US2849094A - Jaw clutch meshing device - Google Patents

Description

Aug. 1958 J. c. VAlDEN 2,849,094

JAW CLUTCH MESHING DEVICE Filed June 28, 1955 INVENTOR. JOHN C'. VAIDE N JAW CLUTCH MESHIN G DEVICE John C. Yaiden, Packanack Lake, N. J., assignor to Bend1x Aviation Corporation, Teterboro, N. J., a corporation of Delaware Application June 28, 1955, Serial No. 518,441 6 Claims. (Cl. 192-67) This invention relates to engine starter meshing mechamsm. It is particularly concerned with a novel jaw clutch meshing device.

The general object of the invention is to prevent customary clashing of the jaws of a starter with those of an engine during engaging operations, as well as to prevent ratcheting of the jaws during disconnect operations.

This general object is accomplished by blocking means, associated with the starter and interposed between the jaws of the starter and of an opposed engine. The arrangement of the blocking means is such as to allow engagement of the opposed jaws without clashing during starting operations, and to block the jaws from ratchetmg with one another while the jaws are disconnected. The actions of the blocking means are controlled by the rotation of the starter relative to that of the engine.

The invention further lies in the particular construction of the device, and in the general organization of its various parts, as well as in their cooperative association with one another to produce the results intended. thlThe foregoing and other objects and advantages of s a consideration of the detailed description which follows, taken together with the accompanying drawings wherein an embodiment of the invention is illustrated. It is to be expressly understood, however, that the drawings are for purposes of illustration and description and are not to be construed as defining the limits of the invention.

In the drawings:

Fig. 1 is a longitudinal section through starter-engine meshing mechanism, embodying the invention and showing the several elements engaged to one another;

Fig. 2 is a left end View of the starter jaw together With the associated blocking member superimposed thereon;

Fig. 3 is a left end View of the starter jaw with the blocking member removed;

Fig. 4 is a right end view of the blocking member; and

Fig. 5 is a view similar to Fig. 1 but showing the blocking member and engine jaw disengaged from one another.

Reference is now directed to the several drawings wherein there is disclosed a starter jaw member 1 having a jaw head 2 at the end of a stub shaft 3. The latter slidably engages by internal straight splines a complementary splined end 4 of a driving screw member 5. The jaw member is prevented from sliding free of the screw member by a bolt 6. Bolt 6 is axially secured, as by threads and nut 7, at one end in a center wall 8 of the starter jaw member. The shank of the bolt passes freely into the hollow interior of the screw member and through a ring stop 9 internally of the latter. A compression coil spring 10 about the bolt acts upon the jaw member, forcing it leftward on the splined end of the screw member until a headed end 11 of the bolt limits against the stop 9. The screw member 5 is helically operable by conventional starter drive mechanism,

invention will appear more fully hereinafter from.

2,849,094 Patented Aug. 26, 1958 not shown, whereby it is caused to be advanced axially outward and rotated, carrying the starter jaw member 1 With it to engage and drive an associated engine jaw 12.

The starter jaw head 2 has formed in its end face at the marginal edge thereof a ring of teeth 14 (Fig. 3) which are engageable with a complementary ring of teeth 15 (Fig. 5) formed in an end wall 16 about the marginal edge of the engine jaw; whereby, upon engagement of the jaw members (Fig. 1) and rotation of the starter jaw, the associated engine is cranked.

When the engine starts and picks up speed, exceeding that of the starter jaw member, the latter is thrust out of engagement by the faster rotating engine jaw. Until the starter jaw driving mechanism, not shown, comes to rest, there is a tendency of the starter jaw to return toward the rotating engine jaw. Here, an interposed blocking ring member 17 blocks re-engagement of the opposed jaws, and thereby avoids ratcheting of the jaws which would otherwise occur.

The right end 18 of this blocking ring member is receivable in a shallow recess 19 formed in the left end of the starter jaw. The teeth 14 of the starter jaw border this recess. About the peripheral surface of the blocking ring is a ring of saw teeth 20 of slight radial thickness, which are engageable with the inner radial portion of the starter jaw teeth 14. When the teeth of the blocking ring are fully engaged with those of the starter jaw, the right end face of the blocking ring is in the shallow recess 19 and in close proximity to the recessed wall 21 of the latter. The radial expanse of the starter jaw teeth is relatively greater than that of the blocking ring teeth as well as that of the engine jaw teeth. It is able to accommodate the teeth of both of the latter elements. The outer marginal portion 22 (Fig. 2) of the starter jaw teeth, which is not engaged by the teeth of the blocking ring, is engageable with the opposed complementary teeth of the engine jaw (Fig. 1).

