Method and tool for roll-clenching eyelets

July 27, 1937.

S. L.GOOKIN

2,087,969

METHOD AND TOOL FOR ROLL CLENCHING EYELETS

Filed Aug. 17, 1936

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Patented July 27, 1937

2,087,969

UNITED STATES PATENT OFFICE

2,087,969 METHOD AND TOOL FOR ROLL-CLENCHING EYELETS

Sylvester Leo Gookin, Quincy, Mass., assignor to United Shoe Machinery Corporation, Paterson, N. J., a corporation of New Jersey

Application August 17, 1936, Serial No. 96,332

Claims. (Cl. 218—14)

This invention relates to the art of upsetting and clenching eyelets, of ductile metal, and more especially to that branch of the art known as roil-clenching. A typical example of roll-clench5 ing an eyelet is disclosed in United States Letters Patent No. 1,976,776, granted October 16, 1934 on an application filed in my name, but in that disclosure the eyelet-receiving materials are hard and rigid. On the other hand, my present inven10 tion is concerned more especially with an improved method of, and improved means for, rollclenching eyelets in a manner to increase their holding power or security in soft materials capable of being stretched, such as leather and textile 15 fabrics.

It is to be understood that the requirements that call for roll-clenching, forbid splitting the eyelets. Consequently the clenching end of an eyelet suitable for roll-clenching must be devoid 20 of nicks or scoring that would cause splitting. Moreover, the conditions permissible and possible in roll-clenching restrict the spread or dilation of the clenching end to a compass so small that if the gripped band of eyelet-receiving material 25 once slips under pulling stress the security of the eyelet is greatly diminished if not virtually destroyed, even though the eyelet and the gripped material may not be actually separated when the first slipping occurs.

Nevertheless, I have demonstrated that the holding power of a roll-clenched eyelet may be increased to a very considerable extent, in soft materials such as those above mentioned, and one aspect of my present invention consists in an 35 improved method of accomplishing that result without resorting to any additional operation or special formation in manufacturing such eyelets.

Accordingly, the invention provides an improvement in methods of upsetting and clenching 40 eyelets which consists in flaring and everting a circular clenching end of the barrel of a ductile metal eyelet to direct that end toward the op: posite end of the barrel, and deforming the rim of the everted annulus at one or more points to 45 develop work-indenting projections on its workengaging edge.

To avoid splitting the clenching end of the barrel the roll-clenching should progress to a considerable extent, and may even be completed, 50 before the rim of that end is deformed to develop the aforesaid work-indenting projections, since, if the deforming occurs at a stage too early in the upsetting process, it may result in splitting the clenching portion during the latter stages of 55 the everting process.. As herein exemplified, no deforming occurs during the first half of the upsetting process, but all the deforming occurs during the second half thereof.

Preferably, and as herein shown, the deforming of the clenching portion is effected by in- 5 denting the rim of that portion radially to develop re-entrant lobes, or corrugations. In the illustrated example, six of these lobes are made at uniform intervals, but the number may be larger or smaller if desired. However, irrespec- 10 tive of their number, at each point where a lobe is made, the rim or work-enaging edge of the clenching end is not only deformed radially but is also projected axially beyond the transverse plane of the non-indented portions. The 15 axial projections thus developed increase the holding power of the eyelet in soft material, provided the eyelet is clenched with a degree of pressure sufficient to embed them in the confronting surface of the work. 20

It is quite probable, too, that the clenched portion of the eyelet derives some supplemental stiffening from the lobar formations and is, for that reason, less likely to be sprung away from the flange at the opposite end of the barrel either 25 when the clenching pressure is removed or when the stresses of use tend to pull the eyelet away from the material in which it has been clenched.

Another object of the invention is to provide an improved tool capable of increasing the holding 30 power of a roll-clenched eyelet in accordance with the method herein set forth.

