US350958A - Distribution of electric currents - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1. E. THOMSON.

DISTRIBUTION OF ELECTRIC GURRENTS.

No. 350,958. Patented Oct. 19, 1886.

WITNESSES: l/VVE/VTOI? ATTORNEY (No Model.) 2 Sheds-Sheet 2. E. THOMSON.

DISTRIBUTION OF ELECTRIC GURRENTS.

Patented Oct. 19, 1886.

fifflw WITNESSES:

ATTORNEY UNITED STATES PATENT OFFICE.

.FLIHU' THOMSON, OF LYNN, MASSAOHUSET DISTRiBUTlON OF ELECTRiC GURRENTS.

PECIFICATIGI-T forming part of Letters Patent No. 350,958, dated Gocober 3.9, 1886. Application filed February 1, 1886. Serial No. 190,496. (No model.)

To aZZ whom, it may concern:

Be it known that I, ELIHU Tuonsox, a citi zen ot' the United States, and a resident of Lynn, in the county of Essex and State of Massach usetts, have invented certain new and useful Improvements in the Distribution of Electric Currents, of which the following is a specification.

My invention relates pz'u'ticularly to the con struction ofa switching-magnet, designed more especially for use in electric-lighting systems, as a means for controlling an elcctricswiteh, by the agency of which circuits or connections may be automatically formed, so as to preserve the general circuit from rupture or disturbance of its normal resistance or continuity.

My invention relates to means whereby an artificial resistance may be introduced in place o't'an incandescent lamp whenever the filament of the lamp is ruptured, or whenever too high a resistance exists in said lamp, as, for instance, when through extended use the filament has lost a part ofits conducting power.

So far as concerns the switclrmaguet itself, the invention is applicable to any electromagnet used in controlling a switch that affects the circuit in or to which the magnet is connected.

The principal object is to prevent vibration ofthe inagnets armature, and to secure a steady action of the same, so as to render it insensible to quick or sudden but momentary variations of exciting-current.

My invention comprises, also, certain other improvements in the details of the switchingmagnet and in the arrangement of circuits, resistances, translating devices, &c., that will be more particularly specified in the claims, after having been described in connection with the accompanying drawings.

I have herein illustrated my invention as applied to circuits upon which incandescent lamps are employed, the invention being ap plied in such way as to preserve the integrity or continuity of the line, so that other lights or apparatus upon the same line may be practically unaffected in their brilliancy. I do not, however, limit myself to such particular application of my devices and combinations, inasmuch as they are applicable to other translating devices besides incandescent lamps.

In the accompanying drawings I have shown in Figu re 1 the switelling-magnet in longitudr nal section combined with an incandescent lamp and an artificial resistance, R, that is to be substituted for the lamp in case of rupture, or of abnormal resistance in the portion of circuit containing said lamp. The circuits over which current is supplied to the lamp and its adjuncts are indicated by the letters a I).

Fig. 2 illustrates diagrammatically the application of my invention to another condition of working, to wit: one in which a number of circuits fed from the same machine and in multiple arc to one another. Each containsin series a number of incandescent lamps or other translating devices. It is to a system of this kind that my invention is especially applicable, it being in such case especially desirable to keep the resistance of the several circuits constant and to keep each line closed at all times by substituting the resistance R for any incandescent lamp, in case the filament of the same breaks or otters too high a resistance for practical work, or in the event of the lamp falling from its holder or not being inserted into the circuit.

Fig. 3 illustrates a modified form of my switchinganagnet combined with a group of incandescent lamps or other translz'iting devices, and with a group of resistances individuallycqnal to an electric lamp and individuallysubstituted therel'or in succession as the lamps or other branches are taken out of the general circuit by the agency of the armatures for the said magnet. Fig. 4 is a side elevation of the magnet illustrated in Fig. 3. Fig. 5 shows a magnet combined with a switch that opens the circuit to the lamp or other translating device at the same time that it throws into circuit an artificial resistance the equivalent of the resistance presented in the lamp or other translating device when the same is in circuit.

