Abstract: A cogeneration system including an engine, which drives a generator to generate electricity, a cooling/heating unit, which comprises at least one compressor, a four-way valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, to establish a heat pump type refrigerant cycle, a cooling water heat supplier to supply heat of cooling water used to cool the engine to a suction side of the compressor of the cooling/heating unit and to pre-heat air passing through the outdoor heat exchanger, and a discharge-side refrigerant over-heater to supply heat of exhaust gas discharged from the engine to a discharge side of the compressor. In accordance with the cogeneration system, it is possible to maximize absorption of the waste heat of the engine while preventing compressor malfunction, and thus, to increase the refrigerant condensing temperature of the indoor heat exchanger and the refrigerant pre-heating temperature of the outdoor heat exchanger.

Abstract: A cogeneration system including an engine, which drives a generator to generate electricity, a cooling/heating unit, which comprises at least one compressor, a four-way valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, to establish a heat pump type refrigerant cycle, and an exhaust heat consuming heating unit to supply heat of exhaust gas discharged from the engine to a heat exchanging zone of the indoor heat exchanger of the cooling/heating unit, and thus, to heat a confined space. Since waste heat generated from the engine is directly used in the cooling/heating unit, an enhancement in indoor heating efficiency is achieved.

Abstract: A cogeneration system including an engine, which drives a generator to generate electricity, a cooling/heating unit, which includes at least one compressor, a four-way valve, an outdoor heat exchanger, an expansion device, and an indoor heat exchanger, to establish a heat pump type refrigerant cycle, and a refrigerant over-heating unit to supply heat of cooling water used to cool the engine to a suction-side refrigerant line of the compressor of the cooling/heating unit, and to supply heat of exhaust gas discharged from the engine to the suction-side refrigerant line of the compressor and to a discharge-side refrigerant line of the compressor. In accordance with the cogeneration system, it is possible to maximize absorption of the waste heat of the engine while preventing compressor malfunction, and thus, to increase the refrigerant condensing temperature of the indoor heat exchanger. Thus, an enhancement in heating performance is achieved.

Abstract: An air-conditioner having multiple compressors includes: an indoor heat-exchanger disposed indoors and heat-exchanging indoor air; an outdoor heat-exchanger disposed outdoors and heat-exchanging a refrigerant with external air; four compressors for compressing the refrigerant to change the refrigerant to have a high temperature and high pressure; and three accumulators disposed at a suction side of the four compressors and separating the refrigerant into a gas and a liquid to supply a gaseous refrigerant to the compressors. Oil can be uniformly supplied to each compressor, thereby enhancing reliability of compressors, and since the three accumulators are small with low capacities, their installation space can be easily secured.

Abstract: In a heater system for a microwave oven including an air tunnel having an suction portion and a discharge portion, formed at an upper surface of a cooking chamber, a fan assembly installed inside the air tunnel and having a circulation fan forming air flow by sucking air inside the cooking chamber through the suction portion and discharge the sucked air through the air tunnel and the discharge portion, a first heater chamber having a first heater installed inside the air tunnel and heating air discharged into the discharge portion from the air tunnel, and a second heater chamber having a second heater installed inside the air tunnel and emitting radiation heat into the cooking chamber, wherein the suction portion and the discharge portion are formed near opposite side walls of the cooking chamber.

Abstract: In a heater system for a microwave oven including an air tunnel having an suction portion and a discharge portion, formed at an upper surface of a cooking chamber, a fan assembly installed inside the air tunnel and having a circulation fan forming air flow by sucking air inside the cooking chamber through the suction portion and discharge the sucked air through the air tunnel and the discharge portion, a first heater chamber having a first heater installed inside the air tunnel and heating air discharged into the discharge portion from the air tunnel, and a second heater chamber having a second heater installed inside the air tunnel and emitting radiation heat into the cooking chamber, wherein the suction portion and the discharge portion are respectively formed at each end portions of the upper surface of the cooking chamber, said end portions facing each other and positioned toward the side walls of the cooking chamber.