JPH07174427A - Multiroom cooling heating device - Google Patents

Abstract

PURPOSE:To prevent a refrigerant flowing in a refrigerant conveying device from being brought into a two-phase by providing a detecting means for an indoor unit and a conveying device and providing a drive means for causing the start of cooling operation of a stop outdoor unit based on output signals from an outdoor unit and a means for measuring a refrigerant circulating amount. CONSTITUTION:It is judged by an operation output door unit deciding means 21 based on an output signal from an operation outdoor unit detecting means 18 which outdoor units K or K' is under operation. Further, it is judged by a refrigerant amount deciding means 22 based on output signals from a conveying device pressure detecting means 19 and an outdoor unit pressure detecting means 20 whether or not a refrigerant circulation amount is in short supply. Based on output signals from the operation outdoor unit means 21 and the refrigerant amount deciding means 22, the outdoor unit K or K' under a stop is caused to start cooling operation by a drive means 23. As a result, though the outdoor units K and K' under cooling operation is situated in a position lower than that of a refrigerant conveying device 12, a refrigerant flowing in the refrigerant conveying device 12 is prevented from being brought into a two- phase.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-chamber cooling / heating apparatus in which heat is exchanged between a heat source side refrigerant cycle and a user side refrigerant cycle, and more particularly to control during cooling operation.

[0002]

2. Description of the Related Art As a conventional technique, Japanese Patent Laid-Open No. 3-2365 is known.
There is a multi-room air conditioner as known from Japanese Patent No. 36.

A conventional technique will be described below with reference to the drawings. FIG. 5 shows a refrigeration cycle diagram of a conventional multi-room air conditioner.

In FIG. 5, 1a and 1b are compressors and 2
a, 2b are four-way valves, 3a, 3b are heat source side heat exchangers, 4
a and 4b are expansion valves for cooling, 5a and 5b are expansion valves for heating,
6a and 6b are check valves that close the cooling expansion valves 4a and 4b during heating, and 7a and 7b are heating expansion valves 5a and 5 during cooling.
The check valves 8a and 8b for closing b are first auxiliary heat exchangers, which are connected in an annular shape to form a heat source side refrigerant cycle.

Reference numerals 9a and 9b denote second auxiliary heat exchangers, which are integrally formed so as to exchange heat with the first auxiliary heat exchangers 8a and 8b. Refrigerant amount adjusting tanks 10a and 10b adjust the amount of refrigerant during cooling and during heating. 11a, 11
Reference numeral b denotes an outdoor flow valve, which adjusts the refrigerant flow rate of the second auxiliary heat exchangers 9a and 9b. Reference numeral 12 denotes a refrigerant transporting device, which has a reversible characteristic that the outflow directions of the refrigerant are opposite during cooling and during heating, and is provided in the middle of the connecting pipe i which is a multi-liquid pipe.

Reference numerals 13a and 13b are heat exchangers on the use side.
14a and 14b are indoor flow rate valves, and are used side heat exchangers 1
The refrigerant flow rates of 3a and 13b are adjusted. Utilization side heat exchanger 1
3a, 13b and indoor flow valves 14a, 14b are housed in indoor units g, g '.

The second auxiliary heat exchangers 9a, 9b, the refrigerant amount adjusting tanks 10a, 10b, the outdoor flow valves 11a, 11b, the refrigerant transfer device 12, the use side heat exchangers 13a, 13b, the indoor flow valves 14a, 14b and the connection. Piping i, i ', j,
j'is connected in a ring to form a utilization side refrigerant cycle.

The operation of the multi-room cooling and heating apparatus configured as described above will be described. First, during cooling operation, FIG.
In the refrigerant cycle indicated by the solid line arrow, the high-temperature high-pressure gas compressed by the compressors 1a, 1b passes through the four-way valves 2a, 2b and radiates heat in the heat-source side heat exchangers 3a, 3b to be condensed and liquefied. Through the check valves 6a and 6b, the pressure is reduced by the cooling expansion valves 4a and 4b, and the first auxiliary heat exchangers 8a and 8b
endothermic vaporization at b, passing through the four-way valves 2a and 2b, the compressor 1
It circulates to a and 1b.

