US2052063A - Stackable washer and means for fabricating the same - Google Patents

Description

F. D. WENN' Aug. 25, 1936.

STACKABLE WASHER AND MEANS FOR F ABRICATING THE SAME Filed Dec. 16, 1935 Fwvo D WEWA/ INVENTOR.

A TTORNEY Patented Aug. 25, 1936 UNITE s'rn'res PATENT OFFIE STACKABLE wAsnna ANDMEANS FOR FABRICATING THE SAME Floyd D. Wenn, Binghamton, N. Y., assignor to The Brewer-Titchener Corporation, Cortland, N. Y., a corporation of New York 1 This invention relates to a certain article of manufacture and novel die appliances for its economical fabrication on a rapid production scale without material product wastage, and which article may comprise a dished sheet metal washer or the like centrally perforated disc adapted to receive a cooperating rivet. My improvementsthereon are more particularly directed to, the elimination of the burr or ragged edge that is generally formed at the marginal region of a washer aperture while strip stock is being pierced by conventional gang punching appliances, particularly so after the dies have become some? what dull.

In modern practice, such eyelet devices are being extensively utilized and magazine fed in rapid succession by initially stringing a stack of Washers in nested relation upon a rod or the like carrier means. The undermost of such stored Washers is then individually wiped sidewise of said stack by suitable transfer means with the intent to singly withdraw the same in sequence from said stack for placement upon distributed rivets or the like Work pieces. In such associa-. tion, it has been found that the cited burr rough.- ness when uncorrected, is likely to seriously in:- terfere with the desired regularperformance of a magazine feed in that the washers frequently fail to transfer properly and thereby cause oer.- tain of the rivets to be devoid of washers or allow more than one such washer to be fed there.-. to at a time It will be evident that any such disturbances slow up production and in other respects augment fabrication cost when applied for instance, to the making and attaching of. rubber shoe heels or analogous products.

To the end that the cited deficiency maybe overcome, I purposely introduce a special stepin the making of my washer which consists in coining, cold swaging or otherwise reshaping the cited metallic burr around the perimeter of the pierced aperture so as to form a smoothly round.- ed or chamfered edge that will substantially eliminate irregular drag behavior without having to individually transfer or otherwise handle such washer product prior to the final blanking thereof. This aspect assumes importance because of the rapid rate at which it is herein contemplated to simultaneously fabricate substantially perfect washers asregards present'needs by the use of multiple gang agencies that operate in unison upon common strip stock and which agencies are adapted to continuously duplicate such product over a long operating period regardless of normaldie wear .or other minor punchdefects.

My improvements insure that any one such washer will more freely slip sidewise from beneath a stack in order that they may be automatically fed without fail from a magazine carrier without dra ging an additional washer along therewith.

The object of my invention is to provide means for fabricating a washer of the character indicated that shall be laterally stiff at the minof metal requirement and one whose dished cross-sectional profile is preferably so shaped that when centrally pierced with a small cylindrical hole, the last sheared or exterior perimetric edge thereof will by special processing be smoothly chamfered to eliminate the cited abnormal burr drag, all such fabrication steps being completed prior to blanking the respective washer perimeters out of strip stock.

Reference is bad to the accompanying one drawing sheet which is illustrative of a preferred embodiment of my washer device including appurtenances for fabricating the same on an in-. tensive basis, and in which: i

Fig. 1 represents a face view of my improved washer in magnified scale, and Fig. 2 shows a sectional profile thereof taken along line A,A.

Fig. 3 schematically depicts a gang die that may be employed in the making of my washer.

' Attention will first be directed to the article which'may comprise a substantially flat annular brim flange portion Hl made of sheet metal and having a dished medial washer region that is here indented to form conical stiffening faces ll of which the central apex region is shown cylindrically apertured at E2 by the use of a suitable piercing punch. It is preferred to so shape the washer profile as to leave a narrow inner ledge portion H3 contiguous to said aperture. One marginal face of the brim flange may be kept somewhat Wider than its opposed face and which widths are respectively designated WI and W2. The disposition is such that when the conical faces are stacked as indicated by dotted outline in Fig. 2, a small clearance gap [3 may be provided between the brim flanges of consecutive washers.

