US1140925A

US1140925A - Electrical measuring instrument.

Info

Publication number: US1140925A
Application number: US48865209A
Authority: US
Inventors: Thomas W Varley
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1909-04-08
Filing date: 1909-04-08
Publication date: 1915-05-25
Anticipated expiration: 1932-05-25

Description

T. W. VARLEY.

ELECTRICAL' MEASURING INSTRUMENT.

APPLlcATroN FILED APR.8,1909.

1914:@99250 Patented Muy 25, 1915.

@Witnesses M mijn Ue u Toi THOMAS V7. 03F NEW YURK, BT.

AND MANUFACTUEKN@ COMPANY,

' MECTMCAL ELIESUECN@ ENST'JUMENT.

melones.

@wenas ai naar Patenten nay es, iena Application lerl April t3, 18W. erlal Ito. @8,65%

T all w71 om it may concern:

Be it known that l, TrroMAs W. Vannini', a citizen of the United States, residing in the borough of Manhattan, city, county, and State of New York, have invented a new and useful Improvement in Electrical Measuring lnstruments, ot which the following is a specification.'

llly invention relates to electrical measuring instruments of that class wherein advantage isltaken ot a magnet causing a substantially constant magnetic ield, in combination with stationary and movable conductors so disposed that a current passing through the stationary conductor will shift or distort the lines ot force ot the magnet, preferably without altering the total of such lines, in such manner that they Will cause a torque on the movable conductor, the function ot the stationary conductor being simply to shift the lines ot force of the magnet. and not necessarily to create the magnetic field itself, as in the ordinary electric dynamometer.

ln the following ll have described, with reference to the accompanying drawings, a structure illustrating one embodiment of my invention. the features thereoii being more particularly pointed outl hereinafter in the claims.

in' the drawings, Figure l is a vertical sectional view of a structure designed to be used as a Watt-hour meter. Fig. 2 is a cross sectional view of the structure shown in Fig. l along the line A ll, illustrating the electrical connections thereto in diagrammatic torni. Fig. 3 is a perspective view of one torni ot movable conductor.

Similar numerals of reference indicate similar parts throughout the several views.

l represents a substantially constant magnet, hereshown in the 'form of a permanent magnet, having

poles

2 and 3 carrying pole pieces el and 5 respectively. lrflach of said pole pieces and 5 is slotted as at 6 and 7 to form polar projections 8 and il, and l0 and ll respectively.

l2 represents a container made of anv suitable insulating material, such as molded vulcanized rubber, adapted to tit Within polar projections 8, 9, l@ and il and to be supported in snch position in any suitable manner, as on bracket i8 supported from poles f2 and 3.

llis a central upright tube, preferably made ot' the same material as container 12 and fog the inner Wall of the same.

l5 represents a. core, preferably of soft iron, provided with a covering 16 to electrically insulate the core from carrying current as hereinafter described. Core may be supported on tube 1t in any suitable manner, as by threading it on the same as shown.

17 represents a cup, preferably of copper, supported from shaft 18 and dipending into container 12. Shaft 18 nds a bearing at 19 on bracket 13 and at 20 in bracket 2l suitably supported upper end of shaft 18 is provided with a gear Wheel 22 engaging ear Wheel 23 on shaft 2li adapted to drive indicator 25. @up 17 is preferably slotted to form segments 26, as shown, said slots being preferably iilled with an insulating material 27, such as rubber, to form a smooth periphery.

28 represents a second cup depending from cup 17 and made preferably ot a nonmagnetie material such as aluminum. Cup 28 is provided With a covering 29 adapted to insulate the cup against electric currents preferably at all points.

30 represents a conducting uid, such as mercury, adapted to ll container lf2, preterably to a point above the height or the core l5.

8l, 32, 33 and 34.- are conducting points passing through the Walls of container l2 preferably at a point below the pele piecesV and preferably located equidistant from each other and L15 degrees from a line drawn through the centers of

slots

6 and 7.

represents a suitable source of current, shown here as a direct' current generator and 36 and 37 the mains:

38 and 39 are taps taken on the mains, 38 leading to the fixed conductor, here shown as windings or coils d0, Lil, l2 and i3 on polar projections l0, il, 9 and 8 respectively, and thence through resistance et to tap 39 and main 37. y

Main 36 as illustrated, passes through resistance to one side ot load fin. Main 3'? leads to the other side of load 46. @n either side or resistance 4:5 are taps il and 48, tap el divides as at i9 and leads to conducting points 3l and 33 and tap 4:8 divides as at 5@ and leads to conducting

points

32 and 34.

The function of the fixed coils is to distort or shitt the lines or force ot magnet l, the amount et such distortion varying as on

poles

2 and 3. The l a watt-hour meter as the resistance of mercury is' greater than that of copper.

the voltage of the load, resistance 44 acting as a resistance to fix the amount of shift for a given voltage.