At this time, the second auxiliary heat exchangers 9a, 9b and the first auxiliary heat exchangers 8a, 8b of the use side refrigerant cycle exchange heat, and the refrigerant in the use side refrigerant cycle is cooled and liquefied.
Then, it is sent to the refrigerant transfer device 12 through the refrigerant amount adjusting tanks 10a and 10b and the outdoor flow valves 11a and 11b.

The liquid refrigerant carried out by the refrigerant carrier 12 passes through the connecting pipes i and j, and the indoor flow valves 14a and 14b,
It is sent to the use side heat exchangers 13a and 13b and endothermically evaporated,
It gasifies and circulates through the connecting pipes i ′ and j ′ to the second auxiliary heat exchangers 9a and 9b.

Next, during the heating operation, the refrigerant cycle shown by the broken line arrow in FIG. 5 is performed, and in the heat source side refrigerant cycle, the compressor 1 is used.
The high-temperature high-pressure gas compressed by a and 1b is the four-way valve 2a and 2b.
And is sent to the first auxiliary heat exchangers 8a and 8b and radiates heat to be condensed and liquefied. Then, the pressure is reduced by the heating expansion valves 5a, 5b through the check valves 7a, 7b, and the heat source side heat exchanger 3a,
Endothermic evaporation at 3b passes through the four-way valves 2a and 2b, and the compressor 1
It circulates to a and 1b.

At this time, the second auxiliary heat exchangers 9a, 9b and the first auxiliary heat exchangers 8a, 8b of the use side refrigerant cycle exchange heat with each other, and the refrigerant in the use side refrigerant cycle is heated and gasified.
The gasified refrigerant passes through the connection pipes i ′ and j ′ and is sent to the use side heat exchangers 13a and 13b to be heated and condensed and liquefied, and passes through the indoor flow valves 14a and 14b and the connection pipes i and j. And is sent to the refrigerant transport device 12.

The liquid refrigerant carried out by the refrigerant carrier device 12 has outdoor flow valves 11a and 11b and a refrigerant amount adjusting tank 10.
It circulates to the 2nd auxiliary heat exchangers 9a and 9b through a and 10b.

[0014]

However, in the above configuration, the liquid carrier pump is used as the refrigerant carrier device,
When the outdoor unit in operation and the outdoor unit in stop are mixed in the cooling operation, when the outdoor unit in operation is installed at a position lower than the refrigerant transfer device (for example, as shown in FIG. 5, the refrigerant transfer device and the outdoor unit are not installed). When there is a height difference of 3 m between the units), a pressure loss corresponding to the pressure head is generated, and the refrigerant flowing into the refrigerant transfer device is likely to be in two phases.

When the two-phase is remarkably formed, that is, when the degree of dryness of the refrigerant is high, the refrigerant conveying device is close to the gas conveying state, the refrigerant circulation amount of the use side refrigerant cycle is remarkably reduced, and the refrigerant is in a shortage state, and the cooling capacity is reduced. It had a problem of decreasing.

The present invention solves the above problem and prevents the refrigerant flowing into the refrigerant transfer device from becoming two-phase even when the outdoor unit in operation in the cooling operation is installed at a position lower than the refrigerant transfer device. However, it is an object of the present invention to provide a multi-room cooling / heating apparatus that can secure a cooling capacity in the use-side refrigerant cycle and can always secure a cooling capacity.

