To reduce sliding resistance (friction loss) of an outer gear to a pump easing of a trochoidal gear type fuel pump and reduce the pulsation of delivery pressure.
Two inner gears 25, 26 are disposed with a partition wall 28 sandwiched between them with eccentricity on the inner peripheral side of the outer gear 24, and the eccentric directions of both inner gears 25, 26 are shifted from each other to the opposite sides by 180°. Thus, the load in the direction of the outside diameter due to fuel pressure rise is applied from two inner gears 25, 26 to one outer gear 24 in the opposite directions by 180° not to be offset load, so that the sliding resistance of the outer gear 24 to the cylindrical easing 21 is reduced. The number of teeth of the outer gear 24 is set to an odd number, and the number of teeth of the inner gears 25, 26 is set to an even number. Thus, the rotational phases of two inner gears 25, 26 are shifted by half pitch, the phases of pulsation wave of delivery output of two inner gears 25, 26 are shifted by half period of the pulsation wave so as to reduce the pulsation of delivery pressure.
ITO MOTOYA
KUSAYA KATSUHIKO