US2429863A - Engine starter - Google Patents

Description

Oct. 28, 1947. 7 F. WRIGHT 2,429,863'

ENGINE STARTER Filed Aug. 11, 1945 1 a Sheets-Sheet 2 v I N V EN TOR. Fka NK WANG/l7 7 F. wan;

Oct. 23, 3.. 1 9479 ENGINE STARTER ets-Sheet 3 Filed Aug. 11,

INVENTOR;

- fRA/wrWe/aHr Patented Oct. 28, 1947 .E m B E L: 7 Frank Wright, East Orange, N. J., assigno'rlo Breeze Corporations, Inc., Newark, N. J a cor,-' poration of, New Jersey .v

, Application August'll, 1943,,se1-ia1 Nara-n41 This invention relates to improvements instarters -forinternal combustion engines, and more particularly to starters using expansive gasesof explosives. Such devices are exemplified in the patents to Coffman, Nos. 2,005,913 and 2,283,185, and several others of earlier date, all of which are considered as capable of extensive improvement. Oneof the objects of the present inventionis to materially simplify the construction, by reducing the number of parts, and so arrangin the parts asto be'more readily accessible and convenient in assembling and dismembering;

- A further featureis in the provision of'a spring sleeve and associated parts, held in a, manner to avoid weakening the structure and easily removable without dismantling the remaining mecha nism; Another purpose is to-produce a starter adapted for partial assemblage, permitting piston recipro cation over a period of time, by any convenient means, whereby the moving parts are harmonized and their surfaces rendered'eve'n and uniform to operatesmoothly, before the spring sleeve is entered; t

f-A-stih further object is =in the provision of a cushioning device to receive the impact of the mainmoving part, preventing upsettin and consequentmalformation f-parts to the extent of impeding, even actually obstructing action,

'- These objects are attained by the novel construction, combination and association of parts hereinafter described and illustrated in the ac companying drawings, constituting a graphical component of this disclosure, and in which:

Figure 1 is a, longitudinal sectional view, taken onthe center lineof an embodiment of the inven 'n- 6 Claims. (Cl. 123-179) Figure lois'a perspective detailview of one of the absorbing elements. V Figure 11 is a similar view of one of the'separators disposed-intermediate the cushionin elem t ic I i a i. "I 7/ Figure 12 is partial-side, partial sectional view of'a form of spring'whichmay be substituted forthe elements shown in'Figures"10* and 11.

Figure 13 is a'side elevational view of an alternative typeot cushioning spring.

Referringfin -gratr detail-to the drawings, the numeral 15 designatesa-Cylindrical base bracket,

' having an annular flange I6, provided with bolt receiving openings by' which it may be held-securely upon a supportfarranged' with respect to the drive shaftof theerigme to'be started. 7 V 'Atthe out'er forwardend of the bracket is'aninturned fiangel whileat'its-rear end is an outturned flange -1 8; in which are set a plurality of tubular dowels-l9 which pass through the flange ZUefan a.l'i '1tin er'it ri later'described.

A" cylinder '{2 l ha's' a flange 22 seated against the flange zo and aspnt clam band 23, having inturned' 'lateral ed es, maintains the three flangesin juxtaposition; therebyuniting the cylinderto'thebasebracket'; i 1 The outer, rearfend ZQ of the cylinder is closed ans provided with 'a screw: threaded axial boss Figure 215 a front elevational view of the driv ing end, drawn to an enlarged scale. I

, e 3, is a transverse-sectional view taken approximately on line 33 of Figure 2.

blank. V V

Figureffi is a side view of the completed spring s e v I Figure 6 is aside .elevational view of the spring assembling tool, partially in section.

Figure- 7: is aplan'view of the hollow screw lock washer; V I i "FigureSis a side View, similar to Figure 1', but broken away toshow a cushioning means to sorb the impact of the drive member.

Figure 9 is a partial side, partial sectional view of-the shock absorbing means drawn to anene H Y L a,

larged scale. 3

" Figure 'fiis a plan VieW 'Qf the spring sleeve communicate withthe interior'o'f the cylinder Exhaust takes place through an opening 30," controlled bya' valve 3I","its stem 32 being-slid}- able in a sleeve 33 having vents 34 open to the passageT2 8. The openingcommunicates with the outside atmosphere to 'efiect the exhaustactio'n; 7L .-.1I. f... If: I .J I --The valvestem-32 contains a crossbore 35 in whichtwo loose" spherical elements 36are oppo-I sitelfystressed-by an intervening helical spring 31, whereby they are caused to engage in an annular groove 38 in'the sleeve 33, in the manner of spring detents, 'when theivalveis in an extreme open position.

