Patent ID: 7013877

Claim:
A pressure relief valve for a high-pressure diesel pump of an injection device of a motor vehicle, the pressure relief valve comprising: a valve body, a valve seat; a bore opening into the valve seat and containing a medium under pressure; a piezo drive comprising a tappet forcing the valve body sealingly against the valve seat into a closed position in which the valve body, closes off the bore, relative to a pressure-relief bore of a pressure medium tank; wherein the valve body lifts off the valve seat to release the bore only when the pressure of the medium in the bore surpasses a counter pressure exerted by the piezo drive onto the valve body for forcing the valve body against the valve seat so that excessive pressure of the medium within the bore relative to the counter pressure is relieved by the medium flowing via the pressure-relief bore to the pressure medium tank; wherein the valve body returns into the closed position when the pressure of the medium in the bore drops below the counter pressure exerted by the piezo drive onto the valve body; wherein the piezo drive comprises at least one piezo element connected to the tappet.