US2212235A - Remote automatic radio control - Google Patents

Remote automatic radio control Download PDF

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US2212235A
US2212235A US196108A US19610838A US2212235A US 2212235 A US2212235 A US 2212235A US 196108 A US196108 A US 196108A US 19610838 A US19610838 A US 19610838A US 2212235 A US2212235 A US 2212235A
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Prior art keywords
shaft
racks
tuning
pinion
motor
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US196108A
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Robert H Hill
Bertram A Schwarz
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Motors Liquidation Co
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Motors Liquidation Co
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    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03JTUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J5/00Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
    • H03J5/02Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with variable tuning element having a number of predetermined settings and adjustable to a desired one of these settings
    • H03J5/14Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with variable tuning element having a number of predetermined settings and adjustable to a desired one of these settings operated by auxiliary power
    • H03J5/22Settings determined by a number of separately actuated driving means which adjust the tuning element directly to desired settings

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Description

Aug.'20, 1940- R. H. HILL ET AL REMOTE Auwougvuc RADIO CONTROL Filed March 16, 1938 4 Sheets-Sheet l PANEL FM JPEAKE? T0 540/0 POWER SUPPLY lgweht Want an 9/112 3672mm Zi'kmtz attorney R. H. HILL ET AL 2,212,235
REMOTE AUTOMATIC RADIO CONTROL Filed March 16, l9 38 4 Sheets-Sheet 2 m fl 6 0 I- W mm l lfluwh hv l l l i a w U 1 1 i 4 Q k a MM mo o.. w@ m w w Aug. 20. 1940.
. 5 H U1 my m Miami 5 0.3 9 0 R. H. HILL ET AL I REMOTE AUTOMATIC RADIO'CONTROL -4 Sheets-Sheet 3 Filed March 16, 1938 Aug. 20, 1940. y H. H|L L ET AL 2,212,235
' REMOTE AUTOMATIC RADIO CONTROL Filed March 1a, 1938 4 Sheets-Sheei 4 lnventors Bu 9 %K l I Gttornegs Patented Aug. 20, 1940 4 PATENT OFFICE 2,212,235 v REMOTE AUTOMATIC RADIO CONTROL Robert H. Hill,
Anderson,
and Bertram A.
Schw'arz, Kokomo, Ind., assignors to General Motors Corporation, Detroit, Mich., a corpora- "tion of Delaware Application March 16, 1938, Serial No. 196,108
, 17 Claims.
This invention relates to automatic control apparatus and more specifically to means for automatically tuning a radio receiving set.
With the increased interest in the use of 5 automotive radio receiving sets and also with the increased demand for some means in a household receiving set which would either tune the set automatically from a point adjacent the set itself or from some remote point, it has been 10 found desirable to design mechanism to carry out this automatic control feature.
It is therefore the object of our invention to provide an automatic radio tuning device.
It is a further object of our invention to pro- 1 vide a remotely positioned automatic tuning device.
It is a still further object of our invention to provide an automatic remote tuning device which is simple and foolproof in its operation so that 20 it may be easily operated. g
With these and other objects in view which will become more apparent upon the disclosure of the following specification, our invention will be best understood by reference to the following 25 specification and claims which are illustrated in the accompanying drawings, in which:
Figure' 1 shows a schematic diagram of the general arrangement of our invention with relation to the radio set.
30 Figure 2 shows a wiring diagram of the circuit of our invention. I I
Figure 3 is a top plan view of the tuning device per se.
Figure 4 is a side elevation of the device shown 35 in Figure 3.
Figure 5 is a sectional view taken on line 5-5 of Figure 4.
Figure 6 is a sectional view taken on line G-G of Figure 4. I 1 40 Figures '7, 8 and 9 are views similar to Figure 6 showing the differentpositions of operation for the operating m'embers.
Figure 10 is a side elevation of one of the operating relays. Figure 11 is a top view of the same.
Figure 12 is a sectional view taken on line l2-|2 of Figure 4.
Figure 13 is an enlarged sectional detail of the mounting of the gears on the shaft. 5 Figure 14 is an enlarged detail showing one of the operating switches. Referring now more specifically to the disclosure of Figure 1, a radio receiving set designated generally at 2 is shown which is connected 155 to a cable 4 to the opposite end of which is may move vertically slightly.
connected the usual remote control panel 6 having therein a tuning knob 8, a volume control It, and a tone control i2. 1 There is also associated with the set 2 a conventional form of speaker 14 and all of the apparatus so far described forming the conven'* tional automotive set of the present day, the set being mounted on the dash of the car and the control panel being mounted on the instrument panel for access to the driver of the vehicle.
