JPS6152912B2 - - 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 perform quiet heating operation. It is something.

In a conventional multi-room air conditioner, when the compressor is running and the indoor unit is in heating operation, if another indoor unit is added to perform heating operation, this added indoor The gas-side solenoid valve and liquid-side solenoid valve that control the flow of refrigerant to the indoor heat exchanger of the unit were opened at the same time. However, before the indoor heat exchanger of this additionally operated indoor unit was operated, the flow of refrigerant was stopped by closing the gas side solenoid valve and the liquid side solenoid valve, and the pressure was low. Since the compressor was connected to the existing circuit, the pressure was at a low level, almost the same as the suction pressure of the compressor. Therefore, if the gas-side solenoid valve and the liquid-side solenoid valve are opened simultaneously, high-pressure gas will suddenly flow into the low-pressure indoor heat exchanger, and this flowing refrigerant may cause a loud gurgling noise from the indoor unit. In addition, the valve part of the check valve installed in parallel with the cooling throttle mechanism in the indoor unit is violently pressed against the stopper, causing a clicking sound, and sometimes causing damage to the floor or wall where the indoor unit is installed. However, it also had major problems such as the transmission of vibrations.

The present invention obviates the above-mentioned drawbacks. As a configuration for this purpose, the present invention connects a plurality of indoor units to one outdoor unit, and installs a liquid side electromagnetic pipe in each liquid side branch pipe formed by branching from the liquid side main pipe according to the number of indoor units. A valve is provided, and a slow-motion on/off valve is provided in each gas side branch pipe formed by branching from the gas side main pipe according to the number of indoor units, and each liquid side solenoid valve and each indoor side of the indoor unit are provided with a slow movement valve. A bypass pipe connects the heat exchanger and the refrigerant pipe line, which becomes low pressure during heating operation. One embodiment will be described below based on the drawings.

FIG. 1 is a refrigeration cycle diagram of a multi-chamber air conditioner according to the present invention. Liquid side branch pipes 7a, 7b, 7c formed by branching the main pipe 6 at the branch point 13, liquid side branch pipe 7a,
The same number of gas side branch pipes 8a and 8 as 7b and 7c
b, 8c, a gas side main pipe 9 formed by collecting these gas side branch pipes 7a, 7b, 7c, an accumulator 10, and a heating throttle mechanism 11 provided in the liquid side main pipe 6.
, a check valve 12 provided in parallel with the heating throttle mechanism 11 to block the flow of refrigerant during heating operation, the heating throttle mechanism 11 of the liquid side main pipe 6 and the liquid side branch pipe 7a, Liquid receiver 14 provided between the branch parts 13 of 7b and 7c, and each liquid side branch pipe 7a, 7b, 7c
Two-way flow solenoid valves 15a, 15 provided inside
b, 15c, solenoid valves 15a, 15b, 15c, each made by connecting check valves 17a, 17b, 17c and throttles 18a, 18b, 18c in series, with the low pressure circuit 20 side during heating operation as the flow blocking side. Connection port 16 with indoor units 30a, 30b, 30c
Liquid side branch pipes 7a, 7b between a, 16b, 16c,
7c and the low pressure circuit 20 during heating operation, bypass pipes 19a, 19b, 19c, gas side branch pipe 8a,
8b and 8c, respectively, are comprised of two-way flowable slow-acting on-off valves 21a, 21b, and 21c, respectively. Note that the gradual opening/closing valves 21a, 21b, and 21c are open valves that gradually open when an opening signal is issued. Specifically, for example,
It has the same configuration as the expansion valve known from Publication No. 23335 or Japanese Utility Model Publication No. 32833/1983. In addition, the indoor units 30a, 30b, 30c are connected to the indoor heat exchangers 31a, 31b, 31c, the cooling throttle mechanisms 32a, 32b, 32c, and the refrigerant in parallel with the cooling throttle mechanisms 32a, 32b, 32c during the cooling operation. It consists of check valves 33a, 33b, and 33c provided so as to block the flow of water.

FIG. 2 shows an embodiment of the electric circuit of the multi-room air conditioner according to the present invention, in which the coil of the solenoid valve 15a is shown.
SV _La , the coil SV _Ga of the solenoid valve 21a, and the solenoid switch M _Ra are each connected in parallel to the power supply via the operation switch 40a of the indoor unit 30a, and similarly, the coil SV _Lb of the solenoid valve 15b and the solenoid valve 2
The coil SV _Gb of the solenoid valve 1b and the electromagnetic switch M _Rb are each connected in parallel to the power supply via the operation switch 40b of the indoor unit 30b, and the coil SV _Lc of the solenoid valve 15c, the coil SV _Gc of the solenoid valve 21c,
The electromagnetic switches M _Rc are each connected in parallel to the power source via the operation switch 40c of the indoor unit 30c.

