US2496424A - Radio tuning device - Google Patents

Description

Feb. 7, i950 L. M. TEMPLE 2,496,424

RADIO TUNING DEVICE Filed July l0, 1946 2 Sheets-Sheet 1 www FIG. 2

7 4 1/4 52 59 333 33C /oo /1/ 35 412 543443/3 53 5458 s# 75 SE'; 'ell-UA1 nxt- PE- j L. M. TEMPLE RADIO TUNING' DEVICE Feb. 7, 1950 2 Sheets-Sheet 2 Filed July 10, 194e Patented Feb. 7, 1950 RAMO TUNINQDEWCE -Lemue1 M.:Temple,-ScarsdalefNs' assigner to :Raytheon Manufacturing Company, xNewton, ali/lass.,-v a Ycorpo ragtion of Delaware `Appiitatim Ju1yg 1o, 1945sena1 10,652,505

This invention relates to radio receivers ofthe subfminiature type, and more particularly tothe construction of -suchdevices It is a main object of the present-invention to provide a device of the typedescribed having such e dimensions that same can-be convenientlyW carried on theperson rof Vtheruser thereof.

Another objectof the present invention is 4to provide a device of the `type described which shall be encompassed-within a framework -ofwsubstantially shallow proportions suitable forinsertionfin the vest-pocket of a user thereof.

For amore complete comprehesion-ofthe above and other objects of Ithe present'invention,.refer ence is hadveto 'the f' following description andA attached drawings, in which:

Fig. 1. -is aplanview ofthe deviceof'the present invention;

Fig. 2 represents a View ofv one edge oivthefdevice of the y present invention ..to=i11ustrate,-. substantially, the shallowconstructionl thereof;

Fig. 3 depictsA a-plan view of `the.opposite2side of Fig. 1; y

Fig. 4 presents an end View of the device-illustrating the controls and frequency indicating` means;

Fig. 5 is a cross-sectional viewof' the,Y tuning drive; and

VVFig. 6 presents `anexploded-viewlpffthe'device.

-fReferring toFigs: 1,:2; and 3, thefidevice-ofethe -present invention comprises a plurality-offshallow compartments, 13,. Il, l2,4 |3.and 14. mWhen speaking of compartmentsin connection with the description of the device of this inventiom'the term encompasses metal framemernbersll,` 3|,

32, 33, 34, 35, 36, 31 and cover 49 (.cover shown in partial-cross-section). A11 lois-,said compartments are combinedfinto alshallow substantially rectangular assembly.

Compartment encompasses a-.p1urality'of capacitors l5, 16, 11,118, and apair-of resistors I9, three of said .capacitors beingfastenedv to frame member130, for example; by riveting -the supporting bands -I 5A, .1| Afand'lflA thereto. vExtending into compartment i0 are a `plurality ofv Y ;.;2 placed, within compartment jl3,V together -f with shieldedpermeabilityhtuned stages 38:39, and-40, saidjlast-named [stagesn being ilrmly affixedIl to fr ame vmemberjby `fastening extended portions Y4 i j 42, andi 43 ofsaidshieldedstages to said frame member-35 with screws; 44; 45, andhy as -shownin Figs-2 and. Also'plac'ed within said compartment I3 are shielded intermediate-frequency stages-41 andwl,l said stages being-fastened to frame member 3l by screws 50-and 5! Capacitors-'52,153,- andfll are soldered toterminal points 55,f56, vlandel,` as -indicated-more f-clearly in Fig: 2, resistor-58 being vsolderedto Ater- -minal pointy 155. IThe aforegoing terminal4 points are*` carriedbyeoinsulatingmemben.33 which itself isflfastenedl-to irame-emembere.

Within compartmentd Zand heldenk good electrical contactbyspring' members S3 t l ,-.and 32, aref dryvcellsi 63, 64,y andl vE55. eCell" 334s -thefhigh potential source whilecells Vtiliand.Y 65 efurnish Lthe necessary current for:thefilaments` of electron- :discharge*tubes-125,@25,221# 28, and-.129. .,Spring members-30; 6I,- and 63 are heldvinrpositiorrby supporting-members:610A, 61A, and 32A-said lastnamed supportingmiembers being-rigidly a-lixed to-frame member .-32.

