a length compensating arrangement between the driving and driven components application_number US 50768200 A description fig1 is a vertical section taken through a cylinder head of a piston type internal combustion engine in the region of an engine valve 1 having a valve stem 2 the valve stem 2 is guided in a sealed manner in a guide 3 of the cylinder head and is coupled with a coil spring 4 which may be exposed to either pressing or pulling forces in the illustrated position the spring 4 is in its relaxed state the free end 9 of the valve stem 2 is connected with a guide rod 11 by a coupling device 10 structured according to the invention the guide rod 11 is affixed to an armature 12 by means of an adjusting device located at the spring 4 the mid position of the armature 12 of the electromagnets may be set between the two spaced electromagnets 14 and 15 which the armature assumes in the de energized state of the electromagnets the length of the spring 4 is so dimensioned that the valve head 6 is at rest in the half open state when the spring 4 is in a relaxed state the gas passage opening 8 bounded by the valve seat 7 is thus half open in case the armature 12 is moved upwardly as viewed in fig1 and thus the spring 4 is compressed the valve head 6 engages the valve seat 7 and thus the gas passage opening 8 is closed if the spring 4 in case of a motion in the opposite direction is exposed.