US2900649A - Methods of making platform shoes, the parts of which are united by a reinforced seam - Google Patents

Description

Aug. 25, 1959 E. QUINN 2,900,649

METHODS OF MAKING PLATFORM SHOES, THE PARTS OF WHICH ARE UNITED BY A REINFORCED SEAM Original Filed April 26, 1955 3 Sheets-Sheet l Inventor Edward Quin 1 9 E. QUINN 2,900,649

METHODS OF MAKING PLATFORM SHOES, THE PARTS OF WHICH ARE UNITED BY A REINFORCED SEAM Original Filed April 26, 1955 3 Sheets-Sheet 2 dward 9 Aug. 25, 1959 E. QUINN 2,900,64

METHODS OF MAKING PLATFORM SHOES, THE PARTS OF v WHICH ARE UNITED BY A REINFORCED SEAM Original Filed April 26, 1955 5 Sheets-Sheet 3 Invenf or' Edwa d Q METHODS OF G PLATFORM SHOES, THE

PARTS OF ill UNITED BY A REIN- FORCED SEAM Original application April 26, 1955, Serial No. 503,904.

Divided and this application October 18, 1956, Serial No. 616,666

1 Claim. (Cl. 12-142) This invention relates to an improved form of shoe construction and more particularly to methods of sewing together the parts of platform shoes. The subject-matter of the present application has already been disclosed in a parent application for United States Letters Patent, Serial No. 503,904, filed April 26, 1955, in the name of the present inventor and of which the present application is a division. The parent application, in addition to the present invention, also discloses a novel chain-stitch machine and a machine and method for forming cement bonded seams, the latter machine and method being the subjectmatter of another divisional application, Serial No. 626,354, filed December 5, 195 6, in the name of the present inventor.

Platform shoes have heretofore been subject to certain difiiculties inherent in their construction. A conventional platform shoe is assembled by connecting together a sock lining, an upper and a platform wrapper strip by means of either one seam or two seams successively inserted in parallel relation. The assembly may be accomplished by joining the sock lining to the upper on a last and then attaching the wrapper while the sock lining and upper are still on the last. Alaternatively, the sock lining, upper and wrapper strip may be sewn together by either one or two seams without the use of a last and then a last inserted for subsequent operations. A platform is thereafter spotted on the sock lining, and the wrapper strip is lasted under crosswise tension over the edge of the platform which, after the removal of the last, provides the necessary configuration to the shoe. After the platform is in place and the wrapper strip lasted over, an outsole is attached as by cement, for example, to complete the shoe.

The seam by which the wrapper strip is united to the upper and sock lining is subject to special stresses during the lasting operation and also during subsequent wear. Due partly to such stresses and partly to other causes the results of inserting a wrapper attaching seam are not entirely satisfactory in conventional platform shoes. One common defect in such seams is called grinning and consists in exposure of the thread in a completed shoe between the upper and the wrapper. A grinning seam exposes the thread, so that premature deterioration occurs and gives the shoe a roughly finished appearance which may hamper its sale. Also, afgrinning seam may allow moisture and other foreign matter to enter the shoe, thus impairing the comfort of its wearer.

Another defect of the conventional platform shoe construction is that the attaching seam may sag between perforations through which its thread penetrates the shoe parts, The sagging is caused by the crosswise lasting tension and produces a very uneven or saw-tooth fold line in the edge of the platform whether the seam is of the chain or lockstitch type. This defect in conventional shoes is so objectionable that many remedies have been tried to overcome it. One such remedy is shown in United States Letters Patent No. 2,428,431, granted October 7, 1947, upon an application of E. E. Murphy. The remedy shown therein in Figs. 4 and 5 consists in the 2,990,649 Patented Aug. 25, 1959 "ice use of a filler strip over which the platform cover is lasted. This expedient, although structurally sound, is not entirely satisfactory because the application of the filler strip to the wrapper is an added operation which increases materially the cost of manufacture. Such increased cost is especially undesirable in platform shoe construction, which is generally employed in inexpensive snoes.

