Abstract: [Problem] To reduce imbalance among all movable components of a scroll compressor including a drive shaft and components fixed or connected to the drive shaft. In a scroll compressor 10, a shaft balancer 31 integrated with a drive shaft 30 includes a first weight 33 disposed on the opposite side from an eccentric pin 71 with respect to a center line CL0 of the drive shaft 30, and a bushing balancer 721 integrated with an eccentric bush 72 includes a second weight 723 disposed on the radially outer side of the eccentric bush 72 and on the opposite side from a center line CL1 of the eccentric pin 71 with respect to a center line CL2 of the eccentric bush 72. In a view from the axial direction of the drive shaft 30, the second weight 723 is symmetric with respect to a virtual line passing through the center of the drive shaft 30 and the center of the eccentric bush 72, and the first weight 33 is asymmetric with respect to the virtual line.

Abstract: To improve separation performance of oil. An oil separation structure 55 includes a partition member 62 configured to partition the inside of a separation chamber 42 in the up-down direction. The partition member 62 includes a cylindrical support portion 71 supported by an inner circumferential surface 63 of the separation chamber 42 and a cylindrical swirl acceleration portion having an upper end side continuously formed from the support portion 71, having a smaller diameter than the support portion 71, and having a lower end side closed, and the swirl acceleration portion has a communication path 75 formed, the communication path 75 communicating the radial inside and the radial outside with each other, and accelerates swirling of refrigerant, the refrigerant having descended while swirling along the inner circumferential surface 63 of the separation chamber 42.

Abstract: An object is to optimize a back pressure pressing an orbiting scroll against a fixed scroll in a scroll compressor to which an injection cycle is applied. A back pressure control valve (400) adjusting back pressure (Pm) in a back pressure chamber (H4), adjusts the opening degree of a first valve body (424) increasing and decreasing the flow rate of lubricant which has been separated from gaseous refrigerant compressed in a compression chamber and is supplied to the back pressure chamber (H4), in accordance with suction pressure (Ps) in a suction chamber (H1), discharge pressure (Pd) in a discharge chamber (H2), and injection pressure (Pinj). Then, the back pressure control valve (400) increases and decreases the lubricant flow rate in accordance with injection pressure (Pinj) as well as suction pressure (Ps) and discharge pressure (Pd), to adjust back pressure to target back pressure varying in accordance with injection pressure (Pinj).

Abstract: An object is to optimize a back pressure pressing an orbiting scroll against a fixed scroll in a scroll compressor to which an injection cycle is applied. A back pressure control valve (400) adjusting back pressure (Pm) in a back pressure chamber (H4), adjusts the opening degree of a first valve body (424) increasing and decreasing the flow rate of lubricant which has been separated from gaseous refrigerant compressed in a compression chamber and is supplied to the back pressure chamber (H4), in accordance with suction pressure (Ps) in a suction chamber (H1), discharge pressure (Pd) in a discharge chamber (H2), and injection pressure (Pinj). Then, the back pressure control valve (400) increases and decreases the lubricant flow rate in accordance with injection pressure (Pinj) as well as suction pressure (Ps) and discharge pressure (Pd), to adjust back pressure to target back pressure varying in accordance with injection pressure (Pinj).