US2611120A - Magnetic cross valve having selfstarting characteristics - Google Patents

Description

Sept. 16, 1952 H. J. MQCREARY 2,611,120

MAGNEITiIC CROSS VALVE HAVING SELF-STARTING CHARACTERISTICS Original Filed June 21, 1950 FIG. I

OUTPUT 2o CY.

INPUT 130v so CY.

OUTPUT 20 cm INPUT 130v eo'cx OUTPUT 2o CY.

INPUT. 130v. so on IN V EN TOR. HAROLD J. M CREARY ATTORNEY Patented Sept. 16, 1952 MAGNETIC CROSS VALVE HAVING SELF- STARTING CHARACTERISTICS Harold J. McCreary, Lombard, Ill., assignor to Automatic Electric Laboratories, Inc., Chicago, 111., a corporation of Delaware Original application June 21, 1950, Serial No. 169,489. Divided and this application January 17, 1951, Serial No. 206,377

4 Claims. (Cl. 32168) This invention relates in general to frequency changers, and more particularly to a means for deriving current of one frequency from a source of current of a different frequency.

An object of the present invention is to provide a sub-frequency generator of the magnetic cross valve type having saturating windings coupled to the primary Winding for providing a biasing flux.

Another object of the present invention is to provide a sub-frequency generator of the magnetic cross valve type having self -starting characteristics wherein circuit means coupled to the input current source provide a direct current biasing flux. 7

Another object of the present invention is to provide a sub-frequency generator of the magnetic cross valve type having a permanent magnet providing biasing flux in order to provide self-starting characteristics.

Other objects of the invention will appear upon a further perusal of the specification taken in conjunction with the accompanying drawings which illustrate several of the embodiments of the invention in the form of schematic diagrams.

Fig. 1 is a diagrammatic representation of a magnetic cross valve sub-frequency generator using permanent magnets to provide a biasing flux at the center of the magnetic cross valve core.

Fig. 2 is a diagrammatic representation of a magnetic cross valve sub-frequency generator in which the leg coils produce a biasing flux by rectifying the input signal.

Fig. 3 is a diagrammatic representation of'a magnetic cross valve sub-frequency generator having a biasing flux produced by using low voltage rectifiers to rectify current flow through a winding coupled to the primary winding.

This application is a divisional application of now pending application for Magnetic Frequency Divider, filed June 21, 1950, Serial No. 169,489.

In the magnetic cross valve systems of the type herein used two windings are displaced by 90 degrees so as to provide that the mutual inductance between the respective windings is substantially zero at partial saturation, but which induces odd harmonics in the secondary winding at high degrees of saturation.

In the present invention, additional saturating windings arewound around the legs of the cross valve to provide D. C. flux to bias the cross valve to a point close to saturation and thereby provide a self-starting system. The additional saturating windings are coupled to the input current source.

In addition thereto, a cross coil is provided to provide a differential flux. The frequency of the cross coil added to the frequency of the secondary winding will equal the input signal. The oscillating frequency of the cross coil is caused by a flux diiferential between the D. C. saturating flux and the flux produced by the input signal. The oscillating frequency for the output winding is provided by'the saturating flux and the flux provided by the oscillation of the cross coil. 'In one embodiment, a permanent magnet used to provide the saturating flux and the cross coil will provide an alternating current to produce an alternating flux, which is superimposed on the D. C. flux produced by the permanent magnet,

