US1422584A - Electric generator - Google Patents

Description

.L. 1; LE PONTOIS, ,DECD.

A- LE PONTOIS, ADMINIS TRATRIX.

- ELECTRIC GENERATOR. APPLICATION FILED MAILZB, I917- Patented July 11, 1922.

3 SHEETS-SHEET I.

' fnvenio v J/ 7 g ,6 M

L. J. LE PONTOIS, DECD.

A. LE PONTOIS, ADMINISTRATRIX- ELECTRIC GENERATOR. APPLICATION FILED mmza, 1917.

Patented July 11, 1922. I

3 SHEETS-SHEET 2- Afbrrzqq.

L. 1. LE PONTO'IS, DECD.

A. LE PONTOIS. ADMINISTRATRIX.

ELECTRIC GENERATOR.

APPLICATION FILED MAR.28, 1917.

1,422,58 v V PatentedJuly 11,1922.

3 SHEETS'-SHEET 3- UNITED STATES AT OFFICE LEON J1 LE EONTOIS, or LAxmvoon; 0310; mm LE PONTOIS, ADMINISTRATRIX or SAID LEON J; LE ronrois, DECEASED, Assicnoa'ro THE IE-EAGLE COMPANY,- or CLEVELAND; OHIO, e. CORPORATION or OHIO. p y a nnno'rnio GENERATOR.

T 0 aZZ w/lo m it may concern Be it known that I, LEON J. Lu Ponrois, a citizen of the Republicof France, residing at Lakewood, in the county of Cuyahoga and State of Ohio, have inventedcertain new and useful Improvements in Electric Generators of which the following is a specification; reference beinghad therein to the accompanyingdrawing.

This invention relates to improvements in electric generators and more particularly to inductor alternators especially adapted for ignition purposes in connection with internal combustion engines.

The general object of the invention is the provision of apparatus of the character re ferred to highly eflicient and reliable in operation and characterized by simplicity and ruggedness of construction and low cost of production. y

The expedients which I have devised to .these ends will readily be understood from the following description in which I set forth, in connection with the accompanying drawingggs a preferred embodiment of the invention.

In the drawings Figure 1 is a central vertical longitudinal section of an electric generator embodying my invention; c

Fig. 2 is a fragmentary section through one of the distributor segments;

Fig. 3 is a section on the line a a of Fig.

.1; i is a section on the ln olten line 7)?1 of Fig. 1;

Fig 5 is a detail VlOW of one of the distributor parts.

Pig. (5 is a diagrammatic View of the generatii h generator may be used.

teferring in detail to the construction illustrated, 1 indicates as an entirety a rectangular frame structure. This structure preferably comprises a combined base and pole piece of soft iron having a polar face 2*, anupper pole piece 3 of soft iron, and end plates 4L and F of non-magnetic material. The pole pieces 2 and 3 and the end plates i and 5 are rigidly united by screws 6 and dowel pins 7. The pole piece 3, which is preferably cored out as indicated to avoid superfluous metal, has laminated pole ex- Specification of Letters Iatcnt.

; wiring; and a circuit in which the PatentedJuly 1 1,1922.

Application filed March 28, 1917. SerialNo. 158,094.

tensions 8 and 9 with polar facesB and 9,

respectively. Thesepole extensions are pref eraoly formed by a series of soft iron laininee 10 which are rigidly united by rivets ii. The pole piece 3 is formed with dependng undercut flanges or extensions 3 and the laminae 10 are correspondingly notched fto enter between said flanges with a driven fit and form a tlght and rigid dove-tailed latter section isjmade up of a series of soft iron laminae l l keyed upon the shaft and rigidly held between end plates and. 16,"

the plate lfi'bearing against a shoulder on the shaft 18 while the plate 16 is secured] in position by a pin 17. The rotor is operatively mounted in antifriction bearings 18' and 1.9"which are mounted respectivelyin the end plates 4' and 5. The outer ball race of the bearing 18 bears against a shoulder l of the end plate to take endthrust in one direction while the outer ball'race of the bearing 19 bears against a threaded disk 20 which The takes thrust in the opposite direction. The

disk 20 also serves to close the bearing 19 and prevent the escapeof lubricant outwardi The screws 6 and doxvel pi s 7 hold the end plates 4|; and 5 and the pole pieces? and 3 rigidly in accurately lined relationso that the machining of the end plates and of the polar faces to secure the accurate alignment of the bearings l8and 19 with each other and with the polar faces, is readily accomplished. I I 'Onthe opposite sides of the frame structure 1 are arranged permanent magnets 21, with their upper ends in consequent pole relation with the pole piece?) and their lower ends in consequent pole relation with the pole piece 2. The magnets may be secured to the pole pieces; 2 and 3 in any Thesesuitable manner, as by screws 22. magnets-21 are preferably plain straight bar magnets. The number of magnets can be varied but the construction shown contemplates four magnets, two on each sideof the frame I, the combined width of two magnets being equal to the length of the pole pieces 2 and 3 so that when the magnets have been attached to the pole pieces they serve, in connection with the frame structure 1, to completely enclose the interior parts of the generator. At the same time said magnets are in no sense a part of the supporting frame structure 1 which is self contained and stands alone on its own bottom independently of the magnets 21.

