Fluid machine for converting heat energy into mechanical rotational force

A fluid machine for converting heat energy into mechanical driving force comprising:

• a housing;
• an expansion device housed in the housing and forming a part of Rankine cycle for collecting heat energy from refrigerant and converting the collected heat energy into the mechanical driving force, the Rankine cycle being further formed from a heating device for heating the refrigerant for the Rankine cycle by heat energy of the working fluid flowing through the heating device and a condenser for condensing the refrigerant from the expansion device;
• an electric rotating device rotationally supported in the housing and selectively operating as an electric motor for generating rotational force and as an electric power generator for generating electric power;
• a pump device housed in the housing and operatively connected to the expansion device and the electric rotating device, so that the pump device is operated by one of the mechanical driving force from the expansion device and the rotational force from the electric rotating device, wherein the pump device forms a part of the Rankine cycle for pressurizing and feeding liquid-phase refrigerant from the condenser to the heating device;
• and
• a shaft rotationally supported in the housing and operatively connecting the expansion device, the electric rotating device and the pump device,
• wherein the electric rotating device is operated as the electric motor for rotating the pump device to start up the operation of the Rankine cycle, and operated as the electric power generator by the mechanical driving force from the expansion device after the expansion device has started with its operation,
• wherein the housing further defines a tank for receiving the liquid-phase refrigerant, such that the liquid-phase refrigerant is fed to the pump device,
• wherein the expansion device, the electric rotating device and the pump device are arranged in a vertical direction, the pump device is arranged in its vertical direction at a lower position than the other two components, and an inlet port of the refrigerant from the condenser is formed in the housing at a position higher than the electric rotating device in the vertical direction,
• wherein the tank is formed at the vertically lowermost position of the housing for receiving and keeping the liquid-phase refrigerant.