Referring now to Fig. 1, a cross valve I0 herein provided may be of the type shown in Patent No. 2,455,078 issued on November 30, 19918, to the present inventor, Patent No. 2,461,992, issued on February 15, 1949, to the present inventor, and Patent No. 2,455,857, issued on July 27, 1948, to the present inventor. The cross valve has two intersecting members. An air gap is shown'at two points alternately opposite the horizontal intersecting member. Permanent magnet H is shown extending from the horizontal intersecting member to the top of the cross valve. Another permanent magnet 12 is shown extending from the other end of the horizontal intersecting member to the bottom of the cross valve II]. The primary winding I3 is wound through opposite dia gonal corners of the intersecting members. Serially connected to the primary winding I3 are two additional windings I4 and I5. Winding I4 is wound around one intersecting member and winding I5 is wound around the other intersecting member. The power supply providing 130 volts at cycles energizes the primary winding I3 and the two additional windings I4 and I5. Cross winding I 6 is wound through the other diagonal corners of the intersection of the cross valve In. The cross winding I6 is displaced degrees from the primary windin I 3. Condenser I1 is connected to the cross winding Hi to provide a resonant circuit. The output circuit comprises two secondary windings I8 and I9 and the condenser 20. The winding I8 is wound around the same intersecting member as is the additional winding I 4, but at an opposite point. The secondary winding I9 is wound around the same intersecting member as is additional winding I5, but at an opposite point. The output circuit comprising condenser 20 and secondary windings I8 .and I9 is tuned to the output frequency at 20 cycles. In more detail, a volt 60 cycle power supply energizes the additional windings I4 and I5 and the primary winding I3. The permanent magnets H and I2 produce all C. saturating flux in the core of the cross valve i ii. The differential flux produced by the D. C, saturating flux and the alternatingfiux produced by the primary winding l3 induces avoltage in the resonating cir=- cuit comprisin the cross coil and the condenser H. The circuit including cross coil l6 and the condenser I? is tuned to 40 cycles. Itis to be noted that there is no mutual inductancebetween the coil 16 and the coil i3, until the mag netic core Iii has reached a pointofnearsaturation which is produced by the D. C. magnetizing flux.

A voltage is now produced in the secondary windings I8 and IQ of the-output circuit. The

induced voltage is producedby a fiux differential caused by the D. C'. saturating flux produced by the permanent magnets H and i2 and the alternating flux produced by the winding 26. As a result thereof. a..20. cycle voltage is induced in the windingsl8 and I9, since a resonating circuit comprising. theserespective windings and the condenser 2li-is tunedfor. that frequency. The 20 cycleirequency of theoutputwinding plus the -40, -cycle.frequency of the cross winding equals ,the 60. cycle input frequency of th'eprimary winding.

Referringnow to Fig. 2,,a cross valve 2| herein usedmay be. of the type disclosed in the previously mentioned patents. The crossvalve has two intersecting members forming two pair of diagonally opposite corners. A primary winding .22 is. wound diagonally through. two corners. of

. ing inductance coil 28, condenser 29, and rectifier 30. A cross winding Si is wound around the other diagonal corners of the intersection of the cross valve 2!. Condenser 32 is connected to the cross winding, to provide a resonating circuit. The output circuit comprises condenser 33 and secondary windings 34 and 35. Secondary winding 34 is wound around the same intersecting member as is'auxiliary'winding 24, but at an opposite end. Secondary winding 35 is wound around the same intersecting member as is auxiliary winding 23, but at an opposite end. The-condenser 33 provides' a resonating circuit with the secondary windings 34 and 35 to oscillate at 20 cycles. In more detail, the 130 volt 60 cycle power supply energizes the primary winding '22 and the auxiliary windings 23 and 24 over the following path: power supply, auxiliary winding 23, primary winding 22, auxiliary winding 24 and back to the power supply. A direct current is produced in ithe-auxiliary winding 23 by the rectifying circuit over "the following path: rectifier 27, auxiliary winding '23, inductancecoil 25 and backto the rectifier 21. In a similar manner direct current is -produced in'the auxiliary winding '24 over the following path: rectifier 30, inductance 'coil' 28, auxiliary winding'24 and backto the rectifier 30. Coil 22 is so wound as to have twice thenumber of turnsof either'coil 23 or coil 24. Additional fiux, over and above the flux produced in the intersecting 'members by the leg coils 23 and 24. is

produced in'the intersecting members by coil 22.