An inherent difficulty arises from the fact that in a platform shoe, the configuration of the finished shoe is dependent upon proper insertion of the seam by which the platform wrapper is attached to the body of the shoe and to which stress is applied when the wrapper is lasted over the platform, and thereafter during wear. If the thread of this seam breaks, the seam may soon unravel or may easily loosen causing the shoe to lose its shape, thereby shortening its useful life. One expedient which is employed to overcome this latter inherent difficulty consists in applying small intermittent deposits of an adhesive on the seam in a series of dabs spaced apart along the length of the seam. Such dabs not only are ineffective because they allow the seam between them to become unraveled or loosened, but also tend to produce bunches and otherwise objectionably mar the regular appearance of the fold line of the wrapper strip over the platform edge.

It is an object of my invention to provide a novel platform shoe construction in which the shoe parts in the area of the seam connecting the wrapper strip to the upper and sock lining are backed and reinforced to eliminate separation of the parts and consequent exposure of' the thread. Another object is to provide an even fold line in the wrapper strip at the edge of the platform in a platform shoe to improve its appearance and saleability without significantly adding to the cost of manufacture. Still another object is to lock the thread of the wrapper connecting scam in place in such a manner that unraveling will be prevented and little or no damage to a shoe will result from breakage of the thread in the wrapper connecting seam.

The foregoing objects of my invention are attained in a novel platform shoe construction in which the seam which connects the wrapper strip to the upper and. sock lining is covered by a continuous ribbon of cement. The width of the ribbon is uniform throughout its length and suificient to form a support for the wrapper strip fold spaced slightly from the line of the seam. The cement which is formed by an adhesive deposit is of sufiicient thickness to mask completely the irregularity of even the chain side of a chain-stitch seam. My methods are especially useful for operating upon a shoe in which a single chain-stitch seam is employed to connect the wrapper strip, the upper, and the sock lining, the seam being embedded on its chain side in the adhesive agent during the formation of the seam in an area beyond the point of needle operation. By applying and relaxing tension of the thread of the seam, according to a feature of my invention, it is possible to effect a more intimate bond between the thread and the adhesive agent than has heretofore been possible. It will be appreciated, however, that a shoe may be substantially improved by the practice of the teachings of my invention without the use of the machine which will be generally described herein or without depositing the adhesive during the formation of the seam.

The foregoing and additional objects, advantages, and novel features of my invention including methods of making the shoe outlined above will be more clearly under; stood and more fully appreciated from the following detailed description of an illustrative embodiment and procedures taken in connection with the accompanying drawings, in which:

Fig. 1 is a view taken in transverse section of a shoe made in accordance with my invention;

Fig. 5 is a plan view of an area around the sewing point showing the work-feeding work support and adhesive-depositing nozzle of the machine of Fig. 3.

An illustrative shoe construction, according to my invention is shown in Fig. 1, and includes an upper connected to a sock lining 12 and to a wrapper strip 14 by a seam 16. The shoe is stretched over a last 18 and a platform 20 is spotted on the sock lining within a pocket formed by the strip 14 which is lasted over the edge of the platform and cemented to its lower surface. An outsole 22 is attached to the bottom of the shoe, as by cementing.

The seam 16 is covered by a ribbon of hardened cement 24 of uniform Width and thickness which serves as a backing and reinforcement over which the strip 14 is folded at the edge of the platform. The cement ribbon 24 is formed by .a deposit of an adhesive agent compounded of a rubber solution with an aromatic solvent, such as toluol, a composition which is compatible both with the material of the shoe and with thread, either of natural fiber or of a synthetic, such as nylon. The ribbon has sufiicient stiffness to insure that the wrapper strip 14 is pressed against the upper of the shoe at some distance above the seam 16 rather than being creased along the seam line thereby avoiding a grinning seam. The adhesive agent is applied to the scam in snfficient thickness and has the necessary viscosity at the time of application to mask completely the chain side of the seam and to provide a filler between the thread and the wrapper strip. By utilizing a chain stitch seam in which the stitches are progressively tightened by applying and relaxing tension on the thread, the resultant motion of the thread massages its fibers into the adhesive and carries a quantity of the adhesive into the needle perforations. This quantity of adhesive within the perforations not only improves the bond between the thread, eventually hardened'cement and shoe parts but also guards the thread against exposure and consequent deterioration in an area where conventional platform shoes are most vulnerable.

