US972538A

US972538A - Maximum-demand meter.

Info

Publication number: US972538A
Application number: US40147407A
Authority: US
Inventors: Vladimir Karapetoff
Original assignee: Individual
Current assignee: Individual
Priority date: 1907-11-09
Filing date: 1907-11-09
Publication date: 1910-10-11
Anticipated expiration: 1927-10-11

Description

- V KABAPETOFF,

MAXIMUM DEMAND METER.

APPLICATION FILED NOV. 9, 1901.

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CONTACT ELDER v. KARAPETOPP. MAXIMUM DEMAND METER. XPPLIOATION FILED N0V.9,1907.

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V. KARAPBTOFPE MAXIMUM DEMAND METEE. APPLICATION FILED NOV. 9, 1 907.

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UNITED STATES PATENT .QFFFGE. I

VLADIMIR KARAPETOFF, OF ITHACA, NEW YORK.

MAXIMUM-DEMAND METER To all whom t t-may concern:

Be it knownthat I, VLADIMIR KAnAPnworn, a subject of the Emperor of Russia, Y residing at Ithaca, in the county of Tompkins and State of New York, have invented certain new and useful Improvements in Maximum-Demand Meters, of which thefollowing is a specification, reference being had to the accompanying drawings.

My invention relates to improvements in electric meters commonly known'as maximum-demand meters.

An object of my invention is to provide a meter of the class described which will have a wide range of adaptability to the varying conditions ofuse to which it may be put.

One feature of my invention is the provision of electromagnetic means for the releaseof the pointed-positioning device from the wattmeter and the restoration of the former, together with the maximum-indieating pointer, to its initial position. The electromagnetic device which releases and resets the pointer-positioning device is separate from the electromagnetic device which resets the maximum-indicating pointer.

Another feature of my invention lies in the provision of means for adding the periodic maximum displacements of the maximum-indicating pointer;.that is, the maxi mum displacements in a period of, say,-

twenty-four hours is added to the maximum displacement'occnrring in the next twentyfour hour period and so on, whereby at the end of the longer period, for which the bills are made out, the. latter may be based upon the monthly sum of these displacements (or maximum power -deinands) or upon this sum divided by the number of days in the month. I A third feature of my invention resides in the provision of means for imposing upon the consumer a penalty for using power in excess of :the stipulated maximum. This may be done by giving to the pointer a displacement equal to the product of a multi plier and the displacement of the pointerpositioning device during that part of' the travel of the device which occurs during a use by the consumer of power in excess of the stipulated amount. Means are also provided to carry out terms which appear in;

some agreements stipulating that the allowable maximum shall vary with the hour of the day and-with the day of the week.

A further feature of my invention con- Specification of Letters Patent. i Patented O t 11 1910; Application filed November 9, 1907. Serial 110401374.

sists in the provision for adding the periodic excess power-demands over the allowable maximum power-demand stipulated by the agreement; that is, instead of adding the periodic maximum displacements, only the periodic excesses of these maximum displacements over the allowable maximum are added. In case the excess exceeds an allowable amount, a penalty may be imposed, as hereinbefore stated. 4

Other features of my invention will be set forth in the d scription which follows hereinafter.

In the drawings illustrating the principle of my invention and-the best mode now known to me of applying that principle, Figure 1 is an elevation, partly in section, of my new maximum-demand meter of which some of the parts are shown conventionally; Fig. 1 is a View entirely similar to Fig. l but showing a modified form in which mechanism is provided moving the guard-plate;

Fig. 2 is a detail of the delayed-action makeand-break device; Fig. 3 is a detail showing amodification of the make-and-break device of Fig. 2; Figs. 4c and 5 are details showing the electromagnetic device for restoring the push-arm or positioner toits initial position;

- Fig. -6 is a detail of a modified form of the mechanism for restoring the push-arm to its initial position; Fig. 7 1s a plan view of the dial; Fig. 8 is a section on the line AA f of Fig. l Fig. 9 is a section on the line BB of Fig. 1; Fig. 10 is a detail in plan of the -manuallyadjustable guard-plate used in the apparatus shown in Fig. 1; and Fig. 11 is a detail of a modified form of a device for moving the guard-plate.

