US 2944428 A
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Description (OCR text may contain errors)
J. E. ANToNlDls ETAL 2,944,428
ENGINE summa Filed oct. 11, 1957 July l2, 1960 vENToRs JoH/v E. ANTON/Dls r i. BY E BERT/IULM 211...
ATTORNEY United l SeteSPafmf' ,2,944,428 ENGINE *STARTER John E. Anmnidis and Robert 1A. zum, Anderson, and., Y
This invention relates to engine stalztersand .morepar- .tieula'rly lto asta-rter drive ofthe inertia typefwherein `the pinion -is automatically propelled .into and-.from Aer'igageymentV with :the ,gear of vthe engine to be :.stfarted'.,
.It is an Aobject of the present invention'tofarrangethe' parts of a starter drive :on a threaded starting..motor .Shaft fso .the engine .to be cranked may beftc'ranked fin either direction of rotation.
Another .object of the present invention is to..arrange the resilient members of aninertia .star-'ter' drive `so .a yielding ...connection is formed y,when-.the ,pinionismoved by thestarter motor and ya `nonyielding. yconnection Vis formed when the pinion is 4rotated-by the engine. This will .prevent rebounding .of Vthe pinion Egear into -engagementwith the engine gear after the engine .becomesselfoperative.
A ,A ,ftirther-objectof the present invention is to provide Aan inertia Ldrive with a torsion return. ,spring anda resilient .connection between v.the piniongear. fand. its.. drive `which will .permit .a limited rotation betweenthe. ,pinion .gear and its drive when the pinion vis moved -by thestart- Ling motor and a non yielding connection. is formed when the vpinion is rotated bythe engine.- This aid. the ',pin'ion in demeshing from `the Vengine, gear andl will :prevent the pinion from .reboundinginto the engine ,gear after the engine becomes .self-operative..
Another object of the :present `inventionis :to v .r'nro'yide the starting motor shaft with a .thread portion and- ,a smooth 'surface portion and .to support .a sleeve which axially moves on the thread portion, fon the 'smooth .surface portion With a nylon lbearing so the pinion which rides upon the sleeve will be supported when itv is jinmes'h with a gear ofthe engine to be started.
Another object of the present invention is to provide a shoulder 'between a :reduced portion of ythe shaft and the remainder of Athe shaft which sholder'vvill act as fa stop to limit the `movement of a sleeve which is V.threadedly connected to the reduced lportion of the shaft.
Patented July V1a, 1960 Y Figure 3 is'a View taken alonggli'ne iin' y:Figi-Ifo" 1.
"Figure` 4is`fa cross-sectional View 'ofi-ia `single vstai-ter drive *sliow'inga inodiiication 'of the drive-lin* V'Figure l'.
In I'the embodiment shown 'fin' Figures -l `and '2 'ofthe drawings, the shaft Z0 is adapted to be rotatedinf-cith'er direction lby a conyentionalttype starting motor, not shown. The shaftil `has afrednce'd diameter portionJ 22 whichist separated :from `the main portion Q4 -of vthe 'shaft 'by the shoulderj-Z. 'The reduced portion-of theShaft is provided-with-threaded portionsY 2-8 -and '30 wliichfiare separated eaeh 'other *byJ 4a smooth `surface' portion 82., :The threaded: -portions '28 and"3'0"3in the'enibodi- Irrentts'hown'iaree preferably formed-iin the materia-loffthe jshaft '2ll This "arrangenrcn't will; provide a certain econ- 'onlyin-manuff-actre 'andf will Areduce the 'over-alls'izeof f lthe remaining parts o'f the` starting, drive. AThe. threaded portions 'andf'lt Yare located opposite' sides 'of .a vgeen-3124 which'is' connected to the engine to be started lwhich",iis-not shown. lIn conventional practice, ythe` gear "34 would i-be connected tofthe' "ywheel 'and designated as a-'ring gear. .The shaft '2:0 mayY also. begroov'edA as at and 38; lto :receive 'C-shaped `metal ringsj4ll` and' 42. The, ring 40 will `bepresse'd against the shoulder L26 and will preven tfda'niage thereto whenv the shoulder 'acts asa A stop; fiihering'42'isofa-hardened metal type andwill grooves which receive the C-shapedv rsnap rings 44 .and
.46j arranged to position one of :the ends. 'of the 'torsion springs. and; 49` respectively as shown. The function of'thesesprings `will become "hereinafter apparent.
