초록 ▼

The invention relates to a fuel pump assembly having a low-pressure region (ND) with at least one low-pressure pump-and a high-pressure region (HD) with at least one regulated-quantity high-pressure pump, which pumps a quantity of fuel required to compensate for the quantitative balance in the high-

The invention relates to a fuel pump assembly having a low-pressure region (ND) with at least one low-pressure pump-and a high-pressure region (HD) with at least one regulated-quantity high-pressure pump, which pumps a quantity of fuel required to compensate for the quantitative balance in the high-pressure region, the quantity regulation being effected via a metering unit which is disposed between the low-pressure pump and the high-pressure pump. In order, by simple and sturdy means with high availability and a long service life, to prevent the fuel quantity in correctly pumped by the metering unit at certain operating points from reaching the high-pressure region, the invention proposes that the pumping flow of the low-pressure pump is greater than the pumping flow of the high-pressure pump; that a fuel return line branches off between the metering unit and the high-pressure pump and discharges into the inlet of the low-pressure pump; and that a control element is disposed in the return line.

대표청구항 ▼

[ We claim:] [1.] A fuel pump assembly (1), having a low-pressure region (ND) with at least one low-pressure pump (2) and a high-pressure region (HD) with at least one regulated-quantity high-pressure pump (3), which pumps a quantity of fuel required to compensate for a quantitative balance in the h

[ We claim:] [1.] A fuel pump assembly (1), having a low-pressure region (ND) with at least one low-pressure pump (2) and a high-pressure region (HD) with at least one regulated-quantity high-pressure pump (3), which pumps a quantity of fuel required to compensate for a quantitative balance in the high-pressure region, the quantity of fuel regulation being effected via a metering unit (5) disposed between the low-pressure pump (2) and the high-pressure pump (3), wherein a pumping flow of the low-pressure pump (2) is greater than a pumping flow of the high-pressure pump (3); a fuel return line (8) branches off between the metering unit (5) and the high-pressure pump (3) and discharges into an inlet of the low-pressure pump (2); and a control element (9, 26) is disposed in the fuel return line (8).