US2021476A - Radio tuning mechanism - Google Patents

Radio tuning mechanism Download PDF

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US2021476A
US2021476A US576641A US57664131A US2021476A US 2021476 A US2021476 A US 2021476A US 576641 A US576641 A US 576641A US 57664131 A US57664131 A US 57664131A US 2021476 A US2021476 A US 2021476A
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shaft
disc
stop
tuning
power
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US576641A
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Charles F Bertschinger
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HUGH J GARVEY
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HUGH J GARVEY
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    • GPHYSICS
    • G04HOROLOGY
    • G04CELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C23/00Clocks with attached or built-in means operating any device at preselected times or after preselected time-intervals

Description

R E G W H C S T R E B F c RADIO TUNING MECHANISM 5 Sheets-Sheet Filed NOV. 23, 1931 Q INVENTOR Nov. 19, 1935.
C. F. BERTSCHINGER RADIO TUNING MECHANISM 5 Shets-Sheet 2 Filed Nov. 23, 1951 INVENTOR 14/Q..% A ORNEY LAH M 5 935 N H NN Nov. 19, 1935. c. F. BERTSCHINGER 2,021,476
RADIO TUNING MECHANI SM Filed Nov. 23, 1931 5 Sheets-Sheet 3 m u WWHHWWWIlrmlmnmmmwj INVENTOR Aizn zw Nov. 19, 1935. c. F. BERTSCHINGER RADIO TUNING MECHANISM Filed Nov. 25, 1931 5 Sheets-Sheet 4 6% i/BINVENTOR ATT NEY t a 5: w
' Nov. 19, 1935. c. F. BERTSCHINGER RADIO TUNING MECHANISM Filed Nov. 23, 1931 5 Sheets-Sheet 5 A ORNEY ,JNVENTOR Patented Nov. 19, 1935 UNHTE STATES ATENT OFFICE RADIO TUNING MECHANISM Charles F. Bertschinger, Rosedale, N. Y., assignor of sixty per cent to Hugh J. Garvey, Sharpsvillc, Pa.
This invention relates to tuning mechanism for radio receiving sets and like apparatus and more particularly to automatic tuning mechanism for such purposes.
1 An object of the present invention is to provide means for automatically tuning a radio receiving set to cause the same to receive predetermined programs at predetermined times.
Another object of the invention is to provide mechanism for actuating tuning mechanism at intervals over a desired period of time.
Another object of the invention is to provide means for automatically tuning a multiplicity of radio receiving sets for receiving radiant impulses of difierent frequencies.
According to the present invention, programs may be determined in advance and by simple mechanism the radio receiving apparatus may be actuated to receive such programs according to the predetermined schedule. In order that these purposes may be accomplished the actual tuning mechanism or" the radio receiving set is arranged to be mechanically operated through the agency of power-driven apparatus, preferably operated by an electric motor. In order that the tuning mechanism be actuated at the desired intervals, use is made of a mechanical clutch for engaging the source of power with the driving mechanism of a tuning apparatus at predetermined intervals. This mechanical clutch may be operated by the same motor that furnishes power for the tuning mechanism. In conjunction with the foregoing equipment, use is made of selective equipment for determining the position of the tuning mechanism at each actuation thereof. In the simplest form of selective equipment use is made of a disc mounted on the drive shaft for the tuning apparatus, such disc having a plurality of protruding members which are positioned to lie in the path of a stop member, which stop member in turn is moved to engage various of the protruding members at various times.
More specifically the arrangement in the preferred form consists of a power supply in the nature of an electric motor, which power supply is intermittently engageable with actuating mechanism for the radio tuning apparatus through the agency of a clutch engaging the same motor or source of power. Reduction gears are utilized to cause the clutch to be moved into engaging position at stated intervals, and the same source of power also moves the selective stop to cause it to lie in the path of the rotating disc fixed to the tuning mechanism shaft so that selective protruding members will be engaged by the stop at various times. In conjunction with the radio receiving apparatus, the present invention also may be used to simultaneously tune in other receiving apparatus, such as a set for receiving waves utilized for television, etc.
Other objects, features and advantages of the present invention will be readily understood by reference to the following detail description read in conjunction with the accompanying drawings, wherein:
Figure l is a plan view of the mechanism for automatically tuning a radio receiving set to receive a predetermined schedule of programs, such receiving set having associated therewith a second receiving set for receiving radiant impulses of a different character.
Figure 2 is a front elevation of a part of the mechanism for carrying out the purposes set forth hereinbefore.
Figure 3 is an enlarged front elevation of the clutchmechanism employed in the invention.
