| 摘要 |
PROBLEM TO BE SOLVED: To provide an injection device capable of inhibiting liquid spray, which is injected from an injection valve for injecting liquid spray into an exhaust passage of an internal combustion engine, from adhering to a wall surface near a nozzle tip.SOLUTION: A part 31 of an exhaust passage 3 of a diesel engine 2 working as an internal combustion engine is formed in a spiral mixer for letting exhaust gas pass in a swirl flow. An injection valve 6 is provided for injecting urea water into the inside of the spiral mixer 31. The injection valve 6 is provided such that a nozzle tip 611 is situated inside a cylindrical part 32. A bypass passage 7 is provided such that one end 71 is connected to a wall surface near the nozzle tip 611 in the cylindrical part 32 and the other end 72 connects with the downstream side of the spiral mixer 31. Urea water spray floating in the cylindrical part 32 is discharged to the downstream side of the spiral mixer 31 via the bypass passage 7. With this, urea water can be inhibited from adhering to the wall surface near the nozzle tip 611. |
