| 摘要 |
PURPOSE:To reduce the generation of evaporated gas by providing a throttle part between a movable valve and a valve seat, forming the shoulder part of a valve seat holding member into a smooth curved surface at the time of passing fuel, and providing the end surface of the valve seat holding member on the same plane as the end surface of the valve seat. CONSTITUTION:The inner part of a housing 5 is partitioned by a diaphragm 2 into an air chamber 3 and a fuel chamber 4, and a movable valve 13 and valve seat 14 provided in the fuel chamber 4 form a throttle part. The valve seat 14 has a fuel passage 14a continued to a fuel discharge pipe 9 forming a discharge passage of fuel, and the fuel passage 14a has the form in which the sectional area is gradually increased from inlet side to outlet side. A valve seat holding member 8 is provided in such a manner that the end surface facing the movable vale 13 has the same plane as the inlet side end. surface of the valve seat 14, and the shoulder part extending from the end surface facing the movable valve 13 to the outer circumferential side surface is formed from a smooth curved surface. Thus, the flow of the fuel flowing into the fuel passage 14a is smoothed, and the generation of evaporated gas can be reduced. |
