JPH03255860A - Cooling and heating inclusive type multi-chamber air conditioner - Google Patents

Abstract

PURPOSE:To obviate indoor unit side information and reduce signal transmission between an indoor unit and an outdoor unit by installing a high discharge pressure detector and a low suction pressure indicator to an outdoor unit and controlling the capacity of a compressor and the heat exchange capability of an outdoor heat exchanger in conformity with the deviation produced between a target high pressure and a target low pressure. CONSTITUTION:A discharge pressure detector 119 is installed on the way to a high pressure gas pipeline 109 of an outdoor unit 101 while a suction pressure detector 120 is installed on the way to a low pressure gas pipeline 111. When simultaneous operation is carried out with a single heat exchanger 112 serving in heating mode and three heat exchangers 113 to 115 serving in cooling mode, three vaporizers are required for a single condenser in terms of a refrigeration cycle, thus producing the above equipment ratio. As a result, both high pressure and lower pressure are deviated fro target values. At that time, an attempt is made to determine a capacity change variable of a compressor 103 and a heat exchange capability change variable of an outdoor heat exchanger 105, the variables of which are computed by a controller 108 in conformity with the deviation between a target high pressure and a detected value of the detector 119 and a target high pressure and a detected value of the detector 120.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an air conditioner capable of simultaneous cooling operation and heating operation.

[Conventional technology]

FIG. 3 shows a configuration diagram of a conventional multi-room air conditioning system disclosed in, for example, Japanese Unexamined Patent Application Publication No. 1-167561. In the figure, 1 is an outdoor unit, 2 is a compressor, and 3
is an outdoor heat exchanger, and 4 is an accumulator. 5a,
5b, 5c are three indoor units, 6a, 6b, 6c
7 is an indoor heat exchanger, 7 is a refrigerant discharge pipe, and 8 is a refrigerant suction pipe. 9a9b is a switching valve; 10 is inter-unit piping between the outdoor unit 1 and indoor units 53 to 5C;
12 is a high pressure gas pipe, 12 is a low pressure gas pipe, and 13 is a liquid pipe.

14a, -14b, 14c and 15a15b, 15c
are the switching valves 16a and 16b of each indoor unit 5a to 5C.
, 16c is a refrigerant pressure reducer, 17 is a bypass pipe, 20 is a refrigerant pressure reducer, and 22 is a fan of the outdoor heat exchanger 3.

Next, the operation will be explained. Here, indoor unit 5a
A case will be explained in which the unit and 5b are in the heating mode and the indoor unit/nod 5C is in the cooling mode. First, the high-temperature, high-pressure gas refrigerant discharged from the compressor 2 is guided to the indoor units z) 5a, 5b through the high-pressure gas pipe 11, and then the switching valves 14a, 14
b, is condensed and liquefied in heat exchangers 5a and 5b, and becomes a high-temperature liquid refrigerant.
After that, the high temperature liquid refrigerant is depressurized by refrigerant pressure reducers 16C and 20, and then divided into indoor unit 5C and outdoor unit 1, evaporated and gasified by heat exchangers 6C and 3, respectively, and switched to switching valves 15c and 9b. The gas then flows into the low pressure gas pipe 12. Thus, a refrigerant circuit is constructed in which the low-pressure gas refrigerant is sucked from the low-pressure gas pipe 12 through the accumulator 4 and into the compressor 112 again.

At this time, when controlling the outdoor unit 1, the compression 81
The capacity of 2 is determined according to the heating load of the indoor units 5a and 5b, and the speed or heat transfer area of the fan 22 of the outdoor heat exchanger 3 is determined by subtracting the cooling load 5C from the total heating load 5a+5b.

[Problem to be solved by the invention]

Since the conventional multi-room air conditioning system is configured as described above, information from the indoor unit is required to control the outdoor unit, that is, to control the compressor 2 and the outdoor heat exchanger 3. However, there was a problem in that the transmission of information between the indoor and outdoor sides became complicated and the reliability of the equipment decreased.

This invention was made to solve the above-mentioned problems. Signals for controlling the compressor and outdoor heat exchanger in the outdoor unit are taken from the outdoor unit 7), and the operation between indoor and outdoor is The purpose of the present invention is to provide a multi-room air conditioner with both cooling and heating, which improves device reliability by reducing information signals.

[Means to solve the problem]

The cooling/heating mixed multi-room air conditioner according to the present invention has a variable capacity compressor, a high/low pressure heat exchange accumulator, and an outdoor heat exchanger on the outdoor unit side, and a plurality of indoor heat exchangers on the indoor unit side. In a multi-room air conditioner with a combination of cooling and heating connected by three connecting pipes, the compressor of the outdoor unit is equipped with a high-pressure discharge pressure detector and a low-pressure suction pressure detector, and a preset target The present invention is characterized in that the capacity of the compressor, the operation mode of the outdoor heat exchanger, the speed of the blower, and the heat transfer area are controlled according to the deviation between the high pressure and the target low pressure.

