US835321A - Electric meter. - Google Patents

Description

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IrwOerwtOr am H. Pratt PATBNTED Nov. e, 190e.

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` wim @y W H. PRATT BLBUTR-IC METER. PPLIUATIUN FILED APB. 2o. 1904.

No. 835,321. PATENTED NOV. 6, 196. W. H. PRATT.

ELECTRIC METER.

APPLICATION FILED APE. 20. 1904.

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l/VILLIAM H. PRATT, OF LYNN` MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC METER'.`

Specification of Letters Patent.

Patented Nov. fr, 1906.

To a/ZZ whom it may concern:

Be it known thatI, WILLIAM H. PRATT, a

citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new and useful Im rovements in ElectricMeters, of which the fo owing is a specification.

My invention relates to alternating-current induction-meters; and its object is to provide a wattmeter of "simple and compact construction which shall o crate emciently and accurately on varying oads and power factors.

One feature of my invention consists in the novel arrangement of the magnetic circuit whereby a high torque and roper phase displacement are secured for allloads and power factors.

Another feature of my invention consists in providing means for counterbalancing the starting-frlction, whereby the adjustment for compensating for friction does not alter the phase displacements of the magnetic circuit.

Another feature of my invention consists in a novel connection between the moving y element of the meter and ythe recording mechanism, wherebya displacement of one relative to the other does not introduce errors in the record by changing the friction losses.

Other features of my invention will appear from the following specification and from the' accompanying drawmgs, in which- .Flgure 1 shows a front view in elevation of a meter constructed in accordance with my invention with. the front .cover cut. away.A Fig.' 2 shows a rear view in elevation of theA same with the backof the cover cut away.

.` 2F ig. 3 shows a side elevation of the same 1n cross-section, the lines ,1, 1 and 2 2 in this iig-V ure indicating the planes in which the views of Figs. 1 and 2, respectively, `are 'taken'. Fig. 4 shows dagrammatically the `magnetic circuit ofthe meter and Figs. 5l and show diagr-ammatically't e' relative positions and connections of the coils of the meter.

Referring first to Fig. BVA' represents the front Vcover of the meter, which is-secured to the back cover A by. the bolts a. 'The bolts a are' threaded at both ends, one end screwin'giinto .the studs c of the backbcover A and the other end receiving the nut c". B repre- 'sents the frame, to which all working parts of the meterare attached. Frame Bis bolted.

.by reference to Fig.`4.

the movable armature D, which consists of the usual conducting-disk and the stationary ma netic circuit, with its energizing-coils. Dis D is carried by shaft c, which 1s supported in the usual manner on 'eWeLbeaTings carried by the frame B. T e 'stationary magnetic circuit consists of-two laminated cores C and C', secured to frame B by the bolts c. The arrangement of the magnetic circuit and its coils will best be understood In this figure core C is shown with three aralel members connected at the top wit the potential-coil P, mounted on the central member. has its extremities extending intoclose roximit with the` three members orV o lcs oFcore C,A t ereby forming withcore` a nearl 'closed magnetic circuitfor potential-coil .whereby current in coil P 1s lagged 'in the4 manner well understood in the art'.` Oore C is provided with two poles facing the central e of core C. On these poles are placed the series or current coils S.1 V ,A

The disk, which isnot shown in Fig. 4, is disposed between thepoles on which coils S are placed and the centrall pole of core .C. The' leakage flux of'coilP, which does not ass through the nearly-closedcircuit offered Core VC by the extremities of core C', passes fromthe central pole of core'C through the-diskfc0 the oles on' '.which are mounted thecoils S." he coilsS S are oppositely Wound and profduce fluxes which with thei'u'x from the central pole f core C produce a shiftingesultant ixj'and consequent rotation'of the disk, in aj manner well understood inV the; art. i The short-circuitedcoil L is mounted oir-theniids .dle pole .of coreC andis traversed-bythe ffiux that passesthrough the .diskto theSpoles-ef the .series coils',- andfthereby produesthe nir'ietiy-degree displacement yof the potential.-

flux om that ofthe series coils in the'nlannerunderstoodlin theart.; 'Y

It will b'e eeen from the drawings the above'description that fthefs'eries coils Q have e nearly-closed magnetic circuit und acup to the terminal cordingly exert e strong torque. The errangement of the cores (l and C is compact and well adapted tor producing the proper phase displacement ot the fluxes.