A Wilcox and Gibbs type sewing machine arranged for conveniently inserting cement-bonded seams in platform shoes and other articles, is fragmentarily shown in Fig. 3, but more fully described in the above-identified parent application to which reference may be had for details to supplement the following brief description: The illustrated machine comprises work-feeding and clamping devices which co-operate with stitch-forming instrumentalities, including a needle 26 and a looper 28, the latter of novel form and mode of operation. The looper 28 is formed in such a manner that once it engages a needle loop and enchains it with the previous loop, tension is applied to the thread for a brief interval and then relaxed for the remainder of the revolution of the looper. This tightens the seam progressively along its length and also causes the thread fibers to be massaged into the adhesive agent deposited beyond the point of needle operation. The adhesive agent is deposited on the seam by a nozzle 30 mounted on a feeding work support 32 shown in Figs. 3 and 5., The nozzle 30 is in communication through suitable tubing with an adhesive 4 feeding device, indicated at 34, which is actuated by connection with the work-feeding mechanisms of the machine. The adhesive feeding device includes a novel disposable cartridge 36 from which the adhesive is conveniently dispensed. Means actuated by a handle 38 is provided for quickly inserting a new cartridge into the feeding device when the supply in the old cartridge is exhausted and a valve 40 is connected to a treadle which controls the starting and stopping of the machine for cutting off the flow of adhesive when the machine is stopped. In addition, the adhesive feeding device is equipped with a selectively operable lever for rendering the adhesive feeding inactive when an adhesive free seam is to be sewn on the machine. The adhesive agent is fed from the cartridge 36 by a screw-propelled piston. The motion of the screw-propelled piston which forces adhesive from the. cartridge is arrested automatically to prevent damage to the feeding device when the supply of adhesive agent is exhausted.

When it is desirable to connect together the sock lining 12, the upper 10 and the wrapper strip 14 by a single seam, an automatic wrapper strip pilot guide, such as that shown in Fig. 4, greatly facilitates the sewing operation. In the illustrated guide, which is similar to that disclosed in United States Letters Patent No. 2,705,464, granted April 5, 1955, upon application of Fred C. Eastman, the wrapper strip is engaged between a pilot roll 42 which revolves about a fixed axis and a presser roll 44 mounted on a spring-pressed carrier. When the roll 44 presses the wrapper strip against the pilot roll, the strip is automatically directed into the sewing point without the attention of the operator except for the insertion of a new strip upon starting the sewing of a new shoe.

The foregoing brief description of a machine, which is suitably arranged for producing cement-bonded seams in shoes is not to be taken as a limitation of the invention, since it will -be readily appreciated that my methods may be carried out either by hand or by machines of other types.

Having thus described in detail a shoe embodying the invention and procedures for its manufacture, what I claim is:

The method of making a platform shoe comprising the steps of sewing a sock lining, an upper, and a platform edge cover strip with a chain-stitch which includes depositing an adhesive agent in a continuous ribbon on the chain side of the seam beyond the sewing point and intermittently applying and relaxing tension on the last formed loop of the seam, whereby the adhesive agent is massaged into the thread as the latter is introduced partially into the needle perforations of the seam whereby .the adhesive agent after application will harden and reenforce the seam and provide a backing for supporting the cover strip.

References Cited in the file of this patent UNITED STATES PATENTS 1,673,784 Groover et al June 12, 1928 1,985,202 Bunker Dec. 18, 1934 1,986,723 Goddu Jan. 1, 1935 1,989,902 Westling Feb. 5, 1935 1,992,968 Sherman Mar. 5, 1935 2,008,916 Burgio July 23, 1935 2,065,786 Ayers Dec. 29, 1936 2,289,335 Ayers July 14, 1942 2,439,900 Murphy Apr. 20, 1948 2,621,426 Palmieri Dec. 16, 1952

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