US1197092A - Dynamo-electric machine. - Google Patents

Description

T. S. ALLEN.

DYNAMO ELECTRIC MACHINE.

APPLICATION mm APR. 15. 1910.

Patented Sept. 5, 1916.

" f STATES PATENT OFFICE.

mom's. um, 01' IILWAUKEE, WISCONSIN, ASSIGI'OB, BY alarm-rs, TO muracmma comm, AOOBPOBA'I'IOI OI nmwm.

nnmo-nmc'rarc nacrmm Specification of Letters mm.

Patented Sept. 5, 1916.

' Application filed April15,1910. Q1181 Io. "5,020.

To all whom it may concern Beit known that I, Tnouas S. ALLEN a citizen of the United States, residing at Milwaukee, in the county' of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Dynamo- Electric Machines, of which the following is a full, clear, and exact specification.

This invention relates to dynamo-electric machines, and particularly to revolving field members of high speed alternators, such as turbo-generators.

In certain types of dynamo-electric machines, and particularly in rotating field members of high speed machines, parts of the coils are under high stresses whlch tend to distort and displace thecoils, and particularly the side portions thereof. These stresses are especially great in high speed rotating field members having a small number of pairs of poles, for in such machines the centrifugal force acting on certain parts of a coil may be divided into two 'components, oneof which is at right angles to the faceof the'pole and tends to shift the coil laterally from the pole, and this component may be as large or even larger than the component which is parallel to the axis of the pole and is resisted by the pole tips.

To support the coils and to prevent their displacement at high speeds, coil bracing members have been employed, and these bracing members, each of which supports and braces the sides of the coils of two adjacent poles, are usually retained in position by fastening devices extending into the core of the rotating member. Such bracing members have not been satisfactory in all respects for the reason that they add to the weight of. the machine, are frequently diflicult to apply to the coils, and to adjust or tighten, and it is often the case that the means for fastening these bracing members in position materially weakens the core.

The object of the present invention is to provide coil supporting means which relieves the coils of the st tending to shift them outwardly or laterally from the pole, which is inexpensive, light in weight, and can be easily applied tothe coils.

In carrying out my invention, I bind the coils firmly to the poles so as to relieve the side portions of the coils of the stresses, and preferably band wire is employed for this purpose, each coil-being wrapped at differing material, are placed lengthwise of ,the coil on the exterior thereof, and this band wire is wrapped tightly about these strips so that all portions of the coil are held against lateral displacement.

The invention may be further brieflysummarized as consisting in certain combinations and arrangements of parts which. will be described in the specification and set forth in the appended claims.

Reference is had to the accompanying sheet of drawings wherein- Figure 1 is a side elevation of a dynamoelectric machine having a rotating field member, the coils of which are supported and braced in accordance with my invention; Flg. 2 is an enlarged side view of one of the field magnets; and, Fig. 3 is a transverse sectional view substantially along the line 3-3 of Fig. 2.

In the figures of the drawing, 10 represents the stationary element of the machine, which in this case is an armature, and 11 represents as a whole, the rotary element which in this case is a rotary field member. The rotary member includes a core 12,which is mounted upon a shaft 13, and field magnets 14, each comprising a core 15 and a coil 16, which may be formed of any suitable conductor and with any number of layers, but as shown in Fig. 3, is formed of several layers of square conductor 17.

The radial displacement of the coils due to that component of the centrifugal force acting on each part of a coil, parallel to the axis of the pole is resisted by pole tips or other polar projections 18 provided at the free end of the pole, but unless means is provided for relieving the sides of the coils of the stresses, they may be displaced or shifted laterally or outwardly away from the pole, and when a coil is built up of several layers of square conductor, as shown in Fig. 3, the turns'at the inner end of the pole will tend to telescope with ect to the turns at the outer end. To secure y hold all portions of the coils against lateral displacement, I bind each coil ata number of spaced omts in its length by several turns of tigh y wrapped band wire 19, and pref- 'erably, I employ between the band wire and the coil longitudinally extending strips 20 which are arranged at the corners of the coil, and along the sides and ends thereof, the strips being preferably spaced apart and forming passageways therebetween, as shown in the drawings, this construction leaving the portions of the coil surface uncovered by strips open to the atmosphere. with this latter arrangement and with the binding material laid over, =the strips at spaced points, as shown in the drawings, the bearing of the binding material is distributed over the full axlal length of the coil with little or no danger of cutting into the same, and a considerable portion of the coil surface is open to the atmosphere, a condition which promoteseflicient ventilation and cooling of the coil. These strips may be formed of metal, providing the exterior of the coil is covered with a layer of coating of -insulation, or they may be formed of insulating material, such as fiber. The turns of wire in each group, three of which are shown in the drawings, may be soldered together opposite each of the strips 20, and the free ends of each group will be securely fastened so that the band wire will not become loose at any speed at which the rotary field member may be operated.

It will be seen that the coil supporting and bracing means which I have provided tending in the general direction of the turns of said coil.

2. In a dynamo-electric machine, a rotary element havlng field magnets comprising radial poles and coils mounted thereon,

means for preventing radial displacement of said coils, spaced strips extending longitudinally of the coils at theexterior thereof, certain of said strips being disposed at the corners of said coils and being made up of parts disposed at an angle to each other and engaging adjacent sides of the coils, and banding material wrapped about said strips and disposed in a plurality of spaced sections to prevent lateral displacement of portions of said coils.

Milwaukee, -Wis, April 11, 1910.

In testimony whereof I aflix my signature,

in the presence of two witnesses.

THOMAS S. ALLEN.

Witnesses:

CHAS. L. BYRON, Ros. E. LEOLL.

Images