Зображення сторінки
PDF
ePub

formed by clamping the case to the wheel and slowly turning the two, this being one of the duties of the erecting engineer, who is provided with proper instructions regarding the number of turns, size of wire, etc. The field magnet coil and case do not, of course, revolve in the completed machine, but are supported and maintained stationary. It will be noticed that this field coil does not entirely fill the case radially but allows the frame to form a considerable flange. The object of this flange is to provide a support for the armature coils, c, or more properly

cases, between the outer and inner supporting rings, continued entirely around the circle, and on both sides of the machine, provides a seat or double stirrup for the field magnet coil and case, and at the same time locks the armature coils in position. Any individual coil case, however, can be easily removed by taking out the one screw, which fastens the case to the stationary supporting ring.

From the above description of the various details of the machine, the reader has no doubt by this time gathered that it

[graphic][subsumed][subsumed][ocr errors][merged small]

speaking, armature cases, G, to which in turn is secured a supporting ring.

There are 112 armature bars, the number corresponding with the number of pole pieces. These armatures are built up of punched laminations of No. 28 or 30 sheet iron. The laminations are clamped together by means of three insulated bolts, the two end bolts being longer than the middle one, for the purpose of securing the armatures to the supporting ring, as clearly shown in Fig. 3.

The armature coils are rectangular in shape, wound on a suitable form, insulated, taped and completely embedded in protecting cases, G, G. These cases, the designers say, can be

[blocks in formation]

consists simply of a multipolar field having a single exciting coil, all the polar projections on one side being of the same polarity. The magnetic circuit from one pole to the oppoite one is closed by stationary armature bars on the ends of which are mounted the armature coils. It follows that the arrangement of the armature coil connections is susceptible of a great many variations, making it possible to readily adapt the machine to high or low voltage, so that the circuits may be divided to suit existing requirements.

Following are the principal data for a 200 k. w. machine : Speed, 134 r. p. m.; power required, 275 h. p.; current, 182; E. M. F., 1,100 volts; frequency, 125; diameter of wheel over all, 17 feet, 4 inches; diameter of wheel at face, 15 feet; width of wheel over all, 30 inches; thickness of rim, 44 inches; diameter of shaft, 12 inches; radial length of pole-pieces, 144 inches; section of polepieces, 3 inches by 7 inches; number of pole-pieces, 112; total moving weight exclusive of shaft, 36,360 pounds; peripheral speed of rim, 6,312 feet per minute; centrifugal strain on rim, 21 pounds per square inch; centrifugal strain on spokes, 4,024 pounds per square inch; weight of field magnet and case, 4,275 pounds; weight of armature bars, 7,460 pounds; weight of armature coils and cases, 1,440 pounds; weight of supporting rings and lugs, 3,500 pounds; weight of copper wire in field and armature, 4,833 pounds; total weight of machine, 53,035 pounds.

FIG. 2.-MAGNETS AND ARMATURE OF WARREN ENGINE DYNAMO.

made of wood, fibre, porcelain, glass, slate or any material which can be easily formed or moulded, and possesses high insulating qualities. The coil cases are attached to the supporting ring by means of screws. The back surface of the coil case is recessed to within 4 inch of the face, this recess being of such shape, and so located that the case caps over the end of the armatures bar. It will be readily seen that the arrangement of the coil

GENERAL ELECTRIC AFFAIRS.

The annual meeting of the General Electric company was held at its offices in Schenectady on April 10. Proxies on a very large block of stock were voted by Oliver Ames, 2d, of Boston and the old board of trustees of last year was reëlected. The date of the stockholders' annual election was changed from the second Tuesday in April to the second Tuesday in May. The fiscal year ends December 31. The number of directors was changed from eleven to thirteen. No election of officers took place. From conversation with some of the directors it was inferred that they would be the same as last year, and that the election would take place in New York. It is understood that the officers are to give their early attention to a reorganization in order to reduce the capital stock to the value indicated by the loss of over $12,000,000 last year, as shown by the balance sheet lately made public.

