Stitchdown Footwear And Method Of Manufacture

Abstract

A stitchdown shoe and a method of manufacturing a stitchdown shoe is described. The footwear upper is first prefitted so that it is coextensive with the sole or midsole to which the upper is being attached. The outwardly turned bottom portion of the prefitted upper is cemented to the sole or midsole and then stitched to the sole or midsole using a simple stitching machine.

Description

This invention relates generally to an article of footwear commonly known as a stitchdown shoe and to a method of manufacturing a stitchdown shoe.

A stitchdown shoe is one in which the bottom portion of the footwear upper is turned outwardly and the outwardly turned portion is stitched directly to the midsole of the shoe. The outwardly turned bottom portion forms a flange about the periphery of the upper which is approximately a quarter of an inch wide. A heavy stitch is sewn about the entire flange connecting the upper to the midsole.

Heretofore, the method of manufacturing a stitchdown shoe required that a shoemaker's last be maintained within the shoe during the entire manufacturing operation. Footwear constructed in this manner is commonly referred to as lasted footwear. The first step in manufacturing these lasted stitchdown shoes is to attach a midsole to the last. This is usually accomplished by nailing or stapling the midsole to the last in such a way that the midsole may be removed from the last after the manufacturing operation is completed. The untrimmed footwear upper is then placed over the last. In the next step, the footwear upper is attached to the midsole. This is usually accomplished by a method commonly referred to as thread-lasting. In thread-lasting, a thread laster machine stitches the outwardly turned bottom portion of the upper to the midsole as the machine presses the upright portion of the upper against the last. After the thread-lasting operation the outwardly turned bottom portion of the upper must be trimmed to cut away the excess which is not attached to the midsole. The final step in constructing a lasted stitchdown shoe is to either cement the outer sole to the midsole, or goodyear stitch through all three members: upper, midsole and outsole.

The lasted shoe method of constructing the stitchdown shoe described above has many disadvantages. One disadvantage is that the footwear must remain on the last during the entire manufacturing operation. This means that production runs involving lasted stitchdown shoes cannot begin until the prior production run is completed. Since this is non-economical, it is necessary to have available enough lasts so that a number of production runs can be simultaneously under way. The additional number of lasts required and the heavy duty thread laster machines necessary to perform the thread-lasting operations make the lasted shoe method of producing stitchdown shoes expensive. Another disadvantage of the last shoe method is that it requires many skilled operations, especially in the operation of the thread laster.

A disadvantage inherent in stitchdown shoes constructed according to the lasted method of construction is that the joint between the footwear midsole and the outwardly turned bottom portion of the upper is not water resistant because of the gaps between the stitches.

It is accordingly an object of the present invention to provide an improved method of constructing a stitchdown shoe which eliminates the necessity of using a thread laster machine.

It is a further object of this invention to provide a method of manufacturing a stitchdown shoe which does not require that the shoe be manufactured entirely on a last.

It is a further object of this invention to provide a method of manufacturing a stitchdown shoe which requires few skilled operations and relatively simple and inexpensive machinery.

It is a further object of this invention to provide an improved stitchdown shoe with a strengthened, water resistant joint between the upper and the midsole or sole.

It is a further object of this invention to provide an improved stitchdown shoe in which the upper is joined directly to the midsole, the sole or both the midsole and sole.

Briefly, the method of manufacturing a stitchdown shoe according to this invention includes the following steps. First, the footwear upper is prefitted. That is, the component parts of the upper are sewn together and precut so that the end edge of the outwardly turned bottom portion of the upper is approximately coextensive with the peripheral end edge of the sole or midsole to which the upper is to be joined. In the lasted shoe method of constructing a stitchdown shoe discussed above, the uppers are not prefitted and the excess or unused portion of the upper extending beyond the midsole must be trimmed off after the thread-lasting operation.

