Patent ID: 8408024

Claim:
A fluid machine comprising: a first closed casing including a first oil sump formed in its bottom and an internal space filled with a working fluid above the first oil sump; a first motor disposed inside the first closed casing; a first compression mechanism disposed inside the first closed casing for compressing the working fluid; an expansion mechanism disposed inside the first closed casing for recovering power from the expanding working fluid; a first shaft coupling the first motor, the first compression mechanism and the expansion mechanism; a first oil pump for drawing oil of the first oil sump through a first oil-suction opening and supplying the oil to one or both of the first compression mechanism and the expansion mechanism through a first oil-supply passage that is provided in the first shaft and extends above the first oil sump; a first suppressing member disposed so as to horizontally partition a space inside the first closed casing, for preventing the oil of the first oil sump from flowing with the flow of the working fluid inside the first closed casing; a second closed casing including a second oil sump formed in its bottom and an internal space filled with a working fluid above the first oil sump; a second motor disposed inside the second closed casing; a second compression mechanism disposed inside the second closed casing for compressing the working fluid, the second compression mechanism being connected in parallel with the first compression mechanism in a working fluid circuit by interconnection between the first closed casing and the second closed casing through a pipe; a second shaft coupling the second motor and the second compression mechanism; a second oil pump for drawing oil of the second oil sump through a second oil-suction opening and supplying it to the second compression mechanism through a second oil-supply passage provided in the second shaft; and a second suppressing member disposed so as to horizontally partition a space inside the second closed casing, for preventing the oil of the second oil sump from flowing with the flow of the working fluid inside the second closed casing, wherein a volumetric capacity of a first available oil space from the first suppressing member to the first oil-suction opening inside the first closed casing is larger than a volumetric capacity of a second available oil space from the second suppressing member to the second oil-suction opening inside the second closed casing.