Fuel pump

Abstract

A fuel pump includes a plurality of magnets that are disposed circumferentially on an inner surface of a housing of the fuel pump and alternately form different magnetic poles, an armature rotatably disposed inside the permanent magnets, a rotating member disposed on a rotary shaft that is connected with the armature and rotates with the rotary shaft by rotating the armature, a pump casing that accommodates and rotatably supports the rotating member, and a discharge port disposed on the pump casing so as to discharge fuel pressurized by the rotation of the rotating member. According to the present invention, an imaginary line extending straight through the discharge port in a flow direction of fuel discharging from the discharge port extends into a circumferential gap between two of said permanent magnets.

1 . A fuel pump for supplying fuel suctioned from a fuel tank to an internal combustion engine, comprising:
 a housing;   a plurality of magnets that are disposed circumferentially on an inner surface of said housing, and forming different magnetic poles alternately;   an armature disposed rotatably inside the permanent magnets;   a rotating member disposed on a rotary shaft that is connected with the armature and rotates with the rotary shaft by rotating the armature;   a pump casing that accommodates and rotatably supports the rotating member; and   a discharge port disposed in the pump casing to discharge fuel pressurized by the rotation of the rotating member;   wherein:   an imaginary line extending straight through the discharge port in a flow direction of fuel discharging from the discharge port extends into a circumferential gap between two of said permanent magnets.   
   
   
       2 . The fuel pump according to  claim 1 , wherein:
 said imaginary line extends along an inner inclined surface of the discharge port.   
   
   
       3 . The fuel pump according to  claim 1 , wherein:
 an edge between an inner inclined surface of the discharge port and an outer surface of the pump casing is disposed axially below said circumferential gap.   
   
   
       4 . A fuel pump for supplying fuel suctioned from a fuel tank to an internal combustion engine, comprising:
 a housing;   a plurality of magnets that are disposed circumferentially on an inner surface of said housing, and forming different magnetic poles alternately;   an armature disposed rotatably inside the permanent magnets;   a rotating member disposed on a rotary shaft that is connected with the armature and rotates with the rotary shaft by rotating the armature;   a pump casing that accommodates and rotatably supports the rotating member; and   a discharge port disposed in the pump casing to discharge fuel pressurized by the rotation of the rotating member;   wherein:   an imaginary line extending in a flow direction of fuel discharging from the discharge port along an inner inclined surface of the discharge port extends between upstream ends of adjacent permanent magnets.   
   
   
       5 . The fuel pump according to  claim 4 , wherein:
 a distance d between an edge face of the permanent magnets which face the pump casing and an opening of the discharge port which faces the permanent magnet is equal to or less than 10 mm.   
   
   
       6 . The fuel pump according to  claim 4 , wherein:
 there are two permanent magnets.   
   
   
       7 . The fuel pump according to  claim 6 , wherein:
 a circumferential angle θ of the permanent magnets is equal to or less than 150 degrees and more than 120 degrees.   
   
   
       8 . The fuel pump according to  claim 4 , wherein:
 an angle between the imaginary line and the outer surface of the pump casing is equal to or less than 60 degrees and more than 10 degrees.   
   
   
       9 . A fuel pump for supplying fuel suctioned from a fuel tank to an internal combustion engine comprising:
 a housing;   a plurality of magnets that are disposed circumferentially on an inner surface of said housing, and forming different magnetic poles alternately;   an armature disposed rotatably inside the permanent magnets;   a rotating member disposed on a rotary shaft that is connected with the armature and rotates with the rotary shaft by rotating the armature;   a pump casing that accommodates and rotatably supports the rotating member; and   a discharge port disposed on the pump casing to discharge fuel pressurized by the rotation of the rotating member;   wherein:   an edge between an inner inclined surface of the discharge port and an outer surface of the pump casing being disposed axially below a circumferential gap formed between two of said permanent magnets.   
   
   
       10 . The fuel pump according to  claim 9 , wherein:
 a distance d between an edge face of the permanent magnets which face the pump casing and an opening of the discharge port which faces the permanent magnet is equal to or less than 10 mm.   
   
   
       11 . The fuel pump according to  claim 9 , wherein:
 there are two permanent magnets.   
   
   
       12 . The fuel pump according to  claim 11 , wherein:
 a circumferential angle θ of the permanent magnets is equal to or less than 150 degrees and more than 120 degrees.