In the next step, the toe portion of the upper is gathered to form a pocket for the wearer's toe. This can be accomplished by any of the known methods of forming a toe pocket. One way would be to place a heat-sensitive stiffener in the toe portion of the upper and place the upper in a heated, toe forming mold. A second method of gathering the toe portion of the upper is to use a crimping cord to form a pocket as described in U.S. Pat. Nos. 2,774,087, 2,946,069 and 2,999,323, all of which are assigned to Jo-An Shoe Manufacturing Co., Inc.

The next step in practicing the method of this invention is to apply cement to the underside of the outwardly turned bottom portion or flange portion of the upper and to the peripheral edge of the top surface or the midsole or sole. The flange portion of the upper and the peripheral edge of the midsole or sole are then matched together so that the flange portion of the upper and the peripheral edge of the midsole or sole top surface are mated. The mated portions of the upper and sole or midsole are then fed between two counter-rotating wheels which feed the work and apply pressure to bond the mated portions of the sole or midsole to the upper. The flange portion of the upper is then stitched to the sole or midsole using simple stitching techniques.

In another embodiment of this invention, a ribbed edge is formed about the periphery of the stitchdown shoe. This is accomplished by prestitching a sheath about the outwardly turned bottom portion of the upper and cementing the bottom surface or the sheath to the top side of the sole or midsole. The sheathed outwardly turned bottom portion of the upper is then stitched to the sole or midsole as described above.

The advantages of manufacturing a stitchdown shoe according to the method of this invention are that it is not necessary to use expensive thread-laster machines; it is a lower cost operation because fewer skilled operations are required; and it is not necessary to use shoemaker's lasts during the entire manufacturing operation, except for a brief period of shaping, commonly known as slip or force lasting.

These and other objects and features of this invention will be more readily understood and appreciated by reference to the following descriptions and drawings of which:

FIG. 1 is a perspective view of a stitchdown shoe made according to the method of this invention;

FIG. 2 is an exploded perspective view of a stitchdown shoe made according to the method of this invention illustrating an upper, a midsole and a sole;

FIG. 3 is a cross-sectional view, taken across the width of the toe portion of footwear made according to the method of this invention;

FIG. 4 is a fragmentary, lengthwise cross-sectional view of the toe portion of the footwear illustrated in FIG. 3;

FIG. 5 is a fragmentary, lengthwise cross-sectional view of the toe portion of a second embodiment of footwear made according to the method of this invention;

FIG. 6 is a fragmentary, lengthwise cross-sectional view, of the toe portion of a third embodiment of footwear made according to the method of this invention;

FIG. 7 is a fragmentary, lengthwise cross-sectional view, of the toe portion of a fourth embodiment of footwear made according to the method of this invention;

FIG. 8 is a fragmentary, lengthwise cross-sectional view of the toe portion of a fifth embodiment of footwear made according to the method of this invention; and

FIG. 9 is a fragmentary lengthwise cross-sectional view of the toe portion of a sixth embodiment of footwear made according to the method of this invention.

Stitchdown footwear manufactured according to the method of this invention has superior structural strength in relation to lasted stitchdown footwear because the upper is cemented and stitched to the sole or midsole. Further, the joint between the upper and the sole or midsole in stitchdown footwear manufactured according to the method of this invention is water resistant since the joint is cemented.

In prefitting the footwear upper, the various component parts of the upper are first precut then sewn together so that the peripheral edge 20 of the footwear upper is coextensive with the peripheral edge 22 of the midsole or sole to which the upper is to be joined. The sizes of the various precut components of the upper vary, of course, for various sizes of footwear.

Referring now to FIG. 1, in which a stitchdown shoe is illustrated, it should be noted that any style of upper may be used for the footwear of this invention or in practicing the method of this invention. The stitchdown shoe 10 is characterized by the footwear upper 12 flaring outwardly at its bottom portion to form a horizontal flange 14 about the entire periphery of the upper which is stitched to the midsole 15 or sole 16 of the footwear by stitches 18. The flange 14 of the upper extends inwardly from the outer edge of the sole approximately one quarter of an inch.

Referring now to FIG. 2, there is illustrated the component parts of a typical footwear construction including the upper 12, the midsole 15 and the outer sole 16. The first step in practicing the method of this invention is to prefit the footwear upper.

