US2064670A - Starting mechanism - Google Patents

Description

Dec. 15, 1936. R R ANSlNG 2,064,670

STARTING VMECHANISM Original Filed Sept. 5, .1930

Patented Dec. 15, 1936 UNITED STARTING Raymond P. Lansing,

Eclipse Aviation Corporation,

MECHANISM Montclair, N. J., assigner to East Orange,

N. J., a corporation of New Jersey Original application September 5, 1930, Serial No. 479,993. Divided and this application August 16, 1934, Serial No. 740,177

8 Claims.

This invention relates to starting mechanism, and more particularly to inertia apparatus for starting internal combustion engines.

An object of the present invention is toy pro- Vide starting apparatus of the inertia type which is so constituted that the inertia member may be more easily brought up to the desired speed of rotation.

Another object of the invention is to provide, in an inertia starter, an inertia mass having a variable moment of inertia.

Another object of this invention is to provide a manually operable inertia starter Which is so constructed that the operator will find it comparatively easy to initiate the rotation of the inertia member and bring it up to a reasonable speed.

A further object is to providean inertia member for use in starters composed of a plurality of centrifugally actuated members constituting a mass having a variable moment of inertia. The above and other objects will appear more fully hereafter in the detailed description.

One embodiment of the present invention is illustrated in the accompanying drawing, but it is to be expressly understood that the drawing is for the purposes of illustration only and is not designed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawing, wherein like reference characters refer to like parts throughout the several views,-

Fig. 1 is a side view partly in axial section and partly in elevation, with parts broken away, of a structure embodying the present invention, and

Fig. 2 is an enlarged partial sectional view taken on the line 2 2 of Fig. 1.

Referring more particularly to Fig. 1, the

starting mechanism of the present invention includes a housing constituted by an inner flanged portion 6 adapted to be secured in any suitable manner to the crank case, not shown, of yan internal combustion engine. For example, the flange of housing section 6 may be pro-vided with openings 1 to receive suitable bolts or screws (not shown) for securing the starter to the rear of the engine crank case. Attached to the outer face of the inner housing section 6, as by means of screws 8, is an'outer housing section 9 provided with a laterally extending portion 9a,v (Fig. 2) on which is mounted a casing I0 provided with a cover II constituting a housing for an inertia mass l2.

Energy may be stored in the inertia mass I2 by rotating the same at high speed, in a manner to be described hereafter, and this stored energy is then effective to rotate a jaw I3 adapted to be moved intov driving engagement with the jaw (Cl. 12S-179) I4 suitably attached to the engine crank shaft or an extension thereof, whereby the crank shaft will be rotated and the engine started.

Means are provided for manually rotating the The shaft I5 is adapted y with a hollow sleeve 20 drivably-attached as inv dicated by the dash-line rectangle representing flat portions on the registering surfaces of .the members 20 and 2l to the outer closed ends 2Ia of a barrel 2l. Preferably, the sleeve 20 is rotatably supported closely adjacent the bevel gear I9 by means of a ball bearing 22 suitably mounted in a web 23 provided in the outer portion of the housing section 9, and the barrel 2| is rotatably mounted in housing section 6 by means of ball bearings 24 and 25.

Rotatably mounted on the closed end 2Ia, of barrel 2l are three planetary pinions, one of which is shown in section at 26. In order to rotatably mount the pinions on the barrel there are provided three screws 28 which are threaded into the closed end of the barrel and project outwardly therefrom. Each of these screws 28 constitute a support for sleeves 21 which are pressed into counterbores in the barrel end 2m, and which may be formed integrally with an annular member 29 constituting a retainer for ball bearings 30 that surround sleeves 21 and support .the pinions. The latter are spaced degrees apart around the closed end of the barrel and mesh with a surrounding internal gear 3| which is pinned or attached in any other suitable manner to the housing section 6.

Each of the planetary pinions 26 is also in mesh with a sun gear 32 that is rotatably mounted on the inner end of sleeve 20 by means of a roller bearing 32a. Formed integrally with the sun gear 32 is a large spur gear 33 which meshes with a pinion 34 rotatably mounted on a shaft 35 that is positioned in the extending portion 9arof the outer housing section at a distance from and parallel to the hollow sleeve 20. tached to or formed integrally with the pinion 34 is a crown gear 36 which drivably engages a pinion 31 drivably secured to a shaft 38 that carries the inertia mass I2. The upper and lower ends of shaft 38 are rotatably mounted in the housing I0 by means of ball bearings 39 and 40, whereby the inertia mass to be described more fully hereafter is maintained supported in operative position.

Rotation of cranking shaft I5 is transmitted Rigidly at- Y.

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through bevel gears I8 and I9, sleeve 20, barrel 2l, planetary pinions 26, sun gear 32, spur gear 33, pinion 34, crown gear 36 and pinion 31 to rotate shaft 38. In view of this step-up train of gearing it will be apparent that one revolution of the cranking shaft I5 will result in a very large number of revolutions of the shaft 3S and if the latter offers any substantial resistance to rotation it will be extremely diiiicult for the operator to actuate the cranking shaft I5.

