A timer has a single knob which is normally used to set a desired timing cycle within a given range and also, when pulled out, to set a selected one of a plurality of ranges. When the knob is pulled out, projections formed on the control shaft engage a concentrically-mounted rotatable disc having at...http://www.google.fr/patents/US4410774?utm_source=gb-gplus-shareBrevet US4410774 - Single knob variable range timer