The function of resistance 45 is toact as a load shunt and gives a drop of E. M. F. across its terminals varying as the current to the load. This drop causes current to fiow through

taps

47 and 48 and conducting

points

31 and 33 and 32 and 34 respectively into the mercury 30, through the mercury to the cup 17 where it passes up segments 26 at diametrically opposite points across the top of the cup and down other segments 26 diametrically opposite each other and midway the circumference of the first two segments. omitted in lwhichvcase all the load current will pass through the conducting points as stated.

The function of cup 28 is to act as a retarding element, the amount of the retarding force varying as the speed of rotation as it rotates in the constant field and induced currents are set up in it. Cup 17 because of the method of use with diametrically opposite points connected together, can o act as a retarding element and cup 28 be omitted.

1t is obvious that all of the current passing through the conducting points will not pass up the segments opposite the point but a portion of 'the current will divide and some of it pass up other adjacent segments and some of it pass around through the mer- Y cury and out of the nearest conducting.

points, but such Aoperation will not-interfere with the function of the instrument as The amount of torque exerted on the moving conductor will vary as the current owing in it and the amount of shift in the constant lield, these two elects varying .first as the current to the load and second as the potential of the load, that is, the product is the watts of the load. The combination of this torque with the retarding torque forming a watt-hour meter. v

The insulation on cup 28 and core 15 prevents current from owing through them which would result in a partial short circuiting of the conducting points.

The principle of the invention'as shown and described is applicable to either alternating or direct currents and may be utilized in the construction of voltmeters and ammeters, as well as in either integrating or indicating wattmeters, as is clear to anyone skilled in the art.

It is obvious that the detailsillustrated may be considerably varied and parts and functions transposed' without departin romthe spirit of my inventionas, for instance, Varying the number of polesor polar projections or the number of windings of Resistance 45 may of course be the stationary conductor or the number of segments of the movable conductor, or transposing -the functions of the stationary and mable conductors.

I'do not restrict myself to any of the details as shown and described.

Having described my invention, what l claim and desire to secure by Letters Patent is:

1. A measuringinstrument for an electric circuit comprising a permanent magnet, a stationary winding surrounding parts 'of the said magnet and connected in shunt relation to the said circuit for shitting the lines of force in the said magnet, a rotatable member adapted to respond to the shifting of the lines ot force, a chamber within which the said rotatable member is located, a plurality of contact terminals mounted in the peripheral Wall of the said chamber, and a liquid conductor in the said chamber between the said contact terminals and the rotatable member.

2. A measuring instrument for an electric circuit comprising a permanent magnet,- a stationary winding surrounding parts of the said magnet and connected in shunt relation to the said circuit for shifting the lines of force in the said magnet, a rotatable member adapted to respond to the shifting of `the lines of force, a retarding element adaptedto move with the said rotatable member, a chamber in which the said rotatable member is located, a'plurality of uniformly spaced contact terminals mounted in the peripheral wall of the said chamber, and a liquid conductor in the said chamber between the said contact terminals and the rotatable member.

3. An electrical measuring instrument comprising a substantially constant magnet, a stationary conductor adapted to shift the lines of force'set up by said magnet, a movable conductor adapted to respond to the shiting'of said lines of force, a chamber within which said movable lconductor is adapted to rotate, contact terminals in the wall of said chamber, a liquid conductor 1n said chamber between said contact terminals and the movable conductor and a retarding element moving with said movable conductor but insulated from said liquid conductor.

4. In an apparatus of the character described, a movable conductor comprising an inverted cup of conducting material having a solid u per end and a peripheral Wall comprising a set of uniform-ly spaced fingers va peripheral wall composed of a set of spaced fingers and insulating material interposed between said lingers, opposltely disivieoeae posed contact terminals adjacent to said movabe conductor and an eiectricai conductor between said contact terminais and said inovabie conductor.

6. in an apparatus of the character described a movable conductor comprising an inverted cup ot conducting material having; a solici upper end and a peripherai Wait comprising a set of integrai fingers and interposed insulating strips of approximately the same width as the ingers.

't'. An eiectricai measuring instrument comprising a substantially constant magnet a stationary conductor adapted to shift tine lines of torce set up by said magnet, a movabie coduetor comprising a cup of conducting material having its side waits divmeti into segments and adapte@ to vresponc't to the shifting of said lines ot force, a inercury chamber within which saici movable conductor is adapted to rotate, mercury in.

said chamber and Contact terminals in the wall of saici` chamber7 the mercury forming` e conductor between said contact terminate anni sai movabie conductor.

8. A measuring instrument for an eiectric circuit comprising a permanent magnet, a stationary Winding thereon connected in shunt relation to the said circuit for shifting; the lines of torce in the said magnet, a movabie conductor comprising an inverted cup oi conducting material having a soiioi upper emi anni a peripheral Wall comprising a set of integral fingers and interposed insulating strips, anti means fior providing the said movabie conductor with current proportional to the current traversing the said ciru cuit.

iin testimony whereof have signed. this specication in the presence ot two subscribing Witnessen THMAS W. VA'RLEY.

Witnesses:

Snanonr C. Masuren.,