Figure 4 is a section taken substantially on the lines 4-6 of Figure 3.
Figure 5 is a section taken substantially on the lines 55 of Figure 1, showing the arrangement of gears connecting the electric motor with the clutch actuating mechanism.
Figure 6 is a section taken substantially on the lines Efi of Figure 1.
Figure 7 is a section taken substantially on the lines 'i'! of Figure 6.
Figure 8 is an enlarged elevation of the disc utilized in selecting the programs to be received.
Figure 9 is a perspective form of an arrangement of protruding members to be secured to the disc shown in Figure 8 for aiding in the selection of programs.
Figure 10 is a section taken substantially on the lines i@l i) of Figure 9, showing the arrangement for holding the protruding members in desired position, and
Figure 11 shows a modified form of support for protruding members.
Referring now to the drawings, I0 indicates a pair of tuning condensers utilized in conjunction with other parts for tuning a radio receiving set to receive desired radiant impulses. As shown in the drawings, these condensers II] are mounted on a common shaft H, so that rotation of shaft ll causes simultaneous rotation of the rotors of the two condensers. It is to be understood, however, that the condensers must not necessarily be mounted on a common shaft but can be mounted on a plurality of shafts which can be interconnected so that rotation of one of the shafts will cause relation of all of them. Since this practice is conventional in radio receiving sets, it is deemed not necessary to illustrate the same in detail. Secured to the shaft II in front of a main supporting plate i2 is a sprocket wheel l3 engaged by a chain M, which chain is connected intermittently in a manner to be described hereinafter to cause rotation of the shaft and consequent tuning of the receiving set.
Secured to the plate E2 in a desired manner is an electrical motor i5 supplied with energy through leads it from any convenient source. This motor i5 may be any type of electrical motor, but it has been found in practice that beneficial results can be obtained when the motor is a synchronous motor. The shaft ii of motor i 5 is connected through a train of gears to a clutch actuating shaft l8, the train being of such ratio that the shaft l8 makes a complete turn once every hour. The Various gears in this train are of the usual reduction type, with the exception of the last gear 13 which is so arranged as to permit rotation of shaft i3 independently of the rotation of the gear train. For this purpose, gear it is not keyed to shaft i8 but is free for rotation thereon. The gear iELhowever, is positioned between two plates 26 and 2| which are provided with faces 22 and 23 respectively of cork or other suitable material which will ordinarily grip the gear 9 with suflicient force to cause simultaneous rotation of the gear and the plates 26 and 2 l. The hub of plate 20, as shown in Figure 4, is keyed to shaft 58 by means of a pin 24, While a spring 25 serves to force the plate 2| against the opposite side of the gear l9. With this pressure applied by the spring, rotation of gear is by means of the train of reduction gears will be communicated to the shaft iii, but at the same time this shaft 58 may be rotated independently of gear i9 since the faces 22 and 23 will permit some slipping between their surfaces and the faces of the gear.
Secured to shaft IE on the opposite side of plate 12 from the gear I9 is a clutch actuating disc 23, in theface of which are cut (in the present in stance) four slots 21. Since the shaft 18, as before stated, makes approximately one revolution per hour, and since these slots 21 are spaced equi distantly around the disc 26, it will be apparent that the slots are spaced apart approximately 15 minutes in the rotation of the shaft and disc.
In the event it is desired to receive radiant impulses for television or other purposes, simultaneously with the broadcast program selected by condensers If}, another receiving set with which the condensers IE) are associated may be employed. These condensers are mounted in the fashion similar to condensers If] on a common shaft II, which also has a sprocket wheel I3 secured thereto, over which passes a chain M.
In order that the tuning condensers of either or both receiving sets may be actuated to receive desired programs at predetermined times, use is made of a clutch arrangement for communicating power through either one or both of the chains Hi and M to the respective shafts I! and II. This clutch mechanism is shown in detail in Figure 4, wherein a shaft 33 is illustrated, such shaft being one of those contained in the train of reduction gears and being extended a distance beyond the face of plate 12. While the motor I5 is energized, this shaft 39 is being constantly rotated. Secured to shaft 30 is a disc 3| having a hub 32 fitting in an opening cut in plate 52 and serving as a bearing for the shaft relative to this plate. A
sprocket wheel 33 having faces 34 of cork or other suitable frictional substance is loosely mounted on this shaft 30. A second sprocket wheel 35 is also loosely mounted on shaft 30, such wheel being provided with faces 36 of cork or other suitable frictional material. Located between the wheels 33 and 35 is a washer-like member 31 secured to the shaft 33 for sliding engagement therealong. Adjacent the outside face of wheel 35 is a disc 38 which is also keyed to shaft 30 for sliding movement therealong. Adjacent the disc 38 is a pulley member 39 having a groove 43 cut in the peripheral surface thereof. The pulley 39 is likewise keyed to shaft 3!] for sliding movement therealong. Near the end of shaft 39 is a small washer 4| and a spring 42 is positioned between washer 4i and pulley 39 to ordinarily force this pulley 39 against the washer 38 and thereby compress the various cork faces against their contacting surfaces of other elements.
