JPS6011789B2 - Multi-room air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit, and an object of the present invention is to provide a device that is inexpensive and has excellent controllability. purpose.

First, a conventional multi-room air conditioner will be explained.

In conventional multi-room air conditioners, the liquid side pipes and gas side pipes in the outdoor unit are branched for the number of indoor units, and a solenoid valve is attached to each of the liquid side branch pipes and gas side branch pipes created by this branching. was installed to control the refrigerant sent to each indoor unit by turning on and off these solenoid valves.

For this reason, it has not been possible to continuously control the amount of cold soot required for each indoor unit in response to momentary load fluctuations. In other words, the solenoid valve for each indoor unit is frequently opened and closed by the temperature controller for each indoor unit, so when the solenoid valve is closed by the temperature controller and the refrigerant flow stops, the room temperature rises and becomes uncomfortable. It was in a state.

Furthermore, since the refrigerant continuously flows when the solenoid valve opens and closes, there is a problem in that refrigerant noise and solenoid valve opening and closing noise are likely to be generated. In addition, at least each indoor unit requires a cooling-dedicated throttle device, the outdoor unit requires a heating throttle mechanism, and a check valve to bypass these throttle mechanisms, and the refrigerant that accumulates in the idle room during heating operation is required. A bypass circuit is required to remove the refrigeration circuit and form a proper refrigeration cycle, which makes the refrigeration cycle complicated, making it difficult to manufacture, and requiring the use of many expensive parts, resulting in high costs. Next, a conventional example and an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a conventional multi-room air conditioner, in which an outdoor unit 1 includes a compressor 2, a discharge muffler 3, a four-way valve 4, a heat source side heat exchanger 5, a liquid side main pipe 6, and liquid side branch pipes 7a, 7b. , 7c, the gas side branch pipes 8a, 8b, 8c, the gas side main pipe 9, the accumulator 10, the heating throttle mechanism 11 provided in the liquid side main pipe 6, and the flow of refrigerant in parallel with the heating throttle mechanism 11 during heating. Check valve 12 provided so that the side is on the blocking side, heating throttle mechanism 11 of liquid side main pipe 6, liquid side branch pipes 7a, 7b,
7c, and a bidirectional solenoid valve 1 provided in each liquid side branch pipe 7a, 7b, 7c.
5a? 15b, 15c, each liquid side branch pipe 7a, 7b, 7c
A check valve 17a connects the connection ports 16a, 16b, 16c between each solenoid valve 15a, 15bg 15c and each indoor unit 38a, 30b, 30c (only 30c is not shown) and the low pressure circuit 20 during heating operation. , 17b, 17c and aperture 18
Bypass pipe 19a, military 9b, turtle gc and gas side branch pipe 8a via series connection of a, 18b, 18c, respectively
, 8b, 8c, respectively, have two-way solenoid valves 21a.
, 21b9 2 turtles c, indoor unit 3Qa, 3
Qb is the user side heat exchanger 31a, 31b, cooling throttle mechanism 32a; 32b, cooling throttle mechanism 32a, 3, respectively.
It consists of check valves 33a and 33b which are provided in parallel with 2b so that the flow of refrigerant during cooling operation is blocked.

In the above configuration, "during cooling operation, cold soot is pushed out from the compressor 2 and discharged from the discharge muffler 3", the four-way valve turtle, the heat source side heat exchanger 5,
The branch point 13 is reached via the check valve blade 2. Indoor unit 3Qa here? Assuming that three rooms 30b and 30c are in operation, each indoor unit 30a? 30b,3
Solenoid valves 15a, 15b, 15c in liquid side branch pipes 7a, 7b, 7c connected to 0c and gas side branch pipes 8a, 8b, 8
The solenoid valves 21a, 21b, and 2c in c are opened, and the cold soot passing through the indoor unit 30a passes through the solenoid valve 15a, the throttle mechanism 32a, the user-side heat exchanger 31a, and the solenoid valve 21a.
In addition, the solvent passing through the indoor unit 30b is controlled by a solenoid valve 15b,
Cold soot passing through the throttle mechanism 32b, utilization heat exchanger 31b, solenoid valve 21b, and indoor unit 31c is removed by the solenoid valve 15.
c, throttle mechanism 32c, user side heat exchanger 31c, solenoid valve 2
1c, and return to the compressor 2 via the four-way valve 4 and the accumulator 10. At this time, each indoor unit 30a,
The amount of cold soot flowing through 30b and 30c is the same for each indoor unit 30a.
, 30b, 30c aperture mechanisms 32a, 32b, 32c
It is determined by the total resistance of each chamber system including the resistance of
It is not determined by the cooling load of the rooms A, B, and C to which the indoor units 30a, 30b, and 30c are installed. In actual refrigerant flow control, when the temperature in each room drops to the set value, the solenoid valves 5a-21a, 15b-2 for each room are
1b, 15c-21c are closed and each indoor unit 30a, 3
When the soot supply to 0b and 30c is stopped and the room temperature rises, the solenoid valves 15a-21a, 15b-21b, 15c-
21c opens and cold water is supplied to each indoor unit 30a, 3Qb, 30c intermittently.