The lamp L, Fig. 1, is placed in the circuit from (t to I) in the ordinary way, said circuit being, if desired, one of a number of branches from a common source or from a common supply-conductor, or otherwise connected with a generator or an electric main. In a branch around said lamp are the coils of a high-re sistance electromagnet, K, whose coils are wound upon a core, (J, of irou,which exerts an attractive effect upon its armaturcA, and upon. an increase 01' its action. to a predetermined amount raises said armature against the stress of its retractor, so that by making contact with a conducting-plate, D, the armature completes a branch circuit around the lamp through an artificial resistance, R, in obvious way. The armature A for said magnet is pivoted in any suitable manner, and connection being made to it, asshown, said magnet-armature forms virtually an electric switch. The armature is provided with a suitable retraetor such as a spring or weight, 'and normally rests against a stop, S. When the armature is drawn up against the plate D, constituting the opposite stop i'or the same, the connection just men tioned is made through the resistance R. The resistance R is ordinarily equal to that of the lamp L. Around the core 0, and at any distance therefrom, is arranged a closed conducting circuit or band of copper or other good conductor, B, which is made of sufficient size to give considerable sluggishness of action.

to the magnet C by its effect in becoming the seat of induced currents which oppose any actions or changes of magnetism or movements of the armature A. Thus should the current in the coil K increase an opposing current will be produced in the band B, and should the current in K decrease a current will be produced in B to keep up the magnetism of the core 0, or retard its loss. Similarly the approach or recession of the armature Ais made deliberately or slowly by virtue of the same actions in the band B, opposing any change of magnetic condition of the core 0, except through an interval of time. I find this action very useful in case of a switching-magnet used to operate switching mechanism, since it prevents undue sensitiveness to quick fluctuations of the current traversing the magnet unless the changes are fairly permanent, or may last for some little interval, as a second or two, and the tendency of the armature to vibrate is in a great measure checked.

The adjustment of the armature A, or the power of the magnet K to attract said armature, is made such that when the lamp has its usual or normal resistance the armature Awill remain down, and when thelamp L is out of circuit or has too high a resistance, the said armature, having been attracted or drawn up, will remain attracted keeping in circuit the resistance It. This condition of adjustment is a very important one, and may be expressed in another way. Assuming the magnet K to have a'normal power, due to the presence of a proper resistance in the lamp L, the armature A must be so adjusted that when away from the magnet it will remain away, and when put toward the magnet (the resistance It'at such time not being in circuit) the said armature shall still remain in its attracted position. The results of such adjustment are that with the devices arranged and connected as in Fig.1 a substitution of the resistance R will take place upon too high a resistance existing in the lamp L, or upon the rupture of its filament, or upon its removal from the circuit, or upon its failure to be introduced. On the introduction of the lamp L there would be two paths for the currentone through the resistance R and one through the lamp L. This willlower the potential at the terminals of the magnet K, and there will result a falling away of the armature A and the removal of the resistance It- It is assumed that the current passing along the line is fairly constant. By this simple arrangement it is possible to operate with success a large number of incandescent lamps in series and in multiple series from the same generating source, as indicated in Fig. 2, each lamp being provided with its switching-magnet, as I have described.

\Vhen it is desired to operate a group of magnets in each derivation of the circuit, and to provide a group of resistances which may be substituted for the lamps on extinguish ment or removal from the circuit of the latter, I modify the arrangement, as shown in Fig. 8. Here the magnet has three armatures, A A A, although two or more may be employed,

