| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an urea water injection device reducing local accumulation of urea crystal and clogging of injection hole caused by deposition of urea, and securing sure injection and injection stop of urea water. <P>SOLUTION: A seal part 39 of a needle 32 intermits injection of urea water from the injection hole 33 by being seated on and separated from a valve seat 34 formed at a more tip side of the injection hole 33 formed by a body 31. A head part 37 having the seal part 39 formed thereon includes a groove 43 at a conical shape shaft part 36 side. When urea water is injected from the injection hole 33, part of the urea water passes through the groove 43 of the head part 37. Consequently, the needle 32 receives reaction force from urea water flowing in the groove 43 and turns every injection of the urea water. As a result, local growth of urea crystal deposited from urea water staying around the injection hole 33 is reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT |
