Meshing apparatus for starter

An electric starter motor (ESM) drives a drive shaft (DS) (12). A driven shaft (DNS) (16) with an active link to the DS couples to a pinion shaft (PS) (30). A steep screw thread (18) between the DS and the DNS's driver (15) as well as a forward-feed device push the DNS along. The forward-feed device links to the ESM. A single-track spring (36) fits between the DNS's driver and the PS.