EP1042967A1

EP1042967A1 - Footwear

Info

Publication number: EP1042967A1
Application number: EP00301596A
Authority: EP
Inventors: Michael H. Ganon
Original assignee: Totes Isotoner Corp
Current assignee: Totes Isotoner Corp
Priority date: 1999-04-09
Filing date: 2000-02-29
Publication date: 2000-10-11

Abstract

A slipper (10) with a durable outsole (20), and a separable resilient insert (38) placed on top of the outsole. The slipper preferably includes an insole (62) covering the separate resilient insert, and a vamp (12) attached to the outsole. When in use, the durable outsole is resistant to wear and abrasion, and the separate resilient insert provides comfort to the user's foot because the resilient insert is separate from and movable relative to the outsole when a user walks in the slipper.

Description

This invention relates to footwear. More specifically, this invention relates to footwear having an outsole and a resilient insert.
Footwear known in the prior art often compromises foot comfort in order to create a more durable product, or sacrifices product durability in order to create a more comfortable product. For example, a boot intended for rigorous hiking and mountaineering must have a durable and rigid sole to provide traction and also to prevent injury to a user's foot from stepping on irregular surfaces. On the other hand, a slipper dedicated to indoor use may sacrifice all but a minor amount of protection to the sole of the user's foot in order to maximize the comfort desired. In all, factors such as weight, aesthetic design and support are taken into account when designing footwear, and the final design of the footwear product is primarily dependent on the intended use of the product.
Slipper manufacture, in particular, is generally focused on the comfort of the footwear. Slippers are generally worn inside the house, and are not often subjected to the abuses of outside-wear where a user treads on hard and abrasive surfaces such as blacktop and concrete, and irregular and potentially injurious surfaces such as sticks, rocks, broken glass, or the like. Slippers designed for comfort rather than durability would quickly wear out if subjected to hard use outside the home.
With slippers that attempt to provide a durable outsole for outside wear, the basic problem is that while they incorporate a relatively durable outsole with a tread pattern for traction, the slippers, by virtue of their hard outsole, sacrifice that quantum of comfort desired in slippers designed to be worn primarily inside. Slippers with relatively hard outsoles often have only a foam and/or cloth insole to absorb the shock created by a user's foot falls, and this insole is adhered to the inner surface of the hard outsole. The cloth insole does not offer any effective resilience for the user's foot. And the foam insole often loses its resilient properties after prolonged use, and often does not even offer much comfort to a user when puchased new. Also, and because such insoles deform easily, a user's foot can press forward into the toe of the slipper, not only further deforming and eventually tearing the insole, but also prematurely wearing out the slipper toe by wearing a hole in it.
Accordingly, it has been one objective of this invention to provide footwear that has the benefits of a durable outsole that can be worn outside while simultaneously providing a level of comfort normally associated with softer and less durable footwear such as a slipper that is worn inside.
It has been another objective of the present invention to provide footwear that is not only durable and comfortable to wear, but that also is resistant to material fatigue and ultimate failure normally associated with prior art slipper type footwear.
In accord with these objectives, this invention provides in a preferred embodiment footwear, e.g., a slipper, that will overcome the above-mentioned disadvantages by pairing a durable outsole with a separate resilient insert to create a footwear product that is both durable and comfortable. When in the preferred slipper form, the footwear includes a vamp attached to the durable outsole around the outer margin thereof, the outsole having a sole bed and a peripheral rim integral therewith. The separate resilient insert is seated on the inside surface of the outsole, and is confined laterally in assembly therewith by the outsole's peripheral rim. The separable resilient insert is relatively softer than the durable outsole, and has a bottom surface in which a matrix of recesses is defined. The recess matrix reduces the weight of the insert to make the slipper lighter, and also adds to the slipper's comfortable feel by enhancing the slipper sole's resilience when worn by a user. The separable resilient insert variably compresses in proportion to the user's weight and walking forces applied upon the insert when the slipper is worn, thereby giving the feel of a custom fit to the user. The peripheral margin of the resilient insert is similar in shape to, but slightly smaller than, the peripheral margin of the outsole in which it is received so that when a user wears the slipper there is permitted relative separation between the outsole and resilient insert, thereby providing the resilient insert with a limited degree of movement inside the outsole as the user walks in the slipper. An insole may be provided on top of the resilient insert to enhance further the user's comfort. Thus the slipper has a durable outsole and a compliant and comfortable resilient insert that is separable from and movable relative to the outsole as the user walks, thereby creating a durable and comfortable slipper for both outdoor and indoor wear.
Other objectives and advantages of the invention will be more apparent from the following detailed description taken in conjunction with the drawings in which;
Fig. 1 is a perspective view of a slipper in accord with the principles of the present invention;
Fig. 2 is a cross-sectional view of the slipper of Fig. 1 taken along lines 2-2;
Fig. 3 is a perspective view of a slipper outsole and cutaway view of a resilient insert for the outsole;
Fig. 4 is a perspective view of an alternative embodiment of a slipper in accord with the principles of the invention;