In order to com icnsute for the sluiting friction, I rovide the closed circuit it, which is suspenc ed directly above the disk und which may be moved ho'rizoiiititlly townrii either series coil. When this closed circuit is in its central position, syn'nnetrically disosed with reference to the uiugzjnctic circuit of the shunt-coil, it luis no elli-.ct upon the starting torque of the` meter. ll it is univr-.d in either direction from its ccntrui position se thatO it is assynnuetricclly disposed with rei! ererce to'the seid magnetic circuit` torque is pro uced thereby in one direction or the other, sind the st m'lingd'rictioii is thereby compensated for. Moreover, since there ure two series coils and sincr` the closed circuit E by its movement incliulcf. nuire ol' the fluir from one coil es it includes less inn; tbc other, the bese displacement ci' tur luxrs is not altere( by its adjustment. iConseouenlly I have rovided e simple means for compete; eating or sturtinghfriction withoutwei-ying the phcse displacement, und ti'lcreby im'uuir-4 ing the accuracy of the meter. The cllosed circuit E, which is formed :is e. simple rec-- tangular loo i, es shown in Fig. 5,` is sup-v ported from ironie B by the clumpingscrews e, as shown in Figs. 1 and 3. The clernpingscrews c ass thrruigb slots in lugs on the end of plete as shown in Figs. i and P, and permit the member E to be moved horizontally by Ineens of the lever F, which is pivotcd :rtf and engages one of the upturned lugs of member c'.

The drg-megnets M ere shown in Figs. l and 8 and are supported from frame B, es in diceted in the drawings. The dial-plete H is supported on studs h, carried by freine B, es shown in Fig. 3. The connection between the disk D und the mechanism for the die]u plate is as follows: Shaft d carries e., worm t, which en ages u geur-wheel mounted on shaft y', w ich is supported from traine B 1n close roximity to the upper support of shaft The maintenance of perfect elinement between Worm 'i and shaft is thereby assured. Shaft carries an arm k, which es it revolves engages s pin m, carried by shaft n, Which is connected to the gear-trein. (Not shown.) Arm 7c drives pin 1ny by simply pressing against it, thereby forming e loose yet positive connection between. shaft j and shaft fn. Any displacement of the dial H with its geentrain relative to disk-shaft d can produceA no binding in any part of the transmitting mechanism, und consequently can introduce no frietional error.

Fig. 5 shows diegrammetieelly the errangement of the coils and their connections. The lagging coil L has its terminals brought l l l i l ill i l l l l l ilutc l in order that its elfcct muy be vitrier by thc insertion of rcsistuncc in its circuit, if required. Fig. 6 shows u modified arrangement in which two sets of series colis crc used. Such :tu m*- rungcment is suited l'or measurement of cncrgy on u three-Wire system. No further explanation is believed nm'cssury.

Vhiie lV have shown n complete embodiment of my invention, it will be understood that the construction und arrangement of parte` muy be greatly clnmgcd without departing from the spirit of my invention. li`iirthermmc, l have shown und described severe! novel. tentures which. l desire to claim whether' used together or singly.

Acciirdingly i do not desire to limit myself to the purticuler constructibn. end arrangement of purts here shown, since changes 'which do not deport from the spirit'of my in vention und which crc `within the scope of the nl peiided claims will be obvious to those skilled in the crt What i cluim ns new, und desire to secure by Letters Patent of the United States, is

1. ln an electric meter, a magnetic core comprising three parallel members joined et one end, e potentiel-coil mounted on the centrel member thereof, e rotatable disk mounted. opposite seid central member,l e second core extending into close proximity` to said members and forming therewith a neerl closed magnetic circuit for seid potentialcoil independent of seid disk, end a series winding arranged. opposite sari d central member on the other side of seid disk.

2. In an electric meter, e magnetic core comprisingr three parallel members joined et one end, the central member extending beyond the other two, a. potential-coil `mounted on seid central member, a, second core eX- tending into close proximity to said members end forming therewith a nearly-closed ma netic circuit tor seid potentiakcoil, a closedcircuited coil. .mounted on the extension'of said. central member, e series Winding disosed o )positie the end of said central member, en( a rotatable disk mounted between said central member and seid series winding.