The integrating wattmeter a is connected with and drives my new meter through its shaft 2) provided with a pinion c which meshes with a toothed wheel or gear (Z. Upon the same shaft with the latter is a pinion c which drives a toothed wheel 7 fast upon the driving shaft 9 of my new meter. The last-named shaft carries the lower member h of a friction-clutch the upper member 2' of which is provided at its top with an armature the peculiar form or shape of which is best shown in Figs. a and The armature lies between polepieces 7c which are momentarily energized from time to time, (say, at one-minute intervals) by a current made to flow through the coil in. An L-shaped positioner or push-arm n is carried by the armature j on the lower end ins ' closely resembles in shape the armature j,

which is mounted the aforesaid upper member 2' of the friction-clutch; and the free upper end of the arm n is adapted to engage and push against the horizontal part p ofa maximum-demand indicator or pointerq. The latterx-isi mounted upon the shaft 7 which carries also an armature s which he'reinbefore referred to. The armature s *1 lies between the pole-pieces t which are energized momentarily from time to time (say, at intervals of twenty-four hours) by a 5.;urrent made to flow through the coil u. The index end 'v of the pointer 9 travels over put in circuit with the coil m; or the devices shown in Fig. 6 may be used. Where a contact-clock (shown inthe drawings conventionally at as) is used, the contact is made at intervals of one'minute (a diiferentinterval may, of course, be adopted, if desired) and'an instantaneous current flows through and energizes the coil m, thereby magnetizing momentarily the pole-pieces The armature j is first raised by the attraction of the pole-pieces is just enough to free the upper member 2' .of the friction clutch from the lower member it thereof, after which-the armature is thrown from the position shown in Fig. 4 to its initial position shown in Fig.

5. The armature j and the upper member of the clutch are loosely mounted or sleeved on the upper end of the driving shaft g and the return movement of the armature j, clutch-member 2' and push-arm n is made without affecting the driving shaft 9 and.

' through it the wattmeter a, which will continue to register.

In the modified form shown in Fig. 6, the push arm n is carried by a loose collar y which is mounted upon the driving shaft g of the meter and is held frictionally between the fast collar ordisk 2 and. a disk 2 keyed to the shaft 9 and free to'move along-the same under the influence of the coil spring 3 one end of which bearsagainst the lowerv face of the disk 2 and the other end of which bears against a shoulder t upon the shaft g. From the loose collar 3/ projects a stud or lug 5 to which is attached one end of the cord 6 the other end of which passes over a pulley 7 and is fastened to the lower end of a plunger 8 that projects into the coil 9. The loose collar 3 is driven by the friction between its upper and lower faces and the

disks

2 and 2, respectively, as the driving shaftg rotates; and it will be understood that the cord 6 is loose while the collar y is frictionally held as hereinbefore described. The latter is made of non-magnetic material and when the contact-clock 00 sends a was current through the coils and 9* at the end of-the minute-interval, the coil 9 energizes the pole-pieces 10 which pull down the disk 2 against .the tension of the spring? The energized coil 9 pulls within itself the through the plunger 8 restores the now released collar 3 to its original position. The

contact being broken, the plunger 8 drops the coil 9 may be dispensed with and the coil 9 used alone to magnetize these polepieces,

. To restore the push-arm n and the pointer Q totheir initia'l 'position at the same time,

the following devices are provided: The

contact-clock m drives the shaft 11 upon which is mounted the cam 12 formed with a shoulder 13. The cam 12 makes one revolution every twenty-four hours and at the end of each "hour it is advanced one twentyfourth of a revolution, its motion of rotation :being a step-by-step motion and not a motion of uniform rotation; in this way a quicker movement and more sudden action of the cam 12 is obtained. The free end of each of a pair of contact-plates l4: bears upon the cam surface of thecam 12 and these contact-plates are each provided with a contact-block l5fBelow the contact-plates 14: is arranged symmetrically with respect thereto a contact-plate 16 provided with a cross-bar 17. The base of an L-shaped piece of insulation 18 extends under the lower contact-plate 16, while the upper end of the insulation 18 is attached to one of the upper contact-plates 14. In this way the lower contact-plate 16 is prevented from falling away from the upper contact-plates 14:, and at the same time it is free to approachthe latter at the proper time.

