US2346399A - Tuner - Google Patents

Description

'8. A. SCHWARZ ET AL April 11, 1944.

TUNER Filed Feb. 4, 1942 2 Sheets-Sheet l My w a. a

April 4- B. A. scHwARz ETAL. 2,345,399

TUNER Filed Feb. 4, 1942 2 Sheets-Sheet 2 a mam 8,, zldgy 4amw I Gttomeg Patented Apr. 11, 1944 TUNER Bertram A. Schwarz and Ludwig J. Fichter, Kokom0, Ind., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application February 4, 1942, Serial No. 429,442

8 Claims.

This invention relates to indexing means and more specifically to indexing mean associated with tuning apparatus for radio receivers. It has become quite common to construct radio receivers wherein by merely pressing upon either a pivoted or slidable member and actuating it over a short distance it is possible to tune a radio receiver to certain predetermined set stations in addition to the usual manual tuning knob. There are always a few radio stations to which the owner of a receiver ordinarily listens. These are of course generally the transmitters within a rather limited radius of the location in which the receiver is operated and these may be set up on automatic tuning apparatus.

It is therefore an object of our invention to provide actuatable means for automatically indexing the tuning mechanism of a radio receiver.

It is a further object of our invention to provide mechanism which may be easily reset to other stations as desired.

It is a still further object of our invention to provide tuning means which is rugged and dependable and will not jar off station.

With these and other objects in view, which will become apparent as. the specification proceeds, our invention will be best understood by reference to the following specification and claims and the illustrations in the accompanying drawings, in which:

Figure 1 is a front elevation of a tuning mechanism according to our invention;

Figure 2 i an enlarged sectional view taken on line 2-2 of Figure 1;

Figure 3 is a top plan view of the tuner of our invention;

Figure 4 is an end elevation of our invention;

Figure 5 is a sectional view taken on line 55 of Figur 6;

Figure 6 is an enlarged sectional view taken on line 6-6 of Figure 4; and

Figure 7 is a sectional view taken on line 1-1 of Figure 3.

Referring now more specifically to the drawings, there is shown in Figure 1 the front plate 2 of a tuning mechanism through which project a volume control member 4 and a manual tuning knob 6 at the left'and right hand extremities respectively and between which project a number of horizontally slidable push buttons 8 for so-called automatic tuning. The tuning mechanism is supported in a casing 10 which is in the form of a rectangular shallow box having two side plates l2 and' l4. Supported between these side plates is a treadle bar assembly composed of two horizontal rods 16 and [8 which are secured at their ends to plates 20 and 22. Plate 2|] carries a substantially cylindrical boss 24 having a central depression within which is carried a small ball bearing pivot 26 whose positionjis adjustable by a threaded member 28 in which it is carried which is supported on the side plate l2 and locked in position by a lock nut 30. The opposite plate 22 has secured rigidly thereto a short shaft 32 which extends through the side plate [4 and carries means thereon which may be manually operated to turn'the treadle assembly and will later be described.

The outer end of both plates 20 and 22 has pivoted thereto a lever arm 34 and 36 respectively, the outer ends of each being pivotally connected to a transverse rod 38. j This rod has a length greater than the distance between the two side plates [2 and I4 and the opposite ends extend through longitudinal slots 40 so that this rod may be slid longitudinally of the frame. Thus a the treadle bar rotates, the levers 34-36 cause the rod 38 to be moved longitudinally of the frame. Pivotally secured to the rod 38 at various axial points are a plurality of lugs 42to which are threadedly attached, in this instance comminuted core members 44,which cooperate with associated coils not shown per se which are located within shield cans 41. Thus, as the rod 38 moves, it in turncauses the tuning means, in this instance and for illustrative purposes only the comminuted cores, to tune the radio receiver. l i