Therefore, the temperature of the air blown from each indoor unit 30a, 30b, 30c is
"By closing the stove 5c-21c, the air rises significantly, creating an uncomfortable situation, and at the same time, by opening and closing the solenoid valve, rooms A, B, and C
The room temperature of the room constantly fluctuates within a certain range. On the other hand, during the heating operation, the air flow passes through the compressor 2, the discharge muffler 3, and the four-way valve, and reaches the gas side branch pipes 8a, 8b, and the crab c.

Assuming that three indoor units 30a, 30b, and 30c are in operation, each indoor unit 30a, 30b
, 38c, and the solenoid valves 21a, 28b, 2c in the gas side branch pipe 8b, 8c connected to the liquid side branch pipe 7a? 7
Solenoid valve 15a in b, 7c? 15b and 15c are opened and the soot passing through the indoor unit 38a is removed from the solenoid valve 21a.
Utilization side heat exchanger 31a, check valve 33a, solenoid valve amount 5a
In addition, the cold soot passing through the indoor unit 38b is passed through the solenoid valve 21b, the user-side heat exchanger 31b, the check valve 33b, and the solenoid valve 15b, and the cold soot passing through the indoor unit 30c is passed through the solenoid valve 21c, the user-side heat exchanger 31b, and the check valve 33b. Through the exchanger 31c, the check valve 33c, and the solenoid valve 15c, the liquid receiver Turtle, the heating throttle mechanism 11,
The heat source side heat exchanger 5, the four-way valve 4 return to the compressor 2 via the accumulator 10. At this time, each indoor unit 30a
, 30b, 30c is determined by the total resistance of the pipes in each room system including each indoor unit, as in the case of cooling.
It is not determined by the heating load of rooms A, B, and C to which the indoor units 30a, 30b, and 30c are attached.

In actual refrigerant flow control, when the temperature of each room rises to the set value, the solenoid valves 21a-15a, 21b-15b, 2
1c-15c are closed and each indoor unit 30a, 30b, 3
When the refrigerant supply to 0c is stopped and the room temperature falls, the solenoid valves 21a-15a, 21b-15b, and 21c-15c are opened, and refrigerant is intermittently supplied to each indoor unit 30a, 30b, and 30c. It will be done. Therefore, each indoor unit 30a, 30b. The blowing air temperature of 30c is determined by the solenoid valves 21a-15a, 210-15b and 21c-
When the valve 15c is closed, the room temperature drops significantly, creating an uncomfortable condition, and at the same time, the room temperature in rooms A, B, and C constantly fluctuates within a certain range due to the opening and closing of the crab valve. Here, when the indoor unit 30c is stopped again, the solenoid valve 21c. 15c is closed.

Therefore, the cold butterflies that had been circulating in the indoor unit 30c until just before the operation stopped accumulates in the indoor unit 30c due to the closure of the solenoid valves 21c and 15c, and the cold butterflies that were circulating in the indoor unit 30c accumulate in the indoor units 30a and 30b.
Since the amount of refrigerant to be circulated decreases and a proper refrigeration cycle cannot be formed, the bypass pipe 19c, in which the check valve 17c and the throttle 18c are connected in series, is connected to the solenoid valve 15c and the connection port 16.
It is connected to the low-pressure pipe line 20 during heating operation from between c to drain cold soot inside the indoor unit 30c. As mentioned above, conventional multi-chamber air conditioners require many electromagnetic valves, throttling mechanisms, check valves, and drain bypass circuits, making the refrigeration cycle extremely complex and costly. At the same time, it had the major drawback of being difficult to manufacture and prone to failure.

