JPH0351672A - Air conditioner - Google Patents

Abstract

PURPOSE:To improve a reliability of an operation of an air conditioner by a method wherein a heating exchanging part for performing a heat exchanging operation between a connection pipe between each of indoor devices and the second branch part and a bypassing pipe between the third flow rate control device and a check valve is provided. CONSTITUTION:The first branch part 10 provided with a three-way changingover valve 8 for connecting one of indoor devices B to D to either the first or second connection pipes 6 and 7 in such a way as it may be changed over and the second branch part 11 for connecting the other of the indoor devices B to D to the second connection pipe 7 through the first flow rate control device 9 are connected through the second flow rate control device 15. A bypassing pipe 14 is provided, wherein one end of it is connected to the second branch part 11 and the other end of it is connected to the first and second connection pipes 6 and 7 through check valves 17 and 18 for allowing a flowing of refrigerant only to the third flow rate control device 15, the first and second connection pipes 6 and 7. Heat exchangers 16b to 16d for performing a heat exchanging operation between the connection pipes 7b to 7d between each of the indoor devices B to D and the second branch part 11 and the bypassing pipe 14 between the third flow rate control device 15 and the check valves 17, 18 are provided.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a multi-room type and one-pump type air conditioner in which a plurality of indoor units are connected to one heat source unit, and in particular, The present invention relates to an air conditioner that can selectively perform heating and cooling for each indoor unit, and can simultaneously perform cooling with one indoor unit and heating with the other indoor unit.

[Conventional technology]

Conventionally, heat pump air conditioners have been common in which multiple indoor units are connected to one heat source unit using two pipes, a gas pipe and a liquid pipe, and each indoor unit performs heating and cooling operation. [Problems to be Solved by the Invention] Since the conventional multi-room heat pump type air conditioner is configured as described above, all the indoor units are configured to perform air conditioning. Since it operates only for heating or cooling, there is a problem that heating is performed in places that require cooling, or conversely, cooling is performed in places that require heating.

In particular, when installed in a large building, the air conditioning load is significantly different between the interior section and a portion of the verimeter, or between a general office and a computer room or other open-aired room, which poses a particular problem.

This invention was made in order to solve the above-mentioned problems. Multiple indoor units are connected to one heat source unit, and each indoor unit can selectively and unidirectionally perform heating and cooling. One indoor unit can perform cooling and the other indoor unit can perform heating at the same time, and when installed in a large-scale building, it is possible to open the interior part and part of the Verimeter, general office space, computer room, etc. An object of the present invention is to obtain a multi-room heat pump type air conditioner that can handle each room even if the air conditioning loads differ significantly in each room. One heat source device consisting of a flow valve, a heat exchanger on the heat source side, an accumulator, etc., and a plurality of indoor units consisting of an indoor heat exchanger, a first flow rate control device, etc.
In those connected via the first and second connecting pipes,
a first branching section equipped with a valve device that connects one of the plurality of indoor units to the first connection pipe or the second connection pipe in a switchable manner; and the other of the plurality of indoor units; The above-mentioned second flow rate control device is connected to the indoor unit.
A second branch section connected to the connecting pipe R is connected via a second flow rate control device, and one end is connected to the second branch section and the other end is connected to a third flow rate control device R. and the first above
and a bypass pipe connected to the first and second connecting pipes via a check valve that allows flow only to the second connecting pipe side, and connecting each of the indoor units to the second branch part. The present invention is characterized in that a heat exchange section is provided for exchanging heat between the connecting pipe and the bypass pipe between the third flow rate control device and the check valve.

[Effect]

In this invention, when heating is the main component in simultaneous cooling and heating operation, high-pressure gas refrigerant is introduced from the first connecting pipe and the first branch into each indoor unit to be heated, and then the refrigerant is A part of the air flows from the second branch into the indoor unit to be cooled, and then flows from the first branch into the second connection pipe. Meanwhile, the remaining refrigerant is
The refrigerant flows into the gas-liquid separation device through the flow rate control device, merges with the refrigerant that has passed through the cooling indoor unit, and flows into the second connection pipe,
Return to the heat source device 0 Furthermore, a part of the refrigerant is circulated from the second branch section through the bypass piping, heat exchange is performed in the heat exchange section, the refrigerant is cooled, and the room that is being cooled is sufficiently subcooled. flow into the machine.

