Robert Boschgmbh

Andreas Jakobi

Dietmar Schmieder

Thomas Sebastian

Gernot Wuerfel

Ingo Kerkamm

Ingo Pietsch

Dietmar Schmiederer

A fuel injection device includes a nozzle needle, an actuator for actuating the nozzle needle, a force sensor for detecting a force applied by the actuator, and a control unit which is connected to the force sensor. The force sensor supplies signals to the control unit and the control unit is designed for determining a position of the nozzle needle and for precisely determining an injected fuel quantity, based on the supplied signal.

Fuel injection device having a needle position determination

A hydraulic coupling is specified, particularly for fuel injectors, which has a housing pot having a pot bottom and a lateral pot surface, a piston guided axially displaceably in the housing pot, a fluid-filled coupling gap that is provided between the piston and the pot bottom, diaphragm situated on the outer side of the housing pot facing away from the piston, a compensation chamber that is bordered by the diaphragm and flow-connected to the coupling gap, and a spring element acting upon the diaphragm with an axially directed spring force. In order to achieve a low overall stiffness of the hydraulic coupling at the required specified coupling force, the spring element is developed as a spring bracket fixed to the housing pot, which lies against the diaphragm with axial prestressing in the region of the pot bottom.

Hydraulic coupling

A positioning device includes a positioning element that is situated movably in a first direction and a second direction, the first and the second directions being opposed to one another, and a first piezoelectric actuator and a second piezoelectric actuator, the first piezoelectric actuator moving the positioning element in the first direction and the second piezoelectric actuator moving the positioning element in the second direction.

Positioning device

An injector for a fluid, particularly for fuel, is provided having a valve housing, a fluid intake, a valve chamber having a spray-discharge orifice, a piezoelectric or magnetostrictive actuator situated in the valve housing and a fluid-guiding pipe connecting a fluid intake and a valve chamber, which is situated in the valve housing running along the actuator. In order to create structural space in the valve housing for guiding through the fluid-guiding pipe which has a sufficiently large diameter for reducing pressure drops in the intake region, a hollow cylinder surrounding the actuator and developed as a prestressed spring is provided with a cylinder wall opening that extends axially through the entire length, and the positioning of the fluid-guiding pipe in the valve housing is undertaken so that it extends radially into the cylinder wall opening.

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Stuttgart, Germany

Andreas Jakobi