Next, before describing one embodiment of the present invention, an example of a forward and reverse flow type thermal haze type expansion valve used in the present invention will be described with reference to FIG.

In the figure, a thermoelectric expansion valve 40' consists of a valve part 1 and a valve driving part 42.

The valve portion consists of a valve frame 43 and a valve body 44. The valve frame 43 is provided with a valve seat portion 45 and has an inflow boat 46 and an outflow boat 47 through which fluid flows in and out, and refrigerant pipes 48 and 49 are connected to each boat 46 and 47, respectively. The valve body 44 consists of two upper and lower members 50, 51 connected together, and in these members 50, 51, passages 52, 53 are formed for transporting the outflow boat 47 side and the inside of the valve driving portion 42. .
A check valve 54 is provided between the passages 52 and 53 to prevent soot from flowing from the passage 53 to the passage 52. The valve body 44 is provided in a hole 55 formed in the valve frame 43 so as to be vertically slidable. On the other hand, the valve driving portion 42 forms a sealed space 58 with an upper casing 56, a lower casing 57, and the valve frame 43. this space 58
Two bimetals 59 and 60 are stored inside.
Bimetal 59 on both sides, Subesa 61 at both ends of the river.
They are arranged in parallel via 62. And both bimetal 5
Holes 63 and 64 are bored in the center of the valve bodies 9 and 60, and a support pin 65 fixed to the center of the inner surface of the upper casing 56 is inserted from above into the hole 63 of the upper bimetal 59. By inserting the formed pin portion 66 into the hole 64 of the lower bimetal 60 from below, both bimetals 59
, 60' are supported within the space 58. Note that the valve body 44 is
It is always urged upward by a spring 68 via the seat 67. An electric heater 69 forcibly heats the upper bimetal 59 and is wound around the upper bimetal 69.

Terminals 70 and 71 are connected to both ends of the electric heater 69 and are provided through the upper casing 56.

This upper bimetal 59 is forcibly heated by an electric heater 69, so that both ends thereof are directed upward (in the direction of arrow A in the figure).
It transforms so that it moves. Therefore, when the electric heater 69 is energized, the upper bimetal 59 deforms and the spring 68 pushes the valve body 44 upward, causing the valve seat 45 to
and the lower end of the valve body 44 is opened. That is, the valve is opened. The degree of opening of the valve in this case is adjusted by the amount of power supplied to the electric heater 69. That is, if a large force pressure is applied, the upper bimetal 59 will be greatly deformed and bent, and the valve resistance will increase.On the contrary, the voltage to the electric heater 69 will be 4.
In this case, the amount of deformation of the upper bimetal 59 is small, and the degree of deformation of the valve is small. The lower bimetal 60 is a bimetal for compensating the load condition, and is deformed by the temperature influence of the rich medium flowing into the space 58 from the sliding surface between the hole 55 and the valve body 44 and the temperature of the surrounding air. . The thermal tortoise-shaped expansion valve 40 is a normally-closed, forward-reverse flow type expansion valve, and the cooling fluid flows in from the inflow boat 46 and is formed between the valve body 44 and the valve seat 45. It goes without saying that the flow flows out of the outflow boat 47 through the constriction, and vice versa, the flow flows from the outflow boat 47 and flows through the constriction formed between the valve body 44 and the valve seat 45. It is also possible for the flow to flow out from the port 46. In this case, due to the shape of the valve, it is better to flow from the inflow boat 46 to the outflow boat 47.
Compared to the case where the refrigerant flows in the opposite direction, if the degree of restriction is the same, the flow resistance of the refrigerant becomes slightly smaller. In addition, the inflow boat 46
When the pressure on the side becomes high and the pressure on the outflow boat 47 side becomes low, a part of the cold soot flows into the space 58 from the sliding surface between the valve body 44 and the hole 55, but this refrigerant flows into the passage. 5
2, 53 and the check valve 54 to the outflow boat 47 and does not accumulate in the space 58. On the other hand, spilled boat 4
When the pressure on the 7 side becomes higher than that on the inflow boat 46 side, the check valve 54 closes and almost no refrigerant flows into the space 58. Next, an embodiment of the multi-chamber air conditioner according to the present invention will be described with reference to FIG.

