CN115461561A

CN115461561A - Refrigeration cycle device

Info

Publication number: CN115461561A
Application number: CN202080100002.1A
Authority: CN
Inventors: 行德骏哉; 梁池悟
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2022-12-09
Also published as: US20230099489A1; JP7317224B2; JPWO2021220486A1; EP4145028A4; WO2021220486A1; EP4145028A1

Abstract

A refrigeration cycle device (1000) comprises a refrigerant circuit in which a refrigerant circulates, and the refrigerant circuit is provided with a compressor (1), a flow path switching unit (2), an outdoor heat exchanger (3), pressure reduction devices (4A, 4B), a 1 st indoor heat exchanger (5A), a 1 st connecting pipe (10), and a 2 nd connecting pipe (11). The refrigerant circuit further includes a 1 st three-way valve (8A) and a 2 nd three-way valve (9A), the 1 st three-way valve (8A) being disposed downstream of the 1 st indoor heat exchanger in the cooling operation state and upstream of the 1 st indoor heat exchanger in the heating operation state, and the 2 nd three-way valve (9A) being disposed upstream of the 1 st indoor heat exchanger in the cooling operation state and downstream of the 1 st indoor heat exchanger in the heating operation state. The 1 st opening (P1) of each of the 1 st three-way valve and the 2 nd three-way valve is connected to one end or the other end of the 1 st indoor heat exchanger in the refrigerant circuit. A2 nd opening (P2) of each of the 1 st three-way valve and the 2 nd three-way valve is connected to a 1 st connecting pipe. A3 rd opening (P3) of each of the 1 st three-way valve and the 2 nd three-way valve is connected to a 2 nd connecting pipe. The 1 st three-way valve and the 2 nd three-way valve are switched independently of each other to any one of a 1 st state in which a spool (15) is located at a 1 st position, a 2 nd state in which the spool is located at a 2 nd position, and a 3 rd state in which the spool is located at a 3 rd position. In the 1 st state, a 1 st space (S1) which is communicated with the 1 st opening part and the 2 nd opening part and is divided from the 3 rd opening part is arranged in the valve housing (16), in the 2 nd state, a 2 nd space (S2) which is communicated with the 1 st opening part, the 2 nd opening part and the 3 rd opening part is arranged in the valve housing, and in the 3 rd state, a 3 rd space (S3) which is communicated with the 1 st opening part and the 3 rd opening part and is divided from the 2 nd opening part is arranged in the valve housing.

Description

Refrigeration cycle device

Technical Field

The present disclosure relates to a refrigeration cycle apparatus.

Background

Conventionally, a refrigeration cycle apparatus is known which includes an outdoor unit, a relay unit, and a plurality of indoor units, and the outdoor unit and the plurality of indoor units are connected by the relay unit.

Japanese patent application laid-open No. 4-6361 discloses the above-described refrigeration cycle apparatus in which the outdoor unit and the relay are connected by the 1 st refrigerant pipe and the 2 nd refrigerant pipe. The refrigeration cycle device is provided with a 1 st refrigerant flow switching mechanism arranged in an outdoor unit and a 2 nd refrigerant flow switching mechanism arranged in a relay.

The 1 st flow path switching mechanism includes 1 four-way valve and 4 check valves. The 1 st refrigerant flow path mechanism switches between a cooling operation state in which the outdoor heat exchanger functions as a condenser and a heating operation state in which the outdoor heat exchanger functions as an evaporator, and maintains a state in which the pressure of the refrigerant flowing through the 1 st refrigerant pipe is lower than the pressure of the refrigerant flowing through the 2 nd refrigerant pipe, regardless of the switching between the cooling operation state and the heating operation state. The 1 st refrigerant pipe has an inner diameter larger than that of the 2 nd refrigerant pipe. In this way, in the refrigeration cycle apparatus, the increase in pressure loss in the 1 st refrigerant pipe and the 2 nd refrigerant pipe, which occurs as the cooling operation state and the heating operation state are switched, is suppressed, and the decrease in the operating performance is suppressed.

In addition, the 2 nd flow path switching mechanism includes a plurality of flow path switching valves. In the 1 st operation state or the 2 nd operation state, the 2 nd refrigerant flow path mechanism switches between a cooling only operation state or a heating only operation state in which all of the plurality of indoor units function as evaporators or condensers, and a cooling main operation state or a heating main operation state in which a part of the plurality of indoor units function as condensers and another part of the plurality of indoor units function as evaporators.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 4-6361

Disclosure of Invention

Problems to be solved by the invention

In the refrigeration cycle apparatus described above, when the load on the indoor heat exchanger is reduced, it is necessary to reduce the driving frequency of the compressor and reduce the amount of refrigerant circulation in order to prevent a reduction in comfort.

However, in the refrigeration cycle apparatus, when the circulation amount of the refrigerant decreases, the differential pressure before and after the check valve constituting the 1 st flow path switching mechanism decreases, and therefore self-excited vibration occurs.

A main object of the present disclosure is to provide a refrigeration cycle apparatus that suppresses the occurrence of self-excited vibration while preventing a reduction in comfort when a load of an indoor heat exchanger is reduced.

Means for solving the problems

The refrigeration cycle apparatus of the present disclosure includes a refrigerant circuit in which a refrigerant circulates, the refrigerant circuit including a compressor, a flow path switching unit, an outdoor heat exchanger, a pressure reducing device, a 1 st indoor heat exchanger, a 1 st connecting pipe through which a refrigerant flowing into the 1 st indoor heat exchanger flows, and a 2 nd connecting pipe through which a refrigerant flowing out of the 1 st indoor heat exchanger flows. The flow path switching unit switches between a cooling operation state in which the outdoor heat exchanger functions as a condenser and a heating operation state in which the outdoor heat exchanger functions as an evaporator. The refrigerant circuit further includes a 1 st three-way valve and a 2 nd three-way valve, the 1 st three-way valve being disposed downstream of the 1 st indoor heat exchanger in the cooling operation state and upstream of the 1 st indoor heat exchanger in the heating operation state, and the 2 nd three-way valve being disposed upstream of the 1 st indoor heat exchanger in the cooling operation state and downstream of the 1 st indoor heat exchanger in the heating operation state. The 1 st and 2 nd three-way valves include a valve seat including a valve housing (valve chamber) and a 1 st, a 2 nd, and a 3 rd opening connected to the valve housing, and a valve body moving between a 1 st, a 2 nd, and a 3 rd position in the valve housing, respectively. The 1 st opening of each of the 1 st three-way valve and the 2 nd three-way valve is connected to one end or the other end of the 1 st indoor heat exchanger in the refrigerant circuit. The 2 nd opening of each of the 1 st three-way valve and the 2 nd three-way valve is connected to the 1 st connecting pipe. The 1 st three-way valve and the 2 nd three-way valve have their 3 rd openings connected to the 2 nd connecting pipe. The 1 st three-way valve and the 2 nd three-way valve are switched to any one of a 1 st state in which the spool is located at a 1 st position, a 2 nd state in which the spool is located at a 2 nd position, and a 3 rd state in which the spool is located at a 3 rd position, independently of each other. In each of the 1 st and 2 nd three-way valves, a 1 st space, which is communicated with the 1 st and 2 nd opening portions and is partitioned from the 3 rd opening portion, is disposed in the valve housing in a 1 st state, a 2 nd space, which is communicated with the 1 st, 2 nd and 3 rd opening portions, is disposed in the valve housing in a 2 nd state, and a 3 rd space, which is communicated with the 1 st and 3 rd opening portions and is partitioned from the 2 nd opening portion, is disposed in the valve housing in a 3 rd state.