plates

14, 16 are each pivotally mounted at one end, as shown in Fig. 2. Between each of the upper contact-plates 14 and the frame-plate 19 are interposed coil springs 20 which tend topull the contact-plates I 14. downwardly and keep their free ends in rub-' bing contact with the cam 12. To the lower contactplate 16 is attached the upper end of a connecting-rod or pitman 21 the lower end of which is connected to a wheel 22, which through the speed-increasing train of

toothed wheels

23, 24, 2l shown in Fig. 2 drives the shaft 25 upon which is mounted a fly wheel 26. The latter may be replaced by or used in connection with a fan 29. As

The contactthe cam 12 continues to rotate in the direction of the arrow in Fig. 2, the shoulder 13 pull the contact-plates l4: downwardly until H the contact-blocks 17 makes electrical con- 7O plunger 8," while simultaneouslythe coil 9 inspection of tact with the cross-bar 15, whereby the circuit will be closed at this point and current *will flow through the coils u and m, ener- 7 gizing the pole-pieces t and 7c, and throwing 5 the "armatures and the attached pointers q and n to their initial position. The flywheel 26 by its inertia will delay the separation of the lower contactplate 16 from the upper contact-plates 14 and will allow the 1 current .to flow fora longer time than it 20 mand made by the consumer during that period, such maximum demand being taken as the highest consumption of electrical energy in one minute during the period. But it will be understood that the pointer Q may not be restored to its original position until the end of any other desired period, as a week, a month or a year,-

Instead of taking the maximum demand as just described, it may be taken as the average of the highest daily consumptions of electrical energy in one mmute (or the average of the highest oneminute peaks) during any stated period, as one month. In order to adapt my new meter to give such an average highest daily consumption, the

armature's is formed at its upper edge with ratchet teeth 31 and a pointer-carrying shaft 32 is provided (Fig. 1) the lower end of which is monntedffree to turn'in a socket 33 I formed in the upper end of the shaft 1 upon which is fastened the armature s. The pointer-carrying shaft 32 carries at its upper end a pointer or hand 34, and near its lower end a pairof dogs or pawls 35 pivotally mounted on opposite sides of the boss 36. Further, the shaft 32 is provided just below the dial w with a pinion 37 which drives the toothed wheel 38 upon the shaft 39 upon the upper end of which is mounted above the dial to a pointer 10. "During the outward travel of the pointer q as the latter is driven, through the push-arm n, by the 'wattmeter a, the pawls 35 ride idly over the rat het teeth 31; but during the return movement of the pointer g at the end of the 24-hour period, as hereinbefore described, the pawls 35 engage the'teeth 31 and through such engagement the armature 8 turns the pointer-carrying shaft 32 through an arc equal to that traveled by the pointer q dur ing its outward (and, of course, its return) movement. The pointer 34 will travel in a clockwise direction and will, in conjunction with tl pointer 10, give the sum of all the daily "highest power -demands during any one minute; and this sum divided by the number of days in the month willgive the average of the daily highest power-demands for one minute (or the average of the highest one-minute peaks) upon which the consumers bill will be based for that month. By suitable reducing gears, (not shown herein) the movement may be made to indicate directly one-thirtieth of the sunr of the greatest outward movements of the pointer q in one minute and thereby to give the average of the higli- .est one-minute peaks durmg a period of thirty days.

In some contracts between the producer of the pointers 3a and 40' and the consumer, it is stipulated that the consumer shall pay in any event for a certain minimum whether furnished or not; and if this minimum be exceeded, then the consumer pays (1) at the rate of the highest demand for electrical energy during any one -minute within the period fixed by the agreement, or (2) at the rate of the average of the daily highest demands during the oneminute intervals in such'period. To provide for the first of these two cases just described," a stop pointer 11 is provided the index end of which extends beyond the graduated limb and edge of the dial w and lies between the zero of the outer scale and the index end 7) of the pointer 9. (Fig. 7). It will be obvious that if the push-arm n during any one-minute interval travels beyond the reading for which the stop pointer ll is set, it will carry the pointer g with it beyond that reading and the pointer will by its position at the end vof the period which has elapsed since the last resetting indicate the maximum power-demand in one minute during that period; and it will also by this position when compared with the set position of the stop pointer 41, give the excess of this maximum power-denmnd over that for which the customer must in any event pay The excess power-demand so determined will furnish a basis for the amount charged the consumerlfor the period.- In the second case of the two just described, the pointers 3t and 10 are provided, as hereinbefore described, and they will give by their readings the sum of the daily excess power-demands over the fixed minimum determined by the position of the stop pointer 41. By dividing the sum so found, by the number of days in the period (as a week, a month or a your) elapsed since the last reading, or period fixed by the contract, the average daily-0y cess demand for that period is determined In case the contract requires a higher rate to be paid for an excess demand or one higher than a certain load maximum named in the agreement, the following devices are provided: The base or shank end of the and loosely mounted upon the lower end of displacement of the toothed-wheel 43, N being the multiplier which measures the in creased rate at which the consumer must pay for the demand in excess of the maximum to which he is entitled at the regular rate.

