US1890721A - Tuning apparatus - Google Patents

Tuning apparatus Download PDF

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US1890721A
US1890721A US37634A US3763425A US1890721A US 1890721 A US1890721 A US 1890721A US 37634 A US37634 A US 37634A US 3763425 A US3763425 A US 3763425A US 1890721 A US1890721 A US 1890721A
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wiper
contacts
arm
contact
shaft
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US37634A
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Hiram D Currier
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Kellogg Switchboard and Supply Co
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Kellogg Switchboard and Supply Co
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    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03JTUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J3/00Continuous tuning
    • H03J3/24Continuous tuning of more than one resonant circuit simultaneously, the circuits being tuned to substantially the same frequency, e.g. for single-knob tuning

Definitions

  • My invention relates to the tuning of coulplersor transformers as are used in wireless the manner in which t e coils are mounted and associated with one another to obtain the desired and most etlicient resultswhen used in a radio receiving system.
  • a still further featurev is the construction, arrangement and control of the apparatus by which the inductan'ce ⁇ of the secondaries of the transformers or couplers is varied in steps by means of a single ⁇ multiple control arrangement and .the inductance within the steps isV varied by means of a separate single multiple control arrangement, thus making it possible to control a plurality of devices il the manner in which the contactk arms with a single control knob.
  • Another feature of my invention residesfin or varying the inductance of the transformers by steps are associated with the multiple control arrangement.
  • VAnother ⁇ feature of my invention resides in theprovision of means for maintaining the exact coordination of the shafts used for varying the inductances of the transformers or couplers within the steps of variation of the secondaries of the'said coils.
  • Fig. 1 is a top view of the apparatus com-v prising my invention mounted in position;
  • Fig. 2 is a front view of one of the panels upon which a Wiper arin and its associated contact points are mounted;
  • Fig. 3 is a sectionalview drawn along the line 3 3 in Fig. 2;
  • Fig. 4 is a rear view of Fig. 2 ⁇
  • the devices T, T and T2 are each provided with ⁇ a stator tube or supporting devlce S, S and S2 respectively.
  • the stator coil supporting devices S, Syand S2 are mounted upon a baseboard' by any suitable means and are also provided with brackets 6 in which rods 7 are rotatably mounted
  • the rods 7 are composed of any suitable insulating material and aresecured ⁇ together byfmeans ofl collars 8, also composed ofv insulating material and provided lwith a central oriice into which the ends of the rods 7 are inserted.
  • the collars 8 ⁇ are secured to the rods 7 by means of set screws 9 to assure the rotation of all the rods 7 in synchronism. lt will be seen from this that any number of devices T, T and T2 may be added vWithoutaffecting the mounting or arrangement of those already present.
  • the rotor coils R, R and R2 are provided with brackets 10 to which are securedcollars 11 adapted to be fastened to the rods 7 by means 12 to cause the rotor elements to rotate, when the rods 7 are rotated.
  • These devices are of the 180 degree coupler type, so that the rotor elements may be rotated 180 degrees or until they are at right angles to the plane of the stators.
  • One end of the shaft 7 which supports the rotor of the device T extends through a supporting device 13 and is provided with a bevel gear 14 secured to the rod 7 by any suitable means.
  • a second shaft 15 is supported by the device 13 and has a bevel gear 16 in mesh with the'bevel gear 14 to ⁇ cause the simultaneous rotation of the shafts l5 and 7.
  • Y shaft 1.5 passes through an orifice provided in the panel 17 and has secured to its protruding end a knob lK adaptedto be rotated to cause the shafts 15 and 7 and the rotor elements R, R and R2 to revolve.
  • the knob K" is providediwith a pointer'P and suitable graduations may be placed upon the front of the panel 17 to in-A dicatethe degree of rotation ofthe rotor elef ments.
  • a stop 18 secured tothe panell'? is provided withr'earwardly extending arms Vcollar 20 adapted to'fbe rigidly secured tothe shaft l5 by means of a Vset ⁇ screw 21.”