To control the pressure applied to the pulley 39 by the spring 42, use is made of a clutch bar 53, one endof which is pivotally mounted between the forks i l of a 2 bar 45, one end of which is rigidly secured to plate I 2. A pin 48 is utilized forthis pivotal mounting. lhe clutch bar 43 has an annular enlargement til fitting over the exterior of pulley 39 and pins 58 spaced diametrically opposite from eachother extendthrough the enlargement 4'? into the channel 40 of the pulley 39. The clutch bar 53 is provided with a second enlargement 53, through which shaft "I8 passes. The end of bar 431s positioned between two guide members 51 which serve merely to hold thebar in proper alignment with its pivotal mounting. Extending through bar 53 is a screw threaded plunger 52 locked in position by means of a nut 53. One end of the plunger 52 is pointed, as indicated at 5%, and this end pressed against the outside surface of the disc 25 in such fashionv that it will drop into the slots 2'! in this disc as the disc is rotated.
For selecting the various programs, use is made of a large disc 6!) removablykeyed to shaft 1 I.
A stop 6|, is provided on this shaft to aid in determining the position of the disc thereon. The disc itself is shown in detail in Figure 8, in which figure the arrangement is shown as having a slot 62 cut partially around theisame near the outer edge thereof. The outerportion of the disc is provided with a raised shoulder 63, in which are cut a number of radial grooves Bl. The periphery of the disc is marked off with a scale 55, as shown in Figure 1.
A number of stop bars 53 are adapted to be secured to the disc 'in various positions. As 55 shown in Figure 9, the preferred form of stop bar is in the nature of a long flat member hay-- inga head '51, the under side of which is pro vided with teeth es of such shape as to fit into the radial grooves at. =Mounted along the surface of the bars 35- are a number of adjustable stops 59 mounted between spacers 10. These stops $9 are rotatable through an angle of approximately 90 degrees and have a pair of depressions H and 12 at right angles to each other. A curved spring bar 73 is fastened to the under side of the bar 65 and extends around into position to bear in either of the depressions if or E2. The head iii of the bar is provided with an opening it through which a bolt i5 (Figure '7) passes, such bolt being adapted to pass through the slot 62, with the aid of a wing nut 73 looking the respective bars rigidly in place'on the disc. An alternative form of stop bar and stops is shown in Figurell, in which the bar 66 is pro- 75 vided with a number of spaced openings 11 along its length, into which removable pins 18 may be inserted. The head 61' is provided with an opening 14 for the reception of a bolt and wing nut in the same manner as that employed in the .bar 66.
Mounted in front of plate I2 is a substantially hollow rack guide 83, the under side of which is open an amount sufficient to permit the extension therethrough of the teeth 8! of rack 82.
,;,1I'hese teeth 8| are in engagement with teeth A similar disc 68' 83 on shaft l8. A part of the front of the rack guide 80 is open to permit the extension therethrough of a pin 85 on which is mounted a boss 86. Extending through the boss is a pin Bl hav .ing a right angular extension 88, which extension is movable into the path of the stops carried by the disc 60. Extending upwardly also from the rack and through the front opening thereof is a bar 90 which has a pointer 9| extending over the top of the rack guide 86 in position to cooperate with scale markings 92 on the top of the rack guide. A knob 95 is positioned on the end of shaft I8 for permitting manual rotation of this shaft.
is mounted in the same fashion on the shaft l l and corresponding parts are provided for this arrangement, these parts being given the same reference characters as those associated with shaft II, with the addition of a prime after each reference.