This-"additional. fiuxdncluces voltages in the leg coils 23 and '24, and the additional current in leg coils 23 and 24 has a low impedance path through the aforementioned rectifying circuits. The rectified current in the auxiliary coils 23 and 24 produces D.C. magnetizing .fiuxes' which are opposing-one another. As'a result thereof, voltage is induced in the cross winding 3| by a differential "fiux produced by the 'fiux of the primary winding ofthe-coil 22 and the D. C. saturating flux produced by the auxiliary windings 23 and 24. The circuit comprising the cross coil 3i and condenser 32 oscillates at 40 cycles.

.A voltage is now induced in the secondary windings 34 and 35 which is caused by a differentialiiux Thisdifierential fiux is produced by the D. C. saturatingflux provided by the auxiliary windingsZii and '24 and alternating fiux provided bythecross winding 3 l. The output circuit, comprising secondary windings 34 and 35 and condenser 33, oscillates at the tuned frequency 2!) cycles; 7/

Referring now to Fig. 3 which is a schematic diagram showing'how a D. C. field can'be produced using a low voltage rectifier on the leg coils. Cross valve 56 herein used may be of the type disclosed in said previously mentionedpatents. The cross valvehas two intersecting members forming two pairof opposite diagonal corners. An input winding 31 is wound through a pairof the opposite diagonal corners at the intersection. serially connected to the primary winding 31 are two auxiliary windings 3B and 39. Auxiliary winding 38 is wound around one of the intersecting members, while winding 39 is wound around the other intersecting member. saturating winding 40 is wound on the same intersecting member as is wound auxiliary winding 38. In a similar manner, the saturating winding M is wound around the same intersecting member 'as is wound the auxiliary winding 39. Additional winding 42 is wound through the same diagonal corners as is wound the primary winding 31. The primary winding 31 and the additional winding 42 are magnetically coupled. A circuit comprising'rectifiers 43, 44, 45, 46 and condenser dlconnects the saturating windings ell and 4! with the additionalwinding 42. The cross winding'48 is wound through the other opposite diagonal corners of thelntersection and'is displaced degrees from the primary winding '31. A condenser 49 forms an oscillating circuit with the-cross winding 48 to oscillate at 40' cycles. The output circuit comprises. secondary windings 50 and 5! and the condenser 52 and is tunedto 20 cycles. The secondary winding bli is wound aroundthe same intersecting member as is auxiliary winding 39, but at an opposite point. The secondary winding 5! is wound aroundthe same intersecting member. as is auxiliary winding'38, but. at an opposite point. In more detail, the power supply providing volts at 60 cyclesenergizes theauxiliary windings 38 and 39 and the primary winding 3?. The additional winding 42 is magnetical- 1y. coupled to the primary winding S'l'and thereby a voltageis inducedin the additional winding. As a result thereof, a rectified voltage is produced in the saturating windings 4i] and 4| over the following path: additional winding 42, rectifier 4E5, saturating winding 40, saturating-winding 4|, rectifier 44" and back to the additional winding 42. The saturating windings'40 and'4l produce a D. C. saturating flux for the cross. valve 36, thereby providing a biasingfiux. Voltage-is induced in thecrosstwinding 48.. by a difierential fiux'p'roduced by the D. C. saturating flux and an alternating flux. The D. C. saturating flux which is a biasing flux is produced by the windings 4a and 4|. The alternating current flux is produced by the windings 39, 38 and 3!. Since the cross winding 48 is tuned to 40 cycles by the con.- denser 49, that circuit will oscillate at the desired frequency. As a result thereof, voltage is induced in the secondary windings 59 and 5| which is caused by a difierential flux. The differential flux is produced by the D. C. magnetizing flux and the alternating current flow. The last mentioned D. C. saturating flux is provided by the saturating windings 45] and 4! and the alternating current flux is produced by the cross winding 48. the secondary windings 50 and 5t, to oscillate at 20 cycles, the output frequency derived from this system is a 20 cycle signal.