' The toothed-wheel 43 is formed with ratchet teeth 50 upon its upper face, and above the latter is mounted a guard-plate 51 which is manually adjustable. As is best shownin the plan view inFig. 10, the guard-plate 51' does not cover all the ratchet teeth 50. In the initial position of the push-arm n the dog or pawl 42 rests upon the guard-plate .51. At a certain point in its travel determined by the setting of the guard-plate 51, the pawl 42 will ride olf the guard-plate 51 and will engage the ratchet-teeth 50 and drive the train of toothed-wheels 43 to 48. The point at which the pawl 42rides off the guard-plate 51 is that which marks the maximum power-demand to which the customer is entitled without extra charge; and the demand in excess of this maximum is charged for at a rate N times the regular rate or rate at which the power is charged for below this maximum. It will be noted that the travel of the pawl 42 beyond the edge of the guard-plate 51 produces an are edge.

displacement of the pointer 34 (N1) times the amountof such travel or displacement of the pawl 42 itself beyond the said Vhen the pointer q is returned to its initial'position against the pointer 41, the pointer-carrying shaft 32 is by the dogs 35 driven through an equal arc, as hereinbefore described, whereby the pointer 34 is moved through the same are.

From this arrangement of parts it follows that the total displacement of the pointer 34 (that produced by pawl 42' plus-that produced by the dogs 35) will be N times the displacement of the pointer 9 beyond the point which measures the maximum amount of power which the customer is entitled to demandunder his agreement without incurring the increased rate. The set pointer 41 may be dispensed with insome cases and'theguard-plate 51 used alone. In that event the pointer gwill travel from zero position and the travel of the dog 42 will be idle, until it rides off the edge of the guard-plate 51. The edge of the guard-plate is set for the maximum power-demand the customer is entitled to make without incurring the increased rate.

an increased rate will be different; and it is sometimes provided that the excess powerdemands shall be charged for at dilferent rates, according to the particular day or the particular hour of the day on or at which the excess power-demand was made. To

meet these cases the guard-plate will be moved periodically within the specified limits, either through a clock or an electromagnet the circult of which will be opened and closed l y a contact clock. The limits of the motion and the time thereof may be varled from day to day by a suitable ar rangement of theposition and of the shape of the clock contacts and of the tripping arrangement between the clock and the guard-plate 51. Thus, (referring now to Flgs. 1 and 8,) there is shown a pair of

toothed disks

60, 61, mounted free to be ad- JIlStGCl relatively to'f'each other upon ashaft 62, which is driven by a clock 63. The teeth 60', 61, of the disks ;60, 61, respectively, are formed with cam surfaces. Against the toothed peripheral edge of the cam-disk 60 is pressed, by a coil-spring 64, a shifting-rod 65 mounted freeto slide in the guide-plates 66 formed at one end with a lug 67. Similarly, a shifting-rod 65 is pressed by a coil-spring 64 against the toothed peripheral edge of the cam-disk 61, is mounted free to slide in guides 66 and is formed with a lug 67. The guard plate 51 is carried by a hub or collar 68 (Fig. 1 which is provided with a pair ofstuds 69, 69, with which are adapted to engage the lugs 67, 67, respectively. When the inner end of one of the shifting-rods rides off from one tooth onto the next Succeeding tooth, the lugat its other end engages one of the studs on the collar or hub .68 of the guard-plate 51 and moves the latter on its shaft 1".

