US2316776A

US2316776A - Electrical control apparatus

Info

Publication number: US2316776A
Application number: US357745A
Authority: US
Inventors: Harold F Elliott
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-09-21
Filing date: 1940-09-21
Publication date: 1943-04-20
Anticipated expiration: 1960-04-20

Description

April 20, 1943. H. F. ELLIOTT ELECTRICAL CONTROL APPARATUS Filed Sept. 21, 1940 4 Sheets-Sheet 1 A. H\ Hm W p y W WW/ fiwm w jya'ro/a ff/zzia/t April 20, 1943. 1 H. F. ELLIOTT ELECTRICAL CONTROL APPARATUS Filed Sept. 21, 1940 4 Sheets-Sheet 2 fizro/a ifz'az i April 20, 1943. H, F. ELLIOTT 2,316,776

ELECTRICAL CONTROL APPARATUS Filed Sept. 21, 1940 4 Sheets-Sheet 3 April H. F. ELLIOTT 3 2,316,776

ELECTRICAL CONTROL APPARATUS Filed Se pt. 21, 1940 -4. Sheets-Sheet 4 Patented Apr. 20, 1943 UNITED STATES PATENT OFFICE ELECTRICAL CONTROL APPARATUS Harold F. Elliott, Pam Alto, Calif. Application September 21, 1940, Serial No. 357,745

20 Claims.

This invention relates to electrical control apparatus and in particular to an electrical tuning system for radio receiving apparatus. I

It is an object of this invention to provide an improved electrical tuning system for radio receiving apparatus.

A further object of this invention is to'provide a tuning device having normally manually actuated selector units in which such units are electrically operated by compact mechanism which is simple and rugged in construction, and efficient and quiet in operation.

Yet another object of this invention is to provide an electrical tuning device embodying a rotary control shaft which is driven to predetemined control positions by electrically operated linearly movable selector units.

A feature of this invention is found in the provision of electrical tuning apparatus embodying linearly movable operatingv members in which actuating magnets are utilized to provide atrip action for mechanically engaging the operating members. I

Another featur is found in the provision of electrical control apparatus in which a rotary control shaft is rotated in either direction of rotation by linearly movable operating members driven by a solenoid or an A. C. or D. C. unidirectional motor.

A' further feature of this invention is found in the provision of an electrical tuning device 9-9 in Fig. 8;

' Fig. 10 is a fragmentary sectional'view as seen along the line l0l0 in Fig. 8; v

Fig. 11 is a sectional view of another modified form of the invention. and r Fig. 12 is a fragmentary plan view as seen along the line "-42 in Fig. 11.

Referring to the drawings similar numbers throughout the several views shall designate similar parts. In Figs. 1 and 2 the tuning or preselector unit includes an inner frame 20 of substantially rectangular shape supported on the main frame end plates 2! and 22. A condenser shaft 23 is rotatably supported in the end plates embodying a rotary control shaft in which a plurality of linearly movable selector units hav ing a common electrical driving means are operated by selectively actuated control means.

20a and 20b of the frame 20, the condenser 24 being illustrated as of gang type with eachcondenser section thereof being electrically associated with a trimmer condenser 26. It is to be understood, however, that other frequency,

changing means may be satisfactorily used. The

1 condenser 24 is rotated to its tuning positions by Yet another feature of this invention is found in the provision of electrical tuning apparatus embodying a rotary control shaft in which a plurality of selector units are driven by a common driving gear. Each unit includes linearly movable operating and actuating portions, with the actuating portion being operable as a'clutch element and arranged to selectivelyengage the f driving gear to provide for the operation of the selector unit.

Further objects, features and advantages of this invention will become apparent from the following description when taken in connection with the accompanying drawings in which:

Fig. 1 is a fragmentary plan view of one' embodiment of the invention;

a treadle bar 21 which is likewise rotatably supported in the end plates 20a and 20b, operative connection therebetween being made through a split gear 28 mounted on the condenser shaft 23 and a gear segment 29 mounted on the treadle bar'2l. Bar 21 is of flat substantially rectangular shape having axially extending parallel portions 3| and 3| with axially spaced apertures 32 formed therebetween. Extending through each aperture 32 is a projecting finger 33 of an operating member 34, which forms part of a Fig. 2 is a sectional view as seen along the line 2-2 in Fig. 1;

Fig. 3 is a control circuit for the-embodiment of Fi 1;

selector unit 36.

the aperture 32 by

longitudinal frame members

31 and 38 which are supported in the end plates 20a and 20b.

As is clearly indicated in Fig. 1 the operating member 34 is of substantially flat form and is provided at one end with a laterally bent portion 39, for a purpose to be later described. Substantially intermediate the ends of the member 34, and to the right of the treadle bar 21 as viewed The operating member 34 is 'slidably supported for linear motion through in Fig. 2, is an adjustable element 4|- of substantially semi-circular shape and pivotally supported on the member 34 at 42. Element 4| is frictionally locked in an adjusted position by a clamping member 43 which is pivotally or hingedly connected to a laterally extending portion 44, which is bumped out of the operating member 34. The lateral extension 44 is provided with a threaded aperture for engagement with an adjusting screw 45, which has an end portion engageable with the clamping member 43 to urge the clamp into frictional engagement with the adjustable element 4| in an obvious manner.

