US1883417A - Engine starter - Google Patents

Description

Oct. 18, 1932. Y. SEKELLA 1,883,417

'ENGINE STARTER Filed May 2, 1931 v 11v VENTOR yams/tow 'S e/caLLQ/ BY A TTORNEY Patented Oct. 18, 1932 {UNITED STATES PATENT OFFICE YOUSTON SEKELLA, OF ELMIRA, NEW YORK, ASSIGNOR TO ECLIPSE MACHINE COMPANY, OF ELMIRA, NEW YORK, A CORPORATION OF NEW YORK ENGINE STARTER Application filed May 2, 1931.

This invention relates to engine starters and more particularly to an automatic pinion shift for connecting and disconnecting a starting motor and a member such as a flywheel gear of an engine to be started.

The invention as herein disclosed is embodied in a drive of the screw shift type in which a pinion is mounted on a screw shaft driven by a starting motor, the pinion bein automatically traversed into mesh with a ywheel gear by acceleration of the starting motor, and out of mesh therewith when the engine starts.

In automatic shifts of this character the demeshing of the pinion sometimes occurs with such force that the pinion rebounds from its demeshing stop into contact with the flywheel gear. Since the latter is rotating at this time with comparatively high peripheral velocity, these attempts of the pinion to reengage are abortive and may cause unnecessary wear of the pinion or flywheel teeth.

It is an object of the present invention to provide a novel and improved automatic pinion shift which is arranged to prevent the pinion from rebounding into engagement with the flywheel gear.

Another object of the invention is to provide such a device which is arranged to gradually decelerate the demeshing motion of the pinion and frictionally dissipate its kinetic energy.

A further object is to provide such a device which performs its rebound checking function without requiring added structural elements but rather by the modification and novel method of cooperation of certain of the elements.

Further objects and advantages will be come apparent to those skilled in this art from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a side elevation partly in section of a preferred form of the present invention showing the parts in normal or idle position;

Fig. 2 is a section taken' substantially on the line 2-2 of Fig. 1;

Serial No. 534,544.

Fig. 3 is a view similar to Fig. 1 showing the parts in driving position;

Fig. 4 is a similar view showing the driving member in the position assumed when it is thrown out of engagement with the engine member;

Fig. 5 is a detail in elevation, partly brokenaway, of the actuating sleeve for the driving pinion; and

Fig. 6 is a longitudinal section of the driving pinion.

Referring first to Fig. 1 of the drawing, a power and supporting member in the form of a shaft 10 is illustrated which may be an extension of the armature shaft of a starting motor 11. The shaft 10 is smooth adjacent the motor 11, said smooth portion being bounded by a shoulder 12, formed by the enlargement of the shaft within the motor. The outer portion of said shaft is provided with spline grooves 13, and the end of the shaft is reduced and threaded as indicated at 14, providing a shoulder 15 at the ends of the spline grooves 13.

An actuating member in the form of a sleeve 16, externally threaded fora portion of its length as shown at 17 is provided with internal splines 18 (Fig. 5) adapted to env gage the spline grooves 13 of shaft 10 and is counter-bored as indicated at 19 to form a smooth bearing on the shaft 10. Positioning means for the actuating member in the form of a heavy compression spring 20 and a light compression spring 21 are mounted on the splined portion of shaft 10 the heavy spring 20 being adapted to bear against a thrust washer 22. The washer 22 is journaled on a spacing ring 23 which is' seated on the reduced portion 14 of shaft 10 against the shoulder 15, and said washer is confined in saidposition by suitable means such as a sto nut 24. The light spring 21 is adapted to ear against a second thrust washer 25 which in turn bears against the end of the actuating sleeve 16. Springs 20 and 21 are both somewhat shorter than the distance between the thrust washers 22 and 25, and spring 21 is arranged to telescope within spring 20. A connecting member in the form of a thimble 26 is arranged between the v with telescoping portions of springs 20 and 21 and is provided with an inwardly extendlng flange 27 adapted to receive the inner end of spring 21 and an outwardly extending flange 28 adapted toform a seat for the free end of spring 20, whereby the two springs are in effect connected end to end.

The thrust washer 25 extends radially beyond the spring 21 and is adapted to bear against the end flange 28 of thimble 26 after a predetermined compression of spring 21 so that further motion of thrust washer 25 in a direction to compress the springs is resisted directly by the heavy spring 20 without causing further compression of spring 21.

An abutment member for the actuating sleeve 16 in the form of a thimble 29 is adapted to be mounted on the smooth portion of shaft 10 and forms a stop for the end of the actuating sleeve. The other end of said abutment member is arranged to bear against a stop collar 32 seated on the shaft 10 in enga ement with the shoulder 12 thereof.

anti-drift thrust Washer 33 is slidably mounted on the abutment thimble 29 and is yieldabl maintained against retaining lugs 31 of sad thimble by suitable means such as a light compression spring 34., Said spring bears at one end on washer 33, and. at its other end on a flange 30 formed on thimble 29. Stop collar 32 is provided with an annular recess 35 which is adapted to receive and house the anti-drift spring 34 when the antidrift thrust washer 33 is pressed against said collar.

A driving member in the form of a pinion 37 is loosely threaded on the actuatin sleeve 16 and is adapted to be moved there y into and out of engagement with a member of the engine to be started such as a flywheel gear. Pinion 37 has a hub portion 39 extending laterall therefrom into the plane of the engine mem er 38 and into proximity to the antidrift washer 33. Pinion 37 is thus yieldably prevented from drifting into engagement the engine member 38 by the anti-drift means comprising-the spring 34 and washer 33. Motion of said pinion away from engaging position is limited by the thrust washer 25 which cooperateswith the spring 21 to form a yielding back stop for said pinion.

