EP0437969A2

EP0437969A2 - Footwear

Info

Publication number: EP0437969A2
Application number: EP90314124A
Authority: EP
Inventors: Frederick Wilkin Chinnock
Original assignee: C&J Clark International Ltd
Current assignee: C&J Clark International Ltd
Priority date: 1990-01-19
Filing date: 1990-12-21
Publication date: 1991-07-24
Also published as: EP0437969A3; IE910168A1; GB9001287D0

Abstract

In making a boot or shoe of the veldtschoen type, the upper (10) is lasted to a runner (14) and has its bottom edge turned outward to form a flange (12) which is stitched to the runner, the part of the runner outward of the stitching being cut away. A sole unit (18) is moulded directly on to the runner and the underside of an edge portion of the flange (12) projecting beyond the runner.

Description

This invention relates to footwear and is more particularly concerned with the manufacture of boots and shoes of veldtschoen construction.
In one commonly used construction, the out- turned flange of the upper is stitched and glued to a runner, and a sole unit is then directly moulded on to the underside of the runner, edge portions of the runner and flange projecting laterally beyond the sole unit being then trimmed off. A proportion of shoes and boots employing this construction fail by separation of the sole unit and runner in wear, and the present invention is concerned with alleviation of this problem.
According to this invention there is provided an article of footwear comprising an upper lasted to a runner and having its bottom edge portion turned outwardly to form a flange which is stitched to the runner, and a sole unit moulded by direct moulding on to the runner and on to the underside of an edge portion of said flange which projects laterally beyond the runner.
The invention also provides a method of making an article of footwear comprising the steps of shaping an upper about a last, turning the edge of the upper outward to form a flange, stitching the flange to a runner, cutting away the peripheral portions of the runner so that the edge of the runner is outward of but closely adjacent the stitching, moulding a sole unit directly on to the runner and the underside of a peripherally-extending margin of the flange projecting beyond the edge of the runner. Any part of the flange projecting laterally beyond the sole unit is then trimmed off.
Preferably the stitching is constituted by a single line of stitching which is angled so that the area encompassed by the stitching is greater on the upper side of the flange than on the underside of the runner. If desired the cutting of said peripheral portions of the runner may be correspondingly angled.
The runner is preferably made from a high strength bonded fibre to provide maximum stitch holding strength.
One embodiment of the invention will now be described by way of example with reference to the accompanying diagrammatic drawings in which:

Figures 1 to 5 illustrate, in section at right angles to the lengthwise dimension of a shoe, a sequence of five principal steps in the manufacture of a shoe according to the invention.

Referring first to Figure 1, the upper 10 of the shoe is shaped about a last 11 and its edge is turned outward to form a flange 12 which is then secured by an adhesive and a line of stitching 13 to a runner 14 underlying the last. The stitching 13 is inclined inwardly so that it encompasses a smaller area on the underside of the runner 14 than on the upper side of the flange 12. The adhesive is preferably only sufficiently strong to withstand the strains of manufacture and is applied to the upper surface of the runner and to the underside of the flange 12. A routing and scouring operation is then carried out on the runner as shown in Figure 2 to cut away the peripheral portions of the runner leaving a margin of not more than about 2mm outward of the line of stitching 13, as shown in Figure 3, and to scour the flesh-side or underside of the flange mechanically to cut away the surface layer carrying the adhesive, and to provide the flange with a surface which will form a powerful bond with polyurethane. The cut may be angled similarly to the stitching.
The assembly is then placed over a cavity mould 16 which defines the external shape of the sole unit 18 as shown in Figure 4. The flange 12 is dimensioned to project beyond the edge of the cavity and its projecting margin is clamped to the top surface of the cavity mould 16 about the cavity by an upper part 19, and the assembly is held rigidly by the part 19 while polyurethane is injected into the mould cavity. The cut edge of the runner is spaced away from the side wall of the cavity so that the polyurethane engages and adheres strongly to the underside of the runner and to a margin of the underside of the flange 12 about the runner.
When curing of the polyurethane sole unit 16 is completed the shoe and last are separated from the mould and the part 12a of the flange projecting beyond the edge of the sole unit as shown in Figure 5 is trimmed off.
The runner is preferably of high strength bonded fibre material to provide good stitch holding properties.
In the resulting shoe, the outer portions of flange 12 adhere directly strongly to the sole unit and the high strength of this adhesion has been found to reduce to a marked degree the risk of separation of the runner and sole unit in wear, and to remove the formerly critical nature of the bond of adhesion between the flange and the runner in reinforcing the effect of the stitching. The angled stitching and the inclined cutting of the edge of the runner serves to maximise the area of bonding between the flange 12 and the polyurethane of the sole unit for a given width of the flange.

Claims

1. An article of footwear comprising an upper lasted to a runner and having its bottom edge portion turned outwardly to form a flange which is stitched to the runner, and a sole unit moulded by direct moulding on to the runner and on to the underside of an edge portion of said flange which projects laterally beyond the runner.

2. An article of footwear as claimed in claim 1, wherein the stitching is constituted by a single line of stitching which is angled so that the area encompassed by the stitching is greater on the upper side of the flange than on the underside of the runner.

3. A method of making an article of footwear comprising the steps of shaping an upper about a last, turning the edge of the upper outward to form a flange, stitching the flange to a runner, cutting away the peripheral portions of the runner so that the edge of the runner is outward of but closely adjacent the stitching, moulding a sole unit directly on to the runner and the underside of a peripherally-extending margin of the flange projecting beyond the edge of the runner.

4. A method as claimed in claim 3, comprising the step of angling the line of stitching so that the area encompassed the stitching is greater on the upper side of the flange than on the underside of the runner.

5. A method as claimed in claim 4, wherein the cutting away of said peripheral portions of the runner is correspondingly angled.