Unidirectional airflow ventilating shoe and a unidirectional airflow ventilating insole for shoes

A unidirectional airflow ventilating shoe having a ordinary upper and sole. A unidirectional airflow ventilating layer (1) is provided on the sole inside the shoe. The ventilating layer has an compressible cavity (2), air inlet (3), main airflow passage (4), branches (5) and air outlets (6). Fresh air outside the shoe is forcedly unidirectionally sucked into the ventilating layer and blown out to fore part inside the shoe. To convenience sake, a unidirectional airflow ventilating insole can be made for any kind of shoes. The insole comprise a upper portion (7) and lower portion (8). The structure and shape of the upper portion is the same that of the ventilating layer (1). Lower portion (8) can either form an entirety with upper portion (7), or be an elastic substrate athered to the bottom surface of the upper portion with adhesines. The insole can be used in any kind of shoes and attain the same result as unidirectional airflow ventilating shoes of the present invention.

This invention relates to a kind of shoe, in particular, to a kind of 
unidirectional airflow ventilating shoe and unidirectional airflow 
ventilating insole for shoes. 
The existing air-blow shoes (FR Nos. 2543803, FR 2548527, DE 3336605 and JP 
58-130002) focus on either improving the air permeability or accelerating 
air permeability by increasing the circulation of air within the shoes. As 
a result, replacement of fresh air is not possible until the gas in the 
shoes is discharged and therefore the rate of air permeability is very 
low. Other kinds of shoes with air-pump, such as DE Nos. 3206631, JP 
57-134102, GB 2098851, are better ventilated than the air-blow shoe 
mentioned above. However, the production process thereof is more 
complicated due to the adoption of an pump and check valve, and since 
extra materials are required, the production cost and market price are 
increased. Moreover, the technique for producing the air-pump shoes is not 
applicable to casual and sports shoes because the adoption of the pump and 
valve will make the wearer uncomfortable. Up till now, only one type of 
such air-pump shoes is manufactured in Taiwan. As metallic spring and 
ebonite are used for adopting the pump body and valve thereof, only shoes 
with hard soles of complicated structure and high cost can be 
manufactured. 
The object of the present invention is to provide a kind of unidirectional 
airflow ventilating shoe and unidirectional airflow ventilating insole for 
shoes, wherein fresh air outside the shoes is forced unidirectionally into 
the front part of the feet so as to attain higher rate of ventilation. 
As far as the appearance, the sole and the structure of the upper part of 
the shoes are concerned, there are no difference between the ventilating 
shoes of the present invention and ordinary shoes. To achieve the object 
of the invention, there is a unidirectional airflow ventilating layer on 
the sole inside the shoe. The hell portion of the layer is provided with a 
compressible cavity at the bottom surface of the layer. The back upper 
portion of the layer is provided with a elastic closable air inlet and the 
front portion with a elastic main airflow passage leading to the front 
part of the layer. The fore end of the main airflow passage is splitted up 
into several branches. The fore end of each branch is provided with an air 
outlet leading to the upper surface of the layer.