NEW YORK-WASHINGTON ELEVATED ELECTRIC RAILWAY. A bill has been introduced in the House of Representatives at Washington by Mr. Catchings of Mississippi, contemplating the building of an elevated electric railway from this city to Washington. The capital is placed at $15,000,000.

THE NEW BALL & WOOD VERTICAL COMPOUND ENGINE.

The Ball & Wood Company, of 15 Cortlandt street, this city, have just completed at their Elizabeth works a new type of vertical compound engine which is believed to embody a number of original and valuable features. At the invitation of the company a number of prominent engineers were present at the private "trial trip" of this engine on March 31, and it is with pleasure that we now give a detailed and illustrated description, the data for which was unavailable at that time.

The engine, a front view of which appears here, is of 600 h. p.,

to about 100 revolutions per minute, or less, but in this engine the automatic cut-off is obtained by independently operated cut-off valves placed inside the steam valves, and actuated by a specially designed governor. This arrangement places no restriction on rotative speed, which is decided by other considerations, and the aim has been to find a medium unobjectionable to the slow speed advocates.

The governing mechanism of the engine is of special interest to the student of valve gears. Beginning with a well-known form of shaft governor, the principles of which have attracted the attention and admiration of the ablest engineers of the day, the superb regulation thus obtained is made effective by transmitting

[graphic][subsumed][subsumed][merged small]

non-condensing. The cylinders are 19 and 31 inches in diameter with a 24 inch stroke, and the engine runs at 150 revolutions a minute with 125 pounds initial pressure. The best steam distribution is obtained, it is thought, with some form or modification of the Corliss wrist plate motion and valves, and the smallest possible clearance is obtained by placing these valves in the cylinder heads. This arrangement, then, has been adopted in the engine under consideration.

The Corliss releasing gear practically limits the rotative speed

the necessary motion to the cut-off valves through a special wrist plate device, in which a compound motion is obtained, and the cut-off valves at all points of cut-off operate relatively to the main valves just as though the latter were standing still, thus preventing wire-drawing of steam at any point of cut-off.

The location of the valves in the cylinder head, giving as it does the shortest possible ports, admits of their being of ample capacity without an appreciable increase of clearance.

The peculiar motion of the cut-off valve utilizes these wide

ports to the fullest possible extent, and the cut-off motion at every point from zero to three-quarter stroke is a rapid one, in fact as rapid as is obtained from the releasing gear, because of the higher rotative speed of the engine.

Another feature of great importance in this gear, particularly with compound engines, or where moments of excessive overload occur, is its ability to cut off at three-quarter stroke, while the Corliss gear is limited to about half-stroke.

While this engine is eminently suited to any service requiring stationary engines of the highest efficiency, it has special features of adaptability to the work of driving dynamos built upon the engine shaft and free from any encumbrance. The one described, the first of its type, is intended for this service in the station of the Chicago Edison Company.

Trade Notes and Novelties

AND MECHANICAL DEPARTMENT.

NEW YORK NOTES.

J. JONES & SON, 67 Cortlandt street, notify the trade that they have bought from the receiver the stock of Alexander, Barney & Chapin, now in his hands at the above address, to which point they are removing. The stock was bought for cash and is valued at over $10,000.

THE STIRLING BOILER Co. have just issued a very meaty list of recent sales all over the country, aggregating several thousand horse power. In several instances the orders are the seventh, eighth or ninth from the same concerns. Topping the list is one of 1,500 h. p. from the McCahan Sugar Refining Co., of Philadelphia.

MR. JAMES I. AYER, E. E., formerly manager of the Municipal Electric Light Co., of St. Louis, and ex-president of the National Electric Light Association, has accepted the general managership of the Royal Arc Electric Co., owning the Howard incandescent arc light patents and system. Both parties are to be congratulated. Mr. Ayer will be a welcome addition to the electrical circle of New York city.

DIXON'S GRAPHITE CYCLE LUBRICANT.-The Joseph Dixon Crucible Co., Jersey City, N. J., are putting a Cycle Chain Graphite on the market. The graphite is not only of the choicest stock, but is ground to an impalpable powder, and then reground with a high grade of lubricating oil. This material, when applied to the chain of a bicycle, penetrates the bearings and thoroughly lubri cates and protects them from wear and rust. The Dixon Company will shortly put the same material on the market in the form of a solid stick.

