US688318A - Winding for electric machines. - Google Patents

Description

Patented Dec. l0, mm. B. a. LAMME.

WINDING FOR ELECTRICAL MACHINES.

(Application riled Apr. 30, 1001.

(No Modal.)

TOR IIEY.

UNITED STATES PATENT OFFICE.

IISENIAMIN e. LAMME, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR To WESTINGHOUSE ELECTRIC a MANUFACTURING o, A CORPORA- TION OF PENNSYLVANIA.

WINDING FOR E ECTRICAL MACHINES.

srnoIrIoA'rIoN forming sea of Letters Patent Ne. 688,318, dated December 10, 1901.

Application filed A ril 30, 1901.

Serial No. 58,206. (No model.)

To all whom it may concern.-

Be it known that I, BENJAMIN G. LAMME, a citizen of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in \Vindings for Electrical Machines, of which the following is a specification.

My invention relates to windings for electrical machines; and it has for its object to provide a winding which shall be suitable for high potentials by afiording adequate insulation and at the same time economy of space and an advantageous arrangement of conductors.

My invention is primarily designed for the stationary armatures of high-potential polyphase generators; but its use is not necessarily restricted to such specific relations.

In the accompanying drawings, Figure 1 isa plan view of a portion of a winding constructed in accordance with my invention. Fig. 2 is a detail view, partially in end elevation and partially in section, of a portion of a slotted core with conductors located in the core-slots. Fig. 3 is an end elevation of that portion of the winding shown in Fig. 1. Fig. t is a detail view of a portion of one set or group of barconductors such as are employed in connection with my present invention.

In the construction of alternating-current generators of large size and designed for. generating currents of high potential it is necessary to so arrange and connect the several elements of the windings that those portions between which there is a considerable difference of potential shall be as widely separated as is consistent with other practical considerations and at the same time be adequately insulated from each other and from the core.

In order to economize space to as great an extent as possible and at the same time to avoid danger of short circuits by reason of the breaking down of insulation, I employ a bar-winding and combine the bars into groups, so that the bar of each group shall have a minimum diiference of potential. .This arrangement enables me to locate the bars of each group in close proximity to each other and in the same core-slot, and in order to properly connect the bars, so as to make the windings complete, I spread the ends of the bars of each group apart, and thus provide sufficient space for attaching the end-connectors and at the same time insure a sufficient degree of separation for the connectors to provide proper ventilation. Since my presentinvention is not dependent upon any specific arrangement of circuits, I have shown only a portion of the windings, it being understood that the arrangement of the bar-conductors and end-connectors may be such as to provide a winding for any practical number of phases of current and magnetic poles.

The core 1, to which the windings are to be applied, is provided with as many slots 2 as there are groups of bars, and these slots are preferably nearly closed,as ind icated in Fig. 2.

The bars 3 are made of dilferent lengths to correspond to the arrangement of end-connectors 4 and to the number of phases of current to be generated and the ratio between the number of magnetic poles and the number of core-slots. Each bar 3 is covered with insulation 5, of suitable material and thickness,except at its ends,this insulation 5 being, however, comparatively thin in order that space may be economized, this being permissible by reason of the fact that the bars are so connected in circuit as to provide a minimum difierence of potential between those in each group. The number of bars in a group will obviously depend upon the arrangement of circuits; but, as here shown, three bars are arranged side by side and provided with a cell or sheath 6, of suitable material and suitablethickness. Thisheavyinsulating-sheath 6 is of such length as to project beyond the ends of the core and may be tapered at its ends, as indicated at 7.

In order that the end-connectors t may be suitably arranged and connected to appropriate bars 3, the ends of the bars are separated by bending the two outer ones away from the middle bar, as is clearly indicated in Figs. 1 and 4. The end-connectors are then attached to these separated ends by means of solder, and, if necessary, also by rivet-s or bolts.

I have shown each end-connector as made of two parallel lengths of strap-copper riveted together, the ends being separated, so as to embrace the ends of the bars 3. This particular construction of end-connectors and the attachment thereof to the conductor-bars m ay obviously be modified, however, if desired.

A winding constructed and arranged as shown and described is Well adapted as regards insulation and ventilation for high-potential machines, and while not limited in this respect this particular arrangement would probably be found unnecessary in connection with smaller machines and relatively low potentials.

I claim as my invention l. A bar-Winding for electrical machines the bars of which are arranged in groups in the core-slots, the bars in each group being spread apart at their ends and connected to other bars of the Winding by suitable condoctors.

2. The combination with a slotted core, of a winding comprising a plurality of groups of bars and end-connectors, the bars in the several groups being located in close proximity in the core-slots and being spread apart at their ends for attachment to the connectors.

3. In an electrical machine,the combination with a slotted core, of a winding comprising a set of groups of bars and sets of connectors for the ends of the bars,the bars of each group being located in close proximity to each other and being individually and collectively insulated and having their ends spread apart for attachment of the end-connectors.

4. In an electrical machine,the combination with a slotted core, of a winding comprising a set of groups of bars so disposed that there is a minimum difference of potential between bars in the same core-slot, and sets of connectors for the ends of the bars, said ends being spread apart for attachment of the connectors thereto.

In testimony whereof I have hereunto sub scribed my name this 20th day of April, 1901.

BENJ. G. LAMHE.

\V itn esses:

WEsLEY G. CARR, BIRNEY IIINEs.

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