With the element 4| in an adjusted position and with the operating member 34 and treadle bar or control shaft 21 in the relative positions indicated in Fig. 2, movement of the operating member 34 to the left moves the finger portion 33 through the aperture 32 until engagement is made between the treadle portion 3| and the end portion 46' of the element 4|. Since the element 4| is in its locked position continued movement of the operating member 34 rotates the treadle bar 21 in a clockwise direction, as viewed in Fig. 2, until engagement, is also made between the treadle bar portion 3| and the element portion 46, whereby to lock the operating member 34 against further linear movement. This engagement between the corresponding portions 3| and 46', and 3| and 46 on the treadle bar 21 and adjustable cam 4|, respectively, designates the tuned or home position of the selector unit 36, as will be later fully described. The operating member 34 is returned to its rest or idle position, indicated in Fig. 2, by a spring 41 which is positioned about the finger portion 33 and arranged in compression between the longitudinal frame member 31 and the shoulder portion 48. This rest position of the operating member is defined by the engagement of the projection 49 thereon with the frame member 36. It is to be understood, of

course, that the treadle bar 21 may be rotated shaft and element 4| are first engaged.

The operating or carriage member 34 is moved to its shaft operating position, as above described, by a linearly movable actuating member 5| which is of flat form and of substantially L-shape. The leg portion 52 of member 5| is engageable with the laterally bent portion 39 of the operating member while the leg or clutch portion 53 of the member 5| is slidably supported in a frame member 54 of substantially U-shape, but pivotally movable therein to provide for the engagement and disengagement of the clutch portion 53 with an elongated driving pinion 56. Pinion-56 is rotatably supported in the end plates 2| and 22 and is common to all of the selector units 36;

Driving of the pinion is accomplished by a motor 51 through a suitable gear train 58. The motor 51 may be either A. C. or D. C. and is uni-directional in rotation. In one commercial embodiment of the invention a solenoid instead of the motor 51, is used to drive the pinion 56.

Member 5| is normally held out of an engaged position with the pinion 56 and operating member 34 by a coil spring 59 which is connected at one end to the leg portion 52 and at its opposite end to a frame or finger portion 60, which is secured to a supporting bracket 6| for a plurality of magnets 62,. one of which is provided for each of the selector or control units 36. The bracket member 6| is mounted on the end plates 2| and 22;

. ating member 34.

the lower end of each finger 63, asviewed 2, depending therefrom and being formed'with'a notch or recess 63 for guiding the movement of the actuating .member5 An armature 64 for each magnet 62 is pivotally supported in a dovetailed engagement between the bracket 6| and lateral projections 60' on each finger 60, to provide for its tripping the member 5| into meshing engagement with the rotary member or pinion 56 on its movement to an attracted or closed position. It is contemplated that the armature 64 be comprised of a pair of longitudinally offset pieces having a fiat spring 66 arranged therebetween and extending longitudinally therefrom for engagement with the member 5| near the leg portion 52. This flexible structure of the armature 64 assures a positive and flush contact of the armature portion 61 with the magnet pole face 68 regardless of the relative positions of the teeth on the rack 53 and pinion 56. The open position of the armature 64 is limited by the cushioned stop or bumper portion 63 on the frame member 54, which is arranged to provide for a free pivotal movement of the member 5| from its meshed engagement with the driving pinion 56.

The operation of the armature 64 and the actuating member 5| is best understood from the circuit diagram of Fig. 3, in which the magnets 62 are illustrated as being connected in parallel between conductors 1| and 12 and in series connection with the motor 51, the power for the circuit being supplied from source 14. It is thus seen that on closing of a push-button 13, which push buttons may be mounted on the radio receiving apparatus or remotely therefrom, a magnet 62 and the motor 51 are concurrently energized. Let it be assumed that the armature 64 is in its rest position against the bumper 63 with the clutch portion 53 of the actuating member 5| disengaged from the driving pinion 56 by virtue of the action of the spring 59. At this position of the armature the tension of the spring 53 is such as to always pull the member 5| away from the operating member 34 and into abutting engagement with the member 54 at the projection 16. Since closing of a push button 13 concurrently energizes the corresponding magnet 62 and the driving motor 51 the gear 56 is rotated substantially simultaneously with a movement of the armature 64 to its attracted or closed position. This movement of the armature 64, by virtue of the engagement of the spring portion 66 with the actuating member 5|, moves the clutch portion 53 into engagement with the driving gear 56 against the pressure of the spring 59. Immediately upon engagement of the mem-' ber 5| and gear 56, the member 5| is moved to the left, as viewed in Fig. 2, to engage the leg portion 52 with the bent portion 39 of the oper- Since the spring 59 acts to always return the member 5| to an innermost position relative to the frame member 54, the member 5| is linearly movable to an extent corresponding to the length of the clutch portion 53. The movement of the actuating or pusher member 5| is thus always sufficient to provide for a complete engagement of the pair of corresponding portions 46 and 3|, and 46' and 3|, on the cam 4| and treadle bar 21, respectively, which engagement represents the home or tuned position of the selector unit 36 as was above fully described. On completion of the tuning operation and release of the push button 13, the operating member 34 is returned to its rest position by the spring 41, as was previously explained, and the actuatingmember 6| is lifted out of engagement with the driving pinion 68 and moved to its rest position by the spring 69. The selector unit 36 isthus in its rest or idle position so as to be ready for operation upon any later actuation of the push button I3 corresponding to such unit.

