Abstract: A DC power supply unit is provided that allows for improving efficiency and reducing harmonic currents. A DC power supply unit includes: a bridge rectification circuit having diodes and MOSFETs; a reactor that is arranged between the AC power supply and the bridge rectifier circuit; a smoothing capacitor that is connected to an output side of the bridge rectifier circuit and smoothes a voltage; and a converter control unit that executes, based on predetermined threshold values, a diode rectification control that uses diodes and parasitic diodes of the MOSFETs, a synchronous rectification control that switches the MOSFETs in synchronization with a polarity of the voltage of the AC power supply, a partial switching control that repeats partially short-circuiting the reactor multiple times in a half cycle of the AC power supply, or a fast switching control that short-circuits the reactor at a predetermined frequency over a full AC cycle.

Abstract: A heat exchanger includes a refrigerant flow path into which a gas refrigerant flows from two gas-side inlets in the second row, that are positioned off from each other. Refrigerant flow paths from the two gas-side inlets converge in the one end portion. The refrigerant flow path connects to a heat-transfer pipe in the first row from the second row. The refrigerant flow path includes a refrigerant flow path which is formed in a range from the same stage as one of the gas-side inlets of the second row to the same stage as the other of the gas-side inlets of the second row, while being arranged along both ways between the one end portion and the other end portion in the first row, and the refrigerant flow path extends to a liquid-side outlet.

Abstract: The air conditioner has a configuration such that, in an air-warming operation: the average refrigerant exit temperature, which is obtained by averaging the temperature of the refrigerant exits of indoor heat exchangers 7 in a plurality of indoor units 10, as detected by heat-exchanger-refrigerant-exit temperature probes 34 in the indoor units 10, is determined; the temperature difference between the average refrigerant exit temperature and the refrigerant exit temperatures of the indoor heat exchangers 7 of each of the indoor units 10 is determined; and the degree to which indoor expansion valves 9 of the indoor units 10 are open is controlled such that the determined temperature difference falls within a predetermined temperature difference range.

Abstract: An outdoor unit (100, 110), comprising a housing (1, 20) having fans (2) provided thereon and a compressor (4) and heat exchanger (3-1, 3-2, 23-1, 23-2) disposed on a base (10, 210) thereof; a left-right pair of side covers (8, 28, 9, 29) each being bent and having two surfaces, one surface covering a portion of a side of housing (1, 20), and the other surface covering a portion of the front of the housing (1, 20); a controller housing (7) fixed to the upper section of the surface of at least one side cover (8, 28, 9, 29), of said left-right pair of said covers (8, 28, 9, 29), that covers a portion of the front of the housing (1, 20), said controller housing (7) being fixed at a height allowing the compressor (4) to be moved into and out of the housing unobstructed.

Abstract: A display device which displays operation information of an air conditioner in which an outdoor machine including an outdoor heat exchanger and an indoor machine including an indoor heat exchanger are connected. The display device includes a control unit that determines whether or not abnormality occurs in the outdoor machine or the indoor machine when the air conditioner operates, and a display unit which is controlled by the control unit so as to display time information and to display a plurality of operation information display regions for displaying operation information corresponding to the time information, in line. In a case where the control unit determines that the abnormality has occurred in the outdoor machine or the indoor machine, the control unit controls the display unit to display operation information of the outdoor machine or the indoor machine in which the abnormality has occurred, in the operation information display region.

Abstract: A refrigeration and air conditioning device, which is an outdoor unit of a refrigeration and air conditioning device provided with a heat exchanger within a housing (2) and blowers (3) arranged on the housing, the housing (2) being provided with a side cover covering the sides, a base (9) covering the bottom and a foot portion (10) arranged below the base (9), the foot portion (10) being provided with a raised portion (10b) upwardly bending an end face (10c) of a lower surface of the foot portion. The refrigeration and air conditioning device increases rigidity without increasing costs.