THE UNITED COLUMBIAN ELECTRIC CO., 280 Broadway, New York, have just issued a very neat pamphlet in regard to their improved twin series railway motor, well illustrated, and devoted to a discussion of the reasons why street railway companies should equip their cars with twin series motors. This is accompanied by some details of a test made on the Union Railway, New York, showing a notable economy for the twin motor over other forms and makes, and figuring out a saving of $250 per car per annum. There is also a neat testimonial from the Suburban Rapid Transit Street Railway Co., of Pittsburgh.

WESTERN NOTES.

THE SUNBEAM LAMP MFG. Co., of Chicago, are permanently located in the new Chicago Title & Trust Bldg., 100 Washington St.

THE GRAFF TELEPHONE Co., Chicago, was incorporated last week by Ed. D. Hoy, Calvin W. Ream, Wm. R. Tucker and others. The capital stock is $1,000,000.

THE WALLACE ELECTRIC Co., Chicago, are making active preparations to move to their new quarters in the Manhattan Bldg., on May 1st. They have recently added several new specialties to their line of goods.

MILWAUKEE, WIS.-The Wisconsin Telephone Co. is in trouble with its patrons over an order limiting subscribers to 1,000 calls a year and charging 2 cts. for every call in excess of that number. It is alleged that a large number will abandon the use of 'phones if the company enforces the order.

MR. CHAS. BLIZARD, general sales agent of the Electric Storage Battery Co., who came to Chicago some time ago to introduce the chloride accumulator, has returned to Philadelphia, after a very successful trip, leaving the business in Chicago in the hands of Messrs. Pierce & Richardson, No. 527 Manhattan Bldg.

GEORGE CUTTER, of Chicago, has issued a catalogue of the china specialties of Pass & Seymour, for whom he is the western agent. It is well illustrated and indicates that these well known and valuable articles are to be as popular in the vicinity of Chicago as they have become here.

MR. GEO. E. FISHER, Gen'l. M'gr. of the Commercial Electric Engineering Co., Detroit, Mich., was in Chicago last week. This company are agents for Michigan, Ohio and Indiana, for the Standard Electric Co., and although established but a short time, have already closed several important lighting contracts.

THE PUMPELLY-SORLEY STORAGE BATTERY Co., Chicago, have just closed a contract for furnishing a complete battery plant for the Kent apartment building, cor. 43d and Calumet Ave., Chicago. This is to supplement the regular lighting plant consisting of Waddell-Entz direct coupled generators on Ideal engines.

CUSHING & MORSE, general Western agents of Kerite wires and cables, 225 Dearborn street, Chicago, have just issued some very effective literature in request to those time honored specialties. They also circulate neat little "sticking plaster" envelopes, for the benefit of their friends who may have cuts and bruises to be taped.

MR. GEO. L. THAYER, Chicago, has opened offices in the Monadnock Bldg., as consulting and constructing electrical engineer. Mr. Thayer's experience in the electrical field extends over a number of years; beginning as electrician in charge of the lighting plants of the C. & N. W. Ry. After graduating from Cornell he entered the employ of the Westinghouse Co., where he remained until a short time ago.

MR. W. M. LENHART, late Gen'l. M'gr. of the National Electric Manufacturing Co., Eau Claire, Wis., has associated himself with the Standard Electric Co., Chicago, as Gen'l Southern Agent at Atlanta, Ga. Mr. Lenhart's experience in matters electrical covers so long a period, and his success in the field has been so uniform as to make the introduction of "Standard" apparatus in the South an easy matter for him. THE ELECTRICAL ENGINEER wishes him the best of success and congratulates the Standard Co. on securing his services.

