JPS6040786B2 - 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 its purpose is to enable quiet heating operation. It is to be one.

In a conventional multi-room air conditioner, when the indoor unit is in heating operation with the compressor running,
When adding another indoor unit to perform heating operation, the gas-side solenoid valve and liquid-side solenoid valve that control the flow of refrigerant to the indoor heat exchanger of the indoor unit subjected to additional heating operation were opened at the same time. . However, before heating operation was started, the indoor heat exchanger of the indoor unit that was operated with this powerful misaki heating operation had stopped the flow of refrigerant by closing the gas side solenoid valve and the liquid side solenoid valve, and the flow of refrigerant was stopped due to low pressure. Since the pressure was almost the same as the suction pressure of the compressor, opening the gas-side solenoid valve and the liquid-side solenoid valve at the same time caused high pressure to flow into the low-pressure chamber and heat exchanger. Gas flows in at a high speed, and the flowing refrigerant generates a loud impact sound, and the sudden movement of the pilot valve part of the gas-side solenoid valve causes a clicking sound. These impact noises and lunch box noises are diffused by the indoor unit, and there is a serious problem in that large noises and vibrations are also generated from the floor and walls around which the indoor unit is attached. Further, these drawbacks similarly occur even when only the liquid side solenoid valve is opened in the same state. The present invention is intended to eliminate the above-mentioned drawbacks, and will be explained below with reference to the drawings.

FIG. 1 is a refrigeration cycle diagram of an embodiment of the multi-chamber air conditioner according to the present invention, in which the outdoor unit 1 includes a compressor 2, a discharge muffler 3, a four-way valve 4, a heat source side heat exchanger 5, and a liquid side main pipe. 6,
Liquid side branch pipe 7a formed by branching the liquid side main pipe 6 at the branch point 13
, 7b, 7c, the same number of gas side branch pipes 8a, 8b, 8c as the liquid side branch pipes 7a, 7b, 7c, these gas side branch pipes 8a.
, 8b, 8c are assembled into a gas side main pipe 9, an accumulator wealth 8, and a noren curtain mechanism 11 provided in the liquid side main pipe 6.
A check valve 12 is provided in parallel with the heating throttle mechanism 11 to prevent the flow of refrigerant during heating operation, and the heating diaphragm blade 1 of the liquid side main pipe 6 and the liquid side branch pipe 7a? 7b,? c.
The liquid receiver provided between the branch part 13 and each liquid side branch pipe? a
,7b? Bidirectional crest mechanism during yc 22 huan 9 22
b9 Solenoid valve 21a with bidirectional flow installed in series with 22c Fumo a, vine 5b, 15c "Mother of solenoid valve 21a with bidirectional flow installed in each gas side branch pipe 2nd group b, 21c, during heating operation The check valve 17a with the low pressure circuit 28 side as the flow blocking side; the solenoid valves 5a, 5b, and 15c are made by connecting in series the tortoise 7b?c, the squeeze tortoise 8a, the sergeant crab b, and the wealth 8c, respectively. Indoor unit 39a? 38b, 38c connection port weight 6a
, 1 deprivation b hen Liquid side branch pipes 7a, 7b, between turtle 6c, ? Bypass pipe gas connecting c and low pressure circuit 2 during heating operation
Tsubasa gb? 19c, the check valves 23a, 23b, 23c with the gas side branch pipes 8a, 8b, 8c side as the flow blocking side are connected in series with the solenoid valves 24a, 24b, 24c, respectively, and the "solenoid valves" are connected in series from the liquid side main pipe 6. 21a, 21b, 21c and
Connection port 25a with each room unit 30a, 30b, 30c
? It connects the gas side branch pipes 8a, 8b and 8c between 25b and 25c, and consists of a bypass pipe 26a and 26b, 26c.

In addition, the indoor units 30a, 30b, and 30c each include a user-side heat exchanger 31a, three stoves b, and 31c.
In addition, the indoor units 30a, 30b, and 30c are connected to the outdoor unit i through liquid side pipes 32a, 32b, and 32c, and gas side pipes 33a, 33b, and 33c, respectively. Second
The figure shows an embodiment of the electric circuit of a multi-room air conditioner according to the present invention, in which the coil 15a' of the solenoid valve 15a, the coil 21a' of the solenoid valve 21a, and the solenoid switch coil 2a are the operation switch of the indoor unit 30a, respectively. 40a relay contact 4
The power supplies 5 are connected in parallel through a circuit in which the power supplies 5a are connected in series, and similarly the coil 15b' of the solenoid valve 15b and the solenoid valve 21 are connected in parallel.
The coil 21b' and the electromagnetic switching coil 2b of the solenoid valve 15c are connected in parallel to the power supply 50 through a circuit in which the operation switch 40b and the relay contact 45b of the indoor unit 30b are connected in series, and the coil 15c' of the solenoid valve 15c and the electromagnetic switching coil 2b are connected in parallel. The coil 21c' of the electromagnetic valve 21c and the electromagnetic switch coil 2c are connected in parallel to the power supply 581 through a circuit in which the operating switch 48c and the relay 6c of the indoor unit 30c are connected in series.