On the pole extension 8 is mounted a generating coil 23 comprising an innner section 23 of relatively coarse wire and an outer section 23 of relatively fine wire, see Fig. 6. These windings may, for convenience, be referred to as the primary and secondary windings respectively. One terminal of the primary winding 23 may be connected to ground while the other terminal ol. said winding is connected with a breaker mechanism for opening and closing the primary circuit.

The said breaker mechanism comprises parts as follows: 25 is a cam on the rotor shaft 13 and 26 is a cam lever pivotally mounted at one end on a stud 27 and formed intermediate its ends with a block 26" ar ranged to engage the cam surfaces of the cam 25. At its :tree end the arm 26 carries an electrode 28 arranged to engage an electrode 29 adjustably mounted on one 01"- the outwardly turned ends of the arcuate supporting plate 30 which in turn is riveted to but electrically insulated from the annular plate 31. The other outwardly turned end of plate carries a binding post 30 for an insulated conductor leading to one of the terminals of the primary winding 23. The plate 31 is secured by screws 31 to the end plate 5 of the main frame. The lever arm 26 is secured in position on the pivot stud 27 by means of a clip 32 and said arm is yieldingly pressed toward the cam by the torsion spring 38. When the cam 25 turns with the rotor the electrode 28 on the lever arm 26 is moved. into and out of engagement with the fixed electrode 29 to close and open the primary circuit. The circuit closing and opening mechanism is preferably enclosed by a cap or cover 34 secured in position by clip The circuit of the fine wire winding of the generator coil is controlled by suitable distributor mechanism. In the preferred form of construction illustrated, the end plate 5 is recessed to receive a driving pinion 86 mounted on the rotor shaft 13 and a gear 37 driven by the pinion 36 and fixedly mounted on the inner end of a hollow shaft 38 which is rotatably mounted in a bean ing 39 formed in the end plate 5. The outer end of shaft 38 is circumferentially grooved to receive a clip ring 40 which secures the shaft against displacement. Fixedly mounted in the hollow shaft 38 is an insulation block ll which comprises a hub section 41. and

a radial arnii section ll". In the axis of the hub section 4U. is arranged a conductor which is conducted at its inner end with a tubular socket in which is mounted a brush n pressed by spring 45 into engagement with the terminal plate 46 of the fine wire winding 23 01 the generating coil. At is inner end the conducton 42 is electric ally connected to the inner end of a radial conductor plate 47, which, at its outer end. is connected to the tubular socket .1-8 in the outer end of the insulation arm l-l In this socket is mounted a brush 49 which is pressed yieldingly outward by a spring 50. 51 is a combined distributor blocl: and cover formed of suitable insulating material and shaped to lit closely an annular flange .5 of the end plate The distrilnitor block carries a suitable number of contact segments 52 which are engaged in the well known manner by the moving brush 49 of the distributor. In the present case there are four oi? the contact segments and each may be suitably ,;onnccted with a coin ductor leading to one of the s .)arlc plugs of an engine in the well lcuown manner. i

The distributor cover 51 may he cured in position in any suitable manner, as by the lingers or clips 53 which are pivot-ally connected at 54; to the face plate 5 and have resilient hook-shape LS that engage suitable notches (not shown) in the front face oi the block 51.

3 is a conductor plate secured to and grounded on the pole piece 3 so that it is die:- posed adjacent and spaced from the terminal plate 1-6 of the generating coil to provide a spark gap. 7

is a concenser oil any suitable construe 'tion mounted on the pole cXtension 9. being secured thereto in any si'iitahle manner.

Pei rring to the diagram oi the electrical connections in Fig re 6. it will he observed that the primary winding 23" of the generating coil has one of its terminals crninectcd to ground through a switch 57 while 11:4 other terminal is connectml to the stationary electrode 25) of the circuit closing and open-- f f llltEfillllillf illl. The movable electrode 12b is connected to ground (throngh the "Frannoi the machine) and the condenser so is connected, in the usual manner. in parallel with the electrodes 28 and 29. The secondary winding 23 of the gene ating coil has one of its terminals connected to one of the terminals of the primary winding: 23 while its outer terminal is connected. with the moving element of the distributor mechanism. At 58 i. show a battery one terminal of which is grounded and the other of which is arranged to be connected. when desired. through switch 57 with the primary winding of too generating coil.