THE RACINE BOAT MFG. Co., of Racine, Wis., forward us a copy of their very handsome and interesting illustrated catalogue. It gives an excellent idea of the range and variety of their product, as well as of the excellence of the craft, which are in all sizes and include canoes, row boats, hunting boats, sail yachts, steam yachts, gas launches, etc. The company is now undertaking the manufacture of electric launches. The catalogue shows also the Racine automatic engine and boiler, a well-known make, and the Racine porcupine boiler.

PHILADELPHIA NOTES.

THE TECHNIC ELECTRICAL WORKS, of Philadelphia, has just completed a large order for switches for Harry S. Smith & Co., Ltd.

THE BREESE & MANSFIELD Co., the electric railway engineers, of 1120 Betz Building, Philadelphia, announce to their friends and the public that they have taken the agency for the Walker dynamos and motors.

HARRY S. SMITH & CO., LTD., who represent the Interior Telephone Co. in Philadelphia, report several sales. Among recent installations are the following: Drexel Institute, Strawbridge & Clothier, Sharpless Bros. and the Friends' Asylum.

MR. W. W. HARRISON, of the Franklin Sugar Refining Co. is about to install an elaborate steam and electric plant for his residence at Glenside, Pa. The contract for this work will include engines, boilers, dynamos, piping and storage batteries.

QUEEN & Co., Philadelphia, have for some time past given especial attention to the design of apparatus for the electrical testing of cables. Visitors to the World's Columbian Exposition will especially remember their portable cable testing set exhibited there, on account of its very great compactness. That their work in this line is being appreciated has been shown them very agreeably of late, by large orders for this kind of apparatus; the Electric Traction Co. of Philadelphia having recently purchased one, and the Philadelphia Traction Co. two, extensive sets for measurement on electric cables.

Departmental items of Electric Light, Electric Railways, Electric Power, Telegraph, Telephone, New Hotels, New Buildings, Apparatus Wanted, Financial, Miscellaneous, etc., will be found in the advertising pages.

[ocr errors][ocr errors][merged small][ocr errors][subsumed][ocr errors][merged small][merged small]

Vol. XVII.

THE

Electrical Engineer.

APRIL 25, 1894.

SMALL ARCS OR LARGE INCANDESCENTS?

T

BY

Albert Scheible

HE discussion which has recently been started on the opening for small arc lamps leads us to speculate on the apparent limitations of these as they decrease in candle power and the probable line of demarcation between them and the large incandescents. Indeed it seems to me that we are viewing but one phase of the question when we consider the small arcs alone, as many of the arguments advanced in their favor hold equally well for incandescent lamps of higher candle power than the ordinary. The shortcoming need not lie entirely in the old size of arc lamps, but may be in the whole series of electric lighting units, which shows an immense gap between the high candle arcs and the small incandescents.

The older workers who were familiar with the cry of a dozen years ago-"the subdivision of the electric light" -will remember how decided a want was met by the in candescent lamp, and how this immediately commanded the attention of electrical workers, it being even thought by some that the arc lamp was doomed altogether. And we who have watched other pendulum-like tendencies in electrical developments can see how the concentrated energy of a host of exploiters was easily turned from the large arc lamp to the far smaller incandescent, though the former has still held its own until both have come down to us side by side in their more perfected forms. Of course there have been several sizes of incandescents, more particularly the ten, sixteen, thirty-two and some of fifty candles; and there have been arc lamps of 1,200, 1,500 and 2,000 c. p.; but, after all, these represent but two series of sizes near the extremes of the scale, while there really is a demand for all the intervening sizes as well.

So we are at last confronted with the fact that the needs of electric lighting call for a graded series of units, ranging all the way from ten to two thousand candle power, there being at present a decided gap between the fifty and the thousand. That the small ares will do much towards filling a part of this gap (perhaps all that lies above three or four hundred c. p.) seems evident from the more recent developments. But I think we must look to the incandescent lamp in its larger sizes for the rest. Of course the lower efficiency of the latter as compared with the arc lamp counts against it, but the efforts now being made by various investigators promise some practical results in raising this efficiency. The prolonged litigation over the vacuum lamps has driven many lamp makers to experiments along new lines and some of their work may do much towards helping the large incandescents. What is more, the competition on the small sizes has narrowed the manufacturer's profit so much that he is on the lookout for other styles that leave him a better margin, and the few firms who are in position to supply lamps of several hundred candle power are already reaping some of the harvest. Happily, less is at present expected of these large incandescents as regards life for a certain efficiency, since they fill a line in which the consumers have not yet been spoilt. And even if the expectation of some of the experimenters -the production of a three hundred hour, one watt per candle lamp-is only partly realized, there still seems to be a good opening for incandescents in sizes up to three and perhaps four hundred candle power.

