US326894A - James j - Google Patents

Description

2 Sheets-Sheet 1,

(No Model.)

J. J. WOOD.

GURRENT REGULATOR FOR DYNAMO ELECTRIC MAGHINES.

Patented Sept. 22

(No Model.) 2 Sheets-Sheet 2. J. J. WOOD.

CURRENT REGULATOR FOR DYNAMC ELECTRIC MACHINES.

N0. 326,894. Patented Sept. 22, 1885.

\ lllllllll W/ T/VESSES N. PETERS, Fholu-Ulhographer. Wasbingiom 0.6

UNiTED STATES PATENT GEEicE.

JAMES J. lVOOD, OF BROOKLYN, ASSIGNOR TO THE FULLER ELECTRICAL COMPANY, OF NEW YORK, N. Y.

CURRENT-EEGULATOR FOR DYNAMO-ELECTRIC WIACHHJES.

SPECIFICATION forming part of Letters Patent No. 326,894, dated September 22, 1885.

Application filed March 6, 1984. (No model.)

To all whom it may concern:

'Be it known that I, JAMES J. W001), of Brooklyn, Kings county, New York, assignor to the Fuller Electrical Company, of New York city, New York, have invented certain new and useful Improvements in Current- Regulators for Dynamo-Electric Generators, of which the following is a specification.

My invention belongs to that class of regulators in which the strength of current is antomatically varied or regulated to correspond with changes in the workingcircuit by shitting the brushes on the commutator more or less between their maximum and minimum positions, so as to keep the current constant in the circuit, or nearly so. In this regulator I employ an electro-magnet in the working circuit, arranged to impart mechanical power from the revolving armature-shaft of the ma.- chine to the brush-holder, to shift the brushes more or less between the minimum and maximum points, according as the condition of the circuit requires; and inyinvcntion consistsin the particular mechanical and electrical mechanism employed for this purpose, as hereinafter fully set forth, whereby a very sensitive regulator, simple in its construction and effective in action, is obtained.

In the drawings annexed, Figure 1 presents an end elevation of a- \Vood-Gramme dynamo electric machine provided with my improved regulator, and Fig. 2 is a fragmentary side elevation of the same. Fig. 3 is a fragmentary cross-section inside the frame, between the brush-holder and the commutator, showing the brush-holder and its engaging operatingpinion. l is a fragmentary sectional plan showing the end of the armature-shaft and the shifting frictional or clutch wheel, whereby motion is imparted from the shaft to the brush-holder. Fig. 5 is a diagram illustrating the circuit of the apparatus and the action of the electrical parts of the regulator. Figs. 6 and 7 illustrate modifications of the clutching devices. Figs. 8 and 9 illustratein detail the stop device of the regulating mechanism.

In the drawings, a indicates the frame of the machine, 6 b the field-magnets, and c the armature, which revolves between the poles of the field-n1agnets in the usual manner.

(Z is the commutator, and c the armatureshat't, the ends of which revolve in bearings on the middle of the end frames, a, in the ordinary way. One end of the armature-shaft is fitted with a driving-pulley, as usual, this end not being shown in the drawings, while the opposite end projects freely from the bearing on the outside of the frame a, as shown in Figs. 1 and 2, and the extremity of this end of the shaft is reduced slightly and turned to serve as a friction-roller, f, which projects into a deep groove in a frictioirwheel, q,which is mounted on the outside of the frame over the projecting end of the armatureshaft, as shown well in Figs. 1 and 2 and in section in Fig. 4. This friction wheel g is hung on a stud 011 the short arm of an elbow-lever, h, which is pivoted on the outs de of the frame a, and the long arm of said lever is connected by links h to the armature of a strong electromagnet, i, preferably of solenoid form, which is fixed on the outside of the framea, near the upper corner thereof, as shown best in Figs. 1 and 2. This lever his connected to astrong retracting-spring, k, which is provided with suit-able means of adjustment, as shown, and which opposes the attraction of the magnet '13. The lever is also connected with the piston of a dash-pot, j, as shown, to prevent too quick or jerky movements of the lever, and its end moves between stops Z Z, whereby the motion is limited, as will be understood; but said stops or dash-pot are not essential.

