초록 ▼

The device includes a solenoid valve having a supply conduit communicating with the delivery of the pump, a drain conduit, an electromagnet energizable to control an armature controlling a shutter, and reducing means for reducing disturbance in the delivery pressure of the pump when the electromagne

The device includes a solenoid valve having a supply conduit communicating with the delivery of the pump, a drain conduit, an electromagnet energizable to control an armature controlling a shutter, and reducing means for reducing disturbance in the delivery pressure of the pump when the electromagnet is energized. The reducing means include a chamber having a predetermined volume and located between the supply conduit and the drain conduit; and a fixed shield having an opening in which slides a small-diameter portion of the stem of the armature. The electromagnet is controlled by an electronic unit via a modulator for modulating the duty cycle of the control pulses, and via a circuit for selecting the frequency of the control pulses on the basis of an estimate of hydraulic disturbances depending on at least one operating parameter.

대표청구항 ▼

1. A device for regulating a delivery pressure of a pump for feeding fuel to an internal combustion engine, the device comprising a solenoid valve having a supply conduit communicating with a delivery conduit of said pump, a drain conduit, a shutter between said supply conduit and said drain conduit

1. A device for regulating a delivery pressure of a pump for feeding fuel to an internal combustion engine, the device comprising a solenoid valve having a supply conduit communicating with a delivery conduit of said pump, a drain conduit, a shutter between said supply conduit and said drain conduit, an electromagnet energized variably to control an armature controlling said shutter, a cutoff chamber for cutting off hydraulic pressure between said supply conduit and said drain conduit, said cutoff chamber being of such a volume as to reduce variation in said hydraulic pressure on said armature, wherein said armature comprises a cylindrical stem having a portion housed in said cutoff chamber and connected to said stem by a shoulder, said portion having a diameter smaller than a diameter of said stem to increase the volume of said cutoff chamber, and a fixed shield defining said cutoff chamber and having an opening in which said portion slides so as to eliminate a piston effect of the hydraulic pressure in said chamber on said stem.