US1549119A - Ignition magneto - Google Patents

Ignition magneto Download PDF

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US1549119A
US1549119A US542929A US54292922A US1549119A US 1549119 A US1549119 A US 1549119A US 542929 A US542929 A US 542929A US 54292922 A US54292922 A US 54292922A US 1549119 A US1549119 A US 1549119A
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Prior art keywords
coil
core
rotor
magneto
pole pieces
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US542929A
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William W Hawkins
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Webster Electric Co Inc
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Webster Electric Co Inc
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02KDYNAMO-ELECTRIC MACHINES
    • H02K21/00Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
    • H02K21/26Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with rotating armatures and stationary magnets
    • H02K21/28Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with rotating armatures and stationary magnets with armatures rotating within the magnets
    • H02K21/32Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with rotating armatures and stationary magnets with armatures rotating within the magnets having horse-shoe magnets
    • H02K21/325Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with rotating armatures and stationary magnets with armatures rotating within the magnets having horse-shoe magnets with the axis of the rotating armature perpendicular to the plane of the magnet

Definitions

  • This' invention relates to magnetos of the type which are commonly employed with p ofthe rotor,.permanent magnet poleV piecesl internal combustion engines for ignition purposes.
  • the object' ofthe invention is to provide a magneto of this character which will gen-v erate an exceedingly intense spark' yet will Anot be complicated in its construction and will consist of relatively Vfew parts. l
  • One of the features of the present invention is the arrangement of the transformer core with its ends adjacent to inductor elements carried at Opposite ends of the magneto rotor.
  • Figure 4 is -a section taken substantially on the line 4-4 of Figure 1;
  • Figure 5 is a section taken on the line 5-5 vof Figure 1;
  • ⁇ Figure 6 is a schematic lperspective view and ends-of the transformer ⁇ core, showing thl relativev relations ofthe several parts
  • an y Figure 7 is a diagrammatic illustration of circuit employed with the device.
  • 10 indicates the perma' nent magnets, which are of the usual horse-Z shoe or U-shape,and are mounted side byside so as to be, in eii'ect, a single magnet.
  • the magnets 10 are provided with the usual laminated pole pieces 11 and 12.
  • the magnets 10 and pole pieces 11 and 12, are secured in position by the base portions 13 and 14,
  • cover plate 15 Secured to the remote edges of the magnets -10 andthe base members, in any desired manner, are thel end cover plates 15 and 16.
  • the cover plate 15 is provided with an opening 17 through which projects one end of the rotor shaft 18.
  • Cover plate 15 is also provided with anv annular recess in which is mounted the ball bearing 20.
  • the cover plate, '16 is provided with an y opening 21 through which projects the collar 22 on'thev shaft 18.
  • the plate 16 is provided also with an annular recess 23 within which is'mounted the ball bearing 24 for the opposite end of the shaft 18.
  • the armature 25 are the Agenera-tor coils 26.
  • Coils 26 are arranged in series, and are, in effect, a single coil. Rigidly secured to the shaft 18, 1n any i desired manner, adjacent to the bearings 20 and 24, respectively, are the cylindrical su porting members 27 and 28. ounted wit in the outer periphery of the supporting member 28 are the arcuate laminated in- -ductor-elements 29 and 30.- These inductcr elements are symmetrically positioned on iopposite sides of the support 28, and each extends through an arc of substantially Mounted within .the periphery of the sup ,port 27 is a similar air of laminated induem tor elements 31 an K32, which'..areof sub stantially the same size as those moclated with the support 28, and likewise are symmetrically arranged -at opposlte sides of the support 27.
  • the inductor element 32 1s, however, arranged slightly in advance of the inductor element 30, as shown in Fig. 6.
  • the inductor element 31 isarranged 1n advance ofthe inductor element 29 in the same' way 'that inductor element 32 is advance i of the inductor element 30.
  • the extension 36 has its free end adjacent to the path of the inductor segments 29 and 30, while the free end ofthe extension 37 is adjacent l ⁇ to the path-of the inductorl segments 31 and Extending through the laminations forming the rotor armature 25, atvthe opposite -ends thereof, are the pins 38 and 39.
  • each of the pms 38 and 39 are re.- ceived by openings in the adjacent surfaces ⁇ of the supporting elements 27 and 28, respectively.
  • Spacing sleeves' 40 are mounted about the. ins 38 and 39 between the remote sides of't e armature member 25 'and the su rting members 27- and 28.
