Fuel Pump For Internal Combustion Engines

Abstract

A fuel pump is disclosed, especially a prefeed pump for feeding aircraft fuel to the high pressure pump, wherein the form-fit connection between the drive shaft ( 4 ) and the driven impeller ( 2 ) is produced by a regular, convex, triangular polygonal contour having rounded-off lateral faces and corner faces, the drive shaft and the impeller being provided with the polygonal contour. In this manner, the wear resulting from the poor lubricating power of the kerosene-based aircraft fuel can be reduced and the service life of the fuel pump can be increased.

1 . A fuel prefeed pump for supplying fuel to a high pressure fuel pump for supplying diesel engines operated with aircraft fuel comprising a gear pump having a pump gear driven via a driveshaft, a form-fit connection between the driven pump gear ( 2 ) and the driveshaft ( 4 ) embodied as a regular convex polygon having lateral faces and corner regions curved to an outside thereof. 
     
     
         2 . The fuel prefeed pump according to  claim 1 , characterized in that the form-fit polygon connection comprises a coupling disc ( 5 ) provided on the driveshaft ( 4 ) and a recess ( 6 ) moulded into the driven pump gear ( 2 ) having the corresponding polygonal contour. 
     
     
         3 . The fuel prefeed pump according to  claim 1 , characterized in that the convex polygonal contour is triangular and in a radius R S  has lateral faces curved to the outside and in a radius R E  has corner regions curved to the outside. 
     
     
         4 . The fuel prefeed pump according to  claim 1 , characterized in that the regular convex polygonal contour is a tetragon contour or a pentagon contour. 
     
     
         5 . The fuel prefeed pump according to  claim 2 , characterized in that the convex polygonal contour is triangular and in a radius R S  has lateral faces curved to the outside and in a radius R E  has corner regions curved to the outside. 
     
     
         6 . The fuel pump according to  claim 2 , characterized in that the regular convex polygonal contour is a tetragon contour or a pentagon contour.