Abstract: A clutch device, particularly for the manual tuning control in a car radio, has the function of positively transmitting, through rack and pinion gears, movement from the tuning knob to the tuning runner. The clutch device comprises a rotating shaft (16) axially reciprocable with respect to frame (10) between an extracted position and an inserted position, with a knob (18) integral with said shaft. Shaft 16 carries a spur gear (20) at its other end, which in the inserted position of the shaft (16) with respect to frame (10) engages a gear wheel (22) integral with a pinion (24) which, cooperating with a rack (56) connected to the usual tuning runner (58) forms a rack and pinion device for positively transmitting movement.

Abstract: A device for disabling the engagement control of the tuning knob, particularly for a keyboard car radio, allows to disable the tuning knob as soon as one of the keys is preset to a corresponding desired station. The device comprises a rocking member (30) having two arms (32) and (34), which has its fulcrum on slide frame (24) of key (12) and a pin (38) integral with key cap (26) of key (12), which key cap (26) is movable on slide frame (24) between an inserted position and an extracted position. The arrangement is such that, in the inserted position of cap (26) with respect to frame (24) of the key, pin (38) locks arm (34) of rocking member (30), which through its other arm (32) moves a slider (20) which controls disengagement of the clutch, thus relieving the control from the tuning knob when key (12) is in its operative position.

Abstract: A pushbutton (keyboard) tuning apparatus for a radio receiver is disclosed. The apparatus comprises a flat tuning key carrying an adjustable and lockable tuning cam means (plunger) which is guided in a slot in the tuning key and locked into position by applying force to an appendage forming part of said slot. Slideable end caps are positioned on each tuning key and each cap carries a pin for selectively applying the force to the locking appendage. Each cap also carries a resilient tongue for actuating clutch disengagement of a manual rotary knob tuning apparatus having a shaft axially displaceable for releasing any pushbuttons previously depressed and being held in their depressed condition.

Abstract: A friction device for coupling the manual tuning knob of a keyboard (pushbutton) radio to a reciprocal tuning slidebar is disclosed. The friction device comprises a cylindrical rod attached to the tuning slidebar which selectively is drivingly engaged by a peripheral V-shaped groove in a pulley rotated by the manual tuning knob.

Abstract: A pushbutton tuner is disclosed in which each pushbutton key can exert an equal force against a slidable tuning element in response to actuation of the key. A link means engages each key during actuation of the key and fixedly positions the key with respect to the tuner frame while a locked adjustable element on the fixed key contacts the slidable tuning element through an elbow lever to position the tuning element.