Abstract: In a method of controlling start of a refrigerant-circulating compressor driven by a brushless motor in a refrigerating cycle, the brushless motor is started in accordance with an asynchronous forced commutation operation without use of rotor position detection signals; and when the rotor position detection signals can be detected a predetermined number of times or more due to synchronous commutations during the forced commutation operation, the asynchronous forced commutation operation is shifted to a synchronous commutation starting operation with the use of the rotor position detection signals.

Abstract: At the time of dehumidifying operation, a motor-operated expansion valve is controlled so that evaporation of a refrigerant will be completed in an auxiliary indoor heat exchanger which constitutes an indoor heat exchanger together with a main indoor heat exchanger. A louver is operated to form an air passage through which air discharged from the outlet port of an indoor unit flows to the inlet port. Owing to the formation of such an air passage from the outlet to the inlet port of the indoor unit, dehumidification is performed with outlet air kept from reaching the living space in the room.

Abstract: An inverter controlling an air conditioner including a brushless motor serving as a compressor motor. A microcomputer detects the rotational position of a rotor of the brushless motor from signals obtained by comparison of each of terminal voltages of the motor windings with a reference voltage in order to determine a commutation time. In a normal operation, the microcomputer forms, according to a normal energization signal forming pattern, energization signals corresponding to every commutation time at every occurrence of the commutation time, so that the motor windings are sequentially energized. When frost forms on an outdoor heat exchanger of a heat pump during a warming operation and a defrosting operation is necessary, the energization signals are formed according to a loss increasing energization signal forming pattern so that loss increasing energization signals for causing the rotor to produce counter torque are added to the respective energization signals formed according to the normal pattern.

Abstract: A double-combustor type pulsating combustion apparatus has a pair of pulsating combustors. Fuel-supplying valves are respectively provided in fuel-supplying pipes connected to the upstream sides of combustion chambers of the pair of pulsating combustors. A combustion control unit controls to stop only one pulsating combustor and to operate only the other pulsating combustor by closing one fuel-supplying valve corresponding to one pulsating combustor in a combustion range of 1/2 or less of the maximum combustion amount of the double-combustor type pulsating combustion apparatus. The combustion control unit further controls to operate both the pulsating combustors by opening both the fuel-supplying valves in a combustion range exceeding 1/2 of the maximum combustion amount.

Abstract: A pulse combustion apparatus comprising a metal pipe member, an exhaust chamber, and an insert member. The pipe member has two open ends and its inner diameter is uniform over its entire length. The first open end of the pipe member is closed, and the second open end thereof is connected to the exhaust chamber. The insert member is located within the pipe member such that it and the pipe member define a combustion chamber within the pipe member, close to the first end thereof, and also an exhaust passage connecting the combustion chamber to the exhaust chamber and having a cross section area smaller than that of the combustion chamber. The combustion chamber and the exhaust passage constitute a Helmholtz resonator which realizes pulse combustion of the fuel gas.

Abstract: A combustion chamber of a pulsating combustor is supplied with fuel from a fuel-supplying system and with air for combustion from an air-intake chamber through an air-intake pipe. The air-intake pipe is interiorly provided with an aerodynamic valve having a forward flow coefficient greater than a flow coefficient in a reversed direction. An air-supplying fan controlled by a combustion control unit is connected to the air-intake chamber. A fuel control valve for varying the amount of fuel supplied to the combustion chamber is connected to a fuel-supplying pipe of a fuel-supplying system. When a mixture gas within the combustion chamber is fired at the start of a pulsating combustion system, the combustion control unit rotates the air-supplying fan at high speed to forcibly feed air for combustion into the combustion chamber.