Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS1837678 A
Publication typeGrant
Publication dateDec 22, 1931
Filing dateFeb 14, 1929
Priority dateSep 12, 1928
Publication numberUS 1837678 A, US 1837678A, US-A-1837678, US1837678 A, US1837678A
InventorsCharles Ryder Samuel
Original AssigneeCharles Ryder Samuel
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Inductance coil particularly adapted for use with radio tuning devices
US 1837678 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Dec. 22, 1931. s. c. RYDER 1,837,678


fawn 44405! l azrjes 2 2 7 Patented 1931 i I UNITED STATES PATENT OFFICE m1. cmmas RYDER, or man, maw sourn WALES, ausraamn mnuc'rmca con. rnnrrcunmr anar'rma, ron. can wrrrr mm mum nnvrcns 1 Application am February 14, 1920, Serial No.

mum self-capacity between its adjacent turns or coils.

'A further object is to provide an induc- 1 tance coil of low self-capacity but having an extensive surface area to thus provide a lower resistance to radio-frequency or high-*frequency currents than is obtainable in inducglc wire of circular cross-section.

A further object of the invention is to pro- 4 vide an inductance coil of low self-capacity and high inductance whose magnetic field is, by virtue of the particular form and design of the coil, restricted to a comparatively small space, this feature being particularly desirable where two or more tuned circuits are incorporated in a radio-receiving set.

The improved coil construction is characterized-in that it is not wound, but has its coils formed by a thin conducting layer of spiral configuration applied by printing, 7 gold blocking, painting, metal spraying or electro-deposition or equivalent means to the 30 surface of a dielectric base, such as bakelite,

celluloid, mica, etc. 7.

'Alternatively, the coils may be self-sup-- porting and produced by any of the known methods of mould or die casting, mechanical cutting, stamping from sheet metal or the like. i

The accompanying drawing illustrates a plan or face view of one preferred form of the improved inductance coil. This coil comprises a base member 2 of di-electric material, such as ebonite or treated paper, having a thin conducting layer applied on its upper surface in such a manner as to form a coil 3 of spiral configuration. This coil may be produced in various Ways.

According to one method, a printing block is first made to print a spiral having the desired dimensions, and an impression from this block is made upon the di-electric base 2 in gold size or similar adhesive substance;

tance coils of present types wound from sin- 389,999, and in Australia September 19, 1928.

A sheet of metallic leaf, such as gold leaf or silver leaf, is now placed over the impression thus formed and is caused to adhere to the portions of the base 2 treated with the gold size or adhesive. The metallic leaf covering those port-ions of the base not coated with gold size or adhesive is now removed by rubbing lightly or similar procedure, thus leaving the spiral coil 3 reproduced on the base a stencil, or electro-depositin processes.

The coil has a central rt1on 4 and an extended end portion 5 hot adapted to receive terminals of any approved type or to make contact as with another circuit. If desired,

suitable taps may be provided in the length of the spiral coil 3 to enable the same to be used as a tapped inductance.

The spiral coil 3 of the improved inductance coil is characterized by having very thin edges of metal presented towards each other between the adjacent turns or coils. Consequently, the inherent or self-capacity of the coil is very low. By reason of the extensive surface area of the turns of the spiral coil 3, a very low resistance is offered to highfrequency currents and a much more confined magnetic field exists as compared with existing types of coils wound with wire of circular cross-section. These advantages are of considerable importance when the improved inductance coil is used in radio apparatus. The extensive surface area of the improved coil enables two or more of said coils to be used very efiectively for close coupling radio circuits similarly to honeycomb, duo-lateral and like types of coils. In this form, the coils are fitted together fiatwise, and, if desired, means may be provided for'varying Other methods may be their proximity to thus vary the degree of capacitive'and inductive cou ling.

Similarly, two or more 0 the improved coils may be connected in series, and means may be provided for varying their proximity to thus obtain a variometer eifect, or alternatively may be inductively coupled as in a vario-coupler or radio-frequency transformer, the degree of capacitive and inductive coupling being readily variable.

In the manufacture of the improved inductance coil, the number of turns in the spiral 3 and the surface area of the turns are variable as found desirable to provide any required inductance-capacity value ac cording to the particular circuit in which the coil is to be used.

The improved coil is of such character that it is eminently adaptable to mass production whereby it can be manufactured much more economically to a predetermined definite electrical standard than can coils of ordinary types produced by wire winding operations, thus ensuring a standard of interchangeability or duplication of circuits not hitherto possible.

