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Publication numberUS1314132 A
Publication typeGrant
Publication dateAug 26, 1919
Filing dateJul 31, 1918
Publication numberUS 1314132 A, US 1314132A, US-A-1314132, US1314132 A, US1314132A
InventorsFarnum F. Dorsey
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Farnum f
US 1314132 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)




1,3 1 4:, 1 32 Patehted Aug. 26, 1919.



Specification of Letters Patent. 1 Patented Aug. 26, 1919..

Application filed July 31, 1918. Serial No. 247,611.

To all whom it may concern:

Bt it known that'I, FARNUM F. 'Donsnr,

v aacitizen of the United States, residing at Rochester, N. Y., in'the county of Monroeland. State of New York, have invented certain new and useful Improvements in Field- Magnets; and I do hereby declare the following to be a full, clear, and exact descrip- --tion of the invention, such as will enable others skilled in the art to which it.appe r- .tains to make and'use the same.

This invention relates to a field inagnet.

I for use in electric motors'or generators, or

other apparatus. Y In dynamo-electric machines of the ironclad type,*in which the field-poles are in the form of inward projections from a mg or shell of iron, it is common to use windings, upon the polar projections, comprising form-wound coils which are placed, already wound, on the'piojections. To combine efliciency with economy of material, the polar projections should have comparatively slender necks and-wide faces, but this form in ent' invention.

troduces difliculty in applying the coils to the projections, unless the' projections are made separable, in whole or in part, from the ring ,or shell of the field-magnet.

.The object of the present invention is to produce a magnet, of the type in question, in which'the polar pro ections are connected integrally, without any break in the magobliquely through the polar projections, this.

mode of division facilitatingthe application of the coils, ashereinafter eitplained, without introducing any break or air-gap into the magnetic circuit. I

In the accompanying drawings Figure 1 is a side-elevation, partly in section, of a two-pole field-magnet embodying "the prestohug the parts 6 closely.

I Fig. 2*is a side-elevation showing the'manner in. which: the parts of the magnet are assembled. Fig. 3 is a sideelevation ofa four-pole magnet.

In Figs. 1 and 2 the inventionis shown as embodied in a bi -polar'field-magnet. The

core of the magnetcomprises two'similar' sections which, together, constitute the usual circular yoke, with inwardly directed polar .proj ections. .Each section comprises a bodyportion5, at the ends of which are inward projections 6 and 7, terminating in horns 8 and 9, respectively. The parts 6 and 7 of. the two sectlons meet on parallel planes :10, so. as to form two comparatively nar row necks on which the coils 11 are mounted in the usual manner. v

The planes of cleavage .10, since they pass approximately lengthwise: through the polar projections, do not interrupt the continuity of the paths of the magnetic lines of force,

but they permit the coils, already formed, to be placed upon the necks, in the manner shown in Fig. 2. Itwill be apparent that if the coils be passed over the-horns 9 and seated against the parts 7, asshown, the two core-members may then he slid together, by relative movement .along their meeting faces,- so as to pass the horns 8' through the "coils, and the completion of this movement causes the coils to swing intoposition The two core-member's may be supported in cooperative relation in any convenient way: In Fig. l they are shown as embraced by .a cylindrical shell 'or housing 13, which be important, the outer corners of the sectioris may be roundedofi as. shown by the dotted lines 12 'in Fig. 1, without any sub- .stantialsacrifice of efiiciency. The sections may also be made, either solid or laminated,

as may be most convenient.

- The invention is applicable to multi-polar field-magnets as wellas to bi-polar. Fig.3

shows a four-pole magnet, which differs from that of Fig. 1' only .in that the body portion '14; of each section 'an'arc of on1y 90.

maybe of magnetic or non-magnetic ma- .terial. If economy of material and'weight extends through The invention claimed is: obliquely through opposite polar projec- A field-magnet comprising an annular tions, into a, plurality 'of sections, each secbody and inwardly directed polar projectioncomprising a yoke or body-portion and, 10

'tions,- each projection having a neck and at each end, approximately half of'a, polar 5 horns atthe inner end of the neck;- the projection.

magnet; bein characterized by the fact that t it 1s div'ide on parallel planes passing FARNUM F. DORSEY.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2453358 *Mar 7, 1945Nov 9, 1948Alex BerteaElectric motor
US2500191 *Nov 19, 1945Mar 14, 1950Lee RoyalCompensated electric motor
US2501222 *May 3, 1946Mar 21, 1950Bretislav HyblerAlternating current generator
US2764802 *Jul 17, 1953Oct 2, 1956Gen ElectricMethod of assembling a field coil on a stator
US3087080 *Feb 6, 1961Apr 23, 1963Globe Ind IncElectric motor
US3440460 *Aug 30, 1967Apr 22, 1969Universal Electric CoLaminated motor stator with formed coils and shaded poles and method of making
US4311934 *Feb 26, 1980Jan 19, 1982Gebruder Junghans GmbhOff set stator laminations for small rotary transducers
US6452302 *Sep 21, 1999Sep 17, 2002Hitachi, Ltd.Rotary electric machine and electric vehicle using the same
US6661147 *Mar 7, 2002Dec 9, 2003Hitachi, Ltd.Electric vehicle and rotary electric machine having a divided rotor core
US7078843Sep 3, 2004Jul 18, 2006Black & Decker Inc.Field assemblies and methods of making same
US7146706Sep 3, 2004Dec 12, 2006Black & Decker Inc.Method of making an electric motor
US7205696Feb 18, 2005Apr 17, 2007Black & Decker Inc.Field assemblies having pole pieces with ends that decrease in width, and methods of making same
US7211920Feb 18, 2005May 1, 2007Black & Decker Inc.Field assemblies having pole pieces with axial lengths less than an axial length of a back iron portion and methods of making same
US7233091Sep 3, 2004Jun 19, 2007Black & Decker Inc.Electric motor with field assemblies having core pieces with mating features
US7528520Oct 4, 2006May 5, 2009Black & Decker Inc.Electric motor having a field assembly with slot insulation
US8207647Jan 14, 2011Jun 26, 2012Black & Decker Inc.Power tools with motor having a multi-piece stator
US8558420May 22, 2012Oct 15, 2013Black & Decker Inc.Power tool with motor having a multi-piece stator
US20070024151 *Oct 4, 2006Feb 1, 2007Du Hung TElectric motor having a field assembly with slot insulation
DE19507264A1 *Mar 3, 1995Sep 12, 1996Fein C & EStänder für eine elektrische Außenpolmaschine
U.S. Classification310/216.31, 310/216.9
Cooperative ClassificationH02K1/141