US2038743A - Die - Google Patents

Description

DIE

c. R. LINbHOLM Filed Sept. 12, 1934 April 28,

Patented Apr. 28, 1936 UNITED STATES DIE Courtney R. Lindholm, St. Louis, Mo., assignor to Independent Die and Supply Company, St Louis, M0,, a corporation of. Missouri Application September 12, 1934, Serial No. 743,704

3 Claims.

This invention relates generally to dies and particularly to a stripping device for dies of the blanking type.

Dies of the blanking type which are largely used in the manufacture of leather goods, such as gloves, and in many other industries, are ordinarily provided with a stripping device so arranged that the cut material, either the cuttings or the blank, is forced away from the cutting edges of the die after the die has penetrated one or more thicknesses of the material to be out. Ordinarily such stripping devices are resiliently mounted so as to be biased in a direction toward the edges of the die. In order to prevent the strippi g device from being forced outwardly beyond the edges of the die some means is ordinarily provided for limiting the outward movement of the stripper so that it is usually held substantiallyflush with the edge of the die. Heretofore various means, such as telescoping members, chains and the like, have beenv provided for this purpose.

The use of chains as the means for limiting the movement of the stripper with such dies has been attended with considerable difficulty for various reasons. In the first place, the chains are subject to considerable stretching so that after a relatively short period of use the stripper may be permittedto extend outwardly beyond the cutting edge of the die and thus interfere with its proper functioning. Moreover, the chains do not lend themselves to adjustment within short ranges, but such adjustment as is permitted is limited by link lengths and consequently proper adjustment of the stripper is difiicult to obtain. Moreover, fouling of the chains with adjacent parts is not.

uncommon.

The object of the present invention, generally stated, is to provide a die of the character referred to with a stripper limiting means which is not subject to the objections above mentioned.

A further object of the present invention is to provide a stripper limiting means for a die of the character referred to which is formed of a strip of flexible, substantially non-stretchable, fibrous material.

A more specific object of this invention is to provide a stripper limiting means for a die of the character referred to which is formed of textile webbing.

Other objects will become apparent to those skilled in the art when the following description is read in connection with the accompanying drawing, in which:-

Figure 1 is a perspective view of a die for a glove thumb having a stripper constructed and arranged in accordance'with the present invention;

Figure 2 is a longitudinal section taken along line 22 of Figure l, and illustrating more in de- 5 tail the stripper operating mechanism of the die;

Figure 3 is a cross sectional view taken along line 3-3 of Figure 1.

In accordance with the present invention dies of the blanking type which are ordinarily pro-- 10' vided with aresiliently mounted stripper arranged to be biased toward the cutting edge of the die so as to eject therefrom the cut material, either in the form of cuttings orblanks, may be provided with a means in the form of a strap for limiting l5 the, movement of such stripper toward th cutting edges of the die which strap is sufliciently flexible to permit a wide amplitude of movement of the stripper without fouling, is non-stretchable so that the adjustment' of the stripper rela- 26 tive to the cutting edge remains the same, even after a longperiod of use and is such as to lend itself with facility to adjustments of any desired extent. In accordance with the present invention, cotton webbing may be employed for this purpose. 7

Referring. now particularly to the drawin there is illustrated in Figure l a. blanking die of a shapesuitable for use in cutting blanks of a shape and size for the making of thumbs of gloves and.

the invention .will be described with particular reference. to such die, although it is to be understood that the invention is not limited to any particular type of configuration of die.

Asvshown in Figure l, the die may comprise a blade i having a cutting edge 2 extendingem tirely therearound. On the interior of the cutting edge 2 and in slightly spaced relation thereto is a stripper, plate 3 arranged for movement axially of the die, but normally biased into a 40 position where it is. substantially flush with the cutting edgeon the die, as shown, so that upon release of the pressure of the device in which the die is operated, the stripper plate 3 is effective to eject blanks from the interior of the die, itbeing understood that in usual operation the die may penetrate a number of thicknesses of material, such as leather, at one blow.

