US 6,553,972 B1 · Fuel pump control device

Abstract

To provide a fuel pump control device allowing a fuel pump having a small capacity to feed a sufficient amount of fuel to an internal combustion engine. During running of a vehicle at a low speed (for example, less than 2,0 km/hr), pulsed drive voltages are intermittently supplied to a fuel pump in accordance with each opening/closing of a thyristor on the basis of ignition pulses of the engine. In this way, the fuel pump repeats discharge operation at a relatively long cycle in synchronization with the pulsed drive voltages. During running of the vehicle at a high speed, a drive voltage is continuously supplied (that is, a DC voltage is supplied) from a power supply line to the fuel pump, whereby the fuel pump repeats discharge operation at a cycle with a short self-excitation state.

Claims3

Dependent claims

A fuel pump control device for controlling an electrically-operated fuel pump for supplying fuel to an internal combustion engine, said control device comprising:

a vehicle operating state deciding means for generating a vehicle operating state signal representative of a operating state of a vehicle;
comparing means for comparing said vehicle operating state signal with a specific value;
and
controlling means, for controlling opening/closing of a connection between said fuel pump and a power supply line in accordance with the comparison result obtained by said comparing means, said controlling means including a thyristor operatively connected to said fuel pump for selectively supplying power thereto and a drive coil and a switching relay for selectively connecting said drive coil to said fuel pump, said switching relay including a first contact for connecting said drive coil to said fuel pump when the drive coil is in an excited state and a second contact for connecting the thyristor to said fuel pump when the drive coil is in a non-excited state.

1 more element

Dependencies are inferred from the claim text.

Fuel pump control device

Life of this patent

Fuel pump control device

Life of this patent

Abstract

Claims3