Effects of the invention

The present disclosure can provide a refrigeration cycle apparatus that suppresses the occurrence of self-excited vibration while preventing a reduction in comfort when the load on an indoor heat exchanger is reduced.

Drawings

Fig. 1 is a diagram showing a refrigerant circuit of a refrigeration cycle apparatus according to the present embodiment.

Fig. 2 is a cross-sectional view showing a valve seat, a valve housing, and a valve body when the 1 st three-way valve of the present embodiment is in the 1 st state.

Fig. 3 is a sectional view as viewed from an arrow III-III shown in fig. 2.

Fig. 4 is a cross-sectional view showing a valve seat, a valve housing, and a valve body when the 1 st three-way valve of the present embodiment is in the 2 nd state.

Fig. 5 is a sectional view as viewed from an arrow V-V shown in fig. 4.

Fig. 6 is a cross-sectional view showing a valve seat, a valve housing, and a valve body when the 1 st three-way valve of the present embodiment is in the 3 rd state.

Fig. 7 is a sectional view as viewed from arrows VII-VII shown in fig. 6.

Fig. 8 is a diagram showing the refrigerant circuit in the refrigeration cycle apparatus of the present embodiment in the cooling only operation state.

Fig. 9 is a diagram showing the refrigerant circuit when the load on the 1 st indoor heat exchanger is lower than that in the state shown in fig. 8 when the refrigeration cycle apparatus of the present embodiment is in the cooling only operation state.

Fig. 10 is a diagram showing the refrigerant circuit in the refrigeration cycle apparatus of the present embodiment in the heating only operation state.

Fig. 11 is a diagram showing the refrigerant circuit when the refrigeration cycle apparatus of the present embodiment is in the heating only operation state and the load on the 1 st indoor heat exchanger is lower than that in the state shown in fig. 10.

Fig. 12 is a diagram showing the refrigerant circuit in the refrigeration cycle apparatus of the present embodiment in the 1 st cooling-main operation state.

Fig. 13 is a diagram showing the refrigerant circuit in the refrigeration cycle apparatus of the present embodiment in the 1 st heating-main operation state.

Fig. 14 is a cross-sectional view showing a valve seat, a valve housing, and a valve body in the 1 st state of a modification of the 1 st three-way valve shown in fig. 2.

Fig. 15 is a cross-sectional view showing a valve seat, a valve housing, and a valve body in a state 2 of a modification of the 1 st three-way valve shown in fig. 2.

Fig. 16 is a cross-sectional view showing a valve seat, a valve housing, and a valve body in a state 3 of a modification of the 1 st three-way valve shown in fig. 2.

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the following drawings, the same or equivalent portions are denoted by the same reference numerals, and description thereof will not be repeated.

< construction of refrigeration cycle apparatus >

As shown in fig. 1, the refrigeration cycle apparatus 1000 of the present embodiment includes a refrigerant circuit through which a refrigerant circulates. The refrigerant circuit includes a compressor 1, a four-way valve 2 as a flow path switching unit, an outdoor heat exchanger 3, a 1 st pressure reducing device 4A, a 2 nd pressure reducing device 4B, a 1 st indoor heat exchanger 5A, a 2 nd indoor heat exchanger 5B, a 1 st check valve 6A, a 2 nd check valve 6B, a 3 rd check valve 6C, a 4 th check valve 6D, a gas-liquid separator 7, a 1 st three-way valve 8A, a 2 nd three-way valve 9A, a 3 rd three-way valve 8B, a 4 th three-way valve 9B, a 1 st connection pipe 10, a 2 nd connection pipe 11, a 3 rd connection pipe 12A, a 4 th connection pipe 13A, a 5 th connection pipe 12B, and a 6 th connection pipe 13B.

The compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the 1 st check valve 6A, the 2 nd check valve 6B, the 3 rd check valve 6C, and the 4 th check valve 6D are housed in the outdoor unit 100. The 1 st pressure reducer 4A and the 1 st indoor heat exchanger 5A are housed in the 1 st indoor unit 200A. The 2 nd pressure reducing device 4B and the 2 nd indoor heat exchanger 5B are housed in the 2 nd indoor unit 200B. The gas-liquid separator 7, the 1 st three-way valve 8A, the 2 nd three-way valve 9A, the 3 rd three-way valve 8B, and the 4 th three-way valve 9B are housed in the relay 300.

The 1 st connecting pipe 10 and the 2 nd connecting pipe 11 are disposed between the outdoor unit 100 and the relay unit 300 and connected to each other. The 3 rd and 4

th connection pipes

12A and 13A are disposed between and connected to the 1 st indoor unit 200A and the relay unit 300. The 5 th and 6

th connection pipes

12B and 13B are disposed between and connected to the 2 nd indoor unit 200B and the relay unit 300.

The compressor 1 has a discharge port for discharging refrigerant and a suction port for sucking refrigerant. The compressor 1 is, for example, a constant speed compressor having a fixed driving frequency. The compressor 1 is an inverter compressor that performs inverter control of a drive frequency, for example.

The four-way valve 2 has ports 1 to 4. The 1 st port is connected to a discharge port of the compressor 1. The 2 nd port is connected to the suction port of the compressor 1. The 3 rd port is connected to the 1 st connection pipe 10 via the outdoor heat exchanger 3 and the 1 st check valve 6A, and is connected to the 2 nd connection pipe 11 via the outdoor heat exchanger 3 and the 2 nd check valve 6B. The 4 th port is connected to the 1 st connecting pipe 10 via a 3 rd check valve 6C and to the 2 nd connecting pipe 11 via a 4 th check valve 6D. The four-way valve 2 switches between a cooling operation state in which the 1 st port communicates with the 3 rd port and the 2 nd port communicates with the 4 th port, and a heating operation state in which the 1 st port communicates with the 4 th port and the 2 nd port communicates with the 3 rd port.

In the outdoor heat exchanger 3, the refrigerant circulating in the refrigerant circuit exchanges heat with outdoor air. The 1 st and 2 nd

pressure reducing devices

4A and 4B are, for example, expansion valves. The refrigerant is expanded in the 1 st pressure reducing device 4A and the 2 nd pressure reducing device 4B. In the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B, the refrigerant circulating in the refrigerant circuit exchanges heat with indoor air. The 1 st indoor unit 200A and the 2 nd indoor unit 200B are disposed in different living rooms, for example.

A refrigerant flow path connecting the outdoor heat exchanger 3 and the 1 st connecting pipe 10, a refrigerant flow path connecting the outdoor heat exchanger 3 and the 2 nd connecting pipe 11, a refrigerant flow path connecting the 4 th port of the four-way valve 2 and the 1 st connecting pipe 10, and a refrigerant flow path connecting the 4 th port of the four-way valve 2 and the 2 nd connecting pipe 11 are formed in the outdoor unit 100.

The 1 st check valve 6A is disposed in the refrigerant flow path between the outdoor heat exchanger 3 and the 1 st connecting pipe 10, and allows only the refrigerant flowing from the outdoor heat exchanger 3 to the 1 st connecting pipe 10 to flow therethrough. The 1 st check valve 6A blocks the flow of the refrigerant flowing from the 1 st connecting pipe 10 to the outdoor heat exchanger 3.

The 2 nd check valve 6B is disposed in the refrigerant flow path between the outdoor heat exchanger 3 and the 2 nd connecting pipe 11, and allows only the refrigerant flowing from the 2 nd connecting pipe 11 to the outdoor heat exchanger to flow. The 2 nd check valve 6B blocks the flow of the refrigerant flowing from the 2 nd connecting pipe 11 to the outdoor heat exchanger 3.