.It to beunderstood that 'like numerals and7 :functions A further object of the present inventionlis .toprovide i preferred embodiments ofthe lpresent linvention are clear- 1y shown.
Inthe drawings: Y Figure 'l is a cross-sectional view vo'i' a pair f starter `drives according to the present inventionwhic'h are arranged on opposite sides` of a gear'that isconn'ected to the engine-to be started.
Figure .2.` is a view of the drive fparts in Figurefl wherein one of the drives is in lmeshing engagement with i `the engine gear.
dfthepartsto whichthe numbered parts relate willapply tothe 'parts of .the drive 52.. The drive 5l) includes the coupling 5'4, thepinion gear .56, the shell 58, .theresilient kmembers 6D and the snap ringf64 which is received in `the internal groove ddngthe shell 58 tohold the'parts of lthe -drive'assembled y l The coupling 54' formed as shown has a centralhub 68` that is internally threaded to threadedly engage the threaded .portion 2'8. The outwardly extending flange "70 on huh is provided wi-thy av slot 72 to receive. fthe other vendaof the torsion spring 48 which has its convolutions surrounding 'the shaft `2t) when the driveY 50i-is 'inthe normal or at rest position. Extending .fromthe Lange V`toward the pinion gear 5'6 are lugs. 74. The drive v.50
in vFigure lhas .four spaced lugs 74. These lugs are designatedas lugs ,74A and' 74B and extend substantially radial- .ly from thei'hub 68 and are spaced as shown in Figure-3. The lugs 74A and 74B in 'the embodiment shownare providedby the extending arms of a pair .of U-shaped parts 76 which have their central portions secured as 'by welding 'to the ange 70. I
The .shell 58 is Vgenerally cup-shaped to have a vbottom wall 178, a. central opening 80' inthe bottom wall 478 and `the internal groove 66wh'ich lis formed onthe sidewall 82; opposite sides thereof and adjacent .the bottom wall 78 is struck in to provide apair of'inwardly extending lugs 84 which `extend substantially radially inwardly` as in Figure/3. When the partsof thedriye 50 are'ass'enrb'led, `the "lugs 84 each 'will vhave one surfacer in engagement with one of thelugs 74A. Thus, 'one--snrface-oflngs 84"willbe in metal tometalconta'ct with the lng's'ifdl.
vPositioned between the' other surface of flugs 84A andthe fflrgs 74Ba1'ethe resilientfmeinbersfll. f'
The material of the side Wall 82`jon diametrically.
central bore 86 sized to slide on the sleeve bearing 87 which is positioned on smooth surface portion 32 of shaft 2t) and which is formed of nylon material or any otherrsuitable bearing material. This bearing may be molded in place on the shaft or may be fitted thereto by any other well known mechanical expedients. The teeth of the pinionare formed with the conventional chamfers to aid in the meshing and demeshing with the ring gear 34.
The resilient members 60 are shaped as shown in Figs. 2 and 3. These members 60 are formed of rubber-like or elastomeric materials. The particular materials from which members 6) may be formed are Well known and may consist of natural or synthetic rubber or other suitable plastics or combinations thereof which are compounded and cured to provide the proper degree of resiliency. The members 60 are arcuate in shape and have `flat end walls arranged to engage the lugs 84 and 74B.