  • the ⁇ collar'20 maybe slid longitudinally valong gthe Vshaft 15.
  • ⁇ set screw 2l is of a. length 'suiiici'ent to engage the protruding ⁇ endsfof the stop 18 to effectus'haft 15.
  • VThe stator coils are tapped andthese taps are led to contact pointsv 22 mounted on panels MP, MPV and MP2. Allthe panels being'otl similar'construction and arrangement the description of one. -willv suice fora clear explanation ofall.
  • the mounting ⁇ ⁇ panel 1s composed of any suitable insulating'materi'al. ⁇
  • the contact points 22 are inserted insuitable orifices provided in the panel MP l and are provided with heads 23 largerftha'n the orifices through which they are inserted;
  • the other end of the contact is thenjstaked over orminga shoulder 24 lwhich'. prevents the longitudinal movement ofthe contact and holds it sec'urelyin place.
  • the taps or leads 2 5 are fastened to the contacts 2.2 by any suitable means such as solder.
  • Thecontactsare placed in an, are ofia circle andthe wiper arm 26 is adapted to'pass over and contact with the Contact points 22.
  • J y y The wiperj26 is provided with a raisedportion 27, which is adapted tovcontact with the V'est contacts 22 when the wiper 26 is rotatedV as will be described hereinafter.
  • the orifices 29 are equal rin numberV to the contacts 22 and are so placed that when theraisedportion 27 of the Wiper 2,6 is squarely over: afcontact 22.1 thestud 28 is vresting in the corresponding.
  • the wiper arms 26. 26 and 262 are, multiply controlled or adapted to v be moved ycorresponding distances simultaneously, ⁇ so thatthe inductances of thetransformers T, T', and T2 may be varied by placscrew threaded engagement with the screws 30, ⁇ also washers 33 are provided and inserted between the nil-1:8131 and 32.
  • the bracket B is secured to thel baseboard 5 by means of screws'34.
  • -" ⁇ Y "I" metal bushing 35 has itsr'reduced end portioni ⁇ 35 insertedintoa suitable orifice provided inthe mounting panel MPland is Aheld in placeby means of anut v37-Which ⁇ has screw threaded lengagement with the reduced portion"35.
  • Thebushing35 isprovided withla central orifice through which is inserteda shaft V38 which has a reduced end portion' 38".
  • a nut 39 is adapted to enter into screw' threaded Vengagement.
  • the arm 41 has riveted thereto a stud-42adapted toengage-an opening' in the .wiper arm 26 to guide and move the same in theirsame ldirection andthe samev distance as the arm 41 ismoved.
  • a bar 44' Fastened to the arms 41, 41l and'412f by meansiof-rivets 43 is a bar 44'provided to simultaneously move thearms 41,. 41"and 412.
  • i-Extendingthru 'an orifice in the panel 17 isa sleeve having an enlarged portion 45; yand a screw threaded portion to Areceive a nut 46 to hold the same in position.
  • the said vsleeve is provided with an orifice thru which-the shaft 45' ext ⁇ ends.
  • Attached to a collar 99 is an arm 47.
  • The' collar 99 is yheld 'in position on the shaft 45 by means of switches..
  • Riveted tothe bar 44 is a stud 48 whichis adaptedfto fit into an'oblong slot in the arm 47.
  • ⁇ YVh'en the knobK is rotated in a clockwise direction
  • Vthe arm 47 causes the 28 drops linto the correspondingoriiices 29 l .which will'happenwhen the"por"tion ⁇ 2",7 isY directly over the contact 22 to which it .has Nbeenrotated..
  • the bottom edgev of the stud 28 is rounded so as to permit itto ⁇ risejout of one orifice .29 ⁇ and ride over the v portion 49 between the orifices 29 before dropping intothe next orifice.
  • the ywipers 26,26 and 26.2 havea certainamount of ⁇ give f ⁇ and the rising ofthestud 28 ⁇ causesftheporf y 'amie-z to be, naeaout of engagement with the contact 22 when the arm 26y is .caused torotate.”