In the same figure, the outdoor unit 81 has a compressor 82, a discharge muffler 83, a four-way valve 84, a heat source side heat exchanger 85, a liquid side main pipe 86, a liquid receiver 87 to a liquid side main pipe 86 branched as many as the number of indoor units. Liquid side branch pipes 88a, 88b, 88 made by
c, thermoelectric expansion valves 40a, 40b, 40c and liquid receivers 90a, 90b, 90 provided in this liquid side branch pipe, respectively;
c, bidirectional solenoid valves 91a, 91b, 91c, respectively;
Gas side branch pipes 92a, 92b, 92c are interposed and branched in the number of indoor units 95a, 95b, 95c, a side main pipe 93 formed by merging these gas side branch pipes 92a, 92b, 92c, and an accumulator 94. It consists of etc.

In addition, each liquid side branch pipe 88a, 88b, 8 of the outdoor unit 81
8c, and the indoor units 95a, 95b, 95c connected to the gas side branch pipes 92a, 92b, 92c, respectively, are composed of usage side heat exchangers 96a, 960, 96c, etc., respectively. Now, the operation during cooling operation in this configuration will be explained.

First, it is assumed that one indoor unit 95a is being operated.

The refrigerant gas discharged from the compressor 82 is passed through the discharge muffler 83
, passes through the four-way valve 84, is liquefied in the heat source side heat exchanger 85, and is sent to the liquid receiver 87 via the liquid side main pipe 86. The liquid refrigerant exits the liquid receiver 87, passes through the thermoelectric expansion valve 40a in the liquid side branch pipe 88a, becomes a low-pressure liquid, passes through the liquid receiver 90, goes to the user-side heat exchanger 96a of the indoor unit 95a, and evaporates into a gaseous state. Bidirectional solenoid valve 9 that is energized and open
1a, the gas side branch pipe 92a, the four-way valve 84, and the accumulator 94 before returning to the compressor 82. At this time, indoor unit 95
b, 95c are stopped, so the thermoelectric expansion valves 40b, 4
No voltage is applied to 0c. Therefore, the valve part is closed and the liner medium is not allowed to flow. Also, a bidirectional solenoid valve 91
If b and 91c are left open, the thermal fin type expansion valves 40b and 40
The cold soot that leaks from the indoor units 95b and 95c and tends to accumulate in the indoor units 95b and 95c when they are inactive can be extracted to the low-pressure gas side main pipe during cooling operation, and a normal refrigeration cycle can be formed. When the indoor unit 95a is operated in this manner, if a control device is provided that can change the voltage applied to the thermoelectric expansion valve 40a depending on the load condition of the indoor unit 95a, etc., the flow rate of the cold soot to be supplied can be freely adjusted. It can be changed.

Therefore, extremely comfortable air conditioning can be achieved simply by continuously changing the opening degree of the thermoelectric expansion valve 40a while the compressor 82 continues to operate. Next, when the indoor units 95b to 95c are additionally operated while the room in which the indoor unit 95a is installed is sufficiently cooled, the thermoelectric expansion valves 40b and 40c and the bidirectional solenoid valves 91b and 9
1c is energized, and cold soot flows through the indoor units 95b and 95c.

Now, each indoor unit 95a, 95b, 95c is
, 95b, 95c thermoelectric expansion valves 40a, 40b, 4
Assuming that the voltage is controlled to open the opening of 8c, and the air conditioning load in the room where the indoor units 95b and 95c are installed is much larger than the air conditioning load in the room where the indoor unit 95a is installed, A large voltage is applied to the thermoelectric expansion valves 40b and 40c, and the valves are opened to the maximum extent, while a very large voltage is not applied to the thermoelectric expansion valve 40a, so that the valve opening is small.

Therefore, many butterflies flow through the indoor units 95b and 95c, and air conditioning is performed in accordance with the load of the room. Next, the operation during heating operation will be explained.