The clenching tool herein shown is provided with a concave annular groove the surface of which is formed to upset and roll-clench the 35 clenching end of the barrel of an eyelet, and also· provided with a series of convex lobes projecting inwardly from the outer wall of the groove to indent the perimeter of the clenching annulus of the eyelet toward the axis thereof. Although 40 this tool is intended to develop the improved formations in the clenching annulus incidentally to roll-clenching an eyelet it is nevertheless capable of impressing similar indentations into the clenching annulus of an eyelet that has been 45 previously roll-clenched without being indented, and thereby increasing the holding power of the eyelet as an individual step of the method set forth.

Referring to the accompanying drawing, 50

Fig. 1 is an end elevation of a typical unscored eyelet having a circular barrel adapted to be roll-clenched;

Fig. 2 is a side elevation, partly in section, of such an eyelet; 55

2,087,969

Fig. 3 is an end. elevation of a combined punching and clenching tool embodying a novel structural feature of the present invention;

Fig. 4 is a sectional view of such a tool in the 5 plane indicated by line IV—IV in Fig. 3;

Fig. 5 is a side elevation of an eyelet of the type illustrated in Figs. 1 and 2 after being rollclenched by a tool of the type shown in Figs. 3 and 4;

Fig. 6 is a cross-section of an eyelet that has been roll-clenched as shown in Fig. 5, the plane of the section being indicated by line VI—VI; and

Fig. 7 is a sectional view representing a pair 15 of co-operative eyelet-setting tools in the final stage of roll-clenching an eyelet in a work-piece of eyelet-receiving material, the upper tool in this figure corresponding to the tool represented in Figs. 3 and 4.

²⁰ All the figures of the drawing represent the elements as enlarged several diameters in comparison with the magnitude of eyelets and tools commonly used in shoe work. The eyelet represented in Figs. 1 and 2 is typical of eyelets here²⁵ tofore manufactured for roll-clenching. It is made of ductile sheet metal and comprises a barrel 19 of circular cross-section, and a flange II at one end thereof. Since splitting of the clenching end is to be avoided when an eyelet is to be ³⁰ roll-clenched, the barrel of the illustrated eyelet is neither scored, nicked, nor otherwise weakened locally. Accordingly, the clenching end 12 of the barrel provides an uninterrupted annulus of ductile metal all in one plane and capable of being ³⁵ dilated, flared, everted and roll-clenched as shown in Fig. 7 without undergoing interruption of its continuity.

The combined punching and roll-clenching tool represented in Figs. 3, 4 and 7 comprises cer40 tain common and well-known features of construction including a body portion 14, a tubular pilot 15 projecting from the body portion 14, an annular groove 16 in the body portion and surrounding the root of the pilot, and a screw45 threaded shank portion 17 by which the tool maybe screwed into and secured to. an operating plunger 18. The groove 16 provides a concave annular operating surface 26 adapted to flare, evert and roll-clench the end 12 of an eyelet bar50 rel. This tool is bored axially, to provide for punching an eyelet-receiving hole in a workpiece 21 such as a shoe upper, the passageway 22 thus formed enabling the lower extremity of the pilot to co-operate with a solid punch-block 55 (not shown), and providing for the discharge of the punchings through the plunger 18.

The novel feature of the punching and clenching tool consists in a series of lobes 25 formed on the outer wall of the groove 16 and projecting 00 inwardly therefrom. These lobes do not interrupt the circularity of the inner wall of the groove but merge gradually into the groove at its deepest portion as represented in Fig. 4. Consequently, an eyelet in process of being roll05 clenched by a tool having lobes formed and arranged as illustrated, will not encounter the lobes until its clenching end 12 has been flared and turned outwardly by the circular inner wall of the groove 16. However, as the process of ever70 sion progresses and curls the end of the barrel toward the flange ! I, the portions 27 of the barrel that encounter the lobes 25 (see Figs. 6 and 7) will be curled more abruptly than the portions 28 that pass between the lobes and continue 75 to be everted and clenched by the intermediate arcuate segments 26 of the outer wall of the groove. The re-entrant indentations or corrugations 27 thus impressed into the everted clenching portion of the barrel impart a wavy formation to the rim of the clenching portion as rep- 5 resented in Fig. 6. These corrugations stiffen the everted portion.