It will be seen that the invention provides a form of coil which-particularly when two or more of the same are together usedby virtue of its special design and the thin edgeto-edge disposition of its turns, isolates its inherent or self-capacity from its natural inductance, and its said self-capacity and inductance may be said to have been thus sep arately lumped in a manner which renders them nevertheless arranged so to be each active and capable of being readily adapted for use with a tuned radio circuit whose tuning is effected by the sum product of, and ratio between, its capacity and inductance.

A few adaptations for the use of an improved coil or coils according to the invention, it is thought, may with advantage be mentioned herein and by virtue of the partlcular construction of a coil according to the invention and its particular characteristics as before-mentioned, many other special applications other than hereinafter dealt with will suggest themselves to those persons who are familiar with the art of designing radio and electrical components or circuits.

For example, a coil according to the invention may function as a wavemeter coil where the essentials are an interchangeable coil of low self-capacity and non-variable inductance to facilitate standard calibration.

Again, a coil according to the invention may function as a radio frequency choke Where low self-distributed capacity, a confined magnetic field and a low volt turns ratio are absolutely necessary. To effect this it is usual to wind a solenoid coil of small diameter in several sections or pies. It will be seen that the design of the improved coil lends itself readily to the construction Of a unit where these conditions obtain. A number of coils are connected in series and spaced to form the sections or pies. The connectionsfrom segment to segment or pie to pie may be made by a simple snap-in method, and thusthe inductance of the choke is governed by the number of pies. This flexibility is a desirable feature when changing from upper to lower wave bands.

Again, a coil according to the invention may function as a wavetrap where a coil and condenser are imposed in the aerial circuit and tuned to the frequency of the unwanted signal by the variable capacity.

In utilizing the improved coil, two or more are connected in series, the capacity across them varying as their proximity to each other varies. A suitable aerial tapping is taken from the intersection between coils.

Again, a number of coils according to the invention may together function as a radio frequency transformer where a primary winding is inductively and capacitivel coupled to a secondary winding. These win ings may be fixedly tuned by virtue of the degree of coupling and turn ratio, or alternatively the primary or secondary, or both, may be capacitively tuned to vary the frequency response. In applying the improved coils a very flexible transformer results, the tuning being eiiectcd by the degree of coupling between primary and secondary and the amount of capacity introduced across the secondary; these factors being controlled by a variable position of the coils in respect to each other.

It is of course essential that the secondary be composed of at least two sections to obtain variable capacity across same.

Again, astatic and non-inductive coils may be made by superimposing one spiral upon another-such as for example by using a double-cut spiralthe inner ends being connected together and the outer ends being the beginning and end respectively of the cir cuit. Alternatively, two coils may be con nected together so that their individual fields are opposed to each other.

Still again, where, as in fixedly tuned circuits, the best capacity and inductance ratio for a given wavelength are predeterm ned by the number of turns and effective surface area of two or more of the improved coils in respect to each other, the wavelength response of such a unit may be accurately checked and adjusted with a wavemeter and then sealed in wax, resin or similar insulator.

A number of popular wavelengths may be made up and incorporated in a receiving set where the selection of the wanted station is effected by the simple expedient of switching the suitable unit into circuit.

Again, where, as in balanced circuits, it is necessary to repeat a value of inductance and capacity, the method of manufacture and 17 ctiiistruction of the improved coil automatically repeats the physical and electrical properties of each coil. Further it is possible to readily find the exact electrical centre of an inductance by joining two coils in series and tapping at the intersection.

What I do claim is 1. An inductance coil designed primarilyfor use with radio tuning devices, consisting of a dielectric base having a conducting layer of spiral configuration printed thereon in metallic ink.

2. An inductance coil according to claim 1, in which the printed coil has a central portion and an extended end portion to make contact with another circuit or to receive terminals.