In the adjustment of the cam H to anadjusted position, the adjusting screw 46 is retracted to relieve the pressure on clamp 43 to permita free rotation of the cam 4|. The condenser 24 is then rotated by manual tuning means (not shown) to a predetermined tuning position, which may be indicated by suitable tuning indicia (not shown). With the condenser held in its tuned position the push button I3 is actuated to operate the selector\ unit 36. This operation of the unit 36 engages the corresponding engaging portions 3I' and 46', and 3| and 46, it being understood, of course, that the treadle bar 2! is stationary and that engagement occurs by virtue of the free rotation of the cam 4|.

connected to the bracket 82. The rest position oi. the armature is defined by itsengagement with pins IOI, one of which is mounted in each 01' the end plates 2| and 22'. Another spring I02 is connected at one end to the lower end of the armature, while its opposite end is connectedto the clutch element or lever 89. It is seen, therefore, that the pressure of the spring I02 acts to normally retain the lever 89 in a substantially horizontal position and in engagement with the top side I03of the aperture 88. Energization of the magnet 83 to attract the armature 96 to its'closed position thus linearly moves the arm 89 in a horizontal plane which is above the upper level of the operating member 84, and hence completely clear of the shoulder portion 92. However, the projection I8 on the actuating member 6| is normally in engagement with the bent end 93 or the lever 89 while the lever 89 is of a length to extend over the shoulder portion 92. Thus,

when the lever 6| is manually pushed toward the right the lever, by virtue of its pivotal support on the armature 96, is tripped downward With the push button held in its closed position,

the adjusting screw 45 is tightened to move the clamp 43 into frictional locking engagement with the cam 4|. Cam H is thus locked'in its adjusted position so that the condensed 24 will always be returned to such predetermined tuned position on later operation of the actuating unit 36. Y

In the modified form of the'invention shown in Figs. 410, inclusive, the operating memberas indicated in Fig. 5, until it engages the shoulder.92 of the operating member 34 for a purpose nowto be explained.

With reference-to Fig. 6 the switch 84 is indicated as' being normally open and arranged between conductors I04 and I04, and in series connection with the magnet 83, which is connected between conductors I04 and I06. -Since it is contemplated that the embodiment of Figs. 4 to 34, treadle bar 21, and condenser 24 are similar in construction and operation to the same parts as described in connection with Figs. 1 and 2, and their further explanation is, therefore, believed to be unnecessary. With reference to Figs.

4 and 5 the actuating or push rod member 5| l0,;inclusive, be adaptable particularly to farm and automobile receiving sets, the electrical energy-for the circuit is supplied from a battery I01, which is connected between the conductors is of flat form and comprised of a body portion I! having a transversely extending projection I8 and a longitudinally extending finger portion 19, which is engageable with the bent portion '39 on the operating member 34. Member 6| is I04" and I06. With the parts in their relative positions shown in Fig. 4, a manual pushing on the push rod 6| toward the right trips the push lever 89 into an engaging position with the shoulder 92 substantially concurrently with a closing of the switch 84 by the engagement of the cam portion 81 with the gate member 88. It is conslidably supported for linear movement toward the treadle bar 21 in a frame member 8| and a.

mounting bracket member 82 for a magnet 83 which is common to all of the selector units 36'. The bracket 82 is of substantially U-shape and is mounted in the end plates 2| and 22'. A normally opened spring switch 84,- common to all of the units 36, is assembled at the lower end of the bracket 82 and includes a contact blade or gate member 86 which is arranged in the path of movement of all the members 5|. The gate 86 is engageable with a cam portion 81 on each actuating member to close the switch and hence energize the magnet 83, as will be explained.

An aperture 88 is formed in the bracket 82 substantially intermediate its sides and above the finger portion I9 of the member 5|, the lower side .9I oi the aperture being in substantial horizontal I alignment with a shoulderportion 92 formed on the operating member 34 adjacent the bent en-.

gaging portion 39. Extending through the aperture 88 is a pusher or clutch member 89, which is of substantially L-shaped and pivotally supported near its bent end 93 at 94 to an armature templated that the member 5| be manually pushed and in engagement with the member 34 at the finger portion I9 until completion of the tuning operation so that the lever 89 is always held in its engaging position with the operating member 34; Energization oi the magnet 83, there fore, attracts the armature or gate member 96 to actuate the lever 89 to push the member 34 into engagement with the treadle bar'2l. It is thus seen that the electrical push of the lever 89 on the member 34 aids-the manual push of the push rod 5| to move the operating member 34. In this manner the operating member 34 is moved from its position indicated in Fig. 4 to its engaging position with the treadle bar 21, as shown in Fig. 5, which position represents the home or tuned position of the selector unit 36'.