In addition, in the case of mainly cooling, high-pressure gas is exchanged with an arbitrary amount of heat using a heat source device, and the gaseous refrigerant is introduced into a two-phase state from the second connecting pipe through the first branch to the indoor unit that is to be heated. It performs heating and flows into the second branch. On the other hand, the remaining liquid refrigerant passes through the second flow rate control device, joins with the refrigerant that has passed through the indoor unit that is attempting to heat at the second branch, and flows into each indoor unit that is attempting to cool. After that, the heat source is guided from the first branch through the first connection pipe to the heat source machine and returns to the compressor. Furthermore, in the process of flowing a part of the refrigerant from the second branch part to the first connection pipe via the bypass pipe, heat exchange is performed in the heat exchange part, and the refrigerant is heated before flowing into the second branch part. The refrigerant is cooled, and the refrigerant that flows out from the second branch to the indoor unit to be cooled is cooled, sufficiently subcooled, and flows into the indoor unit to be cooled.

Furthermore, in the case of only heating operation, the refrigerant is introduced from the heat source device through the first connecting pipe and the first branch to each indoor unit, heated, and then passed from the second branch to the second connecting pipe to the heat source. Return to the machine.

In the case of only cooling operation, the refrigerant is introduced into each indoor unit through the heat source equipment, the second connection pipe, and the second branch, cooled, and then passed from the first branch to the first connection pipe. Return to the heat source machine.

Further, in the process of flowing a part of the refrigerant from the second branch part to the first connection pipe via the bypass pipe, heat exchange is performed in the heat exchange part, and before flowing into the second branch part, The refrigerant is cooled, and the refrigerant that flows out from the second branch to the indoor unit to be cooled is further cooled, sufficiently subcooled, and flows into the indoor unit to be cooled.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 is an overall configuration diagram centered on the refrigerant system of an air conditioner according to a first embodiment of the present invention. Also, Figures 2 to 4
The figure shows the operating state during cooling/heating operation in the embodiment shown in Fig. 1, Fig. 2 shows the operating state of cooling or heating only, and Figs. 3 and 4 show the operation of simultaneous cooling/heating operation. Figure 3 is an operating state diagram showing heating-dominant operation (when the heating operating capacity is greater than cooling operating capacity), and Figure 4 is an operating state diagram showing cooling-dominant operation (when cooling operating capacity is greater than heating operating capacity). . FIG. 5 is an overall configuration diagram centered on the refrigerant system of an air conditioner according to another embodiment of the present invention.

In this embodiment, a case will be described in which three indoor units are connected to one heat source device, but the same applies to a case in which two or more indoor units are connected.

In Figure 1, (A) is a heat source machine, (B) e (0)
#(D) are indoor units connected in parallel to each other, each having the same configuration, as will be described later. (K) is a repeater that incorporates a first branching section, a second flow rate control device, a second branching section, a gas-liquid separation device, and a heat exchange section, as will be described later.