Inthe frontof-the-bracket [5, against the inner' side-of the'fla'nge l 1, issetthe fixed outer member of an anti-frictionalthrustbearing 39, the inner member being retained in plac'e by a"spring ring 40 set in a groove in thebracket 4 r5 "Acylindrical-barrel .4 Us slidablyl and ro'tatably mounted in the bearing andiprovided'with an: outstanding 'annular 'flange 42' on: its inner, rear end adapted to contact :the' bearing 39' wheniin- 'its' eXtrenie' forward position; n

The outer, projecting end of the barrel is provided with an annular row of teeth 43 to clutchingly engage mating teeth on the end of the engine drive shaft (not shown).

An abutment ring 44 is fixed in the base bracket I5, having its flange 20 seated against the inner end of the bracket and is formed with a cylindrical extension 45, entering the bore of the barrel 4|, but out of Contact, due to the interposition of a sleeve 46.

The opposite end of the ring 44 contains a recess 41, and a cylindrical projection 48 provided with coarse pitched square screw threads 49 which act as guides for similar threads formed on the outer side of a driving member 50.

This member 50 has an enlarged circular head 5| set in the under side of a piston 52, movable in the cylinder 2| which is provided with the usual ring packings 53; the piston is normally retained outwardly, adjacent the closed end of the cylinder, by a stron coiled compression spring 54, seated within the piston at one end and at the other in the recess 41. v V

Thedrivihg meinber 50 is provided on its inner surface with helical threads or splines 55 co-operative with mating threads or splines 56, on a driven member 58 whereby the latter is moved longitudinally and falso rotatively. I

The driving member-5 0 engages, at its forward end, an extension of thedri ven member 58, which terminates-at its outer end in ahead 59, fitting an opning in the barrel 4| to transmit motion to it.

Also carried by the piston is an axial sleeve 60 having a closed conical inner-end or head 6|. -A valve rod liz isfixed in the-valve stem 32 and provided with an enlarged head (i3, cushioned in its action by coiledcompressionsprings 54 ;at either range'of its-motion within the-sleeve 60. l

A shoulde'rfii, reachinginwardlyfrom the wall of the extension w, actsas an abutment for the head 6| of the-sleeve, when the valve '31 engages its seat, limiting thei novement of the sleeve 60, and also the piston, an outward direction.

. Screw-threadedjnto the bore of the driven member 58 is a hollow screw having a flanged head 61 which makes contactyvith a lock washer B8-, hav-in a plurality of radial teeth 159 in its periphery and provided with rigid dowel pins 68' to fit openings in the end of the driven member head '5 9,;the teeth being selectively adapted to be upturned through a notch 10 in the head 51 to prevent loosening of'the screw, the head of which is provided with openings H for a spanner or similar wrench.

The screw 55 has a bore 1-2 and "a hollow extension 13in which is an annular peripheral recess 14. A screw plug 15 is fitted to engage in the outer portion of the screw 66 and is held from jarring loose by akeepe'rspring ring 15 set in an annular groove int-he screw. -A spring sleeve 11 is entered over the screw extension 13 and is formed with a bead '18 to engage the "recess 14.

The sleeve Tl isformed from:sheet'spring material to present a plurality of fingers or prongs l9, shaped asshown'i'n Figure 5, these fingers having 'outturned terminals 80, and outbowed elements 81 adapted to-contact the inner wall ofthe drive member extension 58.

The function of .t'h'espr ings 1-9 is toen'gag'e the conical head 5 I a manner so that the -n'iovement of the piston 52 will cause a longitudinal movement of :t-he driven member :58, to the extent required, that is; 'to cause the clutch teeth '43 to engage the driving member of the'engine, at

which time the barrel flange 42 makes contact with the thrust bearing 39; after this the springs will yield to permit passage of the head BI and its sleeve 60.