Abstract: An air conditioning apparatus suppresses an increase in power consumption associated with a reduction in start-stop frequency of a compressor. The air conditioning apparatus includes an outdoor unit equipped with a compressor and a plurality of indoor units connected with the outdoor unit and has a control device that performs thermo-off and thermo-on control such that a suction air temperature of the indoor unit falls within a predetermined temperature range with a set temperature defined as a reference. The control device detects the suction air temperatures of the indoor units, and, in a case where a sum total of air conditioning capacities of the indoor units, the suction air temperatures of which are between the set temperature and the thermo-off temperature, is at least a predetermined value, makes at least one indoor unit, the suction air temperatures of which are between the set temperature and the thermo-off temperature, forcedly thermo-off.

Abstract: In the control device 12 of the indoor unit 11, a plurality of communication means 14a to 14c having different communication speeds; communication speed recognizing means 18 for recognizing whether or not a communication line 15 from an outdoor unit 10 is connected to any of the communication means, from the communication speed of the control information signal; and communication means confirmation means 18 for confirming the communication means that performs the following communication based on the recognized communication speed, are provided. According to this, it is possible to recognize the communication speed of an input signal without providing a manual changeover switch. Therefore, it is possible to solve at least one or more of the problems that the installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that the product prices increase.

Abstract: An air conditioner capable of detecting resonance of a casing of an outdoor or indoor unit of an air conditioner at a low cost with high accuracy is provided. An outdoor unit of the air conditioner includes: a propeller fan that blows air to a heat exchanger; a fan motor that drives the propeller fan; a current detector that detects a current value of the fan motor; a phase detector that detects the magnetic pole position of the fan motor; a fan rotation speed detector that detects the rotation speed of the fan motor; a pulsation detector that detects pulsation of the current value; and a resonance determiner that determines resonance of a system of a casing of the outdoor unit having the fan motor. If the resonance determiner determines resonance, a controller executes resonance avoidance control for increasing or decreasing the fan rotation speed by a predetermined rotation speed.

Abstract: The present disclosure provides an indoor unit of an air conditioner includes a housing, a centrifugal fan arranged inside the housing, and a heat exchanger arranged so as to surround the centrifugal fan, in which the heat exchanger includes an area cut in a direction of rotation of the centrifugal fan. A current plate provided at a final portion of the heat exchanger in the direction of the rotation of the centrifugal fan includes a first face which is extended in a height direction of the heat exchanger and blocks an air flow produced between the centrifugal fan and the heat exchanger and a second face protruded from the first face in a direction opposite the air flow. The indoor unit has an advantageous effect to suppress an inflow of air to a space where the heat exchanger is cut in the indoor unit to reduce the power consumption.

Abstract: An air conditioner which includes a compressor, an outdoor heat exchanger, an outdoor expansion valve, and an indoor heat exchanger that have been successively connected by a pipeline, and in which a hydrofluoroolefin-containing refrigerant is to be used, the air conditioner being characterized in that an oxygen adsorption device in which a synthetic zeolite is used as an adsorbent has been disposed somewhere in the pipeline, the synthetic zeolite having a pore diameter which is larger than the size of the oxygen molecule but smaller than the size of the hydrofluoroolefin molecule.

Abstract: In a permanent magnet electric motor, a plurality of projections are formed at least partially along an axial direction in the magnet insertion openings, the projection positioning both edges of the permanent magnet in the circumferential direction so that vacant spaces are defined at each sides of the permanent magnet in the circumferential direction; a plurality of slits arranged along the circumferential direction are provided in regions, the region being positioned radially outward from the permanent magnet and being sandwiched at the edges of the permanent magnet in the circumferential direction by the projections; and the shortest distance between the slit and the magnet insertion opening is set to be greater than the shortest distance between the slit and an outer circumferential surface of the rotor core.