The operation oi the generator will be readily understood by those skilled in the extension 8 which, in effect, constitutes the;

core of thegeneratingwinding. As. the rotation continues the forward edge: of the upper side of the flux distributing section of the rotor comes adjacent the pole extension 9 and a portion of the magnetic flux. then begins to flow through the latter extension, the flux through the generating coil being correspondingly diminished. Approximately at the point when the decrease of flux through the generating coil reaches a maximum, the breaker cam 25 acts to break the primary circuit of thecoil whereupon a high tension current is generated in the secondarv winding of the coil, said current being reinforced by the continued decrease of the magnetic flux through the coil incident to the continued rotation of the rotor. As said rotation continues, the lower side of the flux distributing section of the rotor leaves the polar face of the pole piece 2 and its forward edge comes adjacent the pole extension 8 while the other side of the fluxclistributing section in turn comes adjacent the polar face of the pole piece 2. In this way the magnetic flux is again. established through. the pole extension 8, and the operation of the circuit breaker is so, timed that the primary circuit remains open until the increase of flux through the pole extension 8 has ceased whereupon the primary circuit is again closed through the breaker electrodes 28 and 29.- Then with continued rotation the cycle of operations is repeated. The distributing mechanism is of course synchroe nixed with the breaker; and rotor so that the;

distributor brush 4-9 is in contact with one of the segments 52 when the high tension current is induced in the secondary winding.

The generator, as illustrated is intended for use with a four-cylinder internal combustion engine, being adaptechwhen the generator is driven at crank shaft speed, to give two sparks per revolution. It will be understood that any suitable gearing may be provided for driving the generator from the engine and, if desired, use may be made of one of the well known forms of coupling devices adapted, either automatically or under manual control, to advance and retard the spark by efiecting an angular advance or retardation of the rotor in relation to the crank shaft of the engine.

When the generator is used for starting an engine, the battery can be employed'if desired tov energize the prlmary winding,

care being taken that. the battery is connected in circuit so as not to de-energizethe'permanent magnet. a

I have explained that the primary circuit is. never closed while the. magnetic, flux through the generating coil is increasing but that the current induced in the primary winding is. always due to decrease 111:: through said winding; and inasmuch as the generating 'windings are fixed inrelation to the permanent magnets, it follows that the magneto-motiveforce generated by the current induced in the primary winding, and also-by the current induced in the secondary winding by the interruption of theprimary circuit, always acts with the n1agneto-mo tive-force of the permanent magnets and not against it. Hence, by reason of this constantelectro-magnetic relationship of the path of least reluctance between the poles of the permanent magnets and through the generating,windings, the permanent magnets are never, subjected to demagnetizing action in theoperation of the generator.

This constant electro-magnetic relationship which characterizes my improved generator not only tends to maintain the maximum efficiency and capacity of the generator, but makes possible also other notable advantages. Thus, by reason of this characteristic of: the ma netic circuit, I have found it possible to employ material for the permanent magnets having a relatively low coercive'force'and to use magnets ofa length not exceeding the'heightof ignition current generators complying with standardization requirements. In other words, I am enabled to use a relatively cheap material for the permanent magnets and to make themin straight bar form, wlth a minlmum amount of fabrication so that their cost of productionris exceedingly low.

In addition, the form of magnet thus made possible in turn gives rise to advantages of great practical importance. That is to say, these straight bar magnets lend them selves, admirably to use in connection with a main:supporting frame such as has been (1 escribed; In this fraln e the lower pole pi ecc and base, the upper pole piece and the two end plates, all rigidly connected, form a structure closed on four sides, and the plain bar magnets, of a length not exceeding the height of the supportingframe, are readily applied bysimple attaching means, so as to entirely close the chamber within the frame structure so that the interior workng parts are provided witha dust and water a tight casing. Furthermore, with the straight bar magnets assembled in this .manner, it is possible to machine the bottom pole piece to fit and besecured to a standard magneto support. v And ,asthe straight bar magnets support none of theother parts of the'mechanism, they can at any time be readily re moved to expose the interior parts for in spection or repair.

I have already referred to the constant electro-magnetic relationship of the fixed lath between the poles of the permanent magnets as a factor in the maintenance of the elficiency and capacity of the generator. It is to be noted further in this connection that the magnetic flux through the pole pieces and polar projections, including the polar projection 8 which constitutes the core of the generating coil, is unidirectional so that heat losses in these iron parts are minimized and the efiiciency correspondingly increased.