When the blocking ring and starter jaw are engaged, as in Fig. 1, the left face of the thickened blocking ring projects axially a short distance beyond the engaged teeth to the left, as at 23 in Fig. 1. To enable the teeth of the engine jaw to be engaged by the outer marginal portion 22 of the starter jaw teeth, the right end of the engine jaw is skirted, and the teeth of the engine jaw are formed in the end wall 16 of this skirted portion. This skirted end provides a shallow recess 24 which is only deep enough to accommodate the left end 23 of the blocking ring to the extent required to enable the teeth of the starter jaw to fully bottom in the teeth of the blocking ring and in those of the engine jaw.

It is to be noted, that engagement of the teeth of the engine jaw with the related portion of the starter jaw is only possible when the blocking ring is fully bottomed in the recess 24 and when the teeth of the blocking ring are engaged with their complementary portion of the starter jaw teeth. When the blocking ring member is not so engaged, the ends of its teeth are caused to rest upon blunted ends of the starter jaw teeth (Fig. 5). When the blocking ring is in the latter position, the starter jaw is blocked from engaging the marginal portion of its teeth with those of the engine jaw. This is due to the shallowness of the recess 24 in the opposed engine jaw in which the blocking ring bottoms.

The blocking ring member is normally held in its disengaged position (Fig. 5) and has this position when the starter jaw mechanism is at rest or is disengaged from the engine jaw. To obtain and hold this normally disengaged position of the blocking ring, a ribbon type torsion spring 25 is provided. One end of the latter is anchored at 26 to the recessed wall 21 in the starter jaw; and the other end 27 is retained (Figs. 2, 4-) in a radial slot 28 formed in the inner wall of the blocking ring. A circumferentially disposed pocket 29 in the right end face of the blocking ring is provided to overlie the anchored end 26 of the spring, so as to avoid interference of the anchoring means with operating actions of the blocking ring. A second similarly disposed pocket 31 in the right end face of the blocking ring is intended to overlie .a heavy stud 32 projecting axially from the recessed wall of the starter jaw.

The relation of the blocking ring member to. the starter jaw is such that, when the torsion spring is wound slightly, the starter jaw and blocking ring are drawn angularly into engagement with one another. When the spring is relaxed, these members are cammed out of engagement bythe related teeth. The spring is limited in the extent to which it may relax by a shoulder 33 of the pocket 31 limiting against the stud 32 (Fig. whereby the disengaged teeth of the blocking ring are caused to come to rest upon blunted ends of the teeth of. the opposed starter jaw, as in Fig. 5.

In the operation of the described mechanism to effect engagement of the opposed jaw members, actuation of the helical drive screw 5, in conventional manner, causes the starter jaw member to axially advance toward the opposed engine jaw. Whereupon, the projecting end 23, which has afriction face, of the blocking ring enters the engine jaw recess .and frictionally grips the recessed. wall 24 of the latter. As a result of the latter action,. the torsion spring is caused to be wound by rotation of the starter jaw. Thiswinding action of the spring permits the starter to move axiallly into meshing engagement with the blocking ring; and, as the latter occurs, the outer portion 22 of the starter jaw teeth engage the teeth of the engine jaw. The engaged members then rotate as a unit, and the engine starts up.

Now, after the engine starts and accelerates to a speed greater than that of the starter jaw, the latter is, thrust out of engagement from the engine jaw. In this latter action the torsion spring relaxes and slides the starter jaw out of engagement from the blocking ring. Whereupon, the blocking ring is carried to its normal disengaged position upon the blunt ends of'the starter jaw teeth, as in Fig. 5. Until the starter jaw has come to rest,v it tends to return toward the high speed rotating. engine jaw. If allowed to do so, clashing of the opposed teeth and possible damage would occur. The blocking ring, however, in its disengaged position, blocks against such clashing of teeth.

While an embodiment of the invention has been illustrated and described indetail, it is tobe expressly understood that the invention is not limited thereto. Various changes can be made in the design and arrangement of the parts without departing from the spirit and scope of the invention, as the same will now be understood by those skilled in the art; and it is my intent to claim the invention not only as shown and described, but. also in all such forms and modifications thereof as may be reasonably construed to be within the spirit of the. invention and the scope of the appended claims.

What is claimed is:

1. In engine starter jaw clutch meshing. mechanism of the character described, a starter driving jaw having. a.

ringof radially bro-ad saw teeth in an end face, an op.- posed. thickened ring having peripheral saw teeth engageable with the inner radial portion of the starter jaw teeth;

and torsion spring means. anchoring the thickenedring to the starter jaw adapted, when wound in a particular direction, to permit the opposed members to move into toothed engagement with one another, and when relaxed, to assist to axially slide the ring out of toothed engagement from the opposed starter jaw.