[0017]

In order to achieve this object, a multi-room cooling and heating system of the present invention comprises a driving outdoor unit detecting means for detecting that a plurality of outdoor units are in operation,
A transfer device pressure detection unit that is located between the plurality of outdoor flow valves and the refrigerant transfer device to detect the refrigerant pressure in the vicinity of the refrigerant transfer device, and each outdoor flow rate that is located between the plurality of outdoor flow valves and the refrigerant transfer device. An outdoor unit pressure detecting means for detecting the refrigerant pressure in the vicinity of the valve, an operating outdoor unit determining means for determining which outdoor unit is operating based on the output signal of the operating outdoor unit detecting means, and a transfer device pressure detecting means. Refrigerant amount determination means for determining whether the refrigerant circulation amount is insufficient based on the output signal of the outdoor unit pressure detection means, and cooling operation for the stopped outdoor unit based on the output signals of the operating outdoor unit determination means and the refrigerant amount determination means. It is configured to have a driving means for starting.

Further, the operating outdoor unit detection means for detecting that the plurality of outdoor units are in operation, and the refrigerant pressure in the vicinity of the refrigerant transfer device, which is located between the plurality of outdoor flow valves and the refrigerant transfer device, are detected. Based on the output signals of the transfer device pressure detection means, the transfer device temperature detection means located between the plurality of outdoor flow valves and the refrigerant transfer device to detect the refrigerant temperature in the vicinity of the transfer device, and the output signal of the operating outdoor unit detection means. An operating outdoor unit determining means for determining which outdoor unit is operating, a supercooling degree calculating means for calculating a refrigerant supercooling degree based on output signals of the conveying device pressure detecting means and the conveying device temperature detecting means, and A refrigerant amount determination means for determining whether the refrigerant circulation amount is insufficient based on the output signal of the supercooling degree calculation means,
The stop outdoor unit is provided with drive means for starting the cooling operation based on the output signals of the operating outdoor unit determining means and the refrigerant amount determining means.

[0019]

According to the present invention, with the above-mentioned structure, the outdoor unit in the cooling operation is detected by the outdoor unit detecting means,
The refrigerant pressure at the inlet of the refrigerant transfer device is detected by the transfer device pressure detection means, and the refrigerant pressure at the outdoor flow valve outlet is detected by the outdoor unit pressure detection means. Then, the operating outdoor unit determining means determines whether all the outdoor units are operating, and when the operating unit and the stop unit are mixed, the refrigerant amount determining means determines the refrigerant pressure at the inlet of the refrigerant transfer device and the outdoor flow rate valve. Based on the refrigerant pressure at the outlet, it is determined whether or not the refrigerant circulation amount of the usage-side refrigerant cycle is insufficient.

When the refrigerant circulation amount is insufficient, the stop outdoor unit is cooled by the drive means to prevent the refrigerant flowing into the refrigerant transfer device from becoming two-phase.

Further, the outdoor unit during the cooling operation is detected by the operating outdoor unit detecting means, the refrigerant pressure at the refrigerant conveying device inlet is detected by the conveying device pressure detecting means, and the refrigerant at the refrigerant conveying device inlet is detected by the conveying device temperature detecting means. Detect the temperature.

Then, the operating outdoor unit determining means determines whether or not all the outdoor units are operating, and when the operating units and the stopping units are mixed, the supercooling degree calculating means determines the refrigerant pressure at the inlet of the refrigerant transfer device. And the refrigerant supercooling degree is calculated based on the refrigerant temperature.

Then, the refrigerant amount judging means judges whether or not the refrigerant circulation amount of the user side refrigerant cycle is insufficient based on the refrigerant pressure at the inlet of the refrigerant carrier and the degree of refrigerant supercooling.

When the refrigerant circulation amount is insufficient, the stop outdoor unit is cooled by the driving means to prevent the refrigerant flowing into the refrigerant transfer device from becoming two-phase.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a refrigerant cycle diagram of the multi-room cooling and heating apparatus according to the first embodiment. It should be noted that the same components as those of the related art are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, reference numerals 15a and 15b are microcomputers mounted on the outdoor units k and k ', and give a signal whether the outdoor units k and k'are in the cooling operation. 16
Reference numerals a and 16b are first pressure sensors installed at the outlets of the outdoor flow valves 11a and 11b during the cooling operation. Reference numeral 17 is a second pressure sensor installed at the inlet of the refrigerant transfer device 12 during the cooling operation.

