Abstract: A rotary compressor (100A) includes a closed casing (1), a compression mechanism (48), a lower end-face plate (34), and a communication hole (50). An oil reservoir (12) is formed at the bottom of the closed casing (1). The lower end-face plate (34) divides the oil reservoir (12) into a plurality of sections (12a) and (12b) in the vertical direction. The plurality of sections of the oil reservoir (12) communicate with each other through the communication hole (50). The communication hole (50) is located on the same side as a discharge port (8b) of the compression mechanism (48) with respect to a reference plane (H1).

Abstract: There may be a case where, by simply coupling the first compressor (expander compressor unit) and the second compressor with an oil-equalizing pipe, the first compressor is not lubricated sufficiently, thereby decreasing reliability. The volumetric capacity (V1) of the first available oil space (130) of the first compressor (101) is set larger than the volumetric capacity (V2) of the second available oil space (140) of the second compressor (102). With this configuration, even if the oil level (S1) of the first oil sump (13) decreases in transition to a state of steady operation, it is possible to maintain a sufficient amount of oil in the first compressor (101), and thus high reliability as a fluid machine can be achieved.

Abstract: A fluid machine (101) includes a first compressor (107) and a second compressor (108). The first compressor (107) has a first closed casing (111), a first compression mechanism (102a), an expansion mechanism (104), and a shaft (113). A first oil reservoir (112) is formed in the first closed casing (111). The second compressor (108) has a second closed casing (125) and a second compression mechanism (102b). A second oil reservoir (126) is formed at a bottom portion in the second closed casing (125). The first closed casing (111) and the second closed casing (125) are connected to each other by an oil passage (109) so that a lubricating oil can flow between the first oil reservoir (112) and the second oil reservoir (126). An opening (109a) of the oil passage (109) on a side of the first closed casing (111) is located above the expansion mechanism (104) with respect to the vertical direction.

Abstract: A refrigeration cycle apparatus 100 is provided with a refrigerant circuit 106, an injection flow passage 111, and a high-pressure supply passage 130. The refrigerant circuit 106 includes a low-pressure stage compressor 105, a high-pressure stage compressor 101, a heat radiator 102, an expander 103, a gas-liquid separator 108, and an evaporator 104. The expander 103 and the low-pressure stage compressor 105 are coupled by a power-recovery shaft 107. The refrigeration cycle apparatus 100 is further provided with a flow passage-switching mechanism that selectively connects one of the evaporator 104 and the high-pressure supply passage 130 to the low-pressure stage compressor 105. The flow passage-switching mechanism, for example, is constituted by an on-off valve 131 and a check valve 132.

Abstract: An expander-compressor unit (200) includes a closed casing (1), a compression mechanism (2) disposed at an upper position in the closed casing (1), an expansion mechanism (3) disposed at a lower position in the closed casing (1), a shaft (5) coupling the compression mechanism (2) to the expansion mechanism (3), and an oil pump (6) disposed between the compression mechanism (2) and the expansion mechanism (3). The oil pump (6) supplies the oil held in an oil reservoir (25) to the compression mechanism (2) via a suction passage. A strainer (65) is provided to the suction passage so that the oil to be drawn into the oil pump (6) passes through the strainer.

Abstract: A fluid machine (10) includes a closed casing (11) in which an oil reservoir (16) for holding oil is formed in a bottom part.

Abstract: An expander-compressor unit (200) includes a closed casing (1), a compression mechanism (2), an expansion mechanism (3), a shaft (5), and an oil pump (6). The shaft (5) includes an upper shaft (5s) provided with an upper eccentric portion (5a) for the compression mechanism (2), and a lower shaft (5t) provided with lower eccentric portions (5d and 5c) for the expansion mechanism (3) and an intermediate eccentric portion (5e) for the oil pump (6). The expansion mechanism (3) has an upper bearing member (45) for supporting a supported portion (5f) of the lower shaft (5t) located immediately above the lower eccentric portion (5d). The intermediate eccentric portion (5e) has a diameter equal to or less than that of the supported portion (5f).

Abstract: A fluid machine (8A) includes an expander (4) having an expander suction port (4a) and an expander discharge port (4b), a compressor (6) having a compressor suction port (6a) and a compressor discharge port (6b), and a shaft (81) coupling the expander (4) to the compressor (6). The expander suction port (4a) and the compressor suction port (4a) are opened and closed as the shaft (81) rotates. The expander suction port (4a) is opened during a period of time when the compressor suction port (6a) is closed, and the compressor suction port (6a) is opened and maintained out of communication with the compressor discharge port (6b) during a period of time when the expander suction port (4a) is closed.