The inner surface 88 is curved to engage a portion of the cylindrical outer surface of hub 68. The outer surface 90 is also curved and is maintained normally spaced from the complementary cylindrical surface provided by the inner surface of side wall 82. The spacing between l Y the outer surface 9@ and the inner surface of Wall 82 is maintained by the lugs or bulbous portions 92 which extend outwardly from the surface 90. The parallel end walls 94 have the spaced extending ribs 96 thereon. The ribs 96 are maintained constantly in engagement with the flange 70 and the bottom wall '78 as in Figure l and are deformable to permit a slight axial movement between the hub 68 and shell 58.
When the shaft 28 is rotated in the direction of arrow 98 in Figure 3, the drive 50, because of its inertia will not rotate, but will move axially on the threaded portion Z8 to the right to the position shown in Figure 2. When the pinionis completely moved to the right, it will be in mesh with the ring gear 34 and the convolutions of the spring 48 will be tightened about shaft Ztl. The
shock which accompanies the sudden stops of thepinion gear as it is moved into the full mesh position is absorbed by the resilient members 60 of drive 52. After the pinion 56 is in mesh with the ring gear 34, the continued rotation of the shaft 2&9 will rotate the hub 68. The rotation of the hub 68 will be transmitted through lugs 74B against the resilient members 60 to circumferentially compress the members '6h against lugs 84. When the resilient members are thus circumferentially compressed, the surface 96 will move radially outwardly to at least partly fill the space between the surface 90 and the inner cylindrical surface of the side walls 82. Thus, a resilient connection is formed between the lugs 74B and 84 when the pinion gear 56 is driving the ring gear 34. 1n event tooth end abutment occurs between the pinion gear 56 and the ring gear 34 when the pinion gear 56 is being moved forward into meshing position with the ring gear 34, the resilient members 68 will be slightly axially and circumferentially compressed before the pinion gear 56 rotationally responds -to the rotation of shaft 2t). This compression of the resilient members 651 will aid the pinion in moving from its tooth end abutting position into full meshing position.
After the axial movement to the right of pinion gear 56 stops, the pinion will respond to the rotation of shaft 20 and rotate gear 34. When the engine becomes selfoperative, ring gear 34 accelerates and will tend to have a greater rotational speed than pinion gear 56 and shaft 20. This relative rotation will cause the drive 5t) to be rotated on thread portion 28 and move to the left from the position in Figure 2 so the pinion gear 55 will move from its meshing engagement with the ring gear. The spring 48, which was previously stressed when the pinion y gear 56 moved into the meshing position will aid the movement of the pinion gear 56 to the left. During this period, a relatively nonresilient driving connection will be formed between the pinion gear 56 and the hubp68.
4 This nonresilient connection is the result of the metal to metal contact between lugs 74A and lugs 84 and will impart a positive nonresilient rotative impulse to the hub to eliminate the back lash or kickback which occurs when the pinion is connected to the hub by a connectlon that is resilient in both directions of rotation` We have determined that a nonresilient connection, as described, between the pinion gear 56 and hub 68, will eliminate the rebounding of the pinion gear into the ring gear after the engine becomes self-operative.
4 The threads of both threaded portions 28 and 38 are left-handed. Therefore, when the shaft 28 rotates clockwise as viewed in Figure 3, the drive 5@ will advance from left to right and drive 52 will be pressed against the ring 42. In this connection, itis noted that the torsion springs 4S which normally loosely surround the shaft 20 will normally maintain the drives against the rings 40 and 42 when the shaft 20 is not rotating. When theshaft is rotated to move one of the drives toward the gearv34, the spring associated with the moving drive will become 'extended and its ccnvolutions decreased in diameter.
The springs will thus aid the pinion gear drive in demeshing from the ring gear after the engine becomes self-operative. When the shaft Ztl is rotated in a clockwise direction, the drive 52 will advance from right to left as shown in Figure l. The parts of this drive 52 will function in the same manner as the corresponding parts described for drive 50. It is clearly apparent that the above arrangement will cause the engine to be cranked in either direction of rotation depending on the direction of rotation of shaft 20.