Reference numeral 18 is a unit for detecting a unit outside the cab,
The output signals of the microcomputers 15a and 15b are detected. 19 is a conveying device pressure detection means, which detects the output value of the second pressure sensor 17. Reference numeral 20 denotes an outdoor unit pressure detecting means, which detects output values of the first pressure sensors 16a and 16b.

Reference numeral 21 denotes a unit outside the cab for judging the unit,
Based on the output signal of the outdoor unit detecting means 18, it is determined whether the outdoor units k and k'are in operation. Reference numeral 22 denotes a refrigerant amount determination means, which determines whether or not the refrigerant circulation amount in the use side refrigerant cycle is insufficient based on the output values of the first pressure sensors 16a and 16b and the second pressure sensor 17.

Reference numeral 23 is a drive means, which is an outdoor flow valve 11a (or 11b) of the stop outdoor unit k (or k ') and a cooling expansion valve 4a when the refrigerant circulation amount is insufficient.
(Or 4b), a heating expansion valve 5a (or 5b), a four-way valve 2a (or 2b), and a compressor 1a (or 1b) to start a cooling operation.

Reference numeral 24 denotes a control device, which is a unit 18 for detecting a unit outside a driving room, a unit 19 for detecting a pressure of a transfer device, a unit 20 for detecting a pressure outside a unit, a unit 21 for judging a unit outside a driving room,
It is composed of a refrigerant amount determination means 22 and a drive means 23.

The operation of the multi-room cooling and heating apparatus configured as described above will be described. The operation during the normal cooling and heating operation is the same as that of the conventional example, and here, the operation during the cooling operation, which is particularly problematic, will be described with reference to FIG.

In FIG. 2, step 1 is an outdoor unit detecting means 18, which detects the output signals of the microcomputers 15a and 15b mounted on the outdoor units k and k ', and shifts to step 2. Step 2 is the transfer device pressure detection means 19, which detects the output value of the second pressure sensor 17, that is, the refrigerant transfer device 12 inlet pressure Ps, and then
Move to p3. Step 3 is the outdoor unit pressure detection means 20, and is the output value of the first pressure sensor 16a, 16b, that is, the outdoor flow rate valve 11a, 11b outlet pressure Pk, P.
Detects k ′ and shifts to step 4.

Step 4 is a unit outside the cab unit determining means 2
1 and based on the output signal of the outdoor unit detection means 18, k: operation AND k ': not operation, that is, when it is determined that the outdoor unit k, k'includes a combination of operation unit and stop unit Has
Move to step 5.

Step 5 is also the unit outside the cab unit judging means 2
1 and k: when operating, that is, when it is determined that the outdoor unit k is operating, the process proceeds to step 6.

Step 6 is the refrigerant amount determination means 22, and in the case of Ps <P (for example, P = 0.45 MPa) Pk-Ps> p (for example, p = 0.1 MPa), that is, the refrigerant transfer device 12 inlet pressure Ps. Is smaller than the specified value and the pressure difference between the outdoor flow valve 11a outlet pressure Pk and the refrigerant transfer device 12 inlet pressure Ps is larger than the specified value, the refrigerant flowing into the refrigerant transfer device 12 is two-phase, and the refrigerant circulation It is judged that the amount is insufficient, and step7
Move to.

Step 7 is a driving means 23, which opens the outdoor flow valve 11b, opens the cooling decompression device 4b, closes the heating expansion valve 5b, turns off the four-way valve 2b, and sends a signal to operate the compressor 1b. Then, the outdoor unit k ′ starts the cooling operation.

