JPH0545017A - Multi-chamber type cooling or heating device - Google Patents

Abstract

PURPOSE:To improve a high lifting performance of a system and reduce an amount of enclosed refrigerant in a multi-chamber type cooling or heating device in which a refrigerant cycle at a heat source side and another refrigerant cycle at a utilizer are separated by a method wherein a proper amount of gaseous refrigerant within a small liquid side connection pipe is mixed with refrigerant under an over-cooled state in which a condensed and liquefied state is attained with a heat exchanger at the utilizer during a heating operation. CONSTITUTION:The first flow rate valve 14a for refrigerant is connected to a heat exchanger 12a of an indoor device b1, and the second flow rate valve 15a is arranged in parallel with the first flow rate valve 14a. Temperature sensing devices 16a and 17a for detecting refrigerant temperatures at an outlet of the indoor device and the outlet of the second flow rate valve 15a are provided. A control device 18a adjusts a degree of opening of the second flow rate valve 15a in response to the detected temperature. Accordingly, since a proper amount of saturated gas in a small liquid branch pipe d1 is mixed in a multi-liquid branch pipe (e1), a resistance caused by a weight of the liquid refrigerant within the multi-liquid side connection pipe (c) and a proper refrigerant circulation can be attained even if a high height difference is found between the refrigerant transporting device 11 and the indoor devices (b1, b2) and further an amount of enclosed gas can be reduced. As for the indoor device (b2) a similar state can be attained.

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 which is divided into a heat source side refrigerant cycle and a use side refrigerant cycle.

[0002]

2. Description of the Related Art Conventionally, a refrigerant cycle of a multi-chamber cooling and heating apparatus separated into a heat source side refrigerant cycle and a use side refrigerant cycle is
As shown in Japanese Patent Laid-Open No. 62-238952, FIG.
Was configured like.

In FIG. 4, 1 is a compressor, 2 is a heat source side four-way valve, 3 is a heat source side heat exchanger, 4 is a cooling decompression device, 5 is a heating decompression device, and 6 is a cooling decompression device 4 during heating. Is a check valve for closing the heating decompression device 5 during cooling, and 8 is a first auxiliary heat exchanger, and these are connected in an annular shape to form a heat source side refrigerant cycle. .. 9 is the second
The auxiliary heat exchanger is integrally formed so as to exchange heat with the first auxiliary heat exchanger 8.

Reference numeral 10 is a refrigerant amount adjusting tank for adjusting the amount of refrigerant during cooling and during heating. Reference numeral 11 is a refrigerant transfer device. The components of the heat source side refrigerant cycle, the refrigerant amount adjustment tank 10 and the refrigerant transfer device 11 are housed in the heat source side unit a. 12a and 12b are heat exchangers on the use side, which are housed in the indoor units b1 and b2, respectively, and are connected to the multi-liquid side connecting pipe C, the low-liquid side connecting pipe C ′, the low-liquid side branch pipes d1 and d2, and the multi-liquid side branch pipe e1, It is connected to the heat source side unit a at e2.

Numeral 13 is a four-way valve on the use side, which is an indoor unit b
The flow direction of the refrigerant to 1 and b2 is changed by cooling and heating. 1
4a and 14b are flow valves, which are utilization side heat exchangers 12a and 12
The refrigerant flow rate to b is adjusted.

Second auxiliary heat exchanger 9, refrigerant amount adjusting tank 1
0, refrigerant transfer device 11, flow rate valves 14a, 14b, use side heat exchangers 12a, 12b, use side four-way valve 13, multiple liquid side connecting pipe C, small liquid side connecting pipe C ', small liquid side branch pipes d1, d
2. The multiple liquid side branch pipes e1 and e2 are connected in a ring shape to form a use side refrigerant cycle.

The operation of the cooling and heating apparatus configured as described above will be described. During the cooling operation, the refrigerant cycle is indicated by the solid arrow in the figure, and in the heat source side refrigerant cycle, the compressor 1
The high-temperature high-pressure gas from 4 passes through the four-way valve 2, radiates heat in the heat-source-side heat exchanger 3 to be condensed and liquefied, passes through the check valve 6 and is decompressed by the cooling expansion valve 4, and then by the first auxiliary heat exchanger 8. It evaporates and passes through the heat source side four-way valve 2 and circulates to the compressor 1.

At this time, the second auxiliary heat exchanger 9 and the first auxiliary heat exchanger 8 of the use side refrigerant cycle exchange heat, the gas refrigerant of the use side refrigerant cycle is cooled and liquefied, and the refrigerant amount adjusting tank 10, It is sent to the refrigerant carrier device 11 through the user-side four-way valve 13, and by this refrigerant carrier device 11, the user-side four-way valve 1
3, the use side heat exchanger 12a through the multi-liquid side connecting pipe C,
It is sent to 12b, cooled, endothermicly evaporated, gasified, and circulated to the second auxiliary heat exchanger 9 through the small liquid side connection pipe C '.