The operation and use of the arrangement is substantially as follows: Before the system is put into actual operation the programs to be selected over a desired period are chosen. Having in mind the number of stations in the schedule, a bar 66 is positioned on the disc 60 at such location as to correspond to the position of the condensers for that station. The scale markings 85 on the periphery of the disc aid in determining the proper location of each bar 66. Since the bars 68 extend along radial lines from the center of the disc outwardly, it will be readily apparent that each bar can serve for an individual station. .With the desired number of bars in position, the arrangement provides a number of movable stops which are in concentric circular arrangement with respect to the axis of the disc. These stops are so positioned that in conjunction with the other mechanism of the device they are located aproximately 15 minutes apart over the period in which the device is to be used. Accordingly, certain of the stops in each bar are moved into outermost position according to the time at which it is desired to receive programs broadcast by the transmitting station for which the stop'bars are set. For example, the innermost stop in one bar may be moved into operative position, the next outward stop of another bar moved into operative position, and so on around until the complete program is arranged. If it is desired to receive from one transmitting station for a longer period than 15 minutes, then consecutive stops are moved outwardly along that station stop bar. With the disc arranged according to schedule, it is adjusted on the shaft I I being lock-ed thereon by means of a set screw 96 or in any other suitable manner. The rack 82 is then moved to the right as far as the same can go, so that it is in position at the be-- ginning of its path of travel, the direction of rotation of shaft I8 in the present instance being counter-clockwise. When the rack has been moved to this position the stop 88 lies in the path of the inner most stops on the bar 66 so that when the disc 60 is rotated this stop will be con- 7 tacted by the innermost stop which is in operative position. The system is so constructed that in this arrangement the pointed end 54 of the pin 52 rests in one of the grooves 21 of disc 26. 5
soon as shaft 3!! starts rotating, the sprocket 33 will begin to rotate, due to the closing of the clutch arrangement. Rotation of sprocket 33 causes movement of chain 14, which movement is 15 I imparted to the sprocket l3, thereby rotating shaft II. This rotation continues until the selected innermost stop on one of the bars 66 comes into contact with the horizontally moving stop 88. When such contact is made, the shaft ll 20 I t can no longer rotate but the pin 52 is still seated in the groove 21, so that normally the sprocket 33 would continue to rotate. However, the provision of cork faces, or similar faces, on the sprocket 33 permits slipping between the shaft 25 3B and this sprocket, so that the sprocket may remain stationary relative to the shaft.
Continued movement of the gear train causes rotation of shaft H? with consequent rotation of disc 26. As this disc rides slowly onward, the end 54 of pin 52 rides out of the groove 21 in which it was seated and now presses against the raised shoulder on this disc. As soon as the pin rides on this raised shoulder the clutch bar 43 is moved outwardly an amount sufficient to re- 85 move the pressure from the clutch parts, so that no rotation could be imparted to the sprocket 33. The pin rides on the shoulder of the disc for approximately 15 minutes, at which time the end of the pin drops into the next groove 21, per- 4.0 mitting the clutch bar 43 to move inwardly, thereby applying compression upon the clutch parts. As soon as this takes place rotation is again imparted to the sprocket wheel 33, which rotation is transmitted to shaft H through the 46 chain I4. The shaft II then rotates until the next outward movable stop on one of the bars 66 contacts with the horizontally movable stop 88, at which point rotation of shaft ll ceases due to slipping in the clutch. This stop 88 of course 50 has been moved into the lines of the next concentric circle of stops, due to movement of rack 82 by engagement of the teeth 83 with teeth 8|. Similar operation of the mechanism continues throughout the period for which programs have been selected.
If it is desirable, the second receiving set may be operated simultaneously with the first, since corresponding parts are furnished therewith and since a sprocket wheel 35 is provided for rotation of shaft ll. Programs may be selected for this second set as well as for the first, and if the second set is utilized for receiving a television program along with the other program, these programs may be synchronized and simultaneously received.
The provision of the double sprocket wheels shown in the clutch permits continued rotation of one sprocket wheel after the other has stopped, so that if rotation of one shaft H or H is halted before the other, the other may still be moved to proper position.
A feature of the present invention is its flexibility, since it may be adapted to meet various conditions. For example, if it is desired to start 76 the set in the middle or at any point in the period for which selections have been made, the mechanism may be so adjusted. Due to the slipping between the gear [9 and shaft l8, in the manner describedin detail hereinbefore, it-is;;p0ssible to rotate'this shaft l8 manually by merely turning the knob 95. By so turning this knob the rack 82 may be moved into the path of a stop posil tioned inany of the concentric circles corresponding to the particular time over the period selected.
The desired position may be located by use of' the pointer 9! which, in cooperation with the scale 92, indicates the position of the rack and the stop 83 at all times.
