US1279750A - Magneto-electric generator. - Google Patents

Description

a. A. OGLESBY.

MAGNETO ELECTRIC GENERATOR.

APPLICATION FILED FEB. I7. I9|6.

1,279,750. Patented spt. 24,1918.

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@trouw L4 H. A. OGLESBY.

MAGNETO ELECTRIC GENERAToR.

APPLICATION FILED FEB. l?. i916.

1 ,279,750. l Patented Sept. 24, 1918.

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attorno# UNITED sTATEs PATENT oEEioE.

RICHARD A. OGLESBY, OF SOUTH BEND, INDIANA, ASSIGNOR TO QUICK ACTION IGNITION COMPANY, OF SOUTH BEND, INDIANA, A CORPORATION OF INDIANA.

MAG-NETO-ELECTRIC GENERATOR.

Specification of Letters Patent. Patnted Sept, 24, 1918 Application led February 17, 1916. Serial No. 78,854.

To all whom t may concern Be it known that I, RICHARD A. OGLESBY, a citizen of the United States, residing at South Bendin the county of St. Joseph and State of Indiana, have invented certain new and useful Improvements in Magneto-Electric Generators, of which the following is a specification.

My invention relates to improvements in magneto electric generators and it appertains more especially to the specific features p pointed out in the annexed claims.

The purpose of my invention is to provide a simple, compact and eiiic-ient ignition device for single or multi-cylinder internal combustion engines; that will admit of a multiplicity of independent coil units; that through the momentary bridging of the lield magnet circumferential air gap by a single armature pole in advance of an adjacent coil there is a sudden forced building up of a dense magnetic flux through the armature coil that will operate equally Wellin either direction of rotation of the iield magnet and which is a continuation in part of the subject matter disclosed in my copending application Ser. No. 10,005, filed Feb. 23, 1915,"

issued April 16, 1918, No. 1,262,692.

With these and other ends in View I illustrate such instances of adaptation in the accompanying drawings as will disclose the broad features without limiting myself to the specific details shown.

Figure 1 is a partial diagrammatic elevation of a single coil unit with the usual accessories of condenser, breaker and cam adaptedto high tension service. For low tension service the condenser and breaker are omitted and a primary winding is used instead.

F 2 is a similar View to Fig. l showing the field magnet shifted so as to subject the armature core and coil to the maximum flux.

Figf shows the field magnet further advanced than in Fig. 2 with the trailing armature pole within the circumferential air gap.

Fig. 4 is an elevation of an armature and magnet with short pole pieces.

Fig. 5 represents a tracing'from an oscillogram of the performance of aunit coil with an unbridging armature pole shown in Fig. 4.

under the progressive advancement of the iield magnet.

Fig. 7 is a diagrammatic View of a group of four generating units.

Fig. 8 is a simlar view of siX generating units.

F 9 is a sectional elevation of Fig. 7. Fig. 10 is an elevation showing the grouping of separate generating units side by side to be acted on by a single field magnet.

Fig. 1'1 is an elevation in section of Fig. 10.

In carrying out my invention I provide a suitable circular permanent magnet 1 secured to a holder or flanged disk support' 12. The disk has a hub 13 that is fastened to shaft 14 which may be a continuation of an engine shaft or it may be separately driven as the eXigencies of various uses demand. A circular polar air gap 6 is formed between the ends of the magnet and highly permeable pole pieces 2 are placed adjacent so as to concentrate the magnetic flux at such point.

The armature may comprise a single coil unit or a multiplicity of units that have cores 4, and pole heads 3 suitably secured to a disk 16 which has a hub 15 resting on bearing support 30. It does not rotate with the shaft but it may be rocked to and fro by means of handle 25 so as to advance or retard the spark supplied to the engine. The disk 16 is held against rotation with the shaft in any suitable manner.

