Patent ID: 8092186

Claim:
An impeller for a fuel pump comprising: at least two blades, wherein the blades have an incremental angle set by an expression below: Δθ ⁢ ⁢ i = ( 360 N ) + ( - 1 ) i × Am × sin ⁡ ( p 1 × 360 N × i ) × cos ⁡ ( P 2 × 360 N × i ) , where ΔθI is the incremental angle between the blades, N is the total number of blades (N=2, 3, 5, 7, 11, 13, 17, . . . ), Am is the distribution magnitude of the inter-blade interval (equally divided angle) (0<Am<360/N), i is the order of the blade (i=1, 2, 3, . . . , N), and P 1 and P 2 are the factors exerting an influence on the cycle (0<P 1 <N, and 0≦P 2 ≦N); and the incremental angle has maximum and minimum values a difference of which satisfies an expression: 2°≦MAX−MIN≦6°, where MAX is the maximum value, and MIN is the minimum value of the incremental angle.