US2421419A - Sole treating apparatus - Google Patents

Description

3 Sheet-Sheet l r w W w d M II n H m H e CYA z 0 6 W .m 2 v w a i 1J :MFLQ .1 0% o HI 1/1 a 4 1/. M 3/ EMKW Q June 3,1947. .uc. HARDIE SOLE TREATING APPARATUS Filed Dec. 22, 1945 Inventor John Cfiizrdz'e B has Attoi-ng J. C. HARDIE 3 Sheets-Sheet 2 a V H) SOLE TREATING APPARATUS Filed Dec: 22, 1945 &

June 3, 1947;

I J. c. HARDIE 2,421,419

SOLE TREATING A PPARATUS Filed Dec. '22, 1945 3 Sheets-Sheet 3 Z Y M June 3, 1947.

Inventor Johrz C. Haraz'e B his Attome Patented June 3, 1 947 UNITED STATES PATENTOFFICE SOLE TREATING APPARATUS John C. Hal-die, Brockton, Mass., assignor to United Shoe Machinery Corporation, Flemington, N. J a corporation of New Jersey Application December 22, 1945, Serial No. 636,768

3 Claims. 7 1

This invention relates to apparatus for treating soles and more particularly to apparatus for preparing a sole prior to the sole-laying operation in which it is assembled with a lasted upper. This application is a continuation-in-part of application for Letters Patent'of the United States, Serial No. 553,312, filed September 9, 1944, which is in turn a division of application Serial No. 506,512, filed October 16, 1943.

In the manufacture of mens welt shoes it is customary to assemble the outsole with the lasted and welted upper in a sole-laying machine. In so doing, the outsole blank provided with a suitable adhesive on its flesh surface isplaced in the machine in a flat condition on a suitably shaped pad, after which pressure is applied adhesively to secure the sole to the shoe bottom. The pad is so shaped that the sole conforms generally to the shape of the last bottom. The sole is then rounded to the proper contour if it has not previously been so rounded, after which it is stitched to the welt.

This method is satisfactory in the manufacture of welt shoes the soles of which are of only moderate thickness and not excessively stiff. However, in the cases in which very thick outsoles are employed, the resistan :e of the leather to the deformation required to shape it to the bottom of the last is so great that the leather tends to resume its initial flat condition after the shoe is removed from the sole-laying machine, so that the marginal portions of the sole sometimes pull away from the welt. Accordingly, when the marginal portions'of the sole and the welt are drawn tightly together during the outsole-stitching operation, since the soleis usually stiller than the welt, the latter is drawn away from the upper and down to the sole, causing what is known in the trade as a grinning seam, placing a strain on the inseam by which the Welt is secured to the upper and to the insole, and impairing the appearance of the completed shoe.

To prevent the above condition, it is frequently the practice to preshape the sole in a molding machine to impart the desired contour thereto before the sole-laying operation. If the molds of the molding machine are properly shaped to correspond to the bottom of the last the molded sole will lie close to the welt around the margin when the sole is assembled with the upper. However, if the contour of the molds does not correspond exactly with that of the last bottom, as is often the case inasmuch as it is impracticable to provide diiierent molds-for each size and style of last, additional shaping of the sole in the sole-,

hardened and resists any subsequent attemptto' change its contour. Accordingly, if the contour of the sole does not correspond exactly with that of the last bottom, it may not be possible for the sole-laying machine properly to alter its contour so that it corresponds to that of the last bottom and lies up close to the welt. This is'particular 1y true in the case of extremely thick soles or heavy laminated soles made of two plies of leather or leather and rubber or the like, of the type employed in heavy duty work shoes, army shoes, etc. If, therefore, the contour of the sole,after the sole-molding operation, is such that the margin does not lie close to the welt at all points, the sole may be so hard that it is more difiicult to bring the margin up close to the welt than if the sole had not been treated in the molding machine. Thus, the difiiculties pointed out above in bringing the sole up to the welt instead of bringing the welt down to the sole during the outsole-stitching operation may still be present.