Theinion 37 is counter-bored as shown at 41 i 6) to form a smooth cylindrical surface adapted to bear freely on the tops of the threads 17 of the actuating sleeve 16, and the rear portion of the actuating member is turned down to form a smooth cylindrical bearing surface 42 for the threaded portion of the pinion 37. The length of the cooper-v ating threads of the actuating sleeve and pinion are so arranged that the threaded portions are in substantially complete engagement when the parts are in operating position as shown in Fig. 3, but the threaded portions are but slightly interengaged when the parts are in idle position as illustrated in Fig. 1, and will be completely disengaged by a predetermined backward motion of the pinion against the pressure of the spring 21 as illustrated in Fi 4 so that the pinion can then spin idly on t e actuating sleeve.

In operation, starting with the parts as illustrated in Fig. 1, rotation of shaft 10 in the direction of the arrow A will cause the pinion 37 to be threaded over into mesh with the engine member 38 until its endwise motion is stopped by the collar 32. Further rotation of shaft 10 will thereupon cause the actuating sleeve 16 to move backward away from the engine member, carrying with it the thrust washer 25 which first compresses the light spring 21 and thereafter bears against and compresses the heavy spring 20 as illustrated in Fig. 3. When spring 20 has built up sufiicient resistance to endwise motion 0 the actuating sleeve, the engine member 38 will be rotated by the pinion 37 and the engine cranked thereby.

When the engine starts, the engine member 38 accelerates and causes the pinion 37 to overrun the actuating sleeve 16 whereby said pinion is threaded back out of mesh with the engine member. This retrograde motion of the pinion may occur with considerable violence and cause the pinion to strike the thrust washer 25 and force it backward against the pressure of spring 21. If the ln'netic energy of the inion is suflicient, the thrust washer 25 will 'e forced back suflicientlg to allow the threads of the pinion to run 0 the threads 17 of the actuating sleeve and allow the pinion to spin idly on said actuating sleeve until brought to rest by the braking effect of the thrust washer 25 a ainst the pinion. -When the pinion has been rought to rest, the spring 21 expands and causes the threaded portion of the pinion to reengage the threads 17 of the actuating sleeve. The points on the ends of the threads 17 are preferably beveledofi as indicated at 43 in order to facilitate this reestablishment of the threaded connection.

In case, during the starting operation, the teeth of the pinion 37 should engage end to end against the teeth of the engine member 38, thus interrupting the motion of the driving member toward meshing position, the actuating sleeve 16 will be moved backward slightly against the resistance of the spring 21 thus providing a time interval which allows the friction in the threaded connection between the actuating member and pinion to build u sufliciently to cause the pinion to be indexe into proper meshing position.

It will be noted that there is here provided an efiicient means for decelerating the demeshing motion of-the starting pinion and preventing its reboundin'ginto engagement 'with the en 'ne member, said function being secured wit out special additional structure, and merely by removing portions of the oooperating elements of the drive, and so permitting a new method of cooperation therebetween.

Although but one form of the invention has been shown and described in detail, it will be understood that this embodiment is not exclusive and that changes may be made in the proportions and arrangements of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. In an engine starter, a member adapted to engage and drive a member of an engine to be started, an actuating member therefor, said driving and actuating members having connections whereby relative rotation causes relative longitudinal motion thereof, means for limiting. longitudinal motion of said members toward said engine member, yielding means for restricting longitudinal motion of said members away from said engine member, said means serving to restrict relative longitudinal movement between said actuating and driving members in either direction, said-connections being adapted to disengage after a predetermined relative longitudinal movement of said members.

2. In an engine starter, a power member, an actuating member mounted thereon for longitudinal movement thereof and rotary movement therewith, yielding means for returning said actuatingmember to'normal position on said power member, said actuating member having a threaded portion and a smooth portion, a driving member threaded on said actuating member for movement into and out of engagement with a member of arr-engine to be started, said driving member when disengaged from said engine member being adapted to run off the threads on the actuat ing member and s in on the smooth portion I thereof, said yiel ing returning means for the actuating member being arranged to limit the dlsengaging movementof the driving backward a predetermined distance from its normal position.

4. Engine starter gearing including an actuating shaft, a pinion threaded thereon for automatic traversal into and out of mesh with a gear of an engine to be started, means for opposing longitudinal movement of the actuating shaft awa from the engme gear, said means bein a apted to yield during the meshing action if a tooth of the pinion abuts a tooth of the engine gear, said pinion being arranged to run off the threads of the actu ating shaft at the end of the demeshing traversal of the pinion, and said yielding means being arranged to oppose such running off of the inion and initiate reestablishment of the t readed connection.

In testimony whereof I have signed this specification.

' YOUSTON SEKELLA.

member, and a brake actuated thereby for restricting the member.

3. In an engine starter, a power member, an actuating member mounted thereon for longitudinal movement thereof and rotary spinning of said driving movement therewith, a driving member having connections with said actuating member whereby relative rotation causes relative longitudinal movement the'rebetween, means for resisting backward movement of the actuating member whereby rotation thereof causes the driving member to be moved into enga ement with a member of. an engine to be started, said means for resisting backward movement of the actuating member being also adapted to yieldingly limit the backward motion of the driving member, said connections being so arranged as to disengage when the driving member is moved

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