The 3 rd check valve 6C is disposed in the refrigerant flow path between the 4 th port of the four-way valve 2 and the 1 st connecting pipe 10, and allows only the refrigerant flowing from the 4 th port of the four-way valve 2 to the 2 nd connecting pipe to flow. The 3 rd check valve 6C blocks the flow of the refrigerant flowing from the 1 st connecting pipe 10 to the 4 th port of the four-way valve 2.

The 4 th check valve 6D is disposed in the refrigerant flow path between the 4 th port of the four-way valve 2 and the 2 nd connecting pipe 11, and allows only the refrigerant flowing from the 2 nd connecting pipe 11 to the 4 th port of the four-way valve 2 to flow. The 4 th check valve 6D blocks the flow of the refrigerant flowing from the 4 th port of the four-way valve 2 to the 2 nd connection pipe 11.

The gas-liquid separator 7 has an inlet 71 connected to the 1 st connecting pipe 10 and into which the refrigerant flows, a 1 st outlet 72 through which the gas-phase refrigerant flows out, and a 2 nd outlet 73 through which the liquid-phase refrigerant flows out.

The 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9B are identical in structure to each other. As shown in fig. 2 to 7, the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B include a valve seat 14 and a valve body 15, respectively.

Each valve seat 14 of the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B includes a valve housing 16, and a 1 st, 2 nd, and 3 rd opening portions P1, P2, and P3 that communicate with the valve housing 16.

The valve seat 14 has a 1 st surface 14A and a 2 nd surface 14B, the 1 st surface 14A faces the valve housing 16, and one end of each of the 1 st opening P1 and the 3 rd opening P3 is disposed, and the 2 nd surface 14B has one end of the 2 nd opening P2 disposed. The 1 st opening P1 is arranged in the 1 st direction in the circumferential direction at an interval from the 3 rd opening P3. The opening area of the 3 rd opening P3 is equal to the opening area of the 1 st opening P1, for example. The 2 nd surface 14B faces the 1 st surface 14A across the valve body 15 in, for example, the Z direction which is the 2 nd direction. The 2 nd opening P2 is disposed so as to overlap with the rotation axis of the valve body 15 when viewed from the Z direction, for example. The shortest distance between the respective centers of the 2 nd opening P2 and the 1 st opening P1 is equal to the shortest distance between the respective centers of the 2 nd opening P2 and the 3 rd opening P3, for example, when viewed in the Z direction.

The 1 st opening P1 of the 1 st three-way valve 8A is connected to the 1 st indoor heat exchanger 5A via the 3 rd connecting pipe 12A. The 2 nd opening P2 of the 1 st three-way valve 8A is connected to the 1 st outflow port 72 of the gas-liquid separator 7. That is, the 2 nd opening P2 of the 1 st three-way valve 8A is connected to the 1 st connecting pipe 10 via the gas-liquid separator 7. The 3 rd opening P3 of the 1 st three-way valve 8A is connected to the 2 nd connecting pipe 11.

The 1 st opening P1 of the 2 nd three-way valve 9A is connected to the 1 st indoor heat exchanger 5A via the 4 th connecting pipe 13A. The 2 nd opening P2 of the 2 nd three-way valve 9A is connected to the 2 nd outlet 73 of the gas-liquid separator 7. That is, the 2 nd opening P2 of the 2 nd three-way valve 9A is connected to the 1 st connecting pipe 10 by the gas-liquid separator 7. The 3 rd opening P3 of the 2 nd three-way valve 9A is connected to the 2 nd connecting pipe 11.

The 1 st opening P1 of the 3 rd three-way valve 8B is connected to the 2 nd indoor heat exchanger 5B via the 5 th connecting pipe 12B. The 2 nd opening P2 of the 3 rd three-way valve 8B is connected to the 1 st outflow port 72 of the gas-liquid separator 7. That is, the 2 nd opening P2 of the 3 rd three-way valve 8B is connected to the 1 st connecting pipe 10 by the gas-liquid separator 7. The 3 rd opening P3 of the 3 rd three-way valve 8B is connected to the 2 nd connecting pipe 11.

The 1 st opening P1 of the 4 th three-way valve 9B is connected to the 2 nd indoor heat exchanger 5B via the 6 th connecting pipe 13B. The 2 nd opening P2 of the 4 th three-way valve 9B is connected to the 2 nd outlet 73 of the gas-liquid separator 7. That is, the 2 nd opening P2 of the 4 th three-way valve 9B is connected to the 1 st connecting pipe 10 by the gas-liquid separator 7. The 3 rd opening P3 of the 4 th three-way valve 9B is connected to the 2 nd connecting pipe 11.

The 2 nd opening P2 of the 1 st three-way valve 8A and the 2 nd opening P2 of the 3 rd three-way valve 8B are connected in parallel to the 1 st outflow port 72 of the gas-liquid separator 7 and the 1 st connecting pipe 10. The 3 rd opening P3 of the 1 st three-way valve 8A and the 3 rd opening P3 of the 3 rd three-way valve 8B are connected in parallel to each other to the 2 nd connecting pipe 11.

The 2 nd opening P2 of the 2 nd three-way valve 9A and the 2 nd opening P2 of the 4 th three-way valve 9B are connected in parallel to each other to the 2 nd outlet 73 of the gas-liquid separator 7 and the 1 st connecting pipe 10. The 3 rd opening P3 of the 2 nd three-way valve 9A and the 3 rd opening P3 of the 4 th three-way valve 9B are connected in parallel to each other to the 2 nd connecting pipe 11.

Each spool 15 of the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B moves between the 1 st, 2 nd, and 3 rd positions within the valve housing 16. The valve body 15 is provided to rotate around a rotation axis extending in the Z direction, for example. The valve body 15 rotates in the circumferential direction from the 3 rd opening P3 to the 1 st opening P1 and in the opposite direction to the circumferential direction, for example. The valve body 15 is connected to a rotation shaft of a motor, not shown, via a gear 17, for example. The valve body 15 has a 3 rd surface 18, a recess 19, and a 4 th surface 20, the 3 rd surface 18 slides on the 1 st surface 14A, the recess 19 is arranged in a circumferential direction as a 1 st direction in parallel with the 3 rd surface 18 and is recessed with respect to the 3 rd surface 18, and the 4 th surface 20 is located on a side opposite to the 3 rd surface 18 and faces the 2 nd surface 14B of the valve seat 14 with a space therebetween in the Z direction.

The spool 15 has a 1 st end portion 151 in the circumferential direction and a 2 nd end portion 152 located on the opposite side of the 1 st end portion 151 in the circumferential direction. The 1 st end 151 is an end located forward of the 2 nd end 152 when the valve body 15 rotates in the circumferential direction from the 3 rd opening P3 to the 1 st opening P1. The 2 nd end 152 is an end disposed forward of the 1 st end 151 when the valve body 15 rotates in the circumferential direction from the 1 st opening P1 to the 3 rd opening P3.

The recess 19 has a circumferential 3 rd end 191 and a 4 th end 192 located on the opposite side of the 3 rd end 191 in the circumferential direction. The 3 rd end 191 is an end disposed rearward of the 1 st end 151 and forward of the 4 th end 192 when the valve body 15 rotates in the circumferential direction from the 3 rd opening P3 to the 1 st opening P1. The 4 th end 192 is an end disposed rearward of the 2 nd end 152 and forward of the 3 rd end 191 when the valve body 15 rotates in the circumferential direction from the 1 st opening P1 to the 3 rd opening P3.

