US1173679A - System for producing high-frequency oscillations. - Google Patents

Description

M. OSNOS.

SYSTEM FOR PRODUCING HIGH FREQUENCY OSCILLATIONS.

APPLICAHON HLED FEB. 3,'I914.

1,178,679. "Patented Feb. 29, 1916.

M/ITTNES'EE'S'. Z/VVENTURI fl/lzyzz 575N475,

H7514 TTURNEx MENDEL OSNOS, OF fiEB/LIN, GERMANY, ASSIGNOR T0 GENERAL ELECTRIC COMPANY,

A CORPORATION OF NEW YORK.

SYSTEM FOR PRODUCING HIGH-FREQUENCY OSCILLATIONS. I

Specification of Letters Patent. Patented Feb. 29,1916.

Application filed February 3,1914. Serial No. 816,191.

T 0 all whom it may concern:

Be it known that I, MENDEL OSN-OS, a subject of the Czar of Russia, residing at Berlin, Germany, have invented certain new and useful Improvements in Systems for- Producing High-Frequency Oscillations, of which the following is a specification.

' danger to the'appara'tus and without exces- I pose, by my sive wear. Such installations use motorgenerator sets for the production of high;

frequencycurrents, and various diiiic'u'lties have been encountered with the arrangements used for causing the oscillations. When the work circuit from the alternating current machine is broken or short circuited by'the operating, key, certain-high voltages or heavy currents are set up which, may readily do harm to the apparatus. The short circuiting currents will be especially large if the machine has anair gap of normal or large size. Further, such voltages and currents necessarily cause' a sparking at the operating key which soon destroys its contacts. Similarly, if the operating key be used to short circuit the shunt field of the generator, the high inductance of this field willgive rise to excessive sparking at the contacts of the key. Accordingly, I proinvention, to provide such an arrangement of the transmitting apparatus in a system for producing high frequency oscillations, that its operation will be attended with as little danger as possible, and

that satisfactory operation will be had withp out excessive wear on the apparatus involved.- To attain these results I provide the alternator which supplies energy to such a system with afield winding of low inductance, preferably excited from the mains of I the driving motor and arranged in series with said motor, and connect ing. When this short circuit is altered the increased flux on the machine will produce a-voltage suflicient to jump the spark gap and cause an oscillation. In the preferre form of my invention I .also'supply the Interposed in the latter circuit is the motor.

circuit around the the operating keyas a short circuit around this field wind.-

alternator with a second field winding for furnishing part of the excitation.-

In the accompanying drawing the single figure shows diagrammatically the circuit of .a transmitting apparatus of a wireless telegraph station arranged according to my The showing of the work circuit, 3 is wholly diagrammatic and is intended to be typical of that n common use forwireless telegraphy, as any arrangement of this circuit may be'used in a system embodying my invention. For this purpose I have indicated the alternating current generator as connected to the primary of a step-up transformer 10 whose secondary is connected to the primary of a step-up transformer 11. usual spark gap 12,. while a condenser 13 is bridged across the secondary of the transformer 10. One terminal of the secondary of the transformer 11 is shown as connected to ground at 1%, while its other terminal .is

connectedto .a circuit 15 leading to suitable.

antennae.

The motor-generator set 1 comprises a direct current motor 20 having a shunt field winding 21 and supplied with power from the direct currentmains 2. high frequency alternator with armature winding 22 is driven by this motonf'The alternator has two field windings 23 and 24, the

former being in shunt across the mains 2,

while the latter is a low inductance wind ing which may be placed in series with the In circuit with the/field winding 23 is a suitable'rheostat 25.

In shunt with the series field winding 24: I'provide an operating seen by an inspection of the drawing, this key it's-normallyw closed andform's-a short series field winding. When the key is depressed against the action of the spring this short circuit will be removed.

The operation of my arrangement will be as foll0w s-:The rheostat 25 will first be so adjusted that the excitation of the field d winding 28 Wlll produce such a voltage in' the armature 22 that after transformation at key 30. As will be 10 it will not be quite enough to cause a spark across the gap 12. It will then be seen that when the operating key 00 is depressed the series field winding 24 will give an added excitation for the alternator. This will be sul'licient to raise the voltage so that it will jump the gap 12 and produce an oscillation at the antennae. The key being released, the series field winding ll will he again short circuited and the voltage of the alternator decreased. By such an arrangement I am enabled to obtain. the results desired. Since the series field winding supplies only a portion of the excitatiolnit need have but a comparatively small number of turns and hence will be of small inductance. Because of the inherent characteristics of a serieswinding, its inductance will be small whether it he used alone or in coniunction with a second winding. Consequently, the sparking at the contacts of the operating key will be reduced to a minimum. Further, since we are neither opening nor short circuiting'the work or armature circuit, the alternator will not be endangered.

Although I have described herein the best embodiment of the invention now known to me, I do not wish to be limited to the exact details shown, but seek to cover in the appended claims all those modifications which cr me within the scope and spirit vof my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. A wireless signaling system including an antenna, means operatively related to said antenna for producing high frequency oscillations, said means comprising an alternating current generator, a direct current motor for driving the same, said generator having a field winding in series with its motor, and n'ieans for varying the voltage delivered by said generator to induce electrical oscillations in said antenna. in accordance with the signals to be transmitted,

comprising means for opening and closing a short circuit around said series field winding. l

2. A wireless signaling system including an antenna, means operatively related to said antenna for producing high frequency oscillations, said means comprising an alternating current gcne'ator and a direct current motor for driving the same, the generator beingprovided with two field windings, one of said field windings being connected in series with said motor, and the other field winding being excited from a constant potential source, and means for quickly" varying the flux produced by said series field winding to therebyvary the voltage of said machine and induce an electrical oscillation in said antenna 3. A system for producing high frequency oscillations, including a transmitting mechanism, said mechanism comprising an alternating current generator, a direct current motor for driving the same, the generator having a field winding connected in shuntrelation to said motor and another field oscillations, including a transmitting mechanism, said mechanism comprising an alternating current generator, a direct current motor for driving the same, the generator having a field winding connected in shunt relation to said motor and another field winding connected in series with said motor,

and means for short circuiting said series field winding.

In witness whereof, I have hereunto set my hand this 16th day of January, 1914.

MENDEL ()SNOS.

Vitnesses RICHARD NEUMANN, GUSTAV WERNER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

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