In the embodiment shown in Figures 4 and 5 of the drawings, the shaft 12o is arranged to be driven in one direction of rotation only, indicated by the arrow in Figure 5, by a starting motor, not shown. The drive 122 'includes a sleeve 124 which is internally threaded to engage the threaded portion 126 of the shaft 120. A flanged member 128 secured to sleeve l124 has lugs 130 which radially extend from the opposite sid'es of sleeve 124 and extend longitudinally along the outer surface of the sleeve toward the pinion gear 132 in a plane parallel Vwith the axis of the shaft 12h. VThe purpose of these is, one surface of each of the lugs will be in engagement vwith a resilient member 138 while the other surface Will be metal to metal contact with an adjacent metal lug. Secured to the outer surface of coupling 134 is a shell 140. This shell 140 will have its free end riding upon the flange 128 and will completely enclose the lugs 136 .and and will provide enclosed areas or chambers 142 between the shell 140, the outer surface of the sleeve 124 and the adjacent surfaces of the lugs 136 and 130.
Positioned' within each of the chambers 142 are resilient members y138. Each of these members 138 is formed of a suitable elastomeric compound such as the well-known natural or synthetic rubbers, a suitable organic 'plastic or mixtures thereof which are compounded to provide the proper resilient `characteristics thereto. The
-members 138 are sized to not completely ll the spaces 142. The members 138 have provided lugs or bulbous yportions 144 thereon. These lugs 144 are arranged to 70.
engage the outer shell V to provide an open space 146 between the outer surface of members 138 and the inner surface of the shell 140. This space 146 will permit the rubber material forming members 138 to move radially .outwardly when abutment 136 is rotated relative to abutment 130.` It is well known that rubber isvvirtually uncompressible. This space will permit the rubber to provide the yielding restraint to oppose the movement between the abutments 136 and 130. The members' 138 are also provided with ribs or ridges 147 which have their apexes in constant engagement with the members 128 and 134. These apexes of ribs 147 are arranged to provide an increased resistance to movement proportional to the distance moved when the coupling 134 and flange 128 are moved toward each other.
The shaft 120 is also provided 'with a stop, portion 148 which is engaged by sleeve 124. The drive parts are held assembled on sleeve 124 by the snap lring 149 which isV arranged to permit the pinion gear 132 tovmove axially on sleeve 124 toward flange 128. A conventional fixed stop means 150 on the free end of shaft 120 will limit the axial movement of they drive to the right. In this embodiment the torsional spring 48 as used in the embodiment shown in Figure l is replaced by a compression spring 152.
The parts of the starter drive will have a similar operation during meshing and' demeshing operation with the ring gear 154 as described in the embodiment shown in Figure 1.
While the embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other Vforms might be adopted.
What is claimed is as follows:
1. In an inertia type starting motor drive, comprising: a nut having a threaded engagement with a threaded portion on a starting motor shaft, outwardly extending lugs Von the nut, a pinion gear slid'able and rotatable over a smooth portion of the shaft, a shell connected tothe pinion, and inwardly turned lugs integral with and extending from the shell interposed between the lugs on the nut and in metal to metal contact therewith, said lugs forming a direct drive between said nut and pinion.
2. In an inertia type starter drive, the combination comprising: a nut having a threaded engagement with a threaded portion on a starting motor shaft, outwardly extending lugs on the nut, a pinion gear slidable and rotatable over a smooth portion of ,the shaft, a shell connected to the pinion, an integral inwardly turned lug on the shell having a surface in contact with a lug on the nut and a resilient means disposed between the lugs on the nut and on the shell urging the lug on the shell into surface contact with the lug on the nut, said resilient means forming a resilient drive in one direction of movement of said pinion and said lugs forming a direct drive in an opposite direction of movement of said pinion.