Extending from one side of the radio set is one end of the tuning shaft It to which is coupled by suitable coupling member I! the tuning device generally designated at 20 which forms the main body of our invention. Thistuning device is connected by an electric cable 22 having a plurality of wires therein to a remote control panel generally designated at 24, said panel having a plurality of push button switches 26 therein, the closure of which causes the energization of an associated magnet for tuning purposes. While this unit is shown as placed at a distance from the set, it of course may be located within the set casing if desired, as when it was used in a household set. 25
The general operation of the automatic portion of the device is such that when one of the buttons 26 is depressed the tuning motor,
switches and relays within the device 20 will be set in operation to cause the tuning shaft in the 30 radio set to be turned. to a predetermined position for the reception of a particular station, the identification of which is marked on the labels 28.
The tuning device 20 is composed of two opposite spaced panels 30 which are secured together at the bottom by plate 32. Slidably carried between the spaced panels 30 at opposite ends of the device are two irregularly shaped plates 34 which extend upwardly above the edges of the panels 30 and have adjacent their upper portion two paired oppositely disposed openings 36 within which are carried longitudinally extending rods 28. These rods extend substantially the full length of the assembly and are held in position by having a groove 40 provided adjacent each end within which its one end of a spring 42 so that the same may not be moved longitudinally from their supports but Outside of the members 34 are two end plates 44 which extend up to a slightlygreater height than the members 34 and which have adjacent the central portion an opening 46 in each end in which is carried a rod 48, the outer ends of u which are each connected to a coil spring 88 which is anchored to the plate at a suitable posltiomsuch as 52.
IBy reference to Figure 5 it will be seen that the openings 46 in these end plates are considerably larger than the diameter of the rod 48 so that there may be some relative movement of the rod in the opening which of course is biased by the springs 50 to the lowermost position of the aperture. On one side of the assembly there is provided an angled bracket 53 upon which is supported a small motor 54 which drives through its shaft 56 a suitable worm gear 58. There is supported in the assembly at right angles to the motor shaft 55 a transverse shaft 60 having on its end a worm wheel 62 which is adapted to mesh with the worm gear 58 and transfer the power of the motor into the interior of the assembly. Each of the side panels 30 carries a small upstanding bracket 84 in which the shaft 60 is journalled in any suitable bearings such as those illustrated at 88. Interiorly of the assembly on the shaft 60 is secured a gear 68 which is adapted to mesh with and drive a second gear III on a third shaft "I2 which lies substantially parallel to the motor shaft 58 and is trunnioned in two vertical plates I4 within the assembly. This shaft 12 does not extend the full length of the distances between the relatively movable plates 34 but has located on its inner end a circular plate 16 which has an eccentric projection 18 on its outer face which engages with a; circular bearing 88 which extends into a slot 8I in the rear wall 34. The gear 18 also has an eccentric projection 82 in alignment with the projection I8 which extends into a circular bear ing 84 flanged to maintain it in slot 86 in the forward plate 34.
It is thus evident that as the shaft 56 is driven by the motor the transverse shaft 60 will be rotated which will in turn drive the second longitudinal shaft 12 and rotate the gears 18 and 68 which through their eccentrics will cause the two opposite plates 34 to be moved up and down carrying the associated assembly with them including the pair of longitudinal rods 38.
Mounted within the lower portion of the assembly and running longitudinally thereof and parallel-with theshaft I2 is a further shaft 88 which is directly connected to the tuning condenser shaft of the set to which it may be connected by any convenient coupling such as 80. This shaft is also trunnioned in the same plates I4 by suitable bearings and is also supported adjacent its midpoint by a further plate 92 and has located thereon a series of gears 94, the method of mounting the latter being best shown in Figure 13 where it will be seen that the shaft hascountersunk grooves cut thereinto, such as 98, adjacent each end of each one of these gears 84 which are rotatably mounted on the shaft. There are inserted in these rings spring disks 88 which bear against the shoulders on the shaftand against the opposite faces of the gears 94 so that the same may be connected to the shaft frictionally but may have relative motion thereto where it is desired to fit them at some particular angularity with respect to the shaft for initial setting.