The circumferential interval between the 1 st end 151 and the 3 rd end 191 is wider than the circumferential interval between the 2 nd end 152 and the 4 th end 192. The 3 rd surface 18 is disposed at least circumferentially between the 1 st end 151 and the 3 rd end 191 and around the entire circumference of the recess 19.

As shown in fig. 4, when the valve body 15 is in the 2 nd position, the valve body 15 is provided so as not to overlap at least a part of each of the 1 st opening P1 and the 3 rd opening P3 when viewed from the 2 nd opening P2 side. As shown by the broken line in fig. 4, when the valve body 15 is in the 2 nd position, the valve body 15 is disposed so as not to overlap with the 1 st opening P1 and the 3 rd opening P3, for example, as viewed from the 2 nd opening P2 side. The valve body 15 is provided so that the 2 nd space S2 is connected to the entire 1 st opening P1 and the 3 rd opening P3. An angle θ 1 formed by the 1 st end portion 151 and the 2 nd end portion 152 of the valve body 15 outside the valve body 15 with respect to the rotation axis is equal to, for example, an angle θ 2 formed by a 1 st imaginary line L1 passing through the rotation axis of the valve body 15 and being tangent to the 1 st opening portion P1 and a 2 nd imaginary line L2 passing through the rotation axis of the valve body 15 and being tangent to the 3 rd opening portion P3 with respect to the rotation axis when viewed from the 2 nd opening portion P2 side.

As shown in fig. 6, the recess 19 is provided so that, when the valve body 15 is located at the 3 rd position, the recess 19 overlaps the entire 1 st opening P1 and the 3 rd opening P3 as viewed from the 2 nd opening P2 side. An angle θ 3 formed by the 3 rd end 191 and the 4 th end 192 of the recess 19 with respect to the rotation axis is equal to the angle θ 2, for example.

The 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B can take 3 states, respectively, that is, a 1 st state in which the spool 15 is at the 1 st position, a 2 nd state in which the spool 15 is at the 2 nd position, and a 3 rd state in which the spool 15 is at the 3 rd position. The 1 st, 2 nd, 3 rd and 4 th three-

way valves

8A, 9A, 8B and 9B are switched to any one of the 3 states independently of each other.

As shown in fig. 2 and 3, in the 1 st state, the 1 st space S1 that communicates with the 1 st opening P1 and the 2 nd opening P2 and is partitioned from the 3 rd opening P3 by the valve body 15 is disposed in each valve case 16. In the 1 st state, the valve body 15 does not overlap the 1 st opening P1 in the Z direction. The 3 rd surface 18 of the valve body 15 overlaps the entire 3 rd opening P3 to close the 3 rd opening P3. The recess 19 of the valve body 15 does not overlap the 1 st opening P1 and the 3 rd opening P3. The 3 rd surface 18 is disposed so as to overlap the entire 3 rd opening P3 when viewed from the 2 nd opening P2 side. The 1 st end 151 and the 3 rd end 191 of the valve body 15 are arranged so as to sandwich the 3 rd opening P3 in the circumferential direction when viewed from the 2 nd opening P2 side. The recess 19 is disposed so as not to overlap the 1 st opening P1 and the 3 rd opening P3 when viewed from the 2 nd opening P2 side.

As shown in fig. 4 and 5, in the 2 nd state, the 2 nd space S2 communicating with the 1 st opening P1, the 2 nd opening P2, and the 3 rd opening P3 is disposed in the valve housing 16. The 2 nd space constitutes a flow dividing path or a flow merging path. In the 2 nd state, the valve body 15 does not overlap the 1 st opening P1 in the Z direction. The valve body 15 does not overlap at least a part of the 3 rd opening P3 in the Z direction. The valve body 15 is disposed at, for example, the 2 nd position shown by a solid line in fig. 4. In this case, the 3 rd surface 18 is disposed so as to overlap only a part of the 3 rd opening P3 when viewed from the 2 nd opening P2 side. The area of the 3 rd opening P3 that does not overlap with the valve body 15 is smaller than the area of the 1 st opening P1, for example, when viewed from the 2 nd opening P2 side.

The valve body 15 may be disposed at, for example, the 2 nd position indicated by a broken line in fig. 4. In this case, the 3 rd surface 18 is arranged not to overlap with the 3 rd opening P3, for example, when viewed from the 2 nd opening P2 side.

As shown in fig. 6 and 7, in the 3 rd state, the 3 rd space S3, which communicates with the 1 st opening P1 and the 3 rd opening P3 and is partitioned from the 2 nd opening P2, is disposed in the recess 19 of the valve body 15. In the 3 rd state, the recess 19 of the valve body 15 is disposed so as to overlap the 1 st opening P1 and the 3 rd opening P3 in the Z direction.

< operation of refrigeration cycle apparatus >

The refrigeration cycle apparatus 1000 is switched by the four-way valve 2 between a cooling operation state in which the outdoor heat exchanger 3 functions as a condenser and a heating operation state in which the outdoor heat exchanger 3 functions as an evaporator. The refrigeration cycle apparatus 1000 is switched to the cooling only operation state, the cooling-main operation state, the heating only operation state, or the heating-main operation state by the 1 st three-way valve 8A, the 2 nd three-way valve 9A, the 3 rd three-way valve 8B, and the 4 th three-way valve 9B.

In the cooling only operation state, the refrigeration cycle apparatus 1000 is switched to the 1 st cooling only operation state shown in fig. 8, the 2 nd cooling only operation state shown in fig. 9, and the 3 rd cooling only operation state not shown. Similarly, in the heating only operation state, the refrigeration cycle apparatus 1000 is switched to the 1 st heating only operation state shown in fig. 10, the 2 nd heating only operation state shown in fig. 11, and the 3 rd heating only operation state not shown.

When the respective loads on the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B are relatively high, the 1 st cooling only operation state shown in fig. 8 is achieved. In the 1 st cooling only operation state shown in fig. 8, the 1 st and 3 rd three-

way valves

8A and 8B are set to the 3 rd state, respectively, and the 2 nd and 4 th three-

way valves

9A and 9B are set to the 1 st state, respectively. In the 1 st cooling only operation state shown in fig. 8, the refrigerant flows through the refrigerant circuit described above along the arrows in fig. 8.

The high-pressure gas-phase refrigerant discharged from the compressor 1 is condensed in the outdoor heat exchanger 3 to become a high-pressure liquid-phase refrigerant or a gas-liquid two-phase refrigerant, and flows out to the 1 st connection pipe 10. The high-pressure liquid-phase refrigerant or gas-liquid two-phase refrigerant flowing through the 1 st connecting pipe 10 flows into the gas-liquid separator 7 through the inflow port 71. The high-pressure liquid-phase refrigerant flowing out of the 2 nd outlet 73 is branched in the relay unit 300, reaches the 2 nd openings P2 of the 2 nd three-way valve 9A and the 4 th three-way valve 9B in the 1 st state, flows in the 1 st spaces, and flows out from the 1 st openings P1 to the 4 th connecting pipe 13A or the 6 th connecting pipe 13B. The liquid-phase refrigerant that has passed through the 4 th connection pipe 13A is decompressed by the 1 st decompression device 4A, thereafter evaporated in the 1 st indoor heat exchanger 5A, and flows out to the 3 rd connection pipe 12A as a low-pressure gas-phase refrigerant. The liquid-phase refrigerant having passed through the 6 th connecting pipe 13B is decompressed by the 2 nd decompressor 4B, evaporated in the 2 nd indoor heat exchanger 5B, and flows out to the 5 th connecting pipe 12B as a low-pressure gas-phase refrigerant. The low-pressure gas-phase refrigerant flowing through the 3 rd or 5

th connecting pipe

12A or 12B reaches the 1 st opening P1 of the 1 st and 3 rd three-

way valves

8A and 8B in the 3 rd state, flows through the 3 rd spaces, and then flows out of the 3 rd openings P3. The gas-phase refrigerant flowing out of each of the 3 rd opening portions P3 merges in the relay unit 300 and flows out to the 2 nd connection pipe 11.

