US2244223A - Method of finishing metal fasteners - Google Patents

Description

June 3, 1941.-

F. B. SMITHE ET AL METHOD OF FINISHING METAL FASTENERS Original Filed Jan. 27, 1937 ATTORNEYS Patented June 3, 1941 ,F F 1 CE 2,244,223 METHOD or FINISHING METAL FASTENERS Frank -B; Smithe, Douglaston, and Abraham Novick, Flushing, N. Y., assignors to F. L. Smithe Machine 00., Inc., New York, N. Y., a

corporation of New York Original application January 27,1937, Serial No. 122,530. Divided and this application March 14, 1940, Serial No. 323,875

5 Claims. (CI. 51 281) This invention relates to the fabrication of metal fasteners, especially to fasteners of the type adapted to-be affixed to a rear wall of an envelope below an apertured closure flap, and having tongues to be bent up into position to protrude through the aperture in the flap, and then to be bent back into retentive position over the opposite margins of the aperture,

Ihe invention is more particularly concerned with the step of finishing the fasteners while assembled in conventional stack formation as they are sold to envelope manufacturers for application to the envelopes, this finishing step being effective to remove from the edges of the tongues the burr formed thereon in the course of die-cutting or stamping the fasteners bodily from sheet metal.

While this burr may be of slight proportions and not of serious import apparently, it has been found to have sufficient abrasive effect upon the fingers of an operative charged with the duty of bending up a large quantity of the tongues in the course of loading such envelopes, to Wear away the cuticle uncomfortably and even dangerously in the course of a single day.

Under such conditions, it is the general object of the present invention to provide an effective method of reducing this objectionable burr to an extent which deprives it of its abrasive characteristic, and a particular object is to accomplish this burr-reduction as a finishing operation performed continuously upon a large number of the fastener blanks assembled upon the conventional U-shaped wire holder disclosed in U. S. Letters Patent No. 1,827,901, and it may be the final step in the fabrication of the fasteners preparatory to furnishing each such sales unit to a user.

Another object of the invention is to provide means to facilitate the presentation of the aforesaid stacks of fastener blanks for a bufiing operation to reduce the iburrs effectively with a minimum of eifort and skill upon the part of an operative, and .at low cost for the operation; also with optimum accuracy, and without displacing any of the fastener blanks from its relative order in the stack.

This application is a division of co-pending application Serial No. 122,530, filed January 27, 1937 which has matured into Patent No. 2,221,- 885 granted November 19, 1940.

Other objects and advantages of the invention will appear as the description of the particular physical embodiment selected for illustration and description progresses.

In the accompanying drawing, like characters of reference have been applied to corresponding parts throughout the several views which make up the drawing, in which:

Fig. 1 is a view of a schematic character illustrating a boiling means for carrying into effect the method of the present invention;

Fig. 2 is a vertical sectional view taken on the line 55 of Fig. 1;

Fig. 3 is a view similar to Fig. 1 of another modification of the means for carrying the present invention into efiect; and

Fig. 4 is a vertical sectional elevation on the line l--'! of Fig. 3.

In one embodiment of means for carrying the present invention into effect, a couple of buffing wheels B2, B3 of suitable material are caused to rotate about horizontal axes, these buffing wheels being in the same vertical plane (see Fig. 2), which defines a path along which a conventional stack of fastener blanks, designated generally by the reference character S is fed lengthwise in the directionof the arrow i3.

Such a stack may desirably be of the form illustrated in U. S. Letters Patent 1,827,901, granted October 20, 1931, to which reference may be had for a more complete description than it is necessary to include herein; and for the purposes of the present disclosure it will be sufii'cient to point out the general contour and disposition of the fastener blank components it, which are assembled with their broad faces 45 in contact to make up the stack.

Each fastener blank I4 is formed of thin metal, and as is evident from an inspection of the drawing, the blanks are cross-shaped so that opposed re-entrant angles occur at the junctions of the body portions 2 and 3 with the arms l and 5.