A core 4 and heads 3 with a winding therebetween-Whether a primary 5 alone or a secondary 33 combined therewith being immaterial-constitutes a generating unit which may be multiplied in any suitable manner, in tandem as shown in Figs. 7 and 8 or side by side as shown in Figs. 10 and l1 or as combinations of these.

The armature pole heads 3 are cut under at 9 to secure an increase of winding space which at the same time admits of a reduction in the distance between the ends 35 and 36 so as to span pole pieces 2 and also permit a head 3 to reach across space 6 thus securing the much desired momentary short circuiting of the flux before it is swept across the armature coils. By omitting the projection from heads 3 the relation of parts shown in Fig. 4 would be secured with a corresponding loss in efficiency. Thus by having the projections on one side only of the core 4 so as to extend toward each other special advantages are ained. The end faces 10 may be formed raial or tangential with respect to the center according to the requirements of the various number of units that are to be combined on a single holder 16 and its allowable working diameter. The outer face of the heads 3 lying inside of the radial air gap between such face and the inner face of the pole pieces 2 of the field magnet is of such a length 8 Fig. 1 as to completely span the polar air gap 6 and the pole pieces 2 are long enough as shown by arc 7 to practically fill the space 11 between the adjacent edges of heads 3 Fig. 3.

This arrangement of parts brings about a unique sequence of results which may be readily followed by starting with the relation of parts shown in Fig. I in which the space 8 is found across the gap 6 when the main fiux will pass from one pole piece 2 to the other across leading in head 3, momeny tarily short circuiting the slight leakage indicated at A Fig. 6 through the core 4L and coil 5. As soon as pole piece end 34 leaves the end 3 5 and ends 36 and 37 pass each other, there is an in-rusli of fiuX that sweeps across the coil with great suddenness, producing the effect shown at B Fig. 6. As magnet 1 with its gap 6 and pole pieces 2 continues to move in the direction of the arrow, edges 38 and 34 will soon approach edges 35 and 36 as shown in Fig. 2, further movement of magnet 1 causes the edges to separate` 38 moving toward 36 and 39 to- Ward 35 so as to gradually weaken the fiux and produce the negative impulse shown at C Fig. 6. When edges 39, 35 and 38, 36 pass each other the flux tlireadingcore 4: will gradually drop to Zero and the spanning of the air gap 6 by space 8 formed by leadin out head 3 will have no further practical e fect on the coil while the field magnet revolves in the direction shown.

The short peaks a land d of Fig. 6 are caused by a momentary leakage through the core before andl after the main inductive effects B and C have taken place.

In contrast to these results oscillogram,

Fig. 5 is shown. This has points e, f, g and it respectively comparable with a, B, C and d of Fig. 6. This result is attained by using short pole pieces 32 secured to the field magnet 1 at such positions as to admit of practically the saine coil space as employed in Fig. 1, however using short armature heads 17 having arcs 18 comparable with pole pieces 32. A comparison of Figs. 5 and 6 shows such a marked increase of result Where the gap 6 is short circuited immediately preceding the full flux saturation of core 4 that without such provision would be unattainable. l

The flux swept across the coilis unidirectional and the movement of the magnet may opposite sign in coil 5. The small extra peaks infthe curve of Fig. 5 are produced at other points of momentary leakage. The field magnet 1 may have a counter balance 31 placed in the air gap 6 Where it is held in any suitable manner. induced in primary coil 5 are to be used for high tension service a secondary winding 33 is used, with suitable service connection. In such an adaptation one of the primary coil leads 20 is connected to a contact 23 which is insulated from disk 16. The other end 28 is connected to ground. The contact 23 is broken by spring 21 being drawn away when shoe 22 rides on to cam 19. The spring and shoe are secured to a common grounded hub and have bearing on stud 20 and they are held in position by spring 24. These features may be carried out in many -various ways. In such installations a condenser 26 is connected by lead 27 to contact 23 and by another `lead to ground.

' The primary circuits of separate coils may be led to a mechanically synchronized distributer and a single breaker used if desired, the secondaries supplying separate spark plugs. In the case of a low tension adaptation the current would be taken to a mechanical breaker usually found in connection with, wiping contacts, etc., in engine cylinders.

