CZ25838U1 - Footwear with special middle sole - Google Patents

Description

Technical field

The technical solution concerns footwear with a special midsole favorably affecting the distribution of plantar pressures during walking and other movement in the front of the footwear. This type of midsole is most used for special prophylactic footwear for diabetics.

Background

Currently, prophylactic footwear for diabetics is intended for patients diagnosed with neuropathic or angiopathic foot. It is designed to prevent further undesirable development of irreversible changes on the feet of diabetics, and is generally produced in series. The main purpose of this footwear is to protect the diabetic's feet from the possibility of injury and defect. The size of plantar pressure plays one of the key roles in developing a defect in the diabetic foot. Therefore, one of the most important tasks of a prophylactic shoe is to spread the tread forces over the largest possible area of the foot and thus reduce the high local pressure on the planet.

Currently, the issue of reducing high plantar pressures in prophylactic footwear for diabetics is mainly solved by insert insoles. Manufacturers are trying to achieve decomposition of tread forces in different ways. Insoles that have a preformed footbed are used, see, for example, the solution according to Czech Patent No. 298894, which describes an insole of a shoe whose upper side is shaped into a relief in the form of a footprint of the human foot and whose underside has a lower foot Human foot parts with smooth toe. Principally similar is also the solution according to Czech utility model no. 16872, which also has a hole in the insole of the thumb joint. Insoles with the ability to shape according to the shape of the foot during wear are also used. Other special types include padding based on gel-filled parts - see, for example, the solution according to Czech patent application PV 2009-219 consisting in that the sewing insole has an anchored shaped part on the upper surface of its supporting layer, which has areas shaped depressions, in particular in the area under the toes, the area under the metatarsal bones, the area under the middle and rear edge of the foot and the area under the heel bone. The negative-positive principle fits into the shape of the raised and filled parts of the gel filler anchored in the lower moldable cushioning layer of the insole.

The purpose of all the above-mentioned insoles is to reduce the high local pressures arising as a side effect of the diabetic foot due to deformities and limited sensitivity.

This equipment, however, does not solve the problem if there is an increase in local pressure unevenness of the external terrain. In the event of tread on the unevenness of the areas of the foot, where local pressure is increased by the disease, the sum of these two phenomena sums up, resulting pressure can reach a very high value and may result in a single action to damage the soft tissues of the foot.

Experimental studies have shown that the best distribution of tread forces and damping of plantar pressures occurs in soles with high hardness and / or high thickness. Very good decomposition of the tread forces on the sole of the foot can be achieved by using a midsole of hard material, such as sheet metal, which is used in some types of work shoes as a safety feature in case of nail or other sharp objects. However, the use of this kind of midsole, as well as soles with a thickness greater than 2 cm, has negative consequences in terms of reduced flexibility of footwear.

The rigid sole principle is currently used, for example, in special footwear, where the rolling of the foot from the pad is made possible by a modified sole with a bevelled or cradled shape in the front. This footwear is suitable for diabetics who, for example, have had amputation of one or more toes, have reduced joint mobility, severe deformities of the front of the foot, etc. desirable rolling of the foot while walking to the extent that is common in a healthy population.

-1 CZ 25838 Ul

The essence of the technical solution

The disadvantages and drawbacks of the footwear solutions disclosed in the prior art description largely eliminate footwear with a special midsole favorably affecting the distribution of plantar pressures during walking and other movement in the front of the footwear according to the present invention.

The principle of the technical solution consists in that said special midsole is formed by the base piece of the bottom material, in which a system of rigid slats placed with its longer edges parallel to the axis of bend of the foot is inserted in the area under the heads of the bones.

The rigid lamella assembly preferably comprises 3 to 4 lamellae, which may preferably be made of a composite material such as a glass fiber or carbon fiber reinforced polyester or epoxy resin.

It is a design that contributes, as already mentioned, to a better decomposition of tread forces and helps to reduce high local pressures. At the same time, it has little effect on the flexibility of the shoe at the functional axis.

This bottom treatment is best suited for bonded footwear. In case of use for other manufacturing method, eg flexibile, it is necessary to correct the distance of the slats from the circumference of the midsole according to the bottom design.

BRIEF DESCRIPTION OF THE DRAWINGS

The attached drawing shows a detail of the special midsole with the placement of the slats in the base part and Fig. 2 the location of the special midsole in the footwear section.

Technical solution

The special midsole I in the exemplary embodiment of FIG. 1 corresponds in shape to the design of the bottom of the shoe. Its base part is made of two identical cuts of bottom material, lightweight rubber with a thickness of 3 mm. In one of the slits, an opening for the placement of the slats 2 is cut in the area of the toe joints. Both parts are glued together and a system of three slats 2 is glued into the created space so that the bending axis of the shoe is parallel to the longer edges 3 slats. between the slats 2. The slats 2 have a width s of 30 mm, a distance d from the edge of the midsole 1 equal to 5 mm and are made of a composite material based on glass or carbon fiber reinforced polyester or epoxy resin.

The placement of the formed midsole in the shoe is schematically shown in Fig. 2. The midsole with the already glued slats 2 is glued to the sole 4. The assembled shoes are then connected to the upper 5 with this design. compared to using footwear with a midsole of similar base material without special treatment. Modifying the midsole does not significantly reduce the consistency of the connection of the bottom components.

Industrial applicability

Shoes with a special midsole to reduce the size of plantar pressures according to the technical solution is primarily useful in the mass production of prophylactic footwear for diabetics. Further use is possible for those types of footwear that are desirable to provide a reduction in the amount of wear on the wearer's foot while maintaining sufficient flexibility.

Claims (3)

PROTECTION REQUIREMENTS 1. Footwear with a special midsole favorably affecting the distribution of plantar pressures during walking and other movement in the front of the footwear, using in particular as prophylactic footwear for diabetics, said midsole comprising a base panel of a base material, characterized in that In the region below the instep heads, a system of rigid slats (2), with their longer edges (3) parallel to the bend axis of the shoe, is inserted in the base panel of the midsole (1). The special midsole shoe according to claim 1, characterized in that the rigid slats (2) of the midsole (1) comprise 3 to 4 slats. io Special midsole shoes according to claim 1, characterized in that the slats (2) of the midsole (1) are made of a composite material, such as polyester or epoxy resin reinforced with glass or carbon fibers.