  • Thefportion'27 will not make contact with the next contactj22 until the stud grooving andthe subsequent inefficient operation of ⁇ wl'perarms and contacts as is ⁇ usually y present in vsuch'operations after they have beeninuse for some time.
  • the ⁇ stud 28 is Slightly ⁇ Smaller than the .orifices 29 sofas to f 25 allow a slight amount of playV to allow the portion-.27tobe ⁇ slid on the contacts 22to causeia' goodfcontact to be made. v
  • Ate'rminal, 50 to which an "external conductorV may Vbe attached is provided, and is held inposition ⁇ by the nut 37, to complete an electricalcircuit as is wellunderstood by vone skilled vinthe art. Studs 51 and ⁇ 52 are provided on the panels MP, MP"and ⁇ MP2 to Prevent. excessive @movement of ⁇ the wiper ⁇ arms 26,26and1262. v f
  • a device ofthe character described including a wiper having a raisedportion intermediate itsends adapted to engage a plurality of contacts, a mounting member for ysaid contacts, a rigid arm having a stud engaging said wiper formoving said wiper, and
  • a device of the character described including a rotatable shaft, a wiper and an arm supported by said shaft, said arm ⁇ adapted to cause movement of said wiper from one contact to another of a plurality ofcontacts, and spring means coacting with said shaft and supported thereon, for vary- ⁇ ing the amount of friction betweenthe wiper orifices, associated with said contacts, a wiper having a raised portion intermediate its ends adapted 'to engage said contacts, and a stud secured to the outermost end of said wiper adapted to simultaneously enter said orifices to prevent accidental movement of said wiper and permit the said wiper to engage the said i contacts.
  • a device of the character described including a plurality of stationary contacts, a movable contact for engagement therewith, a mounting panel for supporting said stationary contacts and said movable contact, means for operating said movable contact to cause it to engage'said stationary contacts, and means comprising a studsecured to the outermost end of said movable contact and a plurality of orifices in said mounting panel, said stud co-operating with the portions between said orifices for disengaging said movable contact from one of said stationary contacts when it is being moved therefrom to an adjacent stationary contact.

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  • Transmission Devices (AREA)

Description

Dec. 13, 1932. H. D. cuRRlER TUNING APPARATUS Filed June 17, 1925 Patented Dele. 13, 1932 UNITED STATES PATENT OFFICE Hmm nCUImIEn, or CnICAedILLINoIs AssIGNon rro IIELLCGG sWITCHBoAnD AND SUPPLY COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS TUNING APPARATUS kApplication led June 17, 1925. Serial No. 37,634..l
My invention relates to the tuning of coulplersor transformers as are used in wireless the manner in which t e coils are mounted and associated with one another to obtain the desired and most etlicient resultswhen used in a radio receiving system. 'y f A still further featurev is the construction, arrangement and control of the apparatus by which the inductan'ce `of the secondaries of the transformers or couplers is varied in steps by means of a single `multiple control arrangement and .the inductance within the steps isV varied by means of a separate single multiple control arrangement, thus making it possible to control a plurality of devices il the manner in which the contactk arms with a single control knob.
Another feature of my invention residesfin or varying the inductance of the transformers by steps are associated with the multiple control arrangement.
Y A still further sides inthe construction and arrangement of the wiper arm, its associated contacts and the panel upon which said parts are supported to provide a free and easy movement of the wiper arm over its associated contacts at all times `and at the same time preventthe accidental movement of the wiperv arm.
VAnother `feature of my invention resides in theprovision of means for maintaining the exact coordination of the shafts used for varying the inductances of the transformers or couplers within the steps of variation of the secondaries of the'said coils.
A still further feature of my Vinvention re;A
sides in the provision of Contact wipers which are raised fromr engagement with their contact points when moved from one to the other.