Now, in in (see Figs. 2 and 3) indicate the brushes, which rest on the commutator and collect the current therefrom, and which are supported from each end of the adjustable yoke or brush-holder a, which is free to turn on the neck of the bearing of the armatureshaft just within the frame a in the usual manner, as will be understood from Figs. 4 and 3. The periphery of the yoke for a part of its circumference is toothed, as shown, forming a segment of a gearwheel, including about one-third or more of a circle, as shown in Fig. 3, and into this segment a small pinion, 0, meshes, as shown well in Figs. 2 and 3, which pinion is "fixed on the inner end of a small shaft, 0, which passes through a bearing in the frame a, and on the outer end of which shaft is fixed a gear-wheel, p.

Now, the hub of the friction-wheel g, as shown best in Fig. 1, is toothed to form a pinion, 9, which meshes with an intermediate gear-wheel, r, mounted on a stud on the out side of the frame a, adjacent to the gear-wheel p, which intermediate wheel has a pinion, r, on its hub, which meshes with the said gearwheel 1), as shown by full and dotted lines in Figs. 1 and 2. It will therefore be seen that the friction-wheel gis operatively geared with the brush-holder through the train of gearing g r 9" 0, so that if thei'riction-whecl is revolved rapidly in one direction or the other the brush-holder will be shifted back or forth, and the brushes thus correspondingly shifted on the commutator into any desired position between minimum and maximum. Now, it is of course well known that in machines of the Gramme type and others, when the brushes rest on the commutators at certain points, known as the maximum points, the full or maximum current of the machine will be conducted off, and if the brushes are shifted to a position at nearly right angles to the maximum position the current will be ml, the practical minimum position being, however, about sixty degrees from the maximum, so that hence the current may be varied to any desired degree between minimum and maximum by adjusting the position of the brushes between said points. Now, the brushes are thus adjusted automatically to keep the current regular or at a normal standard notwithstanding changes in the circuit, such as increase or decrease of lights in action, by means of power transmitted from the armatureshaft to the friction-wheelq, controlled by a magnet in the working-circuit, as will now more clearly appear.

Referring therefore to Figs. 1, 2, and @t, it will be understood that when the machine is in opeiation, supplying, say, an electric arelight circuit, the armature will of course be revolving rapidlysay about one thousand revolutions per minuteand the end f of the armature-shaft (see Figs. 3, 2, and 1) will hence be revolving rapidly within the grooved rim of the friction-wheel g, which groove is a little wider than the diameter of the rollerf, so that while the roller remains in a mid-pd sition in the groove it will touch neither side, and hence no motion will be imparted to the friction wheel. If, however, the wheel is swayed slightly one way or the other, so as to press either side of the groove against the periphery of the roller, the wheel will be frictionally clutched to the revolving armatureshaft, and hence rotary motion will be imparted directly from the power-driven armature-shaft to the wheel 9 and its connected train of gearing, so as to positively shift the brushes one way or the other on the commutator, thus raising or lowering the force of the current according to the direction in which the wheel is swayed, as will be readily comprehended. Now, this swaying 1' clutching motion of the friction wheel is one side of the revolving roller f.