In this way, in the 1 st cooling only operation state shown in fig. 8, the refrigerant discharged from the compressor 1 flows through either the 1 st indoor heat exchanger 5A or the 2 nd indoor heat exchanger 5B and is then drawn into the compressor 1.

For example, when the load on only the 1 st indoor heat exchanger 5A is lower than a predetermined value, the 2 nd cooling only operation state shown in fig. 9 is realized. In addition, the load on the 2 nd indoor heat exchanger 5B in the 2 nd cooling only operation state may be lower than the load on the 2 nd indoor heat exchanger 5B in the 1 st cooling only operation state.

In the 2 nd cooling only operation state shown in fig. 9, the 1 st and 3 rd three-

way valves

8A and 8B are set to the 3 rd state, the 4 th three-way valve 9B is set to the 1 st state, and the 2 nd three-way valve 9A is set to the 2 nd state, respectively. That is, the 2 nd cooling only operation state shown in fig. 9 is different from the 1 st cooling only operation state shown in fig. 8 in that the 2 nd three-way valve 9A is set to the 2 nd state. In the 2 nd cooling only operation state shown in fig. 9, the refrigerant flows through the refrigerant circuit described above along the arrows in fig. 9.

The high-pressure liquid-phase refrigerant flowing out of the 2 nd outlet 73 is split in the relay unit 300, and a part thereof reaches the 2 nd opening P2 of the 2 nd three-way valve 9A in the 2 nd state. The high-pressure liquid-phase refrigerant flowing into the 2 nd opening P2 of the 2 nd three-way valve 9A flows through the 2 nd space and is further branched in the valve housing 16. A part of the high-pressure liquid-phase refrigerant flowing into the 2 nd opening P2 of the 2 nd three-way valve 9A flows out from the 3 rd opening P3. The liquid-phase refrigerant flowing out of the 3 rd opening P3 of the 2 nd three-way valve 9A merges with the low-pressure gas-phase refrigerant flowing out of each of the 3 rd openings P3 of the 1 st three-way valve 8A and the 3 rd three-way valve 8B in the relay 300, and flows out to the 2 nd connecting pipe 11. The remaining portion of the high-pressure liquid-phase refrigerant flowing into the 2 nd opening P2 flows out from the 1 st opening P1 to the 4 th connecting pipe 13A, is decompressed in the 1 st decompressor 4A, and is evaporated in the 1 st indoor heat exchanger 5A.

In the 2 nd cooling only operation state shown in fig. 9, the amount of refrigerant flowing through the 1 st indoor heat exchanger 5A is controlled as the ratio of the opening areas of the 1 st opening P1 and the 3 rd opening P3 as viewed from the 2 nd opening P2 side of the 2 nd three-way valve 9A. The above ratio is controlled as the rotation angle of the spool 15 of the 2 nd three-way valve 9A.

For example, in order to set the evaporation temperature in the 1 st indoor heat exchanger 5A to the target evaporation temperature, switching between the 1 st cooling only operation state shown in fig. 8 and the 2 nd cooling only operation state shown in fig. 9 and control of the rotation angle of the valve body 15 of the 2 nd three-way valve 9A in the 2 nd cooling only operation state shown in fig. 9 are performed. When it is determined that the evaporation temperature in the 1 st indoor heat exchanger 5A is lower than the target evaporation temperature, the valve body 15 of the 2 nd three-way valve 9A rotates from the 1 st position to the 2 nd position. For example, the evaporation temperature is measured constantly or periodically by a temperature sensor, not shown, attached to the 1 st indoor heat exchanger 5A. For example, the determination of the evaporation temperature and the control of the rotation angle of the valve body 15 are performed by the control unit 310 at all times or periodically. When switching between the 1 st cooling only operation state and the 2 nd cooling only operation state is performed, the drive frequency of the compressor 1 is fixed, for example. Here, the constant driving frequency means that the maximum value and the minimum value of the driving frequency are within a range of 95% to 105% of the average value.

In this way, in the 2 nd cooling only operation state shown in fig. 9, a part of the refrigerant discharged from the compressor 1 is sucked into the compressor 1 without flowing through either of the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B. Therefore, the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A in the 2 nd cooling only operation state shown in fig. 9 is made smaller than the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A in the 1 st cooling only operation state shown in fig. 8, without reducing the drive frequency of the compressor 1.

When the difference between the evaporation temperature of the 1 st indoor heat exchanger 5A and the target evaporation temperature exceeds a predetermined range, the 1 st cooling only operation state shown in fig. 8 and the 2 nd cooling only operation state shown in fig. 9 may be switched, and the rotation angle of the valve body 15 of the 2 nd three-way valve 9A in the 2 nd cooling only operation state shown in fig. 9 may be controlled.

For example, when only the load on the 2 nd indoor heat exchanger 5B is lower than a predetermined value, the 3 rd cooling only operation state is realized. In the 3 rd cooling only operation state, the 1 st three-way valve 8A and the 3 rd three-way valve 8B are set to the 3 rd state, the 2 nd three-way valve 9A is set to the 1 st state, and the 4 th three-way valve 9B is set to the 2 nd state, respectively. The flow rate of the refrigerant flowing through the 2 nd indoor heat exchanger 5B in the 3 rd cooling only operation state is smaller than the flow rate of the refrigerant flowing through the 2 nd indoor heat exchanger 5B in the 1 st cooling only operation state shown in fig. 8.

When the respective loads on the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B are relatively high, the 1 st heating only operation state shown in fig. 10 is achieved. In the 1 st heating only operation state shown in fig. 10, the 1 st and 3 rd three-

way valves

8A and 8B are set to the 1 st state, and the 2 nd and 4 th three-

way valves

9A and 9B are set to the 3 rd state, respectively. In the 1 st heating only operation state shown in fig. 10, the refrigerant flows through the refrigerant circuit as indicated by the arrows in fig. 10.

The high-pressure gas-phase refrigerant discharged from the compressor 1 passes through the 3 rd check valve 6C and flows out to the 1 st connection pipe 10. The high-pressure gas-phase refrigerant flowing through the 1 st connecting pipe 10 flows into the gas-liquid separator 7 through the inlet 71. The high-pressure gas-phase refrigerant flowing out of the 1 st outlet 72 is branched in the relay unit 300, reaches the 2 nd openings P2 of the 1 st three-way valve 8A and the 3 rd three-way valve 8B in the 1 st state, flows in the 1 st spaces, and flows out from the 1 st openings P1 to the 3 rd connecting pipe 12A or the 5 th connecting pipe 12B. The gas-phase refrigerant flowing through the 3 rd connecting pipe 12A is condensed in the 1 st indoor heat exchanger 5A, is reduced in pressure in the 1 st pressure reducing device 4A, and flows out to the 4 th connecting pipe 13A as a low-pressure gas-liquid two-phase refrigerant. The gas-phase refrigerant that has passed through the 5 th connection pipe 12B is condensed in the 2 nd indoor heat exchanger 5B, is reduced in pressure in the 2 nd pressure reducing device 4B, and then flows out to the 6 th connection pipe 13B as a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-phase refrigerant flowing through the 4 th or 6

th connecting pipe

13A or 13B reaches the 1 st opening P1 of the 2 nd and 4 th three-

way valves

9A and 9B in the 3 rd state, flows through the 3 rd spaces, and then flows out of the 3 rd openings P3. The gas-phase refrigerant flowing out of each of the 3 rd openings P3 merges in the relay unit 300 and flows out to the 2 nd connection pipe 11.

