Patent ID: 7455299
Filing Date: 2008-11-25
Classification: B60K,F02M,F16J,F16L

Abstract:
1. An elastic sealing member for a fuel tank made of resin and adapted for a vehicle, the elastic sealing member being arranged between a cylindrical wall portion standing upright on an outer surface of a tank body of the fuel tank and including an opening portion on an upper end of the cylindrical wall portion, and a base body of a fuel pump unit for holding a fuel pump to provide a seal therebetween, the base body having a fit portion of cylindrical shape for fitting to an inner peripheral surface of the cylindrical wall portion, a closing portion on an upper end thereof for closing the opening portion of the cylindrical wall portion, and an annular flange portion projecting radially outwardly at an upper position with respect to an upper end of the cylindrical wall portion, the elastic sealing member for the fuel tank, comprising: a cylindrical sealing portion interposed and arranged between the base body and the cylindrical wall portion, an annular flange sealing portion projecting radially outwardly on an upper end of the cylindrical sealing portion, the flange sealing portion being sandwiched between an upper end surface of the cylindrical wall portion and the flange portion of the base body by tightening a screw-on cap on an externally threaded portion of an outer peripheral surface of the cylindrical wall portion, wherein: the flange sealing portion is formed with a main circumferentially annular sealing protrusion protruding from a front surface thereof facing the flange portion of the base body and a rear surface thereof facing the upper end surface of the cylindrical wall portion, respectively, the cylindrical sealing portion is formed with a sub circumferentially annular sealing projection projecting radially outwardly from an outer peripheral surface thereof, the main sealing protrusions provide a sealing function on the flange sealing portion and the sub sealing projection provides a sealing function on the cylindrical sealing portion, the sub sealing projection is entirely angled in an inserting direction of the elastic sealing member into the cylindrical wall portion and defines a maximum outer diameter larger than an inner diameter of the cylindrical wall portion, when angles defined by upper and lower surfaces of the sub sealing projection with respect to the outer peripheral surface of the cylindrical sealing portion at a base portion thereof are indicated by θ the sub sealing projection has an arcuate cross-section on a leading end portion thereof, when a curvature radius of the leading end portion of the sub sealing projection is indicated by R, and an axial length of the base portion of the sub sealing projection is indicated by C, a relationship between R and C satisfies the following condition,