and the core of the magnet, although it could be made as a single core or piece, is preferably divided, so as to present a triple core, or acore presenting several poles, in accordance with the number of armatures used. The coil K is wound, as before, around this compound'eore. It is connected in derived circuit around the lamps, and it is of very high resistance, so as to avoid waste. Each armature A A A closes a suitable contact, as in Fig. 1, when attracted, and therebyintroducesaresistance, R, around or in derived circuit with thelamps LL, which are in a parallel group or in multiple are, as shown. The adjustment of the armatures is, as before, such that with a normal energizing of the magnet K, and with the resistances R R R open-circuited, said armatures would remain either away from the magnet-cores or remain attracted in position that is, the increase of magnetic pull due to the approach of said armatures to the core would hold them near the cores, and on. pulling off the arma tures from the cores the consequent decrease would cause said 'armatures to remain away under the normal strength of the magnet K. The action or operation of the device is, with slight modification, substantially the same as that of the apparatus shown in Fig. 1.

The whole number of lampsLL, or branches containing the same, is such that when circuit isclosed through them all in multiple are there is a combined resistance between the positive and negative supply conductors or mains between which they are placedthat is, a normal resistance-and that will cause a normal derivation of current through the coils of K. The arms or other retractors are so adj usted that under such conditions they will be against their back stops, and the circuits or branches through the resistances It RR will be opened. These branches or resistances, as indicated, are each in multiple arc with the branches of the lampsL L, &e. If, now, a filament of a lamp, L, be ruptured, or the circuit through said lamp be broken by switching or otherwise, the resistance of the multiple-arc group is thereby heightened, so as to increase the difference of potential and to cause more current to flow in the coils of magnet K and strengthen the same. One or more of the armatures A A A are thereby attracted or drawn up, so as to close contact on a plate or stop, D, connected with a resistance, R, thus putting said .resistance into a circuit which is a branch circuit the equivalent of the branch circuit that it supplants. The current in all the branches is thus restored to normal, and the power of the magnet whose armature is drawn up is therefore now the same as it was before the action took place. The armature retains its position, however, because it is now nearer the pole of the magnet and is more strongly acted upon. If two armatures are attracted, one of them will fall away, and so remain until a second lamp is cut oil, and a third action will ensue upon a third lamp being cut off. The fact that one arn'iature i'alls away while the other is retained is due to the circumstance that it is impossible to so construct the magnets that the armatures will move exactly together. The moment one'ol' them begins to move a little ahead of the other the magnet immediately begins to regain its power and will act upon the more sluggish armature, retaining it in position, while the more quickly moving armature will have got beyond the power ofsaid magnet and will drop i'ullyaway. A number of resistances and armatures equal to the lamps L L could be provided; but in practice I iind that with a group of six to eight lamps a smaller number ot'resistances will amply provide .t'or possible extinctions by breakage or accident, it being understood that if all the lamps are to be successively switched an equivalent number of resistances should be provided. The introduction of lamps into the group to replace those that have been exhausted will cause a l'alling away of the armatures successively,on aecountoi" the fall in resistance caused bysuch introduction.

The arrangements that I have described are also useful. in cases where the current on the line a b fluctuates above and below a normal amount. Any increase will, as can be readily seen, tend to increasethe current in the lamps in the group L L, to their injury or destruction, and at the same time will more strongly energize the magnet K, the only result of which, however, is to provoke said magnet to introduce successively resistances R R R in parallel with the lamps to preserve their normal brilliancy and avoid trouble. A decrease of current will act in an opposite way to remove the resistances It and to cause the current to circulate only in the lamps. The arrangement acts, therefore, in part as a regu lator, besides making the compensation which have been before described.

It is evident that the adjustments of the magnet K may be readily varied by loading its armatures, orin any other well-known ways,

to suit lamps requiring a higher or lower potential to operate them, and that, consequently, in a system such as is exhibited in Fig. 2lamps of quite different powers, due to their requiring different electro-motive forces, may be introduced into the same system, since each lamp or group of lamps and its arrangements becomes practically selfregulating on the circuit.