  • a housing member 41 ounted aboutthe ⁇ right end of the shaft 18, as seen'in Fig. 1, with its free edges in sliding engagement with the outer surface of the oiset portion 23 of end 16 is a housing member 41.
  • the cover member ⁇ 42 of insulating Inl screw threaded engagementvwith the end of the housing member 41 is the cover member ⁇ 42 of insulating.
  • a post orstandard 43 Projecting outwardly from the base member .13" is a post orstandard 43,
  • the movable interrupter contact arm'45 is pivotally supported on the link 46which 1n turn ismounted in the inwardly projecti'ng,ilange 47 of the housing member 41.
  • the movable contact Aarm 45 is provided .intermediate its ends with the projecting lug v48 of insulating material which may be secured to .the arm, in any desired manner.
  • the arm 45 at its end remote from vthe link 46 is providedwith the contact element 49 arran d to engage the fixed contact 50 adjstab e inthe mounting 51, which is insulatively secured to the housing member 41 ⁇ , in any desired manner.
  • -A spring 52 has one end encircling the pin 53 projecting from the flange 47, and the other end en 'aging the arm 45 adjacent to its free en thus maintaining the contact 49 in engagement "with the fixed contact 50.
  • Oneend of the coil 26 is grounded to the frame of Vthe machine.
  • the other end of the coil isv conductively joined to the rod 57,
  • thepmoVa-blecontact arm 45 of the interrupter is connected to ground.
  • the secondary coil 35 has one end connected to ground or to the frame of the magneto, while the vother end isconnected to a .distributor, spark plug or similar device.
  • a condenser 63 isprovi'ded in parallel with. the interrupter contacts 49 and 50.
  • the condenser 63 as shown in Figs. 1 and 2, may be mounted in a depression in the base member 14.
  • a cover strip '64 of any desired 'exible material, may be yprovided over the top en onv the sides of the magneto and secu-red to t e base member 13 by screws or other devices, as shown in Figs. 1 and 2.
  • the o eration of th'edevice will now be describe reference being had particularly .to Figs.l 6 and 7. We will assume that the and the end 37 of the transformer core 33.
  • a magneto In a magneto, a rotor, a generator coil on said rotor, magnet pole pieces, a trans- .former coil, a core for said transformer'coil, A ythe ends of said core being'v adjacent to the path of said rotor at thev opposite'ends there.
  • the impulse of current from the enerating coil will be augmented. by the discharge from the condenser 63.?
  • the coil 34 will be so Wound on the core 33 that the surge of current from the coil 26 will act to oppose the yowing throughthe core 33, thus causing. a rapid reversal in -the magnetic lines extending 'through the core33, and set ⁇ l ting up a high potential surge of current vin v the secondary w1nding35. While the mannerof operation above de ⁇ scribed is the preferred arrangement, yet
  • the device will give satisfactory' results if I ⁇ the coil 34 is wound on-.the-core 33 in they opposite direction, that is, ina direction suchlthat the surge of current from the coil ⁇ 26 a d condenser 63 will act to augment the flux which is caused to flow throughthe core 33, due to the inductor segments 30 and 32- bridging the gaps between the pole pieces 11 and 12 and the ends 36 and 37, respectively.
  • the primary coil 34 arranged in this manner, the surge of current from the generator coil 26 at the time the contacts 49 and 50 are opened, will hasten the building up paths from said respectively.
  • ⁇ c 3 In a magneto, a rotor, a generator.
  • a magneto a rotor', a generator'coil on ⁇ said rotor, magnet pole pieces, a transformer coil, a core for said transformer coil, magnetically isolated from said' pole pieces, means carried '.bysaid. rotor for simultaneouslyv completing paths from said pole pole pieces to the said core -pieces to the ends of said come respectively,
  • etov-a rotor including anar- 6.
  • a second coil one endy of said second coil being grounded, a core for said second coil, inductor segments mounted'at opposite ends of said rotor armature' and arranged to simultaneously complete paths from said pole pieces to the ends of saidcore respectively, a 'circuit joining the ⁇ non-grounded ends of, said coils, and .an interrupter for controlling the flow between said coils.
