Assignment

In earlier times, the electric fuel pump was very often the first part of the fuel injection which resigned due to dirt. The filter was, and still is, arranged behind the pump. Thus, the displacement pump was substituted by a flow pump. In addition, the feeding of gas bubbles can be reduced. The reduction is even stronger with a side channel pump as preliminary stage. All together the peripheral pump, as compared to other flow pumps, manages relatively high pressures with small feed quantities and a small shape.

Function

The name 'peripheral pump' points to a round channel in the case from suction to pressure opening. Between both channels it is interrupted to prevent a back flow from the pressure to the suction side. During the feed process the fuel in the suction channel delivers its energy to the fuel already in the circulation channel, between mostly 20 blades. The pump does not yet reach the efficiency of 20% of the displacement pump, but the pressure of a little more than 4 bar is sufficient for all modern, indirectly injecting systems.