Supported adjacent the left end of the shaft as viewed in Figure 4 is a suitable housing I08 in which is enclosed a magnetic coil I02 which surrounds a disk I84 supported on the end of the shaft in such a manner that when the magnet is energized the disk will be locked against rotation and therefore lock the tuning shaft in that position. The purpose of this device is to allow initial setting of the mechanism to a predetermined station.
Supported on the brackets 14 and to the rear of an insulating panel I06 carried thereby are a. plurality of transversely positioned. relay coils I08; one for each station and in this instance there are six. They are each located above the associated pinion 94. Slidably supported on the side panels 30 adjacent each pinion are a pair of oppositely disposed racks I I8 and H2 which are supported in such a manner that they may move up and down as shown and in so doing will rotate the associated pinion 94 and the shaft 88. It will be seen from an examination of Figures 7, 8 and 9 that as the racks are set at different positions any pressure from the top will cause the pinion to rotate a predetermined amount until the two are leveled and in alignment and the amount of difierence may be on either side which will cause the rotation of the pinion and shaft in either direction. Therefore if we have the racks and pinion as shown in Figure 7 and pressure is applied to the upper portion of the right hand rack, the pinion will be turned until the upper portions of the two racks are parallel which will be substantially three teeth on the pinion and at the setting will give some desired station.
Carried on the longitudinal rods 38 are a plurality of spaced pivoted arms 4 which are located in pairs forming what might be termed tongs, two for each one of the magnets I08. These arms H4 are formed in the manner of a bell crank pivoted slightly off the center of the angle and having a counterbalancing heavier portion H6 to maintain them in their outward position, the inner ends I I8 being located to contact the rod 48 carried by the stationary end portions. These members of course move up and down with the movable members 34 and when in their uppermost position contact the rod 48 to cause the tongs to move apart or assume the position as shown in Figure 6. Upon an energization of one of the magnetic coils I08. the two attendant arms will be pulled together as soon as the end plates have started down and will allow such an action, and when in this position further movement of the arms downwardly causes engagement of the upper edge of one of the racks with one arm and forces the same down until the two are leveled which, due to the design of the apparatus, should be at the lowermost portion of travel of the end plates 34 which will then resume their motion in an upward direction and again come to rest in the uppermost position where the rod 48 will again force the tongs outwardly.
It may be mentioned here that the rods 38 are smaller than the openings 36 in the end plates into which they fit and since they are held downwardly by springs such as 42 they may be pressed up a short distance and this spring biasing at the bottom of the travel of the end plates assures that the racks be brought into correct alignment. Similar springs I28 are utilized upon a boss I22 on the arms 4 to prevent their swinging back and forth freely and to tend to cause them to assume the last position into which they have 'been forced, either by the magnet or the mechanical means.
Mounted on one of the stationary end plates 44 by insulating disks I20. The ends of the spring members carry switch contacts I and I32 as well as a spacing member I 04 causing a cooperation between the two sets. The contact members project to a position adjacent a slot I in the plate 44 within which slot an extending pin I00 reciprocates vertically in' synchronlsm with the rotation of the shaft 12 inasmuch as it projects from the vertically reciprocating plate 04. The object of thisswitching arrangement is to provide means for opening the speaker circuit when the automatic tuning means is energized and then causing said circuit to close when the automatic mechanism resumes its position of rest. This prevents any objectionable noise emanating from the loud speaker while the set is being tuned and it also operates a motor switch.
Figures and 11 also illustrate a suitable relay coil I40 which is mounted on an insulating member I42 and which controls the operation of a motor switch I44 which is energized in series with any one of the magnets I00 to cause the motor to be energized when a given push button is depressed, and the associated tongs are drawn together so that the rack may be leveled.
Referring now specifically to Figure 2 which shows a circuit diagram of the various portions already described, the buttons 20, 26A, 2013, etc.
are shown connected directly to one side of an incoming line I40 from any suitable source of supply. In series with each one of the buttons is one of the control magnets I08, I08A, I083, etc. The opposite side of each of the series circuit is connected to a common lead I48 which is in turn connected to the motor relay I40, the opposite side of which is connected to ground.