Since the signals from all broadcast stations are not received at a given pointwith quick intensity, it may be necessary to arrange the system to compensate for any inequalities in volume :between various stations, so that during a given period in which a number of stations are being received consecutively, it will not be necessary to manually control the volume of any station. To accomplish this it is merely necessary when set-v ting the bars for a series of programs to shift the ,two independent receivers of radiant impulses that the invention can be employed with a single receiver or with more than two receivers. Furthermore, it will be evident that various changes can be made in the parts of the invention without departing from the spirit thereof and in view of this, it is to be understood that the invention is ,notto be limited to the illustrated embodiment but is to be limited only by the scope of the following claims.
I claim:
1. In a device of the class described, the com- ,bination of a radio receiving set having tuning mechanism to select waves to be received, a source of continuous motive power driving a timing device, a selector disc associated with said tuning mechanism, means controlled by said timing de- ,vice for intermittently connectingsaid source. of power to said disc to rotate said disc, a selector stop carried by said disc, and a movable stop driven by said source of power, said movable stop cooperating with said selector stop to selectively control said tuning mechanism when the selector stop engages the movable stop during rotation of said disc.
the path of the selector stops on said disc, said stop member being moved at a predetermined rate by said source of power, and means for intermittently transmititng power from said source to said disc for predetermined intervals to cause rotation of the disc until a selectormeans thereon engages said movable stop member, said means for transmitting power being rendered inopera-' tive to transmit power to the disc during an interval of transmission after the movable stop member has'engaged a selector stop.
3. In a device of the class described, radio 5 therewith in circular paths, and a movable stop'ls member driven in a linear path by said source of power, said stop members cooperating to control positioning of the tuning means during the'interval of connection of the source of power to the tuning means.
4. In a device of the class described, tuning mechanism to tune in predetermined radio waves for reception, power means, a clutch mechanism" operatively connecting said power means with said tuning means, timing devices driven by-said 2 power means for rendering said clutch mech'a-' nism effective at predetermined intervals, a time stop moved by said timing devices, and station selecting means comprising stops moved through the operation of said clutch mechanism for stop- 30 ping the movement of said tuning mechanism when a predetermined position thereof has been reached at a given time interval whereby a predetermined radio program is automatically selected.
5. A device of the class described compris L ing tuning mechanism to select predetermined radio waves for reception, a source of constant motive power driving a timing device, a movable stop member, driving means between said stop 40 member and said source of power for moving said stop member at a predetermined timed rate,
a wave length selector operatively connected with said tuning mechanism and having parts engageable with said moving stop member, and means for intermittently transmitting power from said source of power to said wave length selector to drive the wave length selector at predetermined intervals of predetermined length, said power transmitting means being rendered inoperative to transmit power after said moving stop member engages a cooperating member on said wave length selector.
6. The combination with the tuning mechanisms of a plurality of receivers of radiant"im'-' pulses, of a single source of continuous motive power, multiple clutch-controlled means for transmitting power from said source to said tuning mechanisms, a timing device driven by said source of continuous motive power, means associated with said timing device for intermittently actuating said multiple clutches to cause transmission of power to said tuning mechanisms to operate the same, and means for rendering any clutch inoperative to transmit power without preventing transmission of power by another clutch.
'7. The combination with the tuning mechanism of a receiver of radiant impulses, of a source of continuous motive power, clutch-controlled means for transmitting power from said source to said tuning mechanism, a timing device driven by said source, and means associated with said timing device for intermittently actuating said clutch to cause transmission of power to said tuning mechanism to operate the same, 76
means for controlling the operation of said tuning mechanism to tune the same in accordance with a predetermined schedule, and means for interrupting the transfer of power from said clutch at any time during the fixed periods of energization thereof.
8. The combination with the tuning mechanism of a receiver of radiant impulses, of a driven shaft for said tuning mechanism, a plate carried by said shaft, a plurality of stops extending from one face of said plate and spaced concentrically from said shaft, a stop member movable into the path of consecutive concentric stops, and means for supplying energy to rotate intermittently said shaft and to move continuously said stop member.
mechanism inoperative to transfer power to av tuning mechanism after said tuning mechanism is properly tuned without affecting transfer of power to another tuning mechanism.
CHARLES F. BERTSCHINGER.
US576641A 1931-11-23 1931-11-23 Radio tuning mechanism Expired - Lifetime US2021476A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2453252A (en) * 1944-12-05 1948-11-09 Rca Corp Tuning control mechanism for radio receivers
US3093183A (en) * 1958-10-01 1963-06-11 Sylvania Electric Prod Zeroing mechanism

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2453252A (en) * 1944-12-05 1948-11-09 Rca Corp Tuning control mechanism for radio receivers
US3093183A (en) * 1958-10-01 1963-06-11 Sylvania Electric Prod Zeroing mechanism

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