Multiple-cylinder, free-piston, alpha configured stirling engines and heat pumps with stepped pistons
US7171811B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2005 |
| Grant date | Feb 6, 2007 |
| Priority date | — |
| Expiry date | Sep 29, 2025 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02G2244/52
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An improved, free-piston, Stirling machine having at least three pistons series connected in an alpha Stirling configuration. Each cylinder is stepped so that it has a relatively larger diameter interior wall and a coaxial, relatively smaller diameter interior wall. Each piston is also stepped so that it has a first component piston having an end face facing in one axial direction and matingly reciprocatable in the smaller diameter cylinder wall and a second component piston having an end face facing in the same axial direction and matingly reciprocatable in the larger diameter, cylinder wall. One of the piston end faces bounds the compression space and the other end face bounds the expansion space. Preferably, each stepped piston has peripheral, cylinder walls that are axially adjacent and joined at a shoulder forming the end face of the larger diameter component piston. Stirling machines with these stepped features are also arranged in various opposed and duplex configurations, including arrangements with only one load or prime mover for each opposed pair of pistons. Improved balancing or vibration reduction is obtained by connecting expansion and compression spaces of a four cyl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.