  • pole pieces,A a rotor .an

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Permanent Magnet Type Synchronous Machine (AREA)

Description

Aug. l1, 1925.` v1,549,119` W. W. HAWKINS IGNITION MAGNETO Filed March 11. 1922 2 Sheets-Sheet l @l kaf . o 1 rnfm'l? I @422.22m www@ #MMW e@ T 3f dMy/fmnl Aug. 11, 1925. 1,549,119
l w. w. H AwKlNs` IGNITION MAGNETO Filed March 11. 1922v 2 sheets-sheer 2 Patented Aug.y 1.1, 192.5. l n
UNITED `STATES l y 1,549,119 .PATENT l OFFICE.-
WILLIAM w. nawxINs, or BROOKLYN, N'nw'ronx, assIoNOn-'ro wnns'rnn nLEc'rnIc coMrANY, or RACINE, w'IsooNsIN, a conrona'rIoN or WISCONSIN.
IGNITION IIaeNn'ro.
Application tiled March 11, 1922. Serial '170. 542,929. Y
To all wlwm 'it may concern:
Be it known that LVWILLIAM HMV- KINS, a citizen of the United States, and resident Of Brooklyn, inthe county of Kings and State of New York, have invented a certain new and useful Improvement in Ignition `Magnetos, of which the following is a full, clear, concise, andexact description, reference being had to the accompanying drawings, forming a part of this specification.
' This' invention relates to magnetos of the type which are commonly employed with p ofthe rotor,.permanent magnet poleV piecesl internal combustion engines for ignition purposes.
The object' ofthe invention is to provide a magneto of this character which will gen-v erate an exceedingly intense spark' yet will Anot be complicated in its construction and will consist of relatively Vfew parts. l
One of the features of the present invention is the arrangement of the transformer core with its ends adjacent to inductor elements carried at Opposite ends of the magneto rotor. E.
.Another feature of the invention resides in the circuit arrangement interconnecting 'the generator coil and the primaryv coil of Figure. 3 is a perspective view of the'rotor armature detached;
Figure 4 is -a section taken substantially on the line 4-4 of Figure 1; Figure 5 is a section taken on the line 5-5 vof Figure 1;
`Figure 6 is a schematic lperspective view and ends-of the transformer` core, showing thl relativev relations ofthe several parts, an yFigure 7 is a diagrammatic illustration of circuit employed with the device.
In th drawings,l in which like parte in the several views are indicated by the samerefercnce characters, 10 indicates the perma' nent magnets, which are of the usual horse-Z shoe or U-shape,and are mounted side byside so as to be, in eii'ect, a single magnet. The magnets 10 are provided with the usual laminated pole pieces 11 and 12. The magnets 10 and pole pieces 11 and 12, are secured in position by the base portions 13 and 14,
-which, if desired, may be formed by casting, in the usualmanner, the only require- -ment being that a cylindrical OpeningI be provided between the pole pieces 11 and 12 within whichmay be mounted the rotary element of the magneto.
Secured to the remote edges of the magnets -10 andthe base members, in any desired manner, are thel end cover plates 15 and 16. The cover plate 15 is provided with an opening 17 through which projects one end of the rotor shaft 18. Cover plate 15 is also provided with anv annular recess in which is mounted the ball bearing 20.
The cover plate, '16 is provided with an y opening 21 through which projects the collar 22 on'thev shaft 18. lThe plate 16 is provided also with an annular recess 23 within which is'mounted the ball bearing 24 for the opposite end of the shaft 18.
Rigidly secured to the shaft. -18 substantially midway between the vbear-lng members 2() and 24 is the laminated rotor armature 25 which mayfbe ofthe usual H type. On
the armature 25 are the Agenera-tor coils 26.
Coils 26 are arranged in series, and are, in effect, a single coil. Rigidly secured to the shaft 18, 1n any i desired manner, adjacent to the bearings 20 and 24, respectively, are the cylindrical su porting members 27 and 28. ounted wit in the outer periphery of the supporting member 28 are the arcuate laminated in- -ductor-elements 29 and 30.- These inductcr elements are symmetrically positioned on iopposite sides of the support 28, and each extends through an arc of substantially Mounted within .the periphery of the sup ,port 27 is a similar air of laminated induem tor elements 31 an K32, which'..areof sub stantially the same size as those moclated with the support 28, and likewise are symmetrically arranged -at opposlte sides of the support 27. The inductor element 32 1s, however, arranged slightly in advance of the inductor element 30, as shown in Fig. 6. The inductor element 31 isarranged 1n advance ofthe inductor element 29 in the same' way 'that inductor element 32 is advance i of the inductor element 30.