(1) is a compressor, (2) is a four-way valve that switches the refrigerant flow direction of the heat source machine, (3) is a heat exchanger on the heat source machine side, (4) is an accumulator, and the above equipment (1) to (3) and is connected to constitute a heat source unit. (5) is the three indoor heat exchangers, (6) is the four-way valve (2) of the heat source equipment (mu) and the repeater (1c).
), (ab), (60)
, (6a) are indoor units (B) and (0), respectively.
, (D) connects the indoor heat exchanger (5) and the repeater (IC), and the first connection pipe on the indoor unit side corresponding to the first connection pipe (6), (7) is the heat source equipment A second connection pipe connecting the heat source machine side heat exchanger (3) of (A) and the relay machine (E), (
7b), (70) + (711) are the indoor heat exchangers (5) of the indoor units (B), (0), and (D), respectively.
) and the repeater (]e) and the second connection pipe on the indoor unit side corresponding to the second connection pipe (7), (8) is the first connection pipe on the indoor unit side (6b), ( ae), (6(1
) and the first connection pipe (6) or the second connection pipe (
A three-way switching valve (9) is connected in close proximity to the indoor heat exchanger (5) and is connected to the indoor heat exchanger (5) to generate a superheat amount when cooling the outlet side of the indoor heat exchanger (5). During heating, the first flow rate control device is controlled by the sub-cooling amount, and the second connection pipe (7b) on the indoor unit side is connected. ('7G)
IC'76>. αG is the first on the indoor unit side
Connection piping (61:+) # (60) l (6d)
and the first connection pipe (6) or the second connection pipe (7)
) with the exception of the second connecting pipe (+71) on the indoor unit side.
)) y (ツC)p (7d) and the second connection pipe (7
) so υ, 0 is the second connection arrangement F (7
), the gas layer part is connected to No. 10 (8a) of the three-way switching valve (8), and the liquid layer part is connected to the second branch part (■). . The opening is a second flow rate control device that can be opened and closed and is connected between the gas-liquid separation device (6) and the second branch 0, and α4 is the connection between the second branch 0 and the first connecting pipe (6). ) and the bypass pipe connecting the second connection pipe (7), (to) a third flow rate control device provided in the middle of the bypass pipe (2), (16b) (16a
) (164) are respectively provided downstream of the third flow rate control device provided in the middle of the bypass pipe α4, and are the second connection pipes () b) t on the side of each indoor unit of the second branch part 0.
(10) Each heat exchange part performs heat exchange between t ()d), α force is rt Ihas distribution 9 (14
O heat exchange part (16b) (160) (first check valve provided between 16 (1) and the first connection pipe (6), (to) heat exchange part of bypass pipe α4 ω and the above first
The first check valve αη provided between the connecting pipe (7) and the connecting pipe (7)
The first and second check valves (b) and (to) are both connected to the heat exchange section (16b) (16o).
(16(1) side to first and second connection pipes (6) (
7) Allow refrigerant flow only to the side.

An embodiment of the present invention configured as described above will be described. First, a case where only cooling operation is performed will be described using FIG. 2.

That is, as shown by the solid line arrow in the figure, the high-temperature, high-pressure refrigerant gas discharged from the compressor (1) passes through the four-way valve (2),
After being condensed and liquefied by heat exchange in the heat exchanger (3) on the heat source side, it passes through the second connection pipe (7), the gas-liquid separator 4, the second flow rate control device (to), and then the Pass through the second connecting pipe ()b), ()'L(va) on the indoor unit side of branch part 01 of 2, and connect each indoor unit (B) e (0)? (D). And each indoor unit (B) t (0) # (I)
) The refrigerant flowing into the first flow rate control device (
9) The pressure is reduced to low pressure, and in the indoor heat exchanger (5), it exchanges heat with indoor air, evaporates and becomes gas, and cools the room. Then, this gaseous refrigerant is transferred to the first connection pipe (6b) # (6G) # (6(1
), three-way switching valve (8), first branch part ao1 first connection pipe (6), four-way valve of heat source equipment (2), Akiemator (
4) to form a circulation cycle in which air is sucked into the compressor (1) to perform cooling operation. At this time, the three-way switching valve (8)
The 10th (8 &) is a closed circuit, the 20th (8b) and the 30th (
8o) is open circuited.

Also, during this cycle, a part of the refrigerant that has passed through the second flow control device 0 enters the bypass pipe α4, is reduced to a low pressure by the third flow control device (2), and is transferred to the heat exchange section (16b).
(1aa) At (z6a), the refrigerant evaporated through heat exchange with the second connection pipe <-tb>, <C), and ()d) on the side of each indoor unit of the second branch part 0, respectively. passes through the first check valve α force, enters the first connection pipe (6), passes through the four-way valve (2) of the heat source machine, the accumulator (4), and then enters the compressor (1).
) is inhaled. At this time, since the first connecting pipe (6) is at low pressure and the second connecting pipe (7) is at high pressure, the flow inevitably flows through the α force side of the first check valve. On the other hand, the heat exchange part (16b) (1
The refrigerant that has been cooled by heat exchange in 6c) (1aa) and sufficiently subcooled passes through the second connecting pipe (7b) (7G) (7(L) on the indoor unit side to the indoor unit (7(L)) that is about to be cooled. B) (0) Flows into (D).

