US1224639A - Apparatus for transforming electrical energy. - Google Patents

Description

P. C. HEWITT.

APPARATUS FOR TRANSFORMING ELECTRICAL ENERGY.

APPLICATION FILED .IULY I. I905. RENE'WED OCT. 2, I916.

Patented May 1, 1917.

PETER COOPER HEWITT, or NEW roan, n. Y., nssrenon, BY MESNE assremnrs;

TO COOPER HEWITT ELECTRIC 00., F HOBOKEN, NEW JERSEY, A CORPORATION 01E I NEW JERSEY.

Original application filed June 7, 1905, Serial No. 264,071.

Specification of Letters iatent.

- APPARATUS FOR TRANSFORMING ELECTRICAL ENERGY.

Patente'dltiiay l, 1191?.

Serial No. 267,982. Renewed October 2, 1916. Serial No. 128,288.

To all whom it may concern: 1

Be it known that 1, PETER COOPER HEWITT, a citizen of the United States, and resident of New York, county of New York, State of 5 New York, have invented certain new and useful Improvements in Apparatus for Transforming Electrical Energy, of which the following is a specification.

My present invention relates to interrupters, particularly such as have a disintegrating and restrictive negative electrode such as mercury. The invention involves the practical elimination of the negative electrode factor of interruption found in devices of the kind referred to in my prior Patents Nos. 780,999 and 781,000, granted to me on January 31st, 1905, and the bringing into operation and effect of the characteristic resistances and interrupting action of the vapor column, the negative electrode of the discharge being continuously maintained in the broken-down condition. In practice, the effects seem to be almost entirely free from any effect of either negative or positive resistances other than that of a vapor column terminating at one or both ends in 0011- tinuously maintained actively conducting bodies of vapor.

The interrupting'action of the vapor column is particularly efficient in causing very sharp sudden interruptions, especially favorable to the production of high frequency oscillation and abrupt fluctuation. This is very markedly indicated in the practical working of the device and may be accounted for from the simultaneous cooperation of two causes operating separately to produce the same result. The discharge of the condenser through the device being once started the drop in voltage across the latter is approximately constant and the loss therein is nearly proportional to the current. The fall of voltage of the condenser supplying the current and the rise in the voltage necessary to keep the vapor column conducting, act in opposite directions to cut short the flow thereby producing the characteristic abrupt interruption of current flow.

Another valuable characteristic of the vapor column is that its starting and interrupting voltages or resistances vary accord-- ing to functions of the length, density and diameter of the column, being greater for- Divided and this application filed July 1, 1905, Y

progressively of less importance where these are high. Where vaporizable material is present the resistance of the vapor column varies directly as the temperature for all temperatures Whereas the negative electrode I resistance tends toward a constant around say 200 or 300 Fahrenheit.

From the above consideration it will be evident that not only is the interrupting action of the vapor column characteristically abrupt and therefore particularly eflicient but it also lends itself very readily to the practical solution of problems of design for use in particular connections because its length may be extremely small, its diameter great and its density low thus adapting it for use in connection with the lowest voltages. In addition to this the range of high resistances by great length of column and smallfdiameter and higher densities is very wide and limited only by practical considerations.

In the practice of my invention I provide a supplemental electrode adjacent to the negative electrode of the circuit to be interrupted and make said supplemental electrode the positive electrode of an auxiliary local insulated circuit of a source of electromotive force, preferably a storage battery.

The main negative electrode of the lamp I make'the negative electrode of the storage battery circuit. The battery is of suflicient voltage to maintain the current through the vapo'r conductor between the adjacent terminals. This has the effect of maintaining the negative electrode of the circuit to be interrupted in its low resistancesor operating condition, so that there is no negative electrode resistance to starting or practically none at the electrode to oppose the passage of the current to be started and interrupted.

Such an arrangement is unsymmetrical but is suflicient where the current to be .interrupted is direct current and where it is not essential that the condenser discharge be oscillatory. It is evident, however, that where the source is an alternating current source or where the purposes in view require that the condenser discharge be oscillatory, it is preferable that each of the electrodes of the discharge device be provided with an adjacent supplemental electrode and a separate local circuit to maintain a current continuously flowing from such supplemental electrode to the main electrode precisely as hereinbefore described with respect to the first mentioned electrode.