No. 312.

In this connection it is interesting to note the comments of the Edison lamp expert, Mr. J. W. Howell, on Prof. Anthony's recent paper. When Mr. Howell remarks that the 16 and not the 32 c. p. lamp represents the best lamp making of to-day, can we not infer that there is still room for considerable development of the 50, 100 and 200 c. p. lamps? Mr. Howell's comments, and indeed the whole discussion of Prof. Anthony's paper, tends to show that further perfection of the incandescent lamps may soon be expected, and I for one believe that the high candle power lamps will get some of that attention which they have long been needing. Just where the line will be drawn between them and the small arcs remains to be seen, as the developments in methods of distribution by either direct or alternating currents lend themselves equally readily to both forms. Probably it will depend partly on the result of the work already mentioned, which involves the making of the filaments as well as the nature and density of the surrounding atmosphere. At any rate, we may expect to see the incandescent lamp entitled to a good share of the medium candle-power lighting which is now being exploited, so that we should not lose sight of it amid the stir over that timely newcomer, the small arc.

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]
[merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

18. Rated capacity.

19. Mean capacity.

20. Mean available capacity.

Accompanying this is a form in which the readings of charges and discharges may be tabulated and a set of curves, given by Crompton in the Journal of the London Institution of Electrical Engineers, page 691, Vol. XIX, illustrating the subject of the above 9th division.

The first tests to be made are with a view to laying out such a set of curves. One cell should be used for each test; that is, one charge and discharge, and a curve plotted from it. Each test should be repeated with another cell. Cells for these tests should be new, and in the best possible condition.

Out of a series of discharges from five or six similar cells, at as many different rates the proper rate can be selected, and the minimum potential determined. These curves are to the storage battery expert what indicator diagrams are to the steam engineer. They show at what rate and to what potential the discharge may be made. I should say that the best rate for this cell was 22 amperes, and that the minimum limit of potential with this current flowing should be 1.9 volts. By letting it fall to 1.8 volts, an additional 25 ampere hours or 12 per cent. would be gained, but at a lower efficiency, with increased difficulty of regulation, and with detriment to the plates, both positive and negative. The best normal discharging rate may usually be adopted for the charging rate.

All the divisions of the accompanying report except the second may now be filled in without further tests. It is customary to rate the capacity at the greatest number of ampere-hours obtained by discharging at the normal rate to 1.8 volts, and this rule should be followed in the report. The mean capacity is approximately midway between the rated capacity, and the capacity of the cell at its worst. For example, a 1,000 ampere-hour cell may be used until its capacity falls to 700, and the mean capacity will therefore be 850. The mean available capacity is the mean capacity in a service where the cell is never used below 1.9 volts which would be perhaps 25 per cent. less, or 612 ampere-hours. Any other figure may be substituted for 1.9 if found to be the lowest potential at which the cell can be profitably worked. It will be understood, however, that I am here treating particularly of lead cells.

The most difficult point is division 2. It is impossible to determine from one kind of service what a battery will do in some other kind. A laboratory test of durability is

[ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][ocr errors][ocr errors][merged small][merged small][merged small]
[merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small]

interesting and may tell something of a battery, but it may also be misleading, and I would rarely recommend the consulting engineer to undertake it. For a good battery, two years at least will be required, a laboratory in which there is nothing else going on, and day and night assistants with no other duties to confuse them. It would be desirable to reproduce in the laboratory, as far as possible, the commercial conditions under which the battery is intended to be used; the charging and discharging rates, the working potentials, the specific gravity, temperatures and circula

« НазадПродовжити »