangers are interposed in parallel, and a bypass line connected to the refrigerant line between the discharge side of the compressor and the four-way valve is connected to the expansion valve and the first and second outdoor heat exchangers. The problem is solved by configuring an air conditioner that is connected to the branch lines between two outdoor heat exchangers, and each of the bypass lines is provided with an on-off valve that is switched to open and close during heating operation and defrosting operation. It was used as a last resort to solve the problem.

(Function) During heating operation and defrosting operation, for example, first the on-off valve on the first outdoor heat exchanger side is opened, and the on-off valve on the second outdoor heat exchanger side is opened. Therefore, the high-temperature, high-pressure refrigerant compressed by the compressor is first sent to the first outdoor heat exchanger to melt the frost that has accumulated on the first outdoor heat exchanger. At this time, the second outdoor heat exchanger is still continuing the heating operation, so it absorbs heat from the outdoor air. When the defrosting of the first outdoor heat exchanger ends, the on-off valve on the first outdoor heat exchanger side is switched to closed, and at the same time, the on-off valve on the second outdoor heat exchanger side is opened, so that the second outdoor heat exchanger The exchanger is defrosted. At this time, the first outdoor heat exchanger continues the heating operation.

In this way, the defrosting operation is performed without supplying cold air indoors during the heating operation.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

In Fig. 1, poly 1 is a compressor that sucks in refrigerant, compresses it, and discharges it, 2 is a four-way valve that switches the flow of refrigerant, 3 is an indoor heat exchanger, and 4 is an expansion valve.

In this embodiment, the outdoor heat exchanger consists of a first outdoor heat exchanger 5 and a second outdoor heat exchanger 6, and a branch line 7 provided in parallel with the refrigerant line 14 between the four-way valve 2 and the expansion valve 4. ．．
8 respectively. A throttle device 9.10 is provided immediately downstream of the first and second outdoor heat exchangers 5.6 (on the expansion valve 4 side), respectively.

On the other hand, the refrigerant line 12 connecting the discharge port 11 of the compressor 1 and the four-way valve 2 is branched into a branch line 7.8 between the expansion device 9.10 and the first and second outdoor heat exchangers 5 and 6. The other end of the bypass line 15 and 16 connected to each other is connected. Each branched bypass line 15.16 is provided with an on-off valve 17.18 that opens and closes the line, respectively.

To explain the other refrigerant lines, the suction port 11 of the compressor 1 and the four-way valve 4 are the refrigerant line 20, the four-way valve 2 and the indoor heat exchanger 3 are the refrigerant line 21, and the indoor heat exchanger 3 and the expansion valve are the refrigerant line 20. 4 are connected by a refrigerant line 22.

The refrigeration cycle 23 configured as described above, excluding the indoor heat exchanger 3, is assembled into an outdoor unit 24 as shown in FIG. 2. That is, on one side 25 of the outdoor unit 24, a first outdoor heat exchanger 5 and a second outdoor heat exchanger 6 are installed vertically in parallel, and on the other side 26, the first and second outdoor heat exchangers 5 are installed.
．． Fan motor 27.28 that sends air to 6 separately
An inverter device 29 is provided above the outdoor unit 24.
And the four-way valve 4 is fixed with the compression valve 1 disposed below.

Next, the control contents of the refrigeration cycle will be explained based on FIG. 3, and this control contents are performed by a controller not shown.

First, considering the capacities of the first and second outdoor heat exchangers 5.6, in the next judgment 30, for example, approximately 40 minutes have passed after the start of heating operation or the start of defrosting operation, and the first and second outdoor heat exchangers 5.6 Temperature Te<-8 detected in each of the second outdoor heat exchangers 5.6
Determine whether the temperature is ℃. If the determination 30 is YES, step 31 of starting defrosting operation is executed. If NO, the heating operation continues.

Here, in step 31, the compressor 1 is turned on, the fan motor 27 is turned off, the four-way valve 2 is switched to the heating position, the switching valve 18 is opened, and the switching valve 17 is opened.

Then, only the first outdoor heat exchanger 5 is defrosted. That is, the high-temperature, high-pressure discharged refrigerant is sent to the first outdoor heat exchanger 5 to melt the frost attached to the first outdoor heat exchanger 5. During this time, the second outdoor heat exchanger 6 is used as an evaporator, so it continues to absorb heat from the outside. In other words, the room is heated.

