| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a water-cooling type internal combustion engine which makes the flow of cooling water from an inflow passage to an ejection passage smooth and, thereby, improves pump efficiency of a water pump.SOLUTION: A water pump 11 includes a spiral type impeller 17 provided with a number of fins 23 on one surface of a disc 22, an ejection passage 28 being formed on the outer circumference outer side of the impeller 17. The ejection passage 28 has such a shape as to surround the impeller 17 to the extent of a semi circle from bellow. A start edge part 28a of the ejection passage 28 is located on the depth side. An inflow passage 30 assumes an L-type which is opened toward a pump chamber 27 and a crank-shaped channel is constituted with a cooling water return pipe 31 and the inflow passage 30. Cooling water is guided to a crank part and is directed so as to go toward a part 27a located on an inner side of the start edge part 28a of the ejection passage 28 of the pump chamber 27. Therefore, the cooling water which enters the pump chamber 27 is quickly pushed toward the ejection passage 28.</p> |