In starters of the inertia type heretofore provided the inertia member has been constituted by a solid mass having a constant moment of inertia, or radius of gyration, and While relatively small in Weight, this mass offers a considerable amount of resistance to rotation due to the stepup gear train employed. In accordance with the present invention there is provided an inertia mass having a variable moment of inertia, the moment of inertia being relatively low when shaft 38 is rotated at low speed and increasing as the speed of rotation of shaft 38 is increased, whereby less effort is required to place said mass in rotation.

In the form shown, the inertia mass is constituted by four, substantially parallel segments 4|, which in normal position constitute a substantially hollow thick walled cylinder of small diameter. Intermediate the ends of the inner face of each segment is secured a resilient member 42 which may be constituted by a piece of clockspring that is disposed parallel to shaft 38 and is secured at its upper end in any convenient manner, as by means of a suitable sleeve 43, to said shaft. The lower end of each of the resilient members 42 is secured to a sleeve 44 which slidably surrounds the lower reduced portion of shaft 38. A shoulder 38a formed on said shaft constitutes a stop for limiting upward movement of sleeve 44 relative to the shaft.

When slow speed rotation is imparted to shaft 38 through the train of gearing described above, the segments 4| are retained by springs 42 closely adjacent and surrounding the shaft 38. Consequently the moment of inertia of the mass constituted by the segments 4| is low and the resistance to rotation is relatively small. As the operator increases the speed of rotation of shaft 38, the segments 4I move radially under centrifugal force until they assume a position closely adjacent the inner walls of housing Ill as indicated in dotted lines in Fig. 4. As the segments move outwardly the moment of inertia increases and consequently the effort on the part of the operator must be increased, but since the cranking shaft is now revolving and since he has not greatly exerted himself in bringing the cranking shaft to this speed of rotation, he is enabled to readily exert the extra effort required to increase the speed of rotation of shaft 33. When the cranking shaft is rotated at vapproximately 8G R. P. M. for example, suiiicient energy will be stored in the inertia member or flywheel constituted by elements 4| to start the engine.

It will be apparent that when the operator ceases to exert a force on the cranking shaft after bringing the flywheel up to the desired speed of rotation, the latter is effective to rotate the jaw I3 through the gear train and barrel 2| previously described. Yielding means are preferably interposed between the barrel and jaw i3, so that the gearing is at all times protected against excessive loads. In the form shown the yielding means is constituted by a multiple disk clutch comprising a plurality of annular friction disks 45 which are splined to the inner surface of the barrel closely adjacent the end 2| a thereof. In interleaving relation with the disks 45 are a plurality of disks 46 which are splined to an inte- `riorly threaded nut 41 provided with a flange 41a which engages an annular plate 48 which is L-shaped in cross section, said plate being interposed between the friction disks and the flange 41a. In engagement with the inner face of the Bange are a plurality of coil springs 49 Whichbear at their inner ends against an adjusting nut 53 threaded into the open end of barrel 2|. By adjusting the position of the nut 50, the tension of the springs on flange 41 may be varied, thereby varying the frctional engagement of the disks 45 and 4E, whereby the amount of torque transmitted by said friction clutch may be varied.

Threaded into the nut 41 is a hollow shaft 5| provided on its outer end with a stop nut 52 adapted to positively limit movement of said shaft inwardly relative to nut 41. The inner end of shaft 5| is longitudinally splined on the outer surface thereof to engage corresponding splines formed in the laterally extending hub portion |3a of the jaw I3. Longitudinal movement 0f jaw I3 relative to shaft 5I is permitted by the splined connection between these elements.

Normally, the jaw I3 is out of mesh with jaw I4 and means are provided for yieldingly retaining said jaw I3 in this position, said means also being adapted to assist in moving the jaw I3 into meshing engagement with jaw I4 whereby the energy of the flywheel may be imparted to the engine to start the latter. In the form shown said means includes a rod 53Vwhich slidably extends through sleeve 20 and shaft 5|, the outer end of said rod terminating closely adjacent a vertical plane through the longitudinal axis of cranking shaft I5 and the inner end of said rod terminating closely adjacent the inner face of web |3b constituting a portion of the hub of jaw I3. Intermediate its ends rod 53 is provided with a shoulder 53a which normally abuts against the outer end of the threaded shaft 5I. receive a nut 54 which bears against the face of web |32) and thus retains jaw I3 in operative engagement with said rod. A coil spring 55 surrounds rod 53 and the outer end of said spring extends into a pocket formed in the inner end of threaded shaft 5| while the opposite end of said spring bears against a pair of washers 56 which engage the face of web I3b and prevent seepage of oil from the engine crank case past the opening in said web. Spring 55 yieldingly resists movement of jaw I3 toward the shaft 5|.

