Double rotation type scroll expander and power generation apparatus including same

A double rotation type scroll expander configured to expand steam, the double rotation type scroll expander comprising:

• a housing having an inflow hole into which the steam is flowable, a first end wall including a first shaft hole, and a second end wall including a second shaft hole that is coaxial with the first shaft hole;
• a first drive shaft configured to extend so as to penetrate the first shaft hole and having an inner end within the housing;
• a first drive bearing provided between the housing and the first drive shaft;
• a second drive shaft provided in the housing coaxially with the first drive shaft such that a part thereof is disposed inside the second shaft hole, and including a second inner end removed from a first inner end of the first drive shaft, and a connecting hole opened in the second inner end so as to communicate with the inflow hole;
• a second drive bearing between the housing and the second drive shaft;
• a first drive scroll including a first drive end plate coupled to the first inner end of the first drive shaft, and a first drive wrap projecting from an opposite side of the first drive end plate to the first drive shaft;
• a second drive scroll including a second drive end plate coupled to the second inner end of the second drive shaft and including a drive through hole communicating with the connecting hole, and a second drive wrap projecting from an opposite side of the second drive end plate to the second drive shaft;
• a driven scroll including a driven end plate disposed between the first drive wrap and the second drive wrap and including a driven through hole in a center thereof, and driven wraps projecting from respective surfaces of the driven end plate, and forming an expansion chamber for expanding the steam on each side of the driven end plate in cooperation with the first drive scroll and the second drive scroll;
• a drive coupling member that couples the first drive scroll and the second drive scroll to each other integrally and rotatably, for the driven scroll to revolve relative to the first drive scroll and the second drive scroll such that a rotary force output to the outside from the first drive shaft is increased;
• a rotation mechanism including a first driven boss and a second driven boss respectively disposed to surround the first drive shaft and the second drive shaft eccentrically to the first drive shaft and the second drive shaft, a first driven arm and a second driven arm extending respectively from the first driven boss and the second driven boss in respective radial directions of the first driven boss and the second driven boss, a first driven coupling member and a second driven coupling member respectively coupling the first driven arm to the driven scroll and the second driven arm to the driven scroll, and a first driven bearing and a second driven bearing provided respectively between the housing and the first driven boss and between the housing and the second driven boss, in a manner that the rotation mechanism supports the driven scroll rotatably;
• and
• a revolving mechanism including a plurality of metal revolving pins provided respectively between the first drive end plate and the first driven arm and between the second drive end plate and the second driven arm, and a plurality of metal revolving discs provided in relation to the respective revolving pins and disposed such that respectively corresponding revolving pins are coupled thereto eccentrically, in a manner that the revolving mechanism couples the driven scroll to the first drive scroll and couples the driven scroll to the second drive scroll to be capable of revolving relative thereto.