Fuel Pump

Abstract

A fuel pump for delivering fuel in a motor vehicle, having a side channel stage. The fuel pump further includes a peripheral stage. The peripheral stage produces the same pressure at lower volume flow across the periphery of the rotor as compared to a side channel stage. For this purpose, the cross-sections of the delivery compartments of the peripheral stage are smaller than the cross-sections of the delivery compartments of the side channel stage. The fuel pump therefore has a higher efficiency and is less susceptible to soiling.

1 .- 10 . (canceled) 
   
   
       11 . A fuel pump configured to deliver fuel, comprising:
 an inlet-side casing part having a fluid inlet;   an outlet-side casing part having at least one fluid outlet;   a rotor which is rotatably arranged between the inlet-side casing part and the outlet-side casing part the rotor having rings of guide vanes, the rotor forming:
 a side channel stage having two opposite rings of the rings of the guide vanes configured to form at least one delivery chamber of the side channel stage and delimiting first vane chambers connected to one another, the two opposite rings arranged in the rotor at a distance from a radial outer rim; and 
 a peripheral stage including at least one of the rings of guide vanes configured to form at least one delivery chamber of the peripheral stage and delimiting second vane chambers arranged on the outer rim of the rotor, 
   wherein the delivery chamber of the peripheral stage has a smaller cross-section than the at least one delivery chamber of the side channel stage, and   respective fluid inlets and fluid outlets of the side channel stage and the peripheral stage are connected to one another.   
   
   
       12 . The fuel pump as claimed in  claim 11 , wherein, the side channel stage and the peripheral stage are configured to produce a same pressure across a periphery of the rotor. 
   
   
       13 . The fuel pump as claimed in  claim 11 , wherein
 the fluid inlet of the side channel stage is arranged in the inlet-side casing part and leads to a first face of the rotor, and   the fluid outlet of the side channel stage is arranged in the outlet-side casing part and leads away from a second face of the rotor.   
   
   
       14 . The fuel pump as claimed in  claim 13 , wherein the fluid inlet of the peripheral stage is arranged parallel to the fluid inlet of the side channel stage and leads to the first face of the rotor. 
   
   
       15 . The fuel pump as claimed in  claim 12 , further comprising a spacer ring, configured to hold the casing parts at a distance from one another, the spacer ring comprising a guide element for producing an intended pressure gradient across a periphery of the rotor. 
   
   
       16 . The fuel pump as claimed in  claim 15 , wherein the outlet of the peripheral stage is arranged in the spacer ring and leads radially away from the rings of vane chambers. 
   
   
       17 . The fuel pump as claimed in  claim 15 , wherein the spacer ring has respective recesses at the inlet and at the outlet of the peripheral stage, and between the two recesses on both faces of the rotor, the peripheral stage has delivery chambers which are at least partially separated from one another. 
   
   
       18 . The fuel pump as claimed in  claim 15 , wherein a spacing of an edge of the spacer ring opposite the encircling rim of the rotor is greater proximate the fluid inlet of the peripheral stage than proximate the fluid outlet of the peripheral stage. 
   
   
       19 . The fuel pump as claimed in  claim 17 , further comprising a shell surrounding the casing parts and the spacer rings wherein the shell delimits the recess in the spacer ring radially towards the outside at the fluid outlet. 
   
   
       20 . The fuel pump as claimed in  claim 11 , wherein the outlet-side casing part has a guiding edge sloping in the direction of flow at the outlet of the peripheral stage. 
   
   
       21 . The fuel pump as claimed in  claim 18 , wherein a shell surrounding the casing parts and the spacer ring delimits the recess in the spacer ring radially towards the outside at the outlet. 
   
   
       22 . The fuel pump as claimed in  claim 12 , wherein the peripheral channel stage produces the same pressure with a smaller volume flow than the side channel stage. 
   
   
       23 . A fuel pump configured to deliver fuel, comprising:
 a first casing part having at least one fuel inlet;   a second casing part comprising:
 a first fuel outlet arranged at a distance radially from an outer rim of the second casing part; and 
 a second fuel outlet arranged at the outer rim of the second casing part; 
   a side channel stage comprising:
 a rotor having two mutually opposite rings of first guide vanes delimiting first vane chambers, the two mutually opposite rings of first guide vanes arranged at a distance radially from an outer rim of the rotor; and 
 respective partially annular channels arranged in the first and second casing parts, configured to form at least one side channel delivery chamber having a first cross section, the side channel delivery chamber extending from the fuel inlet to the first fuel outlet; and 
   a peripheral stage comprising:
 the rotor further comprising two peripheral rings of second guide vanes delimiting second vane chambers, the peripheral rings being arranged in the outer rim of the rotor; and 
 respective channels arranged in the first and second casing parts, configured to form at least one peripheral stage delivery chamber having a second cross section extending from the fuel inlet to the second fuel outlet. 
   
   
   
       24 . The fuel pump as claimed in  claim 23 , wherein the second delivery chamber cross section is smaller than the first delivery chamber cross section. 
   
   
       25 . The fuel pump as claimed in  claim 24 , further comprising a spacer ring configured to space the first and second casing parts from one another. 
   
   
       26 . The fuel pump as claimed in  claim 25 , wherein the peripheral stage includes two peripheral stage delivery chambers, wherein the spacer ring has at least one guide configured to separate the peripheral stage delivery chambers.