Moreover, since the curling or everting effect of the lobes 25 is more abrupt than that of the arcuate segments 26, the portions 27 that trav- 10 erse the lobes are projected toward the flange ί I to a greater extent than the intermediate portions 28 that traverse the segments 26. This effect is represented in Figs. 5 and 7. Consequently, when an eyelet is upset and clenched 15 in a work-piece 21 of soft or compressible material such as a shoe upper, as represented in Fig. 7, the corrugations or indented portions 27 will be embedded more deeply in the work-piece than the intermediate portions 28 are, and the 20 security of the eyelet will derive a considerable increase of holding power as a result of these differences in the depth of embedding.

Since the initially circular annulus 12 must undergo a considerable dilation in consequence 25 of being flared and everted, it necessarily becomes thinner in consequence of its transformation (compare Figs. 1 and 6), and the reduction of its thickness is the greater as a result of impressing the corrugations 27 into it. However, ·^;θ the process of forming the corrugations 27 has a hardening effect on the metal and increases the stiffness of the everted portion which counteracts whatever tendency the everted portion might otherwise have to spring back or away ³⁵from the flange 11 when the operating pressure of the setting tools is removed.

Fig. 7 also includes an eyelet-inserting tool 30 of well-known construction provided with a central bore containing a spring-pressed spindle 3! 40 adapted to pick eyelets one by one from a raceway. The tool equipment represented in this figure may be utilized both in foot-power eyeletinserting machines of the non-feeding type, and in automatic high-speed eyelet-inserting ma- 45 chines of the feeding type such as that illustrated and described in United States Letters Patent No. 1,228,768, granted June 5, 1917, on application of P. R. Glass. In a machine of the type disclosed in the patent just mentioned, the 50 upper tool carried by the plunger 18 descends into engagement with a solid punch block on which the work-piece 21 lies. The pilot 15 thus cuts or punches an eyelet-receiving hole in ths work-piece, the pill or chip 32 remaining in the 55 bore 22 of the pilot, whereupon the plunger 13 moves laterally to feed the work-piece and to bring the upper tool into coaxial relation with the eyelet-inserting tool 30. In the meantime, the tool 30 rises to cause its spindle 3! to pick 60 an eyelet from a raceway, and continues to rise until the eyelet is inserted into the work-piece and its clenching end is everted and clenched as represented in Fig. 7.

Although economy of production with respect 65 to developing the corrugations 27 is best served by using the illustrated setting tools to produce those formations incidentally to inserting and clenching the eyelets in the first instance, nevertheless, neither the tool 14 nor the above-de- 70 scribed procedure is necessary to develop the corrugations, and the broader protection sought herein is not to be understood as limited to performing the steps of the method contemporaneously. For example, the corrugations 27 may be 75

2,087,969 developed, and their supplemental holding power obtained, after an eyelet has been roll-clenched in the usual manner heretofore well known.

Assuming that a shoe upper or other workpiece has already been provided with rollclenched eyelets not indented or corrugated as herein shown, the tool represented in Figs. 3 and 4, or a suitable modification thereof, may be brought to bear against the everted or rollclenched annulus to the end that the lobes 25 or their functional equivalents will indent the rim of the clenched annulus at a plurality of points as represented in Fig. 6 and thereby embed the indented portions more deeply into the eyeletreceiving material. This alternative procedure will suffice to make it clear that it is within the scope of the broad principle of the invention to impress the corrugations 27 subsequently to the step of everting and clenching the end 12 of an eyelet barrel. It will also be understood that the utility of the tool represented in Figs. 3 and 4 with regard to developing the corrugations 27 does not require that the lobes 25 perform their special function while an eyelet is in process of being roll-clenched.