effected by the motion of the elbow-lever h, controlled by the attraction of the magnet 1' and the retraction of the spring 70, according as the current rises or falls in strength so as to vary from a certain normal standard. This magnet i is situated in the working-circuit, as indicated in diagram in Fig. 5, and hence it the working-current varies in strength by an increase or decrease in the number of lights the attraction of said magnet will vary correspondingly. Now, whatever may be the number of lights in action, from the minimum up to the maximum number which the machine is capable of supporting, the strength of current should be up to a certain standard, so as to keep a galvanomctor-needle deflected to a certain degree, and to furnish such current the commutator-brushes will of course be adjusted to some definite position between their minimum and maximum positions. \Vhen, therefore, the current is at this normal standard, the attraction of the magnet 1' will just balance the retraction of the spring 7., and the lever It will remaiii in a mid-position between its stops, and the grooved rim of the friction-wheel y will also be in a mid-position over the roller f, and hence out of contact therewith, so that the brush-shifting mechanism will remain at rest, and the brushes will,remain in whatever position they may be already set. Now, while nothing occurs in the action of the lamps, or otherwise. to alter the current from its normal standard or appreciably vary the deflection of the galvanometer,the brushes and the entire regulating mechanism will remain in the position of repose already indicated. If, however, one or more lamps should be come switched out of action, either voluntarily or automatically by their safety or automatic cut-out devices, then the current would become suddenly strengthened relatively to the reduced resistance then in circuit, so as to suddenly increase the deflection of the galvanometer, and therefore increase the attraction of the magnet i, causing it to overcome the spring k, and thus sway the lever hand wheel 9 in a direction to bring the inner and smaller friction-rim of the grooved wheel 9 against This will immediately cause the wheel 1 and its connected train of gearing to revolve backward, and thus shift the brushes toward the minimum position, so as to reduce the current strength toward the normal standard, and when the brushes are thus brought to the proper position, so as to reduce the current to the normal standard, the attraction of the magnet 2' will then of course again equal the retraction of the spring is, and the pressure of the rim of the wheel against the drivingroller will be relaxed, and the wheel thrown out of contact into its mid-position, as before, thus leaving the brushes at the correct position to keep the current at standard strength suited to the altered condition of the circuit. If, on the other hand, an additional number of course the current would be proportionately weakened, and the retraction of the spring It would overcome the magnet z, and therefore sway thelever and wheel h g in the opposite direetion, and cause the outer and larger side of the grooved rim to contact with the opposite side of the roller f, thereby causing the wheel and its connected train of gearing to revolve forward, and thereby shift the brushes toward the maximum position, so as to increase the current. As soon, however, as the brushes have been advanced sufficiently far to raise the current to the standard strength,the magnet i and spring It will become balanced, as before, and the friction-wheel brought out ofcontact with the drivingroller at its mid-position,

as before, leaving the brushes at the correct adjustment, as will be readily comprehended. In order, however, to prevent the possibility of the brushes being moved beyond the maxi mum position by any residual momentum of the wheel 9 and its train of gearing or by any tardy action of the magnet i or spring k, the final wheel p is provided with a cam, pin, or projection, s, and the lever h with a corresponding cam, lug, or projection, s, as best shown in Figs. 8 and 9, also by dotted lines in Fig. 1, so arranged that as the brushes approaeh the maximum position the said pin .9 will ride under the projection s, and thus positively raise the lever and throw the friction-wheel out of contact with the driving roller f, so that it is thus impossible for the brushes ever topass the maximum position.

It will be therefore seen that any change in the circuit will be at once felt by the regulater, and an adjustment of the brushesimmediately made to remedy it, and it will be readily seen that the mechanism described will make this adjustment so promptly and rapidly that the change in the circuit, however quickly it may happen, will cause but a momentary wave in the current, so that the galvanometerneedle would be deflected but for a short interval beyond its normal degree, and immediately brought back again to the said degree.

It will be further noted on referring to Figs. 1 and 4, that when the brushes are being shifted toward the minimum point to reduce the current, the friction-roller f acts on theinner edge of the grooved rim of the friction-wheel g, which is of the smaller diameter, whereas when the brushes are being shifted toward the maximum the friction-roller will act on the outer rim of larger diameter; hence by this arrangement the adjustment to increase the current is made in a slower manner than the adjustment to reduce the current, for the reason that a fall in the strength of current can do no injury to the circuit, whereas a sudden or great rise in strength might be injurious if not at once checked, and therefore it is desirable to reduce any increase as rapidly as possible, which is accomplished by the arrangement shown.

