JPS5914699B2 - 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.
One of its purposes is to enable quiet heating operation.

In a conventional multi-room air conditioner, when the compressor is operated (・) and the indoor unit is in heating operation (・), if another indoor unit is added to perform heating operation, this The gas-side solenoid valve and the source-side solenoid valve that control the flow of refrigerant to the indoor heat exchanger of the indoor unit that was in additional heating operation were opened at the same time.

However, the indoor heat exchanger of the indoor unit subjected to this additional heating operation stopped the flow of refrigerant by closing the gas side solenoid valve and the source side solenoid valve before heating operation, and the low pressure Since the pressure was connected to the circuit that was
Ta.

Therefore, if the gas side solenoid valve and the source side solenoid valve are opened at the same time, high pressure gas will flow into the low pressure indoor heat exchanger at high speed, and this flowing refrigerant will generate loud °C and impact sounds, and the gas side By rapidly moving the pilot valve part of a solenoid valve, a clicking sound may be generated.

These impact sounds and lunchbox sounds are magnified by the indoor unit, and can be heard from the floor or wall where the indoor unit is installed.
Generating noise and vibration can cause problems.

Further, these drawbacks occur in the same manner even when the same condition is maintained and only the source side solenoid valve is opened.

The present invention is intended to eliminate the above-mentioned drawbacks, and one embodiment thereof will be explained below with reference to the drawings.

FIG. 1 is a refrigeration cycle diagram of an embodiment of a multi-room air conditioner according to the present invention, 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, and a source side main pipe. 6,
Liquid branch pipe 7a formed by branching the source 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 branch pipes 7a, 7b, 7c, and these gas-side pipes 8a.

A heating throttle mechanism 11 provided in the gas side main pipe 9, the accumulator 10, and the source side main pipe 6, which are made by collecting 8b and 8c, is parallel to the heating throttle mechanism 11 and blocks the flow of refrigerant during heating operation. The check valve 12 provided so as to be on the side, the heating throttle mechanism 11 of the source side main pipe 6, and the liquid branch pipes 7a, 7b,
The liquid receiver 14 provided between the branch part 13 of 7c and each liquid branch pipe 7 a t ? Bi-directional throttling mechanism 22a, 22b during b tIc.

Bidirectional flow solenoid valve 15a15 installed in series with 22e
b, 15c, each liquid branch pipe 7a between each solenoid valve 15a, 15b, 15c and connection port 16a, 16b, 16c,
7b, bypass pipes 23 and 24 connecting between 7b and 7c, two-way bypass solenoid valves 25 and 26 provided in the bypass pipes 23 and 24, and a bypass solenoid valve 25 and 26 that connects between 7b and 7c, and a bypass solenoid valve 25 and 26 that connects between 7b and 7c, and Check valves 17a and 17b are provided in a direction that allows refrigerant flow.

The electromagnetic valves 15a, 15b are formed by connecting the apertures 17c and throttles 18a, 18b, and 18c in series, respectively.

Liquid branch pipes 7a, 7b between connection ports 16a, 16b, 16c between 15c and each indoor unit 30a, 30b, 30c
, 7c and the low pressure circuit 20 during heating operation, bypass pipes 19a, 19b, 19c, and gas side branch pipes 8a, 8b, 8c.
Two-way flow solenoid valves 21a and 21 provided therein, respectively.
b, 21 c.

Note that the outdoor unit 1 is equipped with an air blower that blows air to the heat source side heat exchanger 5 at a temperature of .degree.

Further, the indoor units 30a, 30b, and 30c each include user-side heat exchangers 31a, 31b, and 31c, and an indoor blower that sends the air heat-exchanged by each of the user-side heat exchangers 31a, 31b, and 31c into the room.

FIG. 2 shows an embodiment of the electric circuit of the multi-room air conditioner according to the present invention, showing the coil 5vLa of the solenoid valve 15a and the solenoid valve 21.
The coil 5VGa and the electromagnetic switch MRa of a are the operation switch 40a and relay 40 of the indoor unit 30a, respectively.
A is connected in parallel to the power supply 45 via a series-connected circuit, and similarly the coil 5vLb of the solenoid valve 15b and the solenoid valve 21b
Coil 5VGb and electromagnetic switch MRb are each indoor units) Operation switch 40b and relay 46 of 3Qb
Similarly, the coil SVLo of the solenoid valve 15c, the coil 5VGc of the solenoid valve 21c, and the solenoid switch MRo are connected in parallel to the power supply 45 through a circuit in which the It is connected in parallel to the power supply 45 via a circuit in which a relay 46c is connected in series.

