DRUCKTASTENABSTIMMEINRICHTUNG

摘要

1,110,860. Push-button tuning. MOTOROLA Inc. 12 April, 1967 [18 May, 1966], No. 16716/67. Heading H3Q. [Also in Division F2] In a push-button tuner the buttons can be mechanically coupled to either of two tuning elements via presettable cams on actuating devices operated by the buttons, and a device is provided integral with each actuating device for locking and unlocking the cams. The invention is described in connection with an AM/FM receiver having separate tuners operated simultaneously by each button, with a switch to effect the necessary electrical connections. The buttons are arranged on a guide 22 (Fig. 1) which has a number of arch-shaped pieces 37-40 co-operating with a sliding bar 30. When this bar is moved to the left (as in Fig. 1) projections 34, 35 push down the pieces 37, 39 and the whole button assembly moves downwards to its lower position (e.g. AM). When the bar 30 is moved to the right (as in Fig. 2, not shown) the projections 34, 35 move into the arch-shaped pieces and push the button assembly into its upper position (e.g. FM). In this operation the guide 22 moves up or down behind bent fingers 26 attached to the frame. Each button contains a slide 47 (Fig. 3) bearing a pin 60 which, by means described below, can push in one or other of two plungers 49, 50 depending on the vertical position of the assembly 22. Each plunger carries an adjustable cam 66, 67 which can be set to move a treadle 42 by a predetermined amount when the button is pressed in. The treadle operates the tuning members of both AM and FM tuners, but only one of these is in circuit at a time, according to the position of a switch attached to the bar 30 (Fig. 4, not shown). To set the tuning for a given station the button is pulled out so that arms 63 become disengaged from pieces 64 and free the cams 66, 67 for adjustment. The manual tuning knob 19 is then rotated to turn the treadle arm 42 through gearing to the required position. The button is then pushed fully in so that the cam 66 or 67 strikes the treadle and is aligned with it. At the end of the inward motion of the button the parts 63 and 64 engage once more to lock the cams. Construction of plungers.-The plunger 49 has a slot 53 (Fig. 7c) near its lower edge extended upwards by notches 56 at the front end and 58 at the middle. The plunger 50 similarly has a slot 52 near its upper edge extended downwards by notches 55 and 59. The pin 60 attached to the button slide 47 will slide freely in one slot when the button is pressed but will be located in a notch of the other to push the corresponding plunger in. Fig. 7c shows the position in which the button assembly is in its lower position where the pin 60 is in the notch 55 of plunger 50. This notch is aligned with notch 58 and the pin passes through both. (The other position of the assembly is seen in Fig. 7b, not shown). If the arm 30 should inadvertently be moved into its other position while the button is in its fully out position the pin 60 will move into the channel of the other plunger (as seen in Fig. 7c) and the wrong plunger 50 cannot be pushed in since the pin 60 will move only up to the far end of the notch 55 (Fig. 7d, not shown). Modified plungers (Fig. 9).-In this form the button is hollow and carries two pins 75, 76, one or other of which will engage a slot 80 or 81 in the plungers 78, 79 according to the vertical position of the button assembly. Each plunger carries a cam 83 (only one shown) to operate the treadle 421 attached to the tuning members.