A novel switchingi arrangement. vfor said `dry cells is providedby-i-rame..member; 32. .Said memben32 isattaehedto a second metalemember -65. `by. screws 'l l), `said .member 6 hav-ing. a slightly larger areafthan saidmemberfSZ. Aknurled` and threaded memberv'tfis zthreadedly..engagedfwith aninsulating, member Q68 `througlri aperture 63 in membery 34` and through. apertures .(notshown) .in membersi 32 and. .66. Rotating 1 member.; El .in v4the proper: direction.causes.memben-32v to. separatel :from Jframe, member. ..34 .at pointr .713-, and .by this means tobpenrthe circuit.,which.conductsrythe VIV,potentials suppliedby-drycells 64, and, said t.frame/r members.. being: ithe, :ground .point jfor .the nradio. components of lthe presentdevice. fFig; 3 f shows .the..position ,ot frame.,.memberl 34 ,in intimate..contact:withmerriberglt2v and inthis position thepotentialecarryina:circuit -is closed oncom- Apleted andv current .supplied l:to `the components lof the device.

. Attention. is..cal1ed, to uframe. member..V 33..which .is-.madez.up offitthreegfparts, .33,133A,v and 353B. .Members 33....and 33A-are.made-.-of.meta1, spaced apart. land riveted l.to insulating,-memberw33B- The purpose of E this..par.ticular .construction .is 4to avoidy conductingcurrent .rfrom.-.dry. cella. .63,y 54 yandfthrough `this part .of sthezstructure as',y its function is4 to .support said: drycells within. compartment l-l 2I andmmemberf 33A..particu1arly.frunc tions to maintain members 32 and 86 in position at point 15. The bent portion 33C of member 33A laps over member 62A and acts as a fulcrum at point 15 for members 32 and 66.

Metal contacts 1| and 12 are attached, by riveting, for example, to insulation member 14. and current from the plus side of the aforementioned dry cells is conveyed via conductors 16 and 11 to the various components requiring said current.

Member 66 is made slightly larger, in this particular embodiment, than member 32, said members being held together by screws 10. This particular arrangement maintains cover 49 in position when it is slipped over the entire assembly as the combination of 32 and 66 form a. shoulder 66A against which the cover 49 abuts. If it is necessary to remove said cover to repair or replace any of the components, member 61 is unscrewed from its position entirely and combined members 32 and 66 lifted from the assembly.

Fig. 2 illustrates an edgewise view or" the structure and shows in plan view frame members 33, 33A, 33B, and 35 and end views of frame members 32, 66, 34, and 36. It also shows inductors 38A, 39A, and 40A, said inductors being iitted into apertures in said frame 35. These lastnamed inductors are enclosed in shielded stages 3s, 39, and 40.

Volume control knob is a combination of a hollow knob with a variable resistance (not shown) therein and is attached to member 36.

Placed between frame members 36 and 18 is a tuning drive which comprises, as illustrated in Figs. l, 2, and 3, rack 19, and rack support 80.

Said rack support is fastened to member 36, for

example, .by screws 8|, 82, and 83; screw 83 also holds in place, on member 18, a transparent dial 84. Fastened to rack 19, for example by screws 85, is a fiat L-shaped member 86, said L-shaped member having fastened to the longer arm thereof a plurality of permeability tuning cores 81, 88, and 89. Attached to said L-shaped member at the junction of the arms of same is a dial pointer 90, said pointer being fastened to said L-shaped member, for example, by screw 9|.

Fig. 4 is an open view of the tuning drive and illustrates in greater detail the arrangement of rack 19 and the driving pinion gear 94 which imparts to said rack a linear motion. Said linear motion is also imparted to member 86 which supports the powdered iron tuning cores 81, 88 and 89 as described above in connection with Figs. 1, 2, and 3. Pinion gear 94 is tightly fitted to shaft member 93 as by sweating same onto said shaft or by other suitable means. A dial 84, having inscribed thereon designations for locating desired broadcast programs, is fastened over an opening in member 18 by screw 83.

Fig. illustrates in cross-section the manner in which rack 19 is held in position between members 36 and 18. Member 36 has along its entire length a slot 95 into which is tted a raised ridge 96, said ridge being integral with rack 19 and continuous along the entire length thereof. The opposite side 91 of said rack is in slidable contact with member 80, said member 80 being held in this position by screws 8| and 82 as illustrated in Fig. 3. Adjacent driving pinion gear 94 is a spring-loaded pinion gear 98 having the same number of teeth and pitch, but not as thick as gear 94, said gear 98 being loosely fitted to shaft 93. Disposed between said gears is helical spring member 99, said spring being fastened at one end to gear 94 in a recess therein, the other end being bent perpendicular to its length and placed man 4 aperture in gear 98. Gear 98 is rotated so that spring 99 becomes tightly wound and the teeth of rack 'i9 are meshed with the teeth of both gears 94 and 98. This causes the teeth of gears 94 and 98 to exert pressure in opposite directions within the working depth of the teeth of rack 19 and thus eliminates play or backlash between said rack and pinion. Tuning knob 92 is attached to shaft 93 vby suitable means such as a set screw or the like.

