Fuel feed apparatus with reinforcing structure

#This application is based on and incorporates herein by reference Japanese Patent Applications No. 2003-372747 filed on Oct. 31, 2003 and No. 2004-257478 filed on Sep. 3, 2004.

#The present invention relates to a fuel feed apparatus including a reinforcing structure.

#A fuel feed apparatus disclosed in JP-A-11-168859 has a rotating member such as an impeller received in a pump casing to pressurize fuel drawn from a fuel tank. The fuel flows through a pump chamber formed in the pump casing, and pressure difference is caused due to pressurization of fuel in the pump chamber. In this situation, fuel pressure, i.e., force applied to the pump casing becomes unbalanced, and pump casing may be deformed when the pump casing does not have enough rigidity. Accordingly, clearance between the pump casing and the rotating member decreases, and rotation of the impeller may be locked in the pump casing. As a result, pumping performance may be decreased.

#The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:

#FIG. 1 is a cross-sectional side view showing a fuel feed apparatus according to a first embodiment of the present invention;

#FIG. 2A is a top view showing a reinforcing member, and FIG. 2B is a side view showing the reinforcing member along the line IIB-IIB in FIG. 2A according to the first embodiment;

#As shown in FIG. 1, a fuel pump 2 is received in a fuel tank 4 to supply fuel received in the fuel tank 4 to an engine, so that a fuel feed system such as an electronic fuel injection system is constructed. The fuel pump 2 is an electrically operated pump, and has a motor 10 and a pump 50.

#The motor 10 is a DC-motor with a blush. The motor 10 has a structure in which multiple permanent magnets 16 are cylindrically arranged in a motor chamber 14 that is formed in a cylindrical housing 12. An armature 18 is coaxially arranged in the inner circumferential periphery of the cylindrically arranged permanent magnets 16.

#A bearing 22 is provided to the axial center of an end cover fixed to one axial end of the housing 12. A shaft 24 of the armature 18 is radially supported by the bearing 22 on one axial end thereof. The armature 18 has multiple coils (not shown), to which electricity is supplied from an external power source via terminals 26, a brush (not shown), and a commutator 28 of the armature 18. The terminals 26 are integrally formed in the end cover 20. The power is supplied to the coils, so that the coils respectively generate magnetic fields to rotate the armature 18 that drives the shaft 24 connected to an impellor 52 received in the pump 50.