On release of the actuating member 5| the operating member 34 is returned to its rest position by the spring 41, as was above fully explained in connection with Fig. 2. The actuating member 5I' is returned to its rest position by the spring H2 which is arranged in compression 0 between the bracket member 82 and a projection or gate member 98 for the magnet 83. Armature 96 is pivotally supported at each end thereof, in the end plates 2| and 22' as at 91, and is common to all of the selector units 36'. An angular bracket 98 secured near the upper end oi. the

armature is connected to one end of a spring 99,.

which retains the armature in its rest or open position, the opposite end of the spring 99 being .I IS-iormed on the body portion 11. Lever 89 is immediately returned to its horizontal position against the side I83 of the aperture 88 by the spring I 82 and the armature 96 is returned to its open position by the action of the spring 99.

Althoughthe magnet 83 and armature 96 are common to all of the selector units 36' it is to be noted that only the particular unit 36' being actuated operates to move the treadle bar 21.

This is accomplished by virtue of the assembly of the lever 39, which permits the lever]! to member 34 is thus not. engaged either. by the finger portion I3 of theactuat in ember 6| or by the trip lever 83 so that it is positively'ret-ained in its rest position.

It is to be understood that a magnetand armature may be provided for each of the selector units 36' to move the lever 83. A switch 64 would thus be used with each unit, with: each. switchl and its associated magnet being connected in;

series, but in parallel between conductors IIl 4 and I06 relative to the other corresponding-magnets j and switches.

the operating member 34, as indicated by the dotted lines. This tripping action is accomplished of the switch 34 energizes the solenoids to attract '"the movable elements I I3to their operated positi'ons. By virtue of the shoulder 42: formed on each member 33, the lever portion I I4a, after its 1 engagement with the shoulder 32', is engaged I ith the gate member 96 so that the pull of the plungers H9 is effective in pushing the member =63 which in turn pushes the operating member 534 into engagement with the treadle bar 21.

- is to be understood, of course, that the gate In Figs. 7, 8, 9, and 10 the gate member 36- is illustrated as being movable by a pair of solenoids II3, which are arranged at opposite; ends of the gate member. Each operating member 34 and actuating member 5 I apart from-being vertically member 96" is also pushed by the plunger II by virtue of the relative engagement between the projection .16, lever portion I I4 and gate member 36.

On completion of the tuning operation, that is.

after the treadle bar '21 has been turned to its predetermined control position by its engagement is; returned to its rest position by the spring 41 I and the gatemember 36 and solenoid plunger spaced relative to each other, aresimilar inall other respects to the operating and actuatingmembers described in Figs. 4 and 5 and, there.-

fore, will not be further explained. The gatetrip or clutch members 89' of substantially right angle shape, one of which is. provided foreach' of the units 36a. through the gate member 96 in a manner to have a depending portion II4 thereof in engagement with the projection I6 of the operating member SI. 10) is formed with an aperture I I6 corresponding to each solenoid I I3. A movable plunger or core element I I9 for each solenoid I I3 extends throughthe aperture II8, the enlarged end I2I thereof being engageable with the gate member 96' at the aperture H8. The gate is thus pulled toward the right, as viewed in Figs. 9 and 10 on energization of the solenoids II3, as will be later ex pulling action of the spring I22.

'assure a movement of the lever 83' out of an engaging position with the shoulder portion 92'.

spring II2.

'tained in a neutral position by the spring I26 Each member 89' extends The pivoted gate member 96 (Figs. 8 and V plained. As indicated in Fig. 10 each element H9 and the gate member 96 are held in their idle or rest positions by tension springs I22 which Q are connected at one end to pins I23 mounted in the end plates 2| and 22, and at their opposite ends to the gate member. This rest position is indicated by the engagement ofthe element end 6. The solenoids II3 are arranged in parallel between conductors I04 and I36 and in series with the switch 84. Thus with the parts arranged in the position shown in full lines in Fig.

9, manual pressure on the actuating member II- to move it linearly toward the right, substantially concurrently closes the switch 84 and trips the lever portion I I4a of the clutch member II4 into an engaging position with the shoulder 32' on As was previously explained, the actuating member SI is returned to its idle position by the Since the clutch member 89' is reuntil tripped by the actuating member 6|, it is readily apparent that only the selector unit 36a, which is operated is effective in driving the rotary control shaft 21 to a predetermined control position. It is readily apparent also that a solenoid H3 and switch 64 may be provided for each of the units 3611.

The modified form of the invention shown in Figs. 11 and 12 includes end plates I 21 having a condenser I26 rotatably supported thereon.

