US3040349A

US3040349A - Foreshortening lasts

Info

Publication number: US3040349A
Application number: US66783A
Authority: US
Inventors: Jr Victor J Levaggi
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1960-11-02
Filing date: 1960-11-02
Publication date: 1962-06-26
Anticipated expiration: 1979-06-26

Description

June 26, 1962 v. J. LEVAGGI, JR 3,

FORESHORTENING LASTS Filed Nov. 2, 1960 2 Sheets-Sheet 1 Inventor Victor fLevaygz' Jr z By his Attorney United States 3,040,349 FORESHGRTENING LASTS Victor J. Levaggi, Jr., Beverly, Mass, assignor to United Shoe Machinery Corporation, Boston, Mass, a corporation of New Jersey Filed Nov. 2, 1960, Ser. No. 66,783 4 Claims. (Cl. 12136) This invention relates generally to lasts of the type which comprise a forepart and a heel part hinged together, and has particular reference to a last of this type which is adapted to be opened and closed by automatic machinery.

Withincreasing automation of shoe manufacture, it has been found desirable to provide means for automatically opening the last in a completed shoe in preparation for removal of the shoe from the last, and for automatically closing the last, after the shoe is removed therefrom, prior to returning the last to storage.

Accordingly the object of the invention is to provide an improved last which is particularly adapted for operation by automatic machinery.

A further object of the invention is to provide a two part last comprising a connecting and locking link which is adapted to unlock and open the last by movement in one direction, and close and lock the last by'movement in the reverse direction.

A further object of the invention is to provide a last assembly in which the forepart and heel part are retained in assembly by a connecting link which is formed of a single piece of sheet metal which is longitudinally resilient to draw the last parts tightly together when they are in the closed position.

Other objects of the invention will be apparent to one skilled in the art from the following description of a specific embodiment thereof.

In the drawings:

.FIG. 1 is a view in side elevation, partly in section, of a last embodying the features of the invention disposed in a completed shoe with the last link moving to the unlocked condition in preparation for opening the last to remove the shoe from the last;

FIG. 2 is a view similar to FIG. 1 with the last in the open position;

FIG. 3 is a view of the last of FIG. 1 after the shoe has been removed and the last closed and locked; and

FIG. 4 is a view in section taken on line IVIV of FIG. 3.

Referring to the drawings, there is illustrated a last which comprises a heel part 12 and a forepart 14 joined by a connecting link 16. The heel part 12 is provided with a thimble hole 18., opening to the upper surface, to receive a thimble post 20 disposed in a support jack 22.

The last 10 is of the type which is adapted to foreshorten by downward tilting of the forepart in relation to the heel part (as observed when the last is in the upright position, i.e. bottom down), and for this purpose the heel part and forepart have arcuate mating surfaces 2 and 26, with a projection 28 in one part adapted to enter a correspondingly shaped recess in the other part to prevent relative movement of the parts when they are drawn tightly together in the closed and locked condition.

To receive and permit operation of the link 16, the heel part and forepart are provided with relatively

narrow slots

30 and 32 respectively. The slot 3d in the heel part opens to the top of the last to permit operation of the link in a manner to appear hereinafter.

The link 16 extends from the slot in the heel part into the slot in the forepart, and to retain the link and the last parts in assembly, the portion of the link in the heel part is provided with a pivot aperture 34, receiving an anchor 3,04%,349 Patented June 26, 1962 pin 36 extendingtransversely in the slot 30, and the portion of the link extending into the forepart is provided with a locking aperture 38 receiving a locking pin 40 extending transversely through the slot 32. To provide a resilient locking action as will appear hereinafter, the medial portion 42 of the link is offset laterally from a line extending between the apertures 34 and 38 to impart longitudinal'resilience to the link.

The locking aperture 38 is elongated in a direction generally transverseto a line joining the apertures and as viewed in the drawing has an upper locking portion 44 and a lower unlocking portion 46 separated by a rearwardly projecting curved portion 48. The forward edge of the locking portion 44 of the aperture 38 is so positioned in relation to the position of the locking pin 40 that when the last is closed and the link is in the lower position, so that the pin 40 is seated in the locking portion, the link is maintained under tension between the pins, to draw the last parts tightly together. (See FIG. 3.) The forward edge of the unlocking portion 46 of the aperture is so spaced in relation to the locking pin that when the link is pivoted upwardly (see FIG. 1) the forepart 14 of the last may be moved away from the heel part far enough to disengage the projection 28 from its notch and permit the forepart to move upwardly to open the last and effect foreshortening to permit removal of a shoe disposed thereon. (See FIG. 2.)

To enable the last to be opened and closed by automatic machinery the link 16 is provided with an operating arm 50 which extends out of the top of the last from the .rear end of the link so that forward and rearward motion of the arm 50 about the pivot pin 36 effects unlocking and locking of the last as will appear hereinafter. To enable the operation to be accomplished by an operating lever 52 of an automatic machine (not shown) the arm 50 may be provided with a lever engaging means such as a notch '54.

