| 摘要 |
A fuel pump with improved pumping performance having a high motor torque and a sufficient cross sectional area of fuel passage is provided. The motor section (2) of the fuel pump has a columnar rotor (21) having a shaft (7) for rotating the pump section (1), and a ring magnet (5, 35, 45, 55, 65, 75, 85) surrounding an outer circumference face of the rotor (21). There is provided a minute clearance between the rotor (21) and the magnet (5, 35, 45, 55, 65, 75, 85). The motor section (2) further has a cylindrical yoke (4, 34, 46, 56, 66) surrounding and contacting an outer circumference face of the magnet (5, 35, 45, 55, 65, 75, 85). A fuel passage (27, 37, 47, 57,67, 77, 87, 97, 127) having a sufficient cross sectional area is formed at a location removed from a magnetic path along which a substantial portion of magnetic flux (F) flows between the rotor (21), the magnet (5, 35, 45, 55, 65, 75, 85), and the yoke (4, 34, 46, 56, 66).
|