In addition, the motor 2' of the compressor 2 has electromagnetic switch coils 2a and 2.
The normally open contacts 2 of the solenoid valves 2b and 2c are connected in series with the circuit in which the contacts 2b' and 2c' are connected in parallel and connected to the power supply 50. Furthermore, the relay contact 46a and the coil contact 2 of the solenoid valve 2a are connected in series. Connected line and relay contact 4 Solenoid valve 2
The line in which the coil 24 of the coil 4b is connected in series, the line in which the relay contact 46c and the coil 24c' of the solenoid valve 24c are connected in series, and the operation switch 48a, 4Qb, which consists of the coil 4' of the four-way valve, a microcomputer, etc. By detecting the ON and OFF states of eel c, the control device 44' controls the relay contact umbrella Sa, turtle 5b, 45C-46a, 46b? 46c. The power supplies 601 are connected in parallel to each other.Here, the operation of the multi-room air conditioner according to the present invention in the above configuration during heating operation will be explained.

Now, with the cooling/heating changeover switch 42 turned on to the heating side contact 48 side, the operation switch of the indoor unit 30a is turned on.
If a is turned on, the control device 44 consisting of a microcomputer or the like detects that the indoor unit 30a has issued the first signal to rotate the motor 2' of the compressor 2, which had been stopped, and turns on the normal operation of the relay 45a. Coil 15a of solenoid valve j5a, 21a to keep the closing contact closed
``Thing 2'' Apply fin pressure to Tomi a' and the electromagnetic switch coil 2a, open the passages of the electromagnetic valves 15a and 21a, close the normally open contact 2a' of the electromagnetic switch coil 2a, and close the motor 2 of the compressor 2.
Rotate ′.

At this time, as mentioned earlier, the control device 44
Since it is detected that the motor 0a has issued the first control signal to rotate the motor 2' of the compressor 2 which had been stopped, the coil 24a' of the bypass solenoid valve 24a is activated to keep the relay contact 46a open. No power is supplied. In this way, since the refrigerant gas is passed through the coil 4' of the four-way valve 4, the refrigerant gas discharged from the compressor 2 passes through the four-way valve 4 and into the gas side main pipe 9.
The liquid side branch pipe 8a passes through the solenoid valve 21a, the connection port 25a, and the gas side pipe 33a, reaches the indoor heat exchanger 31a of the indoor unit 30a, and is liquefied, and then the liquid side main pipe 32a, the connection port 16a, the solenoid valve 15a, and the liquid Side branch pipe 7a, throttle device 7a,
The heating throttle mechanism 11 passes through the branch point 13 and the liquid receiver 14.
It passes through the low-pressure circuit 20 during heating operation, evaporates in the heat source side heat exchanger 5, passes through the four-way valve 4 again, returns to the compressor 2 via the accumulator, and forms a refrigeration cycle, and the indoor unit 30a is operated during heating operation. Drive. Also, during heating operation of this indoor unit 30a, other indoor units 30b, 3
Since the contacts of the operation switches 40b and 40c are open at 0c, heating operation is not performed, and the solenoid valves 5b, 21b,
15c, 21c coils 15b', 21b', 15c'
, 21c' are not energized, so the solenoid valves 15b, 2
1b, 15c, and 21c close the passages. Therefore, the refrigeration circuit 32b including the indoor heat exchanger 31b, which is closed by the solenoid valve 21b and the solenoid valve 15b, and the solenoid valve 2
1c and the solenoid valve 15c, and the refrigeration circuit including the indoor heat exchanger 31c is in a state where cold soot does not flow.

However, in reality, the solenoid valves 21a, 21b, 21c, 15a
, 15b, 15c, etc. cannot completely stop the flow of medium and there is some leakage, so indoor units 30b, 3 that are stopped
The liner medium gradually accumulates in the indoor heat exchangers 31b and 31c at 0c.

However, when a large amount of refrigerant accumulates in the indoor heat exchangers 3ib and 31c, the amount of cold soot flowing through the indoor heat exchanger 31a of the indoor unit 30a during operation decreases, resulting in a decrease in heating capacity and There is a problem that phosphorus loss (2) is caused. Therefore, by-pass pipes 19b and 19c, one end of which is connected to the low-pressure circuit 20 during heating operation, are used to extract the medium accumulated in the indoor heat exchangers 31c and 31b. Therefore, the indoor unit 30b is stopped.
, 30c, the refrigerant pressure in the indoor heat exchangers 31b, 31c is in the same low pressure state as in the low pressure circuit 20 during heating operation. Under such circumstances, when additionally operating another indoor unit 30b, the subordinate control method
The indoor heat exchanger 31 was at low pressure because it was open at the same time.
Due to the pressure difference, high-pressure soot gas flows into the tank b at high speed, causing loud refrigerant impact sounds, vibrations, and strong solenoid valve 21b hitting noises.