The simplicity of the rotor and its com paratively light weight, besides making alignment easy, puts very little wear on the bearings and make possible exceedingly high speed operation.

Since the generating coil is stationary, it can be grounded on the stator so that no current passes through the bearings and, also, much more space is available for the generating coil and the condenser than would be available if they were mounted on the rotor, so that ample insulation may be used without exceeding the standard magneto height.

A distributor mechanism constructed as herein set forth can be made absolutely water tight, and, at the same time, the interior parts can be exposed by simply swinging back the hinged fingers or clips 53 and removing the block and cover 51.

The breaker mechanism is readily exposed for repair or adjustment by simply swing ing aside the clip; 35 and removing the cover 34.

lVhile I preferably prevent a demagnetizing effect upon the straight bar magnets by controlling the circuit of the generating winding as above set forth, the invention is not to be understood as limited to that precise manner of circuit control, for I believe that I am the first to provide an. ignition generator having pole pieces, end. plates, straight bar magnets, generating Winding and rotor, as above described, and means for controlling the circuit through the generating winding adapted, when the rotor driven at a uniform speed, to open or close the circuit in such manner that the net effect on the magnets of the reaction of the winding is a magnetizing effect. In other words it is to be understood that the advantages of my invention can be secured in a substantial measure even if the magneto-motive force incident to the reaction of the generating winding is opposed to the magneto-motive force of the magnets during a part of the cycle of operations providing that during other parts of said cycle there is a superior magnetomotive force incident to the winding reaction in the same direction as the To those skilled in the art it will be apparent that I have provided a generator with avery small number of parts and also that the individual parts are exceedingly simple and. substantial and capable of production with precision by economic methods. It will also be seen that the structure is easily assembled.

It will be understood that the structure which has been particularly described may be varied in various respects without departing from the invention and that said structure has been set forth in detail for purposes of explanation and. illustration and is not to be construed in a limiting sense.

In so far as the subject-matter herein.- after claimed is common with the disclosure in my earlier applications, Serial I O. 596,117, filed December 7, 19M), and Serial. No. 627,927, .liled l\ilay .18, .1911, I hereby elect to treat this application as a continuation of the said. earlier ones.

vl hat I claim is:

1. In an ignition. current generator, the combination of a bottom pole piece of cast iron formed on its top side with a polar surface and on its bottom side formed to rest upon and be secured to a suitable support for the generator, a top pole piece comprising a cast iron block and a plurality of bifurcated laminae secured thereto and forming depending polar projections with polar surfaces at their lower ends opposite the polar surface of the bottom pole piece, nonmagnetic end plates rigidly attached to the said pole pieces and forming therewith a rigid supporting frame, permanent magnets in the form of straight bars disposed on opposi'te sides of said supporting frame with their north pole ends abutting one pole piece and. their south pole ends abutting; the other pole piece, a generating winding in inductive relation to one of said polar projections, and an unwound :iiuluctm' rotor operably mounted in said end. plates and shaped. and correlated to said polar surfaces of the poles alternately to establish a flux path through said winding and then a path outside of said winding.

2. In an ignition current generator, the combination of a bottom pole piece of case iron formed on its top side with a polar surface and on its bottom side formed to rest upon and be secured to a suitable support for the generator, a top pole piece comprising a cast iron. block and a plurality of bifurcated laminae secu red thereto and forming depending polar projections with polar surfaces attheir lower ends opposite the polar surface of the bottom pole piece, nonmagnetic end plates rigidly attached to opposite sides of the said pole pieces in planes substantially parallel with the laminae of the said depending polar projections and forming with said polar pieces a rigid supporting frame, permanent magnets in the form of straight bars disposed on opposite sides of said supporting frame with their north pole ends abutting one pole piece and their south winding.

3. In an ignition current generator, the" combination of a bottom pole piece of cast iron formed on its top side with a polar surface and on its bottom side formed to rest upon and be secured to a suitable support for the generator, a top pole piece comprising a cast iron block and a plurality of bifurcated laminae rigidly secured to the under side of said block by a forced fit dove-tail connection "and forming depending polar projections with polar surfaces at their lower ends opposite the polar surface of the bottom pole piece, non-magnetic end plates rigidly secured to the pole pieces in planes parallel to the said laminae and forming with the pole pieces a rigid supporting frame, permanent magnets in the form of straight bars disposed on opposite sides of said supporting frame with their north pole ends abutting one pole piece and their south pole ends abutting the other pole piece, a generating Winding in inductive relation to one of said polar projections andan unwound inductor rotor operablymounted in said end plates and shaped and correlated to.

said polar surfaces of the poles alternately to establish a flux path through said winding and then a path outside of saidwinding'.

In testimony whereof, I affix my signature.

LEON J. LE PONTOIS.

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