The novel features mentioned above and others not hereinbefore mentionedv will be more fully describedand explained in the following specification and inthe appended featureof my invention re-A `of a set screw claims. Reference may be had to the accom;
panylng drawing In which like reference characters in the different views denote like parts and in Which:
Fig. 1 is a top view of the apparatus com-v prising my invention mounted in position;
Fig. 2 is a front view of one of the panels upon which a Wiper arin and its associated contact points are mounted;
Fig. 3 is a sectionalview drawn along the line 3 3 in Fig. 2;
Fig. 4 is a rear view of Fig. 2`
Referring more particularly to Fig. 1 the devices T, T and T2 are each provided with `a stator tube or supporting devlce S, S and S2 respectively. Mounted within the stator devices are rotatable tubes orrotor elements R, R and R2. The stator coil supporting devices S, Syand S2 are mounted upon a baseboard' by any suitable means and are also provided with brackets 6 in which rods 7 are rotatably mounted The rods 7 are composed of any suitable insulating material and aresecured` together byfmeans ofl collars 8, also composed ofv insulating material and provided lwith a central oriice into which the ends of the rods 7 are inserted. The collars 8` are secured to the rods 7 by means of set screws 9 to assure the rotation of all the rods 7 in synchronism. lt will be seen from this that any number of devices T, T and T2 may be added vWithoutaffecting the mounting or arrangement of those already present. The rotor coils R, R and R2 are provided with brackets 10 to which are securedcollars 11 adapted to be fastened to the rods 7 by means 12 to cause the rotor elements to rotate, when the rods 7 are rotated. These devices are of the 180 degree coupler type, so that the rotor elements may be rotated 180 degrees or until they are at right angles to the plane of the stators. One end of the shaft 7 which supports the rotor of the device T extends through a supporting device 13 and is provided with a bevel gear 14 secured to the rod 7 by any suitable means. A second shaft 15 is supported by the device 13 and has a bevel gear 16 in mesh with the'bevel gear 14 to` cause the simultaneous rotation of the shafts l5 and 7.
They other end of the Y shaft 1.5 passes through an orifice provided in the panel 17 and has secured to its protruding end a knob lK adaptedto be rotated to cause the shafts 15 and 7 and the rotor elements R, R and R2 to revolve. The knob K" is providediwith a pointer'P and suitable graduations may be placed upon the front of the panel 17 to in-A dicatethe degree of rotation ofthe rotor elef ments. A stop 18 secured tothe panell'? is provided withr'earwardly extending arms Vcollar 20 adapted to'fbe rigidly secured tothe shaft l5 by means of a Vset `screw 21." The` collar'20 maybe slid longitudinally valong gthe Vshaft 15. This movement chaiigstle'V tension' of the coil spring 19 and lcauses the bevel gear 16 to always be held in mesh with' l the bevel gear l14 to'prevent any` lost motion between 'the lshaft 7 and theshaftl Vand alsoally lprevent any excessive'rotationV of 'the provides frictional means te maintain the rotor elements in any-adJusted position. The
`set screw 2l is of a. length 'suiiici'ent to engage the protruding `endsfof the stop 18 to effectus'haft 15. Y
VThe stator coils are tapped andthese taps are led to contact pointsv 22 mounted on panels MP, MPV and MP2. Allthe panels being'otl similar'construction and arrangement the description of one. -willv suice fora clear explanation ofall. The mounting` `panel 1s composed of any suitable insulating'materi'al.` The contact points 22 are inserted insuitable orifices provided in the panel MP l and are provided with heads 23 largerftha'n the orifices through which they are inserted;
The other end of the contact is thenjstaked over orminga shoulder 24 lwhich'. prevents the longitudinal movement ofthe contact and holds it sec'urelyin place. The taps or leads 2 5 are fastened to the contacts 2.2 by any suitable means such as solder. Thecontactsare placed in an, are ofia circle andthe wiper arm 26 is adapted to'pass over and contact with the Contact points 22. J y y The wiperj26 is provided with a raisedportion 27, which is adapted tovcontact with the V'est contacts 22 when the wiper 26 is rotatedV as will be described hereinafter. A stud 28 placed near the end of the wiper arm 26 1s slightly smaller "than theorifices 29, located in the 'panel MP. The orifices 29 are equal rin numberV to the contacts 22 and are so placed that when theraisedportion 27 of the Wiper 2,6 is squarely over: afcontact 22.1 thestud 28 is vresting in the corresponding.