' Despite the diminutive size of the device of the present invention, the novel construction of the frame members and the means for combining them provide a structure which can be readily and rapidly assembled. It would appear at first glance that a radio receiver constructed along linesdescribed and illustrated would present a most difficult wiring problem. Such is not the case. Every frame member serves to support some of the various components that go into the construction of the present device and it will be shown by Fig. 6, an exploded view of the device, that the novel arrangement and configuration provide means for rapid wiring and assembling of said device.

Referring now to Fig. 6, frame member 35 has affixed to it permeability tuned stages 38, 39, and 48, said stages being fastened to said frame member 35 in the manner hereinbefore described. Also supported by said member are a plurality of capacitors 52, 53, and 54 and resistors 58 on either side together with a terminal strip 59 to which said capacitors and resistors are fastened. The wiring of components for this particular frame member is completed and suilicient lengths o! wire are provided to connect these last-named stages to other components. Both ends |02 and |03 are turned up perpendicular to the main part of member 35, said ends having apertures |04 and |05 provided therein for the passage of fastening means therethrough. Also attached to said member 35 is earphone |30, the leads 3| from said earphone serving as an antenna and conductor for the audio frequency output of the device.

Now frame member 31 is prepared and it carries sockets 20, 2|, 22, and intermediate stages 41 and 48. All the Wiring that can be completed for this structure is done and as before suiiicient lengths of wire |06 are left unterminated for connection to other stages or components. The ends |01 and |08 of member 31 are slightly narrower in width than the main body of said member to form tongues which t into apertures |09 and ||0 provided for them in members 34 and 36, respectively.

Frame member 30 supports a plurality of capacitors and resistors, a portion of the capacitors l5. |6, and |1 being supported by metal bands !5A, |6A, and |1A surrounding same, said bands being riveted, for example, to frame member 30. All the aforesaid components are Wired as ex plained hereinbefore and enough extra wire left for connections to other parts of the device. Ends ||2 and ||3 are bent perpendicular to the main member 30 and have apertures I4 and I5 provided therein for fastening to frame members 34 and 36. Notches ||8 and ||1 are provided to hold in position frame member 3|.

Frame member 3| supports two sub-miniature tube sockets 23 and 24, which in turn support two sub-miniature radio tubes 28 and 29. The sockets have wires ||8 connected thereto and as in the other frame members sufficient wire is left to-,providefor other connections. Framel memarcane:

ber 3| is formed with twoextended portions ns and to t two notches' 2| and |22 in frame member 34.` The edge opposite4 the extended portions ||9 and |20 has a notch |23, which fits across the material in the space between notches H8 and ll'i'with a snug fit. When ally the frame members are fastened together, frame member 3| will be held firmly between frame" members and 34.

Frame member 34 is a substantially L.Shaped member, the base thereof having a portion I 24 bent perpendicular thereto and. in a direction away from the leg of said frame member 34, said last-named leg having fastened thereto an. insulating member |25 for supporting thereon contact plates 1| and 12 (not shown in Fig. 6 but illustrated in Fig. l). Lead wires |26 and |21 are fastened to said contact plates and provide the means for conducting current to the radio tubes. Attached to inside of the junction at bent portion |24 is an insulating member 6B having affixed therein a tapped metal member for receivingl threaded member 61, the insulating member 68 serving to electrically insulate member 61 from frame member 34 when said members are separated as explained hereinbefore.

Members 33, 33A, and 33B form an integral member, 33 and 33A being formed of metal and 33B of an electrically insulating material such as Bakelite or the like. Both members 33 and 33A have one end bent perpendicular to the main portion thereof. End |28 has apertures |29 provided therein for fastening said member 33 to member |25. End 33C serves as a fulcrum, when placed in space 15 between members 62A and 36, for members 32 and 66 when same are caused to move out of contact with member 34 by manipulation of threaded member 61 (as illustrated in Fig. 1). Spring members G, 6|, and 62 provide the urge necessary to separate members 32 and 66 from frame member 34. Said springs are held in position on member 32 by innerly grooved, partially circular members 60A, 6|A and 62A, said springs providing a strong point of contact with the negative side, for example, of dry cells 63, 64 and 65 (not shown in Fig. 6 but illustrated in Figs. l, 2, and 3).