Abstract: An expander-compressor unit (200A) includes a closed casing (1), a compression mechanism (2), an expansion mechanism (3), a shaft (5), and an oil pump (6). The shaft (5) couples the compression mechanism (2) to the expansion mechanism (3) so that power recovered by the expansion mechanism (3) is transferred to the compression mechanism (2). The oil pump (6) is disposed between the compression mechanism (2) and the expansion mechanism (3), and supplies an oil held in an oil reservoir (25) to the compression mechanism (2). An oil supply passage (29) is formed in the shaft (5) so that the oil discharged from the oil pump (6) can be supplied to the compression mechanism (2). A lower end (29e) of the oil supply passage (29) is located below an inlet (29p) of the oil supply passage (29) formed in an outer circumferential surface of the shaft (5).

Abstract: The expander-compressor unit 70 includes the closed casing 1, the expansion mechanism 4 disposed in the closed casing 1 so that a surrounding space thereof is filled with the oil, the compression mechanism 2 disposed in the closed casing 1 so as to be positioned higher than the oil level, the shaft 5 for coupling the compression mechanism and the expansion mechanism 4 to each other, and the oil flow suppressing member 50 disposed in the surrounding space of the expansion mechanism 4 so that the space 55a filled with the oil is formed between the expansion mechanism 4 and the oil flow suppressing member 50. Thereby the flow of the oil filling the inner reserving space 55a is suppressed, and thus, heat transfer from the high temperature oil to the low temperature expansion mechanism can be reduced.

Abstract: A lap (201) of an orbiting scroll (21) and a lap (202) of a stationary scroll (22) are meshed with each other to form an inner wall side expansion chamber (203a) on the side of a lap inner wall (201a) of the orbiting scroll (21) and an outer wall side expansion chamber (203b) on the side of a lap outer wall (201a) of the orbiting scroll (21). The volumetric capacity of the inner wall side expansion chamber (203a) and that of the outer wall side expansion chamber (203b) are equal to each other when suction is completed, and different from each other when discharge starts, and their expansion ratios are different from each other.

Abstract: A rotary expander includes: a cylinder (61); a piston (62) disposed inside the cylinder (61); closing members disposed with the cylinder (61) being sandwiched therebetween; and an injection passage for introducing further a working fluid in the expansion process of the working fluid. An introduction outlet (65c) of the injection passage leading to the working chamber (69) is provided at a position located inwardly away from the inner circumferential surface (61b) of the cylinder (61), on one of the closing members, in such a manner that the injection passage and the discharge passage are not communicated with each other.

Abstract: An oil supply passage (68) is formed inside a rotating shaft (56) of a compression mechanism (21). An oil supply passage (38) is formed inside a rotating shaft (36) of an expansion mechanism (22). A boss portion (81) is provided at a lower end of the rotating shaft (56). A shaft portion (82) that is engaged in the boss portion (81) is provided at an upper end of the rotating shaft (36). The circumference of a coupling part (80), which includes the boss portion (81) and the shaft portion (82) is covered by an upper bearing (42) of the expansion mechanism (22). The upper bearing (42) supports both the rotating shaft (36) and the rotating shaft (56).

Abstract: An expander-integrated compressor (5A) has a compression mechanism (21) for compressing a refrigerant and an expansion mechanism (22) for expanding the refrigerant. The compression mechanism (21) is located above the expansion mechanism (22) inside a closed casing (10) and shares a rotating shaft (36) with the expansion mechanism (22). An oil pump (37) is provided at the lower end of the rotating shaft (36). The oil pump (37) is immersed in oil in an oil reservoir (15). Usually, the oil is placed in the oil reservoir (15) in such a manner that the oil level (OL) is located above a lower end portion (34e) of a vane (34a) of a first expansion section (30a). More preferably, the oil is placed in such a manner that the expansion mechanism (22) is immersed in the oil. An oil supply passage (38) for guiding the oil to the compression mechanism (21) is formed inside the rotating shaft (36). A suction port (37a) of the oil pump (37) is provided below the lower end portion (34e) of the vane (34a).

