US2343967A - Engine starter - Google Patents

Description

March 1944- J. w. FITZ GERALD 2,343,967

ENGINE STARTER Filed June 19, 1943 WW I Fyz fififleceaseo B Mary E Fi /254 1275 [mm/x c w w Patented Mar. 14, 1944 2,343,967 ENGINE STARTER John W. Fitz Gerald, deceased, late of Milwaukee, Wis., by Mary C. Fitz Gerald, executrix, Milwaukee, Wis., assignor toBriggs & Stratton Corporation, Milwaukee, Wis., a corporation of Delaware Application June 19, 1943, Serial No. 491,510

5 Claims.

This invention relates to engine starters and refers particularly to the so-called automatic type of starter wherein the pinion is automatically propelled into and out of mesh with the ring gear of an engine to be started.

It is an object of this invention to provide an engine starter of the automatic type which is entirely self-contained and requires no separate pinion stop.

As in a copending application of John W. Fitz Gerald, Serial No. 491,511, filed June 19, 1943, of which this is a continuation, it is another object of this invention to incorporate a degree of resiliency in the pinion stop and to utilize the resiliency of the resilient driving connection through which torque is transmitted from the drive shaft to the pinion for this purpose.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates one' complete example of the physical embodiment of the invention constructed in accordance with the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a view in side elevation with parts broken away and in section, illustrating an engine starter embodying this invention and showing the pinion in its normal retracted position; and

Figure 2 is a view similar to Figure 1 but with the parts in the positions they occupy when the pinion is advanced to its operative driving posi- Referring now particularly to the accompanying drawing, in which like numerals indicate like parts, the numeral 5 designates the drive shaft of an engine starter motor upon which the starter, indicated generally by the numeral 6, is mounted. The starter has a pinion 1 arranged to be moved into and out of mesh with the ring gear 8 of an engine to be started.

As is customary in starters of this type, longitudinal propulsion of the pinion to and from its operative driving position is effected by relative rotation between it and an actuator 9, the actuator being driven from the drive shaft 5 through a resilient driving connection l9.

The driving connection It) comprises a flanged drive head H adapted to be fixed to the drive shaft as by a set screw 12, a flange I3 on the actuator, and a collar 14 of rubber or other similar material having cubical elasticity confined between the flanges. A shell [5 clinched over the flange l3 and engaging over the edge of the flange l6 on the drive head holds these parts assembled with the rubber collar under a degree of precompression. v

The actuator 9, as is customary, has an externally threaded portion I'I engaging internal threads in a hub l8 projecting axially from. the pinion; and an anti-drift detent I9 yieldingly holds the pinion against creeping forwardly into mesh with the flywheel.

To the extent thus far described, the starter follows the design of previous starters of this type. Its distinction lies in the manner in which the stop for the pinion is provided.

To this end the pinion is rigidly secured as by brazing to a tube 20. The tube 20 projects axially through and beyond the internally threaded hub I8 and is freely slidable and rotatable on the drive shaft 5. The tube 20 also passes through the actuator 9 and the resilient driving connection Ii] to project into a counterbore 2| in the drive head ll. At this point the tube has a stop 22 secured thereon in the form of a spring ring snapped into an annular groove.

The counterbore 2| is large enough to accommodate longitudinal movement of the stop 22 as the tube and pinion travel longitudinally to and from the operative driving position of the pinion. Upon reaching its operative driving position the stop 22 collides with a washer or disc 23 encircling the tube 20 and confined between the flange I6 of the drive head and the rubber collar [4. Thus as the forward propulsion of the pinion is arrested by the engagement of the stop 22 with the disc or washer 23, the rubber collar l4 takes up the shock and provides a degree of resiliency for the pinion stop.

Inasmuch as the transmission of torque through the resilient drive connection requires a torque transmitting connection between the drive head and the rubber collar, the washer or disc 23 is nonrotatably but longitudinally movably connected to the drive head as by tongues 24 on the periphery of the Washer or disc engaging in slots 25 in the flange l6.

From the foregoing description, taken in connection with the accompanying drawing, it will be readily apparent to those skilled in the art that this invention provides a simple and highly ed engagement with the internally threaded hub of the. pinion so that relative rotation between said parts propels the pinion and the tube loneitudin-ally with respect to the actuator; a'drive head securable to the starter motor shaft; a resilient driving connection between the drive head and the actuator including a part in juxtaposition to the tube; and a stop on the tube adapted to collide with said part to limit axial movement of the pinion in one direction. I

. 2. In an engine starter: a pinion; a tube fixed to the pinion and projecting axially therefrom, said tube being adapted to be slidably mounted on the shaft of a starter motor; means for propelling the pinion and the tube axially along the motor shaft and for imparting driving torque to the pinion, said means. including a resilient driving connection encirclingthe tube and having a driving head adapted for securement to the motor shaft, part of the resilient driving connection being in juxtaposition to the tube; and

a'stop' on the tube adapted to collide with said part when the pinion reaches its operative driving position.

3. In an engine starter: a pinion adapted for longitudinal movement along and rotary movement with the shaft of a starter motor; a pinion actuator; a connection between the actuator and the pinion whereby relative rotation between said parts propels the pinion longitudinally to and from an operative driving position; a drive head adapted to be fixed to the shaft of the starter motor; a resilientdriving connection between the actuator and the drive head including a part nonrotatably but axially movably connected with the drive head, and a body of elastically deform-able material between said part and the actuator; a tube fixed to the pinion and freely slidably projecting through the actuator one direction.

and the resilient driving connection and adapted to be slidably mounted on the shaft of the starter motor; and a stop on the tube adapted to collide with said part of the resilient drivin connection which is nonrotatably but axially movably connected to the drive head to limit longitudinal movement of the pinion in the directionto define its operative driving position.

4. In an engine starter: a tube adapted to be slidably and freely rotatably mounted on a drive shaft; a pinion fixed to the tube so that the pinion and tube move in unison, said tube projecting axially from the pinion; a drive head adapted to be fixed to the drive shaft and having a part telescoped over one end portion of the tube; a resilient driving connection between the drive head and the pinion encircling the tube and by. which the pinion is propelled longitudinally to and from its operative driving position and torque is transmitted from the drive head to the pinion; a pinion stop fixed to the end partion of the tube which is telescoped within the drive head; and an abutment forming part of the resilient driving connection and in position to be engaged by the pinion stop to limit longitudinal movement of the tube and pinion and define the operative driving position of the pinion.

5. In an engine starter: a tube adapted to be slidably and rotatably mounted on a drive shaft;

of the pinion is transmitted to the tube and the pinion and tube move in unison; a drive head adapted to be secured to the drive shaft; a resilient'driving connection between the drive head and the pinion by which the pinion is propelled longitudinally to and from its operative driving position and through which driving torque is resiliently transmitted to the pinion when in its driving position, said resilient driving connection encircling the tube and including a body of elastically deformable material; a stop on the tube; and an abutment supported by the body of elastically deformable material and in position to be engaged by said stop to limit longitudinal movement of the pinion and tube in MARY C. FITZ GERALD, Executria: of the Estate of John W. Fitz Gerald,

Deceased.

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