US2461784A - Engine starting device - Google Patents

Description

Feb. 15, 1949: E, STR ED 2,461,784

ENGINE STARTING DEVICE I Filed April 18, 1945 IN V EN TOR.

C L lFFoeo 5.572.550

ATTORNE Ys Patented Feb. 15, 1949 UNITED STATES PATENT OFFICE ENGINE STARTING DEVICE Clifford E. Streed, Minneapolis, Minn.

Application April 18, 1945, Serial No. 588,937

10 Claims. 1

This invention relates to new and useful improvements in engine starting devices and more particularly to such devices for starting the in-- ternal combustion engines of miniature airplanes and the like, whereby such engines may be quickly and conveniently started with a minimum of eifort and without danger of damaging the propeller.

.An important object of the present invention is to provide an engine starting device of the class described, comprising a drive member having means for aligning it with the propeller and provided with an element adapted to engage and rotate the propeller when the device is set into motion.

A further object of the invention is to provide an engine starting device for airplane engines comprising a drive shaft having means at one end for axially aligning it with the propeller and carrying an element which is offset from said shaft and arranged to engage and momentarily drive the propeller at high speed, when the shaft.

is started, thereby to start the engine.

A further object is to. provide a device of the.

out of the path of the propeller blades by said blades when the propeller is set into "motion by ness of the device whereby it may conveniently element being adapted to be moved out of the path. of the propeller blades when the engine is.

started whereby the propeller can not be damaged by the starting device, when the engine initially A further object is to provide an engine starting device comprising a shaft having its major portion supported with a tubular member adapted to serve as a handle, and said tubular member havinga suitable spring mounted therein 'for driving the propeller when the spring is released, after winding, and a pair of shaft engaging elements being pivotally mounted on the shaft in spaced relation and having a relatively light spring normally retaining them in driving relationv to the propeller blades, and manually operable means being mounted on the handle for releasing the drive spring whereby the shaft is momentarily quickly rotated thereby to impart rotary motion to the propeller to start the engine, the tension in said relatively light spring and the mounting of said elements being such that said drive elements maybe quickly moved thestarting of the engine.

A further object is: to: provide such adevice which is extremely.;.-simple and inexpensive. in

construction andwhich; maybe operated by an inexperienced personxto-quickly start a small airplane engine, whenlapplied to the propellerv .or shaft thereof, without '..danger of damaging the propeller blades or the device, when the engine suddenly starts.

Other objects of the invention reside in the simplicity of the device, and the ease with which it may be attached to the propeller or engine shaft and quickly operated to start the engine; -in the provision of such a device embodying a.

free wheeling action,. whereby it can not damage the propeller blades when the engine suddenly starts; in the compactness and lightbe carried in apocket when not in use; and in the provision of such adevice which is substantially indestructible and positive in action and provides an extremelyv practical device for, quickly starting substantially all types of small. internal combustion engines to which the device may-be applied.

Other objects of the invention will appear from the'following description and the'accompanying drawing and will be pointed out in the annexed claims. I v

In the accompanying drawing there has been disclosed a structure designedto carry outthe various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown, as various changes may be made within the scope of the claims which follow.

In the drawings: Figurev 1 is a view showingthe preferred construction of my novel engine starter;

Figure 2 is a sectional view substantially on the line 22 of Figure 1; v

Figure 3 is a---detail sectional view on the line 3-3 of Figure 1 with the propeller omitted;

Figure 4 is a detail sectional view on the line 4-4 of Figure 1, showing the drive elements in driving engagement with the propeller blades;

Figure 5 is a similar view on the line 5-5 of Figure 2 showing how the drive elements are moved out of the path of the propeller blades when the engine suddenly starts;

Figure 6 is a view showing a modified driving connection between the drive shaft and propeller drive elements;

Figure '7 is a detail sectional view on the line '|-1 of Figure 6;

Figure 8 is a detailsectional view showing another form of driving connection between the drive shaft and propeller drive elements; and 1 Figure 9 is a cross sectional view on the line 9-9 of Figure 8.

The novel engine starting device herein dis closed is shown comprising a tubular supporting member 2 which constitutes the handle for the 0 may be supported directly on the shaftand retained in position thereon by abutment-elements 1 shown formed by upsetting portionsof the-shaft; shown in Figure 2. The intermediate bearing collar 5 may be similarly supported in position on the shaft by similar abutment elements i.

A drive: springt is coiled about-the drive shaft" as best showndn Figure-'2; and-has one end anchored to the tubular handle portion-2 as indi-. cated at; 9. The oppositeend of the spring is drivingly engaged with the shaft 3'by reducing its diameter as shown, thereby to provide a friction driving connection between that end of the springandthe shaft. By mounting the drive spring 8", as shown in Figure 2, said spring may be wound'up to store energy therein by grasping the i 3 handle 2 in one hand and with the other rotating theshaft in one direction, as willbe understood.