When thel coils are placed in tandem as shown in Figs. 7 and 8 the space between them may be used for condensers 26 if they are required. The armature heads of one unit are separated from those of another When the currents 4 entirely independent of each other magnet-v ically and electrically.

If the units are placed side by side as shown in Figs. 10 and 11 they may be staggered with respect to each other, one half being on one side of a disk 16 and the other half on the other side as shown in Fig. 10 or a disk 16 may be -used for each set, the two being suitably secured to each other as shown in Fig. 11 so that all are simultaneously adJusted for spark control.

The outstanding feature of my invention consists in the production of unique results through the medium of a short air .gap active at a large distance from the center of rotation; the entire bridging of the air gap in ladvance of coil linduction; suddenly sweeping a unidirectional fiux across the coil under a shorter time constant than is possible when the fiux is reversed; and in sub- ]ecting more turns of the coil to induction due to an increased coil space provided under proJecting heads without sacrificing the bridging effect.

A- unidirectional flux is not subject to the lagging effect that a reversal of flux encounters, hence other things being equal, a more sudden and intense peak is produced which will meet the demands of actual practice at extremely slow speeds. Shuttle type armatures working under flux reversing c onditions, must be operated at relative high speeds to produce the initial sparking current and are limited to slow flux changes due to their air gaps occupying a large part of each revolution which in contrast to the very sudden flux change secured in magnetos of the non-reversal type instanced herein is notable, being largely due to the very small part of each revolution in which the entire fiux change takes place, the increased radius at which the effect is produced and the enlarged coil space available under the projecting armature heads without lengthening the field air gap.

The effect produced by having the armature heads on opposite sides of the center of rotation, as is common in shuttle-type armatures, is the same whether the filed or the armature is rotated-in either case an alternating current is induced through a complete reversal of the flux. I

When both armature heads of a given coil are on the same side of the center of rotation as ins-tanced in the drawings an alternating current is produced through an oncoming and outgoing non-reversing flux regardless whetherthe armature or the field magnet is rotated. Thus two distinct types of magnetos are produced the variations of each type being comparable with each other but the results and conditions applicable to one type are not directly comparable with those of the other type. For this reason a movable armature or field magnet under non-reversing {iux induction produces results of a different order from those secured by a moving armature or field under flux reversing conditions.

Without the use of the overhanging heads a longer air gap must be used at the same coil space which means a slower flux change per each revolution and a lowered potential, or a reduced coil space ata shorter air gap giving practically the same results due to a maller number of turnsbeing swept by the llX.

As soon as the heads overhanga much shorter air gap can be used which at once results in a more rapid flux variation for each revolution-which in itself induces a higher potential and in addition an increase in coil turns that supplement the more rapid flux changes, thereby securing eXtraordinary practical results at extremely slow speeds. An attainment of no small import when the exacting demands of strenuous practical requirements are duly considered. For this and other reasons the use of overhanging armature heads adapted to completely bridge the field air gap and a nonvreversing flux induction with maximum coil space are claimed in their broadest aspect without being limited to specific expedients of construction or adaptations to meet the varying exigencies of actual practice in largely differing industrial applications.

What I claim is l l. A circular permanent magnet having an air gap therein and pole pieces placed on each side of said air gap, an armature coil, a core therein, pole heads projecting therefrom and extending toward each other on one side of the core only and means Afor periodically bridging the field magnets circumferential air gap by both armature poles and core simultaneously and byeither armature pole, singly in alternating sequence through the movement of the field magnet. 2. A series of' independent armature coils, cores therefor, a circularly shaped movable field magnet having a circumferential air gap, pole heads extending from the armature coils and projecting toward each other adapted to singly span the field air gap, means for producing movement of the armature coils and the magnet with respect to each other, whereby independent currents are generated in the separate armatures.