The condenser shaft I29 is provided with a gear I3I which is in meshing engagement with a gear I32 mounted on a rotary control shaft I33 having oppositely arranged flat portions formed thereon, the shaft I33 being likewise supported in the end plates I21. A plurality of adjustable control units I34 (only oneof which is shown), one for each of the selector units 363 are mounted axially of the shaft I33. Each unit I34 includes a pair of spaced gears or toothed members I36 l and I36, an adjustable or center washer I31 arranged between such gears, and a washer element I38 and I38 positioned between the adjustable washer I31 and each gear I36 and I36. Each gear I36 and I36 and a corresponding washer I36 and I36, respectively, are freely ro-,

tatable on a bushing I33a mounted on the shaft I33; with two bushings being included in each control unit I34. The bore of the bushing I330 is formed withflats corresponding to the flat portions on the shaft so as to lock the bushing for rotation with .the shaft but permitting movement thereof axially of the shaft. The gears and washers I38 and I38 are provided on the periphery thereof with axially extendingears I33 and I39 and I and HI, respectively. The adjustable element I31 is freely rotatable on the shaft I33 and is normally frictionally held between the bushings I33a in a fixed position relative to the shaft. A radially extending ear I42 is formed on the element I31, for a purpose to be explained.

Each gear I36 and I38 is in continuous meshing engagement with an operating or carriage member I 43 having a substantially U-shape portion I44'and an actuating or clutch portion I46 of gear rack form. The legs I41 and I48 of the portion I44 are parallel but laterally offset from each other as is clearly indicated in Fig. 12. Thus with the portion I44 in a straddling position relative to a control unit I34, leg portion I48 engages the gear I36 and the leg I 41 engages the gear I36, the legs I41 and I48 being of rack or toothed form along their inner facing sides. The operating member I43 is slidably supported for linear movement in frame members I49 and II, but is adapted tobe pivotally moved about the shaft I33, as will be later explained. ,Thus with the .member I43 in its position indicated in Fig. 11,

linear movement toward the left thereof rotates the gears I36 and I 36 in opposite directions. As the gears rotate ear I39 of the gear I36 engages the ear I42 of the washer I38, and the ear I39 of the gear I36 engages the ear .I4I' of the washer I38, to in turn rotate the washers I38 and I 38 in relative opposite directions. It is apparent, therefore, that the washer ears I M and MI engage opposite sides of the ear I42 of the adjustable element I31, whereby to lock thegears I38 and I36 against any further rotation. This locked position of the control unit I34 represents the predetermined control position of the shaft I33 or tuned position of the condenser I28. Since the washers I38 and I38 are not concurrently engageable with the element I 31,,it is obvious that the direction of rotation ofthe shaft I33 to its control position is dependent upon which washer I38 or I38 first engages the element I31.

Movement of the operating member I43 to rotate the shaft I 33 to a predetermined control position, as above described, is accomplished by means including an elongated pinion or rotary driving member 56 which is in driven engagement with a motor 51, of uni-directional type, through gear I 56, fibre gear I51 and reduction gears I58 and I59. Pinion 56 is common to all of the selector units 36b and is rotatably supported in the end plates I21. The clutch portion I46 of the member I43 is selectively engageable with the pinion 56 to linearly move the carriage member I43 to drive the shaft I33, but is normally retained out of an engaging position with the pinion by a spring I52. Spring I52 is connected at oneend to a projecting ear I6I on the member I 43 and at its opposite end to a mounting bracket I62 for a plurality of magnets 62, one 01 which is provided for each unit 86b. The brackei I62 also carries the frame member I 5I which guides and supports the operating member 143. Sincethe supports I 49 and ISI for the operating member I43 permit pivotal movement of such member, the portion I46 is readily lifted out of engagement with the pinion 56 when the unit 36b is in its rest position; the spring acting also on completion of the tuning operation to return or pull the member I43 into its rest position in engagement against the frame member I5I.

An armature 64 for the magnet 62 is pivotally supported on the frame member I5I and includes a flexible spring portion 66 which is engageable with the clutch or actuating portion I46 on energization of the magnet, On energization of ill the magnet 62 the armature 64' opposes the action of the spring I52 and moves the portion I46 into meshing engagement with the pinion 58 to linearly move the operating member I43. This engagement of the clutch portion I46 and the pinion 56 immediately on closing of the armature is indicated in Fig. 11. The spring 66 assures a positive contact between the armature portion 61 and the magnet pole face 68 so that the meshing engagement is maintained at all times when the magnet 62 is energized. Since the motor 51 and magnet 62 are connected in series member I43 is immediately moved linearly to the left, as viewed in Fig. 11, whereby to drive the shaft I33 to its predetermined control position, the circuit for the motor 51 and magnet 62 and its operation being similar in all respects to that previously described in Fig. 3, in connection with Figs. 1 and 2. On completion of the tuning operation and the release of a pushbutton 13 the operating member I43 is returned to its rest position by the spring I62, the lifting of the clutch portion I46 by the spring in turn lifting the spring portion 66 to move the armature portion 61' out of engagement with the pole face 68, so that the unit 3612 is ready to repeat the tuning operation on a later actuation of the push button 13. It is apparent, of course, that the movement of the carriage member I43 to the right, as viewed in Fig. 11, breaks the locked engagement of the gears I 36 and I36 with the adjustable element I31 to permit their free relative rotation on the shaft I33.

