US3000471A - Spring brake for gasoline engine starter - Google Patents

Description

Sept. 19, 1961 R. A. GLENN SPRING BRAKE FOR GASOLINE ENGINE STARTER Filed April 10. 1959 WEA/TOR:

RICHARD A. GLENN IIIIIIIIHII l'ATOp/VEV Fic. 3

3,000,471 SPRWG BRAKE FOR GASOLHQE ENGINE STARTER Richard A. Glenn, Racine, Wis., assignor, by mesne assignments, to Peter Vakos, Racine, Wis. Filed Apr. 10, 1959, Ser. No. 805,441 4 Claims. (Cl. 18S-82.6)

This invention relates to a gasoline engine starter, and, more especially, it relates to a free-motion brake for an engine starter. This is a continuation-impart of U.S. application Serial No. 776,106, led November 24, 1958, now Patene No. 2,955,584.

In the construction of starters for small gasoline engines, such as the lawn mower and outboard motor type, it is now common to employ a spring-impulse type of starter. These starters generally operate to have the spring wound in the direction reverse to the running direction of the engine, and, upon release of the springs energy, the engine will be cranked in its running direction. In this action, the present invention is concerned with the braking action required on the spring after it is Wound and prior to the release of it; and it is also concerned with engagement of the starter with the engine crankshaft prior to release of the spring.

Accordingly, it is an object of this invention to provide a brake in an engine starter whereby the starter spring will be securely retained against unwinding prior to the desired time of release.

Still another and more comprehensive object of this invention is to accomplish the foregoing object in conjunction with a provision in the braking action to cause the starter to engage the crankshaft before the energy of the spring is released. In this feature, the spring energy is not impacted against the crankshaft, but rather it is fully applied thereagainst without impact.

Still another object is to provide an engine starter which is automatic in the re-setting of the parts to the position for winding, to provide automatic disengagement of starter from engine after the engine is running, and to provide that no exterior starter parts rotate in response to release of the springs energy.

Other objects and advantages will become apparent upon reading the following description in conjunction with the accompanying drawings, wherein:

FIG. 1 is a sectional view through a preferred embodiment of this invention and showing the same mounted on a fragment of a conventional gasoline engine.

FIG. 2 is a sectional view taken along the line 2 2 of FIG. 1.

FIG. 3 is a side view of parts shown in FIG. l.

FIG. 4 is a top view of FIG. 3.

The same reference numerals refer to the same parts throughout the several views.

FIG. 1 shows the starter of this invention to be mounted on a conventional type of gasoline engine having a housing portion 11 and a crankshaft end 12 to which is attached, as by nut 13, a ring or ratchet member 14 having internal teeth 16. Also, a grass clipping guard or deflector 17 is secured to the cup-shaped ring 14 to protect the interior of the gasoline engine from debris of grass clippings or the like.

te States Patentl O The starter includes a housing 18 which is supported r'f'lce Y ceive nuts 26. A shaft 27 is rotatable Within the housing 18 and extends above and below the housing and is coaxial With the axis of the crankshaft 12. A sleeve or part of a brake member 28 is concentrically disposed over the shaft 27 and is attached to a handle 29 by means of a bolt 31 which passes through the handle and into a threaded upper end of the sleeve 28. At this time it should also be noticed that the handle 29 is preferably made of a channel-shaped material and includes a hinge 32 for purposes of folding the handle back into an inoperative position, as shown in FIG. 1, when the handle is not required for operating the starter. The sleeve 28 has a pin 33 extending therethrough and connecting to a collar 34 by extending into the collar so that the sleeve 28 and collar 34 are nonrotatably secured -together such that the rotation of one imparts identical rotation to the other. A member 36 is coiled around the circular collar 34 in the several coils shown, and the member is of suitable material so that, through a pin 37, depending from the handle 29 and with the pin engaging a loop 38 on the upper end of the member 36, the latter is placed in a rotationally driving condition with respect to the collar 34 when the handle 29 is rotated in a counter-clockwise direction, as viewed from the top. In reverse, the member 36 will not tighten upon the collar 34, and thus there will be no drive connection between the member 36 and the collar 34. In this manner, the member 36 is a unidirectional drive connector or sprag which impar-ts rotation therethrough in only one selected direction, namely the counter-clockwise direction in the instance shown.