At this time, the indoor unit b of the user side cycle
In 1 and b2, the flow rate of the refrigerant is adjusted by adjusting the flow rate valves 14a and 14b, respectively, while monitoring the room temperature, for example. That is, when the indoor temperature becomes low, the opening of the flow valve is made small so that the refrigerant does not easily flow. On the contrary, when the indoor temperature does not decrease, the opening of the flow valve is made large and a large amount of the refrigerant flows. Is adjusted.

On the other hand, during the heating operation, the refrigerant cycle is indicated by the broken line arrow, and in the heat source side refrigerant cycle, the high-temperature high-pressure refrigerant from the compressor 1 passes from the heat source side four-way valve 2 to the first side.
It is sent to the auxiliary heat exchanger 8, radiates heat to be condensed and liquefied, decompressed from the check valve 7 by the heating decompression device 5, absorbed and evaporated by the heat source side heat exchanger 3, and compressed through the heat source side four-way valve 2. Circulate to machine 1.

At this time, the second auxiliary heat exchanger 9 and the first auxiliary heat exchanger 8 of the utilization side refrigerant cycle exchange heat, the liquid refrigerant in the utilization side refrigerant cycle is heated and gasified, and the small amount liquid side connecting pipe It is sent to the use side heat exchangers 12a and 12b through C'and the small liquid side branch pipes d1 and d2, and is heated and radiated to liquefy the heat, and passes through the flow valves 14a and 14b, and the multiple liquid side branch pipes e1 and e2 and the multiple liquids. It is sent to the refrigerant transfer device 11 through the side connection pipe C and the use side four-way valve 13, and circulates from the refrigerant amount adjustment tank 10 to the second auxiliary heat exchanger 9.

At this time, the indoor unit b of the use side cycle
In 1 and b2, the flow rate of the refrigerant is adjusted by adjusting the flow rate valves 14a and 14b, respectively, while monitoring the room temperature, for example. That is, when the indoor temperature is high, the opening of the flow valve is reduced so that the refrigerant does not easily flow. On the contrary, when the indoor temperature is low, the opening of the flow valve is increased so that the refrigerant flows more. I am adjusting.

[0013]

However, in the above configuration, in order to adjust the room temperature during the heating operation,
When adjusting in the direction of capacity control to reduce the flow rate of the refrigerant, the condensation capacity of the heat exchanger on the use side increases, so the refrigerant is in a supercooled state, that is, a complete liquid state and exits the indoor unit. It will be.

For this reason, the multi-liquid side branch pipe and the multi-liquid side connecting pipe are also filled with the refrigerant in the supercooled liquid state, and in order to properly circulate the refrigerant, the amount of the enclosed refrigerant is very large. Will be needed.

Further, when the difference in height between the refrigerant transporting device and the lowermost indoor unit exceeds a certain value, resistance due to the weight of the refrigerant in the supercooled liquid state in the multi-liquid side branch pipe or the multi-liquid side connection pipe is caused. However, there is a problem that proper refrigerant circulation is hindered and the system becomes inoperable.

In view of the above problems, the present invention aims to improve the high head performance of the system and reduce the amount of the enclosed refrigerant.

[0017]

In order to solve the above problems, the multi-room cooling and heating apparatus of the present invention adjusts the flow rate of the refrigerant which is connected in series with the use side heat exchanger and flows to the use side heat exchanger. The indoor unit has a first flow valve, the use-side heat exchanger connected in series, and a second flow valve arranged in parallel with the first flow valve, and the refrigerant at the outlet of the indoor unit during heating. A first temperature detecting device for detecting a temperature, a second temperature detecting device for detecting a refrigerant temperature at the outlet of the second flow valve during heating, and a refrigerant temperature detected by the first and second temperature detecting devices for the first temperature detecting device. A control device for controlling the two flow valves is provided.

[0018]

According to the multi-chamber cooling and heating apparatus of the present invention, the second flow valve arranged in parallel with the heat exchanger on the use side is controlled during the heating operation by the above-mentioned structure, and the heat exchanger on the use side condenses and liquefies the fluid. An appropriate amount of the gas refrigerant in the low-liquid-side connection pipe is mixed with the liquid refrigerant in the cooled state.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multi-room air conditioner according to an embodiment of the present invention will be described below with reference to the refrigerant cycle diagram of FIG. 1, the flowchart of FIG. 2 and the graph of FIG.