Abstract: A refrigeration cycle apparatus (100) includes a first compressor (101), a second compressor (102), a radiator (4), an evaporator (6), and a pipe branching portion (30). The first compressor (101) has a first compression mechanism (1) and an expansion mechanism (5). The second compressor (102) has a second compression mechanism (2). The pipe branching portion (30) serves as a flow passage for introducing a refrigerant from the evaporator (6) to the first compression mechanism (1) and the second compression mechanism (2), respectively. The pipe branching portion (30) includes an inlet pipe (31) for receiving the refrigerant from the evaporator (6), a first branch outlet pipe (32) for introducing the refrigerant flowing into the inlet pipe (31) to the first compression mechanism (1), and a second branch outlet pipe (33) for introducing the refrigerant flowing into the inlet pipe (31) to the second compression mechanism (2).

Abstract: A refrigeration cycle apparatus includes an expander-compressor unit (1) having a first motor (12), a second compressor (2) having a second motor (22), and a controller (7). The controller (7) determines the target rotational frequency F1 of the first motor (12) and the target rotational frequency F2 of the second motor (22) for a start-up operation, and determines whether the opening X of an injection valve (61) should be in a fully opened state or in a fully closed state during the start-up operation, based on an outside air temperature and other factors. Then, the controller (7) performs the start-up operation by controlling the rotational frequencies f1 and f2 of the first motor and the second motor to be the determined target rotational frequencies F1 and F2 while maintaining the opening X of the injection valve in the fully opened state or in the fully closed state.

Abstract: A refrigeration cycle apparatus 1 includes a refrigerant circuit in which a refrigerant circulates. The refrigerant circuit is formed by connecting in sequence a compressor 2 for compressing the refrigerant, a radiator 3 for allowing the refrigerant compressed by compressor 2 to radiate heat, a fluid pressure motor 4 as a power recovery means, and an evaporator 5 for allowing the refrigerant discharged by the fluid pressure motor 4 to evaporate. The fluid pressure motor 4 performs a process for drawing the refrigerant and a process for discharging the refrigerant. These processes are performed substantially continuously.

Abstract: A multi-stage rotary-type fluid machine may be configured as what is called a two-stage rotary expander, in which a refrigerant expands in an expansion chamber having a first discharge side space (115b) of a first cylinder (105), a second suction side space (116a) of a second cylinder (106), and a communication hole (104a) for allowing communication between the two spaces (115b, 116a). The first cylinder (105) and the second cylinder (106) are partitioned by an intermediate plate (104). The communication hole (104a) is formed so as to penetrate through the intermediate plate (104). The opening shape and location of the communication hole (104a) are set so that direct blow-through of the refrigerant from a suction port (105b) to a discharge port (106b) cannot occur at any rotation angle of a shaft (103).

Abstract: A refrigeration cycle apparatus 100 is provided with a working fluid circuit 106 and a first bypass passage 112. The working fluid circuit 106 is formed of a first compressor 101, a heat radiator 102, an expander 103, an evaporator 104, a second compressor 105, and flow passages 106a to 106e connecting these components in this order. The expander 103 and the second compressor 105 are coupled to each other by a power-recovery shaft 107 so that the second compressor 105 is driven by the power recovered by the expander 103. The first bypass passage 112 communicates between a portion from the discharge port of the first compressor 101 to the suction port of the expander 103 in the working fluid circuit 106 and a portion from the outlet of the evaporator 104 to the suction port of the second compressor 105 in the working fluid circuit 106, at the time of activation of the refrigeration cycle apparatus 100.

Abstract: A refrigeration cycle apparatus 100 includes a low-pressure compressor 113, a high-pressure compressor 101, a radiator 103, a gas-liquid separator 107, an expansion valve 109, an expander 105 and an evaporator 111. The low-pressure compressor 113 and the expander 105 are coupled by a shaft 116, and the low-pressure compressor 113 is driven using power recovered by the expander 105 from a refrigerant. The low-pressure compressor 113 and the high-pressure compressor 101 are serially connected by an intermediate-pressure flow path 114. The gas-liquid separator 107 and the intermediate-pressure flow path 114 are connected by the reciprocating flow path 115. The reciprocating flow path 115 is configured to allow the refrigerant to circulate bidirectionally. It is possible to regulate the refrigerant flow rate in the reciprocating flow path 115 by controlling the opening degree of the expansion valve 109.