In addition, the motor MC of compressor 2 is connected to electromagnetic switches MRa and MRb.
, MRo normally open contacts MRa82MRb8. 'Coils b and vb of the bypass solenoid valves 25 and 26 are connected in series with the circuit in which MRo5 is connected in parallel and connected to the power supply 45, and further connected in parallel.

Relay 43 and coil 41 of four-way valve 4 connected in series with
The operation switch 40 consists of a microcomputer, etc.
ON of a, 40b, 40c.

Relays 43, 46a by detecting OFF.

A control device 44 for controlling 46b and 46c is connected in parallel to a power source 45 via a heating side contact 48 of a heating/cooling changeover switch 42, respectively.

Here, the operation of the multi-room air conditioner according to the present invention having the above configuration during heating operation will be explained.

Now, with the cooling/heating selector switch 42 pushed back to the heating side contact 48 side, the operation switch 4 of the indoor unit 30a
0a is turned on, the control device 44 consisting of a microcomputer etc. detects that the indoor unit 30a has stopped and has issued the first signal to rotate the motor MC of the compressor 2. In order to keep the normally closed contact of the relay 46a closed, voltage is applied to the coils 5vLa and 5vGa of the solenoid valves 15a and 21a and the solenoid switch MRa, and the solenoid valves 15a and 21a are opened and the solenoid switch MR is closed.
The normally open contact MRa8 of is closed to rotate the motor MC of the compressor 2.

At this time, as mentioned earlier, the control device 44 detects that the indoor unit 30a has stopped and has issued the first control signal to rotate the motor MC of the compressor 2.
・Since the normally open contact of the relay 43 is left open, the coils V of the bypass solenoid valves 25 and 26
a~b, vb,.

There is no power. In this way, the coil 41 of the four-way valve 4 is energized and the refrigerant gas discharged from the compressor 2 passes through the four-way valve 4, the gas side main pipe 9, the gas side branch pipe 8a, and the solenoid valve 21a to the indoor unit 30a. The heat is radiated and liquefied to the indoor heat exchanger 31a, and the connection port 16a, solenoid valve 15a, source side branch pipe 7a, expansion device 22a, branch point
3. It passes through the liquid receiver 14, is depressurized by the heating throttle mechanism 11, passes through the low pressure circuit 20 during heating operation, and is transferred to the heat source side heat exchanger 5.
When it evaporates, it passes through the four-way valve 4 again, passes through the accumulator 10, and returns to the compressor 2, forming a refrigeration cycle, and the indoor unit 30a performs heating operation.

In this case, it goes without saying that the outdoor blower and the indoor blower in the indoor unit 30a operate to raise the temperature to .degree.

Also, during heating operation of this indoor unit 30a, other indoor units) 30b.

30C opens the contacts of the operation switches 40b and 40c and returns to ℃, so heating operation is not performed and the solenoid valves 15b and 21
Coils b, 15c, 21c 5VLbSVGb, 5VL
c, 5vGo is energized from L-u' to solenoid valve 1.
5a, 21b, 15c, and 21c close the passages.

Therefore, the refrigeration circuit 32b, which is closed by the solenoid valves 21b and 15b and includes the indoor heat exchanger 31b, and the refrigeration circuit 32c, which is closed by the solenoid valves 21c and 15c and includes the indoor heat exchanger 31c, are in a state where no refrigerant flows. It is in.

However, in reality, the solenoid valves 21a, 21b, 21c, 1
5a, 15b.

Indoor unit 30b, etc., is stopped because the flow of refrigerant cannot be completely stopped and there is some leakage.

The refrigerant gradually accumulates in the indoor heat exchangers 31b and 31c of 30c, resulting in a temperature of ℃.

However, a large amount of refrigerant accumulates in the indoor heat exchangers 31b and 31c (when the indoor unit is in operation), and the amount of refrigerant flowing through the indoor heat exchanger 31a of the indoor unit 30a decreases, resulting in a decrease in heating capacity. There is a problem in trying to imitate a burnout in the compressor 2.