To adjust the various units I34 to a predetermined control position for the adjustable element I 31, suitable thrust mechanism (not shown) is provided on the shaft I 33, which is operable normally to frictionally lock the element I31 between each pair of bushings I 33a in fixed positions relative to the shaft I33. With the thrust mechanism in its released position the condenser I28 is adjusted to a desired tuning position by a suitable manual control knob (not shown), which is in operative engagement with the condenser shaft I29. A unit I34 is then operated to its locked position by pushing a button 13, while the operator holds the manual con-' trol knob and hence the shaft I29 from turning. The member I31 is thus adjusted to a predetermined control position for the shaft I33. A similar procedure is repeated for the other control units I34. During this setting operation, the members I 31 are maintained in adjustment by virtue of the fact that their frictional engagement with the bushings I33a as effected by the thrust mechanism is sufficient to maintain their relative positions on the shaft I33. When all of the units I 34 have been adjusted the thrust mechanism is tightened whereby to frictionally look all of the members I31 in fixed positions relative to the shaft I33.

It is to, be understood that only preferred embodiments of the invention have been illustrated and described herein and that modifications and alterations thereof can be made which are within the full intended scope of the invention as defined by the appended claims.

I claim:

1. In a radio tuning apparatus having rotary control means, a selector unit for rotating said control means to a predetermined control positicn and. including an actuator portion and an operator portion, adjustable means operatively connected with said operator portion and movable thereby into operating position with said rotary control means, electrical means for driving said selector unit, spring-pressed means connected to said actuator portion, said latter means on movement thereof in one direction cooperating with said actuator portion to operatively connect said operator portion and electrical means, and means for moving said spring-pressed means in said one direction substantially concurrently with the energization of said electrical means.

2. In radio tuning apparatus having rotary control means and manually actuated selector units for normally driving the rotary control means to a predetermined control position, the means for electrically operating the normally manually actuated selector units including an elongated pinion common to all of said units, energizable means for driving said pinion, each of said units having an actuating portion with a gear rack thereon, an operating portion, means for slidably supporting said two portions for linear movement toward said control means but permitting pivotal movement of the gear rack on said actuating portion into and out of operative engagement with said pinion, said actuating portion normally being disengaged from said pinion, adjustable means operatively connected with said operating portion and movable thereby into operating position with said rotary control means, electro-magnetic means including a pivoted armature connected with said actuating portion. a circuit for said electro-magnetic and energizable means, said armature on energization of said circuit pivotally moving the gear rack on said actuating portion into engagement with said pinion. which in turn linearly moves said actuating and operating portions toward said control means.

3. Control apparatus including rotary control means, a selector unit for turning said rotary control means to a predetermined control position including an actuating member having a cam portion, an operating member engageable with said actuating member and movable thereby, frame means slidably supporting said two members for linear movement toward said rotary control means, an adjustable element mounted on said operating member and engageable with said rotary control means, electro-magnetic means including a pivoted armature for moving said operating member, clutch means movably connected to said armature, said clutch means being in engagement with said actuating member, and an energizing circuit for said electro-magnetic means including a normally open controlv switch mounted in said'frame means and engageable with said cam portion, with initial linear movement of said actuating member toward said rotary control means closing said switch to energize said electro-magnetic means and moving said clutch means to engage said operating member, to provide for the linear moving of said operating member toward said rotary control means by the combined action of said electro-magnetic means and the continued movement of said actuating member.

4. In electrical control apparatus having frame means and control means rotatably supported in said frame means, a plurality of selector units for rotating said control means to predetermined control positions, each of said units including an actuating member, a carriage member movable by said actuating member, said two members being slidably supported in said frame means for linear movement toward said rotary control means, an adjustable element on said carriage member engageable with said rotary control means, a gate member common to all of said units, axis means pivotatlly supporting said gate member in said frame means, electro-magnetic means operatively associated with said gate member to pivotally move the same, means operatively connecting said actuating and operating members including a spring-pressed lever pivotally supported on said gate member and in en- 4 gagement with said actuating member, and an energizing circuit for said elctro-magnetic means including normally open switch means mounted in said frame means in the path of movement of said actuating member, with initial movement of said actuating member pivotally moving said lever to operatively connect said.

5. In electrical control apparatus having a rotary control shaft and an adjustable control member and toothed means thereon with the latter means operatively connected with the former member in shaft operating position, the combination of an operating member in continuous meshing engagement with said toothed means, means slidably supporting said operating member for linear movement but permitting pivotal movement thereof about said toothed means, electrically driven driving means, said operating member having a clutch portion movable into and out of engagement with said driving means on pivotal'movement of said operating member, said clutch portion when in an engaged position connecting said operating member for linear movement by said driving means, means for normally holding said clutch portion out of engagement with said driving gear, and selectively actuated means for pivotally moving said clutch portion.

