The present application relates to footwear and, more specifically, to safety footwear of the type used in construction.
Safety footwear is often required on construction sites. A primary function of safety footwear, such as safety boots or shoes, is to protect the foot against impacts. Accordingly, some items of footwear include a toe-cap (e.g., steel toe or composite toe). The toe-cap defines a volume accommodating the toes of the wearer in the item of footwear so as to protect the toes against the impact from objects falling against the footwear. In most safety footwear, the toe-cap is within the upper and is therefore under the leather or synthetic material forming the exposed surface of the upper. As the material of the upper is above that of the toe-caps, the material of the upper often rips or is damaged over time as a result of abrasion and impact, thereby exposing the toe-cap material. As they are even used as “hammers” to kick objects, safety boots with toe-caps often wear out prematurely in the toe region.
The premature wearing-out of the leather in the toe region, accentuated by the presence of toe-caps, resulted in shoe manufacturers adding a protective shell over the leather in the toe region. Such a protective shell, commonly referred to as bumper toe, is made of a resistant compound (e.g., polyurethane). By protecting the material of the upper where the upper would normally break and tear, protective shells enhance the durability of the item of footwear.
Some bumper toes are cemented to the uppers prior to the soling process and a portion of such bumper toes is folded and secured under the edge of the last. Some bumper toes are molded during the injection of a midsole in a direct-attach construction. None of these constructions have an extension below the edge of the last.
Therefore, there remains a weakness at the junction between the upper and sole as well as between the midsole and outsole, in the front-end region of the item of footwear. The front-end region is subject to abrasion and/or intense shocks. The weakness is particularly notable in footwear with a direct-attach construction, as this type of assembly accentuates the separation of the different parts of sole and of the sole from upper. Moreover, the use of a low density midsole and the addition of a puncture resistant plate (e.g., steel plate) may emphasize this problem.
Referring to
The boots 1 and 2 include a midsole 5, an outsole 6, with a joint 7 between the midsole 5 and the outsole 6. The joint 7 is typically trimmed so as to provide a smooth surface finish for the combination of the midsole 5 and the outsole 6.
There is illustrated by reference numeral 8 in
It is therefore an aim of the present disclosure to provide safety footwear addressing issues associated with the prior art.
It is a further aim of the present disclosure to provide a method for manufacturing such safety footwear.
Therefore, in accordance with the present application, there is provided an item of footwear comprising: an upper adapted to receive a foot of the wearer; a sole secured to a bottom surface of the upper; and a shell positioned on a front-end portion of the upper so as to cover the toe region of the upper, the shell having an extension projecting below a junction between the upper and the sole to cover at least the junction in the toe region of the sole.
Further in accordance with the present application, there is provided a method for assembling an item of footwear comprising: assembling an upper to a sole to form an item of footwear; positioning a shell on a toe region of the item of footwear such that the shell covers at least a junction between the upper and the sole; and securing the shell to the item of footwear; wherein assembling, positioning and securing are performed in any order.
Referring to the drawings, and more particularly to
The boot 10 has an upper 11 that receives the foot of the wearer. A sole 12 is the interface between the upper 11 and the ground. Although not shown, a toe-cap may be provided within the material of the upper 11, or above the material of the upper 11.
A protective shell 13, also known as bumper toe, is provided at the front end of the upper 11 so as to form a shell that will cover the upper material, and provide abrasion resistance and impact resistance to the upper material at the front-end of the boot 10. The protective shell 13 is made of a sturdy material and is preferably an integral piece (e.g., molded, cast). As shown in
The protective shell 13 optionally supports a head plate 15. The head plate 15 provides additional functions to the boot 10. For instance, in
Moreover, the head plate 15 may also be used as an impact zone for shock absorption when the wearer of the boot 10 uses the protective shell 13 as a tool to hammer/kick some items such as nails, wood trims or the like. With the bottom extension 14 extending below the joint or junction 16 between the upper 11 and the sole 12, the boot 10 may be used for this function without risking a separation of the various toe parts of the boot 10. The junction edge between the protective shell 13 and the sole 12, as illustrated at 17 in
Referring to
Referring to
The protective shell 13 may be used on an item of footwear that has a toe-cap under the upper, or may also replace the toe-cap altogether. In such a case, the protective shell 13 must have a robust structure, made of steel or like metals, high-density polymers or composite materials. The protective shell 13 may also be used on regular footwear, as opposed to safety footwear, to increase abrasion and shock resistance of the toe region of the footwear, without necessarily providing the toe protection offered by standard toe-caps.
It is pointed out that the protective shell 13 may be an extension of the sole, or a part of the sole (i.e., midsole, outsole), folded or molded over the front-end region of upper, thereby encapsulating a head plate with the upper. In such a case, the protective shell 13 is integral with the sole.
In order to manufacture the safety boot 10, processes are now described.
The protective shell 13 is cast or molded in suitable materials. Materials that offer high abrasion resistance and absorption qualities as well as a suitable friction coefficient for adherence are preferred. For instance, thermoplastic polyurethane (TPU) is the material that is typically used, as well as conventional materials such as steel, aluminum, composites or the like in the event that the protective shell 13 is used to replace the toe-cap under the upper. As for the head plate 15, a synthetic rubber (SBR) may be used, amongst numerous other materials. A cement is then used to secure the contact plate 15 to a remainder of the protective shell 13, as illustrated in
According to one process, the protective shell 13 is firstly adhered to the upper 11, by cementing, injection-molding or stitching, among numerous possibilities. The sole 12 is subsequently secured to the upper 11 in the manner shown in
The sole 12 may be secured to the upper 11 as described above prior to the protective shell 13 being assembled thereto. In such a case, the sole 12 is shaped in the toe region as a function of the protective shell 13 that will be mated thereto afterwards. Finally, the sole 12 may be added to the boot 10 in different steps. A midsole may first be secured to the upper 11 and to the protective shell 13, with an outsole being molded directly to the midsole afterwards. In another embodiment, the midsole may first be molded to the upper 11 and to the protective shell 13, with an outsole being secured to the midsole afterwards. Other sequences are considered as well.
It is also considered to mold separately an outsole with an extension on the front, the extension having an opening where a head plate is secured. Then, when assembling the sole to upper, the extension of the outsole is folded over the front-end of the upper to form a protective shell with a head plate exposed in the protective shell.
It is also considered to position the upper 11 and shell 13 on a last, and to subsequently secure the sole 12 to the upper and shell assembly. In such a case, it is considered to have a bottom edge of the extension of the shell 13 extend by at least 5 mm below the last. The sole 12 may be molded to encapsulate the bottom portion of the shell 13, in which case the bottom portion of the shell 13 is encapsulated in the sole 12.
The final product is an item of footwear featuring a protective shell that protects the toe region of the sole and upper against abrasion and impacts.
The present application claims priority on U.S. Provisional Application Ser. No. 61/106,651, filed Oct. 20, 2008.
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Number | Date | Country | |
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20100095549 A1 | Apr 2010 | US |
Number | Date | Country | |
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61106651 | Oct 2008 | US |