It is to be understood that in the initial forward movement of the piston 52, the driven member 58 is not caused to rotate with respect to the driving member 50, which turns only after the resistance of the springs 79 has been overcome.

Such springs have been usually secured within the driven member 58, by riveting, which has a tendency to weaken the parts and, in case breakage occurs, access can be had only by removal of most of the main elements of the structure through its rear.

It is to be noted that the present structure avoids such contingencies and further permits assembly and actual working in of the parts before insertion of the springs. Such insertion and removal are greatly facilitated by the use of a special hand tool (see Figure 6) which comprises a frame -82 having a'flanged base'83 from which projects a-lug8-4 suited to engage the openings 1| in the screw head 61.

The frame 82 contains an axial bore 85, a counterbore 86 in its outer end portion, and is flattened on two opposite sides 8'! and provided with central, diametrically drilled openings 88, in which is set a handle bar -89.'

Freely movable in the bore is a sleeve 90 having an enlarged head 9*! adaptedto be seated on the shoulder of the oounterbore 86, while the lower extending end I is provided with screw threadsSZ suited to fit the internal threads of the hollow screw 66. e n 4 'Sli-dable through the sleeve 90 is a rod 93 acting as a guide for the tool and springs 19, the rod being slidable through the bore 12 of the hollow screw 55, and normally pressed outwardly by a spring 94, its upper end being seated against the bar BS n :In operation, after the structure has been fully assembled, except the spring elements 1'l 'l'9, the plug 15 is removed and the centering rod 93 inserted through the bore l2 of the hollow screw 66-, whereupon the lug 84 is engaged in the opening 10 of the hollow screw, and upon actuating thehandle bar 89 of the tool, the screw may be withdrawn. 7

Thereafter the. spring sleeve is passed over the rod, its head entered into the groove 14 of the hollow screw 55, the lug 84 set in the opening 10 of the screw flange, and the screw 66 seated in position to be-locked by one of the-lock washer elements 69 then the tool is withdrawn and the plug 15 inserted.

It will be understood that removal of the springs 19 is easily and quickly done by reversal nut-like hub element mnemmm the outer splines or threads 4-9, them to-bind on the splines or threads of the drive shaft, and such repeated hammer-like blows may eventually prevent rotation and reciprocation of the drive shaft.

The inner end of the drive shaft 50, striking against the end 59 of the driven shaft 58, also becomes deformed or upset, creating --further 5. binding, to the extent of preventing proper action of the engine startergi' These harmful conditions are overcome by the device shown in Figure S'and those following, in which a thin walled cylindrical casing I is fastened by its out standing base flange IOI to the inner face of the abutmentring 44, the casing having an inturned annular bead I 02 at-;its opposite end-. t g 1 Fitted to :move freely with; the casing'I00 is t eets W3 ofarlu e rin 104 va le over the pe rlipheral surface of the internally threaded element 48, and is provided with an inreaching annular flange I05, which clears the drive shaft 50.

Mounted to move freely within the casing I0, circumjacent the bracket element 48, are a plurality of fiat, highly elastic rings I06, such as synthetic rubber, having interposed between their side faces rigid washers I01, slightly larger in diameter and of lesser thickness, constituting a stack of cushion elements, seated at one end against the flange 44 and at its opposite end in contact with the slidable flange I03, which moves inwardly of the casing, under impact of the drive member, preventing its deformation by absorbing its energy at the end of its stroke.

From this it will be seen that the hammer-like blows of the drive shaft, including its head 5|, are very materially cushioned, preventing damage to the splines and likewise to the stationary parts engaged by it.

In the modification shown in Figure 12 a series of inclined fiat springs I08 are substituted for the elastic cushion, these elements being contained within the casing I00.

Each spring I09 is shaped as the frustum of a cone, their outer edges being in contact, as at H0, while the inner edges abut one another, as at III.

Figure 13 shows another spring device, consisting of a strip II2 of material of such thickness as to be contained in the casing I00 and of considerable width, the strip being helically wound, each convolution spaced as at II3 from the next adjacent, and its ends II4 finished square across.

While the foregoing is descriptive of the best known embodiments of the invention, it is not to be held as restrictive, but rather suggestive, within the scope of the annexed claims.