Abstract: A scroll compressor includes a fixed scroll, an orbiting scroll, a suction section, a discharge section, and an electric motor. A sliding surface of a scroll is formed outside a wrap with a depression section depressed with respect to a sliding surface and a flange section elevated with respect to the depression section. The flange section is a remaining region in a protruding region disposed outside a referential perfect circle, the remaining region being other than a region continuing to an end of an involute curve of a scroll formed with the flange section, the referential perfect circle having a radius set to a distance between the center of the scroll formed with the flange section and the end of the involute curve. The scroll compressor enhances reduction of the sliding loss with a simple structure and reduction of the refrigerant leakage loss in the entire compression chambers.

Abstract: A scroll compressor has a sealed container inside which a working fluid is sealed; a frame fixed inside the sealed container; a fixed scroll provided with a fixed-side spiral body formed in a spiral shape on a fixed-side base plate fixed inside the sealed container; and a revolving scroll in which a revolving-side spiral body meshing with the fixed-side spiral body is provided on a revolving-side base plate. The frame includes a first welded point at which the frame is fixed by welding to the sealed container, and a revolving-scroll-receiving surface supports a bottom surface of the revolving-side base plate opposite to a surface thereof on which the revolving-side spiral body is provided. A frame outer peripheral groove provided in an outer periphery of the frame faces an inner periphery of the sealed container between the revolving-scroll-receiving surface and the first welded point.

Abstract: The present invention is intended to provide a general-purpose display device that is able to display on a display unit easily operating information required for assessing a test operation state, and an application program to be executed by the display device. Accordingly, in this display device which displays on the display unit the operating information of an air conditioner in which an outdoor unit provided with an outdoor heat exchanger and an indoor unit provided with an indoor heat exchanger are connected by a refrigerant pipe and a refrigerant is circulated by a compressor, a control unit of the display device controls the display unit so that time information is displayed horizontally and a first operating information display area and a second operating information display area for displaying first operating information and second operating information, respectively, corresponding to the time information are displayed vertically side by side.

Abstract: It is an object to obtain an air conditioner capable of suppressing rise of compressor discharge temperature and individually controlling cooling capacity of a plurality of respective indoor units. For this purpose, the air conditioner is a multi-room air conditioner, in which a refrigeration cycle is formed by connecting an outdoor unit 100 having an outdoor heat exchanger to the plurality of indoor units 200 and 300 having indoor heat exchangers 201 and 301 and indoor expansion mechanisms 203 and 303 using a liquid pipe 121 and a gas pipe 122. Further, as refrigerant circulating through the refrigeration cycle, R32 or mixed refrigerant containing 70 mass % or higher percent of R32 is used. Further, a temperature difference detection device to detect an air temperature difference between inlet-side air and outlet-side air in the respective indoor heat exchangers of the respective indoor units is provided.

Abstract: The air conditioner has: an outdoor heat exchanger that exchanges heat between the air and a refrigerant flowing in the interior of this heat exchanger; an outdoor fan that blows air into the outdoor heat exchanger; an outdoor fan motor that rotationally drives the outdoor fan; an outdoor fan inverter that supplies a desired current to the outdoor fan motor; a current detector that detects the current flowing in the outdoor fan motor; and a control unit that controls the outdoor fan inverter such that the rotational frequency of the outdoor fan motor reaches a target rotational frequency. The control unit starts a defrosting operation of the outdoor heat exchanger on the basis of a detection value from the current detector during the heating operation.

Abstract: A motor drive that enables the elimination of distortion of a motor current caused by direct current voltage ripples with the use of a smoothing capacitor having a small capacity and refrigeration equipment. A motor drive includes a rectifier circuit, a smoothing capacitor, voltage detector, an inverter circuit, current sensor, and a controller configured to control the inverter circuit. The controller has a voltage controller configured to generate a voltage command value used for controlling the motor, a ripple frequency arithmetic unit configured to operate a ripple frequency included in the direct current voltage signal, and a harmonic suppressor configured to process a signal based on the direct current signal using an S controller having a gain near the ripple frequency and output a corrected amount. The inverter circuit is controlled based on a signal that the voltage command value is corrected using the corrected amount.