Abstract: A compressor includes: a shell forming an outer portion thereof and having lower part in which an oil pan is formed to store oil; a motor provided in the shell; a compression unit provided in the shell to compress a working gas when being driven by the motor; a frame fixed to the shell and supporting the compression unit; a shaft supported by the frame, connecting the motor and the compression unit, provided to transmit a turning force of the motor to the compression unit, and including an oil passage; and an oil pump provided at lower part of the shaft to draw oil from the pan and supply the oil into the oil passage. The pump includes a bypass valve that is opened, when a pressure of oil flowing in the oil passage is higher than a threshold pressure, to return part of the oil to the pan.

Abstract: A refrigeration cycle apparatus includes: a refrigeration cycle circuit in which a compressor, a condenser, a first expansion valve, and an evaporator are connected by refrigerant pipes; an injection pipe having a refrigerant inflow side end and a refrigerant outflow side end, the refrigerant inflow side being connected between the condenser and the first expansion valve, the refrigerant outflow side end being connected to a suction side of the compressor; a second expansion valve provided at the injection pipe; and a controller that controls a rotation speed of the compressor and an opening degree of the second expansion valve. In the case of reducing a heat-exchange capability of the evaporator when the rotation speed of the compressor is a specified rotation speed, the controller performs a low load operation during which refrigeration is caused to flow through the injection pipe.

Abstract: A scroll compressor includes: a shell; a compression mechanism unit accommodated in the shell and defining a compression chamber, the compression mechanism unit having a discharge port through which a discharge chamber and the compression chamber communicate with one another; a discharge valve mechanism that opens and closes the discharge port. The discharge valve mechanism includes a valve seat provided on an outlet portion of the discharge port and a valve and closes the valve seat when sitting on the valve seat. The valve seat includes an annular portion serving as an edge of an opening of the outlet portion and a valve supporting portion that is provided in a region surrounded by the inner circumference of the annular portion and divides the opening of the outlet portion into plural valve seat holes. The valve is in contact with at least a portion of the valve supporting portion and with the annular portion, when sitting on the valve seat.

Abstract: A scroll compressor includes: a shell forming an outer case, a fixed scroll and an orbiting scroll stored in the shell, a frame holding the orbiting scroll, a thrust plate between the orbiting scroll and the frame, and a thrust oil return pipe fixed to the frame. The shell forms an oil reservoir in which lubricating oil is reserved. The orbiting scroll and fixed scroll form a compression chamber. Lubricating oil flows through the thrust oil return pipe to return to the oil reservoir. A hole portion on the thrust plate passes from a first surface portion that slidably contacts the orbiting scroll to a second surface portion facing the frame. The thrust oil return pipe is inserted into the hole portion and fits in the thrust plate.

Abstract: A compressor system includes a compressor including a bearing supporting a rotating shaft; a sensor configured to measure an index value correlated with a movement of the rotating shaft being made while the compressor is in operation; and a wear-detecting unit configured to detect a degree of wear of the bearing based on a measured value obtained by the sensor. The bearing is a plain bearing, and has a plurality of air gaps arranged at intervals in a circumferential direction such that wear of the bearing changes a positional relationship between an inner circumferential surface of the bearing and the plurality of air gaps and eventually changes a shape of the inner circumferential surface thereof. The wear-detecting unit detects the degree of wear of the bearing based on a change in the measured value caused by a change in the shape of the inner circumferential surface of the bearing.

Abstract: An orbital scroll wrap and a fixed scroll wrap of a scroll compressor include respective scroll start portions each having a bulbous shape defined by connecting an involute start point of an outer-surface involute curve and an involute start point of an inner-surface involute curve to each other with a plurality of arcs. At least one of the scroll start portions has a tiered shape wherein an n number (where n?2) of tiers each having the bulbous shape are stacked in an axial direction of a main shaft. Letting involute-start-point angles of the outer-surface involute curves in respective tiers of the scroll start portion having the tiered shape be ?os(1), ?os(2), ?os(3), . . . , and ?os(n) in order from tip to base of the scroll start portion, the following is satisfied: ?os(1)>?os(2)>?os(3)> . . . >?os(n); and 0.3?<?os(1)-?os(n)<0.7?.

Abstract: A compressor includes: a shell forming an outer portion thereof and having lower part in which an oil pan is formed to store oil; a motor provided in the shell; a compression unit provided in the shell to compress a working gas when being driven by the motor; a frame fixed to the shell and supporting the compression unit; a shaft supported by the frame, connecting the motor and the compression unit, provided to transmit a turning force of the motor to the compression unit, and including an oil passage; and an oil pump provided at lower part of the shaft to draw oil from the pan and supply the oil into the oil passage. The pump includes a bypass valve that is opened, when a pressure of oil flowing in the oil passage is higher than a threshold pressure, to return part of the oil to the pan.