3. In an engne starting apparatus, the combination comprising: a rotatable shaft, a threaded portion on the shaft, a sleeve having an outer smooth surface threaded on the threaded portion and axially movable on said shaft when said shaft is rotated, spaced lugs on the sleeve, a pinion gear freely movable axially and rotatively on said sleeve, spaced lugs connected to said pinion interposed between and in contact with the lugs on the sleeve, a shell connected to the pinion and enclosing said lugs to provide a confined space between adjacent interposed lugs on the sleeve and pinion, and a resilient means in the space between the adjacent lugs to provide a resilient connection between the pinion and sleeve in one direction of rotation only. y
4. In an engine starting apparatus, the combination comprising: a rotatable shaft, a threaded portion on the shaft, a sleevehaving an outer smooth surface threaded on the threaded portion and axially movable on the shaft when the shaft is rotated, a pinion gear'freely movable axially and rotatively on the sleeve, a flange on the sleeve, spaced abutments extending from. the flange longitudinally along the outer surface of the sleeve toward said pinion, spaced abutments connected to the pinion extending toward the flange and interposed between the abutments on the ange, a shell connected with the pinion and enclosing said abutments to provide a plurality of confined' spaces between the adjacent interposed abutments on the pinion and flange, and a resilient means yieldably resisting longitudinal movement of thepinion on said sleeve and sized to permit a limited free rotary movement of the pinion on `the sleeve in one direction of rotation only.
5. In a starting apparatus for an engine, the combination comprising: a rotatable shaft, a nut threadedly connected with said shaft and adapted to be moved axially on said shaft a predetermined distance in response t0 relative rotation between the sleeve and shaft, a pinion gearfreely movable on said shaft and movable into mesh with-a gear connected with the engine to be started,
a means resiliently connecting the pinion and nut and a torsion spring connected between the shaft and nut for aiding the movement of the pinion from its meshing engagement with the gear after the engine becomes selfoperative.
6. In a starting apparatus for an engine, the combination comprising: a rotatable shaft, a nut threadedly connected with the shaft and adapted to move axially on said shaft in response Vto relative rotation between the' v shaft and nut, a pinion freely movable on the shaft and movable into meshing engagement with a gear connected with the engine to be cranked, a torsion spring surrounding said shaft and connected with the nut and shaft for yieldably opposing movement of the pinion on the shaft and means connecting the pinion and nut.
7. In a starting apparatus for an engine, the combination comprising: a rotatable shaft, a reduced portion on said shaft having a shoulder separating the lreduced portion of the shaft from the remainder of the shaft, a washer engaging said shoulder, a threaded portion on said reduced portion adjacent the shoulder, a smooth surface on said reduced portion, a nut having internal threads engageable with the threaded portion and the smooth surface portion, said nut being axially movable on the reduced portion of the shaft in response to relative rotation between the shaft and nut.
8. The combination as set forth in claim 4 wherein the resilient means consists of rubber-like members having oppositely extending ridges in engagement with the flange and pinion which are adapted to compress and yieldably maintain pinion and sleeve axially in position.
9. In a starting apparatus for an engine, the combination comprising: a rotatable shaft, a reduced portion on said shaft forming a shoulder separating the reduced portion of the shaft from the remainder of the shaft, a threaded portion on said reduced portion located adjacent the shoulder, a nut having internal threads engageable with the threaded portion, a pinion rotatable and slidable on said shaft and driven by said nut, resilient means disposed between said pinion and nut for taking up axial shock therebetween, and a torsion spring having one end thereof connected to and engaging said shaft and having an opposite end `connected with said nut for urging said nut toward said shoulder.
' References Cited inthe le of this patent UNITED STATES PATENTS 1,625,793 Chilton Apr. 26, 1927 1,807,772 Chryst .Tune 2, 1931 1,844,543 Codrington Feb. 9, 1932 2,237,816 Getzet `al Apr. 8, 1941 2,847,985 Strang Aug. 19, 1958