As clearly shown in Figures 2 and 3 across the top of blade I that is to say the edge remote from the cutting edge 2, is a top plate or cross piece 4 which. may be suitably connected to the blade l as by screws 5 threaded into bosses 6, the latter being integral with blade I. Extending upwardly from blade 4 is a plurality of studs 1, two being shown but it being understood that any number may be provided, over'each of which is placed a coil'spring 8. The other end of the coil spring I 8 may be seated against the inside of the stripper plate 3 and, as shown, may be inserted in suitable cups 9 in order to prevent slippage of the spring on the stripper plate. It will be apparent that the action of springs 8 is to bias the stripper plate 3 toward the cutting edges 2.

In accordance with the present invention, means is provided for limiting the outward movement of stripper plate 3 under the action of spring 8, and for this purpose one or more strips 'of a flexible, non-stretchable material, such as. "cotton webbing, may be provided. The strips of webbing I I are suitably secured by any desirable clamping means to the top plate or cross piece 4 and are likewise secured to the inside of the stripper plate 3.

Referring particularly to Figure 3, it will be I :observed that the strips ofwebbing I I are folded over at their respective ends I2 and I3 so as to' provide a double thickness against which the clamping device can operate. A suitable form of clamping device is illustrated in the drawing and may comprisea bolt I0 extending through strip- 'per plate 3 and through both thicknesses of the strip ofwebbing II. Above the folded webbing may be provided a wa'sher [4 illustrated inthe form of a plate which, if desired, may be provided on the underside with teeth or serrations which may take more, firmly into the webbing,

and upon the end of bolt I3 may bethreaded a nut I5 drawn down sufficiently tight to prevent the webbing from slipping. Similar clamping arrangements may be provided at the lower ends,

a of the respective strips of webbing for clamping the same against the top plate 4. Such an arrangement permits the length of strip I I to be readily adjusted 'so'that the movement of the stripper plate 3 may be limited to any desired extent ,which may be, for instance, substantially flush with cutting edges of the blade I.

Suitable means such as a rib I5 may be provided on the exterior of blade I for connecting 'where it willbe noted that the stripper 3 has moved substantially one-half of the depth of the die. This movement is against the force of spring 8 so that when the pressure of the operating device is relieved, springs 8 expand and. force stripperplate 3 back outwardly toward the edges 2 of the die, thus ejecting the cut blanks from the interior of the die. When the die has pene-q trated the various thicknesses to be cut, it will be observed that thestrips of webbing II have been bowed outwardly and in theembodiment illustrated, as shown particularly in Figure 3, the respective strips of webbing are so connected to the clamping device thatthe one on the left bows toward the left, and the one on the right bows toward the right so that they are entirely free of each other and there is 'no' tendency for foul mg.

of springs 8 limit the outward movement of the stripper to any desired position.

From the foregoing description it is'apparent that the present invention accomplishes its objectsand that a stripper limiting device is provided which, although flexible enough to permit an extreme amplitude of the stripper is, nevertheless, substantially non-stretchable so that an adjustment once made continues for along period of time and isv also capable of being adjusted within exceedingly fine variations. It is further apparent that'the-invention is applicable to various typesand configurations of dies and it is to be distinctly understoodltherefore that the in: vention is not limited to the specific details of structure which have hereinbefore been set forth. It is to be distinctly understood, therefore, that such modifications and the use of such individual features and sub-combinations of features as do 'not depart from the spirit-of this invention are,

although not specifically described herein, contemplated by and within the scope of the, ap-

pended claims. I V a 1 Having thus described the invention, what-is claimed is: r

1. In combination, a blanking die having a These strips, however, when the stripper plate has been forced outwardly under the action stripper cooperating therewith'to removethe cut material from the edges of the die, resilient means forcing said stripper; outwardly ofsaid die,

a continuous flexible non-stretchable band limiting the outward movement of said stripper,-an d means for adjusting said band in order accurate-:

ly to position said stripper. a, 2. In combination, a blanking die having astripper cooperating therewith to remove the cut means forcing said stripper outwardly of said die,

a continuous flexible non-stretchable bandlimit material from the edges of the die, resilient into stripping position, and a strap of flexible but,

substantially non-stretchable material connecting saidstripper with said die for limiting the movement of said stripper with' respect to the cutting edge of said die.

' COURTNEY R. LINDHOLMQ, V

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