Impeller for fuel pump and fuel pump in which the impeller is employed

Abstract

An impeller is employed for a fuel pump and boosts a pressure of fuel by rotating the fuel in a pump passage formed in the fuel pump in a rotational direction of the impeller. The impeller includes a plurality of vane grooves formed adjacent to each other in the rotational direction of the impeller and a plurality of vanes formed adjacent to each other in the rotational direction. Each one of the plurality of vanes divides one of adjacent two of the plurality of vane grooves from the other. A difference between a maximal value and a minimum value of an adjacent vane angle is set in a range of 2.5° to 4°. A fuel pump includes a motor unit, the impeller, and a casing member. The impeller is rotated by rotation driving force of the motor unit. The casing member rotatably receives the impeller and defines the pump passage.

1 . An impeller that is employed for a fuel pump and boosts a pressure of fuel by rotating the fuel in a pump passage, which is formed in the fuel pump in a rotational direction of the impeller, the impeller comprising:
 a plurality of vane grooves formed adjacent to each other in the rotational direction of the impeller; and   a plurality of vanes formed adjacent to each other in the rotational direction of the impeller, wherein:
 each one of the plurality of vanes divides one of adjacent two of the plurality of vane grooves from the other; and 
 a difference between a maximal value and a minimum value of an adjacent vane angle is set in a range of 2.5° to 4°, wherein the adjacent vane angle is an angle, which is made around a rotational axis of the impeller between respective ends of adjacent two of the plurality of vanes in the rotational direction of the impeller. 
   
   
   
       2 . The impeller according to  claim 1 , wherein each adjacent vane angle is set in a range of 8° to 12°. 
   
   
       3 . A fuel pump comprising:
 a motor unit;   the impeller recited in  claim 1 , wherein the impeller is rotated by rotation driving force of the motor unit; and   a casing member that rotatably receives the impeller and defines the pump passage.