Patent · US Expired

Free-piston internal combustion engine

US6035637A · kind A · utility

42Cited by
7References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 25, 1998
Grant dateMar 14, 2000
Priority date
Expiry dateFeb 25, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

This invention is an efficient free-piston internal-combustion engine having an expansion ratio greater than the compression ratio and preferably with gas bearings supporting the piston. The use of gas bearings in combination with high-temperature ceramic materials allows the engine to be nearly adiabatic and with exhaust temperatures in excess of 600.degree. C. These high exhaust temperatures in turn allow the engine to operate as a topping cycle for gas turbines, Stirling engines, steam engines, etc. An improved valving system for flexible control of the engine may include the use of a valve actuator in a piston. In one embodiment, a pair of oppositely disposed combustion chamber passageways extending between the combustion chamber and the earth's atmosphere, each have a combustion-chamber valve for controlling the passage of gas through the passageways. The combustion-chamber valves are essentially simultaneously opened and closed to permit independent variation and control of the compression ratio, expansion ratio, and stroke of the engine. When the valves are opened, the combustion chamber is purged or supercharged with combustion supporting air, and closed to initiate compres…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.