Referring to Fig. 11, there is shown an electrically-controlled device for. shifting the guard-plate 51", wherein a slidable shifting-rod or plunger-rod 65 is mounted in guides 66, is provided with stop-

lugs

72, 72 and carries a cylindrical mass or block of metal 73 which serves as a plunger-core for the electromagnets 74, 74. The latter are alternately energized and deenergized by a contact clock 75 on the shaft 76 of which the cam-disks 77, 77 are mounted tree to be adjusted relatively to each other. @n the graduated bar or scale-bar 80 are slidably mounted the posts 7 9, 79* the lower ends of which are provided with setscrews 82 for fastening the posts in their adjusted position and "against the upper ends of which are adapted to strike the

stoplugs

72, 72, respect-ively.- The shitting-rod or plunger-rod is connected at one end by a link to'an ear 69 formed on the hub 68 of the guard-plate 51"; and the limits of movement of the plunger-rod 65*, which shifts the latter and controls the limits of the latters oscillations, are varied by moving the posts on the scale-bar 80. The electromagnets 74:, H, are controlled by the cam-disks 77, 77, respectively.

The great utility of the delayed-action circuit-breaking devices shown in Fig. :2 will be clearly understood, when, attention is called to the fact that, in order to move the pointers 3st, 40, the current must. be made to flow through the coil u an appreciable time to maintain the magnetic field which causes the rotation otthe armature s and through it or the pointer-carrying shaft 82, in restoring the pointer g to initial position.

7 It will be observed that the resetting of the pusharm n and the pointer g, together with the indicating mechanism connected with the latter, is accomplished at a time when the wattmeter is free from connection with the indicator, whereby all countertorque upon the wattmeter shaft Z) is practically avoided. To accomplish this desirable result, the connection between the wattmeter and my indicator is a clutch connection; and the armature attached to one of the clutch members is cupped (Fig. 9) to obtain a combination of a lifting and turning action by the pole-pieces which lie somewhat above the center or middle line of the armature 7'. The latter is formed with the pointed ears j and the pole-pieces 7c are pointed, whereby it is insured that the push-arm will return accurately to Zero position upon resetting. By reducing the magnetic material near the ears j to a minimum the path of the lines of force is so controlled that a rotation through an angle of at least one hundred and twenty degrees is obtained.

A loose pointer 55 is mounted above the dial w and its index end projects (as in the case of the tight-fitting hand 41) beyond the edge'thereof and into the travel path of the end 1) of the pointer 9 (Fig. 7).. The loose pointer 55 will register the maximum power-demand made during the time the indicator has been in use. is connected with no resetting mechanism. To revent its accidental displacement by friction of the adjacent rotating parts or otherwise, its base or hub 56 is formed with ratchet teeth 57 with which is adapted to engage the toe of a pawl 58 pivotally The pointer 55 mounted 'on the pointer 8st, should the pointer 55 start to move in a retrograde direction.

I claim:

1. In a meter of the class described, the combination with a wattmetcr and means for indicating the maximum power demand during a given interval of time, of a friction clutch which operatively connects said wattmeter and means; and an electromagnetic device for restoring said means to their initial position and simultaneously releasing said clutch, whereby counter-torque upon the wattmeter isavoided.

2. In a meter of the class described, the combination with a wattmeter and means for indicating the maximum power demand during a given interval of time, of a twopartclutch which operatively connects said watt-meter and means; a cupped armature attached to one of the parts of said clutch; and electromagnetic devices for raising and turning said arinat'ure to release said clutch and restore said means to their initial position. Y

3. In a meter of the class described, the combination with a wattmetei and means for indicating the maximum power demand during a given interval of time, of a twopart clutch which operatively connects said wattmeter and means; an armature formed with ears and attached to one of the parts otsaid clutch; and electromagnetic devices for raising and turning said arn'lature to release said clutch and restore said means totheir initial position, said ears insuring that the finalposition of said means will be accurately at their zero.

at. In ii'meter of the class described, the combination with a suitable device bearing graduations, of. a pointer movable relatively thereto; a device for actuating said pointer during a given interval of time; and electrically-controlled devices for restoring said 5. In a meter of the class described, the combination with a suitable device bearing graduations, of a pointer movable relatively thereto; a device for actuating said pointer duringa given interval of time; means for returning said pointer to its initial position from the position of its maximum displacement therefrom during a given period; and means for indicating the sum of such maximum displacements.

G. In a meter of the class described, the combination'ot' a wattmeter; a maxinnundemand indicator; a positioner which is actuated by said wattmeter and which positions said indicator; a pointer-positioning shaft; mechanism which connects said indicator with the latter; and resetting means for restoring said indicator to its initial position; said indicator through said mechanism driving sai'dshatt in one direction.

device and pointer to their initial position.