As will presently appear, the aperture l2 and the brim flange lil are punched out of strip stock in a down stroke. The last sheared uppermost edge of the flange iii is then likely to tear away to some extent and leave a slightly raised perimetric burr M. Said clearance gap i3 affords room for unobstructedly receiving such burr when the conical faces are snugly nested upon a carrier rod or otherwise stacked in a conventional manner. Such adjacent washers may be individually slid axially crosswise of each other without abnormal drag on part of the perimetric burr.

Because the inclined washer faces are snugly nested, the inner dragged burr as represented in ragged outline, is initially formed adjacent to the lower sheared or exterior perimetric edge of the aperture [2 and as such is likely to prove far more troublesome when applied to present purposes. To eliminate the lateral drag effect thereof, I subject the burr l5 in a cold state to a novel coining or the like swaging operation to give said edge a smoothly rounded chamfer having a relatively small radius R. When fabricated thus, my improved washer is freed from all obnoxious burr drag and thus allows of regularly using transfer feed magazines for prolonged periods without encountering operating disturbances such as missing a washer or dragging another along therewith. Heretofore, considerable quantities of completed washers have had to be rejected because of the progressively increasing burr formation resulting from die wear.

It is emphasized that as applied to shoe making machinery and the like automatic devices, the washers needed are usually of a small size ranging between to inch diameter of which enormous quantities are now being marketed. The pierced aperture I2 requires a slender punch whose frail cutting edge is likely to chip, wear or otherwise become defective when operated at a high productive rate. In order to minimize the fabrication cost of such a small article without requiring individual handling, it is preferred to strike my washers out of relatively thin strip stock by the use of gang punch press methods and to correct for any dragged burr defects before finally severing the washer from the strip stock. Such procedure permits the use of inherently simple, high speed gang dies in which the unsevered washer is intermittently advanced from station to station and all pierced or blanked fragments are allowed to freely fall away from the dies by gravity.

As an exemplification, attention is directed to Fig. 3 that'illustrates such processing and which successive steps may readily be carried out simultaneously in multiple punch units of this kind to facilitate rapid washer production. The metallic strip stock 26 is then progressively advanced lengthwise by suitable means between the upper and lower die blocks 2| and 22. The first step thereon may be performed by the indenting punch member 23 having a depending impression tip 24 which cooperates with a tubular lower die 25 to form a conical or the like cross-sectional depression 26 in such stock. This indenting station is not essential and may be omitted.

The next adjacent block members may comprise the piercing punch 27 and its cooperating seated die 28 serving to puncture a small aperture 29 through the apex of the strip depression, the perimeter of said aperture being located wholly within the marginal confines of the dished formation 25. The cited inner burr I5 is likely to be formed on the lower aperture edge by the punch drag, its extent depending upon the prevailing sharpness or other operative condition of the cutters. The next onward gang station is centered in a swaging die of which the upper die member 39 is provided with a socketed projection that seats into the strip indentation 26 while its cooperating lower punch member 3| is equipped with an upstanding tit extension 32 which is sized to snugly enter the potential washer aperture 29 so as to maintain the cylindrical size thereof. This operation serves to crush or upset said burr I5 and bring about a filleting of the lower aperture edge sufficiently smooth to accomplish the desired free slippage of washers, when stacked.

The strip is thereupon advanced to the next die station which comprises a blanking punch 33 and a companion lower die 33 arranged to shear the outer perimeter of my washer as indicated by dotted outline in Fig. 3. The finished washer is allowed to drop through the last named die when it is ready for use, the burred aperture edge having been smoothly coined in the process of making and having required no individual handling to perfect the same. It will be obvious that the outer burred edge may at increased fabrication cost, be struck up or otherwise processed subsequent to the cited blanking operation, although this step is ordinarily not required to meet present needs.