Mounted in the space within the upper portion of the magnets 10 is a transformer- `core piece extensions` 36 and- 37. The extension 36 has its free end adjacent to the path of the inductor segments 29 and 30, while the free end ofthe extension 37 is adjacent l `to the path-of the inductorl segments 31 and Extending through the laminations forming the rotor armature 25, atvthe opposite -ends thereof, are the pins 38 and 39. The
ends of each of the pms 38 and 39 are re.- ceived by openings in the adjacent surfaces `of the supporting elements 27 and 28, respectively. Spacing sleeves' 40 are mounted about the. ins 38 and 39 between the remote sides of't e armature member 25 'and the su rting members 27- and 28.
ounted aboutthe `right end of the shaft 18, as seen'in Fig. 1, with its free edges in sliding engagement with the outer surface of the oiset portion 23 of end 16 is a housing member 41. Inl screw threaded engagementvwith the end of the housing member 41 is the cover member` 42 of insulating.
material. Projecting outwardly from the base member .13" is a post orstandard 43,
- provided`at its outerfend with the spring linger 44 whichis .adapted to engage the outer surface ofthe cap member 42 and maintain the housing inA position, The interrupter -contactsare mounted on the housin member 41.., n
ferring to Fig. 5, it' will be noted that the movable interrupter contact arm'45 is pivotally supported on the link 46which 1n turn ismounted in the inwardly projecti'ng,ilange 47 of the housing member 41. The movable contact Aarm 45 is provided .intermediate its ends with the projecting lug v48 of insulating material which may be secured to .the arm, in any desired manner. The arm 45 at its end remote from vthe link 46 is providedwith the contact element 49 arran d to engage the fixed contact 50 adjstab e inthe mounting 51, which is insulatively secured to the housing member 41`, in any desired manner. -A spring 52 has one end encircling the pin 53 projecting from the flange 47, and the other end en 'aging the arm 45 adjacent to its free en thus maintaining the contact 49 in engagement "with the fixed contact 50.
Secured `to the shaft'18, by means of the nut 54,- is'the interru ter cam 55 which is provided at diametrically opposite sides thereof with cam projections 56 adapted, upon rotationof the yshaft 18, to operatively engage the lug 48.. Thus, it will be noted that the contacts 49 and 50 are hnormally held in engagement but are separated from each other by the co-operation of the cam projections 56 with the lug 48 twice during each revolution of the rotor shaft.
Oneend of the coil 26 is grounded to the frame of Vthe machine. The other end of the coil isv conductively joined to the rod 57,
which is insulatively mounted Within the the binding post 59 is a collar 62 which is. adapted Vto be held in firm engagement with the spring finger 58 by means of the bow spring 63. Thus, it will be seen that when the housing 41 is in position, as indicated in Fig. 1, the non-grounded end of the coil 26 will be conductively connected to the binding post 60 and through the conductor 61 to the non-grounded end ofthe primary winding 34, Due to the. fact that the spring finger 58 in. in electrical-engagement with the rod or'core 57, the insulated stationary contact ,50`Qf the interrupteris also conne'cted to the non-grounded ends of the primary coil 34 and. generating coil 26, as shown in Fig. 7. As previously explained, thepmoVa-blecontact arm 45 of the interrupter is connected to ground. The secondary coil 35 has one end connected to ground or to the frame of the magneto, while the vother end isconnected to a .distributor, spark plug or similar device.
A condenser 63 isprovi'ded in parallel with. the interrupter contacts 49 and 50. The condenser 63, as shown in Figs. 1 and 2, may be mounted in a depression in the base member 14. A cover strip '64, of any desired 'exible material, may be yprovided over the top en onv the sides of the magneto and secu-red to t e base member 13 by screws or other devices, as shown in Figs. 1 and 2. The o eration of th'edevice will now be describe reference being had particularly .to Figs.l 6 and 7. We will assume that the and the end 37 of the transformer core 33.
and 37 and core piece 33, thus tending toshort circuit the rotor element 25, and causing a still further decrease in the flux extending through the coils 26. The rapld decrease in the iuxvthroughthe coils 26 sets' up va surge of current, but as the interrupter contacts 49 and 50 are now inengagement, the coil 26 is in a closed` circuit and the surge of' current has Ano effect.-
ma-Ximumilow of Hux extends through the core 33, the interrupter contacts 49 and 50 templated by applicant, and that the inveni tion is to be limited merely. bythe scope of the appended claims. I Havlng now described my invention, wliatI claim is new andfdesire to secure by Letters'Patent of the UnitedStates is:
`1. In a magneto, a rotor, a generator coil on said rotor, magnet pole pieces, a trans- .former coil, a core for said transformer'coil, A ythe ends of said core being'v adjacent to the path of said rotor at thev opposite'ends there.
of but vseparated from said magnet pole pieces,- and means carried b l said rotor .for completing paths from sai pole. pieces to the ends of said core respectively.