7. In a meter ofth'e class described, the combination wlt-h a dial; of a max mum- -demand indicator; a wattmeter; a positioner whiclris actuated by the latter and which positionssaid indicator; and a stop-pointer which is adapted to be set with respect to said dial and to intercept said indicator when the latter is moved to its initial position thereagainst; the movement of said positioner being idle until the maximum demand exceeds that for which said stoppointer is set. y

S. In a meter of the class described, the

combination with a dial; of a maximumdemand indicator; a wattmeter; a positioner which is actuated 'by the latter and which positions said indicator; a stop-pointer which is adapted to be moved over said dialand to intercept said indicator, the movement of said positioner being idle until the maximum demand exceeds that -.for which saidstop-pointer is set; a pointer-positioning shaft; mechanism which connects said.

indicator with said shaft; and. resetting means for restoring said indicator to its initialposltion; said indicator through said mechanism driving said shaft in one direccator for driving saidshaft; and a guard which keeps said mechanism inoperative during a part of the travel of said indicator.

10. In a meter of the class described, the combination with a"dial; of a maximumdemand indicator; a wattmetcr; a positioner which is actuated by the latter andwhich positions said indicator; a stop pointer which is adapted to be moved over said dial and to intercept said indicator. the movement of said positi oner being idle until the maximum demand exceeds that for which said pointer is set; a pointer-positioning shaft; mechanism driven by said indicator for driving said shaft; a guard which keeps said mechanism inoperative during a part of the travel of said indicator; resetting means which restore said indicator to its initial position; and connecting devices which connect said indicator to said shaft during the time said resetting means operate, said devices being independent of said mech anism. T

11. In a meter of the class described, the combination with a dial, a maximum-demand indicator and a positioner for the .latter;' of a pointer'positioning shaft; meets anism driven by said indicator for driving said shaft; and aguard which keeps said mechanism inoperative during a pait of the travel of said indicator.

12. In a meter of the class described, the

combination with a maximum-indicating pointer, of a pair of pawl-and-ratchet mechanisms, one of which is driven by said.

5 anisms.

13. In a meter of the class described, the

combination with a maximum-indicating pointer, means for actuating the same, and means for. resetting the same, of a device for adding the displacements of said pointer and indicating their sum.

1%. In a meter of the class described, the combination with a maximum-indicating pointer, of a pointer-carrying shaft; and means driven by said pointer for giving to said shaft a rotary movement, said'pointer driving said shaft by'both its forward and return movements. I

15. In a meter of the class described, the combination with a dial, a maximum-demand indicator and a positioner for the latter; of .a pointer-positioning shaft; mechanism driven by said indicator for driving said shaft; a guard which keeps said mechanism inoperative during a part of the. travel of said indicator; and connecting devices which couple said indicator to said shaft during a part of the movement of said indicator. r

16. In a meter of the class described, the combination with a dial, a maximum-demand indicator and a positioner for the lat-' 17'. In a meter of the class described, the I combination with a dial, a HlflXill'llllD-ClG- mand indicator and a positioner for the latter; of a pointcr-positioning shaft; mechanism driven by said indicator for driving said shaft; a guard which keeps said mechanism inoperative during a part of the travel of said indicator; and connections which couple said indicator to said shaft during a part of the movement'of said indicator and which are out of gear while said mechanism is operative.

18. In a meter of the class described, the combination of a wattmeter; a pointer;

electromagnetic means for displacing -said pointer; means for prolonging the flow of current through said electromagnetic means;

mechanism actuated by said wattmeter for determining the displacement of said pointer; and electromagnetic means for disconnecting said mechanism from said Wattmeter while said pointer is being positioned.

19. In ,a meter of the class described, the combination of a Wattmeter; a pointer; electromagnetic means for displacing said pointer; means for prolonging the flow of current through said electromagnetic means; mechanism actuated by said Watt-meter for determiningthe displacement of said pointer; and electromagnetic means for disconnecting said mechanism from said Wattmeter and'restoring the former to its initial position while said pointer is being positioned.

20. In a meter of the class described,

the two undersigned Witnesses.

the combination of a maximum-indicating pointer; a device for displacing the same, said device being free to be reset to its initial position without moving said pointer from its displaced position; a wattmeter for actuating said device; electromagnetic means for disconnecting said Wattmeter and device and then resetting the latter to its in- VLADIMIR KARAPETOFF.

Witnesses: v

HENRY H.- NORRIS, H. DIEDERICHS.

presence of