# US 2019/0170378 A1 · Regenerative air conditioner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170378 A1 - Document ID: US20190170378A1 - Status: Published application - Kind: A1 - Application number: 16/256,548 - Filed: 2019-01-24 - Published: 2019-06-06 - Earliest claimed: 2014-12-26 - Assignees: Daikin Industries, Ltd. - Applicants: Daikin Industries, Ltd. - Inventors: Kouichi YASUO; Shuuji FUJIMOTO; Kebi CHEN; Takuya NAKAO - Web page: https://patentgrep.com/patent/US20190170378A1 ## CPC - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F24F 5/00: Air-conditioning systems or apparatus not covered by F24F1/00 or F24F3/00 {, e.g. using solar heat or combined with household units such as an oven or water heater} - F24F 5/001: {Compression cycle type} - F24F 5/0017: {using cold storage bodies, e.g. ice} - F24F 11/89: Arrangement or mounting of control or safety devices - F25B 41/20: Disposition of valves, e.g. of on-off valves or flow control valves (expansion valves F25B41/31) - F25B 41/24: Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part - F25B 49/022: {Compressor control arrangements} - F25B 2313/006: two 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 2313/0232: with bypasses - F25B 2313/0233: in parallel arrangements - F25B 2313/02731: using one three-way valve - F25B 2400/13: Economisers - F25B 2400/24: Thermal storage element - F25B 2600/0253: with variable speed - Y02B 30/70: Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating - Y02E 60/14: Thermal energy storage - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract To avoid decline in the efficiency of a compressor at a low load, a thermal storage air conditioner has a refrigerant circuit (11) which has a compressor (22), an outdoor heat exchanger (23), and an indoor heat exchanger (72) and performs a refrigeration cycle, and a thermal storage section (60) which has a thermal storage medium and exchanges heat between the thermal storage medium and a refrigerant of the refrigerant circuit (11). The thermal storage air conditioner performs a simple cooling operation in which in the refrigerant circuit (11), the refrigerant is condensed in the outdoor heat exchanger (23) and evaporates in the indoor heat exchanger (72), and a cooling and cold thermal energy storage operation in which in the refrigerant circuit (11), the refrigerant is condensed in the outdoor heat exchanger (23) and evaporates in the indoor heat exchanger (72), and in which the thermal storage medium in the thermal storage section (60) is cooled by the refrigerant. The thermal storage air conditioner has an operation control section (100) which, if a rotational speed of the compressor (22) is slowed down to a predetermined lower reference value in the simple cooling operation, switches an operation of the thermal storage air conditioner from the simple cooling operation to the cooling and cold thermal energy storage operation to increase the rotational speed of the compressor (22). ## Claims ### Claim 1 A thermal storage air conditioner, comprising: a refrigerant circuit which has a compressor, an outdoor heat exchanger, and an indoor heat exchanger and performs a refrigeration cycle; and a thermal storage section which has a thermal storage medium and exchanges heat between the thermal storage medium and a refrigerant of the refrigerant circuit, the thermal storage air conditioner being capable of performing a simple heating operation in which in the refrigerant circuit, the refrigerant is condensed in the indoor heat exchanger and evaporates in the outdoor heat exchanger, and a heating and warm thermal energy storage operation in which in the refrigerant circuit, the refrigerant is condensed in the indoor heat exchanger and evaporates in the outdoor heat exchanger, and in which the thermal storage medium in the thermal storage section is heated by the refrigerant, wherein the thermal storage air conditioner has an operation control section which, if a rotational speed of the compressor is slowed down to a predetermined lower reference value in the simple heating operation, switches an operation of the thermal storage air conditioner from the simple heating operation to the heating and warm thermal energy storage operation to increase the rotational speed of the compressor. ### Claim 2 (depends on 1) The thermal storage air conditioner of claim 1, wherein the operation control section switches the operation of the thermal storage air conditioner from the heating and warm thermal energy storage operation to the simple heating operation to reduce the rotational speed of the compressor if the rotational speed of the compressor increases to a predetermined upper reference value in the heating and warm thermal energy storage operation. ### Claim 3 (depends on 1) The thermal storage air conditioner of claim 1, wherein when the operation control section switches the operation of the thermal storage air conditioner from the simple heating operation to the heating and warm thermal energy storage operation, the rotational speed of the compressor is increased by a value equal to a lowest rotational speed of the compressor. ### Claim 4 (depends on 2) The thermal storage air conditioner of claim 2, wherein when the operation control section switches the operation of the thermal storage air conditioner from the simple heating operation to the heating and warm thermal energy storage operation, the rotational speed of the compressor is increased by a value equal to a lowest rotational speed of the compressor.