First, it is assumed that 9531 indoor units are in operation.
The refrigerant gas discharged from the compressor 82 is passed through the discharge muffler 83
, the four-way valve 84, the gas side branch pipe 92a, and the indoor unit 95a through the bidirectional solenoid valve 91a where voltage is applied and the valve is opened.
It is liquefied in the utilization side heat exchanger 96a. Subsequently, this liquefied cold soot passes through the liquid receiver 90 and the thermal tortoise-shaped expansion valve 40a to which a voltage is applied, becoming a low-pressure liquid, and further passes through the liquid side branch pipe 88a, the liquid receiver 87, and the liquid side main pipe 86. It is evaporated in the heat source side heat exchanger 85 and returns to the compressor 81 through the four-way valve 84 and the accumulator 94. Now here and now thermoelectric expansion valve 40a
, 40b, and 40c are of the type that allow the flow of cold soot in the opposite direction to the flow of cold soot during cooling, and perform the function of an expansion valve in the same way as when cooling soot. Therefore, one thermoelectric expansion valve can perform the throttling action during cooling. Since it can also be used for heating, it is cheaper than a type that uses dedicated expansion valves for both cooling and heating, and requires less space to store the expansion valves.

Also, the solenoid valves 91b, 91 in the gas side branch pipes 92b, 92c connected to the indoor units 95b, 95c that are inactive.
By closing c and applying voltage to the thermoelectric expansion valve in the liquid side branch pipe and opening the valve part, the user side heat exchangers 96b and 96c in the indoor units 95b and 95c will be operated at low pressure during heating operation. Become. Therefore, the user side heat exchangers 96b, 9
The refrigerant in 6c does not accumulate. Therefore, unlike the conventional multi-room air conditioner, there is no need for a bypass circuit for removing the media from the idle indoor unit during heating operation, resulting in lower costs and space savings.

In addition, the operation of the thermoelectric expansion valve when heating one room and when operating two or more rooms can be considered in the same way as when cooling.
It becomes possible to send the required amount of cold soot to each indoor unit by controlling the degree of valve function commensurate with the air conditioning load of the room in which each indoor unit 95a, 95b, 95c is installed. In addition, in this embodiment, an example was explained in which a normally closed type thermoelectric expansion valve is used, in which the valve body closes when the power supply to the electric heater is cut off.However, conversely, when the power supply to the electric heater is cut off, the valve body closes. The same control can be achieved by using a thermoelectric expansion valve of the normal type, whose body opens and whose valve body can be controlled depending on the degree of energization to the electric heater.

In this case, compared to the normally open type, the refrigerant flows at the same time as the compressor is operating, so the start-up characteristics are better. Since pressure can be maintained between the low pressure side and the low pressure side, there is no need to wait until the pressure is balanced before restarting the compressor, as was the case in the past. As described above, the air conditioner according to the present invention uses one thermoelectric expansion valve for each indoor unit to perform a throttling action during cooling and heating, so it is inexpensive and reduces the air conditioning load in each room. It is possible to control the amount of refrigerant accordingly and achieve extremely comfortable temperature control, and at the same time, it eliminates the need for a bypass pipe to drain liquid from the idle unit during heating, making the refrigeration cycle extremely simple.
It has the great effects of being inexpensive, making the device more compact, making it easier to manufacture, and reducing failures.

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of a conventional multi-chamber air conditioner, Fig. 2 is a sectional view of a thermoelectric expansion valve in an embodiment of the present invention, and Fig. 3 is a multi-chamber diagram in an embodiment of the present invention. It is a refrigeration cycle diagram of a type air conditioner. 2,82... Compressor, 4,84... Four-way valve, 5,85.
...Heat source side heat exchanger, 31a, 31b, 96a,
96b, 96c... User side heat exchanger, 40, 4
0a, 40b, 40c...Thermoelectric expansion valve, 88a,
88b, 88c...Liquid side branch pipe, 92a, 92b, 9
2c...Gas side branch pipe, 91a, 91b, 91c...
··solenoid valve. 1 screen with 1 screen, 3 screens with 2 screens

Claims (1)

[Claims] 1. A plurality of indoor units each consisting of a user side heat exchanger, etc. are connected to one outdoor unit consisting of a compressor, a four-way valve, a heat source side heat exchanger, etc. via connection piping, and the liquid in the outdoor unit is A forward and reverse flow type thermoelectric expansion valve is provided in each of the plurality of liquid side branch pipes branched from the side main pipe, and a solenoid valve is provided in each of the plurality of gas side branch pipes branched from the gas side main pipe, and the thermoelectric expansion valve is opened. A multi-room air conditioner configured to change the temperature according to the air conditioning load of the indoor unit.