6. In electrical control apparatus embodying rotary control means and a plurality of actuating units for rotating said control means to predetermined control positions, with each of said units including a linearly movable operating portion and adjustable means movable by said operating portion into a position to rotate said rotary control means,'the combination of electrical driving means common to all of said units, clutch means for each of said units including'an actuating portion for linearly moving said operating portion, means slidably supporting said actuating portion for linear movement by said driving means but permitting pivotal movement thereof into and out of engagement with said driving means, means for normally retaining said actuating portion out of engagement with said driving means, and selectively actuated means for operating said clutch means.

'7. In electrical control apparatus having a ro tary control shaft and a plurality of selector units for rotating said control means to predetermined control positions, with each of said selector units including a linearly movable operating member and an adjustable element supported on said operating member and movable thereby into a shaft operating position, a manually operated actuating member for movingsaid operating member, means slidably supporting said actuating member for linear movement, a clutch member in engagement with said actuating member and movable thereby into engagement with said operating member, electro-magnetic means including an attractable element, means pivotally connecting said clutch member and attractable element, anda circuit for said electro-magnetic means includ-,

ing normally open switch means arranged in the path of movement of said actuating member, said actuating member being adapted on initial manual moving thereof to move said clutch member to operatively connect said attractable element with said operating member. and to close said switch means to energize said electro-magnetic means to'move said operating member concurrently with the continued manual movement of said actuating member.

8. In electrical control apparatus havinga rotary control shaft and a selector unit for rotating said shaft to a predetermined control position, said selector unit including an operating member and an actuating member for manually moving said operating member, means slidably supporting said two members for linear movement toward said shaft. an adjustable element supported on said operating member and movable thereby to a shaft operating position, a pivoted member for electrically moving said operating member, a clutch member operatively connected with said pivoted member. and en aged at one end with said actuating member, with the opposite end thereof being enga geable with said operating member. energizabie means for driving said pivoted member. and a circuit fo said en-' ergizable means includin a normally opened switch arranged in the path of movement of said actuating member, said actuatin member on initial movement thereof pivot-ally moving the opposite end of said clutch member into engagement with said operating member and closing said switch so that said operating member is moved toward said control means by the combined action of said actuating member and energizable means. v

9. In a radio tuning system including frequency changing means and a control shaft adapted to move said frequency changing means to predetermined tun ng positions, a plurality of control units including a linearly movable operating member having an adjustable element thereon engageable with said shaft. a manually op erated actuating member. a pivoted trio lever for operatively connecting said two members, said lever being in engagement with said actuating member, electro-magnetic means including an armature for driving said trip lever to move said I operating member. means pivotally supporting said'lever on said armature. and a circuit for said energizing means including a normally open control switch arranged in the path of movement of said actuating member, said actua ing member being adapted to be manual y pushed to pivot said trip lever into engagement with said operating member and to close said switch means to energize said electro-magnetic means so that' said operating member is moved by the coop and said actuator member.

10. In a radio tuning system having frequency changing means and a control shaft adapted to move said frequency changing means to prede termined tuning positions, a plurality of selector units, witheach of said units including' a carriage and means -slidably supporting said two members said carriage member for linear movement but permitting pivotal movement thereof about said for linear movement toward said control shaft,

electro-magnetic means common to all of said units including a pivoted armature, a clutch member for operatively connecting said armature and carriage member, pivotally supported on said armature and movable thereby to move said carriage member, means for normally retaining said clutch member in a neutral position in engagement with said actuating member and out of engagement with said carriage member, and a cir-' cuit for said energizable means including a normally open switch adapted to be operated by said actuating member, with initial movementof said actuating member pivotally moving said clutch member into engagement with said carriage member and closing said switch to provide for a combined manual and electrical moving of said carriage member to its shaft operating position.

11. In a tuning device for radio receiving anparatus having a rotary control shaft. a plurality of control units mounted on said shaft, with each of said units including a pair-of freely rotatable members and an adjustable member arranged therebetween. with said latter member and rotatable members being operatively connected in a shaft operating position. a carriage member in continuous engagement with each of said rotary members, a rotary driving member common to all of said units, energizable means for operating said driving member, means supporting shaft, said carriage member having a clutch portion thereon movable into and out of engagement with said driving means on pivotal movement thereof, means for normally retaining said clutch portion out of engagement with said driving means. second energizable means connected with said actuating member for moving said clutch portion into engagement with said driving memher, and a circuit common to said two energizable. means arranged to provide for their concurrent energization.

12. In electrical tuning apparatus for a radio receiver having rotatable tuning means, means for rotating said tuning means to predetermined tuning positions and including a rotary control unit having a pair of freely rotatable gears and an adiustable member thereon. with said gears operatively connected with said latter member in shaft operating position, an operating'member in continuous engagement with each of said gears and arranged to rotate sa d gears in opposi e directions, means for slidably supporting said operating member for linear movement but permitting pivotal movement thereof, electricali driving'means for operating said control units.