It can be seen from FIG. 1 that the unidirectional airflow ventilating 
layer (1) of a unidirectional airflow ventilating shoe is a sole-shaped 
elastic material consisting a thick heel portion and thin front portion, 
the bottom surface of the elastic material being pressed closely to the 
sole (9) of the shoe. As shown in FIG. 2, a cavity (2) is provided in the 
heel portion. 
The cross-section of the cavity is arch-shaped, with the peak point of the 
arch being about 3/4 of thickness of the heel portion and the miximum 
section area of the arch about 4/5 of the section area of the heel 
portion, thus guaranteeing a certain capacity and mantaining a 
considerable degree of elasticity. An air inlet (3) is opened up 
backwardly at the back upper portion of the cavity (2). 
As illustrated in FIG. 1, the heel portion has a back wall in which an air 
inlet (3) opening to the rear area of the shoe resides in such a manner 
that when force is applied to the head portion of the layer, the air inlet 
(3) is closed as a result of the back wall collapsing. The cross-section 
of air inlet (3) in FIG. 3 is in the shape of a sharp leaf so that it can 
be completely closed under pressure. 
A main airflow passage (4) is opened up from the front of the cavity (2) to 
the fore sole (FIG. 2). The cross-section of main airflow passage (4) is 
arch-shaped and the ratio of the height and width is 1:3. The passage is 
completely closed when bent. As shown in FIG. 2, the main airflow passage 
(4) is divided into branches (5) at the front end thereof, preferably 2-4 
branches. The cross-section of branches (5) are preferably in the shape of 
semi-circles. A cylindrical air outlet (6) is opened up at the front end 
of each branch (5) and directed at the root of the toes in the shoe (FIG. 
3). The entire layer (1) can be stuck onto the sole of the shoe. 
While the wearer walks, the heel portion will touches the ground first, as 
shown in FIG. 4. Air inlet (3), being located at the part which first 
touches the ground, will be closed under heavy pressure of the wearer as 
illustrated in FIG. 5. It can be seen from FIG. 6 that with the centre of 
gravity being shifted forward, the point of the shoe which touches the 
ground will also be moved forward. In the meantime, cavity (2) is 
compressed from the back to the front and the air in the cavity is flowing 
out through main airflow passage (4), branches (5) and air outlet (6) to 
the front part of the shoe, and then flowing out through the eyelet, the 
gaps between the tongue and the edge of the shoe's upper. 
When the heel portion is lifted and the fore sole touches the ground, the 
shoe is bent. That will cause main passage (4) to be bent and closed. In 
this way, air in the fore part is hindered from going back into cavity (2) 
and therefore the air only goes in one direction. Concurrently, air inlet 
(3) is elastically opened. The fresh air outside is sucked into cavity (2) 
through the gap between edge of shoe's upper and the foot heel (FIG. 7). 
As a result, a process of unidirectional airflow ventilating is 
accomplished in every step the wearer takes. 
For convenience sake, this invention also provides a undirectional airflow 
ventilating insole comprising upper insole (7) and lower insole (8), as 
shown in FIG. 8. The structure of upper insole (7) is the same that of 
ventilating layer (1) of said unidirectional airflow ventilating shoes. 
Cavity (2), air inlet (3), main airflow passage (4), airflow branches (5) 
and air outlet (6) are provided in a piece of elastic material. Lower 
insole (8) can either form an entirety with upper insole (7), or be an 
elastic substrate in the form of a sole closely sealed to the bottom 
surface of the upper insole. 
A pair of unidirectional airflow ventilating shoes can be made without 
increasing material cost by replacing the middle soles of such soft-sole 
shoes as ordinary walking shoes and sport shoes with the unidirectional 
airflow ventilating insole. In applying the ventilating insole to boots, 
an air channel provided at the upper of each boot and connected with the 
air inlet of the ventilating insole is enough to change a ordinary boot to 
a unidirectional airflow ventilating boot. Using the ventilating insole in 
any kind of shoes can attain the same result as unidirectional airflow 
ventilating shoes. 
The present invention has several distinctive advantages. For example high 
rate of ventilating can be accomplished by fresh air outside shoes 
unidirectionally flowing into the front part, which is the dampest and 
hottest part inside the shoe, so that the wearer can feel wind blowing 
towards his feet. This feature also helps prevent stink and disease of 
feet. Besides, since the material used is cheap and the structure is 
simple, the manufacturing process is convenient and the production cost is 
low. As no pump body or valve is required, such kind of shoes are 
comfortable to wear and the insole is suitable to be used with shoes of 
all classes, regardless of the materials used for the vamp and sole, the 
thickness of the heel and the height of the upper part of the shoes. 
A further merit of the invention is that people suffering from foot disease 
may spray medical lotion frequently into the unidirectional airflow 
ventilating layer of the shoe or the cavity and airflow passage of the 
ventilating insole. As a result, the medical lotion would be blown to the 
fore part of the feet while the wearer walks. Furthermore, perfume may 
also be sprayed into the cavity and passage so as to prevent the feet from 
stinking. 
Two specific embodiments are described hereunder: 
The first embodiment is a unidirectional airflow ventilating shoe. 
A 30 mm thick PVC (polyvinyl ehloride) or PU (polyurethane) piece is cut 
into the shape of a sole with the front part cut to 8 mm thick and the 
longitudinal section being in the form of a right-angled trapezium. A 
arched cavity is excavated at the heel part with the thickest part is 22 
mm. The external edge of the cavity has 8 mm wide allowances and the 
capacity of the cavity is approximately 6000 mm.sup.3. A arch-shaped main 
airflow passage excavated at the front of the cavity is 3 mm tall and 12 
mm wide and is divided into at least two branches as it reaches the front 
sole; each of said branches is 3 mm tall and 6 mm wide. Cylindrical air 
outlets which have diameters of 6 mm are vertically excavated at the front 
end of each branch, penetrating the piece. Air inlet with tapered 
leaf-shaped cross-section which are 18 mm wide and 5 mm tall is excavated 
at the rear upper part of the cavity. The air inlet penetrate backwards 
the piece. Taking out the middle sole and inner lining cloths of a 
readymade sports shoe with low upper, applying adhesives all over the sole 
of the shoe and sticking the excavated surface of the above manufactured 
piece on the sole, than a unidirectional airflow ventilating shoe will be 
formed. An experiment shows that about 5000 mm.sup.3 fresh air is blown 
out of the outlets with each step the wearer takes. 
The second embodiment is a unidirectional airflow ventilating insole for 
shoes. 
A 20 mm thick synthetic rubber piece is used as a upper insole. The same 
processing technique used in the first embodiment is employed. Since the 
elasticity of rubber is stronger, the thickness of the synthetic rubber 
can be thinner. The front part is cut to 6 mm thick and the capacity of 
the cavity is about 4000 mm.sup.3. The arch-shaped main airflow passage is 
2 mm tall and 12 mm wide; each of branches is 2 mm tall and 6 mm wide. The 
sharp leaf-shaped air inlets is 18 mm wide and 3.5 mm tall. The air 
outlets are cylindrical which have diameters of 6 mm. Using 1.5 mm thick 
soft plastic pieces as a lower insole and adhering the lower insole 
tightly to the excavated surface of the upper insole with adhesives, then 
a unidirectional airflow ventilating insole is formed. The ventilating 
insole can be used in any kind of shoes and about 3000 mm.sup.3 fresh air 
is blown out of the air outlets with each step while walking. 
The above embodiments are only examples for describing the present 
invention. They should not have any limitations on this invention, i.e. 
simple improvements or alterations made by persons skilled in the art 
within the scope defined by the claims should be understood as not going 
beyond the scope of the invention. For instance, alterations can be made 
on the sizes of the cavity, the main airflow passage, the branches and the 
air outlets of the unidirectional airflow ventilating shoes or the 
ventilating insole corresponding to the sizes of various kinds of shoes. 
The numbers of branches and air outlets can also be increased or reduced, 
etc.