When both electrodes are thus made actively conducting through small portions of the vapor column respectively, the remainder of the vapor column connecting these two zones or regions of activity acts as the interrupter in accordance with its own laws of operation, and free from material complication or modification by electrode resist ance phenomena, in other words, the device is in a sense a symmetrical vapor conductor interrupter having constantly conducting vapor electrodes.

In the accompanying drawings, Figure 1 is aview of a form of my discharge'device with adirect current source, connecting circuits and auxiliary apparatus diagrammatically indicated.

Fig. 2 is a similar view of a modified form of discharge device, adapted for alternating or oscillatory currents, the discharge device being provided with means for maintaining or modifying the temperatures at'the respective electrodes and the intermediate vapor column.

In Fig. 1 a direct current source shown as a direct current generator, supplies the circuit 2, 2. Bridged across this circuit is a condenser 3 in parallel with the discharge device 4. Between the source and the condenser in series may be arranged a reactance 5, preferably an inductance coil ad apted for adjustment to vary its impedance and thereby regulate the rate of supply of current from the source. The condenser 3 is connected to the distant electrodes of the discharge device. If desired, these connections could be made to other points of the supplemental circuits, hereinafter described. The discharge device 4 comprises the two electrode chambers 6 and 7 and the connecting tube 8. The electrode chambers are provided with suitable main electrodes 10 and 11, the negative electrode 10, being of disintegrating material, preferably of mer-- cury. The main positive electrode either 11 or 9, in one end of the tube, and the supplemental positive electrode 12, at the other end of the tube, are preferably of iron, but may be of carbon or other suitable material; or by slightly changing the construction, of mercury or other suitable liquid. These chambers and electrodes may be of the construction and may have substantially thecharacteristics of any of the devices and electrodes which I have described in my prior patents and applications and the construction may be widely varied. The main negative electrode is connected so as to constitute it the negative electrode of a storage battery 14:. The positive lead of said storage battery is connected to the adjacent supplemental positive electrode 12, thus completing a local battery circuit through the vapor in the chamber 7 between the supplemental positive electrode 12 and the main negative electrode 10. Between the main negative electrode and its storage battery is preferably arranged an inductance or resistance, as at 16. The purpose of this inductance is twofold. By reason of its reactance it confines the discharge of the condenser 3 to the electrode 10 and by reason of its ohmic resistance, it serves to retard and control the flow of current from the battery, which might otherwise be excessive by reason of the low resistance of its circuit. The latter function may be served by an ordinary adjustable rheostat. The inductance may serve to compensate for varying resistances at the negative electrode, but this is not necessary to the present invention. lVhere the object of the local battery is solely the elimination of electrode reluctance from the condenser discharge circuit, a storage battery furnishing an electromotive force of about 30 or 40 volts will be sufficient. In such case the resistance of 16 should be about 10 ohms. These figures are subject to considerable variation, but, in practice, I find that somewhere from 1 to 3 amperes. is quite sufficient to maintain current flow through the electrodes 12, 10, thereby eliminating the opposition of negative electrode reluctance to the discharge of condenser 3 through the circuit 13, positive electrode 11, vapor column 8, and negative electrode 10. The current in said battery circuit may be started by any of the methods used to start my mercury vapor lamps.

It will be noted that so far as concerns the initiation of the condenser discharge,

the function of the above described battery circuit is superficiallysomewhat similar to that of my supplemental starting electrode, which I sometimes use to start my mercury vapor lamps and rectifiers. In the present connection there is an entirely different function, which is performed at the instant of interruption or cessation of current flow and which is of great importance. As employed herein, the battery circuit operates continuously to maintain the negative electrode 10 in its broken down state of resistance, so that the negative electrode reluctance does not assert itself at the instant when the interruption occurs. The result is that the interrupting action is solely that of the vapor column 8 with all interrupting action of the negative electrode eliminated. From the above, it will also be understood pend upon capacity, inductance and resistance of the discharge circuit and may be varied by varying the capacityof the condenser 3. or of the length of'wire 13, as diagrammatically indicated at 25.