When it is determined in step 6 that the refrigerant circulation amount is not insufficient, the process returns to step 1.

In step 5, if k: not in operation, that is, if it is determined that the outdoor unit k'is in operation, the process proceeds to step 8.

Step 8 is the refrigerant amount determining means 22, and in the case of Ps <P (for example, P = 0.45 MPa) Pk'-Ps> p (for example, p = 0.1 MPa), that is, the refrigerant transfer device 12 inlet pressure. When Ps is smaller than the specified value and the pressure difference between the outdoor flow valve 11b outlet pressure Pk ′ and the refrigerant transfer device 12 inlet pressure Ps is larger than the specified value, the refrigerant flowing into the refrigerant transfer device 12 is two-phase, If it is determined that the refrigerant circulation amount is insufficient, step
Move to 9.

Step 9 is a driving means 23, which outputs a signal to open the outdoor flow valve 11a, open the cooling expansion valve 4a, close the heating expansion valve 5a, turn off the four-way valve 2a, and operate the compressor 1a. Then, the cooling operation of the outdoor unit k is started.

If it is determined in step 8 that the refrigerant circulation amount is not insufficient, the process returns to step 1.

When it is determined in step 4 that both the outdoor units k and k'are in operation, the process proceeds to step 10. Step 10 is a return determination condition, and in the case of Pk-Ps> p (for example, p = 0.1 MPa) AND Pk'-Ps> p (for example, p = 0.1 MPa), that is, the outlet pressures of the outdoor flow valves 11a and 11b. P
When the pressure difference between k and Pk ′ and the inlet pressure Ps of the refrigerant transfer device 12 is larger than the specified value, it is determined that the refrigerant circulation amount is still insufficient, and the process returns to step 1.

At step 10, if Pk-Ps <p (for example, p = 0.1 MPa) AND Pk'-Ps <p (for example, p = 0.1 MPa), that is, the outlet pressures P of the outdoor flow valves 11a and 11b.
When the pressure difference between k and Pk ′ and the inlet pressure Ps of the refrigerant transfer device 12 is smaller than the specified value, it is determined that the refrigerant circulation amount is secured, and the normal cooling operation is resumed.

According to the first embodiment, the refrigerant flowing into the refrigerant carrying device 12 under the condition that the outdoor unit k '(or k) in the cooling operation is installed at a position lower than the refrigerant carrying device 12 or the like. 2 becomes two-phase and the circulating amount of the refrigerant is insufficient, the stop outdoor unit k (or k ′) is caused to start the cooling operation, and the condensation of the refrigerant is promoted.

As a result, it is possible to prevent the refrigerant at the inlet of the refrigerant transfer device 12 from becoming two-phase, to secure the refrigerant circulation amount in the user side refrigerant cycle, and to always ensure the cooling capacity.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a refrigerant cycle diagram of the multi-room cooling and heating apparatus in the second embodiment. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 3, l and l'denominate outdoor units. A thermistor 25 detects the refrigerant temperature at the inlet of the refrigerant transfer device 12 during the cooling operation. Reference numeral 26 is a conveying device temperature detecting means, which detects the output value of the thermistor 25. Reference numeral 27 denotes a subcooling degree calculating means, and the second pressure sensor 1
Based on the output value of 7 and the output value of the thermistor 25, the degree of refrigerant supercooling at the inlet of the refrigerant transfer device 12 during the cooling operation is calculated.

Numeral 28 is a refrigerant quantity judging means, and judges whether or not the refrigerant circulation quantity in the utilization side refrigerant cycle is insufficient based on the output value of the second pressure sensor 17 and the output value of the supercooling degree calculating means 27. .

Reference numeral 23 is a driving means, and when the refrigerant circulation amount is insufficient, the outdoor flow rate valve 11a (or 11b) of the stop outdoor unit 1 (or 1 ') and the cooling expansion valve 4a.
(Or 4b), a heating expansion valve 5a (or 5b), a four-way valve 2a (or 2b), and a compressor 1a (or 1b) to start a cooling operation.