Means is provided for locking the shaft against rotation when the spring 8 hasbeen wound up.

Such meansis shown comprising a spring I l coiled about'the shaft between the collars i and '5 and having one end anchored to the wall of the handle 2. The opposite end of the spring ll projects laterally through a slot l2'in the wall of the handle and is provided with a finger grip iii. The spring I l is so wound about the shaft that it normally frictionally grips the shaft and-locks it against rotation by the action of the drive spring 8, when 'the drivespringiswound up. To release-the-sh'aft'from the lock spring I l, the oper ator simply exerts a pressure onthe finger grip IS in a direction to unwind said spring, wherebyit releases its-grip onthe driveshaft. Such re lease -of the shaft 'from the spring I l permits 5 the -drivespringtto-momentarily drive the shaft 3 at high speed in a direction to start the engine, as indicated in Fig: 4.

To facilitate assembling the shaft and the tubua lar; handle member- 2, the wall of the tubular member may be longitudinally slotted as shown at M in Figures 1 and 2, whereby the shaft with the springs 8 and II, and the bearing collars 1,5 and 1 6 mounted thereon, may be slid into the handle member 2 from thesplit end thereof; The wall of the handle member may then be inwardly beaded or rolled as shown at l6, thereby to re-, tain-theshaft and springs in position. therein. It is to be understood that the opposite end of the handle Zmay be similarly inwardly beaded or rolled as shown at' IT, wherebythe bearing 001-. lars iand 6 will-engage the inwardly rolled portions Sand 1'! and thereby prevent relative axial, movement" of the shaft within the handle.

Another important feature of" the invention resides in the means provided at the forward end of the shaft3 for axially-aligning the shaft with the propellenbest shown in Figure 1, a cupshaped member [8 in the form of a coiled spring isjse.-'

cured to the shaft and is designed to fit overthe,

hub or center portion of the propeller; By constructing the socket member 18 in the form of a coiled spring it may lightly engage the propeller when the device is held in operative engagement therewith, and its yieldability also permits it to readily adapt itself to variations in the shapes of hubs of various forms'and sizes of propellers.

Another important feature of the invention resides in the unique construction and mounting of the driving means provided on the drive shaft 3 fonengaging and rotating, a propeilen-when the drive shaft is released. As clearly illustrated in the drawing, to thus drivingly connect the drive shaft 3 to the propeller, the drive shaft is shown proyidedj at' its forward end with opposed studs or, arms lileach having a normally forwardly extendingdrive element 21 pivotally mounted thereon.- The: elements 2! are mounted for independent pivotal movement, and to provide adequate-bearing supports therefore, each is shown comprising a piece of wire provided with a loop Figure 1.

In the operation of the device, the socketxmem-.

ber l8 provided at one end'of the driveLshaftS isl; engaged with the hub of the propeller -or engine: I shaft, whereby thedrive elements 21 ar'e nor w mally positioned to engage the trailing edges of the propeller blades,- as indicated inFigure li Before engagingthe starting devicewith2'the propeller, it is-to be-understood that thewspringf 8 has been wound up by relatively rotating the drive shaft 3 with respect to the tubular-supporh When the startingdevice has:- been applied'to the propeller; as shown in Figure:

ing member 2;

applies avslight pressure E3 of the lock spring-4 I,

1, the operator simply against-the finger grip whereupon the'drive shaft 3 is suddenly ieleasedz Such sudden release of the drive shaft'will causa thedrive fingers 2! to engage and momentarily drive thepropeller at high speed whereupon "the engine is started. As-soon asthe engine'is started-"*- and the propeller over-runs the drive-elements 2 I,"

should the-operator fail to remove the starting device from the propeller no harm is done-as the advancing propeller blades will engage-the- Other-sides of the drive elements '21 'and" swing I them'out of'the path thereof-l The' tension in the spring 2 5, as hereinbeforestated, is very light, 1

whereby engagement of the propeller bladeswiththe opposite sides of the-drive elements or fingers 2|, as shown inFigure 5; will have littleor moretarding action upon the propeller when the lat ter is started bythe sudden-startingof the engine. The device is extremely simple and inexpen sive in-construction and is very light and compactwhereby it may be conveniently carried" in fa pocket; if so desired. Iii-providesapositive'start ing device for miniature' engines because of "the;

high speed momentarily imparted to the'propek ler' and-engine when-thedrive spring isreleasedif' It will also benoted that-because of the'drivefi' spring 8ihavinga driving connection withtl'iej"' shaft 3 through friction, thereis no danger'ofi" over-loading thedrivetspring as, aresult of exyi cessive unwinding. When the spring' 'has been, I unwound to, a predetermined degree',"theijreduced end thereof which frictionally engages the drive shaft will relatively open or increase in diameter, thereby causing the shaft to slip or ,free wheel thereby preventing damage to the parts and providing an additional safety feature.

