Diesel engines are being equipped with pump and nozzle systems at an ever higher rate. In these systems, a pump tappet located in the upper part of the injector is moved by the camshaft. This generates the high pressure needed in the injector. The injection profile is controlled via an electromagnetic switch device. A KERN-LIEBERS spring in the injector ensures safe closing of the valve needle and KERN-LIEBERS springs reset the electromagnetic switch device.

KERN-LIEBERS compression springs are also used in the new Common Rail injection system. They aid the precise opening and closing actions required in the electrovalve-controlled injector when the diesel oil is injected.