Next, the case of only heating operation will be described using FIG. 2. In other words, as shown by the dotted arrow in the same figure, the compressed al
The high-temperature, high-pressure refrigerant gas discharged from (1) passes through the four-way valve (2), the first connecting pipe (6), and the first branch part α.
01 Three-way switching valve (8), first connection pipe on the indoor unit side (6
b) t (ao) t (611), flows into each indoor unit (B) (0) l (1)), exchanges heat with indoor air, condenses and liquefies, and heats the room. Then, this liquid refrigerant is transferred to the first flow rate control device (9), which is controlled by the subcooling amount at the outlet of each indoor heat exchanger (5).
), the second connection pipe (7'b) on the indoor unit side, (7
゜).

() d) flows into the second branch I, merges, and then flows into the second flow control device! ! 2 (13), where the pressure is reduced to a low-pressure two-phase state by either the first flow control device (9) or the second flow control device (2).Then, the refrigerant reduced to a low pressure The refrigerant flows into the heat source unit side heat exchanger (3) of the heat source unit (λ) through the gas-liquid separator @ and the second connection pipe (7), exchanges heat, evaporates, and becomes a gas. A circulation cycle is configured in which air is sucked into the compressor (1) via the four-way valve (2) of the heat source device and the accumulator (4), and heating operation is performed.At this time, the three-way switching valve (8) It is opened and closed in the same way as when driving only.

A case in which heating is the main component in simultaneous cooling and heating operation will be described with reference to FIG.

That is, as shown by the dotted arrow in the figure, the high temperature and high pressure refrigerant gas discharged from the compressor (1) is transferred to the first connection pipe (6).
) to the relay (phantom), and the first branch 0
01 Mi-way switching valve 18), the first connection pipe on the indoor unit side (6
b) * Passes in the order of (6c), flows into each indoor unit (B) and (0) to be heated, and enters the indoor heat exchanger (5).
), it exchanges heat with the indoor air and is condensed and liquefied, heating the room. This condensed and liquefied refrigerant is controlled by the subcooling amount at the outlet of each indoor heat exchanger (B) (0), passes through the first flow rate control device (9) that is almost fully open, and is slightly depressurized and then transferred to the second flow rate control device (9). It flows into the branch αυ.

A part of this refrigerant passes through the second connecting pipe ('i'd) on the indoor unit side to the indoor unit (D) K
After entering the first flow rate control device (9) controlled by the amount of superheat at the outlet of the indoor heat exchanger (D) and being depressurized, it enters the indoor heat exchanger (5) for heat exchange. It evaporates, becomes a gas, cools the room, and activates the three-way switching valve (8).
into the gas-liquid separator@.

On the other hand, the other refrigerant flows into the gas-liquid separation device @ through the second flow rate control device (to) controlled by the high and low pressure values that can be opened and closed in the second branch part o1 and the second connection pipe, It joins with the refrigerant that has passed through the indoor unit (1) to be cooled and flows into the second
It flows into the connecting pipe (7) of the heat source device (A), flows into the heat source device side heat exchanger (3) of the heat source device (A), exchanges heat, and evaporates into a gas state. Then, the refrigerant forms a circulation cycle in which the refrigerant is sucked into the compressor (1) through the four-way valve (2) of the heat source device and the accumulator (4), thereby performing heating-dominant operation. At this time, the 10th (8&) of the three-way switching valve (8) connected to the indoor unit (B) (0) is closed, the 20th (8b) and the 30th (8o)
) is open, the 20th (8b) of the indoor unit (D) is closed, and the 10th (8a) and 30th (8c) are open.