[For production]

In this invention, this can be achieved by controlling the capacity of the compressor and the heat exchange capacity of the outdoor heat exchanger in accordance with the deviation between the target high pressure and the high pressure and the deviation between the target low pressure and the low pressure.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a refrigerant circuit diagram of a cooling/heating mixed type multi-room air conditioner according to the present invention, in which 101 shows an outdoor unit and 102 shows an indoor unit consisting of a plurality of heat exchangers. The outdoor unit 101 is composed of a compressor 103, a high/low pressure heat exchange accumulator 104, an outdoor heat exchanger 105, a fan 106, a compressor capacity control means 107, and an outdoor unit controller 108. A high pressure gas pipe 109 is connected to the outlet, a low pressure gas pipe 111 is connected to the inlet via the high and low pressure heat exchange accumulator 104, and a high pressure liquid pipe 110 at the bottom of the high and low pressure heat exchange accumulator 104 is connected to the indoor unit 102, respectively. In addition, a discharge pressure detector 119, a compression 4t11103 and an accumulator 10 are installed in the middle of the high pressure gas pipe 109 of the outdoor unit 101.
A suction pressure detector 12 is installed in the middle of the low pressure gas pipe 111 between 4 and 4.
0 is set. Note that one side of the outdoor heat exchanger 105 is provided with electromagnetic switching valves 116z and 117z, respectively, to enable flow path selection between the high-pressure gas pipe 109 and the low-pressure gas pipe 111, and the other side is provided with an electronic expansion valve 118z. and is connected to a high pressure liquid pipe 110.

In addition, each heat exchanger 112 to 1 of the indoor unit 7) 102
15 has one end connected to the high pressure gas pipe 109 and the low pressure gas pipe 1.
Each electromagnetic on-off valve 1 allows flow path selection with 11.
16a, 117a116b, 117b, 116c, 11
7c, 116d, and 117d, and the other is connected to high pressure liquid pipe 110 via electronic expansion valves 118a to 118d.

Next, the operation will be explained with reference to FIG. In the indoor unit 102, when only the heat exchanger 112 is operated in the heating mode and three heat exchangers 113 to 115 are operated simultaneously in the cooling mode, the flow of the refrigerant becomes a solid line arrow. In the refrigeration cycle, there is a ratio of three evaporators to one condenser, and the high pressure Pd and low pressure Ps will deviate from the target values, the high pressure Pd will be higher than the target high pressure Pd', and the low pressure Ps will be It becomes higher than the target low pressure Psθ.

By the way, if the change in high pressure is ΔPd and the change in low pressure is ΔPs for the capacity change ΔθCOmp of the compressor, then ΔPd=a ・ΔθcolIlp1 ΔPs=−bΔ
θC0Iip %a>Q, b>0, and the change in the product AK between the heat transfer area A and heat transfer rate of the outdoor heat exchanger ΔAK, the change in high pressure ΔPd=-c・ΔAK c, the change in low pressure ΔPs=-d·ΔAKc (C indicates the case where it is used as a condenser), and according to the superposition operation, it is expressed by the following formula.

ΔPd=a−Δθcomp−cΔAKcΔPs=−bΔ
θcomp-dΔAKcΔPd a
-c Therefore ()=()("00") ΔPs -b -d Δ A
If we take the Kc inverse matrix, we get the following. ...(
1) According to the above equation (1), the deviation between the target high pressure Pd'' and the value Pd of the discharge pressure detector 119 is set as ΔPd, and the deviation between the target low pressure Pd' and the value Ps of the suction pressure detector 120 is set as ΔPs. , if the controller 108 calculates the compression [11
03 capacity change amount ΔθC0Ilp and outdoor heat exchanger 105
The amount of change ΔAKc in the heat exchange capacity will appear.

〔Effect of the invention〕

As explained above, according to the present invention, the outdoor unit is equipped with a high pressure discharge pressure detector, a low pressure suction pressure detector, and a controller, and the outdoor unit is equipped with a high pressure discharge pressure detector, a low pressure suction pressure detector, and a controller, and the Since the capacity of the compressor and the heat exchange capacity of the outdoor heat exchanger are controlled, information from the indoor unit is required, and signal transmission between the indoor and outdoor units can be reduced as much as possible. A highly reliable device can be obtained.

[Brief explanation of drawings]

Fig. 1 is a refrigerant circuit diagram of a multi-room air conditioner with mixed heating and cooling according to an embodiment of the present invention, Fig. 2 is a flow chart of the refrigerant of the apparatus shown in Fig. 1, and Fig. 3 is a refrigerant circuit diagram of a conventional multi-room air conditioner. It is a circuit diagram. 101... Outdoor unit, 1o2... Indoor unit, 103... Compressor, 104... High and low pressure heat exchange accumulator, 105... Outdoor heat exchanger, 107...
- Compressor capacity control means, 10B... outdoor unit controller, 109... high pressure gas pipe, 110... high pressure liquid pipe,
111...Low pressure gas pipe, 112-115...Indoor heat exchanger, 116a=116d, 117a-117d・
...Solenoid on/off valve, 118a-118d...Electronic expansion valve, 116z, 117z...Solenoid switching valve, 118z...
・Electronic expansion valve, 119...Discharge pressure detector, 120・
...Suction pressure detector. Note that the same reference numerals in the figures indicate the same or equivalent parts. Figure 1

Claims (1)

[Claims] A mixed cooling/heating type that has a variable capacity compressor, high/low pressure heat exchange accumulator, and outdoor heat exchanger on the outdoor unit side, and connects the multiple indoor heat exchangers on the indoor unit side with three connecting pipes. In the multi-room air conditioner, the compressor of the outdoor unit is equipped with a high-pressure discharge pressure detector and a low-pressure suction pressure detector, and the above-mentioned A mixed cooling and heating multi-room air conditioner, characterized in that the capacity of a compressor, the operation mode of the outdoor heat exchanger, the speed and heat transfer area of a blower are controlled.