Abstract: A compressor includes a compression mechanism that compresses refrigerant; a main shaft that transmits a rotational driving force to the compression mechanism; a balance weight provided below the compression mechanism and integrated with the main shaft, the balance weight having a cylindrical outer peripheral surface centered at the main shaft; and an oil sump portion provided below the balance weight and stores lubricating oil to be supplied to the compression mechanism. The balance weight has an annular oil-receiving recessed portion in an upper surface, the oil-receiving recessed portion being centered at the main shaft and integrated with the balance weight. The balance weight has a hollow portion in a lower surface, the hollow portion extending in part of the lower surface in a peripheral direction around the main shaft and being integrated with the balance weight. The oil-receiving recessed portion communicates with at least part of the hollow portion.

Abstract: A scroll compressor includes: a shell forming an outer case, the shell forming an oil reservoir in which lubricating oil is reserved; a fixed scroll stored in the shell; an orbiting scroll stored in the shell, the orbiting scroll forming a compression chamber together with the fixed scroll; a frame holding the orbiting scroll; a thrust plate disposed between the orbiting scroll and the frame; and a thrust oil return pipe fixed to the frame, the thrust oil return pipe being a pipe through which the lubricating oil flows to return to the oil reservoir, in which: a hole portion is formed on the thrust plate, the hole portion passing from a first surface portion to a second surface portion, the first surface portion slidably contacting with the orbiting scroll, the second surface portion facing the frame; and the thrust oil return pipe is inserted into the hole portion and is fit in the thrust plate, and an upper end portion of the thrust oil return pipe does not protrude from the first surface portion of the thr

Abstract: A refrigeration cycle apparatus includes: a refrigeration cycle circuit in which a compressor, a condenser, a first expansion valve, and an evaporator are connected by refrigerant pipes; an injection pipe having a refrigerant inflow side end and a refrigerant outflow side end, the refrigerant inflow side being connected between the condenser and the first expansion valve, the refrigerant outflow side end being connected to a suction side of the compressor; a second expansion valve provided at the injection pipe; and a controller that controls a rotation speed of the compressor and an opening degree of the second expansion valve. In the case of reducing a heat-exchange capability of the evaporator when the rotation speed of the compressor is a specified rotation speed, the controller performs a low load operation during which refrigeration is caused to flow through the injection pipe.

Abstract: A scroll compressor including an orbiting scroll and a fixed scroll. A compression chamber is formed by combining a fixed-scroll volute of the fixed scroll and an orbiting-scroll volute of the orbiting scroll. Each of sub-discharge ports of the fixed scroll brings any one of a first compression chamber and a second compression chamber of a compression chamber, the first compression chamber being defined by an inward-facing surface of the fixed-scroll volute and an outward-facing surface of the orbiting-scroll volute, the second compression chamber being defined by an outwardfacing surface of the fixed-scroll volute and an inward-facing surface of the orbiting scroll volute, and a discharge side into communication with each other.

Abstract: A scroll compressor includes a bush having a shaft part and a balance weight part. The balance weight part is secured to an outer periphery of the shaft part by shrink-fitting. The shaft part includes: a cylindrical body part; and a cylindrical coupling part which extends outward from an axial end portion of the body part, and to which the balance weight part is joined. The bush satisfies the following requirements: 1.2?D2/D1?1.6; and??(a) 1.0?[(D2?D3)/(D4?D2)]×E1/E2?3.5,??(b) where D1 is the outer diameter of the body part, D2 is the outer diameter of the coupling part, D3 is the inner diameter of the body part, D4 is the outer diameter of the balance weight part, E1 is the Young's modulus of the shaft part, and E2 is the Young's modulus of the balance weight part.

Abstract: A scroll compressor includes a crank shaft, an orbiting scroll, and a frame. The crank shaft has a lubricant channel. The orbiting scroll has an inner channel and a lubricant channel groove. The inner channel allows the lubricant supplied through the crank shaft to flow outward. The lubricant channel groove has an annular shape and allows the lubricant supplied through the inner channel to be supplied to the thrust surface. The lubricant channel groove is formed such that the lubricant channel groove stays within a region of the thrust surface while the orbiting scroll is orbiting.