The main power line I46 is connected to the motor switch I44, the same also being connected directly to line I50 and thence to the motor 54 and to ground which controls the operation of the motor. Line I45 is also connected to switch I00 which is on the bracket I24, the movable or common portion of said switch being connected as shown to line I50 by a short tap line I52. The switch I32 mounted on the same bracket is connected directly to the speaker. For setting purposes there is shown a setting button I54 which is connected to incoming line I40 and also through line I55'to the magnetic lock I02 and thence to ground. v
The operation of the whole device is as followsz-Taking the device in its initial condition before any predetermined stations have been set thereon, the set is tuned manually to a desired station and then the locking switch I54 is depressed, energizing the magnet I02 to maintain the tuning shaft in that position. One of the buttons 26 is then depressed which energizes the associated magnet I00 and also the motor control magnet I40 through line I40, button 2, magnet I00, relay coil I40 to ground. This causes the switch I44 to be closed andthrough an obvious circuit the motor 54 is energized and drives through gears 50, 02, 00, and I0 the shaft I2 which reciprocates the vertically movable carriage. At the same time the magnet I00 attracts the tongs associated therewith and the tips thereof come down and force the two oppositely disposed racks III and H2 into the same vertical position, the pinion slipping on the shaft. The means then goes through the remainder of the cycle, that is, until the carriage has reached the uppermost vertical position at which point the pin I00 presses against the switch arms and breaks the switch at I 00 and then the motor is deepergized.
The two racks are now in a position as shown in Figure 6, that is, with the two upper extremities lying in the'same horizontal plane or leveled. This is repeated for each one of the buttons and of course while six are shown, any number may be supplied, dependingupon the requirements of the operator. After each one of the buttons has been set to correspond with a given station, when that button is thereafter "depressed the motor will rotate and the attendant tongs will be attracted, forcing the associated racks, which may be at any vertical height, to a leveled position. This will cause the rotation of the pinion in one direction or the other, depending upon how they were set when the button was depressed, and bring into tune the desired station. It is obvious that it is only necessary to depress the desired 'button for a short period of time until the frame begins its descent, for this closes a holding circuit for the motor through switch I30. At the same time the switch I32 is opened which causes a muting of the loud speaker, and when the frame again reaches its uppermost position the switch I02 is closed, putting the speaker back in the line and opening the motor switch I30. It might also be mentioned at this point that when the frame reaches its uppermost position the two innermost tips IIO of the bell cranks II4 contact the transverse rod 40 to insure that the tongs are in open position upon deenergization so that if the associated magnet is not energized during the next operation the tongs will not contact that particular rack.
We claim:
1. In control mechanism, a rotatable shaft which it is desired to index at different angular positions, a plurality of axially spaced frictionally mounted pinions on the shaft, a plurality of reciprocable racks engaging said pinions to rotate the same, reciprocable means for driving the racks, and selective means for operating only one of the racks and pinion devices at a time.
2. In control mechanism, a rotatable shaft which it is desired to index at diiferent angular positions, a plurality of axially spaced pinions frictionally mounted on the shaft, 9, pair of oppositely disposed reciprocable racks engaging each to rotate the shaft in either direction, depending upon which of the racks is moved, and
means for selectively reciprocating the racks to drive a desired pinion for indexing the shaft.
3. In control mechanism, a rotatable shaft which it is desired to index at different angular positions, a plurality of axially spaced pinions frictionally mounted on the shaft, a pair of oppositely disposed reciprocable racks engaging each pinion to rotate it in either direction, depending upon which rack is moved, members mounted to engage the racks normally biased out of alignment therewith, magnetic means for bringing the engaging means into alignment,
means to reciprocate the engaging means and means for selectively energizing the desired magnetic means for a particular angular selection.
4. In a. control mechanism for tuning a radio receiving set, a shaft upon which the tuning .means are mounted and which it is desired to and magnetic control means for bringing into ensagement the one selected rack.
5. In a tuning control mechanism for a radio receiving set, a tuning shaft that it is desired to index at different points, a plurality of pinions axially spaced on the shaft, means for driving each pinion in either direction to rotate the shaft,
magnetic means for selecting which pinion is to be driven and a control panel connected to the magnetic means.
6. In an automatic tuning mechanism for a radio receiving set, a tuning shaft, a plurality of pinions mounted in spaced relation on the shaft, a plurality of racks oppositely disposed for each pinion which normally are set with their ends extending to different distances, means for each pair of racks which may be aligned therewith to force the farthest extending rack until the other rack is engaged to level thepair engaging one pinion which will therefore set the shaft in a given position, magnetic means for causing the alignment and a pluralitysof selectable switches to cause energization of the desired magnetic means.
'7. In an automatic timing mechanism for a radio receiving set, a tuning shaft, a plurality of axially spaced pinions on the shaft, 9. pair of reciprocating racks for driving each pinion, a motor for driving the reciprocating racks, magnetic means for causing only one set of racks to drive and switch means to select which of the magnetiemeans is to be energized.