Therefore, the indoor heat exchanger 31C93 is connected to the bypass pipes 19b and 19c, one end of which is connected to the low pressure circuit 20 during heating operation.
Remove the refrigerant that has accumulated in Ib.

Therefore, the refrigerant pressure in the indoor heat exchangers 31b, 31c of the indoor units (30b, 30c) that are stopped is at the same low pressure state as in the low pressure circuit 20' during heating operation, which is .degree.

Under these circumstances, when additionally operating another indoor unit 30b, the conventional control method would open the solenoid valves 21b and 15b at the same time, causing a pressure difference in the low-pressure indoor heat exchanger 3ib. Because the high-pressure refrigerant gas flows at high speed, the refrigerant gas is thick (・refrigerant impact noise and vibration, violent
1b's lunch box noise etc. occurred (・ta).

Therefore, in the case of the present invention, as shown in the valve operation timing chart of FIG.
When the switch b is turned on, the control device 44 consisting of a microcomputer or the like detects that the operation switch 40a has already been turned on (
- It is detected that the operation switch 40b is turned on while the motor MC of the compressor 2 is in operation, and the relay 46b is activated.
Open the normally closed contact of the relay 43 and close the normally open contact of the relay 43 to bypass the coils 8-b and 2b of the bypass solenoid valves 25 and 26.

When voltage is applied to the refrigeration circuit 32, high-pressure liquid flows.
The refrigeration circuits 32b and 32c are connected through the bypass pipes 23 and 24, and the liquid refrigerant enters the refrigeration circuits 32b and 32c.
The pressure at 32c will gradually rise.

Since the refrigerant flowing into the refrigeration circuit 32b through the bypass pipe 24 is in liquid form, the inflow speed is slow and no impact noise is generated.

In this way, the pressure inside the refrigeration circuits 32b and 32c increases to a certain extent, and when the solenoid valve 21b is opened, the indoor heat exchanger 31b
The refrigerant pressure flowing into the chamber, the excess pressure, and the indoor heat exchanger 3Ib
At a point where the pressure difference between the internal pressure and the internal pressure is too large, the control device 44 opens the contact of the relay 43 (Key 1) and closes the normally closed contact of the relay 45b. The coils 5VGbSVLb of the solenoid valves 21b and 15b are energized, and the solenoid valves 21b and 1
5b is opened, the refrigerant flowing through the solenoid valve 21b enters the refrigeration circuit 32b with a small pressure difference (.
Because of this, there is no impact noise or vibration.

In addition, the solenoid valve 21b does not undergo sudden valve opening, so there is no possibility of the valve accumulating at °C.

Bypass solenoid valve 25 provided in this refrigeration circuit
．． Since it is not known which indoor unit will be additionally operated when the indoor unit 26 is operated, for example, it may be inserted into the bypass pipe 24 from the refrigeration circuit 32a side to the refrigeration circuit 32b side, or from the refrigeration circuit 32b side. Since water may flow from the refrigeration circuit 32b side to the refrigeration circuit 32a side, it is necessary to use a solenoid valve with bidirectional flow capability.

In addition, in this embodiment, only two bypass pipes 23°240 are provided (.), but if necessary, the refrigeration circuits 32a and 32
You can also install a third bypass pipe that connects c, and insert a bidirectional solenoid valve in this bypass pipe.

Also, the positions of the bypass pipes are the solenoid valves 15a and 15b.

The source side branch pipes 7a, 7b, 7c between 15c and the connection ports 16a, 16b, 16c are connected to each other and the solenoid valve 15
a, 15b, 15c and the bypass solenoid valves 25.26, if the flow resistance is small, the throttle devices 22a, 22b, 2
2c and solenoid valves 15a and 15b.

It goes without saying that the same effect can be expected even if the source side branch pipes 7a, 7b, and 7c are tied between the tubes 15c and 15c.

Furthermore, in this embodiment, when operating the indoor unit 30c while the indoor unit 30a is operating, the bypass solenoid valve 25,
It is necessary to open both of 26, but indoor unit) 30
When operating the indoor unit 30b during operation a, the electric circuit should be configured such that only the bypass solenoid valve 25 is opened (
・Teyo (・.

Furthermore, in the electric circuit shown in Fig. 2, the operation switch 40 is
If a temperature controller is installed in series with a, 40b, and 40c, and the same control is performed when the operation switch is turned on and the temperature controller is restarted while other indoor units are in operation and compression operation is in progress, the same result will be obtained. You may also get the effect of
It is a fact that there is no horse.

