In the past there have been several attempts to develop many shoe constructions to reduce sweat of user's feet and to provide additional comfort to the users, but, by our point of view, the results were not satisfactory, both considering functionality, their design and manufactoring difficulties. For example some patents set forth an outer sole with many holes inside and a fitted waterproof innersole over said outersole, with microholes to leave air passage through but avoiding water drops permeation. In this case it is not considered that by walking, debris, mud, dust and so on, can clog these microholes, so that ventilation stops after a short period of use.
Other patents set forth outersoles construction with one or more one-way valves inside which air can pass through, stopping rain water permeation: also in this case these valves can be clogged by debris, mud, dust and so on, because they are in contact or too much close to the dirty surface of the road, so that after a short time of walking, they don't work anymore and the effectiveness of the ventilation diminishes soon.
Other patents set forth ventilated shoes with air inlet in the heel portion of the shoe but with a reduced air flow, not improved and increased by the pumped air of the protruding inner lining in the heel portion. These patents furthermore disclose shoe constructions with circulating air inside that can make wearing of the shoe more confortable, but failing to provide the shoe with inner air changeable flow depending upon time weather, cold in wintertime and hot in summer.
DE 100 41 113 discloses a shoe comprising a complex flat sole, adherent or integral with an outersole, provided with channels, holes and chambers. A duct is specifically provided to communicate said sole with an upper rear portion of the shoe. DE 90 16 428U discloses a flat inner sole provided with longitudinal and transversal channels communicating with some peripheral apertures. US2002/170203 discloses a shoe comprising an outersole provided with some recesses and channels, covered by an insert closing the recesses from the above and making them communicate with some channels in the sidewalls of the shoe. GB 2189679 discloses a ventilating mechanism to be removably inserted in the shoe or formed integrally with it; the mechanism comprises a complex insole element formed of a resilient material and having a pump integrally formed therewith, comprising a pump chamber, a plurality of valved inlet ports and valved outlet ports.
Furthermore some patents set forth shoe construction with some holes in the upper horizontal portion of the toe, but in this case, when it is raining, some rain drops can infiltrate into the shoe, wetting the user's feet.
Moreover these patents set forth shoe construction with a reduced air inner ventilation not only because they fail to provide the shoe with the rear heel air pump, as told above, but also they don't use upper sidewalls channels in combination, to add vented air to that one drawn into, through rear heel intakes.
It is considered necessary to disclose the shoe manufactoring steps to make easier understanding the industrial manufactoring difficulties of the patents shown above, where ventilation is provided through the air intake and channels in the heel rear portion.
Usual shoe manufactoring steps are following:    a) model design with cardboard elements mainly to cut upper different portions    b) hollow punchs manufactoring including that one for the counterfort to make harder the shoe heel.    c) upper different pieces cutting.    d) sewing and gluing of different upper pieces.    e) turning of the already sewed portions of the upper around the wooden shoe last, and mainly the heel outer upper, the counterfort and the inner lining, already glued among them, must be turned under the wooden last, to be glued or sewed to the outer sole.    f) pressing by the press machine of the upper already sewed and glued portions turned around the wooden last for outersole gluing. At this step a problem raises, when air channels are provided in the heel rear portion, because said air channels must be in connection and in perfect alignment with the channels and the air hollows under the inner sole, so that they should be inserted among rear outer upper, counterfort and inner lining, but at this manufactoring step this introduction is not possible because they are already glued among them, to get a well manufactured long life shoe.
By our point of view, patents above shown, have not considered these manufactoring industrial difficulties without detailing the manufactoring process and without trying to simplify the various manufactoring steps.
Present invention solves above drawbacks.
USPTO Backgrounds
USPTO Backgrounds