3. A series of armature coils each coil having enlarged heads which project and approach toward each other on one side of the coil, a core within each coil connecting the heads thereof and forming a coil unit, a support for all the coils, a rotatable field magnet having an air gap therein adaptedu tobe successively spanned by the armature heads, means for displacing the coils and magnet with respect to each other whereby the coils will be successively subjected to a unidirectional flux, and current impulses will be produced therein that may be used independently of each other.

4. A magneto comprising an armature having a coil, a core therethrough, enlarged heads connected to the core, said heads projecting toward each other on one side of the core only to provide a lengthened coil space within the projections, a rotatable field magnet of relative large diameter having an air gap of short length formed therein, and pole pieces in contact therewith on each side of said air gap, the ratio of'such pole pieces to the distance between the armature heads and the length of such heads to the air gap being such that the heads and pole that alternative magnetic paths are successively established first through an armature head and immediately thereafter through the armature core whereby impulses of opposite sign are produced in the armature coil without a reversal of the magnetizing flux.

6. A magneto comprising an armature coil, a core therein, enlarged heads at each end of the coil forming a magnetic continuation of the core, projections formed on said heads the Same extending to one side of the core only and extending toward each other to form a lengthened winding space within the projections and a reduced distance between the ends of said projections, a rotating field magnet, means for supporting the armature at one side of the magnet center against rotation, pole pieces for the magnet forming an air gap therebetween of such length as to be first completely bridged by a single armature head and its projection so as to form a momentary magnetic path across this gap of high permeability admitting of a very concentrated flux density that is immediately also followed by a shifting of the magnetic path to include the other armature head each projection and the core whereby an electric current is generated in the armature coil by sweeping a unidirectional fiux across the coil through the movement of the field magnet.

7. A magneto comprising a relatively stationary armature and a rotative field magnet, a support for the armature, a'coil, a core therein, enlarged heads to the core, projections from said heads extending toward each other on one side of the core only, windings on the core between the heads and within the projections, pole pieces on the field magnet forming an lair gap therebetween, the pole pieces being so spaced with respect to eachother that a single armature head and its projection will completely span the air gap and simultaneously present some of the end-turns of the coil winding Within the path of the field air gap flux while a projection is positioned between such turns and the pole pieces.

8. An armature comprising alternative magnetic paths, a coil and a core with its heads that project outward and toward each other constituting one path and a single head the other path, and means for successively shifting a unidirectional flux from one path to the other whereby impulses of opposite sign are produced in the coil Without reversing the direction of the flux.

9. A magneto comprising an armature having a suitable support, a coil, a core and heads to said core supported thereby, and projecting outward and toward each other more on one side of the core laxis than on the other; a circular permanent magnet having an air ga'p therein, circular faces to said, heads of such length so that a single headiwill span the air gap, a pivoted support for the magnet, and means comprising a' shaft secured to the support adapted through the movement of the magnet caused by the rotation of the shaft to sweep a unidirectional flux across thevcoil immediately after a head has spanned the air ap.

10. A magneto, comprising in ependent armatures having cores, coils o n the cores and pole heads secured to a suitable support,

and to the cores, rthe heads having projec-` tions which partly inclose the coils on one side of the core and alsov reduce the air gap between them while the coil space adjacent the projections and the core is increased in length to accommodate a greater `number of turns in the coils, a field magnet having an air gap therein, curved faces formed on the armature heads ofsuch length that a single face will span the air gap, and means for rotatably supporting the magnet to successively sweep a unidirectional flux across vthe armature coils.

pair of curved heads to said coil, the center of such curve being to one side of the coil axis, projections to the heads extending toward each other on that side of the coll removed from the center of curvature of such heads, and a rotating field magnet adapted to move its air gap adjacent the curved heads.

In testimony whereof l aliix my signature in the presence of two witnesses.

RICHARD A. OGLESBY. Witnesses:

A. M. Sonnn'rznn, N. S. AMsTU'rz.

armature including a coil, a core therein, a v

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