8. In an automatic control system for-tuning a "radio receiving set, a tuning shaft, a motor for rotating said tuning shaft, reciprocating means operated by the motor for turning the shaft, a switch to control initial motor energization and a holding switch actuated by reciprocation of the means to carry the mechanism through a complete cycle. I g
9. In an automatic control system for tuning a radio receiving set, a tuning shaft, a plurality of axially spaced pinions frictionally mounted onthe shaft, reciprocable racks for driving the pinions different distances, locking means for preventing shaft rotation while the pinions. are initially set on the shaft, and motor means for driving the reciprocating means to time or set the pinions.
10. In an automatic tuning mechanism for a radio receiving set, a tuning shaft, a plurality of axially spaced pinions mounted on the shaft, a.
pair of reciprocable racks meshing with each pinion, a pair of reciprocable spring biased pivoted arms normally out of alignment with the rack movement and cooperating therewith, means to reciprocate the arms, means to bring the arms into alignment with the racks and remote control means to actuate the last named means.
11. 'In a control mechanism, a frame, a shaft rotatablymounted in the frame, a plurality of axially spaced pinions mounted on the shaft, a pair of racks mounted in the frame for reciprocal movement meshing with opposite sides of each pinion, a sub-frame mounted within the frame and movable with respect thereto in alignment with the movement of the racks, means carried by the sub-frame normally out of alignment with the racks but capable of being moved into alignment, and selective means for energizing said means to operate a desired set of racks.
12. In a control mechanism, a pair of relaamazes tively movableframes, a rotatable shaft carried by one of the frames, a plurality of axially spaced driving means mounted on said shaft, a plurality of reciprocable means associated with each driving means, means carried by the second frame to selectively engage or pass the reciprocable means upon relative motion of the two frames and means to control the selective means.
132 In a control mechanism pair of relatively movable frames, onewithin the confines of the other, a rotatable shaft carried by one frame, spaced pinions on the shaft, reciprocable racks carried by the same frame and meshing with the pinions, pivoted arms carried by the second frame adapted to engage or pass the ends of the racks upon relative movement of the frames, spring means to maintain said arms in one position, magnetic means to move said arms to engaging position and remote switching means to selectively energize the magnetic means;
14. In a control mechanism, a pair of relatively movable frames, one within the confines of the other, a rotatable shaft carried by one frame, spaced pinions on the shaft, reciprocable racks carried by the same frame and meshing with the pinions, pivoted arms carried by the second frame adapted to engage or pass the ends of the racks upon relative movement of the frames, spring means to maintain said arms in one position, magnetic means to move said arms to engaging position, counterbalancing means on the arms to assist the spring force and remote switching means to selectively energize themagnetic means.
15. In a control mechanism, a frame, a shaft rotatably mounted in the frame, a plurality of axially spaced pinions mounted on the shaft, a pair of reciprocable racks mounted in the frame meshing with each pinion, a pair of spring biased tongs mounted adjacent one end of each pair of racks and adapted to engage the rack ends when in the proper position, a common mounting for all of the tongs, means to reciprocate the mounting in the direction of the length of the racks and magnetic means for each pair of tongs to act against the spring pressure and move the tongs to engage the rack ends and level any desired rack pair.
16. In a control device, a rotatable shaft which it is desired to index to a plurality of desired positions, a plurality of axially spaced pinions mounted on the shaft, a pair of reciprocable racks for each pinion mounted to mesh with diametrically opposite sides thereof, reciprocable means to engage the ends of both racks in a pair and to force the two into alignment whereby the advancing rack acts as a stop to define an index for said shaft.
1'7. In a control mechanism, a rotatable shaft which it is desired to index to a plurality of angular positions, a plurality of axially spaced pinions frictionally mounted on the shaft, a pair of reciprocable racks for each pinion mounted to mesh with diametrically opposite sides thereof, a plurality of means adapted to selectively engage the ends of each pair of racks, a mount for the last named means, means for reciprocating the mount and means to select one of the first named means for engaging a pair of racks.
ROBERT H. HILL. BERTRAM A. SCHWARZ.
US196108A 1938-03-16 1938-03-16 Remote automatic radio control Expired - Lifetime US2212235A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2490619A (en) * 1943-12-27 1949-12-06 Rca Corp Selector mechanism for radio apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2490619A (en) * 1943-12-27 1949-12-06 Rca Corp Selector mechanism for radio apparatus

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