2. In a magneto, a rotor, a generator coil on said rotor,` magnet ponle pieces, a tra-ns- A. former coil, a core for said transformer Y At the instant whenapproximately the coil magnetically spaced from said .pole
pieces and inductor segments comprising part `or said rotor arranged to complete l will be caused to apen by the engagement of' one of the interrupter elements 56 vWith'the lug 4.8. The coili 26 is no longer in aclosed circult, and the surge of current set up in thecoil 26 will now find an outlet through the primary coil'- 34 of the transformer.'
The impulse of current from the enerating coil will be augmented. by the discharge from the condenser 63.? The coil 34 will be so Wound on the core 33 that the surge of current from the coil 26 will act to oppose the yowing throughthe core 33, thus causing. a rapid reversal in -the magnetic lines extending 'through the core33, and set`l ting up a high potential surge of current vin v the secondary w1nding35. While the mannerof operation above de\ scribed is the preferred arrangement, yet
the device .will give satisfactory' results if I `the coil 34 is wound on-.the-core 33 in they opposite direction, that is, ina direction suchlthat the surge of current from the coil` 26 a d condenser 63 will act to augment the flux which is caused to flow throughthe core 33, due to the inductor segments 30 and 32- bridging the gaps between the pole pieces 11 and 12 and the ends 36 and 37, respectively. With` theprimary coil 34 arranged in this manner, the surge of current from the generator coil 26 at the time the contacts 49 and 50 are opened, will hasten the building up paths from said respectively.` c 3. In a magneto, a rotor, a generator. coil orjsaid rotor, 'magnet pole pieces, a transf former coil, a core for sald transformer coil, the ends of said core being adjacent to the path of'said rotor at the opposite ends thereof, and inductorl segments? comprising part of said rotor arranged. to com lete paths from said pole' pieces to the en s of said core respectively, said'segments forming the sole means magnetically linking said core with said pole pieces. v
.4. In a magneto, a rotor', a generator'coil on` said rotor, magnet pole pieces, a transformer coil, a core for said transformer coil, magnetically isolated from said' pole pieces, means carried '.bysaid. rotor for simultaneouslyv completing paths from said pole pole pieces to the said core -pieces to the ends of said come respectively,
and an interrupterfforfsaid v generator coil.v
vpolepieces-to the Yendsof said core respecf tively, a circuit joinin the end of one of said coils to the endo theother` coil, and` an interrupter for V controlling-the flow. be-
of the flux in the core 33, andwill-cause the core 33 to become thoroughly and quickly saturated, thus creating a high otentlal ivmulse of current inthe secon ary coil 35. 1th this arrangement of the coil 34, it is beheved they interrupter contacts should be `open slightly sooner than with the previouslyedescribed arrangement, in order to get the st results. v j .a
While in the drawings and in vtheabo've' description, certaindefinite details and relations of parts have been set forth, it sto "l be understood that modifications are con# l plete paths from said pole of said core-respectVeIy.
etov-a rotor including anar- 6. Ina magncto,'a rotorarmature, a gen'- erator vcoil on said armature, magnet vpole Y pieces, a transformer coil, a core for said transformer coiLfthe .endsof which core are .separated l:from said polel pieces, and inductor segmentsfxed to said rotor arma* ture at opposite sides thereof and in angularly oiset relation to simultaneously comf pieces to the 'ends 7.Inam
. mature, a. co' Onaidarmature one end of said coil being grounded, magnet pole pieces,
a second coil, one endy of said second coil being grounded, a core for said second coil, inductor segments mounted'at opposite ends of said rotor armature' and arranged to simultaneously complete paths from said pole pieces to the ends of saidcore respectively, a 'circuit joining the `non-grounded ends of, said coils, and .an interrupter for controlling the flow between said coils.
8. In a m eto, pole pieces,A a rotor .an
mature, a co a lcore for said'coil, said parts being arran so that in one position of said rotor, sai armature forms a, path between said pole lllneces, and in another p0- sition forms a pat between one of said pole pieces and one end of said core, a coil about said armature, said coils being ina series circuit; and an interrupter for breakingnsaid circuit.
In witnesS whereof,v I hereunto subscribe 2 my name this 3rd day of March 1922.
WILLIAM W. HWKINS.
US542929A 1922-03-11 1922-03-11 Ignition magneto Expired - Lifetime US1549119A (en)

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