# US 2016/0238271 A1 · Air conditioner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0238271 A1 - Document ID: US20160238271A1 - Status: Published application - Kind: A1 - Application number: 15/025,358 - Filed: 2014-01-22 - Published: 2016-08-18 - Earliest claimed: 2013-09-30 - Assignees: Fujitsu General Limited - Applicants: Fujitsu General Limited - Inventors: Takashi KIMURA; Kuniko HAYASHI - Web page: https://patentgrep.com/patent/US20160238271A1 ## CPC - F24F 11/77: by controlling the speed of ventilators - F24F 3/065: {with a plurality of evaporators or condensers} - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F25B 47/025: {by reversing the cycle} - F25B 49/02: for compression type machines, plants or systems - F24F 11/42: of outdoor units - F25B 41/34: with the valve member being actuated by electric means, e.g. by piezoelectric actuators - F25B 2313/005: Outdoor unit expansion valves - F25B 2313/006: two pipes connecting the outdoor side to the indoor side with multiple indoor units - F25B 2313/0233: in parallel arrangements - F25B 2313/02741: using one four-way valve - F25B 2313/0294: related to the outdoor fan, e.g. controlling speed - F25B 2313/0315: Temperature sensors near the outdoor heat exchanger - F25B 2600/2513: Expansion valves - F25B 2700/1931: Discharge pressures - F25B 2700/1933: Suction pressures - F25B 2700/2106: of fresh outdoor air - F25B 2700/21151: at the suction side of the compressor - F25B 2700/21152: at the discharge side of the compressor - Y02B 30/70: Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating - 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 - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A CPU 210 receives suction pressure PL and a suction temperature Te, calculates a saturation temperature corresponding to the evaporation pressure Ts1 by using the suction pressure PL, and calculates a suction superheating degree SHs of a compressor 21 by using the suction temperature Te and the saturation temperature corresponding to the evaporation pressure Ts1. The CPU 210 reads a current opening degree De of an outdoor expansion valve 24. Next, the CPU 210 uses the received suction pressure PL and opening degree De of the outdoor expansion valve 24 and the calculated suction superheating degree SHs, refers to an outdoor fan control table 300, and determines a control aspect of an outdoor fan 27. The CPU 210 executes control of the outdoor fan 27 in accordance with the control aspect that is determined by referring to an outdoor fan control table 300. ## Claims ### Claim 1 An air conditioner comprising an indoor unit and an outdoor unit that are coupled by a liquid pipe and a gas pipe, the outdoor unit having a compressor, a flow passage switching unit, an outdoor heat exchanger, an outdoor expansion valve, an outdoor fan, a suction pressure detector, a suction temperature detector, and an outdoor unit controller, the suction pressure detector detecting suction pressure that is pressure of a refrigerant suctioned into the compressor, the suction temperature detector detecting a suction temperature that is a temperature of the refrigerant suctioned into the compressor, and the outdoor unit controller controlling the outdoor fan in accordance with the detected suction pressure when the outdoor heat exchanger functions as an evaporator, wherein the outdoor unit controller calculates a suction superheating degree that is a superheating degree of the refrigerant suctioned into the compressor by using the detected suction pressure and the detected suction temperature, the outdoor unit controller controls the outdoor fan such that the suction pressure becomes equal to or more than first threshold pressure that is higher by a predetermined value than evaporation pressure and lower than second threshold pressure that is higher than the same first threshold pressure when the suction superheating degree is equal to or less than a predetermined threshold superheating degree, the evaporation pressure corresponding to a temperature of the outdoor heat exchanger at which the outdoor heat exchanger is frosted, and the outdoor unit controller controls the outdoor fan such that the suction superheating degree becomes equal to or less than the threshold superheating degree when the suction superheating degree is higher than the threshold superheating degree and the suction pressure is lower than the second threshold pressure. ### Claim 2 (depends on 1) The air conditioner according to claim 1, wherein the outdoor unit controller increases a rotational speed of the outdoor fan in the case where the suction pressure is lower than the first threshold pressure, maintains the rotational speed of the outdoor fan at a current rotational speed in the case where the suction pressure is equal to or more than the first threshold pressure and lower than the second threshold pressure, and reduces the rotational speed of the outdoor fan in the case where the suction pressure is equal to or more than the second threshold pressure, when the suction superheating degree is equal to or less than the threshold superheating degree, and the outdoor unit controller reduces the rotational speed of the outdoor fan in the case where an opening degree of the outdoor expansion valve is full open, and maintains the rotational speed of the outdoor fan at the current rotational speed in the case where the opening degree of the outdoor expansion valve is not full open, when the suction superheating degree is higher than the threshold superheating degree and the suction pressure is lower than the second threshold pressure.