GB2284534A

GB2284534A - Method of and component for footwear manufacture

Info

Publication number: GB2284534A
Application number: GB9424169A
Authority: GB
Inventors: Malcolm Owen; Derrick Michael Laundon
Original assignee: CHAMBERLAIN COMPONENTS Ltd
Current assignee: CHAMBERLAIN COMPONENTS Ltd
Priority date: 1993-12-01
Filing date: 1994-11-30
Publication date: 1995-06-14
Anticipated expiration: 2014-11-30
Also published as: GB2284534B; GB9424169D0

Abstract

A component for use in the construction of an item of footwear comprises an insole (1) and a shank (8). The insole (1) has an upper side that, in use, faces the foot of the wearer and a lower side that, in use, faces the ground. The shank (8) is attached to the lower side of the insole and has a rear end portion (10) that is in direct mechanical engagement with the insole (1). As shown the end of shank (8) has a stepped portion which extends through an aperture in the insole and engages the upper surface of the insole. In Fig. 6, not shown, the end of the shank has a U-shaped portion which engages in a recess in the rear end of the insole. In Fig. 11, not shown, the shank has prongs thereon which engage in the rear wall of a recess in which the shank lies. <IMAGE>

Description

METHOD OF AND COMPONENT FOR FOOTWEAR MANUFACTURE This invention relates to a method of, and a component for use in, the manufacture of footwear. More particularly, although not exclusively, the invention relates to insoles for ladies' shoes and the manufacture thereof.

The insole is an extremely important component of a shoe. It is the first component to be placed on the last and it is the part to which all the other components, such as the heel, the sole and the upper, are attached (whether directly or indirectly).

Generally, an insole for a ladies' shoe with a high or medium high heel comprises a relatively flexible fore part to allow flexibility of the shoe in the region of the toes and the ball of the foot and a much stiffer rear part, which extends through the instep and the heel regions of the foot. This rear portion forms a bridge between the ball of the foot and the heel, and its rigidity is important as it provides support for the foot and a solid platform for the attachment of the heel.

The rigidity of the rear portion of the insole is often increased by the provision of an additional stiffening means in the form of a tempered steel shank. The shank is generally affixed to the underside of the rear portion by rivets. The shank provides reinforcement to the waist of the shoe and encourages the shoe to bend in the correct region when being worn.

A problem with ladies' shoes of this type is that they sometimes make an audible clicking noise when the wearer is walking. This is annoying to the wearer and it is one of the commonest reasons for shoes being returned to the retailer and/or the manufacturer. This leads to a loss of profits and, possibly, a loss of goodwill and reputation.

The applicants have discovered that this clicking noise can be caused when the rivet securing the shank to the heel of the insole becomes loose, allowing relative movement between those parts. During walking, the leverage on the shank caused by bending of the foot can then cause the shank to slip relative to the rivet, producing the clicking noise.

A further problem with the known method of attaching the shank to the insole is that it is complicated and timeconsuming, leading to high manufacturing costs.

It is an object of the present invention to mitigate at least some of the problems mentioned above.

According to the invention there is provided a component for use in the construction of an item of footwear, the component comprising an insole having an upper side that, in use, faces the foot of the wearer and a lower side that, in use, faces the ground, and a shank attached to the lower side of the insole, the shank having a rear end portion that is in direct mechanical engagement with the insole.

Because the rear end of the shank engages the insole directly, the need for separate fixing means is avoided.

The number of components required to manufacture the footwear is thus reduced and the manufacturing process is made simpler. Further, as there is no metal-to-metal contact, the source of annoying clicking noises is removed.

Advantageously, the rear end portion of the shank directly engages the upper side of the insole.

Advantageously, the insole includes an aperture and the rear end portion of the shank extends through said aperture. The rear end portion of the shank may be stepped. The upper side of the insole may include a recess that accommodates the rear end portion of the shank. Preferably, the recess is in communication with, and extends rearwards of, the aperture.

Advantageously, the rear end portion of the shank extends around the rear edge of the insole. The insole may include a cut out portion in its rear edge, to accommodate the rear end portion of the shank. The insole may include a recess in its upper side to accommodate the rear end portion of the shank. The recess may be in communication with, and extend forwards from, said cut out portion.

Advantageously, the rear end portion of the shank has a sharpened formation that is pressed into the insole.

The sharpened formation is preferably pressed into a substantially vertical wall formed in the lower side of the insole.

The curvature of the shank may be greater than the curvature of the insole.

Advantageously, the shank includes a front end portion, said front end portion being attached to said insole by a fixing means.

The present invention further provides an item of footwear including a component as described in any one of the preceding claims.

According to the present invention there is further provided a method of manufacturing a component for use in the construction of an item of footwear, the component comprising an insole having an upper side that, in use, faces the foot of the wearer and a lower side that, in use, faces the ground and a shank, the method comprising bringing the rear end portion of the shank into direct mechanical engagement with the insole, urging the remaining portion of the shank into engagement with the lower side of the insole and securing the front end portion of the shank to the insole.

