Abstract: A heat exchanger includes a plurality of plate-shaped fins disposed at intervals, and a plurality of heat transfer tubes disposed to be inserted into through holes of the fins in a direction perpendicular to the fins. In each of the fins, a starting hole is formed between adjacent through holes, and the starting hole serves as a start point of bending of the fins and has a vertex portion at a bending portion of each fin which is close to an edge thereof. In each of the fins, a cut is made to connect the other edge of the fin and a side of the starting hole which is located opposite to the vertex portion of the starting hole. The above each fin is bent at the vertex portion of the starting hole, by opening the cut from the starting hole.

Abstract: A tripod type constant velocity universal joint includes an outer joint member having track grooves, a tripod member including trunnion journals, and spherical rollers each fitted in a rotatable manner about each of the trunnion journals through intermediation of a plurality of needle rollers. A corner portion is formed at a root portion of each of the trunnion journals so as to restrict movement of the plurality of needle rollers in the axial direction toward the root portion of each of the trunnion journals by interference between an end surface corner rounded portion of each of the plurality of needle rollers and the corner portion at the root portion.

Abstract: Provided is an air-conditioning apparatus configured so that a decrease in a refrigeration capacity can be suppressed without increasing the amount of refrigerant with which a refrigerant circuit is filled and that refrigerant can be suitably stored during a pump down operation. The air-conditioning apparatus includes a first on-off valve provided at a pipe between an expansion valve and a use side heat exchanger, a bypass branching from a pipe between the expansion valve and the first on-off valve and connected to a pipe at a suction-side of a compressor, and a refrigerant storage unit configured to store the refrigerant having passed through the bypass. In a pump down operation in which the compressor operates with the first on-off valve being in a closed state, the refrigerant having flowed out from the heat source side heat exchanger flows into the bypass, and then, is stored in the refrigerant storage unit.

Abstract: When a controller determines that a leakage of refrigerant occurs, the controller executes a control of rotating an air-sending fan at high rotation speed. After the control, the controller executes a control of stopping rotation of the air-sending fan or reducing a rotation speed of the air-sending fan in accordance with a result of detection by a first refrigerant sensor provided in a lower portion of a heat exchanger chamber. Thus, the air-sending fan is prevented from continuing the rotation at high rotation speed. Therefore, an indoor unit for an air-conditioning apparatus is excellent in safety and is capable of avoiding feeling of discomfort of a user due to the high-speed rotation of the air-sending fan.

Abstract: An air-conditioning apparatus can suppress occurrence of disproportionation (an autolytic reaction) when HFO1123 refrigerant or a refrigerant mixture containing HFO1123 is applied. The air-conditioning apparatus includes a controller controlling at least one of an operation frequency of a compressor, an opening degree of an expansion valve, and an air amount of a fan sending air to a heat-source-side heat exchanger so that a temperature and a pressure of the refrigerant discharged from the compressor do not exceed threshold values.

Abstract: An air-conditioning apparatus includes a time constant calculation unit that estimates a response time constant at a time when an opening degree of an expansion device is changed on the basis of specifications of a compressor that forms a refrigeration cycle of the air-conditioning apparatus, specifications of a load side heat exchanger, and an operating state quantity of the air-conditioning apparatus, a control constant calculation means that calculates at least one of a control gain of the opening degree of the expansion device and a control interval on the basis of a calculation result of the time constant calculation means, and a control constant change means that changes a control constant.

Abstract: An indoor unit of an air-conditioning apparatus includes a main body, the main body including a back case shaped like a box and provided with an open front face, and a front case joined to the front face of the back case, wherein on a bottom face of the front case, at a location away from a joining portion between the back case and the front case, a step is formed protruding downward.

