Injection valve comprising a pump piston

The invention relates to an injection valve comprising a booster piston, said piston delimiting a pump chamber and a booster chamber. A valve is provided in the inlet to the chamber. The valve is configured as a 3/2-way valve and controls the pressure in the pump chamber. The pressure in the pump chamber is converted into a correspondingly increased pressure in the booster chamber and in an injection chamber containing an injection needle, by means of the booster piston. The use of the valve allows a precise control of the injection times.