Manually operable means (not shown) may be provided whereby rod 53 will be moved to the left, as viewed in Fig. 1, whereupon shoulder 53a moves threaded shaft 5| to the left relative to shaft with nut 41. Preferably, a coil spring (not shown) is provided for maintaining rod 53 in normal position and if the energy of the ywheel is expended without starting the engine the jaw I3 will be automatically retracted by the action The inner end of rod 53 is threaded tor of said spring on rod 53. As soon as the engine starts the inclined faces of the teeth of jaws I3 and I4 are effective to move jaw I3 to the right as viewed in Fig. 1.

The operation of the device is as follows: The operator engages the hand crank with the cranking shaft I5 and with comparatively little effort is enabled to rotate the flywheel through the train of gearing, since the moment of inertia of the mass I2 is small and hence offers only a small amount of resistance to rotation. As the speed of rotation of shaft 38 is increased, the sectors 4I move radially, sleeve 44 sliding -up shaft 38 until it abuts against shoulder 38a. The radial movement of the sectors 4I increases the moment of inertia of the` mass I2 and hence the effort that must be exerted by the operator, but the parts are now moving and the additional work is easily performed in view of the fact that he has been able to bring the flywheel to a reasonable speed Without an unusual amount of effort. As soon as the flywheel has been brought up to the desired speed of rotation, i. e., when sufficient energy has been stored in the flywheel, the operator actuates bell crank lever 51 to move jaw I3 into driving engagement with jaw I4 and the energy of the flywheel is now effective to crank the engine.

Since the parts of the engine are stationary at the instant that jaw I3 is moved intoengagement with jaw I4, said parts offer an enormous amount of resistance to the elements of the starter. The friction clutch, however, permits a certain amount of slippage between jaw I3 and barrel 2| so that no damage can result to the starter elements. As the parts of the engine are brought up to speed the slippage in the clutch decreases until all of the parts move in unison and the engine is started.

' The over-running action of jaw I4 is now effective to disengage jaws I3 and I4 and the parts of the starter are returned to normal position.

The parts are so assembled and constructed as to be light in weight and positive in action. Yielding means are interposed between the starter jaw and the gearing whereby said gearing is protected against injury due to backres or unusual operating conditions. In the form illustrated the device is adapted to be manually actuated only, but it will be readily understood by those skilled in the art that electrical actuating means may be combined with the mechanism illustrated where desirable.

Various changes may be made in the details of construction and arrangement of parts as will be readily apparent to those skilled in the arIt. Reference will therefore be had to the appended claims for a definition of the limits of the invention.

This application is a division of my application 479,993, filed September 5, 1930.

What I claim is:

l. In starting apparatus of the class described an inertia mass comprising a plurality of substantially parallel segments, means for rotating said segments about a common axis, said rotating means comprising a shaft whose axis coincides with said first named axis, a second shaft constituting part of the apparatus to be started, means for rotating said first named shaft and thereby developing centrifugal force applicable to said parallel segments to store energy therein for subsequent transfer to said second shaft, and means for maintaining the centers of mass of said parallel segments in fixed angular relationship during operation of said rotating means.

2. In starting apparatus of the class described, a shaft to be rotated, and means for starting said shaft in rotation, said starting means comprising a second shaft, a sleeve movably mounted on said second shaft, a plurality of yielding members, each having one end attached to said second shaft and the opposite end attached to said sleeve, a segment attached to each of said resilent members intermediate the ends of the latter, and means for rotating said second shaft to store energy in said yielding members prior to transfer of said energy to said first named shaft.

3. In an inertia starter for internal combustion engines, the combination, with the engine crank shaft, of an inertia mass constituted solely by a plurality of centrifugally actuated members, and means for rotating said inertia mass to store energy therein for subsequent use in imparting initial rotation to said crank shaft.

4. An apparatus of the class described comprising an engine engaging driven member, a mass having a variable moment of inertia for actuating said driven member, means including a gear train operatively connected to said mass and driven member and means for actuating said gear train from the end nearest said driven member for the purpose of initially accelerating said mass.

5. A starter fo-r internal combustion engines, comprising, in combination, a driven member adapted for rotary and longitudinal movement, a mass having a variable moment of inertia for actuating the driven member, means including a yielding driving connection for drivably connecting said mass with the driven member, manually operable means for rotating said mass whereby the moment of inertia of the same increases to a. maximum prior to longitudinal movement of said driven member, and means for positively moving the driven member longitudinally.

6. An inertia starter for internal combustion engines comprising an engine engaging driven member adapted for rotary and longitudinal movement, a mass comprising a plurality of centrifugally actuated elements for rotating said driven member, motion reducing means drivably connected to said mass and driven member, means for rotating said mass whereby the moment of inertia of the same reaches a maximum value, and means for thereafter moving the driven member to engaging position.

7. In starting apparatus of the class described, a rotatably mounted inertia mass having a variable moment of inertia, a cranking shaft, and gearing operatively connected to said shaft and mass whereby energy may be stored in the latter, the moment of inertia of said mass being relatively low at low speed.

8. The method of utilizing an inertia mass as an engine starting agency, which comprises accelerating the mass and at the same time increasing its moment of inertia, then decreasing its moment of inertia as it delivers its stored energy to the engine to be started.

RAYMOND P. LANSING.

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