In this way, in the 1 st heating only operation state shown in fig. 10, the refrigerant discharged from the compressor 1 flows through either the 1 st indoor heat exchanger 5A or the 2 nd indoor heat exchanger 5B and is then drawn into the compressor 1.

For example, when the load of only the 1 st indoor heat exchanger 5A is lower than a predetermined value, the 2 nd heating only operation state shown in fig. 11 is realized. In addition, the load of the 2 nd indoor heat exchanger 5B in the 2 nd heating only operation state shown in fig. 11 may be lower than the load in the 1 st heating only operation state.

In the 2 nd heating only operation state shown in fig. 11, the 2 nd and 4 th three-

way valves

9A and 9B are set to the 3 rd state, the 3 rd three-way valve 8B is set to the 1 st state, and the 1 st three-way valve 8A is set to the 2 nd state, respectively. That is, the 2 nd heating only operation state shown in fig. 11 is different from the 1 st heating only operation state shown in fig. 10 in that the 1 st three-way valve 8A is set to the 2 nd state. In the 2 nd heating only operation state shown in fig. 11, the refrigerant flows through the refrigerant circuit as indicated by the arrows in fig. 11.

The high-pressure gas-phase refrigerant flowing out of the 1 st outlet port 72 is split in the relay unit 300, and a part thereof reaches the 2 nd opening P2 of the 1 st three-way valve 8A in the 2 nd state. The high-pressure gas-phase refrigerant flowing into the 2 nd opening P2 of the 1 st three-way valve 8A flows through the 2 nd space, and is further branched in the valve housing 16. A part of the high-pressure gas-phase refrigerant flowing into the 2 nd opening P2 of the 1 st three-way valve 8A flows out from the 3 rd opening P3. The gas-phase refrigerant flowing out of the 3 rd opening P3 of the 1 st three-way valve 8A merges with the low-pressure gas-phase refrigerant flowing out of the 3 rd openings P3 of the 2 nd three-way valve 9A and the 4 th three-way valve 9B in the relay unit 300 and flows out to the 2 nd connecting pipe 11. The remaining portion of the high-pressure gas-phase refrigerant flowing into the 2 nd opening P2 flows out from the 1 st opening P1 to the 3 rd connecting pipe 12A, and is condensed in the 1 st indoor heat exchanger 5A.

In the 2 nd heating only operation state shown in fig. 11, the amount of refrigerant flowing through the 1 st indoor heat exchanger 5A is controlled by the 1 st three-way valve 8A. The higher the ratio of the opening area of the 3 rd opening P3 to the opening area of the 1 st opening P1 of the 1 st three-way valve 8A, the smaller the amount of refrigerant flowing through the 1 st indoor heat exchanger 5A. The above ratio is controlled as the rotation angle of the spool 15 of the 1 st three-way valve 8A.

For example, in order to set the condensation temperature in the 1 st indoor heat exchanger 5A to the target condensation temperature, switching between the 1 st heating only operation state shown in fig. 10 and the 2 nd heating only operation state shown in fig. 11 and control of the rotation angle of the valve body 15 of the 1 st three-way valve 8A in the 2 nd heating only operation state shown in fig. 11 are performed. When it is determined that the condensation temperature in the 1 st indoor heat exchanger 5A is higher than the target condensation temperature, the valve body 15 of the 1 st three-way valve 8A rotates from the 1 st position to the 2 nd position. For example, the condensation temperature is measured constantly or periodically by a temperature sensor, not shown, attached to the 1 st indoor heat exchanger 5A. For example, the determination of the condensation temperature and the control of the rotation angle of the valve body 15 are performed by the control unit 310 at all times or periodically. When switching between the 1 st heating only operation state and the 2 nd heating only operation state is performed, the driving frequency of the compressor 1 is fixed, for example.

In this way, in the 2 nd heating only operation state shown in fig. 11, a part of the refrigerant discharged from the compressor 1 is drawn into the compressor 1 without flowing through either of the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B. Therefore, the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A in the 2 nd heating only operation state shown in fig. 11 is made smaller than the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A in the 1 st heating only operation state shown in fig. 10, without reducing the driving frequency of the compressor 1.

When the difference between the condensation temperature of the 1 st indoor heat exchanger 5A and the target condensation temperature exceeds a predetermined range, the 1 st heating only operation state shown in fig. 10 and the 2 nd heating only operation state shown in fig. 11 may be switched, and the rotation angle of the valve body 15 of the 1 st three-way valve 8A in the 2 nd heating only operation state shown in fig. 11 may be controlled.

For example, when the load of only the 2 nd indoor heat exchanger 5B is lower than a predetermined value, the 3 rd heating only operation state is realized. In the 3 rd heating only operation state, the 2 nd three-way valve 9A and the 4 th three-way valve 9B are set to the 3 rd state, the 1 st three-way valve 8A is set to the 1 st state, and the 3 rd three-way valve 8B is set to the 2 nd state, respectively. The flow rate of the refrigerant flowing to the 2 nd indoor heat exchanger 5B in the 3 rd heating only operation state is smaller than the flow rate of the refrigerant flowing to the 2 nd indoor heat exchanger 5B in the 1 st heating only operation state shown in fig. 10.

In this way, in the refrigeration cycle apparatus 1000, when the load on either one of the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B decreases in the 1 st cooling only operation state, the 2 nd cooling only operation state or the 3 rd cooling only operation state is achieved. Similarly, in the refrigeration cycle apparatus 1000, when the load on either the 1 st indoor heat exchanger 5A or the 2 nd indoor heat exchanger 5B decreases in the 1 st heating only operation state, the 2 nd heating only operation state or the 3 rd heating only operation state is achieved. As a result, in the refrigeration cycle apparatus 1000, since the flow rate of the refrigerant flowing to the indoor heat exchanger in which the load is reduced can be reduced without reducing the drive frequency of the compressor 1, the reduction in comfort in the room in which the indoor unit is disposed is prevented, and the occurrence of self-excited vibration in the 1 st check valve 6A, the 2 nd check valve 6B, the 3 rd check valve 6C, and the 4 th check valve 6D is suppressed.

Further, even if two or more solenoid valves (for example, 8 solenoid valves) are substituted for the 1 st three-way valve 8A, the 2 nd three-way valve 9A, the 3 rd three-way valve 8B, and the 4 th three-way valve 9B, it is possible to switch among the cooling only operation state, the cooling main operation state, the heating only operation state, and the heating main operation state. In this case, the control unit needs to control the movement of each valve body of the 8 solenoid valves in order to perform the switching. In contrast, in the refrigeration cycle apparatus 1000, the control unit 310 can perform the switching by controlling only the movement of each valve element of the 4 three-way valves. Therefore, the number of ports of the controller 310 of the refrigeration cycle apparatus 1000 is reduced compared to a refrigeration cycle apparatus including a plurality of electromagnetic valves instead of the three-way valve.