FIG. 1 shows a refrigerant cycle of a multi-room cooling and heating apparatus according to an embodiment of the present invention, which includes 15a and 15b.
Are the use side heat exchangers 12a, 1 connected in series, respectively.
2b and second flow valves 14a and 14b, which are arranged in parallel with each other, and 16a and 16b are the second flow valve 1
5a, 15b and the first flow valves 14a, 14b, and the multi-liquid side branch pipes e1, e2, respectively.
It is a 1st temperature detection apparatus which detects each outlet temperature of indoor units b1 and b2.

Reference numerals 17a and 17b denote second flow rate valves 15a and 1b.
5b, the second flow valves 15a and 15b, and the first flow valve 14
a, 14b is a second temperature detecting device for detecting the refrigerant temperature between the merging portion, and 18a, 18b are the second and the second flow rates depending on the refrigerant temperatures detected by the first and second temperature detecting devices 16a, 16b, 17a, 17b. It is a control device that adjusts the opening degrees of the valves 15a and 15b.

The second flow valve is the control device 18a, 18
The opening degree can be adjusted linearly by the pulse generated from b, and it has a characteristic that it opens when a positive pulse is generated and closes when a negative pulse is generated. The saturated gas refrigerant in the small liquid side branch pipes d1 and d2 is The multi-liquid side branch pipes e1 and e2 are always in a slightly opened state so as to be bypassed little by little.

The other structure is the same as that of the conventional example, and therefore the same reference numerals are used here and the description thereof is omitted.

The operation of this refrigerant cycle is also the same as that of the conventional example, and detailed description thereof will be omitted. However, the second flow rate valves 15a and 15b and the control device 18 different from the conventional example are omitted.
The description of a and 18b will be given below.

In FIG. 2, in step 1, the indoor units b1 and b detected by the first temperature detecting devices 16a and 16b are detected.
No. 2 outlet refrigerant temperatures T1a, T1b and the second flow rate valve 15 detected by the second temperature detecting devices 17a, 17b.
From the respective outlet refrigerant temperatures T2a and T2b of a and 15b, temperature differences Tta and Ttb (Tta = T1a−T2a,
Ttb = T1b-T2b) is calculated.

Now, assuming that the heating load of the room in which the indoor unit b2 is installed is reduced and the indoor temperature is increased, the opening of the first flow valve 14b is reduced to perform capacity control. Since the flow rate of the refrigerant flowing to the usage-side heat exchanger 12b decreases, the refrigerant flowing through the usage-side heat exchanger 12b sufficiently exchanges heat and becomes in a supercooled state, for example, in the indoor unit b2 detected by the first temperature detection device 16b. The outlet refrigerant temperature T1b is assumed to be 30 ° C.

On the other hand, since the second flow valve 15b is always kept in a slightly opened state, the saturated gas refrigerant in the small liquid side branch pipe d2 bypasses the multi liquid side branch pipe e2 without heat exchange.
The refrigerant at the outlet of the flow valve 15b is in a saturated gas state, and the second flow valve 15 detected by, for example, the second temperature detection device 17b.
The outlet refrigerant temperature T2b of b is 40 ° C.

On the other hand, in the room in which the indoor unit b1 is installed, there is no change in the heating load. Therefore, the outlet refrigerant temperature T1a of the indoor unit b1 detected by the first temperature detection device 16a and the second temperature detection device 17a. It is assumed that the outlet refrigerant temperature T2a of the second flow rate valve 15a detected in step 2 is both 40 ° C.

In step 1 of the control device 18a, the difference Tta between the refrigerant temperatures detected by the first and second temperature detection devices 16a and 17a is 0K, and in step 1 of the control device 18b, the first and second temperature The difference Ttb between the refrigerant temperatures detected by the detection devices 16b and 17b is 10K.

Next, at step 2, the target predetermined value To (for example, -1K) and the temperature difference Tta, Ttb between the previous calculation results.
Difference ΔTa, ΔTb (ΔTa = To−Tta, ΔTb
= To-Ttb) is calculated.

Since Tta = 0K and Ttb = 10K, ΔTa = (-1) -0 and ΔTb = (-1) -1.
0, that is, ΔTa = −1K and ΔTb = −11K.

In step 3, the above calculation result ΔTa,
Based on ΔTb, the calculation results ΔTa and ΔTb in step 2 shown in the graph of FIG. 3 and the determined pulse numbers P1 and P
From the relationship of 2, the number of pulses for operating the second flow valves 15a and 15b is determined.

The relationship between the calculation result ΔT in step 2 and the number of pulses P is a primary relationship because the larger the absolute value of the calculation result in step 2, the pulse determined in step 3. It shows that the number will increase, and now it is △ Ta.
= -1K and ΔTb = -11K, the second from FIG.
The operation pulse number P of the flow valve 15a becomes 0 pulse,
The operation pulse number P of the flow valve 15b is 50 pulses.

