Tachograph for motor vehicles - has erasable recording medium periodically driven before erasing and writing devices

摘要

The tachograph has a speed recorder, a recording device with a medium recording a signal proportional to the speed, and a drive which can be stopped. The recording medium (3) is erasable and an erasing device (4) is allocated to it. The medium (3) is periodically moved by a drive (11) and passes consecutively in front of the erasing and the writing (16) devices. The tachograph requires no servicing and provides a recording of speeds even immediately before an accident.