Reference numeral 29 is a control device, which is a unit 18 for detecting a unit outside the driving room, a pressure detecting unit 19 for a conveying unit, a temperature detecting unit 26 for a conveying unit, a unit judging unit 21 outside the driving chamber, a supercooling degree calculating unit 27, a refrigerant amount judging unit 28. , Driving means 23
It consists of

The operation of the multi-room cooling / heating apparatus configured as described above will be described. The operation during the normal cooling / heating operation is the same as that of the conventional example, and here, the operation different from that of the first embodiment during the cooling operation, which is a particular problem, will be described with reference to FIG.

In FIG. 4, step 3 is the conveying device temperature detecting means 26, which detects the output value of the thermistor 25, that is, the temperature Ts at the inlet of the refrigerant conveying device 12, and then detects step 4
Move to.

Step 4 is the unit 2 outside the cab
1 and based on the output signal of the outdoor unit detecting means 18: l: operation AND l ': not operation, that is, when it is determined that the outdoor unit l, l'includes both operating and stopping units Has
Move to step 5.

Step 5 is a supercooling degree calculating means 27, which is provided with the refrigerant transfer device 12 inlet pressure Ps and the refrigerant transfer device 12.
Based on the inlet temperature Ts, the refrigerant supercooling degree Tk at the inlet of the refrigerant transfer device 12 is calculated, and the process proceeds to step 6.

Step 6 is the refrigerant amount determining means 28, and in the case of Ps <P (for example, P = 0.45 MPa) AND Tk <T (for example, T = 1K), that is, the refrigerant transfer device 12 inlet pressure Ps is a prescribed value. When it is smaller and the refrigerant supercooling degree Tk at the inlet of the refrigerant transfer device 12 is smaller than the specified value, it is determined that the refrigerant flowing into the refrigerant transfer device 12 has two phases and the amount of refrigerant circulation is insufficient. , Step 7 is performed.

Step 7 is a unit 2 for judging the unit outside the cab
1 and: l: when stopped, that is, when it is determined that the outdoor unit 1 is stopped, the process proceeds to step 8.

Step 8 is a drive means 23, which outputs a signal to open the outdoor flow valve 11a, open the cooling expansion valve 4a, close the heating expansion valve 5a, turn off the four-way valve 2a, and operate the compressor 1a. Then, the cooling operation of the outdoor unit 1 is started.

In step 7, l: if not stopped, that is, if it is determined that the outdoor unit 1 is in operation, the process proceeds to step 9.

Step 9 is a driving means 23, which outputs a signal to open the outdoor flow valve 11b, open the cooling expansion valve 4b, close the heating expansion valve 5b, turn off the four-way valve 2b, and operate the compressor 1b. Then, the cooling operation of the outdoor unit 1'is started.

If it is determined in step 6 that the refrigerant circulation amount is not insufficient, the process returns to step 1.

When it is determined in step 4 that both the outdoor units l and l'are in operation, the process proceeds to step 10. Step 10 is a return determination condition, and when Tk <T (for example, T = 1K), that is, the refrigerant supercooling degree T at the inlet of the refrigerant transfer device 12
If k is smaller than the specified value, it is determined that the refrigerant circulation amount is still insufficient, and the process returns to step 1.

In step 10, if Tk> T (for example, T = 1K), that is, the refrigerant supercooling degree T at the inlet of the refrigerant transfer device 12
When k is larger than the specified value, it is determined that the refrigerant circulation amount is secured, and the normal cooling operation is resumed.

According to the second embodiment, the refrigerant that flows into the refrigerant carrier 12 under the condition that the outdoor unit 1 '(or 1) in the cooling operation is installed at a position lower than the refrigerant carrier 12. 2 becomes a two-phase and the circulating amount of the refrigerant is insufficient, the stop outdoor unit 1 (or 1 ′) is caused to start the cooling operation, and the condensation of the refrigerant is promoted.

