CA2179108C - A shoe having an air-cooled breathable shoe liner - Google Patents

Abstract

A conventional shoe which comprises a shoe upper of continuous and uninterrupted material attached to an outer sole has its shoe upper lined with an air-cooled, breathable shoe liner comprising an outer knit layer of hydrophilic material, an inner knit layer of hydrophobic material, and monofilament yarns of hydrophobic material extending between and interknitted with the outer and inner layers for maintaining an air chamber therebetween, such that moisture from the foot of the wearer is transmitted by the inner layer and the monofilament yarns through the air chamber and is absorbed by the outer layer and passes into the shoe upper to be dried by the outer air.

Description

` 217910~

This invention relates generally to a shoe having a conventional closed shoe upper attached to a conventional outer sole of a dress, casual or sport shoe, or boot. More particularly, an air-cooled breathable shoe liner is provided according to the invention which lines at least the shoe upper for aerating the foot of the wearer to m~in~in the foot substantially p~l~pil~lion free.
Multi-layered liners for shoe uppers have been provided as having an intermediate layer of synthetic foam material, such as polyurethane foam, which acts as a cushioning agent. However, the polyurethane foam is not only not breathable but acts as an in~ or, co~ g foot ~l~pil~lion and heat, which brings about foot discomfort and foot fatigue.
Shoe structures for aerating the foot are known to provide a window opening in the shoe upper covered by a conventional mesh for aerating the foot.
However, such shoe structure is costly to produce as a seasonal shoe satisfactory only when worn during warm and dry weather conditions.
A shoe construction restricted to use as a shoe upper for especially an athletic shoe, is disclosed in U.S. Patent 4,785,558 as allegedly exhibiting airpermeability and suitable elasticity.
As described, the shoe upper according to this prior patent comprises a three-dimensional structure of outer and inner knit fabric layers, the outer layer preferably being a filament yarn or a spun yarn made of a synthetic fiber havingexcellent wear resistance, while the inner knit fabric layer is preferably a spun yarn made of a natural fiber having moisture absorbtivity, i.e., hydrophilic. The inner and outer layers are spaced apart and are interknitted by a crossing thread, preferably of a synthetic monofilament or multifilament, using a known Raschel knitting machine.
The shoe upper of such a three-dimensional structure functions unlike that of a shoe Iiner in that the moisture abs~ g inner layer in contact with the foot of the wearer retains moisture due to foot ~l~pir~lion which inle,rel~s with the ability of the shoe upper to air cool the foot. This known shoe upper is mainly structured as a soft, three~limen~ional structure for enh~ in~ the effect of alleviating a sense of o~ples~ion and a sense of ~atigue when used as a shoe upper of an athletic shoe.
It is therefore an ob~ect of the present invention to provide a shoe lining which lines the shoe upper of a closed shoe, which may be of the dress, casual, boot or s-port type~ for providing an air chamber surrounding the foot which ~0 facilitates air circulation keeping the foot dry, avoiding foot fatigue and enhancing foot comfort. The shoe liner is a knit fabric which may be manufactured in a Raschel loom or a warp fiame loom of known type. The liner eJ..,.i~es foam as both a cushioning agent and an insul~tor~ and which instead utilizes an air chamber bel~e~ l the inner and outer spaced knit layers to facilitate air cooling the foot. The air chamber is ~-~?~ f~d by monofil~ment yarns i.~ ;,k,~ ed with the inner and outer layers.
The inner layer of the shoe liner according to the invention comprises a knit layer of hydrophobic material such as a polyester, and the outer layer co~ ,ises a knit layer of hydrophilic material such as nylon. The monofilS~n~en$yarns are of hydrophobic material such as polyester. With such a liner col~sl- tl ilion, neitner the inner layer ~against the foot) nor $he monofilament yarns~
being of hydrophobic fibers, absorbs foot p~ls~udlion but pass the moisture vapor and heat tbrough the air chamber to the outer layer of L~ 3hilic nylon which absorbs all ~is moisture and passes it through to the shoe upper which e~a~les in the ~trnosphPre.
Thus, the entire liner is breathable for aerating the foot clad in a standard shoe having a cG"~ aional, closed shoe upper. Further, moisture is not absorbed 2179108 :