I have assumed thus far that the magnet 6 alone controls the action of the regulator, in which case a slight change in the working circuit would make but a slight change in the attraction of the magnet, whereas it is more desirable that a slight change in the workingcireuit should cause a great change in the at traction of the magnet i, so that this magnet will act with. greater sensitiveness and power, and thus cause the regulating mechanism to act with much greater energy and promptness. I hence prefer to use an additional magnet in the working-circuit, the variations of which will act through a contact device to shunt more or less current through or around the magnet i, and thus accomplish the purpose above named. This additional magnet and contact devicel have not, however, shown in Figs. 1 and 2, for sake of greater clearness, and also because the magnet i alone will suffice for practical operation; but I prefer in most all cases to use the said additional devices in connection with the magnet 13, and have illustrated the same fully in Fig. 5, which shows the complete electrical features of the apparatus in diagram. Referring therefore to Fig. 5, i indicates the additional or shunting magnet, which is placed in the working-circuit with the magnet i. The armature of the shunting-magnet however, connected to the contact-lever 1 one arm of which presses upon and controls a variable contact device, a, which I prefer to form of series of superposed earbon plates, thereby forming a relaxing contact or variable conductor, which is preferable to a separating contact, although the latter .may be used, if desired. The conductivity of this contact device a will of course greatly vary according as the plates are pressed firmly together or relaxed without at any time separating the plates, and hence this form of contact is much preferable for the present purposeemploying powerful currentsas it affords a large surface of poorly Conducting material and avoids actual separation, (except under extreme changes,) which would cause too sudden change in the strength of the magnet '27, or sparking or jumping of the current.

Now, the contact device a is included in a shunt, o o, from the working-circuit, which also includes the nmgnet 73, but does not include the magnet 15, which is in the workingcireuit only, as shown, and the attraction of the magnet tends to move the lever y, so asto relax the plates of the contact a, and thus greatly decrease the con( luetingpower of the shunt o y a, whereas the retracting-power of the retraetings n'ing w tends to compress said plates, and thus greatly increase the conductivity of the shunt. It will therefore follow that any decrease of strength in the working-circuit will weaken. the magnet 17, as before described, and also correspondingly weaken the magnet t. 'lhis weakening of the magnet It will, however, cause its retracting-spring w to preponderate and retract the lever 3 and ITS thus compress the plates of the contact it, thus greatly increasing the conductivity of the shunt c ya, or reducing its resistance relatively to the resistance of the magnet 'i, and thereby cause a greater portion to the current to be shunted or directed away from the magnet i, as shown by dotted arrows, thus greatly weakening the magnet t', and therefore causing it to act with great energy and promptness on the regulating mechanism in the manner before described. If, on the other hand, the current should become abnormally strengthened in the working-circuit, the action of the parts would of course be reversed, the magnet 'l; attracting the lever y, and thus rclaxing the contact a, and thus greatly increas ing the resistance of the shunt relatively to the resistance of the magnet i, and thereby causing a greater portion of the current to flow through the magnet 2', thus greatly strengthening it in comparison to the small change of strength in the magnet 15 and in the working-circuit. It is hence obvious that by this means the magnet 13 is rendered very sensitive and energetic in response to small changes in the working-circuit, and will therefore act on the regulating mechanism so as to restore the circuit to its normal condition always with great celerity, no matter how slight the changes may be, which is very desirable in large elec tric circuits, particularly for are lighting.

It will of course be understood that both magnets ia-nd t are wound with large wire, as both are situated in the working-circuit, as illustrated.

In order to indicate on the regulator the number of lamps, motors, or other electric consuming or transmitting devices which may be in action at any one time, one of the wheels of the regulatorprelcrably the final wheel, p-is graduated around its periphery, as shown in Fig. 1, with graduations representing successive numbers of lamps or their equivalents, and a pointer, m, affixed to the frame a of the machine, overhangs the graduated rim and acts as afixed index-finger to said graduations. These graduations are of course so disposed that when the wheel is revolved into positions to place the brushes at adjustments corresponding to certain numbers of lights, the graduation corresponding to said number of lights will be in register with the pointer 50, as will be readily understood, thus forming a simple gage, which will enable the engineer, by a glance at the regulator of the machine, to know how many lamps are in action at any time, which for many reasons is often desirable, as will be appreciated.