As a result, it is possible to prevent the refrigerant at the inlet of the refrigerant transfer device 12 from becoming two-phase, to secure the refrigerant circulation amount in the user side refrigerant cycle, and to always ensure the cooling capacity.

Further, since one pressure sensor can be eliminated for each outdoor unit, the cost can be reduced.

[0066]

As is apparent from the above description, according to the present invention, there is provided between the operation outdoor unit detection means for detecting that the plurality of outdoor units are in operation, and the plurality of outdoor flow valves and the refrigerant transfer device. A transfer device pressure detection means for detecting the refrigerant pressure in the vicinity of the refrigerant transfer device, and an outdoor unit pressure detection for detecting the refrigerant pressure in the vicinity of each outdoor flow valve located between the plurality of outdoor flow valves and the refrigerant transfer device. Means, and an outdoor unit determining means for determining which outdoor unit is operating based on the output signals of the outdoor unit detecting means, and a refrigerant based on the output signals of the carrier device pressure detecting means and the outdoor unit pressure detecting means. Refrigerant amount determining means for determining whether or not the circulation amount is insufficient, and drive means for causing the stopped outdoor unit to start cooling operation based on the output signals of the operating outdoor unit determining means and the refrigerant amount determining means. Obtain.

As a result, even when the outdoor unit during the cooling operation is installed at a position lower than the refrigerant transporting device, the refrigerant flowing into the refrigerant transporting device is prevented from being two-phased and the refrigerant circulation in the use side refrigerant cycle. It is possible to provide a multi-room cooling and heating device that can secure a sufficient amount of air conditioning capacity at all times.

Further, according to the present invention, the operating outdoor unit detecting means for detecting that the plurality of outdoor units are in operation, and the refrigerant pressure in the vicinity of the refrigerant carrying device located between the plurality of outdoor flow valves and the refrigerant carrying device. An output signal of the transfer device pressure detection means for detecting the temperature, a transfer device temperature detection means for detecting the refrigerant temperature in the vicinity of the refrigerant transfer device, which is located between the plurality of outdoor flow valves and the refrigerant transfer device, and an operating outdoor unit detection means. A sub-cooling degree calculating means for calculating a refrigerant sub-cooling degree based on the output signals of the operating-outdoor unit determining means for determining which outdoor unit is operating based on And a refrigerant amount judging means for judging whether the refrigerant circulation amount is insufficient based on the output signal of the supercooling degree calculating means, and stopping based on the output signals of the operator outside unit judging means and the refrigerant amount judging means A driving means for starting the cooling operation outside unit.

As a result, even when the outdoor unit during the cooling operation is installed at a position lower than the refrigerant transfer device, the refrigerant flowing into the refrigerant transfer device is prevented from being two-phased, and the refrigerant circulation in the use-side refrigerant cycle is prevented. It is possible to provide a multi-room cooling and heating device that can secure a sufficient amount and can always secure the cooling capacity and can reduce the cost.

[Brief description of drawings]

FIG. 1 is a refrigerant cycle diagram of a multi-room cooling and heating apparatus according to a first embodiment of the present invention.

FIG. 2 is an operation flowchart during a cooling operation of the multi-room cooling and heating apparatus according to the first embodiment of the present invention.

FIG. 3 is a refrigerant cycle diagram of the multi-room cooling and heating apparatus according to the second embodiment of the present invention.

FIG. 4 is an operation flowchart during a cooling operation of the multi-room cooling / heating apparatus according to the second embodiment of the present invention.