The mechanism for adjusting the treadle bar assembly to various set positions will now be described and comprises a series of longitudinally extending shafts 46 which have the inner end extending through an opening 48 in a vertical portion 50 of the casing I 0. The forward portion of each is carried by a second vertical portion 52. An intermediate portion of the shaft 46 carries a plurality of threaded portions 54 and 58 which are adjacent each other and are threaded in opposite directions. Adjacent the inner end of the threads 58 there is mounted a washer 60 which acts as a stop for oneend of a. helical spring 62 mounted on the rods, the opposite end of which bears against the inner surface of the vertical portion 50 0f the frame. This tends to naintain a bias outwardly on each of the shafts 4 V The outer end of the threads 54 bears against a washer 64 which in turn bears against a plate 66 of sound insulating material on theinner surface of the member 52 'to'thus cause a stop in shaft. The outer end of the cylindrical member.

is knurled as at I8 and over this outer end there is adapted to be slid a hollow manual push button knob 8 which is maintained thereon :by friction and also by some spring pressure from the locking spring 10.

Carried on the threaded portion 54 of the shaft is a traveling nut 82 which extends on both sides of the shaft and has secured thereto one end of a pin 84. It also has an opening 86 therein to slidably support the end of a second pin member 86'. "Supported, on the other threaded portion 58 is a second traveling nut'SIl which slidably supports "the opposite end of'the pin 84 and rigidly supports "an intermediate'portion of thepin 86. Each of these traveling nut assemblies has a projection"92 which "extends down into a Slot 94 in the.bottom of the casing whereby these travel: ing nuts are preventedfrom rotating on the shaft but maymove axially 'thereaiong.

rhepmsai and'86' are 'so located as. to lie 'in aligmiien't with"th f treadle bars l6 and I8, the axis of the shaft '46 assing between the two treadle bars. It will thus be evident that as the shaft '46 is rotated about its own axis, the traveling nuts will move eithertoward or away from eachotherfdependingupon'the direction of rotation,fand that inv so doing the pins 84 and 86 will move with respect to each other so that they are either in alignment or one or the other is ahead and'th'us when'the shafts 46 are depressed by manual force applied to the end of the knob 8, they 'will setthe treadle bar-in a position dependent upon the position of the ends 0f the pins. This .will in turn of course setthe tuning mechanism to a similar position. .Once the pins have been-adjusted to the desired position, however, each reciprocal operation of a given knob 8 will always bring the treadle bar and tunin mechanism back to the same relative position and thus provide automatic tuning to the same radio transmitting station. In the device shown, five stations may thus-be set up, though any number may be provided. It is of course'necessary to provide also anemia means for setting the receiver at an intermediate, pint between the two limits of operation and in this case this is provided by a rotatable shaft -96 which is driven by the manual'kn'ob- 6 and drives through a flexible cable 98 a" 'worm wheel I00. This worm wheel 'I'Illl meshes with a gear I02 mounted on a collar I04 loosely mounted onthe stub shaft 32. This worm drive is irreversible and must be'disconnected when the automatic buttons are depressed .and therefore the collar and gear carry aclutch portion I'BB'which is adapted to engage a friction disc I08 which is 'rigidly connected to the shaft 32 by a set screw H 0.

The collar Ill4'ha's in its outer surface a groove H2 in which'lies a portion of 'a lever H4 which is pivoted to the frame at H6. A compression spring H8 bears against'the frame and one end of the collariI'M and tends to force it axially to maintain the Jclutch parts in engagement. The

spring may be overcome however by movement of the lever I I4 which pulls the clutch parts away from each other and disengages the clutch. The outer end of the lever I I4 is connected to one end of an L-shaped lever H6 by a resilient connection such as In, the main portion of the lever H6 lying parallel to the rear member of the casing. It is mounted by means 'of short studs H8 which :extend. through slots I20 in its surface, thus providing means whereby it may slide .-.transversely of th casing or parallel to the axis .;of the treadle bars.

