Fuel pump assembly
First 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).
1 Assignment
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Accused Products
Abstract
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.
42 Citations
40 Claims
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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). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40)
- 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
Specification