Fig. 5 is a cross-sectional view of the slipper of Fig. 4 taken along lines 5-5;
Fig. 6 is a bottom view of the resilient insert shown in Fig. 5; and
Fig. 7 is a cross-sectional view of Fig. 5 taken along lines 7-7.
A slipper 10, which may be either of a ballerina style as shown in Fig. 1, or a mule style as shown in Fig. 4, includes a vamp 12 attached to an outsole 20. The vamp 12 defines a foot hole 14 bordered by a collar 16 through which a user may insert a foot in order to wear the slipper 10. As seen in Figs. 3 and 7, the outsole 20 generally is contoured to have a toe 22, heel 24, instep 26, and outer edge 28, so as to generally mimic the contours of a human foot. The outsole 20 further has a sole bed 30 with an inner surface 32 and an outer surface 34. A peripheral rim 36 integral with the sole bed's margin rises above the sole bed inner surface 32. The outsole 20 preferable is made of thermoplastic rubber with a durometer in the range of about 55 to about 70. It will be understood by those in the art that other materials may be used that provide both good traction and durability characteristics suitable for use in footwear.
The slipper 10 has a separable resilient insert 38 seated on or placed against, but not adhered to, the inner surface 32 of the outsole 20, as seen in Figs. 2 and 5. The resilient insert 38 generally has a toe 40, a heel 42, an instep 44, and an outer edge 46 which are similar to, but define a contour slightly smaller than, the contour of the outsole 20, see Fig. 7. This insert 38/outsole 20 structure results in a slight gap G between the insert's periphery 46 and outsole's rim 36 which preferably is of substantially the same width around the insert's periphery. Since the insert 38 is separable from, i.e., not adhered to, the outsole 20, this gap G permits limited relative movement between the insert and the outsole as a user walks in the slipper, thereby enhancing the comfort of this slipper.
The resilient insert 38 has a substantially planar bottom surface 50, and a top surface 48 that is contoured for comfort to generally mimic the contours of the sole of a human foot. As is best seen in Figs. 2 and 5, the resilient insert varies in thickness T from the insert toe 40 to the insert heel 42. The insert 38 preferably has a thickness in the range of between about 60 mm and about 160 mm. The insert 38 is thickest in the regions that will bear the greatest proportion of the user's weight, and therefore also provide areas of the greatest shock absorption when a user walks in the slipper 10 and, as a result, compresses the resilient insert 38. The resilient insert 38 defines a matrix of recesses 54 in the insert bottom surface 50, as seen in Figs. 6 and 7. The combined surface area of all recesses 54 at the insert's bottom surface 50 preferably is between about 50% and about 50% of the entire surface area of the insert's bottom surface. No recess 54 extends through the top surface 48 of the resilient insert 38, thereby leaving a ceiling 56 at the top of each recess 54. The ceiling's thickness C is dependent on the recess height H subtracted from the resilient insert thickness I at any point on a recess ceiling 56. In the preferred embodiment, the ceiling thickness C is in the range of about 1.2 mm to about 2.5 mm.
In the preferred embodiment, the resilient insert 38 is made from a thermoplastic rubber, such as compound TPR-1045S available from J-Von N.A. LLC, 25 Litchfield St., Leominster, MA 01453. The resilient insert 38 is relatively soft compared to the outsole 20, and has a durometer in the range of between about 35 and about 40. The recesses 54 defined in the bottom surface 50 of the resilient insert 38 subtract material from the resilient insert 38, thereby making the resilient insert 38, and therefore the slipper, lighter. The relatively low durometer of the preferred resilient insert 38 allows the insert 38, the recess matrix 54, and the varying thickness T of the insert, to be variably compressed when in use depending on factors such as the user's weight, thereby providing an insert 38 that is resiliently shaped to the contours of a user's foot as the slipper is used which promotes a custom made feel of the slipper 10.
The slipper 10, of both the ballerina style shown in Fig. 1, and the mule style shown in Fig. 4, has an insole 62 and 62a respectively, received against the top surface 48 of the resilient insert 38.
The ballerina style slipper 10 embodiment, as can be seen in Fig. 2, has an insole 62 that is attached (e.g., by stitching) along the bottom margin 18 of the vamp 12. The vamp 12 and insole 62 are then attached (e.g., by stitching) along the top edge margin of the outsole's peripheral rim 36, thus creating a closed pocket 64 in which the separable resilient insert 38 is captured and in which the insert 38 is permitted limited vertical movement when the slipper is worn. In other words, in the ballerina style slipper 10 shown in Fig. 2, et al., the resilient insert 38 is attached to neither the insole 62 nor the outsole 20 and is, therefore, permitted to separate relative to the outsole 20 and the insole 62 when being worn during use.
The mule style slipper 10 embodiment, as can be seen in Figs. 4 and 5, has a resilient insert 38 selectively removable from the outsole 20. The mule style slipper 10 has an insole 62a adhered to the top surface 48 of the resilient insert 38 with any adhesive known to those in the art. Unlike the ballerina style slipper shown in Figs. 1 and 2, the resilient insert 38 in the mule style slipper 10 is not captured in a closed pocket. However, like the ballerina style slipper 10, the bottom surface 50 of the resilient insert 38 is not adhered to the inner surface 32 of the outsole 20 so as to allow relative separation between the resilient insert 38 and the outsole 20 when being worn during use.
In the mule style slipper 10 shown in Figs. 4 and 5, the vamp 12 and the collar 16 are made of a terry cloth-like material. In the ballerina style slipper shown in Figs. 1 and 2, the vamp 12 and the collar 16 are made of a stretchable synthetic textile. It will be understood by those in the art that other materials may be used to provide the desired comfort and wear characteristics for the slipper 10. For example, the insole 62 may be made from a terry cloth and foam composite.

