Two-stroke internal combustion engine
US7520253B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2007 |
| Grant date | Apr 21, 2009 |
| Priority date | — |
| Expiry date | Oct 26, 2027 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B2075/025
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A cylinder bore (4) of a two-stroke internal combustion engine (1) has first scavenging ports (12) and second scavenging ports (13) inside. The first scavenging ports (12) are nearer to an exhaust port (11) of the engine (1) than the second scavenging ports (13). In each scavenging stroke, the second scavenging ports (13) are opened earlier than the first scavenging ports (12) and introduce fuel-free air (A) from the second scavenging ports (13) into a combustion chamber (6). The first scavenging ports (12) are opened later and introduce an air-fuel mixture (M) pre-compressed in a crank chamber (8) into the same combustion chamber (6). Thus, harmful substances contained in exhaust gas discharged from the engine (1) are reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.