Noteworthy features of the embodiments described below include the following novel features. First, as only one end of the shaft is secured by means of a rivet, fewer rivets are required to secure the shaft to the insole, which provides a cost saving. Secondly, as a rivet is not used to secure the shank in the heel area, there is no metal-to-metal contact and so no source of noise, even if the shank should work slightly loose.

In an embodiment of the invention, an insole of the type known as "blended" is provided with an aperture in the form of a slot located in the rear portion of the insole in the region of the heel. One end of the shank passes through the aperture from the sole-facing side of the rear part of the insole to emerge on the foot-facing side of the rear part of the insole. The region of the shank upstanding from the foot-facing side of the sole is bent over to lie flat on the insole. A recess may be provided in the foot-facing side of the insole to receive the bent over portion of the shank, to ensure that it does not project above the surface of the footfacing side of the insole. The remainder of the shank, which is generally curved, extends longitudinally and the shank abuts the sole-facing side of the rear portion and is secured thereto by means of a rivet or the like.

In a further embodiment of the invention, the shank is formed with longitudinally extending projections such as prongs or fingers at one end. The prongs of said shaft are caused to penetrate the sole-facing side of the rear part of the insole and extend lengthwise into the material forming the insole and are retained therein.

The remainder of the shank, which is generally curved, extends longitudinally with the shank abutting the solefacing side of the rear part of the insole.

According to the invention there is also provided a shank for use in manufacturing/constructing insoles, one end of said shank being formed so as to be received in and passed through an aperture formed in the rear part of said insole.

According to the invention there is further provided a shank for use in constructing/manufacturing insoles, one end of said shank being formed with longitudinally extending projections such as prongs.

According to the invention there is also provided a method of manufacturing an insole, the method comprising the step of securing a rigid shank to the rear part of the insole. One end of said shank may be secured to the foot-facing side of the rear part and the other end may be secured to the sole-facing side of the rear part.

According to the invention there is further provided a method of constructing/manufacturing an insole, said method comprising the step of securing a rigid shank to an insole, one end of said shank having longitudinally extending prongs that penetrate the surface of the insole and are retained within the material forming said insole, the other end being retained on the surface of the sole-facing side by means of a rivet.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, of which: Figure 1 is a side view, in cross section, of a prepared insole without a shank; Figure 2 is a side view of a shank, and Figure 3 is a side view, in section, of a finished insole with the shank attached.

Figure 4 is a perspective view of the finished insole from above, Figure 5 is a bottom view of the finished insole, Figure 6 is a simplified perspective view of a shank according to a second form of the invention, Figure 7 is a bottom view of the second form of the shank, Figure 8 is a perspective view of an insole according to a second form of the invention, Figure 9 is bottom view of a shank, according to a third form of the invention, Figure 10 is a side view, in cross-section, of a finished insole according to a third form of the invention, and Figure 11 is a bottom view of an insole according to the third form of the invention.

Figures 1 to 5 of the drawings show an insole 1 for a ladies' shoe having a medium-high or high heel. The insole has a front portion 2 made of relatively thin, flexible material such as leatherboard and a thicker, stiffer rear portion 3, which may be made of fibreboard.

At the joint 4 between the front and rear portions, the edges of the front and rear portions overlap and are feathered and bonded to one another. The front portion 2 extends under the toes and the ball of the wearer's foot and the rear portion 3 extends under the arch and the heel of the foot. The rear portion 3 is curved to form a bridge between the front portion 2 and the heel of the shoe.

The shank 8 comprises a strip of tempered steel. The shank has front and rear end portions 9,10 and a middle portion 11, which has a U-shaped cross-section forming a rib 12, which increases its stiffness. The front end portion 9 is substantially flat and is provided with a hole 13 for a fixing such as a rivet. The rear end portion 10 has a stepped formation, including an upwardly-bent riser 14 and a rearwardly-extending tongue 14a.

The shank 8 is curved slightly from end to end, its natural curvature being slightly greater than the curvature of the rear portion 3 of the insole. This ensures that the shank is deformed slightly when it is attached to the insole, so placing the shank and the rear portion of the insole in tension and causing the middle portion 11 of the shank to be pressed firmly against the underside of the insole.

A groove 15 of rectangular cross-section is provided in the underside of the insole to accommodate the shank 8.

The length and width of the groove are substantially matched to those dimensions of the shank and its depth is approximately equal to the thickness of the metal strip from which the shank is formed so that, when the shank 8 is attached, its edges lie flush with the lower surface of the insole. The rib 12 formed by the Ushaped cross-section stands slightly proud of the lower surface of the insole.

At the rear end of the groove 15 a slot 21 is formed which extends through the thickness of the insole. A recess 22 is provided in the upper surface of the insole, which extends rearwards from the slot 21. The shape and depth of the recess 22 are matched to the dimensions of the tongue 14a at the rear end of the shank 8. A hole 24 for a fixing rivet extends through the insole near the forward end of the groove 15.