In addition, the motor MC of the compressor 2 has an electromagnetic switch MR _a ,
The normally open contacts MR _as , MR _bs , MR _cs of MR _b and MR c are connected in series to the power supply, and the coil 41 of the four-way valve ₄ is connected to the heating side contact of the cooling/heating changeover switch 42. Connected to power via.

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 that the cooling/heating selector switch 42 is turned to the heating side, voltage is applied to the coil 41 of the four-way valve 4, and the operation switch 40 of the indoor unit 30a is turned on.
Contact a closes, contact of electromagnetic switch MR _a closes, motor MC of compressor 2 rotates, and coil
Assume that since voltage is applied to SV _Ga and SV _La , the passages of the slow-moving on-off valve 21a and the solenoid valve 15a are opened, and only the indoor unit 30a is in heating operation. In this state, first, the refrigerant discharged from the compressor 2 passes through the compressor 2, the discharge muffler 3, and the four-way valve 4, and reaches each gas side branch pipe 8a, 8b, 8c. Here, the passage of the gradual movement on-off valve 21a is opened and the passages of the other gradual movement on-off valves 21b and 21c are closed, so the refrigerant is sent only to the indoor unit 30a, and the indoor heat exchanger 31a and the check valve 33a. It enters the outdoor unit 1 again through the liquid side branch pipe 7a, and the solenoid valve 15 in the liquid side branch pipe 7a
a, passes through the branch point 13 and receiver 14, is depressurized by the heating throttle mechanism 11, evaporates in the outdoor heat exchanger 5, passes through the four-way valve 4 again, passes through the accumulator 10, and returns to the compressor 2. In addition, gradual opening/closing valves 21a, 21b and solenoid valves 15b, which control the flow of refrigerant in the indoor units 30b, 30c whose operation is stopped or stopped,
Since 15c is closed, the gradual opening/closing valve 21b
and a refrigeration circuit that is closed by the solenoid valve 15b and includes the indoor heat exchanger 31b, and the indoor heat exchanger 3 that is closed by the deactivation on-off valve 21c and the solenoid valve 15c.
Refrigerant does not flow into the refrigeration circuit including 1c. However, in reality, the gradual opening/closing valves 21a, 21b, 2
1c, solenoid valves 15a, 15b, 15c, etc. cannot completely stop the flow of refrigerant and may leak. Therefore, refrigerant gradually accumulates in the indoor heat exchangers 31b, 31c of the indoor units 30b, 30c that are stopped. However, the indoor heat exchanger 31
If a large amount of refrigerant accumulates in b and 31c, the amount of refrigerant flowing through the indoor heat exchanger 31a of the indoor unit 30a during operation will decrease, resulting in a decrease in heating capacity and causing damage to the compressor 2. become. Therefore, the refrigerant accumulated in the indoor heat exchangers 31b, 31c is extracted by bypass pipes 19b, 19c, one end of which is connected to the low pressure circuit 20 during heating operation. Therefore, the indoor heat exchangers 31b, 31 of the indoor units 30b, 30c that are stopped
The refrigerant pressure in c is in the same low pressure state as in the low pressure circuit 20 during heating operation.

When additional heating operation is performed on the other indoor unit 30b under such circumstances, the conventional control method simultaneously opens the solenoid valve provided in place of the gradual opening/closing valve 21b and the solenoid valve 15b. High-pressure refrigerant suddenly flowed into the indoor heat exchanger 31b, causing loud refrigerant noise and vibrations.

Therefore, in the case of the present invention, when the operation switch 40b of the indoor unit 30b is turned on, voltage is applied to the coil SV _Gb of the solenoid valve 15b and the coil SV _L of the slow-acting on-off valve 21b, and the passage of the solenoid valve 15b in the liquid side branch pipe 7b is closed. By opening the refrigerant, a part of the high-pressure refrigerant that has been flowing through the indoor heat exchanger 31a of the indoor unit 30a that has been in operation to the solenoid valve 15a, the branch point 13, and the liquid receiver 14 is transferred from the branch point 13 to the electromagnetic refrigerant. valve 15b,
The indoor heat exchanger 3 passes through the cooling throttle mechanism 32b.
1b, and at the same time, during this time, the gradual opening/closing valve 21
By gradually increasing the opening degree of the valve b, the refrigerant is gradually transferred from the gas side branch pipe 8b side to the indoor heat exchanger 3.
1b to bring the indoor heat exchanger 31b into a high pressure state. Here, since the cooling throttle mechanism 32b has a large resistance, the pressure inside the indoor heat exchanger 31b gradually increases, and the gradual opening/closing valve 21b is operated by a coil.
Initially, when voltage is applied to SV _Gb , the valve opening is small, so refrigerant does not suddenly flow into the indoor heat exchanger 31b, and no noise or vibration is generated.

