US2231855A - Cutting die - Google Patents

Description

Feb. 11, 1941 c. I. STODDARD ETAL CUTTING DIE Filed March 2, 1940 Patented Feb. 11, 1941 CUTTING DIE Charles I. Stoddard, Quincy, and Ernest 0. Larson, Wollaston, Mass.

Application March 2, 1940, Serial No. 321,888

1 Claim.

This invention relates to certain improvements in cutting dies primarily intended for use in connection with clicldng machines used for dieing out upper leather for parts of shoes.

So far as we are aware, dies for this purpose have almost universally been made entirely of metal, the chief objection to which is the cost of manufacture. Various attempts to reduce the cost of manufacture have been made, the results of which have not been entirely satisfactory, so that the all metal dies are still extensively used. One of these attempts consisted in applying a metal binding strip to a core of fiberboard which has been cut out in the form of the desired pattern and attaching a cutting blade to the metal binding of the pattern by spot welding. This arrangement necessitated the use of a narrow blade, or a blade of substantially less width than the blades of the all-metal dies, and operators objected to the use of these narrow blades on account of the fear of getting their fingers crushed in the clicking machine.

The objects of our invention are to provide a. die which will have all the advantages of inexpensive construction and lightness possessed by previously constructed dies, and which will permit the use of a blade which is as wide as those ordinarily employed in all-metal dies.

We accomplish these objects by providing a series of metal clips which are attached to the edge portion of the core or pattern and which are each provided with a transverse face of sufficient length to permit the attachment theretoof a blade of the desired width by spot welding at opposite sides of the pattern without injury either to the pattern, or to the cutting edge of the blade, which operation may be conveniently performed after the clips have been attached to the pattern. While separate clips seem most desirable, they may also be formed in a continuous strip.

For a more complete disclosure of our invention reference is now made to the following specification, in connection with the accompanying drawing in which:

Fig. 1 is a plan view of a die containing a preferred embodiment of our invention.

Fig. 2 is an edge view thereof.

Fig. 3 is a sectional view on an enlarged scale at line 33 of Fig. 1.

Fig. 4 is a detail perspective view of a form of clip which is employed.

Fig. 5 is a plan view illustrating a modified form of clip.

Fig. 6 is a. sectional view at line 6-6 of Fig. 5.

Fig. 7 is a detail perspective view of the clip shown in Fig. 6 prior to attachment.

Fig. 8 is a view indicating the clips arranged in a continuous strip and Fig. 9 shows a modified form of the clip shown in Fig. '7.

In the drawing Ill indicates a core or pattern of fiberboard, or similar sheet material, of which shoe patterns are usually formed, which have a metal binding and are employed in cutting out shoe parts by hand with a knife, the pattern corresponding in shape to the part which is to be cut from sheet material.

According to our invention we provide a series of clips, each of which consist of a strip of metal bent to form an outer face portion I2 which extends for nearly the width of the blade subsequently to be attached, an inner face portion 13 and M, which is formed by bending the strip reversely at each end of the outer face portion and a flange portion which consists of the two end portions l5, l6 which extend at right angles to the outer face portion and have an aperture l1 extending therethru. Each clip is placed in position with its longer inner face portion l3 against the edge of the plate or pattern Ill, and its flange portion resting on one side of the plate, and is attached thereto by passing a rivet l8 thru the plate Ill and the aperture l1 and heading the rivet against the flange, as shown in Fig. 3. Both end portions of the face portion I 2 are thus securely held against lateral strain. A series of these clips are secured at suitable intervals to the edge portion of the pattern, the number shown being merely illustrative.

A blade 20, consisting of a strip of thin flexible steel having a sharp cutting edge at each edge, is attached by spot welding to the outer face portions of the clips, a weld 2| and 22 being made at each side of the pattern and between the pattern and the cutting edge of the blade as indicated, said 'blade being extended entirely about the pattern and the ends of the blade being connected by spot welding in any suitable manner.

By this arrangement the clips may first be attached to the plate or pattern and then the blade may be attached to the clips by spot welding without injury to the cutting edges of the blade, as the space between each cutting edge and the adjacent side of the pattern is sufficient to permit this operation to be readily performed.

As thus constructed the blade is securely held 2 against lateral strains as both portions of the outer face are securely held by the flanges.

As shown in Fig. 8 the clips may be formed in a continuous strip l4 and provided with attaching flanges l5 at intervals, or two or more clips may be formed. in one piece, as desired.

In Figs. 5, 6 and 7 a modified form of clip is indicated. In this form the outer face portion 24 and inner portions 25 and 26 are the same as previously described. The flange portions 21, 28, are also similar but are extended to form sharp prongs 29 and 30, which are bent at right angles thereto, so that when the clip is attached the prongs or end portions are driven thru the pattern from one side and their end portions are clenched against the opposite side, as shown in Fig. 6.

In this instance the blade 20 is attached by spot welding in exactly the manner previously described, and the construction has the same advantages.

In Fig. 9 a slight modification of the clip shown in Fig. '7 is illustrated. In this instance a single attaching prong 32 is employed, otherwise the construction is the same as before described.

With the above described constructions a blade of the full width of A." may be employed, which will be sufiiciently supported against lateral strains.

We claim:

A die comprising a pattern consisting of a flat plate of fiberous material a pretempered cutting blade having cutting edge portions at its opposite edges and extending about the edge of the plate, means for attaching said blade to the plate comprising a metal clip having an inner face engaged with the edge of said plate and an outer face disposed perpendicularly to the sides of the plate and extending transversely of the plate for a substantial distance beyond both sides thereof and terminating adjacent each cutting edge portion of the blade at opposite sides of the plate, means engaging both sides of the plate for attaching the clip thereto, and a spot weld connection between the blade and outer face of the clip located between each cutting edge portion' of the blade and the adjacent side of the plate.

CHARLES I. STODDARD. ERNEST O. LARSON.

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