Abstract: Provided is a tripod type constant velocity universal joint, including: an outer joint member having track grooves; a tripod member including trunnion journals; and spherical rollers each fitted in a rotatable manner about each of the trunnion journals through intermediation of a plurality of needle rollers, in which a corner portion is formed at a root portion of the each of the trunnion journals so as to restrict movement of each of the plurality of needle rollers in the axial direction toward the root portion of the each of the trunnion journals by interference between an end surface corner rounded portion of the each of the plurality of needle rollers and the corner portion at the root portion.

Abstract: An apparatus includes a refrigerant circuit in which a compressor that compresses a refrigerant, an indoor-side heat exchanger serving as a radiator that exchanges heat between the refrigerant and a heating target, an expansion valve that decompresses the refrigerant by opening-degree adjustment, and an outdoor-side heat exchanger serving as an evaporator that exchanges heat between a heat-exchange target and the refrigerant are connected by pipes. The apparatus includes: an outdoor air temperature sensor that detects a temperature of outdoor air serving as the heat-exchange target; a discharge-side temperature sensor that detects a discharge temperature of the refrigerant discharged by the compressor; and a controller that, when the controller determines that a rotation speed of the compressor is a maximum and the temperature of the heat-exchange target is lower than a preset temperature, controls an opening degree of the expansion valve by using the discharge temperature.

Abstract: In an axial flow fan according to the present invention, a plurality of blades rotate about a rotation axis of the blades to convey a fluid. In the axial flow fan, the plurality of blades each have a leading edge at a leading side in a rotational direction, a trailing edge at a trailing side in the rotational direction, and an outer peripheral edge connecting the leading edge and the trailing edge. The leading edge of one of the plurality of blades and the trailing edge of another blade adjacent to the leading edge of the blade in the rotational direction are connected by a plate-shaped connection portion. The plurality of blades each have at least one plate-shaped reinforcement rib extending from a periphery of the rotation axis toward the outer peripheral edge of the blade.

Abstract: When a controller determines that a leakage of refrigerant occurs, the controller executes a control of rotating an air-sending fan at high rotation speed. After the control, the controller executes a control of stopping rotation of the air-sending fan or reducing a rotation speed of the air-sending fan in accordance with a result of detection by a first refrigerant sensor provided in a lower portion of a heat exchanger chamber. Thus, the air-sending fan is prevented from continuing the rotation at high rotation speed. Therefore, an indoor unit for an air-conditioning apparatus is excellent in safety and is capable of avoiding feeling of discomfort of a user due to the high-speed rotation of the air-sending fan.

Abstract: In an indoor unit of an air-conditioning apparatus according to the present invention, an air inlet for room air is provided at a position lower than a height position of a drain pan. A partition plate is provided to partition a space below a height position of the drain pan in a housing. A pipe connecting portion connected to a refrigerant pipe of an outdoor unit is provided in one part of the partitioned space and a heat exchanger and a fan are placed in the other part of the partitioned space. At least one communicating path is formed in the partition plate to communicate the two parts of the partitioned space with each other.

Abstract: A pipe joint is connected with a connecting pipe, and includes a pipe joint body and a nut member. When the connecting pipe formed with a bead expanded in the radial direction is connected with this pipe joint, a male thread of the pipe joint body is engaged with a female thread of the nut member to hold the bead between a tapered face and a tapered face. In addition, the joined portion between the bead and the tapered face forms a first sealed portion, and a joined portion between the bead and the tapered face forms a second sealed portion. Still further, a tapered face of the pipe joint body is joined with the tapered face of the nut member to form a third sealed portion.

Abstract: A leading edge of a blade has a first curved portion provided with a leading-edge rearmost point, and a trailing edge of the blade has a second curved portion located on the inner circumferential side of the trailing edge and a third curved portion located on the outer circumferential side of the blade on the trailing edge. The third curved portion has a trailing-edge foremost point, and the second curved portion has a trailing-edge rearmost point. The trailing edge and a first concentric circle, which is one of concentric circles having as their center an axis of rotation and passes through the leading-edge rearmost point, intersect each other at a first intersection. The first intersection is located between the trailing-edge rearmost point and the trailing-edge foremost point.