Further, the opening time of the bypass solenoid valves 25 and 26 may be calculated and determined each time by a microcomputer, taking various conditions into account.

That is, the various conditions include various factors such as the number of units in the operating room, thermostat temperature, thermostat metal time, and the like.

Alternatively, the bypass solenoid valve may be controlled by a pressure switch or the like.U-8 As mentioned above, in the multi-room air conditioner according to the present invention, the compressor operates During heating operation, when another indoor unit is restarted by additional heating operation or thermostat, etc., the indoor heat exchanger of the indoor unit that is stopped by bypassing the source side branch pipe on the indoor unit side from the throttle device. After increasing the internal pressure, the gas-side solenoid valve and the source-side solenoid valve are opened (・), which allows quiet heating operation without refrigerant impact noise or vibration from the indoor unit, and also allows for intense heating. This has great effects such as no valve hit of the gas side solenoid valve and the life of the gas side solenoid valve can be extended.

[Brief explanation of drawings]

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 an embodiment of the multi-chamber air conditioner, and Fig. 3 is the operation of the solenoid valve. It is a timing chart figure. 1...Outdoor unit, 7a, 7b, 7c...
... Source side branch pipe, 15a, 15b, 15c-
・=-Solenoid valve, 19a, 19b, 19c... Bypass pipe (liquid drain pipe), 21 a, 2 l b,
21 c = solenoid valve, 22a, 22b, 22c...
-・-Aperture device, 23,2481008. bypass pipe,
25,2610100. Bypass solenoid valve, 30a,
30 b, 30 c-・--・Indoor unit, 4
4...Control device, 43.46a, 46b
, 46c... Relay, MC... Compressor motor, 5VLa. SVI, b, 5VLo -------・Solenoid valve, 15a,
15b. 15e coil, 5VGa, 5VGb, 5VGo...
,,. Coils of solenoid valves 21a, 21b, 21c, va, b...
... Coil of solenoid valve 25, VB, c... Coil of solenoid valve 26.

Claims (1)

[Claims] In a multi-room air conditioner in which a plurality of indoor units are connected to 11 outdoor units by connection piping, the source side main pipe of the outdoor unit is branched to the number of the indoor units. A throttle device and a source-side solenoid valve are connected in series in each of the source-side branch pipes created by The side branch pipes are connected by at least as many bypass pipes that can communicate with each other, and bypass solenoid valves are provided in the bypass pipes, and the gas side main pipe is branched to the number of indoor units, and the gas side is connected to each of the gas side branch pipes. A solenoid valve was provided, and a liquid drain pipe was connected from each of the source side branch pipes between each of the source side solenoid valves and each of the indoor heat exchangers of each of the indoor units to a pipe line that becomes low pressure during heating operation. Multi-room air conditioner. In a multi-room air conditioner in which 21 outdoor units and multiple indoor units are connected by connecting piping, the source-side main pipe of the outdoor unit is connected to the number of indoor units. A throttle device and a source-side solenoid valve are connected in series in each of the branched source-side branch pipes, and the throttle device and the source-side solenoid valve are connected in series between each of the throttle devices and the indoor heat exchanger of each of the plurality of indoor units. Each of the source side branch pipes is connected with at least a number of bypass pipes that can communicate with each other, and a bypass solenoid valve is provided in the bypass pipe, and the gas side main pipe is branched to the number of indoor units to form gas side branch pipes. A gas-side solenoid valve is provided at each of the source-side solenoid valves and each of the source-side branch pipes between each of the indoor heat exchangers of each of the indoor units is provided with liquid drained from each of the source-side branch pipes to the pipes that are at low pressure during heating operation. When the pipes are connected and one or more indoor units are in heating operation and another indoor unit is returned to operation or additional heating operation is performed using a temperature controller, etc., refrigerant is supplied to at least one of the indoor units in heating operation. After the bypass solenoid valve is opened for a certain period of time, the bypass solenoid valve is opened for a certain period of time, so that the source side branch pipe and the other source side branch pipe that connects the temperature controller or the indoor unit of the pre-distribution unit that is to be operated for additional heating are connected. A multi-chamber air conditioner that opens the source side solenoid valve in the source side branch pipe and the gas side solenoid valve in the gas side branch pipe connected to the unit.