In step 4, the second flow valves 15a and 15b are operated by the number of pulses determined in step 3.

As described above, according to the present embodiment, when the indoor units b1 and b2 perform capacity control during the heating operation and the first flow valves 14a and 14b are adjusted so as to reduce the refrigerant flow rate, the user side The condensing ability of the heat exchangers 12a and 12b becomes large with respect to the reduced refrigerant flow rate, and the state of the refrigerant is the supercooled state, that is, even when the indoor unit becomes a complete liquid state, the first temperature detection is performed. Devices 16a, 1
6b and the refrigerant temperature detected by the second temperature detection devices 17a and 17b, the control devices 18a and 18b operate the second flow valves 15a and 15b to connect the multiple liquid side branch pipes e1 and e2 of the indoor units b1 and b2. Since an appropriate amount of the saturated gas in the small liquid side branch pipes d1 and d2 is mixed, the resistance due to the weight of the liquid refrigerant in the multiple liquid side connection pipe C is reduced, and the height difference between the refrigerant transfer device 11 and the indoor units b1 and b2 is large. Even then, proper refrigerant circulation can be realized.

By mixing a gas refrigerant into the supercooled liquid refrigerant in the multi-liquid side branch pipes e1, e2 and the multi-liquid side connecting pipe C, the multi-liquid side branch pipes e1, e2 and the multi-liquid side connecting pipe Since the density of the refrigerant in C can be reduced, the amount of enclosed gas can be reduced.

[0037]

As described above, the multi-room air conditioner of the present invention is connected in series with the use side heat exchanger and is connected in series with the first flow valve for adjusting the flow rate of the refrigerant flowing to the use side heat exchanger. Temperature for detecting the refrigerant temperature at the outlet of the indoor unit at the time of heating, the indoor unit having the use-side heat exchanger connected to the first heat exchanger and the second flow valve arranged in parallel with the first flow valve A detection device, a second temperature detection device that detects the refrigerant temperature at the outlet of the second flow valve during heating, and a control that controls the second flow valve based on the refrigerant temperatures detected by the first and second temperature detection devices. It is equipped with a device and mixes an appropriate amount of the saturated gas of the small liquid side branch pipe into the multi liquid side branch pipe, so the resistance due to the weight of the liquid refrigerant in the multi liquid side connection pipe is reduced, and the refrigerant transfer device and the indoor unit Even if the height difference becomes large, proper refrigerant circulation can be realized. To become.

Further, by mixing the gas refrigerant into the supercooled liquid refrigerant in the multi-liquid side branch pipe or the multi-liquid side connecting pipe, the density of the refrigerant in the multi-liquid side branch pipe or the multi-liquid side connecting pipe can be reduced. Therefore, there is an effect that the amount of enclosed gas can be reduced.

[Brief description of drawings]

FIG. 1 is a refrigeration cycle diagram of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating the operation of the control device according to the embodiment of the present invention.

FIG. 3 is a graph showing the relationship between the temperature difference and the operation pulse amount in the flowchart of FIG. 2 of the present embodiment.

FIG. 4 is a refrigeration cycle diagram of a conventional multi-room air conditioner

[Explanation of symbols]

 12a, 12b Use side heat exchanger 14a, 14b First flow valve 15a, 15b Second flow valve 16a, 16b First temperature detecting device 17a, 17b Second temperature detecting device 18a, 18b Control device b1, b2 Indoor unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiko Marumoto 3-22 Takaidahondori, Higashi-Osaka City, Osaka Prefecture Matsushita Cold Machinery Co., Ltd.

Claims (1)

[Claims] 1. A heat source side refrigerant cycle comprising a compressor, a heat source side four-way valve, a heat source side heat exchanger, a pressure reducing device, and a first auxiliary heat exchanger connected in an annular shape, and the first auxiliary heat exchanger. An outdoor unit having a second auxiliary heat exchanger that is formed into a heat exchanger and exchanges heat, a refrigerant transfer device that is arranged in series with the second auxiliary heat exchanger, a use side heat exchanger, and the use side heat exchange First flow valve connected in series with the heat exchanger to adjust the flow rate of the refrigerant flowing to the use side heat exchanger, and a second flow valve arranged in parallel with the use side heat exchanger and the first flow valve connected in series A plurality of indoor units connected in parallel having a flow valve, the indoor unit, the second auxiliary heat exchanger, and a usage-side refrigerant cycle formed by connecting the refrigerant transfer device in an annular shape; First to detect the refrigerant temperature at the indoor unit outlet
A temperature detecting device, a second temperature detecting device that detects the refrigerant temperature at the outlet of the second flow valve during heating, and a second temperature valve that is controlled by the refrigerant temperatures detected by the first and second temperature detecting devices. A multi-room air conditioner with a control device.