In testimony whereof I afiix my signature.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2427144 *Nov 23, 1936Sep 9, 1947Jansen Franciscus Jo WilhelmusMechanical connection for electrical circuits
US2451725 *Jul 28, 1945Oct 19, 1948Jacob PosterMethod of making a structural unit
US2474988 *Aug 16, 1944Jul 5, 1949Sargrove John AdolphMethod of manufacturing electrical network circuits
US2542726 *Jun 30, 1945Feb 20, 1951Herbert W SullivanMethod of forming inductor coils
US2583854 *Oct 5, 1949Jan 29, 1952Siemens AgInductance coil with ceramic form for high frequency
US2599710 *Aug 7, 1946Jun 10, 1952Albert M HathawayMethod of making electrical wiring
US2601338 *Oct 31, 1947Jun 24, 1952Steatite Res CorpVarialbe parallel resonant circuit
US2611040 *Jun 23, 1947Sep 16, 1952Brunetti CledoNonplanar printed circuits and structural unit
US2622238 *Apr 7, 1949Dec 16, 1952Hannah BoltsonResonant tank circuit for diathermy apparatus or the like
US2649513 *Mar 8, 1949Aug 18, 1953IbmDistributor and method for making the same
US2688649 *Dec 14, 1951Sep 7, 1954Bjorksten Res Lab For ElectrocPrinted battery and method for making
US2721152 *Nov 10, 1949Oct 18, 1955Ward Blenkinsop & Co LtdProduction of electrical elements
US2776235 *Sep 18, 1952Jan 1, 1957Sprague Electric CoElectric circuit printing
US2786187 *Apr 6, 1950Mar 19, 1957Chrysler CorpElectrical coil
US2850707 *Apr 15, 1954Sep 2, 1958Sylvania Electric ProdElectromagnetic coils
US2850709 *Apr 28, 1954Sep 2, 1958Int Standard Electric CorpHigh frequency electric transformers
US2851380 *Feb 9, 1953Sep 9, 1958Woodmont Products IncConductive ink and article coated therewith
US2886880 *May 26, 1952May 19, 1959Hermoplast LtdMethod of producing electric circuit components
US2913724 *Jan 25, 1955Nov 17, 1959Dynamics Corp AmericaAntenna coupling device
US2913725 *Feb 7, 1956Nov 17, 1959Dynamics Corp AmericaAntenna coupling apparatus
US2979615 *Nov 6, 1956Apr 11, 1961Liberty Mfg CorpApparatus for tuning a radio frequency
US2981611 *Mar 12, 1957Apr 25, 1961Metropolitanvickers ElectricalManufacture of printed electrical circuits or components
US3046358 *Dec 23, 1955Jul 24, 1962Comerci Frank ANon-magnetic pickup loop for making absolute measurement of signal strength on magnetic recordings
US3068435 *Apr 19, 1954Dec 11, 1962Sylvania Electric ProdElectromagnetic coils
US3091734 *Nov 7, 1960May 28, 1963Electronic Devices CorpTransceiver construction
US3508457 *Sep 27, 1967Apr 28, 1970Us NavyProcess for constructing thin film inductors
US3515979 *Nov 4, 1957Jun 2, 1970Perkin Elmer CorpMagnetic field control apparatus
US4114428 *Sep 24, 1976Sep 19, 1978Popenoe Charles HRadio-frequency tuned-circuit microdisplacement transducer
US5963871 *Oct 4, 1996Oct 5, 1999Telefonaktiebolaget Lm EricssonRetractable multi-band antennas
US6166694 *Jul 9, 1998Dec 26, 2000Telefonaktiebolaget Lm Ericsson (Publ)Printed twin spiral dual band antenna
US6329962Aug 4, 1998Dec 11, 2001Telefonaktiebolaget Lm Ericsson (Publ)Multiple band, multiple branch antenna for mobile phone
US6343208Dec 16, 1998Jan 29, 2002Telefonaktiebolaget Lm Ericsson (Publ)Printed multi-band patch antenna
US6353443Jul 9, 1998Mar 5, 2002Telefonaktiebolaget Lm Ericsson (Publ)Miniature printed spiral antenna for mobile terminals
US7250868Mar 8, 2005Jul 31, 2007A K Stamping Co. Inc.Manufacture of RFID tags and intermediate products therefor
US20050198811 *Mar 8, 2005Sep 15, 2005A K Stamping Co. Inc.Manufacture of RFID tags and intermediate products therefor
USRE30183 *Oct 16, 1978Jan 8, 1980 Radio-frequency tuned-circuit microdisplacement transducer
DE972477C *Jun 2, 1942Jul 30, 1959Siemens AgAus Isolierstoff bestehende Schaltplatte mit aus leitendem Lack bestehenden elektrischen Verbindungen
U.S. Classification336/200, 29/602.1, 191/1.00R, 336/205, 101/491, 336/232, 29/874, 343/866, 82/1.11
International ClassificationH01F17/00
Cooperative ClassificationH01F17/0006
European ClassificationH01F17/00A