Abstract: A centrifugal fan includes a back plate, a shroud, and multiple blades. The multiple blades include first to third blades. The first to third blades include first to third leading edge parts and first to third trailing edge parts. First to third lengths are the length from the first to third leading edge parts to the first to third trailing edge parts. The second length is greater than the first length. The third length is greater than the second length. The numbers of the first to third blades are equal. The total number of the multiple blades is a multiple of 3, and is not less than 6. The first to third blades are arranged in a rotation direction in the order of the first blade, the second blade, and the third blade.

Abstract: An electric motor controller of an embodiment includes: a PWM signal generation unit that generates three-phase PWM signal patterns to follow a magnetic pole position of the motor; a current detection unit that detects a phase current of the motor; a current change amount detection unit that outputs a difference between current values detected twice for each of two phases, as current change amounts; and a magnetic pole position estimation unit that estimates a magnetic pole position of the motor based on the current change amounts. The PWM signal generation unit uses a triangular carrier wave, generates three-phase PWM signal patterns to allow the current detection unit to detect current of each two phase twice at timing of four points within a carrier wave period of the PWM signal, shifts a maximum phase in one direction of an advancing or delay side, and oppositely shifts a medium phase.

Abstract: Proposed are a refrigeration cycle apparatus and a leakage inspection method for refrigerant piping of a refrigeration cycle apparatus, in both of which leakage inspection of joints of the refrigerant piping can be readily performed regardless of where the joints of the refrigerant piping are provided, including a space being hard-to approach, inaccessible, and extremely narrow. A refrigeration cycle apparatus includes: a plurality of pipe materials; refrigerant piping including a joint that joins the pipe materials by brazing or welding; and a piping cover that covers at least part of the refrigerant piping including the joint and has a leakage inspection port that allows a gas to flow out from the inside to the outside.

Abstract: A refrigeration cycle apparatus includes an air conditioner, sensors, and processing circuitry. The processing circuitry determines a predicted opening of the electronic expansion valve of the air conditioner based on outputs of the sensors and an operation frequency of the compressor, assuming normal operation of the air conditioner. The processing circuitry calculates a prediction error by subtracting a measured opening of the electronic expansion valve from the predicted opening. The processing circuitry calculates multiple prediction errors in advance, calculates an offset value as an average of the multiple prediction error, and outputs a corrected prediction error by subtracting the offset value from the current prediction error. The processing circuitry detects a refrigerant leak of the air conditioner based on the corrected prediction error.

Abstract: An axial fan includes: an impeller including a rotating part, and a blade part connected to the rotating part; a bellmouth including a flat part orthogonal to an extension direction of a rotation axis of the rotating part; a rising part rising from the flat part; and an opening along which the rising part extends, the impeller being located in the opening, the rising part surrounding the impeller, the bellmouth including a plurality of grooves located at a surface of the bellmouth, the surface of the bellmouth being connected to an inner surface of the rising part, the inner surface of the rising part facing the blade part of the impeller, the plurality of grooves being located in at least a corner portion connecting the flat part and the rising part, the plurality of grooves extending in a direction crossing the flat part.

Abstract: According to one embodiment, a rotary compressor includes a compression mechanism unit. When H is the length of a middle shaft part, Hp is the length of a bearing hole, Dp is the inner diameter of the bearing hole, Dc is the outer diameter of a crank part, Dm is the outer diameter of the middle journal part, C1 is the axial length of a first chamfered part provided to a middle shaft part-side end edge of the crank part, C2 is the axial length of a second chamfered part, C3 is the axial length of a third chamfered part, and C4 is the axial length of a fourth chamfered part, Dp is larger than Dc and Dm, and the relationships of [Equation 1] H?Hp, [Equation 2] H>Hp?C1?C2??{square root over ((Dp2?Dc2))}, and [Equation 3] H>Hp?C3?C4??{square root over ((Dp2?Dm2))} are all satisfied.

Abstract: A compressor of an embodiment includes a compression mechanism part that compresses a refrigerant in a sealed container. The compression mechanism part includes Cr and includes a first member and a second member which slidingly move relative to each other. The first member has a chromium layer and a nitride layer formed on a base member surface in this order. The nitride layer includes CrN and TiN. Carbide is deposited on a surface of the second member.

Abstract: A state evaluation system includes a sensor, a filter, a signal processor, and an evaluator. The sensor detects elastic waves which are generated from industrial equipment in operation. The filter can pass elastic waves having frequency characteristics based on abrasion which is generated in the industrial equipment. The signal processor extracts a plurality of feature values using the elastic waves passing through the filter. The evaluator evaluates an abnormality of the industrial equipment on the basis of a combination of the extracted plurality of feature values.