In the refrigeration cycle apparatus 1000, the valve body 15 may be disposed so as not to overlap the 1 st opening P1 and the 3 rd opening P3 when viewed from the 2 nd opening P2 side. As shown by the broken lines in fig. 4, when the valve body 15 is disposed so as not to overlap the 1 st opening P1 and the 3 rd opening P3 when viewed from the 2 nd opening P2 side in the 2 nd state, the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A is further reduced as compared with a case where the valve body 15 is disposed so as to overlap a part of the 3 rd opening P3 when viewed from the 2 nd opening P2 side in the 2 nd state as shown by the solid lines in fig. 4. From a different point of view, in the former case, the difference between the flow rate of the refrigerant flowing through the 1 st indoor heat exchanger 5A and the flow rate of the refrigerant flowing through the 2 nd indoor heat exchanger 5B is larger than in the latter case. Therefore, in the former case, when the respective loads on the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B are relatively large, the flow rates of the refrigerant flowing through the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B may be appropriately set in accordance with the respective loads.

The refrigeration cycle apparatus 1000 is switched between a 1 st cooling main operation state shown in fig. 12 and a 2 nd cooling main operation state not shown in the drawings in the cooling main operation state. Similarly, the refrigeration cycle apparatus 1000 is switched between the 1 st heating-main operation state shown in fig. 13 and the 2 nd heating-main operation state not shown in the drawings in the heating-main operation state.

When the load on the 1 st indoor heat exchanger 5A functioning as an evaporator is higher than the load on the 2 nd indoor heat exchanger 5B functioning as a condenser, the 1 st cooling main operation state shown in fig. 12 is realized. In the 1 st cooling main operation state, the 1 st three-way valve 8A and the 4 th three-way valve 9B are set to the 3 rd state, the 3 rd three-way valve 8B is set to the 1 st state, and the 2 nd three-way valve 9A is set to the 2 nd state, respectively. When the load on the 2 nd indoor heat exchanger 5B functioning as an evaporator is higher than the load on the 1 st indoor heat exchanger 5A functioning as a condenser, the 2 nd cooling main operation state is realized. In the 2 nd cooling main operation state, the 2 nd and 3 rd three-

way valves

9A and 8B are set to the 3 rd state, the 1 st three-way valve 8A is set to the 1 st state, and the 4 th three-way valve 9B is set to the 2 nd state, respectively.

When the load on the 1 st indoor heat exchanger 5A functioning as a condenser is higher than the load on the 2 nd indoor heat exchanger 5B functioning as an evaporator, the 1 st heating main operation state shown in fig. 13 is achieved. In the 1 st heating main operation state, the 3 rd three-way valve 8B is set to the 3 rd state, the 1 st three-way valves 8A and 4 th three-way valves 9B are set to the 1 st state, and the 2 nd three-way valve 9A is set to the 2 nd state. When the load on the 2 nd indoor heat exchanger 5B functioning as a condenser is higher than the load on the 1 st indoor heat exchanger 5A functioning as an evaporator, the 2 nd heating-main operation state is achieved. In the 2 nd heating-main operation state, the 1 st three-way valve 8A is set to the 3 rd state, the 2 nd three-

way valves

9A and 3 rd three-way valves 8B are set to the 1 st state, and the 4 th three-way valve 9B is set to the 2 nd state.

Modification example

The refrigeration cycle apparatus 1000 may include 3 or more indoor heat exchangers and three-way valves twice as many as the number of the indoor heat exchangers. The refrigeration cycle apparatus 1000 may further include, for example, a 3 rd indoor heat exchanger, a 5 th three-way valve, and a 6 th three-way valve, the 3 rd indoor heat exchanger being connected in parallel to the 1 st indoor heat exchanger 5A and the 2 nd indoor heat exchanger 5B, the 5 th three-way valve being disposed downstream of the 3 rd indoor heat exchanger in the cooling operation state and upstream of the 3 rd indoor heat exchanger in the heating operation state, and the 6 th three-way valve being disposed upstream of the 3 rd indoor heat exchanger in the cooling operation state and downstream of the 3 rd indoor heat exchanger in the heating operation state. The 5 th three-way valve is connected in parallel with the 1 st three-way valve 8A and the 3 rd three-way valve 8B. The 6 th three-way valve is connected in parallel with the 2 nd three-way valve 9A and the 4 th three-way valve 9B.

As shown in fig. 14 to 16, the 1 st opening P1 and the 3 rd opening P3 may be arranged in the 1 st direction, i.e., the X direction, at intervals in the X direction, i.e., the 1 st direction, at each of the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B. In this case, the spools 15 of the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B are arranged to reciprocate in the X direction. The 3 rd surface 18 and the concave portion 19 of each valve element 15 are arranged in the X direction. The interval in the X direction between the 1 st end 151 and the 3 rd end 191 is wider than the interval in the X direction between the 2 nd end 152 and the 4 th end 192.

The 4 th surface 20 of the spool 15 is provided to slide with the 2 nd surface 14B of the valve seat 14, for example. The 2 nd opening P2 is disposed opposite to the 1 st opening P1, for example. The 4 th surface 20 of the valve body 15 may be disposed to face the 2 nd surface 14B of the valve seat 14 with a space therebetween, for example. In this case, each valve seat 14 is provided with a holding portion for holding the state in which the 1 st surface 14A of the valve seat 14 is in contact with the 3 rd surface 18 of the valve body 15.

As shown in fig. 14 to 16, the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B described above can take 3 states, i.e., the 1 st, 2 nd, and 3 rd states, as well as the 1 st, 2 nd, 3 rd, and 4 th three-

way valves

8A, 9A, 8B, and 9B shown in fig. 2 to 7. Therefore, the refrigeration cycle apparatus 1000 including the 1 st three-way valve 8A, the 2 nd three-way valve 9A, the 3 rd three-way valve 8B, and the 4 th three-way valve 9B shown in fig. 14 to 16 can also exhibit the same effects as those of the refrigeration cycle apparatus 1000 including the 1 st three-way valve 8A, the 2 nd three-way valve 9A, the 3 rd three-way valve 8B, and the 4 th three-way valve 9B shown in fig. 2 to 7.

The refrigeration cycle apparatus 1000 may further include a device for preventing backflow to the compressor 1. Such a device is, for example, an accumulator or a heat exchanger that exchanges heat between the refrigerant discharged from the compressor 1 and the refrigerant sucked into the compressor 1.

The embodiments of the present disclosure have been described as above, but the above embodiments may be modified variously. The scope of the present disclosure is not limited to the above-described embodiments. The scope of the present disclosure is indicated by the claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Description of the reference numerals

1. A compressor; 2. a four-way valve; 3. an outdoor heat exchanger; 4A, a 1 st pressure reducing device; 4B, a 2 nd pressure reducing device; 5A, a 1 st indoor heat exchanger; 5B, a 2 nd indoor heat exchanger; 6A, 1 st check valve; 6B, no. 2 check valve; 6C, no. 3 check valve; 6D, 4 th check valve; 7. a gas-liquid separator; 8A, a 1 st three-way valve; 8B, a 3 rd three-way valve; 9A, a 2 nd three-way valve; 9B, a 4 th three-way valve; 10. 1 st connecting piping; 11. a 2 nd connecting pipe; 12A, 3 rd connecting piping; 12B, 5 th connecting piping; 13A, 4 th connection piping; 13B, 6 th connecting piping; 14. a valve seat; 14A, 1 st face; 14B, the 2 nd surface; 15. a valve core; 16. a valve housing; 17. a gear; 18. the 3 rd surface; 19. a recess; 20. the 4 th surface; 71. an inflow port; 72. a 1 st outflow opening; 73. a 2 nd outflow opening; 100. an outdoor unit; 151. 1 st end part; 152. a 2 nd end portion; 191. a 3 rd end part; 192. a 4 th end portion; 200A, 1 st indoor machine; 200B, indoor unit 2; 300. a repeater; 310. a control unit; 1000. a refrigeration cycle device; l1, 1 st imaginary line; l2, 2 nd imaginary line; p1, 1 st opening; p2, 2 nd opening part; p3, 3 rd opening part; s1, a 1 st space; s2, a 2 nd space; and S3, a No. 3 space.