Also, during this cycle, some of the liquid refrigerant enters the bypass pipe α4 from the second connection pipe () b) t (7o) t () d) on each indoor unit side, and enters the bypass pipe α4 on the third flow rate control device side. The pressure is reduced to low pressure and the heat exchange section (z6b) (16o) (1
In step 6 (1), the refrigerant that has undergone heat exchange and evaporated passes through the second check valve (to), enters the second connection pipe (7), and enters the heat source unit side of the heat source unit (A). It flows into the heat exchanger (3), exchanges heat, and evaporates into a gas state. The refrigerant is then sucked into the compressor (1) through the four-way valve (2) of the heat source device and the accumulator (4). At this time, the first connection pipe (6)
However, since the connecting pipe (7) of the high pressure cylinder 2 is low pressure, the second
Flows through the check valve (to) side of the valve. On the other hand, the heat exchange section (16'
b) The refrigerant that has been heat exchanged, cooled and subcooled in (16a) and (161) flows into the second branch section 0, and further flows from the second branch section 0 to the heat exchange section (16 (1)). The air is cooled through heat exchange, is sufficiently subcooled, and flows into the indoor unit (D) that is attempting to cool the air.

A case in which cooling is the main component in simultaneous heating and cooling operation will be described with reference to FIG. 4.

That is, as shown by the solid arrow in the figure, the high-temperature, high-pressure refrigerant gas discharged from the compressor (1) is transferred to several heat sources and a heat exchanger (
In 3), exchange any amount of heat to create a two-phase high-temperature, high-pressure state.#)
It is sent to the gas-liquid separator (A) of the repeater (E) through the second connection pipe (7). Here, the refrigerant is separated into a gaseous refrigerant and a liquid refrigerant, and the separated gaseous refrigerant is transferred to the first branch αG, the three-way switching valve (8), and the first connection pipe (6d) on the indoor unit side in this order. Indoor unit trying to heat the street (D)
It flows into the indoor heat exchanger (D), exchanges heat with indoor air, condenses and liquefies, and heats the room. Furthermore, it is controlled by the subcooling amount at the outlet of the indoor heat exchanger (1), and passes through the first flow rate control device (9), which is in an almost fully open state, and is slightly depressurized before flowing into the second branch section. On the other hand, the remaining liquid refrigerant is
Indoor unit (1) flowing into the second branch U through the second flow rate control device α9 controlled by the openable and closable high and low pressure values of the second connecting pipe (11) and heating the indoor unit (1)
) and joins with the refrigerant that has passed through it. And the second branch part 0,
It passes through the second connection pipes () 13) (7G) on the indoor unit side in this order and flows into each indoor unit (II) l(0).

Then, the refrigerant flowing into each indoor unit CB)IcO) is controlled by the first flow rate control device [9] controlled by the amount of super and -t at the outlet of the indoor heat exchanger (B)t(G). It is reduced to a low pressure, exchanges heat with indoor air, evaporates, and becomes gas, cooling the room. Furthermore, this refrigerant in a gas state is transferred to the first connecting pipe (6b) (6a) on the indoor unit side, the three-way switching valve (8), the first branch no., the first connecting pipe (6), and the heat source. This constitutes a circulation cycle in which air is sucked into the compressor (1) through the four-way valve (2) and accumulator (4) of the machine, and performs mainly cooling/cooling operation. At this time, the 10th (8&) of the three-way switching valve (8) connected to the indoor unit (B) (0) (ri)
- No. 30 (80) are opened and closed in the same way as in the heating-based operation. Also, during this cycle, some of the liquid refrigerant is transferred to the second connection pipe ('7b) on each indoor unit side, (〒O) l (7
6) enters the bypass pipe (2), which is reduced to a low pressure by the third flow control device (toward) and then transferred to the heat exchange section (1).
ab) (16G) At (16a), the refrigerant that has undergone heat exchange and evaporated passes through the first check valve actuator and enters the first connecting pipe (6). ) and is sucked into the compressor (1) via the accumulator (4). At this time,
Since the first connecting pipe (6) has a low pressure and the second connecting pipe (7) has a high pressure, the first check valve α titer inevitably flows therethrough. On the other hand, the refrigerant that has been heat exchanged, cooled, and subcooled in the heat exchange part (16(1)) flows into the second branch part 0, and from the second branch part 0υ to the heat exchange part (16b) (16o
), the indoor unit (B) (Q
).