The lower end of the sleeve 28 is engaged with a pin or rod 39 extending through the shaft 27 and is disposed in the diametrical slot 41 in the lower end of the sleeve 28. On the lower end of the sleeve 28 there is a spiral coiled spring 40 shown Wrapped approximately one and one-half times around the sleeve 28. A looped end 42 of the spring 40 receives the pin 44 which is welded to the housing 18. The opposite end of the spring has an offset or indentation 43, shown in FIG. 4, and the end 43 engages slanted teeth 45 formed on the sleeve 28. The teeth are thus slanted to allow the sleeve 28 to rotate in the B direction but not in the reverse direction. Thus, spring 40 is wound opposite to the member 36 so that rotation of the handle 29 in the B direction will tranmit the rotation to the sleeve 28, and spring 40 will merely be in sliding contact with the lower portion of the sleeve 28. However, when A direction rotation of the sleeve 28 is made, such as that which might be induced by the shaft 27, then the spring 40 will prevent the sleeve 28 from rotation in the clockwise direction, as viewed from the top, as the spring tightens up on itself.

At this time it should also be noticed that a member 46 is stationarily attached to the cover 23, and the member has an inclined upper surface 47 thereon, and this surface engages a similarly inclined surface which is the lower edge of the circular member 48 rotatably disposed over the central portion of the sleeve 28. A projection 49 is attached to the member 48, and a control rod 51 is in turn attached to the member 49 with the latter being secured to the member 48 by welding or the like. A clamp 52 is mounted on the housing 18 ina suitable manner to support the conduit 50 so that the rod 51 can moveaxially through the conduit 50 to rotate the member 48. It should also be understood that the rod 51 extends to a position remote from the housing 18 such as to the upper end of a lawn mower handle so that the starter can be controlled from a remote point. Thus, upon axial movement of the rod 51, the member 48 is rotated to move its lower surface up the incline 47 of the member 46, and

73 of the support 63.

such movement raises the collar 34 and the sleeve 28 to disengage the sleeve groove 41 from the pin 39 and thus free the shaft 27 from the connections described in the foregoing. In order to maintain the connection between the shaft 27 andthe sleeve 28, a ilatspring 53 is ,disposed between the housing cover 23 and the shoulder .54 of the sleeve 28 so that the spring 53 yieldingly urges downwardly on the sleeve 28 and on the spring 42 to maintain the sleeve and shaft engagement mentioned, and to keep the spring 42 on the lower end of the sleeve 28, as shown.

It wil-l also be noticed that a spirally coiled spring 56 is disposed within the housing 18 and connected to a stud 24 at the left side in FIG. 1 at the outer end of the spring while the inner end of the spring is connected to ya sleeve 57 which is preferably iiat as at 58. The spring is coiled in a clockwise direction from inside outwardly as viewed from above, and this direction is opposite to that of the spring 40. A pin 59 extends through the shaft 27 and sleeve 57.