2. 111 engine starter mechanism of the character described, a starter driving jaw having a ring of radially broadsaw teeth in an end face thereof; an opposed thickened ring having peripheral saw teeth engageable with the inner radial portion of the starter jaw teeth; ribbon type torsion spring means anchoring the thickened ring in opposed relation to the starter jaw and adapted, when wound in a particular direction, to permit the opposed members to move into toothed engagement with one another, and when relaxed, to assist to axially slide the thickened ring out of toothed engagement from the starter jaw; and means for limiting the relaxed position of the torsion spring at a point where the ends of the teeth of the thickened ring abut the ends of the teeth of the starter 3. In engine starter mechanism of the character described, a starter driving jaw having a ring of radially broad saw teeth in an end fact thereof; an opposed thickened ring having peripheral saw teeth of small radial thickness engageable with the inner radial portion ofthe starter jaw teeth; a torsion spring anchoring the thickened ring in opposed relation to the starter jaw and adapted, when wound in a particular direction, to permit the op.- posed members to move into toothed engagement with one another, and when relaxed, to assist to axially slide the thickenedring out of such engagement; a stud in a recess of the starter jaw; and a shoulder formed ina face of the opposed thickened ring cooperable with the. stud, upon relaxing of the torsion spring, to limit the relaxed position of the torsion spring at a point where the ends of the teeth of the thickened ring abut. the ends of the teeth of the starter jaw.

-4. In engine starter mechanism of the character described, a starter driving jaw having in an end face a ring of radially broad blunt ended saw teeth, an opposed thickened ring having peripheral saw teeth of small radial thickness engageable with the inner radial portion of the.

starter jaw teeth; a torsion spring anchoring the thickenedring in opposed relation to the starter jaw and adapted, when wound in a particular direction, to permit the opposed members to move into toothed engagement with one another, and when relaxed, to axially slide the. thick ened ring out of such engagement; a stud in a, recess of the starter jaw engageable with a shoulder in the end face of the opposed thickened ring to limit the position ofthe latter, upon relaxing of the torsion spring, to a point where the teeth of the thickened ring abut the. bluntends of the teeth of the starter jaw.

5. In engine starter mechanism of the character, described: an axially movable and rotatable starter driving jaw having a ring of radially broad saw teeth in an end face thereof; an opposed engine jaw having in an end face thereof a ring of radially extending but relatively narrower saw teeth engageable with the outer radial portion of the engine jaw teeth; a thickened ring partly receivable axially in a recess of the engine jaw and having an end face adapted to frictionally engage an opposed wall of the recess; the ring having peripheral saw teeth around it of small radial thickness and engageable in the opposed inner radial portion of the starter jaw teeth; torsion spring means anchoring the thickened ring to the starter jaw; the torsion spring means having a normal position wherein the teeth of the thickened ring are axially held out of engagement from the teeth of the starter jaw and the ends thereof abut the ends of the teeth of the latter, and having a wound position wherein the teeth of the starter jaw are axially drawn into engagement with those of the thickened ring and the teeth of the engine jaw; the thickened ring in normal position serving to space the starter jaw out of engagement from the engine jaw; and means for driving the starter jaw axially to move the end face of the ring into. frictional engagement with the recessed wall of the engine jaw and for rotating the starter jaw, whereby the torsion spring is wound to draw the starter jaw into engagement with the teeth of the thickened ring and those of the engine 6. In engine starter mechanism of the character de scribed: an axially movable and rotatable starter driving jaw having a ring of radially broad saw teeth in an end face thereof; an opposed engine jaw having in an end face thereof a ring of radially extending but relatively narrower saw teeth engageable with the outer radial portion of the engine jaw teeth; a thickened ring partly receivable axially in a recess of the engine jaw and having an end face adapted to frictionally engage an opposed wall of the recess; the ring having peripheral saw teeth around it of small radial thickness and engageable in the opposed inner radial portion of the starter jaw teeth; torsion spring means anchoring the thickened ring to the starter jaw; said torsion spring means normally positioning the teeth of the thickened ring axially out of engagement with the teeth of the starter jaw and the ends thereof in abutment to the ends of the teeth of the latter;

References Cited in the file of this patent UNITED STATES PATENTS 2,574,004 Zingsheirn Nov. 6, 1951 2,667,252 Meyer Jan. 26, 1954 FOREIGN PATENTS 418,328 Great Britain Oct. 23, 1934 1,099,090 France Mar. 16, 1955

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