Claims

Footwear comprising

an outsole having a sole bed and an integral peripheral rim extending upwardly therefrom, said sole bed having an inner surface, and

a separable resilient insert having a top surface and a bottom surface, said resilient insert including a matrix of recesses on said bottom surface, said insert bottom surface being in separable contact with said sole bed inner surface, and said insert being confined by said outsole peripheral rim, during use of said footwear.
The footwear of claim 1, wherein said resilient insert has a durometer between about 35 and about 40, wherein said outsole has a durometer between about 55 and about 70, and wherein the collective cross sectional area of said recesses on said insert bottom surface is between about 40% and about 50% of the total bottom surface area of said insert.
The footwear of claim 2, wherein said outsole is made from thermoplastic rubber, and wherein said outsole is made from thermoplastic rubber.
Footwear comprising

an insole,

an outsole having a sole bed and an integral peripheral rim extending upwardly therefrom, and

a separable resilient insert having a top surface affixed to said insole, and a bottom surface in separable contact with said sole bed, said resilient insert and insole combination being not affixed to, and therefor selectively removable from, said outsole.
The footwear of Claim 4, wherein said resilient insert has a durometer between about 35 and about 40, and said outsole has a durometer between about 50 and about 70.
The footwear of claim 4, wherein said insert bottom surface defines a plurality of longitudinally arranged recesses and a plurality of laterally arranged recesses, and wherein the collective cross sectional area of said recesses on said insert bottom surface is between about 40% and about 50% of the total bottom surface area of said insert.
Footwear comprising

an outsole having a sole bed and an integral peripheral rim extending upwardly therefrom,

an insole attached to at least a portion of said peripheral rim to define a cavity between said insole and said sole bed, and

a separable resilient insert having a bottom surface and a top surface, said resilient insert being position in said cavity so that said insert bottom surface is in separable contact with said sole bed.
The footwear of claim 7, wherein said resilient insert has a durometer between about 35 and about 40, and said outsole has a durometer between about 50 and about 70.
The footwear of claim 7, wherein said insert bottom surface defines a plurality of longitudinally arranged recesses and a plurality of laterally arranged recesses, and wherein the collective cross sectional area of said recesses on said insert bottom surface is between about 40% and about 50% of the total bottom surface area of said insert.
A resilient insert for footwear, said insert having a top surface and a bottom surface, said bottom surface defining a matrix of recesses extending upwardly toward said top surface, said insert having a durometer in the range of between about 35 and about 40, and wherein the collective cross sectional area of said recesses on said insert bottom is between about 40% and about 50% of the total bottom surface area of said insert.