Before the upper can be joined to the midsole, it is necessary to gather the toe portion of the upper and form a toe pocket. One of the ways that this can be done involves applying a heat-sensitive stiffener 24 to the toe portion of the upper. The upper is then placed in a heat-mold having the desired configuration of the toe portion. The mold applies heat to the stiffener which takes the form of the mold and stiffens after the upper is removed from the mold. This results in the formation of a toe pocket 26 in the upper, as best illustrated in FIG. 4. Various shapes of toe pockets can be formed depending on the particular style of footwear being constructed.

Another method of forming a toe pocket is with the use of a crimping cord (not shown) as described in U.S. Pat. Nos. 2,774,087, 2,946,069 and 2,999,323. As the crimping cord is sewn into the toe portion of the upper, it gathers the upper and forms a toe pocket. This method of forming a toe pocket is described in detail in the patents mentioned above.

Either or both of the above mentioned methods of forming a toe pocket in the upper may be used in the practice of this invention, or any other suitable method of forming a toe pocket in a prefitted upper.

The next step in practicing the method of this invention is to attach the upper to the midsole or sole. In the example described below, the upper is attached to the midsole. The step of attaching the upper to the midsole is essentially a two part process -- the first part involving cementing the upper to the midsole and the second part involving stitching the upper to the midsole.

Thus, pressure-sensitive cement 28 is applied to the flange portion of the upper about the entire periphery of the footwear and is applied to the top side of the midsole about its entire periphery. The cement is applied to both the upper and the midsole in a strip approximately one-quarter of an inch wide. A conventional upper cementer machine can be used to apply cement to the upper and a conventional shoe cementer machine can be used to apply cement to the midsole.

An operator must then manually align the peripheral edge of the bottom portion of the upper with the peripheral edge of the top side of the midsole so that the portion of the upper matches the toe portion of the midsole and the heel portion of the upper matches the heel portion of the midsole. The operator then feeds the mated portions an the midsole to a pair of counter-rotating wheels which apply pressure of approximately 70 pounds to bond the flange of the upper to the top side of the midsole, as illustrated in FIG. 3. At this point in the process described herein, the midsole is attached to the upper.

The machine which bonds the flange of the upper to the top side of the upper has been manufactured by Mutual Machine Company and has been designated a Model C Long Arm/Closing Machine. The machine performs three functions. It applies pressure to the upper and the midsole to bond the cement joint; it continually feeds the work; and it determines the width of the cemented flange of the upper. The last-mentioned function is accomplished by an adjustable stop positioned between the counter-rotating wheels. The stop determines the degree to which the flange of the upper can be inserted between the wheels. In feeding the work through the machine, the operator keeps the midsole in contact with the stop so that the width of upper flange is uniform about the entire shoe.

The next step in the practicing method of this invention is to stitch together the flange portion of the upper and the midsole which have already been cemented together. Because of precementing which precedes the stitching operation, it is not necessary to use a stitch laster machine nor a shoemaker's last to accomplish the stitching operation. The stitches can be sewn on such commonly available stitching machines as a Goodyear Stitcher Machine, a Union Lockstitch Machine, a Littleway Lockstitch machine. It is also possible to use chain stitching machines such as a Puritan Chain Stitcher Machine and a McKay Chain Stitcher Machine when sewing the flange of the upper to the midsole. Referring now to FIG. 4, a single stitch 18 is shown connecting the flange 14 of the upper to the midsole 15. As illustrated in FIG. 1, these stitches extend about the entire periphery of the footwear.

When the upper is cemented and stitched to the midsole, the outer sole is commonly the midsole, to the midsole in a conventional fashion. A final finishing step, which is now necessary in practicing the method of this invention, is to force last the footwear. In this operation a shoemaker's last is forced into the footwear and then removed. The purpose of force lasting is merely to shape the footwear. It should be noted that this force lasting operation is the first time during the production of the stitchdown footwear described herein that a last is used.