While only a single set of complete die components are illustrated, it will be understood that multiple sets of such dies are usually mounted between a common pair of blocks so as to act simultaneously upon the strip stock 2%). The present instrumentalities provide for a series of different kinds of punches such as 2? and 33 which respectively head down upon their cooperating dies 28 and 34 and these have a reversely mounted punch 3| and an overhead die 30 interposed therebetween. The tit 32 is shaped to pre- Vent contraction in the diametral size of the pierced aperture 29 while the dragged inner burr I5 is being coined around the entire perimeter of such aperture. During this operation, the sheared upper edge of such cylindrical aperture is not deformed while distorting the lower edge thereof and the hole size is maintained to properly fit around a specified carrier rod. In addition, the overall height or finished washer thickness is held to a substantially fixed dimension, irrespective of the initial projection on part of the dragged inner burr l5 that may ensue because of a change in the condition of any one of such multiple piercing punches.

When fabricated in accordance with my teachings, such washers are enabled to slip laterally without undue burr drag and when stacked in a magazine, can be selectively shifted by automatic transfer means with the assurance that not more than one such will be picked up at a time. This aspect assumes commercial importance for the reason that the product to which my washer may be applied, is thereby renered more uniform and free from vexing operating delays While fabricating such completed product on a large scale output basis.

As an article of manufacture, a distinctive structural feature of my washer may be recognized by the comparatively smooth feel that has been imparted to its pierced aperture edge, a characteristic that may more readily be detected by microscopic examination.

When processed as described, the tool upkeep costs may be materially reduced since the same keen cutting edge need not be maintained as compared with a process in which the burr drag has not been corrected; that is to say, without the use of my interposed coining dies 39 and 3|, only the first run batch of conventional washers are likely to have their respective apertures so neatly sheared by newly ground dies as to form no significant aperture'burr 5. The piercing punch 2'! generally being of a small diametral size,the wear of its cutting edge is inherently rapid and-likely to allow a large quantity of washers to be fabricated before a prevailing dull condition is perceived by the press attendant. Byvirtue of my improvements, I am enabled to more than double die production between grindings and provide for effectively usable washers that do not require continuous close inspection. As a result, the wastage by returned unfit washers is reduced to a minimum.

Occasional product inspection is sufficient to check up the performance of my machine, which practice has proven capable of delivering an assured high grade output without need of frequent shut down in which to trim the cutting tools or to replace punches. All such interferences seriously conflict with successful commercial production of a-relatively large quota of usable washers and otherwise vitally restrict the profit margin thereon. By introducing "the cited coining step, the piercing implements need not be kept up to the same exacting standard and a noteworthy betterment in productive results is to be had.

As will be understood by those skilled in this art, the disclosed washer improvements find a wide variety of uses and various structural changesin the details or processing thereof may be resorted to in likewise carrying out my illustrative embodiments, all without departing from the spirit and scope of my invention heretofore described and more particularly defined in the appended claims.

I claim:

1. An article of manufacture comprising a plurality of stackable washers fabricated by blanking the same out of strip stock and of which each washer is provided with a relatively flat brim flange component disposed to circumscribe a centrally dished component that is cross-sectionally shaped into a substantially conical profile having a cylindrical hole pierced axially through the apex region thereof and the exterior perimetric edge of which hole prior to blanking the washer is smoothly chamfered inwardly in a direction away from the apex of such profile, said chamfered edge of each such washer serving to facilitate superficial slippage between adjoining faces when the washers are stacked in nested relation and allowing one of the outermost washers to be singly wiped sidewise of its hole axis relative to the next adjacent washer without abnormal frictional drag.

2. An article of manufacture comprising a plurality of stackable washers fabricated by blanking the same out of strip stock and. of which each washer is provided with a relatively flat brim flange component whose opposite side faces are given different Widths and which flange circumscribes a centrally dished component that is cross-sectionally shaped into a substantially conical profile having a cylindrical hole pierced axially through the apex region thereof and the exterior perimetric edge of which hole prior to blanking the washer is smoothly chamfered inwardly in a direction away from the apex of such profile, said washers when stacked in nested relation leaving a gap between each successive pair of brim flanges and which charnfered edge facilitates superficial slippage between adjoining washer faces to allow one of the outermost washers to be singly wiped sidewise of its hole axis relative to its next adjacent washer without abnormal frictional drag.

