US2075916A - Last - Google Patents

Description

G. A. SWEET April 6, 1937;

LAST

Filed June 5, 1936 Patented Apr. 6, 1937 LAST George A. Sweet, Milford, Mass, assignor to United Shoe Machinery Corporation, Paterson, N. J., a corporation of New Jersey Application June 5, 1936, Serial No. 83,706 r 3 Claims.

This invention refers to shoemaking lasts.

Its principal object is to provide a simple, cheap and practical collapsible last having a metallic heel part and a wooden forepart. An all metal last generally of the type herein illustrated is shown and described in the application of George F. Ryan, Serial No. 3,751, filed January 28, 1935.

Some shoe manufacturers, however, desire to retain the advantages of a wooden forepart as well as to obtain those of a metallic heel part. The

wooden forepart is lighter, cheaper, and can be made to accommodate the points of lasting tacks more conveniently than a metallic forepart. In the manufacture of rubber shoes, for which the illustrated last is especially intended, it is of considerable importance to maintain a smooth shoe-shaping surface under the entire shoe upper since any failure in this respect will cause an ineradicable malformation in the ultimately vulcanized rubber material of the upper. Wooden foreparts of collapsible lasts have a very sharp angle at their rear upper edges and after some use become more or less chipped at these edges, thus marring the shoe-forming surface of the 5 19.815.

In order to avoid this difficulty I have, in accordance with the present invention, provided a wooden last forepart having a metallic guard plate on its rear joint-forming surface. The

30 rear surface of the guard plate forms the joint with the heel part and the edges of the plate are shaped to form a continuous shoe-shaping surface with the adjacent surfaces of the heel part and the forepart.

Conveniently, and in accordance with another feature of the invention, the guard plate is bonded to the forepart by the same bonding mechanism as holds the heel part and forepart of the last together, thus providing a cheap and 40 amply strong construction.

These and other features of the invention comprising certain combinations and arrangements of parts will be apparent from the following description of a preferred embodiment of the inven- 5 tion shown in the drawing, in which Fig. 1 is a longitudinal vertical cross-section of the last;

Fig. 2 is a rear elevation of the forepart; and

Fig. 3 is a plan view of the bonding mechanism.

The heel part ll] of the illustrated last is hollow and formed of cast metal; it is open in front, at [2, and has a pin l4 mounted in holes in its side walls. The pin l4 carries a pivoted toggle plate l6 which is operable by means of rack teeth I8 55 by a rack inserted in a hole in the upper surface of the heel part. The plate I6 carries a pivot pin 22 on the ends of which are mounted toggle links 24 each having on its upper side a deep notch 26 to accommodate the pin l4. The front ends of thelinks 24 are pivoted by means of slots 21 on a pin 28 mounted in the end 30 of a lag screw 32 which is set in the forepart 34.

The parts so far described (except the lag screw) are like the corresponding parts of the last illustrated in the Ryan application above referred to, and operate similarly. The rotation of the plate It counterclockwise (Fig. l) throws down the links 24 and breaks the toggle, leaving the heel part It) and forepart 34 sufficiently loose to permit rotation of the heel part upward to collapse the last.

The joint surface between the heel part and forepart is formed as an obtuse dihedral angle. On the heel part the front edges at l2 are plane and, as shown, intersect in a horizontal line at an obtuse angle. The joint surface on the forepart is formed by a similarly shaped plate 36, which fits closely the heel part edges at l2. The plate 36 nests into a similar obtuse-angled depression 38 in the wooden forepart 34. The plate 36 has a forwardly projecting hollow boss 40, which is inserted in a suitable countersunk hole in the forepart 34. The inside bottom surface of the hollow boss 43 forms a seat for a flange 42 between the ends of the screw 32. Thus the insertion of the screw 32 into a previously drilled hole 44 in the wooden forepart 34 will bind the plate 36 firmly to the forepart. The thread of the screw 32 is of a pitch suificiently fine so that the necessity of setting the end 30 vertical will not unduly damage the inside of the hole 44.

The edge surface of the plate 36 forms a smooth surface with the adjacent surfaces of the heel part .and forepart, and the plate is provided with two notches 46, 48 to fit two ribs 50, 52 on the front surface of the heel part to facilitate the proper fitting together of the heel part and forepart when they are drawn together by the toggle I6, 24.

While the forepart and its guard plate 36 are firmly held together, they .can easily be separated in order to provide the last with a new forepart, which may be of the same or of a different style.

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

1. A collapsible shoe last having a heel part and .a forepart, the joint surface between said parts being formed by two planes intersecting in a horizontal line and forming a dihedral angle which is convex forwardly, a guard plate mounted on the forepart and shaped to fit the said dihedral angle on both the forepart and 5 the heel part, a bonding screw mounted in the forepart and having a head clamping said guard plate firmly to said forepart, and a releasable tension mechanism connecting the head of said screw to said heel part, to permit collapse of 10 the last.

2. A collapsible shoe last having a heel part and a forepart, a screw in the forepart, a pin in the heel part, a toggle mechanism joining the pin and the head of the screw to hold the 15 heel part and forepart together in operative position, and a guard plate interposed between the heel part and the forepart and having a seat projecting into the for'epart, said screw having a flange seated upon said seat to clamp.

20 the guard plate to the forepart.

bind said plate firmly to said forepart, and a releasable tension mechanism connecting said screw to said heel part, the edges of said plate and the adjacent surfaces of said heel part and forepart forming a continuous shoe-shaping surface.

GEORGE A. SWEET.

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