For the .purpose of maintaining a multiplicity of these blanks in orderly assembled relationship for shipment to envelope factories, and for handling in such factories, provision is made of a staple-like member Br having parallel legs 7 and v 8 thereof disposed in opposite re-entrant angles of the blank stack so as to embrace and interfit with the blanks.

This staple-like holding member may be of considerable length, and the legs 1 and 8 are bendable to a limited extent; extension beyond the stack Where provision is made of a holding plate 9 and a locking plate Iii, both of which are impaled upon the said projecting portions to maintain the stack against separation from, or

and :1: respectively; so that the invention pro-' vides for such disposition of the stacked blanks that the edges 4:1: and 5:0 are presented in salient position for the action thereon of the buffing or finishing wheels, as the stackof blanks is advanced past the finishing station. 1

In the embodiment of means to carry the invention into effect, as illustrated in Figs. 1 and 2,

the presentation at the finishing stage F of the blanks l4, assembled upon a U-shaped staple or holder 6:0, as in the aforesaid arrangement of Patent No. 1,827,901, is effected while the wire legs 1 and 8 of the holder retain the straight disposition in which they come from the operation of assembling the blanks H1 in stack form on the staple, and in which straight disposition it is desirable to have them remain after finishing, for storage, transportation and use.

The method of treatment according to the modification illustrated in Figs. 1 and 2 provides for finishing treatment by the buffer wheels B2 and B3 which are arranged in the same vertical plane as that occupied by the tongues or arms 4 and 5, (see Fig. 2), of the blanks [4, as the stack S is advanced bodily from right to left. The leading end of the stack is supported by a guide 56.x and the bodily advancement of the stack is accomplished by means of a screw 34 rotatable in a head H by suitable means, (not shown).

At the time of original assembly of the blanks in stack form upon the staple 6.7:, or thereafter prior to the finishing step, the end retaining members 9 and H) are set in such a position as to leave space for a. certain amount of play of the blanks within the limits of the stack, and the effect is to afford room for each blank to be biased individually away from the contiguous succeeding blank in the direction of bodily feeding movement of the stack, from right to left in the present instance.

This starts with the first stack component, as Mr (see Fig, l), at the time that the left-hand end of the stack passes into the finishing station F and in order that only one blank it may be permitted to emerge into finishing position at a time, spring friction devices N, N are preferably provided, in conjunction with a pair of guides 33 irough which the stack S is led for treatment.

The friction device includes a pair of spring fingers 3i and 32, each fixed upon the troughlike guide member 33 mounted on a suitable support (not shown) and which serve as guides for the stack.

As the latter is advanced, by rotation of the screw 34 in the head H, one blank at a time is pressed forward through the fingers 3 l, 32 and released for the action of the buffing rolls, which cause it to spring across the gap shown, and its rugous edges E are thereby exposed for bufiing.

In another embodiment of the invention, illustrated in Figs. 3 and 4 of the drawing, a stack S", comprising a multiplicity of blanks l4 assembled upon a staple or holder 66 substantially as disclosed in U. S. Letters Patent No. 1,827,901,1s presented for finishing at a station F", as by a pair of buffing wheels B t and l35,'the stack of blanks being fed bodily past the station from right to left, by suitable mechanism, not shown.

The lower edges E of the closely assembled blanks l4 composing the stack rest upon a ledge or templet L and are caused to travel in succession over a shoulder C which is so disposed with relation to the bufiing wheel B4 that as the latter is rotated counter-clockwise against the exposed upper edges E of the blanks, (see Fig. 4), the wheel exerts a downward bias against the blanks which becomes effective to displace transversely of the stack each successive blank when its lower edge is fed past the shoulder C. This displacement of each blank is permitted by the nature of the support of the blanks on the staple 66, the elements I and 8 allowing such displacement of individual blanks to the extent indicated by virtue of the slight looseness of the fasteners on the staple, and as the displacement occurs, the leading edge E" of the contiguous undisplaced blank is then exposed to the finishing action of the buffing which is effective to remove the residual burrs or rugosities left by the dies at the time of stamping out the blanks.

