The adjusting movement of a control knob on a control device in the passenger compartment of an automobile is transferred to an air vent in an air shaft which leads to the passenger compartment in a simple manner requiring little space and few parts. A flexible steel shaft is coupled to the torque shaft of the control knob at an oblique angle to this torque shaft by way of a universal joint connection. To simplify construction, a first retainer for the universal joint is designed in one piece with the control knob torque shaft, and a second retainer is designed in one piece with an intermediate shaft to which the flexible steel shaft connected.