Abstract: A compressor of an embodiment includes three suction pipes. A first center of a first suction pipe, a second center of a second suction pipe, and a third center of a third suction pipe are positioned at vertices of a triangle. A first distance between the first center and a center of a compressor main body is smaller than a second distance between the second center and the center of the compressor main body and a third distance between the third center and the center of the compressor main body. The first suction pipe is connected to a first suction port on an uppermost side. A second virtual plane on which a central axis of a main curved pipe part of the second suction pipe is disposed and a third virtual plane on which a central axis of a main curved pipe part of the third suction pipe is disposed are inclined to opposite sides from each other with respect to a first virtual plane on which a central axis of a main curved pipe part of the first suction pipe is disposed.

Abstract: A communication system includes a master unit; and a plurality of slave units including a slave unit to which a termination resistance is set, the plurality of slave units connected to the master unit via a communication line. In the communication system, the master unit includes a master communication control unit that normally sets a communication rate of communication performed with the plurality of slave units to a high baud rate, switches the high baud rate to a low baud rate after detecting that communication with the slave unit to which the termination resistance is set is disabled, transmits an instruction for switching the low baud rate to the high baud rate to the plurality of slave units after detecting that the communication with the slave unit to which the termination resistance is set is restored, and switches setting of the master unit itself to the high baud rate.

Abstract: An air conditioning system of the embodiment includes a first indoor unit and a second indoor unit. The first indoor unit controls a temperature of the inside of a space by controlling blowing of warm air from an upper part of the space to the inside of the space. The second indoor unit controls blowing of warm air from under a floor of the space to the inside of the space on the basis of a temperature in a lower part of the space.

Abstract: A detection device is connected to a plurality of communication devices by a communication line. The detection device has a reception unit, a measurement unit, and a detection unit. The reception unit receives signals with prescribed pulse widths transmitted from the plurality of communication devices, respectively. The measurement unit measures the pulse widths of the signals received by the reception unit. The detection unit is configured to detect the communication device disposed near a terminal end of the communication line as a terminal-end communication device on the basis of the plurality of pulse widths measured by the measurement unit.

Abstract: A communication system includes a master unit; and a plurality of slave units including a slave unit to which a termination resistance is set, the plurality of slave units connected to the master unit via a communication line. In the communication system, the master unit includes a master communication control unit that normally sets a communication rate of communication performed with the plurality of slave units to a high baud rate, switches the high baud rate to a low baud rate after detecting that communication with the slave unit to which the termination resistance is set is disabled, transmits an instruction for switching the low baud rate to the high baud rate to the plurality of slave units after detecting that the communication with the slave unit to which the termination resistance is set is restored, and switches setting of the master unit itself to the high baud rate.

Abstract: According to one embodiment, an information management system that autonomously controls a manufacturing process and equipment by diversifying a feedback loop in a CPS is provided. The embodiment is applied to an information management system that autonomously controls a manufacturing process and a service. A loop connection section connects a feedback loop of the cyber-physical system. An information acquisition section acquires specific information necessary for the manufacturing process and the service from the feedback loop. An information analytics section analyzes the specific information. An autonomous operation control section autonomously performs the operation control based on an analytics result from the information analytics section.

Abstract: An air conditioner management device that has a plurality of air conditioners as management targets, includes: a displayed-information generation unit that, as for the plurality of air conditioners, generates display information on a summary screen including mode-specific working unit number information indicating the number of air conditioners currently in an ON state in each set working mode and mode-specific stopped unit number information indicating the number of air conditioners currently in an OFF state in each set working mode; and a display unit that displays the display information generated by the displayed-information generation unit.

Abstract: According to one embodiment, a rotary compressor includes a compression mechanism unit and an electric motor. The compression mechanism unit includes a first bearing, a second bearing, first to third refrigerant compression units, a second intermediate partitioning panel, and a rotation shaft. The compression mechanism unit is fixed to the sealed container by a pair of fixing units which are provided at two locations spaced apart from each other in the axial direction of the rotation shaft, and the center of gravity of a structure comprising the compression mechanism unit and the rotor of the electric motor is positioned between the pair of fixing units.

Abstract: To achieve both improving operability of stop valves and downsizing an outdoor unit, the outdoor unit for an air-conditioner includes a valve fixing frame provided on the base frame, and a plurality of stop valves fixed to the valve fixing frame. A beam of the valve fixing frame includes a first notch opened upward, in which a first stop valve is disposed therein, and a second notch opened downward, in which a second stop valve is disposed therein. The first stop valve and the second stop valve are different in installation height in a vertical direction with reference to the installation surface.

Abstract: An air conditioner that has a controller and is such that an outdoor unit, which is provided with a compressor, an outdoor heat exchanger, an accumulator, and a supercooling heat exchanger, and indoor units provided with indoor heat exchangers, are connected to each other by connecting piping to constitute a refrigerant circuit. The bottom of the accumulator is connected to an intake side of the compressor via return bypass piping that is provided with an electromagnetic valve. The cooling source for the supercooling heat exchanger is a supercooling bypass circuit provided with a supercooling expansion valve; and when the amount of refrigerant during heating operation is determined to be excessive, the controller performs a control so as to fully close the electromagnetic valve of the return bypass piping and to gradually increase the opening degree of the supercooling expansion valve of the supercooling bypass circuit from a fully closed state.