After executing step 31, the elapsed time is checked at decision 32. That is, it is determined whether 5 minutes have elapsed, for example, and if these values are Y[S, the defrosting switching step 32 is executed.

If NO, time is measured again. In step 33, the compression mode 1 is turned on, the fan motor 27 is turned on, the fan motor 28 is turned off, the four-way valve 2 is at the heating position, the on-off valve 17 is opened, and the open/close valve 18 is closed. Then, the second outdoor heat exchanger 6
Only defrosting is performed. That is, the discharged refrigerant at tS temperature and high pressure is sent to the second outdoor heat exchanger 6 to melt the frost attached to the second outdoor heat exchanger 6. During this time, the first outdoor heat exchanger 5 functions as an evaporator and continues to absorb heat from the outdoor air. That is, the room is still heated. When step 33 is completed, the elapsed time is measured again in judgment 34. That is, it is determined whether 5 minutes have passed and if Y[S, the process returns to judgment 30 and measures whether 40 minutes have passed after the start of heating or the start of defrosting. Here, if Te is <-8° C. in judgment 30, the flow is instructed to be repeated again.

By the way, the reason why the first and second outdoor heat exchangers 5 and 6 are arranged above and below the outdoor unit 24 and the upper first outdoor heat exchanger 5 is defrosted first is that Assuming that the water that is defrosted in the outdoor heat exchanger 5 and thus melted will form frost on the second outdoor heat exchanger 6 again, the amount of the neck frost is
This is to melt it when defrosting the outdoor heat exchanger 6, but if it is arranged in the width direction of the outdoor unit 24, it does not matter which one comes first. Furthermore, if the total capacity of the first and second outdoor heat exchangers 5.6 is lower than that of a refrigeration cycle employing one outdoor heat exchanger, it is necessary to increase the capacity of compression mode 1. . In the embodiment, the power for the compressor 1 is taken from the inverter device 29, and the frequency of the inverter device 29 is increased so as to increase the rotation speed of the compressor 1 during defrosting. For example, from 50Hz to 100
Upload to 11z or higher.

Although the heating operation has been explained above, the cooling operation is performed by switching the four-way valve 2 to the cooling position, and the refrigerant flows from the first and second outdoor heat exchanger 5.6 side to the indoor heat exchanger 3 side, Cools the room by absorbing heat from the indoor air. Open/close valve 17.18
are all closed. However, the temperature Te of the first and second outdoor heat exchangers 5.6 can be determined by a temperature sensor such as a thermistor (not shown), and the detected temperature is input to the controller.

(Effects of the Invention) As is clear from the above explanation, according to the present invention, it is possible to defrost the outdoor heat exchanger with the minimum necessary amount of heat while continuing the heating operation, and the defrosting time It has the excellent effect of shortening the time.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a preferred embodiment of the present invention, FIG. 2 is a schematic perspective view of the outdoor unit, FIG. 3 is a flowchart of the heating operation of the refrigeration cycle shown in FIG. 1, and FIG.
The figure is a system diagram of a general air conditioner, and FIG. 5 is a system diagram of an air conditioner as related technology. In the figure, 1 is a compressor, 2 is a four-way valve, 3 is an indoor heat exchanger, 4
1 is an expansion valve, 5 is a first outdoor heat exchanger, 6 is a second outdoor heat exchanger, 7 and 8 are branch lines, 9 and 10 are throttle devices, 1
5 and 16 are bypass lines, and 18 and 19 are on-off valves. Patent applicant: Toshiba Corporation Patent attorney Nobuo Kinutani Figure 1 Figure 2

Claims (1)

[Claims] A branch line in which a compressor, a four-way valve, an indoor heat exchanger, and an expansion valve are sequentially connected through a refrigerant line, and a first and second outdoor heat exchanger are interposed in parallel in the refrigerant line between the four-way valve and the expansion valve. A bypass line connected to the refrigerant line between the discharge side of the compressor and the four-way valve is connected to the branch line between the expansion valve and the first and second outdoor heat exchangers, and the bypass line is connected to the refrigerant line between the discharge side of the compressor and the four-way valve. An air conditioner, each of which is provided with an on-off valve that is switched open and closed during heating operation and defrosting operation.