In Figures 6 and '7 there is shown a modified form of driving connection shaft 3 and propeller drive fingers or arms 2|. As here shown the drive elements 2| are carried by a ratchet wheel 26 rotatably mounted on one end of the shaft 3 and driven therefrom through a small spring actuated dog 21 carried by an arm 28 secured to the shaft. By this arrangement when the drive shaft 3 is released to impart rotation to thepropeller through the drive fingers 2|, the drive fingers may be driven by the propeller blades independently of the shaft 3 in the direction indicated by the arrow inFig- -ure 7, as a result of the ratchet drive between the shaft and drive fingers.

In Figures 8 and 9 a similar form of driving connection is provided between the drive shaft 3 and drive finger 2|. In this form, the drive fingers are carried by a short shaft 29 shown rotatably mounted in one end of the drive shaft 3 and carrying a clutch element 3| adapted to be driven by a complementary clutch element 32 secured to the shaft 3. of conventional and .well known roller or ball type clutches which may be utilized for this purpose. A well known form is indicated in Figure 9.

between the drive There are numerous forms a The present invention provides a device wherev by a motor of the class described may be quickly started without engaging the propeller blades with the fingers. It has suificient power to start most such engines at the first attempt, and thus eliminates the use of auxiliary or booster batteries, such as are frequently utilized for starting airplane engines of this general type.

As shown in the drawings, the drive fingers or elements 2| are preferably encased in rubber or some other suitable material whereby they can not damage the blades of the propeller when starting the engine, and when the propeller overruns the rotation of the drive fingers,-and its blades engage the opposite sides thereof, as shown in Figure 5.

As many apparently widely different embodi-' ments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself. to-

the specific embodiments herein except as defined by the appended claims.

I claim as my invention:

I. In a starter for miniature airplane engines, a drive shaft having means atone end for aligning it with an engine crank shaft and a propeller secured thereto, an element mounted for relative pivotal movement on the drive shaft about an axis disposed transversely thereto, means forpreventing pivotal movement of said element in one direction whereby when the starter is opera tively applied tothe engine crank shaft or the hub of the propeller and the drive shaft is operated, said element will engage and rotate the propeller to start the engine, said element being swingable in the opposite direction to permit unrestricted rotary movement of the propeller when the engine starts.

2. In a starting device for miniature airplane engines, a drive shaft having means at one end for aligning it with an engine crank shaft and a propeller secured thereto, an element mounted for relative pivotal movement on the drive shaft about an axis disposed transversely thereto, stop means for preventing pivotal movement of said element in one direction, spring means normally holding said element against said stop means whereby when the starter is operatively applied to the engine crank shaft or the hub of the propeller, said element will be positioned to engage and rotate the propeller to start the engine, said element being swingable in the opposite direction to permit unrestricted rotary movement of the propeller when the engine starts.

3. In a starter for miniature airplane engines, a drive shaft having means at one end for aligning it with an engine crank shaft and a propeller secured thereto, spaced elements mounted for relative pivotal movement on the drive shaft about an axis disposed transversely thereto, stop means for preventing pivotal movement of said elements in one direction whereby when the starter is operatively applied to the engine crank shaft or the hub of the propeller and the drive shaft is operated, said elements will engage and rotate the propeller to start the engine, said elements being readily swingable in the opposite direction to permit unrestricted rotary movement of the propeller when the engine starts.

4. In a starter for miniature airplane engines, a drive shaft having means at one end for engaging the hub of a propeller to axially align the drive shaft with the propeller, spring-actuated elements carried by the drive shaft and adapted for pivotal movement thereon about an axis disposed crosswise of the drive shaft, said elements normally being positioned in the path of the propeller blades when the device is operatively engaged with the propeller hub, means for rotating the drive shaft whereby said elements will engage and rotate the propeller to start the engine, and the pivotal mounting of said elements permitting the propeller blades to move said elements out of their path when the engine starts and the speed of the propeller exceeds the speed of the drive shaft.

5. In a starter for miniature airplane engines, a supporting member, a spring-wound shaft in the supporting member, means for locking the shaft to the supporting member in energy-storing position, means at one end of the shaft for axially aligning it with the propeller, a pair of springactuated propeller drive elements carried by the drive shaft and disposed in diametrically opposed relation thereto, stop means for preventing pivotal movement of said elements in one direction whereby they may engage and impart rotary movement to the propeller when the drive shaft is' released, and spring means normally retaining said elements against said stop means and permitting said elements to be swung out of driving engagement with the propeller blades by said blades, when the engine is started.