There are in the surface of this lever a plurality of -angularly ;upturned portions I22 which overlie.the ends :of the reciprocating shafts 46 whichare drawn to a conical tip such as I24, thus forming a c-amming surface whereby with inward reciprocation of the shafts 46, the tip of the shaft I24 cams its associated projection I22-tocause the lever H6 to move toward the left of the tuning mechanism looking. at the same from the front,thus moving, the lever II'4 to the left about its pivot and disengaging the clutch so that the treadle bar assemmy and shaft. 32 may move without any engagementwith the irreversible worm and gear assembly of the manual drive when the automatic buttons are depressed. In order, however, to setup new station's for the push buttons which are'norm'ally operated to bring in eommomy used station's, it is necessary to provide a locking-in means so that the shaft 46 which is being reset to a new position of index maybe locked in during, the period that the operator wishes to rotate the shaft for this purpose and he will not have to hold in and turn at the same time. Normally, of course, upon merely depressing the shaft as soon asthe two pins 8-4 and 86' have forced the treadle bar around to a bottoming position, the shaft 46 is immediately returned to its outer inoperative position by the coil spring 62. However, for'resetting purposes we provide a transverse latch bar I 24 which extends across the front of the frameand lies just within the front panel. ,This bar is roughly of U-shape. and is pivoted atfits extremities I25 in the side plates I2 and I4 of the frame. It has a rear section which is stamped upwardly, asbest shown in Figure 2,'tof 'orm a raised portion I28 and the forward portion thereof is tape'red upwardly as shown. at .I'30 so that when any one of the .push buttons is depressed, the transverse bar I24 'is lifted dueto the camming action of the surface I30 with the enlarged portion 'of the member '68 on thev shaft46, As the portion. proceeds to the rear, however, it passes under the 'bar I24. If the manual knob 'B ,isin place, no locking action occurs as the upper .surface of 8 merely holds the locking barjup and the shaft is forced back out as soon as manualpressure is removed, but when the manual knob '8 is removed, the part I6 8.wi1l pass throughunder the bar and the front'fa'ce of the enlarged portion of the member 68 at I32 rides backuntil the transverse bar I24 snaps down andlOcks this member 68, and-of course the shaft 46, in its innermost position. The vertical bias on this latch bar is provided by two helical springs I34 which force the upperfaceo'f the lever downwardly and are biased against two lugs onthe frame.

When the .shaft 46being reset 'is locked thus in its inner position, the same may be rotated and in so doing of "course thetravelingfnuts 82 and 9ll are moved back and forth on, the shaft to adjust the pins 84 and 86' which are now in contact obvious that when one of the automatic $326,399 wi h the treadle bar until the desired stati n bring the tuning mechanism to any desired position. To tune the receiver to any other station than those set up on the push buttons, it is of course only necessary to manually rotate the manual knob B which is connected to the tuner at all times, except during actuation oflone of the pushbuttons. I f I In'j'order to prevent the tuning mechanism from drifting 01f station due to vibration, it will be push buttons has been actuat'e'd't'o bring the device 'to a station, as soon as it is released the clutch member will again engage the manual drive and the irreversible worm'gear will act as a locking means to maintain the t g mechanism in its adjusted position.

We claim:

1. In tuning mechanism, means for tuning a radio receiver, pivoted means extending a substantial distance on each side of its axis connected to the tuning means to move the same, a plurality of spaced reciprocable and rotatable rods supported at right angles in at least one plane to the pivoted means, each having threaded portions of opposite sign, blocks threaded on each of the portions, means to prevent the blocks from rotating, spaced abutments each of which is carried by both the blocks of each reciprocating rod which project toward and engage the pivoted means to turn the same upon reciprocation of the rod, whereby rotation of one of the rods causes relative motion between the abutments carried thereby for adjustment.

2. In tuning mechanism, means for tuning a radio receiver, means for moving said tuning means to a plurality of predetermined positions, a pivoted member for driving the moving means, a plurality of rotatable and reciprocable members movable at right angles to the axis of the pivoted member, adjustable members on each of the last mentioned members on opposite sides thereof and projecting toward the pivoted member adapted to engage and index the same whose position may be changed by rotation of the first named members, removably manually engageable means to actuate each of the plurality of members separately and independently mounted thereon, and locking means engageable with and adapted to maintain any one of the members movable at right angles at one extreme of their travel only when the manually engageable means is removed but simultaneously permit rotation for adjustment of the adjustable members.