. erating action of said electro-magnetic means said operating member having a rack portion movable into and out of engagement with said driving means on pivotal movement of said operating member, means norma ly re aining said rack portion out of engagement w th said driving means, and electrical means including a spring-pressed pivoted armatu e connected with said operating member for moving said rack portion into engagement with said driving means, said two electrical means being connected in series for concurrent energization. -13."In electrical control apparatus having rotary control means and a plurality of selector units, with each unitincluding a linearly movmovable thereby into able carriage member, adjustable means operatively connected with said carriage portion and an operating position with said rotary control means,- an actuating portion for moving said carriage member, means slidably supporting said actuating portion for linear movement but permitting pivotal movement thereof, a rotary driving pinion common to all of said units, said actuating portion having a gear rack thereon pivotally movable into and out of engagement with said pinion, means normally retaining said actuating portion out of engagement with said driving pinion, and selectively actuated means for moving said gear rack into engagement with said driving pinion to provide for the moving of said carriage portion by said actuating portion.

v 14. In electrical control apparatushaving a rotary control shaft and a plurality of selector units for rotating said shaft to predetermined control positions, m'th each unit including a linearly movable operating member having an adjustable elementthereon engageable in an operating position with said shaft, the combination of a rotary member common to all of said units, electrical means for driving said rotary member, a member for actuating said operating member having a rack portion thereon engageabie with said rotary member, means slidably supporting said actuating member for linear movement but permitting pivotal movement thereof to move said rack portion into and out of engagement with said driving member, means for normally retaining said actuating member outof engagement with said operating and rotary members, and electrical means including a spring-pressed pivoted armature connected with said actuating member, said armature on movement to a closed position pivotally moving said rack portion into engagement with said rotary member, with said two electrical means being connected in series for concurrent energization.

15. I control apparatus having rotary control mechanism movable to a control position, the means for moving said rotary control mechanism to a predetermined position including in combination actuating mechanism, with one of said two mechanisms having a part therewith adjustable to a position corresponding to a predetermined control position and being movable to move said part into operating connection with the other mechanism, magnet means with a pole face energized substantially upon initiation of a moving operation, and means connecting said magnet means with said actuating mechanism including a spring-tensioned multi-portion means having a first portion normally out of an operating position relative to said actuating mechanism but being pivotally movable into an operating position relative thereto substantially upon initiation of said moving operation for said rotary control mechanism, and having another portion pivotal relative to the first portion, connected therewith, and acting to maintain the first portion in the operating position during the rotarycontrol mechanism-moving operation, with said second portion having an armature part in substantially fiush engagement with the pole face during at least the last part of the moving operation.

16. In controlapparatus having rotary control mechanism movable to a control position, the means for moving said rotary control mechanism to a predeterminedposition including in combination actuating mechanism, with one of said two mechanisms having a part therewith adjustable to a position corresponding to a predetermined control position and being movable to move said part into operating connection with the other mechanism, electrical means for operating said actuating mechanism, and means for operatively connecting said electrical means with said actuating mechanism including a springtensioned multi-portion means having a first portion normally out of an operating position relative to said actuating mechanism but being pivotally movable into an operating position relative thereto upon initiation of a' moving operation for said rotary control mechanism, and having another portion pivotal relative to the first portion, connected therewith, and acting to maintain the first portion in the operating position during the rotary control mechanism moving operation.

17. In control apparatus having control mech-, anism movable to a control position, the means for moving said control mechanism to a predetermined control position including in combination means initially manually movable, and electrical means energized substantially upon initiation of said manual movement to at least assist in the completion of a movement of said control operation, and means mechanically connecting the manual means and the electrical means including a pivoted member, a second pivoted member mounted on said first pivoted member and engageable by said manual means upon movement thereof to be pivoted by such engagement with said manual means into a driving position, and a switch engageable by said manual means upon initiating movement thereof electrically connected with the electrical means to energize the same for moving said first pivoted member.

'18. In control apparatus having movable control mechanism and a plurality of selector units for selectively'moving said control mechanism to a predetermined position, the means for driving a selector unit including a driven pinion common to all of said units, means for connecting said unit with said pinion including a gearrack member movable into and out of engagement with said pinion and operatively connected with the selector unit, magnet means energizable substantially upon initiation of a control operation, and an armature for said magnet means pivotal relative thereto and relative to said gear rack member having a magnet engaging portion at one end, and a yieldable portion at the other end engageable with the gear rack member and being yieldable to adapt the armature to varying lateral positions of'the gear rack member while permitting a substantially flush engagement between the magnet engaging portion of said armature and the magnet means, with said pinion upon the positioning of said connecting means for operation acting to move the gear rack member and the selectorunit therewith.

19. In control apparatus having control mechanism movable to a predetermined position, the

" the magnet, and a yieldable portion at the other end engaging the rack member and upon energization of the magnet moving said rack member into engagement wtih the rotary gear.

20. In control apparatus having control mechanism including a rotary shaft having driven gear means thereon, the means for driving said gear means and the shaft to a predetermined control position including in combination a driving member having a portion in engagement with said gear means and another portion toothed for driving engagement with a driver, a driver,

with said driving member normally being out of engagement with said driver, and means for pivoting said driving member into engagement with said driver, including a magnet, and a pivoted armature attracted at one end to the magnet, and having a portion engaging said driving member to pivot the same.

HAROLD F. ELLIOTT.