To attach the shank to the insole, the tongue 14a of the stepped rear end portion is first inserted through the slot 21 in the heel portion of the insole. The shank 8 is then pivoted around the fulcrum formed by the engagement of the stepped portion 14 with the slot 21, until the middle portion 8 lies in the groove 15 in the underside of the insole. This causes the tongue 14a to lie flat in the recess 22, so that its upper surface is flush with the upper surface of the insole.

Finally, the forward end of the shank is then pressed against the insole, placing the shank in tension and urging the tongue 14a firmly into the recess 22. The forward end of the shank 8 is secured to the insole by a rivet 25 that extends through the aligned holes 13,20 of the shank and the insole.

By this arrangement, the rear end of the shank 8 is firmly secured to the insole without a separate fixing means and with no metal-to-metal contact. Because the rearward end of the shank is pressed against the upper surface of the insole by the tension in the shank, small movements between those parts can be accommodated without affecting the security of the mounting.

Further, because there is no metal-to-metal contact, slight movements between the insole and the shank do not cause audible clicking or squeaking noises.

In the embodiment of the invention shown in Figs. 6-8, the rear portion 10 of the shank 8 has a hooked shape and consists of a substantially vertical portion 30 and a retroflex portion 30a. The hook portion passes around the rear edge of the insole so that the retroflex portion 30a engages the upper surface of the insole.

Recesses 32,33 are provided in the rear edge and the upper surface of the insole, to accommodate the vertical portion 30 and the retroflex portion 30a of the shank.

The method of attaching this form of the shank is very similar to that described above, except that instead of passing the rear end portion through a slot in the insole, it is hooked over the rear edge of the insole.

This form of the invention provides the advantage that the shank extends to the very rear edge of the insole, which to increase the rigidity of the rear portion of the insole and provides a particularly firm base to which the heel may be attached.

In a third form of the invention shown in Figs. 9-11, the rear end of the shank is substantially flat and is provided with two sharp prongs 35. The groove in the under side of the insole ends abruptly at its rear end with a vertical wall 36, into which the prongs 35 can be forced. The shank is thus attached to the insole by first forcing the prongs firmly into the rear wall of the groove and then securing the front end of the shank to the insole with a rivet. As in the two embodiments described above, the rear end of the shank is connected directly to the insole, thereby avoiding the need for a separate fixing and any metal-to-metal contact.

Claims

Claims:

1. A component for use in the construction of an item of footwear, the component comprising an insole having an upper side that, in use, faces the foot of the wearer and a lower side that, in use, faces the ground and a shank attached to the lower side of the insole, the shank having a rear end portion that is in direct mechanical engagement with the insole.

2. A component for use in the construction of an item of footwear, the component comprising an insole and a shank.

3. A component according to claim 1 or claim2, in which the rear end portion of the shank directly engages the upper side of the insole.

4. A component according to claim 3, in which the insole includes an aperture and the rear end portion of the shank extends through said aperture.

5. A component according to claim 4, in which the rear end portion of the shank is stepped.

6. A component according to claim 4 or claim 5, in which the upper side of the insole includes a recess that accommodates the rear end portion of the shank.

7. A component according to claim 6, in which the recess is in communication with, and extends rearwards of, the aperture.

8. A component according to claim 3, in which the rear end portion of the shank extends around the rear edge of the insole.

9. A component according to claim 8, in which the insole includes a cut out portion in its rear edge, to accommodate the rear end portion of the shank.

10. A component according to claim 8 or claim 9, in which the insole includes a recess in its upper side to accommodate the rear end portion of the shank.

11. A component according to claim 10 when dependent on claim 9, in which the recess is in communication with, and extends forwards from, said cut out portion.

12. A component according to claim 1 or claim2, in which the rear end portion of the shank has a sharpened formation that is pressed into the insole.

13. A component according to claim 12, in which the sharpened formation is pressed into a substantially vertical wall formed in the lower side of the insole.

14. A component according to any one of the preceding claims, in which the curvature of the shank is greater than the curvature of the insole.

15. A component according to any one of the preceding claims, in which the shank includes a front end portion, said front end portion being attached to said insole by a fixing means.

16. An item of footwear including a component as claimed in any one of the preceding claims.

17. A method of manufacturing a component for use in the construction of an item of footwear, the component comprising an insole having an upper side that, in use, faces the foot of the wearer and a lower side that, in use, faces the ground and a shank, the method comprising bringing the rear end portion of the shank into direct mechanical engagement with the insole, urging the remaining portion of the shank into engagement with the lower side of the insole and securing the front end portion of the shank to the insole.

18. A component for use in the manufacture of footwear, the component being substantially as described herein with reference to, and as illustrated by, Figs. 1 to 5, or 6 to 8 or 9 to 11 of the accompanying drawings.

19. A method of manufacturing footwear, the method being substantially as described herein with reference to, and as illustrated by, Figs. 1 to 5, or 6 to 8 or 9 to 11 of the accompanying drawings.