The lower end of the shaft 27 is supported by a circular housing portion 63 which is welded to or otherwise made integral with the floor of the housing, las shown. The shaft lower end has a member 64 secured thereto by means of the bolt 66 so that the member 64 rotates with the shaft 27. A pawl member 67 is attached to the member 64 through a pivot pin 68 which is anchored to the U-shaped portion 69 of the pawl member 67. The pawl 67 also includes an arm71 which extends around shaft 27 to a side diametrically opposite the pivot pin 68, and the end of the arm 71 carries a friction or rubber member 72 which extends upwardly in FIG. l to engage the bottom In this manner, the member 72 is a drag connector between the pawl 67 and the housing. Another portion 74 of the pawl 67 extends to the outermost limit of the pawl 67 and is adjacent the teeth 16 of the ring 14. It will thus be understood that when the shaft 27 is rotated in the clockwise direction, which is the direction indicated by the arrow marked A, then the drag-member 72 engaging the surface 73 will pivot the pawl 67 about its Ypin 68 so that the end 74 will engage the teeth 16. At this time it should also be understood that the spring 4t) has been diametrically expanded during the wind up, and, upon release of the handle 29, the spring 40 again contracts to the snug position shown in the drawings. Thus there is slight rotation of thershaft 27 to cause the portion 74 of the pawl 67 to engage the ring teeth 16 as the spring 40 contracts. Thus, the pawl and the ring are engaged prior to the time that the full energy of the spring 56 is released to transmit rotation to the shaft 27 and subsequently to the engine crankshaft 12 for starting the engine. A return tension spring 76 is connected between a looped member 77 attached to the ange member 64 at one end of the member 77 while the other end thereof secures the spring '76. The latter is then also attached to the portion 77 of the pawl 67 to urge the pawl radially inward for disengaging the portion 74 from the teeth 16. When the engine commences to operate, the crankshaft 12 with the member 14 will rotate at a high speed so that the teeth 16 free the pawl 74 which can return to the FIG. 2 position under the influence of the spring 76. Thus, no part of the starter continues to rotate when the engine is running. Also, the starter is so constructed that it can be wound up even while the engine is running.

While a speciiic embodiment of this invention has been shown and described, it should be obvious that certain changes could be made therein, and the scope of this invention, should, therefore be limited only by the appended claims.

What is claimed is:

1. A free motion brake for use on a gasoline engine starter of the spring impulse type, comprising a rotatable member, teeth on the periphery of said member, a `spiral coiled spring disposed over said teeth and having the outer end thereof anchored in a iixed position, an indentation in the length of the other end of said spring and extending radially inwardly between two of said teeth to be engaged with said teeth, said spring being coiled inwardly from said outer end and being overlapped upon itself over said indentation for expanding to loosen on said teeth when the latter are rotated in the direction opposite to said coiled direction, and for said spring contracting to tighten onto said teeth when the latter are rotated in said coiled direction and after a slight rotation thereof.

2. A free motion brake for use on a gasoline engine starter of the spring impulse type, comprising a member rotatably and axially movably mountable in said starter, teeth on the periphery of said member, a spiral coiled spring disposed over said teeth and overlapped thereon and having the outer end of said spring attached to said starter to be movable axially thereof, an offset on the other end of said spring and engaged with said teeth, said teeth being slanted to point away from the direction of spiral of said spring from inside outwardly for expanding said spring to loosen on said teeth when the latter are rotated in said coiled direction, and said teeth being disposed slanted for gripping said spring for contracting the latter to tighten onto said teeth when the latter are rotated in said direction opposite to the spiral and after a slight rotation of said teeth, and means connected to said member for axially moving the latter with said spring.

3. A one-way brake comprising a shaft, va sleeve axially slidably mounted on said shaft and including teeth disposed therearound and with said teeth having crests disposed in the direction of axial slidability of said sleeve, a spiral spring mounted disposed over said teeth and being overlapped on itself thereover substantially onehalf of the circumference of said sleeve at the location of said teeth, said spring including an inner end provided with an indentation in the length thereof and being radially inwardly directed with respect to said sleeve and being biased into engagement with said teeth by the overlapping portion of said spring, the opposite end of said spring being anchored for causing said spring to tighten upon itself in one direction of rotation of said sleeve for restraining said sleeve against -rotation in said one direction only, and means attached between said shaft and said sleeve for rotating the latter two together and for releasing said sleeve from said shaft upon axial shifting of said sleeve.

4. A brake for restraining rotation of apparatus in one directiononly, comprising a member including teeth circularly disposed therearound and being tangentially slanted toward said one direction, a spring spiralled around said teeth from outside inwardly in said one direction and partly overlapped on itself and on said teeth and biased into engagement with said teeth, the radially inner end of said spring including an olset disposed between said teeth, the other end of said spring being anchored for causing said spring to tighten on said teeth upon rotation of said member in said one direction` for restraining said member against rotation in said one direction.

References Cited in the le of this patent UNITED STATES PATENTS 1,847,867 Dodge Mar. 1, 1932 1,852,174 Lyman et al Apr. 5, 1932 2,875,851 Vakos Mar. 3, 1959

Images