Patent ID: 7237533

Claim:
An arrangement in a fuel injection system for controlling the fuel injection, the arrangement comprising a body part having a space arranged therein, through which space the fuel to be injected during operation flows, and a fuel inlet opening and an outlet opening opening into the space, additionally the arrangement further comprises a piston means arranged movably inside the space, the piston means having a channel arranged therein for creating a flow connection between the fuel inlet opening and the outlet opening, whereby in the arrangement the piston means can divide the space into a first part being in connection with the inlet opening and a second part being in connection with the outlet opening, the arrangement further comprising a spring for creating a force acting on the piston means in a direction opposite to the main direction of the fuel flow, wherein in the arrangement the piston means and the body part delimit at least one third part as the piston means is in the end adjacent the inlet opening or near it, the volume of the third part being dependent on the mutual positions of the piston means and the body part.