Referring now to FIG. 5, the stitchdown shoe described herein may be formed with a ribbed flange 30 rather than the straight flange 15 described above. This is accomplished by prestitching a sheath 32 about the flange portion of the upper prior to the cementing and stitching operations. Since the flange of the upper is approximately one-quarter of an inch wide, the sheath should be approximately one-half an inch wide so that it can be doubled over the flange portion of the upper, as illustrated in FIG. 5. The sheath is then sewn in place using a conventional sewing machine. In the cementing step, cement is applied to the bottom side of the sheath rather than to the bottom side of the flange portion of the upper. The bottom side of the sheath is then bonded to the midsole and stitched, as described above.

Referring now to FIG. 6, a third embodiment of footwear constructed according to the method of this invention is illustrated. In this embodiment, the flange portion 14 of the upper is cemented and stitched directly to the sole 16 in the same manner described above with respect to the midsole 15.

Referring now to FIG. 7, a fourth embodiment of footwear constructed according to the method of this invention is illustrated. In this embodiment, as in the second embodiment illustrated in FIG. 5, a sheath 32 is prestitched about the flange 14 of the upper so as to form a rib 30. However here, the sheathed flange portion of the upper is attached directly to the sole 16 in the same manner described above with respect to the midsole 15.

Referring now to FIG. 8, a fifth embodiment of footwear constructed according to the method of this invention is illustrated. In this embodiment, before or after the flange portion of the upper is cemented to the midsole, as described with respect to the first embodiment, the outer sole 16 is cemented to the midsole 15. In the stitching operation, the flange of the upper is sewn to the outer sole through the midsole in the same manner described above with respect to the first embodiment.

Referring now to FIG. 9, a sixth embodiment of footwear constructed according to the method of this invention is illustrated. In this embodiment before or after the sheathed flange portion of the upper is cemented to the midsole, the outer sole is cemented to the midsole. In the stitching operation the sheathed flange of the upper is sewn to the outer sole through the midsole in the same manner described above with respect to the first embodiment.

While the principles of the invention have now been made clear in the illustrated embodiments, it will be immediately obvious to those skilled in the art that many modifications may be made in the structure, arrangement and proportions of the elements, materials, and components used in the practice of the invention, without departing from the invention. The appended claims are, therefore, intended to cover and embrace any such modifications, within the limits only of the true spirit and scope of the invention.

With respect to FIGS. 5, 7 and 9, an alternative to the sheathing operation described is to fold and stitch the outermost portion of the outwardly turned bottom portion of the upper beneath itself on a sewing machine with a commonly used folding attachment. This then creates the same rounded, finished edge as accomplished by sheathing or binding.

Claims

What is claimed is:

1. A method of manufacturing non-lasted stitchdown footwear comprising the steps of:

prefitting a footwear upper to the sole or midsole of the footwear so that the end edge of a portion of the outermost periphery of the upper which is flattened against the sole or midsole is coextensive with the sole or midsole including the steps of precutting the footwear upper so that the end of a portion of the outermost periphery of the upper which is flattened against the sole or midsole is coextensive with the sole or midsole and forming a toe pocket in the footwear upper;

bonding the flattened peripheral portion of the footwear upper to the sole or midsole including the steps of applying a bonding agent to the underside of the upper flattened portion and to the top side of the sole or midsole outermost peripheral portion, matching together the flattened or flange portion of the upper and the midsole or sole outermost peripheral portion and applying pressure to the matched together portions; and

stitching the flattened peripheral portion of the footwear upper to the sole or midsole with a stitching machine.

2. The method recited in claim 1, further comprising, before the step of prefitting the footwear upper to the sole or midsole, the step of stitching a sheath about the outermost periphery of the footwear upper.

3. The method recited in claim 2, the step of bonding the flattened portion of the upper to the sole or midsole comprising the steps of:

applying a bonding agent to the underside of the sheathed upper flattened portion and to the top side of the sole or midsole outermost peripheral portion;

matching together the sheathed flattened or flange portion of the upper and the midsole or sole outermost peripheral portion and applying pressure to the matched together portions.

4. The method recited in claim 1, the pressure applied to the matched together portions being approximately 70 pounds.