Push button type tuner

In a push button type tuner including supporting means, tuning means mounted on said supporting means to generate a tuned frequency and being movable to a position corresponding to the tuned frequency, and a plurality of presettable channel selecting mechanisms for selectively displacing the tuning means to the position corresponding to a frequency specified for each of said channel selecting mechanisms, the improvement comprising:

• each of the channel selecting mechanisms comprising a rotatable actuating member displaceable between a fore inoperative position and a rear operative position relative to the supporting means, said actuating member being normally urged toward the fore inoperative position and including a main rotatable portion and a push button which serves as a rotary knob, said push button being fixedly secured to the foremost end of the actuating member,
• the actuating member coacting with a pair of rotatable channel selecting members which are displaceable between the fore inoperative position and the rear operative position, said channel selecting members being so mounted on the supporting means that they are normally urged toward the fore inoperative position and each of the channel selecting members having a follower rotatable portion selectively engageable with the main rotatable portion to rotate with the latter, each of the channel selecting members having a longitudinally extending threaded portion on which is threadably mounted a channel selecting dog, said channel selecting dog being displaceable in the forward and rearward directions as the channel selecting member rotates,
• an engagement mechanism mounted on the actuating member so as to effect engagement of the actuating member with the channel selecting members so that the latter are alternately displaced toward the rear operative position of the actuating member at every time when a cycle of forward and rearward movements of the actuating member between the fore inoperative position and the rear operative position is achieved,
• the tuning means including an actuating plate engageable with the channel selecting dog on the channel selecting member which is located at the rear operative position to enable the tuning means to be adjusted by the actuating plate, and,
• the tuner further including a locking member having means for allowing rotation of the main rotatable portion to be transmitted to the follower rotatable portion when one of the channel selecting members is located at the rear operative position and to unlock the one channel selecting member which has assumed the rear operative position from the locked state when the other channel selecting member reaches the rear operative position.