Abstract: The invention relates to an adjusting device for an oscillating workpiece. In one type of gear grinding machine, there is provided means for effecting oscillation of the workpiece simultaneously and in synchronism with reciprocation thereof in order to enable an involute curve to be ground onto the workpiece by a grinding wheel which is fixed except for its rotation. In such machine, this oscillation is created by one or more cams fixed to the workpiece spindle, together with at least two bands fixed at one of their respective ends to such cam and at the other of their respective ends to a fixed portion of the machine with the bands being wrapped at least partially around such cam. Thus, sidewise reciprocating movement of the workpiece spindle effects oscillation of same in a known manner according to the curve provided on said cams.