Cranking device for internal combustion engines

A cranking device for internal combustion engines, comprising a starter motor whose starter pinion initially shifts into a gear ring of the engine with a starting signal via an engagement magnet, before the starter motor trips the cranking process with full force;

• a logic circuit (L);
• a first triggered semiconductor;
• a second triggered semiconductor;
• a protective resistor (Rvor), and a travel sensor wherein:
• the starter motor (SM) with the starting signal (st) drives the starter pinion initially via the protective resistor (Rvor) with reduced torque, and the engagement magnet (EM) shifts into the gear ring of the engine, and
• after the shifting, the engagement magnet (EM) presses the starter pinion all the way into the gear ring of the engine, and the starter motor (SM) turns the engine over with full torque by bypassing the protective resistor (Rvor), and wherein:
• the starting signal (st) is delivered to the logic circuit (L) which via the first triggered semiconductor configured as a highside smart FET (T1), imposes reduced current on a series circuit comprising the protective resistor (Rvor) and the starter motor (SM);
• the logic circuit, via the second triggered semiconductor configured as a highside smart FET (T2), triggers the engagement magnet (EM) in clocked fashion, until the starter pinion shifts into the gear ring of the engine;
• the second semiconductor (T2) is connected in series with the first semiconductor (T1), and
• after the shifting of the starter pinion, the second semiconductor (T2) is made fully conducting via the logic circuit (L), and
• the shifting of the starter pinion into the gear ring of the engine is monitored by means of the travel sensor (WS) and is indicated to the logic circuit (L);
• the logic circuit (L), as a function of the response of the travel sensor (WS), switches the second semiconductor (T2) from a clocked operation to continuous operation.