INTAKE SYSTEM OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To strengthen a vortex flow at an intake port, in an intake system which generates a swirl flow at a combustion chamber by imparting the vortex flow to intake air with the intake port as a vortex structure.SOLUTION: A valve shaft 7b of an intake valve 7 is slidably fit to a guide cylinder 8, and a tip of the guide cylinder 8 forms an exposure part 8a which protrudes to a vortex chamber 4c of an intake port (helical port) 4. Then, a spiral groove 9 which guides a vortex flow of intake air is formed at the exposure part 8a of the guide cylinder 8. It is possible to employ a spiral projection in place of the spiral groove 9. Since a vortex of the intake air is guided at both an external periphery of the vortex chamber 4a and the spiral groove 9, the intake air flows to a combustion chamber 6 as a vortex flow. As a result, a swirl flow 11 can be strengthened.