US936138A - Hinged last. - Google Patents

Description

Patented Oct. 5, 1909.

, 30. itself, and by providing a forepart and heelfr onmcn.

.EDWIN O. KRENTLER, OF DETEG-IT, MICHIGAN, AiSSIGNOR TO KRENTLER-ARNOLD HINGE LAST COMPANY, OF DETROIT, MICHIGAN, A CORPORATIGN 0F MICHIGAN..

HINGED LAST.

936,138. Specification of Letters Patent. atented @en 5, 1909.

Application led May 3, 1909. Serial No. 493,503.

To all whom it 'may concern:

Be it known that l, EDWIN O. KPENTLER, a citizen of the Unite-d States, and resident v of Detroit, in the county of Wayne and '.3 State of Michigan, have invented an lmprovement in Hinged Lasts, of which the following description, in connection with the accompanying drawings, is a specification, like numerals on the drawings representing like' parts.

To keep pace with the modern machinery and processes used in-shoe manufacture, it Y becomes constantly necessary to provide still y stronger hinged lasts, as the early forms of hinged lasts, although sufficiently strong and practical for shoe manufacture as then conducted, fail'to stand up to the present requirementsl Accordingly my presentinvention aims to provide a hinged last capable of enduring the utmost degree of vertical and twisting strains, blows, and rough usage to which a last is subjected, at the present time. Ithave secured this desired object by -providing an interlocking construction of such-shape' at the hinge joint that the vertical and twisting strains (as for instance those brought on the last during the leveling process) are sustained almost entirely by the contacting surfaces or walls of the wood part as nearly as possible with uncut, intact or integral abutting ends. y

As `heretofore constructed, ithas been considered necessary in hinged lasts to provide saw cuts and kerfs in the'abutting ends Aof the last-parts at the hinge joint for receiving .the hinging means, locking means, etc., and I have found that most of the weaknessesl and breakages and defects of lthe 40 hinged last in use have been due to this cuttingawvay of the wood and the consequent introduction'of lines and planes of weakness which promote the' splitting and breaking down of the lasts.l I, eliminate all thesesimply by providing a relatively small and high knuckle joint of considerable overlapping eXtent, and connect v the last-parts by a .central cylindrical dowel-like hinge which necessitates merely theyboring of a short longitudinal hole intojthe end ofthe forepart and intothe end of the heel-part the hole in the latter being`enlargedslightlyV ,to permit the required pivotalv movement of; the-heel-part. 4 By this means. the? co'ncavlorl'f joint take up all twisting strains and give mutual support against vertical, longitudinal and all other strains, while the single dowellikehinge in the said two bored holes inentioned is surrounded on all sides by the virgin wood, which, being irrtact or uncut, affords the greatest strength possible against splitting and the like. As neither last-part contains any angular recess, kerf,or cnt` transversely through or across its secant end, there is present no tendency to split or to start a cleavage in any particular direction. Furthermore, as my last depends for its main strength upon the intact wood and the hrm interlocking relation of the curved surfaces of the wood at the knuckle joint. l provide special locking means for maintaining the contacting surfaces of the wood always in unyielding, mutual-supporting engagement when the last is in lengthencd Iposition.

The further constructional details of my invention and advantages thereof will be pointed out more at length in the course of the following description, considered with reference to the accompanying drawings, in which I have shown a preferred embodiment of the invention.

In the drawings, Figure l represents in side elevation, partly broken away, a last constructed according to my invention: Fig. ,2 is a view thereof inside elevation showing the last collapsed: Fig. 3 is a cross-sectional View thereof at the joint taken on.the line 3 3, Fig. l, looking toward the forepart: and Fig. 4t is a cross-sectional view looking toward the heel-part taken on the line l, Fig. l. n

For convenience of i illustration, `l have shown a conventional form of last, comprising a forepart l and a heel-part '2. Instead of severing these parts from each other along the usual lines which have betr; d long followed in hinged lasts, l provide. a knuckle 3 of short radiusin the heel-'part having 'its surface a curved c'oncentrically from the pivotcenten 5 and carried at'its 55, convex surfaces ofthev short-,radievis"knuckle rpart, overlapping practically the entire knuckle of the heel-part and preferably extending rearwardly to the pivot thereof, By

- this means notfonly is the convex surface of the knuckle 4held firmly and solidly in the concave complemental .seat 9 forniedY therefor in the forepart, but the projecting end 8, extending as it does throughout the entire width of the last and rearwardly sufliciently to provide a broad horizontal bearing or support, 'insures a bracing strength y or strut-like eect which adds very materially'to the total strength of the last-joint.