When the stack has been fed completely past the finishing station, and the edges E and E" of all of the blanks have been thereby finished, the stack will be then replaced bodily at the starting point in reversed position, top for bottom, and fed through again, for the purpose of finishing the edges E.

From the foregoing, it will be evident that in the operation of the several embodiments of means for carrying the invention into effect, there isinvolved, in each of these, the step of feeding bodily past a finishing station, as F in Figs. 1 and 2, or F" in Figs. 3 and 4, a stack of blanks M assembled upon a staple or holder, as 6:0 or 68, so that the bufing wheels or like finishing members as B2, B3 and B4, B5; in each instance, act upon one or more edges of the blanks M, as E, E, E", etc., to perform the step of removing therefrom the characteristic burrs or rugosities which remain after a die-cutting or stamping operation.

While this removal of a burr from the edges of the fastening tongues or arms 4 and 5 of metal envelope fasteners is the intended use illustrated by way of example, it will be apparent that the invention is capable of application in the continuous finishing, as by polishing or otherwise treating of many different kinds of articles of which a multiplicity may be assembled in stack form,

Furthermore, the several modes of presenting the articles individually for treatment, while preserving-their relative order in their stacks, as by creating a gap in the stack, so that each blank is exposed completely as in the form shown in Figs. 1 and 2; and the mode shown in Figs. 3 and 4 according to which a relatively small sidewise displacemest of each blank in turn exposes the edge, as E", of a contiguous blank for treatmentyare merely illustrative physical embodiments of the idea of means underlying the invention, and indicates the flexibility of the novel method, which may be carried into effect by many other modifications of the means illustrated, these not exhausting the possible physical embodiments of such underlying idea of ments shown, but what we desire to cover by Letters Patent is set forth in the appended claims.

We claim:

1. The continuous method of finishing the raw edges of a multiplicity of stamped sheet metal articles having identical contour and size, While assembled in stack form upon an elongated holder along which they are capable of a limited adjustment; said method including the steps of advancing the stack of articles toward a finishing station, moving the end article of the stack with reference to the next adjacent article while positioned at the finishing station so that a raw edge of the article to be finished is separated from the corresponding edge of the next adjacent article and exposed, finishing such exposed raw edge and advancing the stack of finished articles bodily away from the finishing station.

2. The continuous method of removing burrs from the edges of a multiplicity of sheet metal articles having identical contour and size, while assembled in stack form upon an elongated holder along which they are capable of a limited adjustment; said method including the step of feeding the stack of articles up to; a finishing station, the step of subjecting the edges of a plurality of contiguous articles simultaneously to the action of a rotary bufiing tool adapted to exert thereon a bias tending to displace the articles as they successively pass the station and the step of permitting said bias to become effective to cause the end article of the stack to be displaced with reference to the next adjacent article to thereby expose the burred edge of an article to the action of the buffing tool.

3. The method of finishing the raw edges of a plurality of thin sheet metal articles having identical contour and size, which comprises the steps of arranging the articles in a stack, applying a yielding pressure to the end article of the stack to urge said end article into contact with the next adjacent article, displacing the end article of the stack so as to separate it from the next adjacent article by a free space and subjecting a raw edge of the displaced article to the action of a rotary finishing instrument while maintaining the displaced article in alignment with the stack.

4. The method as set forth in claim 3 in which the displacement of the end article results from the pressure thereon of the rotary finishing instrument.

5. The method of finishing the raw edges of a plurality of thin sheet metal articles having identical contour and size, which comprises the steps of arranging the articles in a stack, applying a yielding pressure to the end article of the stack to urge said end article into contact with the next adjacent article, displacing the end article of the stack so as to separate it from the next adjacent article by a free space and subjecting oppositely disposed raw edges of the displaced article simultaneously to the action of rotary finishing instruments While maintaining the displaced article in alignment with the stack.

FRANK B. SMITHE. ABRAHAMI NOVICK.

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