` orifice 29.V 'The wiper arms 26. 26 and 262 are, multiply controlled or adapted to v be moved ycorresponding distances simultaneously,`so thatthe inductances of thetransformers T, T', and T2 may be varied by placscrew threaded engagement with the screws 30,` also washers 33 are provided and inserted between the nil-1:8131 and 32. The bracket B is secured to thel baseboard 5 by means of screws'34.-"` Y "I" metal bushing 35 has itsr'reduced end portioni`35 insertedintoa suitable orifice provided inthe mounting panel MPland is Aheld in placeby means of anut v37-Which` has screw threaded lengagement with the reduced portion"35.- Thebushing35 isprovided withla central orifice through which is inserteda shaft V38 which has a reduced end portion' 38". A nut 39 is adapted to enter into screw' threaded Vengagement. Withthis portion 38,5 to vary the tension of afcoil spring 40 placed between the bushing 35 and the said nut 39ltom'aintaina a certainamount of friction'between the wiper 26 and the contacts 22 to assure a good electrical connection.` The shaft 38a'lsohas an enlarged por-tion 38' and the wiper1arm-26 is adapted to'fit on a yportion 383 of thesha'ft-3i8 YWhere it is held in place between the metal bushing 35 and the portion 382' An arm 41 is provided with an orifice adapted to fitove'rthe end of the'shaft 38 which is then rivetedto rigidly secure the arm to the shaft-38 to cause thesame to rotate vas a Whole. The arm 41 has riveted thereto a stud-42adapted toengage-an opening' in the .wiper arm 26 to guide and move the same in theirsame ldirection andthe samev distance as the arm 41 ismoved. Fastened to the arms 41, 41l and'412f by meansiof-rivets 43 is a bar 44'provided to simultaneously move thearms 41,. 41"and 412. i-Extendingthru 'an orifice in the panel 17 isa sleeve having an enlarged portion 45; yand a screw threaded portion to Areceive a nut 46 to hold the same in position.
The said vsleeve is provided with an orifice thru which-the shaft 45' ext`ends. Attached to a collar 99 is an arm 47. The' collar 99 is yheld 'in position on the shaft 45 by means of switches.. Riveted tothe bar 44 is a stud 48 whichis adaptedfto fit into an'oblong slot in the arm 47. `YVh'en the knobK is rotated in a clockwise direction Vthe arm 47 causes the 28 drops linto the correspondingoriiices 29 l .which will'happenwhen the"por"tion`2",7 isY directly over the contact 22 to which it .has Nbeenrotated.. .'lhis,V methodpreventsfthe N n i l The knob K is rotated to change the induc-` i i bar to., move from left to" rightand this i causes the same movement of the yarms4l,41
and 412, and the studs42 in the said armscause'th'e wipers 26 to move from one contact 22 to the next contact etc. `Thebottom edgev of the stud 28 is rounded so as to permit itto `risejout of one orifice .29 `and ride over the v portion 49 between the orifices 29 before dropping intothe next orifice. y The ywipers 26,26 and 26.2 havea certainamount of` give f `and the rising ofthestud 28`causesftheporf y 'amie-z to be, naeaout of engagement with the contact 22 when the arm 26y is .caused torotate." Thefportion'27 will not make contact with the next contactj22 until the stud grooving andthe subsequent inefficient operation of `wl'perarms and contacts as is `usually y present in vsuch'operations after they have beeninuse for some time. [The` stud 28 is Slightly `Smaller than the .orifices 29 sofas to f 25 allow a slight amount of playV to allow the portion-.27tobe` slid on the contacts 22to causeia' goodfcontact to be made. v
Ate'rminal, 50 to which an "external conductorV may Vbe attached is provided, and is held inposition `by the nut 37, to complete an electricalcircuit as is wellunderstood by vone skilled vinthe art. Studs 51 and `52 are provided on the panels MP, MP"and`MP2 to Prevent. excessive @movement of `the wiper `arms 26,26and1262. v f
' Atance of the windings in comparatively coarse steps while theknobvK operates to vary the inductance ofthe secondaries within the stepsof inductance betweenthe taps; In the particular embodiment ,thatI have shown the primaries ofthe devices `(101, `102 and v103) are mounted on the stator portionsrof l the couplers or transformers, while fthe i sec- "ondariesare partly mounted on ,the` krotors and partly on the stator-s, tapped Vin the Vman-l ner described. lIt is ofcourse obvious `that other combinations may` be used such as put-l ting the primaries i on the stators and the secondaries on 'the rotors, etc."