The end of the projection 8 abuts squarely againstthe adjacent end. or wall of the heelpart, and gives an exceedingly strong bracing effect to that which has already been mentioned. Also this constructionresists all tendency of the last to buckle or collapse bottomward. At its top side vthe last-parts are severed along the lines-10, ll'respectively so` as to provide a lgap or opening 12 to permit one part to turn on thev other about the pivot 5. A single hole is bored at 13 into the forepart and at 14 into the heelpart corresponding 4in size to the hinge ortubular plug 15 (laterally enlarged verticallyl in theheel part topermit the pivotal action) which is then driven thereinto and4 secured by pins or rivets 5, 16, the former constituting the pivot or hinge pintle of the last about which the heel-part turns in moving from shortened to Alengthened position or vice versa. In a last of this description, in l which the' wood is depended upon for givingthe main strength, etc., more or less shrinkage will inevitably take place, and accordingly I screw ,into the heel-part a small threaded stud 17 whose forward end terminates" close to the forepart when the last 'is in extended or lengthened position, and *piv ".oted at 18 on the adjacent wall of the fore- 'strength part a wear-plate orlatch 19 which is normally held under tendency to. move across the front end of the pin 17 by a spring 20. Thus when the last is turned into its fully lengthened position,l the plate 19 snaps tightly in front of the pin 17 for the latter lto bear against. As the lastshrinks or the plate wears, the pin 17 is turned correspond-- ingly outward so asto maintain at all times -a perfectly snug tight fit. The plate 19 is provided with an rear or finger-hold 21 to 2permit it to be conveniently moved back# lward by the operator, andthe heel-part is preferably cut away at 22therefor.

I am aware thatlasts `have been heretofore constructed or proposed with a knuckle joint (as shown lfor instance in my Patent No. 864,654 or the Pym patent No. 608,006), but

never as herein shown nor withthe advantages herein set forth, but I do not claimthe` 'same broadly herein, but only when s o con-y structed as to secure the' advantages of andoperation already .fexplalned j rangement of union or hinging member is also new and herein claimed in its coperative relation to the adjacent parts and construction" AlsoI wish it understood that Ycations in constructional details and combideparting from Ithe spirit and scope of the invention aslhereinafter claimed.

l Having described my invention, what I claim as new and desireto secure by Letters Patentis:. t l

. 1. A hinged last, comprising fore-part in the socket-containing part to hold said plug immovably in the last, and a pivot pin extending through the opposite end of said plug and into the adjacent last-partconcenknuckle having vertical enlargement, suiicient only to permit the requisite pivotal movement of the heel part, the wood of -said last-parts around said holes being otherwise uncut andintact. y

'2. A hinged last, having a heel part provided with a knuckle of relatively short radius projecting from .its front end and extending horizontally across the last, a forepart provided with a complemental concave socket in contact with which'said knuckle'is lower end projecting rearwardly to overlap the knuckle and abut against the `heel part for resisting vertical and longitudinal vpreslsures, said fore-part and heel part having central longitudinal hinge-holes formed in their abutting socket and knuckle ends, the -wood of said last-parts'around said holes being circumferentially intact about the'hingeholes. at .the secant ends of the last-parts, a

pin extending through' the fore-part and for- -'ward end of said plug for retaining'the lat-A ter immovably in the'forepart, and a transverse pivot pin .extending through said knuckle and-the rear end lof'said plug on which the heel part swings with relation to the forepart.' f -I 3. A hingedlast having a heel-part pror'einafter claimed. The 'special ardiu's projecting from its front end and -exatending horizontally across the last land my invention is capable of various modifi.

-nation and arrangement ofl partsv withoutv trically of said knuckle, said hole in thel arranged to turn, said forelpart having its rigidv plug held inl said holes, a transverse I videdwith a knuckle of relatively short ra--F and a heel part, one part being provided; 83

means cooperating with the .walls of the hole seance teriniiiating on its under side Within the *i turn, said torepart having its lower end projecting,rearivardlyto overlap the entire kinickle and abut against said wall from said knuckle to the bottoni' of thelast for resisting vertical. and longitudinal pressures, antlvf'igigid hinging means embedded Within #aid knuckle and pivoted concentrically therein and inunovably securedin the .torep'art.