3. In en electric meter, e magnetic core comprising three parallel members joined'at one end, u potential-'coil mounted on the centrol member thereof, a rotatable disk mounted opposite said central member, a, second core extending into close proximity to said members and forming therewith' a nearlyclosed magnetic circuit `for seid potentialcoil independent of said disk, an e series windingmounted on said second core opposite seid central member.

4. In en electric meter, s` magnetic core comprising three parallel members joined at one end, the central member extending beyond the other two, a potentiateoilmouuted on said central member, a. secondcore ex- XCC tending into close proximity to said members and forming therewith a nearly-closed mag netic circuit for said potential-coil, a closedcircuited. coil mounted on the extension ol said central member, a series winding mounted on said second core opposite said. central member, and a rotatable disk mounted be tween said central member and said series winding.

5. In an electric meter, a magnetic core comprising three parallel members joined at one end, a potential-coil mounted on the cenH tral member thereof, a rotatable disk mounted opposite said central member, a second core extending into close proximity to said members and forming therewith a nearlyclosed magnetic circuit for said potential-coil independent of said disk and having two olar rejections opposite to the central memlier o the first core, and series coils mounted on said polar rejections.

6. In an e ectric meter, a magnetic core comprising three parallel members joined at one end, the central member being longer than the other two, a potential-coil mounted on said central member, a second core extending into close proximity to said members and forming therewith a nearly-closed magnetic circuit for said potential-coil and havin two polar projections opV ositeto said centra member, and series coi s mounted on said polar extensions.

7. In an electric meter, a magnetic core comprising three parallel members joined at one end, the central member rextending beyond the other two, a' potential-'coil mounted on said central member, a second core' extending into close proximity to said members and forming therewith a nearly-closed magnetic circuit for said potential-coil and having two polar projections o posite to said central member, series lcoi s mounted on said polar projections, and a' closed-circuited coil mounted on the extension of said central member.

S. In an electric meter, a magnetic core having polar projections, a potentialcoil mounted thereon, a rotatable disk opposite said polar projections, a second core extending into close proximity to the first core and forming therewith a nearly-closed magnetic circuit for said potential-coil independent of said disk and having polar projections o posite to a pole on the first core energize by said potential-coil, and series coils mounted on sald last-mentioned polar projections.

9. In an electric meter, a magnetic core, a potential-coil mounted thereon, a second core extending into close'proximity to the first core and forming therewith a nearly-closed dispose between said. two poles and the first-named pole and adjustable relatively thereto.

11. In an electric meter, a potential-coil, a pole energlzed thereby, two serles coils, two poles energized thereby and facimy the hrstnamed pole, and a short-circuitei conduct-- ing member disposed between said two poles and the Alirst-named pole and adjustable in a plane per endicular to the llux passing between sai poles.

12.v In an electric meter, a potential-coil, a pole energized thereby, two series coils, two poles energized thereby and facing the firstA named pole, and a short-circuitcd conducting member embracing'a portion-of the flux 'from each series pole and ad'ustable to vary simultaneously andoppositely the portion of the iiux from each series pole embracedy thereb i.

13. In an electric meter, a poteiitial-coih a pole energized thereby, two series coils, two poles ener ized thereby and facin the {irstL named po e, and a short-circuiter conductingmember embracing a portion of the linx from each series pole and adjustable toward either series pole in a plane perpendicular to the flux.

14. In an electric meter, a rotatable disk,

magnetic poles on opposite sides of said disk, a short-cnculted conducting member disposed between said poles andadjustablein a plane parallel to the plane of the disk, and a ivoted adjusting-lever engaging said memer.

15. In an electric meter, a rotatable disk, :magnetic poles on opposite sides of said disk, a s posed between said poles and adjustable in a plane parallel to the plane of the disk, and4 a pivotedadjusting-lever engaging said memer and movable in a plane perpendicular to the disk.

In witnesswhereof I have hereunto set my hand this 18th day of April,1904.

WILLIAM H.l PRATT.

Witnesses: l

DUGALD Meli. MoKILLor, HENRY O. Wns'rnNDAnr.

ort-c1rcuited conducting member dis-Y TOO IOC

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