| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a urea water pump for ensuring reliable operation of a pump part and supplies of urea water by reducing the precipitation of urea crystals even when the urea water left reduced, and also to provide a urea water injection system using the same. <P>SOLUTION: A suction pipe part 50 has an upper curved portion 54 as an uppermost portion located above a pump discharge portion 27 of the pump part 21. Thus, even when the liquid level of the urea water in a urea water tank 11 is lowered, the liquid level position of the urea water in the pump part 21 at the side of a pump suction portion 26 beyond the upper curved portion 54 of the suction pipe part 50 is located at the same level as a lower end 56 of the upper curved portion 54. The pump part 21 is then immersed in the urea water independently of the liquid level position of the urea water in the urea water tank 11. As a result, an impeller 24 and a casing 23 of the pump part 21 are immersed in the urea water to reduce the precipitation of urea crystals on the impeller 24 and the casing 23. <P>COPYRIGHT: (C)2009,JPO&INPIT |