Therefore, in the case of the present invention, as shown in the valve operation timing chart of FIG.
When b is turned on, the control device 44 consisting of a microcomputer etc. switches the operation switch 40b to the motor 2 of the compressor 2 since the operation switch 40a has already been turned on.
' is detected to have been turned on during operation, and the relay point 45 is turned on.
b is opened, relay contact 46b is closed, and voltage is applied to coil 54b' of bypass solenoid valve 24b. The refrigeration circuit 6, in which medium-pressure liquid is flowing, and the refrigeration circuit 32b, which has been stopped and has been at low pressure until now, are connected. is passed through the bypass pipe 26b, and as the liquid soot enters, the pressure of the refrigeration circuit 32b gradually increases, and liquid soot accumulates in the gas side pipe 33b.

Since the soot flowing into the refrigeration circuit 32b through the bypass pipe 26b is in liquid form, the inflow speed is slow and no impact noise or the like is generated. When the pressure inside the refrigeration circuit 32b rises to some extent and the solenoid valve 21b is opened, the indoor heat exchanger 3
1b, the control device 44 opens the relay contact 46b and closes the relay contact 45b, which causes the solenoid valve in the refrigeration circuit 32b to supply cooling air to the indoor unit 30b. 2 stoves b, 15b
The coils 21b', 15b' are energized, and the solenoid valves 21b,
The passage 15b is opened. At this time, the refrigerant flowing through the solenoid valve 21b enters the refrigeration circuit 32b with a small pressure difference, and since the amount of refrigerant in the gas side pipe 33b is large, much of the energy due to the pressure difference is changed into kinetic energy. No impact noise or vibration occurs. Also, the solenoid valve 21b does not undergo sudden valve punching, so the valve will not be damaged. Further, when the bypass solenoid valves 24a, 24b, 24c are opened, the electric circuit may be configured to open the solenoid valves 15a, 15b, 15c in order to promote pressure rise in the refrigeration circuits 32a, 32b, 32c which have been stopped until now. . Furthermore, in the electric circuit shown in FIG. 2, a temperature controller is provided in series with the operation switches 40a, 40b, and 40c, and while the pond indoor unit is being operated and the compressor is in operation, "When the operation switch is turned on and the temperature controller is reset," Exactly the same effect can be obtained by performing similar control on the bypass solenoid valves 24a, 24b, 24.
The opening time of c may be calculated and determined each time by a microcomputer, taking various conditions into consideration.

That is, the various conditions include various factors such as the number of units in the operating room, thermostat temperature, and thermostat OFF time. Alternatively, the bypass solenoid valve may be controlled by a pressure switch or the like. As mentioned above, in the multi-room air conditioner according to the present invention, when the compressor is also running and at least one indoor unit is in heating operation, when the other indoor units are brought into additional heating operation or restarted by thermostat, etc., the main pipe on the liquid side is After bypassing the medium pressure cold soot to the gas side branch pipe between the gas side solenoid valve and the indoor unit and increasing the pressure in the indoor heat exchanger of the indoor unit that was inactive, the gas side solenoid valve and the liquid were Since the side solenoid valve is opened, quiet heating operation is possible, with no noise or vibrations coming from the indoor unit, and the life of the gas side solenoid valve is extended without the occurrence of severe gas side solenoid valve hitting. It has great effects such as being able to

[Brief explanation of the drawing]

Fig. 1 is a refrigeration cycle diagram of an embodiment of the multi-chamber air conditioner according to the present invention, Fig. 2 is an electric circuit diagram of the multi-chamber air conditioner according to the present invention, and Fig. 3 is an operation timing chart of the solenoid valve. It is a diagram. 1...Outdoor unit, 15a, 15b, 15c
...Solenoid valve, 21a, 21b, 21c...Solenoid valve,
24a, 24b, 24c... Solenoid valve, 30a, 38
b, 30c... Indoor unit, 44... Control device, 40a, 40b, 40c, 45a, 45b, 45C
, 46a, 46b, 46C, . ．． ．． ．． ．． relay contact. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. In a multi-room air conditioner in which multiple indoor units are connected to one outdoor unit by connecting piping, the liquid side main pipe of the outdoor unit is branched into the liquid side branch pipes created by branching the liquid side main pipe to the number of indoor units. A swell device and a liquid-side solenoid valve are connected in series, and a gas-side solenoid valve is provided in each gas-side branch pipe created by branching the gas-side main pipe to the number of indoor units, and from the liquid-side main pipe, A bypass pipe is provided which communicates with the gas side branch pipe between the gas side solenoid valve and the heat exchanger of each indoor unit, a solenoid valve is provided in each of the bypass pipes, and each liquid side solenoid valve is provided with a solenoid valve. and a multi-room air conditioner, in which liquid drain pipes are connected from each of the liquid side branch pipes between the indoor heat exchangers of the indoor units and the pipes that are at low pressure during heating operation.