`While I have describedapreferred embodiment of my invention I do not wish to kbe 'limited to the same ybut aim to cover all that comes within the spiritand scope of the appendedclaims. f u
- WhatI- claim as `new and desireto `secure United StatesiLetters Patentis:
levice of the 'character described ,A V cluding ra wiper arm, a raisedportion on varm adapted to engage sets of contacts, said said wiper arm intermediate the endsof said wiperarm being rotatablysupported on a shaft, a rigid `second arm securedto saidshaft fand having astud al'lixedthereto adapted to engage'said first armintermediatesaid raised portionland the'shaft to impart movement to thesaid'wiper `arm when the saidfrsecond armlis moved, and means associated with said` shaft Vfor adjusting the contactual engagement between said Wiper arm'and said contacts.
2. A device ofthe character described including a wiper having a raisedportion intermediate itsends adapted to engage a plurality of contacts, a mounting member for ysaid contacts, a rigid arm having a stud engaging said wiper formoving said wiper, and
means secured to said wiper and cooperating d with means onsaid mounting 'member to effect the lifting of the wiper olf one of said contacts preparatory to moving it to the next contact. v
3. A device of the character described including a rotatable shaft, a wiper and an arm supported by said shaft, said arm` adapted to cause movement of said wiper from one contact to another of a plurality ofcontacts, and spring means coacting with said shaft and supported thereon, for vary- `ing the amount of friction betweenthe wiper orifices, associated with said contacts, a wiper having a raised portion intermediate its ends adapted 'to engage said contacts, and a stud secured to the outermost end of said wiper adapted to simultaneously enter said orifices to prevent accidental movement of said wiper and permit the said wiper to engage the said i contacts. y
y 6. A device of the character described including a plurality of stationary contacts, a movable contact for engagement therewith, a mounting panel for supporting said stationary contacts and said movable contact, means for operating said movable contact to cause it to engage'said stationary contacts, and means comprising a studsecured to the outermost end of said movable contact and a plurality of orifices in said mounting panel, said stud co-operating with the portions between said orifices for disengaging said movable contact from one of said stationary contacts when it is being moved therefrom to an adjacent stationary contact.
'7o. A .device of the character described in cluding a plurality of stationary contacts, a movable Contact having an intermediate raised portion for engagement with said sta tionary contacts,a mounting panel for supreo` 4 y l l l Y 1,890,721
porting Said @stationary contacts and `said 'movable Contact, and means on 'said panel cooperating with, avstud securedto thel outermost end of said movable contaetto raise saidy Y C 5 movable Contact from engagement with said stationary contacts when being moved from one thereof to another.' j l Y A Signed by Ine at Chica o, in the county of Cook and Stateof I1lino1's, this 15th day of W0 June,A 1925. Y Y .Y A I-IIRAM D. CURRIER.
. l F40 l Y
US37634A 1925-06-17 1925-06-17 Tuning apparatus Expired - Lifetime US1890721A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2798906A (en) * 1953-03-19 1957-07-09 Gen Motors Corp Indicator switch

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2798906A (en) * 1953-03-19 1957-07-09 Gen Motors Corp Indicator switch

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