It is of course not essential that the driving-rollerf be directly on the end ofthe armature-shaft, as intermediate gearing or connections might intervene between the same and the armature-shaft; or the roller f might be revolved by power independent of the armature-shaft; but of course the direct construction shown is preferable.

I do not confine myself to the lever h for shifting the clutch-wheel g, and the gearing shown for operatively connecting the wheel with the brush-holder. The essential feature of this mechanical portion of my regulator consists in the clutch wheel or disk g, grooved, or its equivalent, on its side, with the drivingrollerf, acting on either side of the groove by a shifting motion radial to the grooved wheel, which, as will be readily appreciated, is a very simple and efiicient arrangement. In this device I prefer, of course, to have the roller f non-shiftable and the wheel 9 shiftable, as described; but this relation might of course be reversed, if desired.

Where the contact-magnet t and the shunt and contact device a c y are not used, the magnet i might be substituted by the field.- magnets of the machine itself, the armature connected with the lever it being arranged in relation with the poles of the field-magnets so that any variation in the attraction of the magnets due to any variation in the current would operate the lever h with the same effect as in the case of the distinct magnet Again, where the magnet t is used as a distinct magnet and the contact-n'iagnet i, &c., used with it, then the fieldmagnets may serve as the contact-magnet t, the armature connected to the contact-lever y being simply arranged in relation to the poles of the field-magnets as shown by dotted lines in Fig. 5, and the same effect will be produced as though the contactmagnet was distinct from the field-magnet. In fact I prefer said arrangement to the employment of a distinct contact-making magnet.

Instead of having the wheel 9 with a groove and one roller, f, to fit therein, the wheel may have a projecting rim in place of the groove fitting between two rollers, ff, as shown in Fig. 6, one of the rollers, being on the end of the armature shaft, as before, and the other roller, f, geared to the shaft so as to revolve reversely, as shown; hence when the wheel g is shifted it will engage with one roller or the other, and hence be revolved backward or forward with the same effect as before. This I regard as a simple equivalent or reversal of the preferred construction, as in both forms the wheel 9 has two frictional surfaces at different radial distances on the side between center and circumference to engage with one or more drivingrollers in opposite directions. The engaging surfaces of the friction-rim and the rollers might of course be toothed or roughened, but a smooth surfaceis preferable.

I have described the rollerf as acting on two friction-rims of different diameters, so as to revolve the brushes backward quickly and forward slowly. \Vhen, however, it is desired to have the brushes move in "both directions at uniform speed, the roller and rim may be formed with a stepped profile, as shown in Fig. 7, so as to produce a uniform rate of rotation in both directions.

I am aware of the patents issued to Maxim, No. 228,5at3, and to Thomson at Houston, Nos.

223,659 and 238,315, and claim nothing therein shown. In the Thomson &.Houston patents the power of the magnet and its retracting device is directly applied to shift the brushes. In the Maxim patent, however, the magnet acts to clutch a power-driven device to the shifting mechanism to shift the brushes by mechanical power; but in this case the clutching-magnet is not in the working-circuit itself, but in distinct or charging circuit, and is controlled by a separate magnet in a shunt of the working-circuit.

Vhat I claim as my invention is as follows:-

1. The combination, in a dynamo-electric machine, with adjustable commutator-brushes and mechanism arranged to shift the said brushes between their minimum and maximum positions, and with a power-driven device adapted to be clutched to said shifting mechanism in either of two directions, to revolve the brushes backward or forward, of an electro magnet having its coils arranged directly in the working-circuit of the machine with its armature operatively connected with the clutching device, and a retracting device opposing the said magnet, whereby variations in the working-circuit directly affect the attraction of the said magnet and cause a direct adjustment of the commutator-brushes, substantially as herein shown and described.

