EP0780063A1

EP0780063A1 - Bottom for footwear with ventilating protuberances

Info

Publication number: EP0780063A1
Application number: EP96830628A
Authority: EP
Inventors: Luigi Marchetti
Original assignee: Ligmar Gomma - Srl
Current assignee: Ligmar Gomma - Srl
Priority date: 1995-12-22
Filing date: 1996-12-17
Publication date: 1997-06-25
Also published as: IT1281926B1; ITMC950136A1; ITMC950136A0

Abstract

This invention concerns a plastic moulded bottom for footwear whose upper surface has a series of hollow, flexible protuberances terminating with holes that exercise a ventilating and massaging action on the sole of the foot.

Description

This design patent application concerns a plastic moulded bottom for footwear whose upper surface has a series of hollow, flexible protuberances - which in a preferred embodiment are dome-shaped - terminating with holes that exercise a ventilating and massaging action on the sole of the foot.
The item in question is designed to make shoes more comfortable, especially in the case of shoes with a plastic moulded sole.
Although soles made of plastic material are extremely practical above all because they make footwear highly waterproof and offer a soft treading surface, they do however have a significant drawback since they do not allow the foot to transpire.
This is obviously a serious problem especially for those who are subject to heavy sweating.
To date various attempts have been made to overcome this serious limitation of plastic soles, without a great deal of success.
In most cases an attempt was made to apply small holes or grated areas on the upper of shoes with plastic soles of this kind in order to create a certain amount of air circulation for the foot.
Obviously this solution made the shoe somewhat unattractive, and has almost exclusively been used for sports footwear.
An alternative version was a plastic bottom with a series of holes along the edge which communicated with the resting surface of the foot; this solution created yet another inconvenience since the bottom was no longer waterproof.
Water in fact passes easily through these ventilation holes and the problem can only be solved by applying waterproof membranes to the holes but this solution makes manufacture of the shoes more complicated and costly.
A shoe bottom of this kind is described in patent DE U 94 07 864, which concerns a plastic moulded sole having an internal channelling composed of a parallel series of single transversal channels reaching both sides of the sole.
Each transversal channel intercommunicates with an overlying and corresponding row of holes and holed domes, made on the upper surface of the sole.
The scope of this invention is to design a plastic moulded sole which ensures automatic forced ventilation to the foot with each step the user takes.
This advantage has moreover been obtained without having to make holes on the outer surface of the shoe, upper or sole and consequently without compromising the appearance and/or practical qualities of shoes on which the bottoms according to the invention are fitted.
It is also interesting to note that technical means that ensure ventilation in the sole in question, also exercise a massaging action on the foot.
The sole in question is in fact characterised by a series of soft and flexible, hollow or dome-shaped protuberances on its upper surface.
The main feature of these protuberances is that hey have a hole at the top into which air circulates through the hollow and into the interior of the shoe.
Thanks to the position and disposition of these domes, whenever the shoe is pressed against the treading surface, the full weight of the user is placed on the domes.
This downward pressure flexes the structure of each dome and its internal cavity, which is thus alternatively pressed and dilated.
It is during this elastic flexion that the air in the cavity of each dome is rhythmically forced out through the hole at the top.
In view of the way the domes are compressed, it follows that each emits an authentic "micro jet" of forced air which directly strikes the sole of the foot at a very short distance, ensuring ventilation and consequently transpiration of the foot.
It is just as obvious that whenever the foot lifts from the treading surface and consequently whenever the pressure of the sole of the foot on the domes is released, the domes will automatically return to their natural shape.
During this phase, another elastic flexion occurs which is exactly opposite to the previous one and produces exactly the opposite effect; in other words, during this phase, the hollow of the dome fills with the air which is then forced out when the shoe is again pressed against the treading surface.
To explain the operating principle of the domes made on the sole according to the invention, more clearly the domes can be said to act like small pumps involving phases during which air is drawn from the interior of the upper alternated with phases during which the air previously drawn in is forced out.
Moreover, this continuous and alternating elastic flexion of the domes against the sole of the foot also produces the massaging action mentioned previously.
Finally, for reasons of hygiene, a thin cleaning insole with a series of through holes is fitted above the sole in question, in order to allow the air forced out of the holes to enter the interior of the upper.
In the case of moccasin type uppers, in other words sack shaped uppers, these holes must also be made on the section of upper which wraps the bottom of the foot, so that the same fits between the foot and the plastic sole itself. For major clarity the description of the invention continues with reference to the enclosed drawings which are intended for purposes of illustration and not in a limiting sense, where:

figure 1 is a transverse cross-section of the plastic sole according to the invention in monoblock version;
figure 2 is similar to the previous one but it refers to an alternative version of the sole according to the invention.

With reference to the enclosed figures, the moulded plastic sole according to the invention (1) has a bottom treading surface with tread (1a); this item features a series of hollow and flexible domes (2) on the upper surface, which have a hole at the top (2a).
These domes (2) may be made over the entire treading surface of the foot or only on the front of the foot and/or on the heel.
Attention should be drawn to the fact that the inner part (2b) of each dome (2) is closed by a bottom wall (2c), therefore said inner part communicates with the outside only through the holes (2a) provided on the side walls of the dome.
The sole in question may also be realised in different structural versions.
With reference to figure 1, an alternative version may be realised whereby the domes (2) are made in the same material and in the moulding phase of the sole (1), by means of a specially shaped mould.
Obviously in this version, the series of domes (2) would be incorporated to the structure of the sole (1).
With reference to figure 2, the sole itself (1A) may alternatively be moulded with a smooth surface on which a plastic moulded insole (3) with the same shape is applied; said insole (3) having the same hollow domes (2) with holes at the top (2a) and bottom wall (2c) on the upper surface and a smooth bottom surface which fits against the upper surface of the sole (1A) itself.
Finally, according to the same inventive design, the sole in question may be realised with hollow prutuberances of a different shape, even if with a similar functioning principle to that of the above domes; the protuberances could for example be of an elliptical or polygonal shape. In the same way additional holes may be realised on the sides of these protuberances or domes, in addition or to substitute the previously mentioned holes at the top.

Claims

A shoe bottom moulded in plastic material including a thick series of hollow, flexible protuberances (2) fitted with one or several holes (2a) and placed on the upper surface of the bottom, characterised in that each protuberance (2) is closed by a bottom wall (2c), therefore the inner part (2b) of each protuberance (2) can communicate with the outside only through the abovementioned holes (2a) made on the side walls of the protuberances (2).
A shoe bottom moulded in plastic material according to claim 1), characterised in that the above protuberances (2) are positioned over the entire upper surface.
A shoe bottom moulded in plastic material according to claim 1) characterised in that the above protuberances (2) are positioned over only half of the front sole and on the heel.
A shoe bottom moulded in plastic material according to claim 1) characterised in that the above protuberances (2) are incorporated into the bottom itself, said protuberances being produced in the same moulding material and phase with the bottom.
A shoe bottom moulded in plastic material according to claim 1) characterised in that the above protuberances (2) are made on the upper surface of an insole (3) having a bottom face with continuous surface which is applied above the bottom itself having for this purpose a smooth upper surface.