Although I have described my invention with a certain degree of particularlity it should be understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the completion and arrangement of parts may be resorted to without departing from the true spirit Since the condenser 52 is tuned with and scope of the invention as hereinafter claimed.

What is claimed is: 1. In a static frequency changer, a saturable magnetic core having a pair of intersecting mem hers, a primary winding wound through one pair of diagonally opposite corners of the intersection, a secondary circuit including a condenser and a coil wound around said pair of intersecting members, a source of alternating current con nected to said primary winding for providing the input signal, said input signal producing an input flux in said core, a load circuit connected to said secondary circuit, a permanent magnet disposed about said magnetic core for providing a biasing flux in said core, and a cross winding wound through the other pair of diagonally opposite corners of said intersection, a condenser connected across said cross winding forming a resonant circuit, said resonant circuit resonating responsive to said input flux and said biasing flux to produce a differential flux in said core, whereby alternating currents having a frequency integrally related to the frequency of said source is delivered to said load circuit.

2. In a frequency changer, a magnetic core structure having two intersecting members, a primary circuit including a coil wound through a pair of diagonal corners of the intersection, a source of alternating current for energizing said primary circuit to provide the input signal, a secondary circuit including a condenser and a coil wound around the two intersecting members and tuned to the desired output frequency, a pair of permanent magnets disposed at diagonally opposite positions of said magnetic core structure to provide a biasing flux in said magnetic core structure, a differential circuit tuned to an intermediate frequency and having a condenser and a coil wound through the other pair of diagonal currents to provide continuous oscillating current in response to the flux differential produced by the 6 biasing flux of said permanent magnets and the differential flux of said primary circuit, said secondary circuit oscillates to the tuned frequency in response to the flux differential set up by said differential circuit and the biasing flux of said permanent magnets, thereby providing selfstarting characteristics.

3. In a frequency changer, a magnetic core structure having two intersecting members, a primary circuit including a coil wound through a pair of opposite diagonal corners of the intersection, a source of alternating current of a certain frequency for energizing said primary circuit to provide an input signal, said input signal producing an input flux in said core, a pair of permanent magnets disposed about said magnetic core structure to provide a biasing flux for said magnetic core structure, and an output winding having a load circuit connected thereto and wound through the other pair of diagonal corners of said intersection, said output winding having a condenser connected thereacross, thereby forming a circuit resonant to a certain output frequency, another resonant circuit comprising a condenser and a coil wound about the other pair of opposite diagonal corners of the intersection and resonant at a frequency which is the dinerence between the aforementioned frequencies, said last mentioned circuit resonating responsive to the input flux and the biasing flux for producing a differentiai fiux in said core, whereby a1 ternating currents are produced in said load circuit in response to the biasing flux produced by said permanent magnets and the differential flux produced by said primary winding, thereby providing self-starting characteristics.

4. In a frequency changer, a magnetic core structure having two intersecting members, a primary winding wound through a pair of opposite diagonal corners of the intersection, a source of alternating current of a certain frequency for energizing said primary winding to provide an input signal, said input signal inducing input fluxes of odd harmonics of said input signal frequency in said core when said core is saturated by a biasing flux, an output winding wound around said intersecting members, a condenser connected across said output winding forming a circuit resonant at a sub-harmonic frequency of said input signal, a load circuit connected to said secondary Winding, resonating means associated with said core for producing a differential fiux in said core of a frequency which is the difference between said input frequency and said subharmonic frequency, and a pair of permanent magnets disposed about said magnetic core for providing a biasing flux in said magnetic core, whereby alternating currents of said subharmonic frequency are produced in said load circuit, thereby providing self-starting characteristics.

HAROLD J. MCCREARY.

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

UNITED STATES PATENTS Number

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