The combination of members 34, combined members 33, 33A and 33B, and combined members 32 and t6, form a compartment for the aforementioned dry cells.

Frame member 36 serves to support the tuning drive mechanism which includes rack 19, rack-supporting member 3U, driving pinion shaft 93 and other portions of said drive (not shown in Fig. 6) .l Member 8|! is fastened to member 36 as hereinbefore described and thus holds in place the various components making up the tuning drive.

Member 18 supports the combined volume control and knob |03 and transparent dial 84. It is provided with an aperture 18A which ts over boss 83A, and shaft member Q3 extends through said aperture 18A when member 18 is fastened to member 36 through apertures 36A and |05. After member 18 is fastened in place to member 36, tuning knob 92 (see Figs. l, 2 and 3) is fastened to shaft 93.

After all the preliminary wiring of the various components, as hereinbefore described, has been done, member 31 is fitted to member 36 by insertion of tongue |61 into aperture |(l. Then member 34 is placed in position so that tongue |68 ts within aperture |29, member 34 being fastened to member 35 by means of screws, or the like, inserted through apertures |04 and 34A. Member 6g 3i is now wired in position by' connecting wires H18. After all the necessary wiring connections' are' made, end |3 of frame member 30 is fittedto member 36 and fastened thereto by means' of screw 83 inserted through aperture 36A and threaded aperture H5. Member 3| is'now placed in notches ||6 and I1 of member 3|) and the ex.-- tended portions ||9 and |20 placed in notches |2| and |22- of member 34. With these lastnamed components in position, end portion I2A is fastened to portion |24 of member 34 by means of screws (not shown), orV the like, inserted through aperture 34B and-threaded aperture |4. Member 33 is fastened by screws (not` shown) to member These aforementioned oper-ations point out the ease with which the device may be assembled; although the steps indicated are the preferredy ones, the assembly may' bel carried out in any*v manner` desired. All fastening is accomplished by the use of Screwsv or bolts which are preferred,

although it is also possible to useother means for holding the various' compartments together and still retain the feature of ease in assembling and dismantling the device of the present invention as by means of interlocking or the like.

Members 32 and 66 are fastened together by screws 19 and are the only members not semipermanently fastened. This arrangement permits the user of the device to replace the dry cells when necessary and requires only that member 61 be completely unscrewed from threaded member I 24A.

The device as described provides a novel construction, the overall depth of said structure being governed by the thickest component therein. Although this particular embodiment describes the use of the device in connection with a miniature radio receiver, it is also adaptable to hearing aids, electronic stethescope amplifiers, and other devices requiring a thin flat structure according to the device of this invention.

Having described the device of the present invention, it should be understood that many modiiications Will occur to those skilled in the art but such modifications do not represent a departure from the true spirit and scope of the present invention.

What is claimed is:

l. In combination, a radio receiver having a substantially rectangular metal supporting frame therefor, said frame being divided into contiguous compartments for supporting therein the components of said receiver, and all of said components lying in a single common plane transverse to the thinnest dimension of said frame to form a shallow assembly, the depth of said assembly being substantially equal to the thickness of the thickest one of said components.

2. In combination, a radio receiver having a substantially rectangular metal supporting frame therefor, major components of said receiver being supported between the longer parallel members of said frame, tuning means for said receiver, said means being supported by one of the shorter members of said frame, and all of said components lying in a single common plane transverse to the thinnest dimension of said frame to form a shallow assembly, the thickness of said assembly being substantially equal to the thickness of the thickest one of said components.

3. In combination, a radio receiver having a substantially rectangular metal supporting frame therefor, major components of said receiver being supported between the longer parallel members' of said traine, all of 'said components lying in a single common plane transverse t0 the depth dimension 'of said frame to form a shallow assembly, the thickness of said assembly being substantially equal to the thickness of the thickest one of said components, and a dust-proof cover completely enclosing said frame and said components.

4. In combination, a radio receiver having a permeability tuning device comprising at least one inductance and a movable iron core sldably mounted within said inductance, a rack attached to said core and extending parallel thereto, rotatable means threadedly engaged with said rack for imparting linear motion to said rack and core, a rectangular metal frame for supporting said tuning device, rack and rotatable means within the con'nes thereof, a dust-proof cover completely enclosing said frame and the tuning device components therein, and means located exteriorly of said cover for manually actuating said rotatable means.

LEMUEL M. TEMPLE.

il REFERENCES CITED The following references are of record in the file of this patent:

Candid Radio Receiver of the Sonora R. and T. Corp.

Images