In the above embodiment, a three-way switching valve (8) is provided to connect the first connection pipe (61) on the indoor unit side (6Q) p (
6a> and the first connection pipe (6) or the second connection pipe (7) in a switchable manner, as shown in FIG. Even if an on-off valve such as the above is provided and connected in a switchable manner as described above, the same effect can be obtained.

[Effects of the Invention] As explained above, the air conditioner of the present invention includes one heat source machine, a plurality of indoor units and compressors, a four-way valve, a heat exchanger on the heat source machine side, an accumulator, etc. In a system in which one heat source device consisting of a heat source device and a plurality of indoor units consisting of an indoor heat exchanger, a first flow rate control device, etc. are connected via first and second connection pipes, the plurality of indoor units A first branching part equipped with a valve device that connects one of the indoor units to the first connection pipe or the second connection pipe in a switchable manner, and the other of the plurality of indoor units are connected to the first connection pipe or the second connection pipe. A second branch section connected to the second connection pipe via a first flow control device connected to the machine is connected via a second flow control device, and one end is connected to the second connection pipe. connected to the branch part, and the other end is connected to the first and second connecting pipes via a check valve that allows flow only to the third flow rate control device and the first and second connecting pipes. It is equipped with bypass piping that connects each of the above indoor units and the second
A heat exchange section is provided for exchanging heat between a connecting pipe connected to the branch part of and a bypass pipe between the third flow rate control device and the check valve.

Therefore, cooling and heating can be performed selectively, with one indoor unit performing cooling and the other indoor unit heating at the same time.Furthermore, the liquid refrigerant can be sufficiently subcooled according to each connection pipe distributed to the indoor units. Therefore, subcooling can be secured in front of the first flow rate control device connected to each indoor unit that performs cooling operation, and reliability is improved.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram centered on the refrigerant system of an air conditioner according to a first embodiment of the present invention. Fig. 2 is a diagram showing the operating state of cooling or heating only in the embodiment shown in Fig. 1, and Fig. 3 is a diagram showing the operating state of the embodiment shown in Fig. 1 mainly in heating (heating operation capacity is smaller than cooling operation capacity). operation state diagram for (large case),
FIG. 4 is an operating state diagram showing the main cooling operation (when the cooling operation capacity is larger than the heating operation capacity) of the embodiment shown in FIG. 1, and FIG. FIG. 2 is an overall configuration diagram centered on the refrigerant system of the harmonizer. In the figure, (A) is the heat source machine, (B) I (0) #
(D) is an indoor unit, (E) is a repeater, (1) is a compressor,
(2) is the four-way valve of the heat source machine, (3) is the heat exchanger on the heat source machine side,
(4) is an accumulator, (5) is an indoor heat exchanger, (
6) is the first connection pipe, (6b) #(60) e (
6") is the first connection pipe on the indoor unit side, (7) is the second connection pipe, ()b), (gC), (gd) is the second connection pipe on the indoor unit side, ( 8) is a three-way switching valve, c9) is the first flow rate control device, αG is the first branch, wholesale is the second branch,
@ is the gas-liquid separation device, @ is the second flow rate control device, α4 is the bypass piping, (2) is the third flow rate control device, (16b)
(160) (164) is the heat exchange part, Q7)m is the first
and a second check valve. In addition, the same symbols in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] Compressor, 4-way valve, heat source machine side exchanger, accumulator, etc.
A heat source device consisting of one heat source device and a plurality of indoor units consisting of an indoor heat exchanger, a first flow rate control device, etc. are connected via first and second connection piping. A first branching section includes a valve device that connects one of the indoor units to the first connection pipe or the second connection pipe in a switchable manner, and the other of the plurality of indoor units is connected to the indoor unit. A second branch section connected to the second connecting pipe via a first flow control device connected to and the other end is connected to the first and second connecting pipes via a check valve that allows flow only to the third flow rate control device and the first and second connecting pipes. A heat exchange section that includes bypass piping and performs heat exchange between the connection piping between each of the indoor units and the second branch section and the bypass piping between the third flow rate control device and the check valve. An air conditioner characterized by being provided with.