Claims

1. A refrigerating cycle apparatus, wherein,

the refrigeration cycle apparatus includes a refrigerant circuit in which a refrigerant circulates, the refrigerant circuit including a compressor, a flow path switching unit, an outdoor heat exchanger, a pressure reducing device, a 1 st indoor heat exchanger, a 1 st connecting pipe through which a refrigerant flowing into the 1 st indoor heat exchanger flows, and a 2 nd connecting pipe through which a refrigerant flowing out of the 1 st indoor heat exchanger flows,

the flow path switching unit switches between a cooling operation state in which the outdoor heat exchanger functions as a condenser and a heating operation state in which the outdoor heat exchanger functions as an evaporator,

the refrigerant circuit further includes a 1 st three-way valve and a 2 nd three-way valve,

the 1 st three-way valve is disposed downstream of the 1 st indoor heat exchanger in the cooling operation state and upstream of the 1 st indoor heat exchanger in the heating operation state,

the 2 nd three-way valve is disposed upstream of the 1 st indoor heat exchanger in the cooling operation state and is disposed downstream of the 1 st indoor heat exchanger in the heating operation state,

the 1 st three-way valve and the 2 nd three-way valve each include a valve seat including a valve housing and a 1 st opening portion, a 2 nd opening portion, and a 3 rd opening portion connected to the valve housing, and a valve body moving between a 1 st position, a 2 nd position, and a 3 rd position in the valve housing,

the 1 st opening of each of the 1 st and 2 nd three-way valves is connected to one end or the other end of the 1 st indoor heat exchanger in the refrigerant circuit,

the 2 nd opening of each of the 1 st three-way valve and the 2 nd three-way valve is connected to the 1 st connection pipe,

the 1 st opening of the 1 st three-way valve and the 2 nd opening of the 2 nd three-way valve are connected to the 2 nd connecting pipe,

the 1 st three-way valve and the 2 nd three-way valve are switched to any one of a 1 st state in which the spool is located at the 1 st position, a 2 nd state in which the spool is located at the 2 nd position, and a 3 rd state in which the spool is located at the 3 rd position, independently of each other,

in the 1 st state, a 1 st space which communicates with the 1 st opening and the 2 nd opening and is partitioned from the 3 rd opening is disposed in the valve housing,

in the 2 nd state, a 2 nd space communicating with the 1 st opening, the 2 nd opening, and the 3 rd opening is disposed in the valve housing,

in the 3 rd state, a 3 rd space that communicates with the 1 st opening and the 3 rd opening and is partitioned from the 2 nd opening is disposed in the valve housing.

2. The refrigeration cycle apparatus according to claim 1,

the valve seat has a 1 st surface and a 2 nd surface, the 1 st surface facing the valve housing and formed with the 1 st opening portion and the 3 rd opening portion, the 2 nd surface formed with the 2 nd opening portion,

the 1 st opening is arranged in the 1 st direction at a distance from the 3 rd opening,

the valve body has a 3 rd surface and a recess, the 3 rd surface slides with the 1 st surface, the recess is arranged in line with the 3 rd surface along the 1 st direction and is recessed with respect to the 3 rd surface,

in the 1 st state, the 3 rd surface is disposed so as to overlap the 3 rd opening, and the recess is disposed so as not to overlap the 1 st opening and the 3 rd opening when viewed from the 2 nd opening side,

in the 3 rd state, the recess is disposed so as to overlap the 1 st opening and the 3 rd opening, and the 3 rd space is formed in the recess.

3. The refrigeration cycle apparatus according to claim 2,

the 2 nd surface and the 1 st surface are opposite to each other with the valve core sandwiched therebetween,

the spool is provided to rotate about a rotation axis extending in a 2 nd direction,

the 1 st direction is a circumferential direction with respect to the rotation axis.

4. The refrigerating cycle apparatus according to claim 3,

the valve body is provided so that the 2 nd space is connected to the entire 1 st opening and the 3 rd opening.

5. The refrigeration cycle apparatus according to any one of claims 1 to 4,

the refrigerant circuit further includes a 2 nd indoor heat exchanger, a 3 rd three-way valve and a 4 th three-way valve,

the 2 nd indoor heat exchanger is connected to the 1 st connecting pipe and the 2 nd connecting pipe in parallel with the 1 st indoor heat exchanger,

the 3 rd three-way valve is disposed downstream of the 1 st indoor heat exchanger in the cooling operation state and upstream of the 2 nd indoor heat exchanger in the heating operation state,

the 4 th three-way valve is disposed upstream of the 1 st indoor heat exchanger in the cooling operation state and downstream of the 2 nd indoor heat exchanger in the heating operation state,

the 3 rd and 4 th three-way valves have the same configuration as the 1 st and 2 nd three-way valves, and are switched to any one of the 1 st, 2 nd, and 3 rd states independently of each other,

in the cooling operation state in which the load on the 1 st indoor heat exchanger is lower than the load on the 2 nd indoor heat exchanger, the 1 st and 3 rd three-way valves are set to the 3 rd state, the 2 nd and 4 th three-way valves are set to the 2 nd state and the 1 st state,

in the heating operation state in which the load on the 1 st indoor heat exchanger is lower than the load on the 2 nd indoor heat exchanger, the 2 nd and 4 th three-way valves are set to the 3 rd state, the 1 st three-way valve is set to the 2 nd state, and the 3 rd three-way valve is set to the 1 st state.

6. The refrigeration cycle apparatus according to any one of claims 1 to 5,

when switching between the 1 st state and the 2 nd state is performed, the driving frequency of the compressor is fixed.

7. The refrigeration cycle apparatus according to any one of claims 1 to 6,

the refrigerant circuit further includes a 1 st check valve, a 2 nd check valve, a 3 rd check valve and a 4 th check valve,

the 1 st check valve is disposed in the refrigerant flow path between the outdoor heat exchanger and the 1 st connection pipe, and allows only the refrigerant flowing from the outdoor heat exchanger to the 1 st connection pipe to flow therethrough,

the 2 nd check valve is disposed in the refrigerant flow path between the outdoor heat exchanger and the 2 nd connecting pipe, and allows only the refrigerant flowing from the 2 nd connecting pipe to the outdoor heat exchanger to flow,

the 3 rd check valve is disposed in the refrigerant flow path between the flow path switching unit and the 1 st connection pipe, and allows only the refrigerant flowing from the flow path switching unit to the 1 st connection pipe to flow,

the 4 th check valve is disposed in the refrigerant flow path between the flow path switching unit and the 2 nd connecting pipe, and allows only the refrigerant flowing from the 2 nd connecting pipe to the flow path switching unit to flow.

8. The refrigeration cycle apparatus according to any one of claims 1 to 7,

the refrigerant circuit further includes a gas-liquid separator,

the gas-liquid separator has an inflow port connected to the 1 st connection pipe, a 1 st outflow port connected to the 2 nd opening of the 1 st three-way valve for flowing out the gas-phase refrigerant, and a 2 nd outflow port connected to the 2 nd opening of the 2 nd three-way valve for flowing out the liquid-phase refrigerant.

9. The refrigeration cycle apparatus according to any one of claims 1 to 8,

the 1 st and 2 nd connecting pipes are disposed between an outdoor unit that houses the compressor, the flow path switching unit, and the outdoor heat exchanger, and a relay that houses the 1 st and 2 nd three-way valves.