It is an object of the present invention to provide an apparatus for treating an outsole in a manner which overcomes the disadvantages of the usual practices as outlined above. To this end and in accordance with a feature of the invention, the machine includes a pair of cooperating forms, the Work-engaging faces of which are so shaped that the flexibility of a sole placed between them is increased by bending stresses imparted thereto. The forms act on the sole with out exerting any molding pressure thereon which would tend to compress the fibers of the leather in directions normal to the faces thereof and thus harden the sole. During its treatment, the sole is not subjected to any stretching or elongating forces, so that the size of the sole is not altered in any respect. This is of importance, particularly when heavy soles-of laminated material such as soles of leather and rubber are being treated, inasmuch as any stretching of the sole would tend to destroy the bond between the layers of which the sole is formed, this being particularly true when the materials of the different layers have different resistances to stretching. This treatment of the sole insures that it will lie near the welt when assembled with the shoe. Moreover any variations in the contours of the sole and of the shoe bottom due to differences in sizes and styles are readily overcome during the sole-laying operation, inasmuch as the sole is not in the least hardened by compressive forces normal to the sole but rather the resistance of the leather to conformity to the shoe bottom is decreased by this treatment. Thus the sole is readily conformed to the bottom of the last with no heavy strain on any part of the seam, thereby eliminating the possibility of grinning seams.

The above and other features of. the invention will now-be more particularly described by reference to the accompanying drawings and pointed out in the claims.

In the drawings,

Fig. 1 is a side elevation of the head of one form of machine adapted to treat soles in accord\ ance with the present invention;

Fig. 2 is a side elevation, on a larger scale than Fig. 1, of the lower sole-treating form of the machine;

Fig. 3 is a vertical longitudinal section through the upper and lower forms, illustrating their operation-on a sole;

Fig.4 is a section on the line IV-IV of Fig. 3;

Fig; 5 is a section on the line V--V of Fig. 3;

Fig. 6- is a perspective view of a sole after it has beentreated by the machine;

'Fig. 'Z 'isasection on the line VII-VII of Fig. 3, and

Fig. 8 is a frontelevation of the lower form.

'Themachine illustrated in Fig. '1, except for the sole-engaging members, is substantially like that shown; in Letters'Patent of the United States No. 1,003,971, granted September 26, 1911, on an application filed in the name of A. A. Ball, J-r. As illustrated therein,- the machine comprises a crosshead Hl carrying on its under side an upper fixed form I 2 arranged to be adjusted heightw-ise with respecttothe crosshead byan adjusting wheel M -to accommodate soles of varying thicknesses. Alower form I6 is carried on a slide It ina crosshead 20. This crosshead is guided for vertical movement on rods 22 and is reciprocated vertically through a toggle mechanism, including a toggle l i-nk it, thereby to move the lower form F6 upwardly toward the form 12. Transverse movement of'the form 16 tocarry it into alinement with the upper form I2 is effected during the'up'ward movement of the crosshead 20 by an arm-"2'5 carried by the toggle link 24 and carrying a roll 28 engageable in a cam slot 30 in a lever 32 pivoted at 34 to the crosshead 28. This lever-is also connected by a link 3'6 to the slide l8. As the toggle is straightened to force the lower crosshead 2,6 upwardly, the roll 2-8 acts upon the lever 32 'tomove it in a clockwise direction, thereby-moving the slide It to carry the form IG-into-a-linement with the form [2. For a more complete explanation of the construction and operation of the machine as whole, reference may be made to the aforementioned patent.

"The shapes of the for-ms l2 and 16 are illustrated-more particularly-in Figs. 2, 3, 4,5, '7 and 8. As shown in-Figs..2 and "3, the lower form 16 is sharply curvedlengthwise from the ball line 4'9 to the shank portion 42 and also toward the forepart 44; and the upper form 12 is correspondingly shaped, as shown in Fig. 3. Accordingly, when a sole 8 is acted upon by the forms the leather orma'teria'l of which the sole is made is bent longl'tudi-nally" from the ball line to the forepart and from theball line 'rearwardly to the shank portion. The sole that is illustrated as being treated herein is a sole for a mans shoe, and it will be apparent'that the bending of the sole is considerably greater than that required in the finished shoe. "This excessive bending of the sole displaces the fibers of the leather, the bending stresses thereby weakening the leather and increasing its flexibility.

As shown in Figs. 4, 7 and 8, the forepart of the lower form [6 has a substantially fiat transversely extending central portion 48 which extends from the vicinity of the ball line 40 (Fig. 2) to the toe end of the form. This central portion 48 is flanked by downwardly sloping sides 50 forming with the flat portion 48 angles 52 about which the sole is bent sharply as shown in Figs. 4 and 7 when the lower form I6 is moved into operative relation with the upper form 12. The upper form 12 is substantially complementary to the lower form except that the surfaces 54 diverge with respect to the surfaces 50 so that when the lower form is moved upwardly into the position shown in Figs. 4 and 7 to act on the sole no compressive forces will be applied, particularly to the marginal portions, normal to the faces of the sole. Thus the fibers are uncompressed in directions normal to-the faces of the sole and consequently there is no hardening of the sole such as occurs in the usual sole-molding operation. The machine isadjusted so that when the lower form I6 reaches its uppermost position it is spaced from the upper form 12 a distance equal to that of the thickness of the sole blank prior to its being operated upon.