2. In a current regulator for electric gencraters, the combination, with adjustable commutator brushes, mechanism for shifting the same and a power driven device adapted to be clutched to said mechanism in either direction, to revolve the brushes forward or backward, of two magnets, both arranged in the workingcircuit of the machine, one of the magnets and its retracting device controlling the clutching of the power-driven device to the shifting mechanism, while the other magnet controls a cont-act which varies or shunts the first magnet, substantially as and for the purpose set forth.

3. In a current-regulator for electric gener ators, the combination, with adjustable com mutator-brushes, mechanism for shifting the same, and a power-driven device adapted to be clutched to said mechanism in either direction, to revolve the brushes forward or backward, of the magnet 2', arranged in the working-circuit and controlling the clutching of the power device to the shifting mechanism, with the magnet i, also arranged in the working-circuit,

a shunt, o, in the working-circuit around said magnet t, and a relaxing-contact, a, in said shunt controlled by the magnet 25, substantially as and for the purpose set forth.

4. In an electric generator, in combination with adjustable commutatorbrushes, the reversible clutch-wheel g, geared with the commntator-brushes and having two frictional surfaces at different radial distances on the side between center and circumference, with a rotary driving roller or rollers arrangedin re lation thereto, and. an electric-motor device for throwing the roller or rollers into engagement with either side of the rim, substantially as and for the purpose set forth.

5. In an electric generator, the combination, with adjustable commutator-brushes, of the reversible clutch-wheel g, having a groove on the side between center and circumference, with adriving-roller, f, fitting loosely therein, and an electric-motor device for engaging either side of the groove with said roller, sub stantially as and for the purpose set forth.

6. In an electric generator, the combination, with the adjustable commutator-brushes, and with the revolving armature-shaft, of the driving-rollerf on the end of said shaft, with the clutch-wheel g, geared to the brush-holder and having a grooved side to overlap and engage said roller f, and with an electro-magnet device arranged to clutch the said wheel and roller in opposite directions, and thereby shift the brushes to and fro, substantially as set forth.

7. In a current-regulator for electric generators of the class described, the combination, with the movable brush-holder, of a reversible clutch -wheel geared therewith having two frictional surfaces at different radial distances from the center of the wheel, with a rotary driving roller or rollers arranged to engage either face, and an electric-motor device for automatically causing said engagement by variations in the current and so arranged that the roller engages the inner rim of smaller diameter to shift the brushes back to reduce the current, but engages the outer rim of larger diameter to shift the brushes forward to increase the current, substantially as set forth.

8. In a current-regulator of the class shown, the combination of the movable brush-holder and a train of wheels geared therewith and adapted to receive power to revolve said train one way or the other, one of said wheels being graduated to represent successive positions of the brushes corresponding to successive numbers of lamps or their equivalent in circuit of an index-point arranged in relation with said graduations, substantially as herein set forth.

9. The combination, in an electric generator with adjustable commntator-brushes, of the movable clutch-wheel g, a train of gearing between the brush-holder and clutch-wheel, the initial pinion of which is movable tangentially or like a planet-wheel in the teeth of the succeeding wheel, with the clutching-lever h on which said wheel is hung, a powerdriven roller arranged to engage the wheel in opposite directions, and an eleetro-magnet, i, and retracting-spring k, connected with said lever and arranged to shift it in one direction or the other, substantially as and for the purpose set forth.

10. The combination, in an electric generator with adjustable commutator brushes, shifting mechanism geared with the said brushes, a powendriven device for revolving Ward the maximum, and thereby automatically said shifting mechanism, and means, substan' unelutch the power-driven device from the i0 tiallysueh asset forth, for clutching thepowershifting mechanism, substantially as and for driven device to the shifting mechanism to the purpose set forth.

5 revolve it one way or the other, of an engaging- JAMES J. \VOOD.

stop device on some part of the shifting rnechlVitnesses: anism, so arranged as to engage the clutching (Jrms. M. HIGGINs, mechanism when the brushes are shifted to- Jim. E. GAVIN.

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