In normal use, the last is maintained in storage in the closed condition, and is also maintained in the closed condition throughout the manufacture of a shoe thereon. When the shoe is substantially completed, the last and shoe may be placed in any convenient handling mechanism (not shown) of which the jack 22 may be a part, with means for bringing the operating arm 50 of the link into operative relation with the lever 52.

As illustrated in FIGS. 1 and 2, forward movement of the link arm 50 first effects unlocking of the forward end of the link from the locking pin 4'0 by causing counterclockwise pivoting of the link about the pivot pin 36 so that the portion 48 rides over the pin and the unlocking portion 46 of the aperture 38 moves into position around the pin 40. The presence of the shoe in the last tends to prevent separating of the last parts, however, the rear edge of the portion 46 of the aperture, which is inclined generally forwardly, tends to force the pin 44 and the fore part of the last forwardly far enough to disengage the projection 28 from its recess. Thereafter, further forward motion of the arm 50, in pivoting the link further counterclockwise opens the last by tilting the fore Part thereof upwardly as viewed in FIG. 2 to effect foreshortening thereby permitting removal of the shoe, either manually or by automatic mechanism (not shown).

After the shoe has been removed from the last, reverse movement of the lever 52, causing forward movement of the link arm 50, will initially cause the forepart of the last to be returned to the closed condition so that the

surfaces

24 and 26 are again in engagement, and then cause the last parts to be drawn tightly together as the portion 43 rides over the pin 40 to permit the pin 40 to seat in the locking portion 44, with the link being thereby maintained under longitudinal tension as previously described. Thereafter the last may be removed from the jack 22,

either by hand or by suitable mechanism and returned to storage.

The above described last structure has a number or advantages over lasts of the prior art resulting from the use of a single relatively thin piece of resilient material as the connectinglink, and the method of incorporating said link into the last structure. One of the principal disadvantages of many types of foreshortening lasts is the lack of strength resulting from removal of material to accommodate the locking mechanism. When large cavities are required in the heel part and forepart to receive a locking mechanism; the ability of the last to resist the forces involved in shoeemaking operations such as sole leveling and heeling is greatly reduced. However, in-the last disclosed herein only a narrow slot is required in the forepart and heel part to accommodate the link. Hence the strength of the last is not appreciably impaired.

Another advantage of the disclosed structure is the fact that, in the design of a particular last tariff, the desired strength of the locking mechanism may be readily attained by a proper selection of the thickness of the link without changing other dimensions thereof. Hence a single punch and die set may be utilized to form links having different locking strengths.

Although in the illustrated embodiment, the longitudinal resiliency of the link is imparted by the offset medial portion it will be understood that other shapes imparting longitudinal resilience may be utilized.

Since certain other modifications may be made in the device without departing from the scope of the invention it is intended that all matter contained herein be inter preted in an illustrative and not in a limited sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A two-part foreshortening last comprising a forepart and a heel part having abutting faces, said last being adapted to open and become foreshortened by downward tilting of the forepart in relation to the heel part, said parts each having a recess extending into the part from the abutting face and a transverse anchor pin disposed in each recess, and a connecting link extending between the anchor pins, said link being pivoted to the anchor pin in the heel part and having means engaging the anchor pin in the forepart, saidrineans having a locking position engaging the anchor pin in the forepart so as to draw the last parts tightly together and an unlocking position in which the forepart may tilt downwardly in relation to the heel part to open the last, said link being movable from the locking position to the unlocking position by downward pivoting, whereby downward pivoting of the link after unlocking causes the last to open.

2. A two-part foreshortening last as set forth in claim 1 in which said link is longitudinally resilient between said anchor pins and the means engaging the anchor pin in the forepart is so positioned that said link is maintained in longitudinal tension when in the locking position to draw said last parts tightly ogether.

3. A two-part foreshortening last as set forth in claim 2 in which said link is longitudinally resilient and is maintained in a flexed condition to draw the last parts tightly together when the link is in the locking position.

4. A two-part foreshortening last comprising a forepart and a heel part having abutting faces which have interengaging portions to prevent relative movement when the parts are drawn tightly together, each of said parts having a narrow vertical recess extending in from the abutting face, a transverse anchor pin in each recess spaced from the abutting face, and a connecting link disposed in said recesses and extending between said anchor pins thereby maintaining the last parts in assembly, said link being pivotally joined to the anchor pin in the heel part and having an aperture in the portion disposed in the forepart receiving the anchor pin disposed therein, said link having a portion between the pins which is longitudinally resilient, said aperture being elongated in a direction generally perpendicular to a line between the pins and being shaped and positioned to provide a locking portion at the lower end thereby, and an unlocking portion at the upper end separated by a shoulder portion.

References Cited in the file of this patent UNITED STATES PATENTS 2,429,233 Lev-aggi Oct. 21, 1947