The shank portion of the forms in transverse section are shaped as shown in Fig. 5 and these forms present sharply curved central portions 56, 58 which are flanked by substantially flat portions 68, 62 providing sharp angles 64 about which the sole is bent and weakened so that the marginal portions-of the sole at the shank portion are readily conformable to the "bottom of the last.

From the above it-will be seen that the sole is subjected to excessive bending forces longitudinally in the forepa-rt' from the ball line. to the shank as well as toward the toe end causing displacement of the fibers of the leather and accordingly the sole is rendered more flexible by the bending stresses imparted thereto. This is accomplished without applying compressive forces normal to the faces of the sole by proper preadjustment of themachine so that the benefits obtained by the excessive bending of the sole and weakening of it are not nullified by hardening the sole as would be the case were it compressed. The sharp transverse bending of the sole along the outer edges of the central flat portion 48 so displaces the fibers and weakens the sole that the marginal portions of the sole are readily brought up to the welt in the sole-laying operation. The divergency of the adjacent faces of the forms at their outer portions as indicated clearly in Figs. 4, 5 and 7 eliminates any possibility of compressing the sole along the marginal portions even if the apparatus should be slightly out of proper adjustment.

The sole S which is illustrated as undergoing treatment herein comprises a heavy rubber outer layer 0 to which is cemented a leather inner layer M, the two forming a laminated outsole. The resilience of the heavy rubber layer acts to return the sole partially toward its original condition so that the shape of the final product after removal from the machine, as illustrated, does not correspond exactly to that of the forms. The marginal portions of the sole extending around the forepart and along both sides of the shank are displaced heightwise from the mid portion of the sole, and accordingly will lie up close tot-he welt when the sole is assembled with a lasted upper. Any discrepancies between the contour of the sole and that of the bottom of the last are readily corrected by the sole-laying machine, inasmuch as the leather has been weakened around the marginal portion, and accordingly when the shoe is removed from the solelaying machine the marginal portion thereof lies close to the welt and it is unnecessary for the Welt to be drawn downwardly during the outsole-stitching operation. Suitable means, not shown, may be provided for locating the heel end of the sole on the lower form. However, the sole is otherwise free of the forms so that the treatment of the sole is effected without any elongagation thereof, which would take place were both ends of the sole clamped against the lower form prior to upward movement of the form. This is of importance, particularly in the treatment of laminated soles, in order to minimize any tendency to weaken or destroy the bond between the layers of the sole.

It will be understood that the present invention permits the treatment of soles of different sizes and styles without the necessity of providing separate forms for each size and style, since the objective of the invention is to increase the flexibility of the soles and not to mold them to an exact shape.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for treating soles comprising a pair of forms arranged to act on opposite sides of a sole along its forepart, each of said forms be ing sharply curved longitudinally in the forepart and having a substantially flat transverse central portion extending substantially from the ball line to the toe end thereof, said central portion being flanked by marginal portions sharply inclined relatively thereto, the lengthwise curvatures of 6 said forms and the inclinations of said marginal portions with respect to the central portion being such that the flexibility of a sole treated between the forms is increased by bending stresses imparted thereto.

2. Apparatus for treating soles comprising a pair of forms arranged to act on opposite sides of a sole along its forepart, each of said forms being sharply curved longitudinally in the forepart and having a substantially flat transverse central portion extending substantially from the ball line to the toe end thereof, said central portion being flanked by marginal portions sharply inclined relatively thereto, the lengthwise curvatures of said forms and the inclinations of said marginal portions with respect to the central portion being such that the flexibility of a sole treated between the forms is increased by bending stresses imparted thereto, the opposed marginal portions of said forms diverging laterally from the central portions to the outer edges.

3. Apparatus for treating soles comprising a pair of forms arranged to act on opposite sides of an outsole, each of said forms being sharply curved longitudinally in the forepart and laterally in the shank portion, the foreparts of said forms having substantially fiat transverse central portions extending substantially from the ball line to the toe flanked by marginal portions sharply inclined relatively thereto, the opposed marginal portions of the forms diverging outwardly from said central portions, the longitudinal curvatures of the foreparts of the forms, the lateral curvatures of the shank portions and the inclinations of the marginal portions of the foreparts relatively to the central portions being such that the flexibility of a sole operated upon between said forms is increased by bending stresses imparted thereto.

JOHN C. HARDIE.

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