'3. A gang press agency for fabricating washers and which agencycomprises a series of stations operated in unison and arranged to successively treat a common strip of flat stock when said stock is intermittently advanced bodily from station to station, such consecutive stations respectively being equipped with different punch and die means for performing the following operations upon said stock in sequence, viz: firstly, piercing a cylindrical hole through said stock and which hole has a burr dragged outwardly away from one edge thereof; then 'swaging to coin the entire perimeter of said one edge and thereby substantially free the burr therefrom; and lastly, blanking a washer out of said stock by shearing the washer perimeter subsequent to coining the hole thereof.

' 4. A gang press agency for fabricating washer having a brim flange and which agency comprises a series of stations operated in unison and arranged te successively treat a common strip of flat stock when said stock is intermittently advanced bodily from station to station, such consecutive-stations respectively providing different punch and die means for performing the following operations upon said stock in sequence, vizi firstly, conically indenting one side face of said stock; then piercing a cylindrical hole in the apex region of said indentation to provide for a potential washer having a burr dragged outwardly away from one edge of said hole; thereupon swaging to coin said one edge and thereby substantially free the burr therefrom; and lastly, blanking the coined potential washer out of said stock by shearing exteriorly around said identation to include a circumscribing brim flange within the washer perimeter.

5. A gang press agency for fabricating washers and which agency comprises three stations mounted in series between a fixed block and a superimposed relatively movable block arranged to successively treat a common strip of flat stock when said stock is intermittently advanced bodily from station to station, each such station being equipped with a punch member and a cooperating die member of which the punch members of the first and last stations are carried by the movable block and the interposed station has its punch member reversely carried by the fixed block for performing the following operations on said stock in sequence, viz: firstly, piercing a cylindrical hole through said stock and which hole has a burr dragged outwardly away fro-m one edge by the piercing thereof; then, swaging to coin said one edge to substantially free the burr therefrom; and lastly, blanking a washer out of said stock by shearing the washer perimeter subsequent to coining the hole thereof.

6. A gang press agency for fabricating washers and which agency comprises three stations mounted in series between a fixed block and a superimposed relatively movable block arranged to successively treat a common strip of flat stock when said stock is intermittently advanced bodily from station to station, each such station being equipped with a punch member and a cooperating die member of which the punch members of the first and last stations are carried by the movable block and the interposed station has its punch reversely carried by the fixed block, the first of said punches serving to pierce a cylindrical hole through the stock on a down stroke of the movable block to leave a dragged burr extending outwardly away from the lower edge of said hole, and which interposed station on the next down stroke serves to substantially free said lower edge of the burr formed while piercing a hole through said stock, and which last station serves to blank a washer out of said stock on the next following stroke, the first and last dies being disposed to allow the respective severed strip fragments to fall away from their respective dies by gravity.

7. A gang press agency for fabricating washers and which agency comprises a series of stations operated in unison and arranged to successively treat a common strip of flat stock when said stock is intermittently advanced bodily from station to station, such consecutive stations respectively providing diiferent punch and die means for performing the following operations upon said stock in sequence, viz: firstly, piercing a cylindrical hole through said stock and leaving a dragged burr extending outwardly away from one edge of said hole, then deforming the entire perimeter of said one edge to free the burr therefrom without deforming the other edge of said hole and thereby maintaining a definite overall thickness for the potential washer irrespective of the extent to which said burr may initially have been left on said one edge; and lastly, blanking the washer out of said stock.

8. A gang press agency for fabricating washers at a high productive rate and which agency comprises three stations mounted in series between a fixed block and a superimposed relatively movable block arranged to successively treat a common strip of fiat stock when said stock is intermittently advanced bodily from station to station, each such station being equipped with a punch member and a cooperating die member of which the punch members of the first and last stations are carried by the movable block and the interposed station has its punch reversely carried by the fixed block, the first of said punches serving to pierce a cylindrical hole through the stock on a down stroke of the movable block and leaving a dragged burr extending outwardly away from the lower edge of said hole, said interposed station on the next down stroke serving by a coining operation to substantially free said lower edge of its burr, the reversed punch of said interposed station being provided with tit means enterable into said hole to maintain the pierced diametral size thereof while the strip is being coined, and which last station serves to blank a washer out of said stock on the next following stroke.

FLOYD D. WENN.

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