Il. Ei hii'iged last lia-ving a heel-part provided ivit h a knuckle of relatively short. ra dius projecting troni its front end and extending horizontally across 'the last and terminating ou its underside Within the body of the last above the bottoni, and having a 'wall extending` thence dovvntvardl;v to the bottoni orn the last in position to resist longitudinal strains, a orepart provided 'with a conipleinental concave socket in contact with which said knuckle is arranged to turn, said orepart having its lower end projectingv rearvvardl to overlap the entire knuckle and abut against said Wall from said knuckle to the bottoni of the last for resisting vertical and longitudinal pressures'7 said forepart and heel-part having central longitudinal hingeholes i'roruied in their abutting socket and knuckle ends, the Wood of said last-parts around said holes being circuniferentially intact about the hinge-holes at the secant ends ofthe last-parts,` a, rigid plug held in said holes, a transverse pin extending ihrough'the forepart. and forward end of said plug for retaining the latter innnovable in the torepart, and a transverse pivot pin extending through said knuckle and the rea-r 'end of said plug on which the heel-part swings o.

`with relation to the forepart. hinged last, having a heel part provided 'with a knuckle of relatively short radius projecting from its front end and eX- tending horizontally across the last, a forepart provided with a coinplcniental concave socket in contact with which said knuckle is arranged to turn, said iorepart having its vlovver end projecting rearwardly to overlap the knuckle and abut against the heel part for resisting vertical 'and longitudinal presseres7 said forepart, and heel part having central longitudinal,hingsholes formed intheir abutting socket and knuckle ends, shape-d to receive a. plug connection and peruit 'the necessary last. inoveinents, and the surrounding wood thereof being othertvlse uncut and in original 'intact osrtion, and a plug-like connection fitted an( secured at its opposite ends in said hlngehoies in the iorenart and heel para; r aspectively to per-rait the knuckle to turn in the socket While nreventing vthe separation of the last-:garten (S. A 'hinged last, comprising, a t'orepart and heel-part, one of which is provided with a projecting knuckle extending transversely across the last and terminating on; under side at an interior point-in the .bodyj f last above the bottonn" afifid the 5@the which is provided with a' conipleinental cave socket in which said to turn, the last-part (Ing: having its adjacent .bottom7l d overlap 'the socket to the'eittrcne o ver2-end thereof at said interior 1point i; thA hi'dy idf the last above the bottoni, vsaid- ,tyfe lastvparts liront said interior pointto thefbottom 'of the last 'having uprightabutting Walls for resisting longitudinal and vertical pres surcs brought upon the last, said two lastparts at approximately the transverse and vertical middle of their knuckle and socket respectively having a longitudinal hole,

shaped to receive a plug connection and per mit the necessary last movements7 and the surrounding Wood thereof being otherwise uncut and in its original intact position, and

a plug-like connection fitted and secured at its opposite ends in said hole in the torepart and heel-part respectively to permit the knuckle to turn in the socket While preventing'the separat-ion of the last-parts.

' 7. A hinged last, comprising a orepart and heel-part, one of which is provided` With a projecting knuckle extending transversely across the last and terminating on its under side at an interior point in the body of the .last above the bottoni, and the other of which is provided Iwith a coinpleinental concave socket in which said knuckle is seated to turn, the last-part vcontaining' said sockethaving its adjacent bottoni end arranged to overlap the socket. to the extreme loWer'endV thereof at said interior point in the body of the last above the bottoni, said two last-parts from said interior point to the bott-oni of the last lia-ving upright abutting walls for resisting' longitudinal and vertical. pressures brought upon the last, said two last-parts at approximately the transverse and vertical middle of their knuckle and socket respectively having a longitudinal hole the hole in the knuckle having vertical elongation to permit of the pivotal action of the heel part.,

andl the surrounding Wood thereof beingV otherwise uncut andin its original int-act positiona plugdike connection fitted and secured .n its opposite ends in said hole in the orepart and heel-part respectively to perinit the knuckle to turn in the socket While terininatiifig close to the tace of the opposite e denounced last-part, and a Wear-plate movable into and out of position across the end of said pin.,

8. In a, hinged last, a forepart and heelw part pivotally connected and separated so as f the opposite last-part.

to provide cent upper ends,

an opening between their adja7 combined with a pin ad- .j ustably mounted to project across said opento provide an. opening between their adja- 1 15 cent upper ends, combined with a pin threaded into'the face of one last-spartto project across said opening close tothe adjacent face of the opposite last-part, ai Wear-plate pivotally mounted on the face of the latter last-partto swing across the end of said pin when the last-parts are in fully lengthened position, and a spring for normally holding said plate under normal tendency to move into the last-mentioned position.

vIn testimony whereof, I have signed my name to this specification, in the presence of two' subscribing Witnesses.

EDWIN o.` KRENTLER.

Witnesses lV. A. FRASER, '0. E. FREEMAN.

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