3. In tuning mechanism, means for tuning aradio receiver, a pivoted member having substantial surface area on both sides of its axis of rotation, reciprocable and rotatable spaced rods mounted at right angles to the pivoted member in at least one plane having oppositely threaded portions, traveling nut assemblies on each threaded portion, abutments on each nut assembly projecting toward the pivoted member whereby as the rods are rotated the relative position of the abutments will be changed and index the pivoted members to a different position upon reciprocation of the rod, manual means for directly rotating the pivoted member, removable manual knobs mounted on the extendingv end of each rod, and spring biased locking means engageable with saidrods and operative only when the knob is removed to maintain the rod actuated in it innermost position.

4. 'In tuning mechanism, means for tuning a radio receiver, a pivoted member having substantial surface area on bothsides of its axis of rotation, reciprocable and rotatable spaced rods mounted at right angles to the pivoted memberhaving oppositely threaded portions, a pair of spaced traveling nuts on each rod whereby as the rod is rotated the nuts will move relatively, a pair of axially extendingpins carried in both nuts on opposite sides of each rod, said pins being alternately secured to the nuts so that relative motion between the nuts will alter the vertical alignmentof the pins, said pins extending toward andadapted to engage the pivoted member to index the tuning mechanism upon reciprocal movement of each rod and adjustable to difierent positions by rotation of each rod.

5. In tuning mechanism, means for tuning a radio receiver, a pivoted member having substantial surface area on both sides of its axis of rotation, reciprocable and rotatable spaced rods mounted at right angles to the pivoted member having oppositely threaded portions, a pair of spaced traveling nuts on each rod whereby as the rod is rotated the nuts will move relatively, a pair of axially extending pins carried in both nuts on opposite sides of each rod, said pins being alternately secured to the nuts so that relative motion between the nuts will alter the vertical alignment of the pins, said pins extending toward and adapted to engage the pivoted member to index the tuning mechanism upon reciprocal movement of each rod and adjustable to difierent positions by rotation of each rod, removable manually engageable means mounted on each rod end, and locking means to retain the rod in its innermost position when the manually engageable means is removed but inoperative to lock the rods when the manually engageable means is in position.

6. In tuning mechanism, means for tuning a radio receiver, a pivoted member having substantial surface area on both sides of its axis of rotation, reciprocable and rotatable spaced rods mounted at right angles to the pivoted member having oppositely threaded portions, a pair of spaced traveling nuts on each rodwhereby as the rod is rotated the nuts will move relatively, a pair of axially extending pins carried in both nuts on opposite sides of each rod, said pins being alternately secured to the nuts so that relative motion between the nuts will alter the vertical alignment of the pins, said pins extending toward and adapted to engage the pivoted member to index the tuning mechanism upon reciprocal movement of each rod and adjustable to diiferent positions by rotation of each rod, means for the pivoted member, clutch manual drive and the pivoted member and means actuated by the reciprocating movement of any rod to disengage the clutch means.

rods mounted at right angles to the pivoted member having oppositely threaded portions, a pair of spaced traveling nuts on each rod whereby as th'erod is rotated the nuts will move relatively, apair'of axially extending pins carried in both nuts on opposite sides of each rod,'said pins being alternately secured to the nuts so that relative motion between the nuts willalter the vertical alignment of the pins, said pins extending; toward and adapted to engage the pivoted member to index the tuning mechanism upon reciprocal movement of each rod and adjustable to different positionsby rotation ofeach rod, removable manually engageable means mounted on each rod end, lockingmeans to retain the rod in its innermost position when the manually engageable means is removed but inoperative to lock the rods when. the manually engageable means is in position, means for manually rotatmg. the pivoted. member, clutch means between the manual drive and the pivoted member and means actuated by the reciprocating movement of any rod to disengage the clutch means.

a sacgaeo 8. In tuning mechanism, means for tuning a radio receiver, means for moving said tuning means to a plurality of predetermined positions, a plurality of reciprocable and rotatable members movable toward said second-named means,

adjustable means threadedly mounted on the reciprocable means engageable with the means for moving the tuning means to cause it to tune the receiver when one of the members is recip- BERTRAM A. SCHWARZ. LUDWIG J. .FICHTER.

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