Pre-setting fine tuning device for a turret type television tuner

摘要

The present television fine tuning is so constructed that an initial rotation establishes the fine tuning state and that a continued rotation of the fine tuning shaft performs the fine tuning. For this purpose the present tuner comprises a fine tuning driving member, a rotation transmitting idler member, a plate spring for supporting the idler member and a fine tuning driven member. The driving member includes a fine tuning shaft, a slide gear and a slip clutch mounted in front of a chassis concentrically around a channel selector shaft supported in the chassis. The spring member has freely slidable end portions disposed between the chassis and the slide gear for biasing the slide gear in the forward direction. The idler member is movably arranged on the spring member for transmitting the fine tuning movement. The slide gear has a gear back of a flange and a driven cam surface in the front of the flange and is operatively mounted around the slip clutch. The fine tuning shaft has a driving cam cooperating with the driven cam surface of the slide gear. A change in the shape of the plate spring shifts the idler member axially in response to initial rotation of the fine tuning shaft.