Having thus fully described the invention, what is claimed as new and sought to be secured by Letters Patent of the United States is:

1. An engine starter comprising in combination with a gas expansion motor, including a cylinder, a piston operable therein, a drive member actuated by the piston, a driven member engaged therewith, and a toothed clutch associated with said driven member to impart rotary motion to the engine to be started; a screw threaded into said driven member, a sleeve having a plurality of spring fingers rotatably connected with said screw to extend inwardly of said driven member, and a conically headed member fixed to said piston, said conical head frictionally abutting the free ends of said fingers whereby said driven member is initially caused to advance longitudinally and after passage of said conical head through said spring fingers to rotate without further advancement.

2. An engine starter comprising in combination with a gas expansion motor, including a fixed cylinder, a piston therein, a drive member actuated indirectly by said piston, said drive member having a limited lineal movement and an unlimited rotative movement, a driven member engaged threwith, a toothed clutch fixed on said. driven member to impart rotary motion to the engine to be started; a hollow screwthreaded axially into said driven member, releasable means to retain said screw when entered therein, a series of integrally connected spring fingers engaged on said screw to extend into said driven member, and a tubular member carried by the piston having an enlarged'conical head in contact-.with'the inner. ends of said spring fingers during the lineal movement of said driven member, saidfingers yieldin to permit passage of the head therebetween at the beginning of rotative movement of the driven member.

3. An engine starter comprising in combination with a gas expansion motor, including a fixed cylinder, and a piston therein; a reciprocative drive member, a driven member engaged therewith having a clutch engageable with the engine to be started, a hollow screw removably engaged in said driven member, said screw having a flanged head, a fixed washer interposed between said head and driven member, means on said washer to lockingly engage said head to retain the screw in adjustment, a series of inreaching spring fingers supported by said screw, and a conical headed sleeve fixed on said piston initially in contact with said spring fingers, said fingers yielding at the end of the lineal movement of the driven member to permit passage of said head therebetween as the piston moves forwardly.

l. In an engine starter of the type described, including a reciprocative drive member, a driven member engaged therewith and a clutch combined therewith; a hollow screw set in said driven member, said screw having a front part containing an annular recess and a rear part internally threaded, a sleeve having a bead fitting said recess, a plurality of spring fingers integral with said sleeve to extend into said driven member, a starter member carried by the drive member having a conical head in frictional contact initially with said fingers and capable of eventually passing therebetween, at the end of the lineal movement of the driven member, and means to lock said screw when set;

5. In combination with an engine starter having a clutch member mounted for lineal and rotative movement and means to initiate such linear movement and thereafter a rotative movement; a hollow screw threaded axially into a driven member attached to said clutch member, a flanged head on said screw provided with a peripheral notch, and at least one wrench receiving opening, a washer fixedly interposed between said head and clutch member, said washer having a plurality of peripheral teeth selectively engageable in the flange notch, said screw having a cylindrical inner portion provided with an annular recess and an internally threaded outer end, a sleeve having means to engage in the recess of the screw, a plurality of spring fingers integral with said sleeve to extend inwardly therefrom, a, starter member having a conical head in frictional contact initially with said fingers and capable of eventually passing therebetween at the end of the lineal movement of the driven member, and a plug fitting the internally threaded portion of said hollow screw;

6. An engine starter comprising in combination, a piston adapted to be driven by an expanding gas charge, a reciprocable and rotatable driven member having one end arranged to engage a rotatable member of. the. engine, a sup-- porting member connected to said one end of:

the driven member andreadily detachable there-F immia set of spring fingers mounted on said supporting member and extending within said 5 drivem member, and an elongated member connected to. the piston and having a taperedhead poxtion disposed; initially in contact with said' spring fingers and, adapted to press against said fingers, until the: end of the lineal travel of: the foi.

driven member and; thenspread; them apart and pass. between them in response tofonwarldimotion of the: piston.v

WRIGHT.

REFERENES @ITED Theifollowing references are of record in the file of this patent":

UNITED SIA'IPI-BS PATENTS:

Niamber' Nemre Date 2283,1535 Coff'man May 19; 2,300,002 Nardone Get; 27', I942 139513030 Nard'on'e- Mar. 13', I934 2;1-9-7-;1 5'5* Nardbn'e Apr. 16 1940 230053913 Goifmain Ji'me25', 1 935

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