| 摘要 |
PROBLEM TO BE SOLVED: To provide a six-cycle engine which quickly discharges an exhaust gas from a cylinder after an explosion/expansion stroke after the finish of warmup, suppresses a rise of an engine temperature, and improves engine performance.SOLUTION: In a six-cycle engine, a dynamic valve device 23 which opens and closes an exhaust valve 17 and an intake valve 18 has a cam shaft 26 which is driven at a reduction ratio of one third from a crank shaft 5. The dynamic valve device 23 is constituted so as to be switchable in a warmup mode which performs an exhaust stroke via a re-compression stoke and a re-expansion stroke after sequentially performing an intake stroke and a compression and an explosion/expansion stroke, and a normal operation mode which is transited to the exhaust stoke immediately after sequentially performing the intake stoke and the compression stroke, and the explosion/expansion stoke, and after that, sequentially performs the re-expansion stroke and the re-compression stroke. |