Abstract: A scroll compressor includes a crank shaft 6, an orbiting scroll 32, and a second plug part 329. The crank shaft 6 has a lubricant channel 63 which allows lubricant 9 to flow therethrough. The orbiting scroll 32 is attached to the crank shaft 6 and has a second inner channel 327 that allows the lubricant supplied thereto through the crank shaft 6 to outwardly flow therethrough. The second plug part 329 serving as an adjustment part is provided in the second inner channel 327 of the orbiting scroll 32 and adjusts a flow amount of the lubricant 9 flowing through the second inner channel 327.

Abstract: A scroll compressor includes a fixed scroll and an orbiting scroll, which are made of materials having different strengths and which include respective scroll laps. The scroll lap of the fixed scroll and the orbiting scroll having a lower material strength has a thickness satisfying tl=2a?, where tl represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap of the fixed scroll and the orbiting scroll having a higher material strength has a thickness satisfying th=2a?, where th represents scroll lap thickness, a represents basic circle radius, and ? represents phase angle. The scroll lap thickness th of the fixed scroll and the orbiting scroll having the higher material strength is set to be less than the scroll lap thickness tl of the fixed scroll and the orbiting scroll having the lower material strength.

Abstract: A compressor includes a compression mechanism that compresses refrigerant; a main shaft that transmits a rotational driving force to the compression mechanism; a balance weight provided below the compression mechanism and integrated with the main shaft, the balance weight having a cylindrical outer peripheral surface centered at the main shaft; and an oil sump portion provided below the balance weight and stores lubricating oil to be supplied to the compression mechanism. The balance weight has an annular oil-receiving recessed portion in an upper surface, the oil-receiving recessed portion being centered at the main shaft and integrated with the balance weight. The balance weight has a hollow portion in a lower surface, the hollow portion extending in part of the lower surface in a peripheral direction around the main shaft and being integrated with the balance weight. The oil-receiving recessed portion communicates with at least part of the hollow portion.

Abstract: A fluid compressor includes a closed container having an inlet, a compression mechanism including a compression chamber in which fluid flowing into the closed container through the inlet is compressed, a discharge port through which the fluid compressed in the compression chamber is allowed to flow, a discharge valve opening and closing the discharge port, and a valve retainer limiting an amount of lift of the discharge valve. The discharge valve includes a curved portion whose shape is defined by one or more curvatures. When the discharge port is closed by the discharge valve, the valve retainer and the discharge valve are spaced apart from each other.

Abstract: A scroll compressor includes a crank shaft, an orbiting scroll, and a frame. The crank shaft has a lubricant channel allowing lubricant to flow through the lubricant channel. The orbiting scroll is attached to the crank shaft and includes a base plate that is discoidal. The frame has a thrust surface against which the orbiting scroll slides. The thrust surface has an annular shape and faces an outer circumferential region of one surface of the base plate of the orbiting scroll. The orbiting scroll has an inner channel and a lubricant channel groove. The inner channel allows the lubricant supplied through the crank shaft to flow outward. The lubricant channel groove has an annular shape in the outer circumferential region of the one surface of the base plate facing the thrust surface and allows the lubricant supplied through the inner channel to be supplied to the thrust surface.

Abstract: A scroll compressor including an orbiting scroll and a fixed scroll. A compression chamber is formed by combining a fixed-scroll volute of the fixed scroll and an orbiting-scroll volute of the orbiting scroll. Each of sub-discharge ports of the fixed scroll brings any one of a first compression chamber and a second compression chamber of a compression chamber, the first compression chamber being defined by an inward-facing surface of the fixed-scroll volute and an outward-facing surface of the orbiting-scroll volute, the second compression chamber being defined by an outwardfacing surface of the fixed-scroll volute and an inward-facing surface of the orbiting scroll volute, and a discharge side into communication with each other.

Abstract: A scroll compressor includes a bush having a shaft part and a balance weight part. The shaft part is disposed between an orbiting bearing that supports an orbiting scroll, and an eccentric pin of a crankshaft. The balance weight part is secured to the outer periphery of the shaft part by shrink-fitting. The shaft part includes: a cylindrical body part which is fitted into the orbiting bearing, and into which the eccentric pin of the crankshaft is inserted; and a cylindrical coupling part which extends outward from an axial end portion of the body part, and to which the balance weight part is joined. The bush satisfies the following requirements: 1.2?D2/D1?1.6, and??(a) 1.0?(D2?D3)/(D4?D2)×E1/E2?3.5,??(b) where D1 is the outer diameter of the body part, D2 is the outer diameter of the coupling part, D3 is the inner diameter of the body part, D4 is the outer diameter of the balance weight part, E1 is the Young's modulus of the shaft part, and E2 is the Young's modulus of the balance weight part.