6. In a starter for miniature airplane engines, a drive shaft having means at one end for aligning it with the propeller, a tubular member rotatably supporting said shaft and providing a handle for the device, a spring within the tubular member having one end fixed thereto and its opposite end drivingly connected to the drive shaft whereby said shaft may be rotated to store up power in said spring, means for retaining the drive shaft in spring-wound position, springactuated elements carried by the shaft andv entree -diriefetion"jiviieielwfwherr the js'tarter" is; app'iiee to V andthe'drive shaft is released,

airlengine crank shaft" and a propeller mounted thereon, a tubular member rotatably supporting :saidshaft and providing a handle, f or} the device, adrive spring within the tubular member having one-en fixed to the drive shaitand'havingits opp" ite end'drivingly connected to the drive :shaitf whereby said shaft maybe rotated to store 111' power in the spring, means for retaining-the drive 11mm sprin'g wound' position, a pair of zspri glactuated elements carried by the drive :shait' and mounted for pivotal movement thereon :about an axis disposed crosswise of the drive;

:shaft whereby said elements will be positioned between the propeller blades when the starter is :applied to the propeller, and means whereby the :shaft retaining means may be actuated to release the drive shaft, whereupon the shaft is momentarily rotated by said spring to thereby impart rotary movement to the propeller through said yieldably mounted elements, the pivotal movement of said elements permitting the propeller blades to move said elements out of their path when the engine starts and the speed of the propeller exceeds the speed of the starter drive shaft.

8. In a starter of the class described, a drive shaft provided at one end with a centering socket adapted to receive one end of an engine crank shaft or the hub of a propeller mounted thereon thereby to axially align the drive shaft with the propeller, a tubular member enclosing the major portion of the drive shaft and providing a handle for the starter, a drive spring mounted within the tubular member and having one end anchored thereto and its opposite end having a driving connection with the drive shaft, a spring-operated device for locking the drive shaft against relative rotation in the tubular member when the drive spring is wound up, laterally extending arms on said shaft, and a pair of propeller engaging elements mounted for pivotal movement on said arms and having springs normally retaining them in driving positions with respect to the propeller blades when the starter is operatively applied to the engine shaft or propeller, said elements lee-- ing adapted for pivotal movement about the axes of said arms in a direction to permit the propeller blades to engage and move said elements out of their path, when the engine starts and the speed of the propeller exceeds the speed of the starter drive shaft.

9. In a starter of the class described, a drive shaft provided at one end with a yieldable sen-'- tering socket adapted to receive the end 'of the engine crank shaft or the hub of apropeller lments Willehgage the, propeller blades dri enciissni ne ma o-r oft oa olf theoviding a handlef i e ie io g e blades the sta I the prepener; the pivdtalmoan ments permitting them atriot the prep-'e1ier'b1ede 'by saiabiades; when the ngirie' is sudd'enly' started-and the sp'eeaof: the propeller exceeds drive-shaft;

1'0; In a-st'arter of the classdescrlbed ,=a tiibularsupporting member; a drive: shait rotatably mounted insaid membea asprin'ghaving onelend secured? to" the i drive shaft and its opposite end: secured: towsaidtubularmember whereby when the shaft? is rel'ati vely rotated in one: direction in said member} the spring isIWOllIldWlti to condition:

it for subsequently momentarily. driving the shaft, means for locking-1 the drive" shaft against relative rotation-insaid tubularmember, a manually operable control device for releasingsaid locking means; a 'centering devices'ecured'to; the shaft for axially aligning thedrive shaft withthe propellerand-engine crank shaft;. drive elements carried by the drive shaftandadaptedfor: pivotal movee; went about" an axis disposedat right angles to the drive shaft whereby'whene the device is op-i; era-tively applied to the hub of a propeller, pree para toryto starting the engine, said; elements will be. positionedhetweenthe prope r 'wheree by when theengine drive-shaft "is released, said 'elenf ente'willeneaee th pro ellerblad sand roe tate the propeller to start the engine, and-means permitting. the-propeller blades -tornove-:s aid elemerits; o t'zoi: hei ,path v en-thesp d of th l propeller ex eeds-th speed oft estert rr ve Sh ft? i i c ine-Oman STREED; REFERENCES CITED The followingre'ferences areofrecord in the file of thlspatent:

Ni' ED" TA ES PA E S mime-er Name Date 1,337,113 1' Bond Apr.p-l3,- 1920, 1,620,998" Mar. l5, 1927 2,385,;963

FOREIGN" P TENTS Number Country Date a 193,961 Great Britain Mar. 1, 192 3 i ii i ytfi shaft witl-r theipropeller a-tubulair membere tw t6 be meted out et the the speed of 1 the starters

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