FIG. 5: Refrigerant cycle diagram of a conventional multi-room air conditioner

[Explanation of symbols]

 1a, 1b Compressor 3a, 3b Heat source side heat exchanger 4a, 4b Cooling expansion valve 5a, 5b Heating expansion valve 8a, 8b First auxiliary heat exchanger 9a, 9b Second auxiliary heat exchanger 11a, 11b Outdoor flow rate Valve 12 Refrigerant transfer device 13a, 13b User side heat exchanger 18 Operating outdoor unit detection means 19 Transfer device pressure detection means 20 Outdoor unit pressure detection means 21 Operating outdoor unit determination means 22 Refrigerant amount determination means 23 Driving means 26 Transfer device temperature detection Means 27 Supercooling degree calculating means 28 Refrigerant amount judging means k, k'Outdoor unit l, l'Outdoor unit

Claims (2)

[Claims] 1. A heat source side refrigerant cycle formed by annularly connecting a compressor, a heat source side heat exchanger, a cooling expansion valve, a heating expansion valve and a first auxiliary heat exchanger, and the first auxiliary heat exchanger. A plurality of outdoor units having a second auxiliary heat exchanger integrally formed with the second auxiliary heat exchanger, and an outdoor flow valve provided in series with the second auxiliary heat exchanger; and a plurality of outdoor units provided in each of the outdoor units. Detecting that the second auxiliary heat exchanger, the outdoor flow valve, a plurality of usage-side heat exchangers, and a usage-side refrigerant cycle in which the refrigerant transfer device is connected in an annular shape, and a plurality of the outdoor units are in operation An operating outdoor unit detecting means, a conveying device pressure detecting means for detecting a refrigerant pressure in the vicinity of the refrigerant conveying device, which is located between the plurality of outdoor flow valves and the refrigerant conveying device, and a plurality of the outdoor flow valves. Each room located between the refrigerant carrier An outdoor unit pressure detecting means for detecting a refrigerant pressure in the vicinity of an external flow valve, an operating outdoor unit determining means for determining which outdoor unit is operating based on an output signal of the operating outdoor unit detecting means, and the transfer device. Refrigerant amount determination means for determining whether the refrigerant circulation amount is insufficient based on the output signals of the pressure detection means and the outdoor unit pressure detection means, based on the output signals of the operating outdoor unit determination means and the refrigerant amount determination means A multi-room cooling and heating device having a drive means for causing a stopped outdoor unit to start a cooling operation. 2. A heat source side refrigerant cycle formed by annularly connecting a compressor, a heat source side heat exchanger, a cooling expansion valve, a heating expansion valve and a first auxiliary heat exchanger, and the first auxiliary heat exchanger. A plurality of outdoor units having a second auxiliary heat exchanger integrally formed with the second auxiliary heat exchanger, and an outdoor flow valve provided in series with the second auxiliary heat exchanger; and a plurality of outdoor units provided in each of the outdoor units. Detecting that the second auxiliary heat exchanger, the outdoor flow valve, a plurality of usage-side heat exchangers, and a usage-side refrigerant cycle in which the refrigerant transfer device is connected in an annular shape, and a plurality of the outdoor units are in operation An operating outdoor unit detecting means, a conveying device pressure detecting means for detecting a refrigerant pressure in the vicinity of the refrigerant conveying device, which is located between the plurality of outdoor flow valves and the refrigerant conveying device, and a plurality of the outdoor flow valves. Located between the refrigerant transfer devices Conveyor temperature detecting means for detecting the temperature of the refrigerant in the vicinity of the refrigerant conveying device, operating outdoor unit determining means for determining which outdoor unit is operating based on the output signal of the operating outdoor unit detecting means, and the conveying device Supercooling degree calculating means for calculating the refrigerant supercooling degree based on the output signals of the pressure detecting means and the conveying device temperature detecting means,
Based on the output signal of the supercooling degree calculation means, a refrigerant amount determination means for determining whether or not the refrigerant circulation amount is insufficient, and for the stop outdoor unit based on the output signals of the operation outdoor unit determination means and the refrigerant amount determination means A multi-room cooling and heating device equipped with a drive means for starting a cooling operation.