A device of the kind shown in Fig. 1, is well adapted for interrupting direct current in one direction, and the apparatus may be proportioned and arranged so that the discharge of condenser 3 will be oscillatory, but the oscillations where superposed on the direct current from the source result in intermittent or fluctuating direct current in that portion of the circuit. The latter, whenpassed through the primary of the trans former induce alternating currents or oscillations in the secondary circuit thereof.

In the arrangement shown in Fig. 2, the electrodes at both ends of the vapor column 8 are physically and electrically similar and symmetrical, and are both provided with the supplemental battery circuits, the electrodes 9, 11*, battery 13, and impedance 15 at one end, being respectively similar to 10, 12, 14, and 16 at the other end.

In both .the above described arrangements, the abrupt variations or fluctuations of current may be utilized for wireless telegraphy or any other similar or desired purpose for which such currents are useful, by transfer to an outside circuit 17 by any suitable means, as, for instance, a transformer having its primary 18 in series with the condenser discharge. The circuits 1, 2, and 1 2, may be connected around the condenser 3 and primary 18, as shown in Fig. 2, instead of around the condenser only, as in Fig. 1. The inductance 5 or 5 may be of such value as to restrain the primary current for a suflicient time to permit free discharge and if desired free oscillations of the condenser circuit 3, 25,9, 6, 8, 7, 10, 18, before the recharging of the condenser progresses very far. The frequencies of charge and discharge of the condenser may be the same or different, as desired.

It is not necessary that the interrupter be kept cold, though this is sometimes desirable. It is important, however, to preserve,

uniformity of the surroundings and of the heat radiating rate, as the vapor density is determined by the temperature and this I should be constant so that the operation of the device may be uniform. A hot or cold bath, maintained at the desired temperature, or a non-conducting or conducting jacket of any kind, will serve this purpose. In Fig. "2 such devices are indicated by the inclosure 24 for the vapor column in tube 8 and inclosures 34 and44 for electrodes 9 and 10 respectively.

In addition to the above mentioned variables of length and diameter of tube 8 are other variables including the volume and As has been stated above this inventionenables me to predetermine and fix the interrupting voltage or resistance at any desired value within practical limits.

My interrupter herein described may be readily caused to'efi'ect the interruption at the desired value of falling current and thus render the desired fraction of kinetic energy available for change into potential energy and the oscillations may be made of correspondingly increased persistance up to limits determined by the initial energy of the charge and the rate of dissipation, etc.

I have hereinbefore specified certain voltages as desirable for the storage batteries and certain resistances as desirable for the circuits thereof and have also specified that be always larger than the maximum instantaneous value of flux of the oscillations from the condenser flowing from the negative electrode because, as will be obvious, if at any instant the flux from a negative electrode of the oscillatory circuit becomes equal to or greater than the battery fiow into said electrode, the battery flow will be interrupted and will not reestablish itself. If, however, the amperage of the condenser discharge out of the negative electrode is always small as compared with the storage flow into said electrode, the operation of the device will be continuous. Hence the necessity of carefully considering the keep-alive circuit where oscillations of large amperage are to be handled in the apparatus described herein.

In another application Serial Number 264,071, filed June 7, 1905, of which this application is a division, claims are made upon the method disclosed herein; and in a division hereof filed April 16th, 1915, Serial Number 21,843, claims are made on the invention disclosed in Fig. 1 hereof and, also, generic claims covering Figs. 1 and 2.

I claim as my invention:

1. A gas or vapor device comprising gas or vapor arranged in direct contact with and between bodies of vapor conductor, normally maintained in conducting condition;

ducting column of gas in direct contact withand connecting the same.

4. A capacity circuit, and a long sealed and evacuated container, having pairs of similar electrodes at distant points therein, one electrode of each pair being vaporizable and constituting a discharge terminal of said capacity circuit, in combination with independent insulated sources of direct electromotive force for each pair of terminals, a vaporizable terminal of each pair being the negative electrode of the source to which it is connected.

5. A discharge device comprising two independent continuously operating insulated vapor conductor devices, and a normally non-conducting column of gaseous material in contact with and connecting the same.