at the inner layer, but is transported away from the foot to the shoe upper for evaporation. The monofilaments are inlel~lilled to both the knitted inner and outer layers for cushioning the foot, which adds softness and comfort for the wearer as well as structured integrity to the composite lining material.
The knitted fabric liner according to the invention may likewise be utilized as an inner sole for lining the outer sole of the shoe which even further adds to the comfort, softness and cushioning realu~es of the shoe.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the invention when taken in conJunction with the accompanying drawings wherein:
Figure 1 is a side elevational view of a conventional shoe, partly broken away to illustrate the shoe lining according to the invention;
Figure 2 is a sectional view taken substantially along the line 2-2 of Fig. l;
Figure 3 is a broken plan view at an enlarged scale, of the shoe lining construction according to the invention; and Figure 4 is a sectional view taken substantially along the line 4-4 of Fig. 3.
Turning now to the drawings wherein like reference characters refer to like and corresponding parts throughout the several views, a conventional, completelyclosed shoe 10 is shown in Fig. 1 incorporating the shoe lining according to theinvention, the shoe being illustrated as a dress shoe, although the present shoelining is likewise adaptable for use with casual and sport shoes and boots, as well.
Shoe upper 11 of the shoe may be of genuine or imitation leather material or the like which completely encloses the foot, i.e., the shoe upper does not have window openings nor is comprised of straps or the like, but is rather continuousand u~ ellul)t~d, except, of course, for eyelets 12. The shoe upper is attached to outer sole 13 in any normal manner.
Shoe lining 14 according to the invention completely lines the entirety of shoe upper 1 1 and is attached thereto as by spot stitching 15 (Figs. 1, 2~ or the like.
The shoe liner, structured as best shown in Figs. 3 and 4, includes an outer knit layer 16 in intim~te contact with the inner surface of the entirety of shoe upper I 1.
The outer knit layer is formed of a hydrophilic material such as nylon having a S yarn fineness of about 90 denier. The term "hydrophilic" is to be understood as a property of the material, such as moisture absorbing nylon, having a strong aff1nity for moisture.
Shoe lining 14 further comprises a inner knit layer 17 which may be textured as shown in Fig. 3 or which may otherwise be plain without departing from the invention. The inner knit layer is of hydrophobic material such as polyester which may have a yarn fineness of about 40-150 denier. The term "hydrophobic" is intended to identify the propelty of the inner knit layer as lacking affinity for moisture.
The inner knit layer is spaced from the outer layer a predetermined distance to form an air chamber 18 between the layers. The inner and outer layers are m~int~ined in their spaced apart relationship by the provision of monofilament yarns 19 which are interknitted with both the inner and outer knit layers in a known manner such as with the use of the well-known Raschel tricot knitting machine. The monofilament yarns are of a hydrophobic material such as a polyester having a yarn fineness of about 30 denier and extend between the innerand outer knit layers in a substantially perpendicular fashion thereto as exaggerated in Fig. 4.
The inner knit layer, in contact with the wearer's foot, being moisture hating, and the monofilament yarns intermediate the layers, likewise being moisture hating, do not absorb foot pe~ tion but pass the moisture vapor and heat through the air chamber to the outer layer of moisture loving material which absorbs all this moisture and passes it through to the shoe upper 11 to evaporate in

2 1 79 1 08 the ~wlounding atmosphere. The air enters at outer edge 21 o~ the shoe and circulates through the air chamber about the foot at least inside the shoe upper.
The moisture absorbed from the foot by the hydrophobic yarns is l~ illed into the shoe up~er via outer knit layer 16 to be dried by the outside air. The foot is thus dried and air cooled by the liner which likewise renders the shoe soft, colllf~ ble and cushiony.
Shoe liner 14 according to the invention can likewise be applied as an insole 22 overlying outer sole 13 such that the entirety of the foot is ef-c~ps~ ted by air chamber 18. The movements of monofilaments 18 are entirely flexible and crushable when the shoe liner is uti~ized as an insole, such that air chamber 18 will be ~ ed by the tiny monofil~ment~ 19 ~ in~ and i~ k~ d to the inner and outer knit yarns o~the insole.
The shoe lini~g construction of the knitted fabric according to invention eli~ tes foam as a cushioning agent, and the layers forming the lining are neither 1~l~.in~led together nor is adhesive required for interconnectin~ the layers.
The shoe upper is lined with the knit fabric according to the invention in any suitable manner know~ in the shoe construction art, and functions as an air cooled breathable liner which reduces ~oot fatigue caused by foot ~rs~ildlion, and provides a cushiony, co~ lable and soft wear.
ZO Obviously, many modifications and va}iations of the present invention are made ~ossible in the light of the above teachings. For example, elastic or Lycrayarns could be knitted into the liner to produce an integ~l stretch feature for added foot comfort eli...i~ the need for shoe laces, buckles, etc. It is llæl~ol~ to be understood that within the scope ~ the appended claims the invention may be practiced otherwise than as specifically described.

Claims (6)

The embodiments of an invention in which an exclusive property or privilege is claimed are defined as follows:

1. A shoe comprising, an outer sole, a shoe upper of continuous and uninterrupted material attached to said outer sole and an air-cooled breathableshoe liner for lining at least said shoe upper, the liner comprising an outer knit layer of hydrophilic material in engagement with at least an inner surface of said shoe upper, an inner knit layer of hydrophobic material spaced from said outer layer to define an air chamber, said inner layer being adapted to engage a foot of the wearer, and a plurality of monofilament yarns of hydrophobic material extending between and interknitted with said outer and inner layers for maintaining the air chamber, whereby moisture from the foot of the wearer is transmitted by the inner layer and the monofilament yarns through the air chamber and is absorbed by the outer layer and transmitted into said upper to be dried by the outer air.

2. The shoe according to claim 1, wherein said outer layer comprises knitted yarns of moisture absorbing nylon.

3. The shoe according to claim 1, wherein said inner layer comprises knitted yarns of polyester.

4. The shoe according to claim 1, wherein said monofilament yarns are polyester.

5. The shoe according to claim 1, wherein said inner layer is textured.

6. The shoe according to claim 1, wherein said liner further comprises an inner sole lining said outer sole.