In the switches shown in Figs. 1 and 2 the armature A is made to close a contact at D that will serve to introduce an artificial resistance in multiple arc with a lamp or other translating device. It is sometimes, however, desirable to cause the switching not only to introduce the artifical resistance into a branch, but also to open the circuit to the lamp. Occasion for this extraswitching arises in those instances where the lamp may oll'er too high a resistance without absolutely rupturing the circuit. Such a switching or opening of the circuit to the lamp may be effected by means of a contactsuch as indicated at D, Fig. 5- through which connection from the conductor a is completed to the lamp by simply allowing the switch-lever, or a part connected therewith or with the conductor a, to make contact with the stop D when the armature A is in retracted position, or against its stop S. The closing of the contact at D takes place simultaneously with or a little before the opening of the contact at D, connecting theline to the lamp. In this case it would be evident that the resistance It having been brought into circuit by the attraction of the armature A the introduction of a lamp at L of the proper resistance will not cause the opening of the contact D, since such lamp remains permanently out of circuit, because of the contact D remaining open. In this case, therefore, to re establish the lamp-circuit the armature A must be pulled off, at which time, if the lamp be of normal resistance, the armature A will remain unattracted and the contact D will re main closed.

Vhat I claim as my invention is- 1. The combination,with an electro-magnet, controlling switch-contacts connected to the circuit of said magnet, of a closed conducting band or casing around the core of the magnet, whereby the sensitiveness of the same to quick impulses may be retarded, and whereby also the tendency of the magnet to vibrate the contacts automatically through the changes in the power of the magnet produced by the opening or the closing of the contacts may be lessened.

2. An electric switch-controlling magnet having its armature and retractor therefor adjusted to permit the armature to remain in an attracted or an unattracted position with a normal strength of the magnet, and provided with a retarding band or conductor, B.

3. The combination, with an incandescent lamp or other translating device, of a switch controlling magnet in derived circuit thereto, an artificial resistancein a branch around said lamp controlled by said switch, and a retard IIO ing conducting-band or conductor around the magnet.

4. The combination, with an incandescent lamp or other translating device, of a derivedcircuit magnet and armature therefor adjusted to remain either in attracted or unattracted position when said magnet is normally energized, an artificial resistance,R, in a normallyopen branch around the lamp, a switch controlled by the magnet for throwing said resistance into circuit upon increase of resistance in the lamp branch, and a closed conducting-band, of copper or other material,applied to the magnet for retardingthe action of thoswitchingappliances, as and for the purpose described.

5. The co1nbination,with two or more translating devices, of a derived circuit around the same containing an electro magnet, two or more electric switches operated by said magnet, and resistances controlled by said switches and. placed, respectively, in normally open branch connections around the several translating devices, as and for the purpose described.

6. The comhination,with anelectro-magnet having a multiple core, of armatures for the several individual core portions, and switches controlled by said armatures, as and for the purpose described.

7 The combination of an electro magnet having several core portions and placed in derived circuit to the portion of circuit containmg the work, two or more switches controlled by said electrc-magnet, and artificial resistances, one for each switch, said resistances being in normally-open branches around the portion of circuit containing the working-resistances, as and for the purpose described.

8. The combination, with a group of incandescent lamps or other translating devices arranged in multiple arc, of an electro-magnet in a derived circuit of high resistance around said group, and provided with two or more armatures and artificial resistances in separate normally-open branches around-the group of lamps or other translating devices.

9. The combination, with an incandescent lamp, of two electro-magnetically-controlled switches, a circuit to the lamp governed by one of said switches,and a branch circuit controlled by the other switch and closed simultaneously with the opening of the circuit to the lamp, as and for the purpose described.

10. The combination, with an incandescent electric lamp, of an electro-magnet in a derived circuit thereto, two sets of switch-contacts controlled thereby,'a branch or circuit leading to the lamp and normally closed by one ofsaid sets, and a normally-open branch around the lamp containing an artificial resistance and controlled by the other of said sets.

Signed at Lynn, in the county of Essex and State of Massachusetts, this 27th day of J anuary, A. D. 1886.

ELIHU THOMSON.

\Vitnesses:

M. L. THOMSON, J. \V. GIBBONEY.

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