Therefore, this method has the great effect of eliminating the need to generate refrigerant noise that occurs when the indoor unit 30b is additionally operated in the conventional method. In particular, in recent years, electronic control such as a microcomputer has made fine control possible, and solenoid valves 15a, 15
b, 15c, and the solenoid valves in the gas side branch pipes 8a, 8b, and 8c are also being opened and closed frequently, so the conventional method would constantly generate noise and vibration, making it difficult to achieve the effects of the present invention. Especially expected. Furthermore, since the check valve connected in parallel with the cooling throttle mechanism is not suddenly opened or closed, it also has the effect of lengthening its life.

Furthermore, although this embodiment has been explained in the case where additional heating operation is performed, the same effects can be obtained when an indoor unit whose heating operation is suspended due to the temperature controller is restarted by the temperature controller. Needless to say.

Next, the cooling operation will be briefly explained. now,
Assuming that only the indoor unit 30a is operating, the refrigerant leaving the compressor 2 is distributed to the discharge muffler 3, the four-way valve 4, the outdoor heat exchanger 5, the check valve 12, the solenoid valve 15a, and the cooling throttle mechanism 32a. , the indoor heat exchanger 31a, the gradual opening/closing valve 21a, the four-way valve 4, and the accumulator 10 before returning to the compressor 2, and the cycle is repeated. In this case, when operating the indoor unit 30b, the solenoid valve 15 is turned on by turning on the operation switch 40b.
b, the gradual opening/closing valve 21b opens, and the refrigerant flows into the indoor heat exchanger 31b. In this case, the gradual opening/closing valve 2
1b is gradually opened, but the indoor heat exchanger 31b
Since the refrigerant flowing into the air conditioner is throttled by the cooling throttle mechanism 32b and gradually flows into the air conditioner, no vibration or noise is generated.

In this embodiment, although not shown, the blowers provided in the outdoor unit 1 and the indoor units 30a, 30b, and 30c, respectively, are present, and are activated by turning on the operation switch 40a, 40b, or 40c.

As mentioned above, the multi-chamber air conditioner according to the present invention has the following features:
When one or more indoor units are in heating operation and the compressor is running, when operating a stopped indoor unit, the solenoid valve in the liquid side branch pipe is opened and the gas side branch pipe is slowly opened/closed at the same time. Since the valve is opened gradually, the refrigerant pressure in the heat exchanger of the operated indoor unit gradually rises, and the indoor unit does not generate noise and vibration, allowing extremely quiet heating operation. This has the great effect of extending the life of the check valve installed in the indoor unit.

[Brief explanation of the drawing]

FIG. 1 is a refrigeration cycle diagram of a multi-chamber air conditioner according to an embodiment of the present invention, and FIG. 2 is an electrical circuit diagram of essential parts of the multi-chamber air conditioner. 1...Outdoor unit, 7a, 7b, 7c...Liquid side branch pipe, 8a, 8b, 8c...Gas side branch pipe, 15
a, 15b, 15c...Solenoid valve, 19a, 19
b, 19c...Bypass pipe, 21a, 21b, 2
1c... Gradual opening/closing valve, 30a, 30b, 30c...
...Indoor unit, 31a, 31b, 31c...Indoor heat exchanger.

Claims (1)

[Claims] 1 One outdoor unit having a compressor, a four-way valve, a heating throttle mechanism, a check valve that bypasses the heating throttle mechanism during cooling operation, and a liquid receiver, an indoor heat exchanger, Each indoor unit is formed by connecting a plurality of indoor units each having a cooling throttle mechanism and a check valve that bypasses the cooling throttle mechanism during heating operation, and branching from the liquid side main pipe according to the number of indoor units. A liquid-side solenoid valve is provided in each of the liquid-side branch pipes, and a gas-side slow-motion on-off valve that gradually opens is provided in each of the gas-side branch pipes formed by branching from the gas-side main pipe according to the number of indoor units, Furthermore, the refrigerant pipes between each of the liquid-side solenoid valves and each of the indoor heat exchangers of the indoor unit, and between the heating throttle mechanism and the outdoor heat exchanger, which have low pressure during heating operation, are bypassed. A multi-room air conditioner that is connected by a pipe, and in which a check valve and a resistor are connected in series to the bypass pipe to block the flow of refrigerant from the refrigerant pipe, which becomes low pressure during heating, to the liquid side branch pipe.