US687992A - Dynamo-electric machinery. - Google Patents

Description

No. 687,992. Patented Dec. 3, |9l.

A. cHuncHwAnn.

DYNAMO ELECTRIC MACHINERY.

Application led Dec. 18, 1899. Renewed Aug. 14, 1901.)

um man.)

ma Noms PETERS no, PHcvc-umc. msmmmm4 u. c

UNITED STATES 4PATENT OFFICE.

ALEXANDER CHURCHWARD, OE CHICAGO, ILLINOIS, AssIeNOR To GENERAL ELECTRIC COMPANY, A CORPORATION OE NEw YORK.

DYNAMO-ELECTRIC MACHINERY.

SPECIFICATION forming part of Letters Patent No. 687,992, dated December 3, 1901.

Application tiled December 18, 1899. Renewed August 14, 1901. Serial No. 72.055. (No model.

T @u Wfl/07W may @Wwefvf separately and slip them over the poles in the Be it known that I, ALEXANDER CHURCH- many cases where the free end of the pole is WARD, a citizen of the United States, residing also enlarged oriianged and generally inat Chicago, in the County of Cook and State creases the cost of Construction in any case.

5 of Illinois, have invented certain new and The presentimprovementcontemplates the 55 useful Improvements in Dynamo-Frames, of use of separate detachable pole-pieces bolted which the following is a specification. to the frame in such manner as to meet all re- This invention relates to improvelnents in quirements as to large Contact area, but withthe frames or field-castings of dynamo-elecout the use of enlarged base-flanges, which ro tric machinery, and has for its object to prowould prevent the iield-coils from being slip- 6o vide an improved composite cast and wrought ped over the pole af terbeing separately wound. iron or steel construction for possessing both To this end I secure to the frame or field-castelectrical and mechanical orstructural advaning at the points where the poles lead off tages over the previous art in this line. It is plates of wrought-iron or steel properly prowell known that cast-iron yokes or lields give portioned to afford the necessary area of con- 65 the best results in the matter of regulation, tact with the cast-iron and then bolt said are cheaper, more easily worked, and make pole-pieces directly to these plates. Being of more perfect Castings. The permeability of substantially the same degree of permeability, Cast-iron, however, is not high enough to warthe lines of force will pass between the poles zo rant its use in many cases for the pole-pieces, and plates without undue loss and will also 7o which are better made of wrought or lamipass Without undue loss between the plates nated iron or cast-steel of higher permeabiland the cast-iron yoke or field-frame owing ity; but when such poles are used in connecto a large area of Contact between them. At tion with cast-iron frames oryokes provision the same time the removability of the poles must be made for an area of Contact at the enables the field-coils to be wound independ- 75 juncture of the pole-piece with the yoke or ently of the poles and then placed upon or held-casting much greater than the area of removed from them without difficulty whenthe pole-piece, it being clear that as cast-iron ever found desirable. is practicallysaturated at fty thousand lines In the accompanying drawings, Figure l 3o of force per square inch, while wrought-iron shows in side elevation a section of a frame or 8o or steel does not become saturated at much yoke of a dynamo-electric machine provided less than twice that amount, an area of conwith my improvement. Fig. 2 is a similar tact between the two materials equal to about view of a construction slightly modified from twice the area of the wrought-iron must be that shown in Fig. l. Fig. 3 is a side eleva- 3 5 provided in order not to overtax the capacity tion of a rotary field-Casting with its poles ap- 85 of the cast-iron. By present methods the plied in accordance with my improvement. pole-pieces are often cast into the yoke or As shown in Fig. l, A designates the castframe; but this is not always satisfactory, as iron yoke or iield-frame section, and B its the joint between cast-iron and wrought-iron wrought orlaminatediron or steel pole-pieces.

4o or steel cast into it is liable to be so poor as The latter are removably secured to the yoke 9o to require an excessive amount of copper to in any suitable manner, as by bolts b, and are force the magnetism through it and as it is herein shown as provided at their inner or .frequently desirable to be able to remove the free ends with flanges b to prevent any possipoles from the frame or yoke for convenience bility of the field-Coils slipping off them when in shipping and in erecting or repairing. It applied in the usual manner. 95 is also customary to bolt separate pole-pieces C designates the wrought -iron or steel to the yoke or frame and provide the increased plates which are inserted between the yoke area of Contact by an enlargement or llange Aand poles B. These plates are made of any at the base of the pole-piece. This, however, suitable shape and of such dimensions as to 5o renders it impossible to wind the field-coils afford an ample area of Contact with the cast- Ioo iron yoke. They are secured to the yoke by suitable bolts or screws c, and the clamping of t-he pole-pieces by the bolt b also serves to hold the plates in close contact with the yoke or frame, as Well as to hold the pole-pieces securely seated against said plates. The contacting surfaces ofthe frame,plates, and poles are trned off by planing orby boring and turning to afford a fair bearing against each other, and the eld-coils are conveniently wound separately and slipped over the poles before the latter are clamped in place. By removing the bolts l) the poles and coils may then be repaired or replaced, as desired.

In Fig. 2 the flanges b (shown at the free ends of the poles in Fig. l) are omitted, so that the field coils could be slipped over them without removing the poles from the yoke; but even in this case my improved construction is desirable. In Fig. 3 a rotary field-casting ct is shown as provided with pole-pieces Y B', which are bolted to Wrought-iron or steel I claim as my invention n l. The combination with the field-casting or frame of a dynamo-electric machine, of Wrought-iron or steel plates secured to said frame,Wrought-iron or steel pole-pieces seated against said plates, and means for securing the pole-pieces removably in position on said plates, substantially as described.

2. The combination With the Held-casting or frame of a dynamo-electric machine, of Wrought-iron or steel plates bolted to said frame or field-casting, wrought-iron or steel pole-pieces seated against said plates, and bolts applied between the frame or field-casting and the pole-pieces and passing through the plates to clamp the pole-pieces removably to the frame or field-casting with the plates intervening, substantially as described.

In testimony that I claim the foregoing as my invention I afiix my signature, in presence of two subscribing Witnesses, this lith day of December, A. D. 1899.

ALEX. OI-IURCHW'ARD.

Witnesses:

HENRY W. CARTER, ALBERT H. GRAVES.

Images