# US 11,079,129 B2 · Air conditioner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,129 B2 - Document ID: US11079129B2 - Status: Granted - Kind: B2 - Application number: 16/486,081 - Filed: 2018-02-06 - Published: 2020-01-16 - Granted: 2021-08-03 - Earliest claimed: 2017-02-14 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Daehyoung Kim; Junseong Park; Jaehwa Jung - Web page: https://patentgrep.com/patent/US11079129B2 ## CPC - F24F 11/65: for selecting an operating mode - F24F 3/065: {with a plurality of evaporators or condensers} - F24F 11/30: for purposes related to the operation of the system, e.g. for safety or monitoring - F24F 11/84: using valves - F25B 1/10: with multi-stage compression (with cascade operation F25B7/00) - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F25B 40/00: Subcoolers, desuperheaters or superheaters - F25B 41/20: Disposition of valves, e.g. of on-off valves or flow control valves (expansion valves F25B41/31) - F25B 49/02: for compression type machines, plants or systems - F25B 2313/007: three pipes connecting the outdoor side to the indoor side with multiple indoor units - F25B 2313/009: indoor unit in circulation with outdoor unit in first operation mode, indoor unit in circulation with an other heat exchanger in second operation mode or outdoor unit in circulation with an other heat exchanger in third operation mode - F25B 2313/025: using multiple outdoor units - F25B 2313/0253: in parallel arrangements - F25B 2313/0254: in series arrangements - F25B 2313/02742: using two four-way valves - F25B 2400/075: with parallel compressors - F25B 2400/13: Economisers - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS ## Abstract An air conditioner is disclosed. The air conditioner comprises: an indoor unit having an indoor heat exchanger installed therein; a first outdoor unit having a first outdoor heat exchanger and a first compressor installed therein; a second outdoor unit having a second outdoor heat exchanger and a second compressor installed therein; an auxiliary module which connects the indoor unit, the first outdoor unit, and the second outdoor unit; a first connection line by which the auxiliary module is connected to the first outdoor unit; a second connection line by which the auxiliary module is connected to the second outdoor unit; and a two-stage compression line by which the first outdoor unit is connected to the second outdoor unit. ## Claims ### Claim 1 An air conditioner comprising: an indoor unit having an indoor heat exchanger installed therein; a first outdoor unit having a first outdoor heat exchanger and a first compressor installed therein; a second outdoor unit having a second outdoor heat exchanger and a second compressor installed therein; an auxiliary module configured to connect the indoor unit, the first outdoor unit, and the second outdoor unit to each other; a first connection line to which the auxiliary module and the first outdoor unit are connected; a second connection line to which the auxiliary module and the second outdoor unit are connected; and a two-stage compression line configured to connect the first outdoor unit and the second outdoor unit to each other, wherein the two-stage compression line includes: a first two-stage compression line configured to allow a refrigerant that exchanges heat by the second outdoor heat exchanger to flow to the first outdoor unit; and a second two-stage compression line configured to allow a refrigerant compressed by the first compressor to flow to the second outdoor unit, wherein the first connection line includes a first heat exchanger input and output line to which the auxiliary module and the first outdoor heat exchanger are connected, wherein the auxiliary module further includes an auxiliary module injection line configured to connect the first heat exchanger input and output line and the second two-stage compression line to each other, and wherein the auxiliary module injection line includes installed therein: an auxiliary module injection expansion valve configured to expand a refrigerant flowing in the auxiliary module injection line from the first heat exchanger input and output line; and an auxiliary module injection heat exchanger configured to exchange heat between a transmitted through the auxiliary module injection expansion valve and a refrigerant flowing in the first heat exchanger input and output line. ### Claim 2 (depends on 1) The air conditioner of claim 1, wherein the auxiliary module includes an auxiliary module valve installed to open the first connection line and to allow a refrigerant to flow to the indoor unit through the first connection line and the second connection line in a one-stage heating mode, and to close the first connection line and to allow the refrigerant to the indoor unit through only the second connection line in a two-stage heating mode. ### Claim 3 (depends on 2) The air conditioner of claim 2, wherein the refrigerant flowing in the first connection line and the second connection line is compressed by the first compressor and the second compressor, respectively, and flows to the auxiliary module along the first connection line and the second connection line, in the one-stage heating mode; and wherein the refrigerant flowing in the first connection line and the second connection line is compressed by the first compressor and the second compressor, sequentially, and flows to the auxiliary module along the second connection line, in the two-stage heating mode. ### Claim 4 (depends on 1) The air conditioner of claim 1, wherein the first outdoor unit includes a first main four-way valve and a first auxiliary four-way valve; wherein the second outdoor unit includes a second main four-way valve and a second auxiliary four-way valve; and wherein, when a one-stage heating mode and a two-stage heating mode are switched with each other, any one of the first main four-way valve and the first auxiliary four-way valve, and any one of the second main four-way valve and the second auxiliary four-way valve are configured to reverse the flow therethrough. ### Claim 5 (depends on 4) The air conditioner of claim 4, wherein the first auxiliary four-way valve is disposed to allow a refrigerant transmitted through the first compressor to flow to the indoor unit, in the one-stage heating mode; and wherein the first auxiliary four-way valve is disposed to allow a refrigerant transmitted through the first compressor to flow to the second outdoor unit, in the two-stage heating mode. ### Claim 6 (depends on 4) The air conditioner of claim 4, wherein the second main four-way valve is disposed to allow a refrigerant transmitted through the second outdoor heat exchanger to flow to the second compressor, in the one-stage heating mode; and wherein the second main four-way valve is disposed to allow a refrigerant transmitted through the second outdoor heat exchanger to flow to the first outdoor unit, in the two-stage heating mode. ### Claim 7 (depends on 1) The air conditioner of claim 1, wherein the second two-stage compression line penetrates the auxiliary module and extends to the second outdoor unit.