6. A discharge device comprising an inclosure and at regions remote from each other pairs of disintegrating and reconstructing electrodes disintegrating and reconstructive in combination with independent sources of electromotive force for each pair of electrodes and a capacity circuit having terminal connection to each of said circuits. 1

7. A discharge device comprising a tube, enlargements or chambers at each end thereof and a pair of electrodes in each chamber, one electrode of each pair being vaporizable and being connected to form a negative electrode of a direct current circuit.

'8. A capacity circuit and an elongated sealed and evacuated container having pairs of electrodes in distant regions thereof, one electrode of each pair including mercury and constituting a discharge terminal of said capacity circuit, in combination with independent insulated sources of direct negative electrode of the source to which it is connected.

10. An electrical circuit in combination with means for modifying the energy of said circuit, said means comprising a gas or vapor path lying between two conducting bodies of gas, each continuously maintained in conducting condition independently of the presence or absence of current flow in the path between them, together with means for utilizing a portion of the energy flowing in said first named means.

11. An electricalsource and an impedance arranged to be traversed by intermittent discharge at intervals short as compared with the duration of supply of energy continuously in one direction from said source, in combination with a discharge gap therefor, comprising a gas or vapor device of the class described, together with means for modifying the reactions at both electrodes, said means comprising connections at each end of said path, operating to cause continuous current flow through said electrodes independently of the presence or absence of current flow in the part of the gas or vapor path utilized at the'discharge gap.

12. An electrical source and a reactance circuit adapted to store up and discharge energy from said source at a definite rate, and during'time periods small as compared with the time during which the energy flows continuously in one direction from said source. in combination with a discharge gap therefor, comprising a gas or vapor device of the class described, proportioned and arranged to operate at relatively high density, together with means for modifying the reactions at both electrodes, said means comprising connections at each end of said path, operating to cause continuous current flow through said electrodes independently of the presence or absence of current flow in the part of the gas or vapor path utilized as the discharge gap.

13. A source of electrical energy and a reactance circuit adapted to be traversed intermittently by said energy at definite intervals, independent of the duration of energy flow in one direction from the source, in combination with a discharge gap in said circuit, comprising a gas or vapor path, and means for modifying the negative electrode reactions at both ends of said path, said means comprising connections for causing continuous current flow into both said negative electrodes independently of the presence or absence of current flow in the part of the vapor ath used as the discharge gap.

14. n a system of electrical distribution containing an inclosed gas or vapor device with electrodes having a high starting resistance which resistance is adapted to be eliminated by current flow, said device also including a portion constituting a vapor path connecting 'the regions of said electrodes, said vapor path being characterized by a high starting resistance which resistance is eliminated on the flow of current and having a voltage current characteristic with rapid rise of voltage for decrease in current, the method of securing rapidly recurring discharges which consists in permanently eliminating the starting resistance of the electrodes, applying electric potential upon a discharge circuit containing an impedance and a condenser and including said device and utilizing the variations of resistance of the vapor column connecting the electrodes to control the oscillations of electric energy in the discharge circuit.

15. In a system of electrical distribution, the combination with a source of electric current, a discharge circuit and an exhausted vapor device connected therewith, of means for utilizing the vapor column of said device unmodified by electrode reactions as a discharge gap, said means including means for eliminating the cathode resistance in the paths of actual discharges.

16. In a system of electrical distribution, the combination with a source of electric current, a discharge circuit and an exhausted vapor device connected therewith, of

means for utilizing the vapor column of said device as distinguished from the electrodes as a discharge gap.

17. A discharge gap comprising an inclosed exhausted vapor apparatus having electrodes characterized by difierent starting and running resistances, and a vapor column connecting said electrodes and characterized by a starting resistance of its own disappearing upon the flow of current and further characterized by a volt-ampere characteristic showing a rapidly rising voltage with decrease of current toward the non- Operating current value, in combination with means for modifying the cathode re sistance or" the electrodes as distingaished from the vapor column.

18. In a system of electrical distribution, the combination with a source of electric current, an intermittently operating series discharge circuit and a vacuum electric device connected thercwith, of constantly active electrodes in the discharge circuit,

Signed at New York, in the county of New York, and State of New York, this 26th day of June A. D. 1905.

PETER COOPER HEWETTG l Vitnesses i -Jar, H. CAPEL, GEORGE E. STOCKBRIDGE,

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