Patent Publication Number: US-2022225725-A1

Title: Waterproof Boot With Internal Convection System

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional of U.S. application Ser. No. 16/429,617, filed Jun. 3, 2019, which claims the benefit of the filing date of U.S. Provisional Application No. 62/680,231 filed Jun. 4, 2018, the disclosures of which are hereby incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present technology relates in general to waterproof footwear that incorporates an improved pump-ventilation mechanism. Waterproof footwear is generally constructed with an upper that is substantially impermeable to water and which, in many instances, extends up over the ankle or even higher on the leg. Such footwear is useful for many applications, particularly in outdoor work and sporting activities such as construction, fishing, hiking, hunting and the like. While such waterproof footwear may protect a wearer&#39;s foot from water, the waterproof material of the upper is also likely to prevent airflow through the walls of the upper. Because the upper may extend over the ankle and higher, airflow over a significant portion of the wearer&#39;s foot and leg may be blocked. This inhibits convective cooling of the wearer&#39;s foot and lower extremities, resulting in footwear that becomes hot, sweaty, and uncomfortable during use, particularly when the wearer is continuously walking or otherwise active. As waterproof footwear is often used during strenuous outdoor activity, this lack of ventilation may pose a significant problem. 
     BRIEF SUMMARY OF THE INVENTION 
     Accordingly, aspects of the present technology provide a substantially waterproof shoe having a ventilation mechanism which coordinates with specially designed airflow channels in the upper to circulate air from the outside environment through the shoe in order to provide convective cooling of a wearer&#39;s foot during movement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a longitudinal cross-sectional view of a shoe in accordance with aspects of the present technology. 
         FIG. 2A  is a top-down view of an outsole and midsole in accordance with aspects of the present technology. 
         FIG. 2B  is a lateral cross-sectional view of toe and heel portions of an outsole and midsole in accordance with aspects of the present technology. 
         FIG. 2C  is a view of the bottom surface of an outsole in accordance with aspects of the present technology. 
         FIG. 3A  is a view of a ventilation mechanism in accordance with a preferred embodiment of the present technology. 
         FIG. 3B  is a longitudinal cross-sectional view of a shoe in accordance with aspects of the present technology, with particular emphasis on channels configured to provide airflow from and to the outside environment. 
         FIG. 4A  is an expanded view of a ventilation mechanism in accordance with an alternative embodiment of the present technology. 
         FIG. 4B  is a top down perspective view of a ventilation mechanism in accordance with an alternative embodiment of the present technology. 
         FIG. 5A  is a top down view of a midsole and bottom surface of a ventilation mechanism in accordance with an alternative embodiment of the present technology. 
         FIG. 5B  is a top down view of a shank and top surface of a ventilation mechanism in accordance with an alternative embodiment of the present technology. 
         FIG. 6  is a bottom up perspective view of a ventilation mechanism in accordance with an alternative embodiment of the present technology. 
         FIG. 7A  is a view of the bottom surface of an insole of a shoe in accordance with aspects of the present technology. 
         FIG. 7B  is a view of the top surface of an insole of a shoe in accordance with aspects of the present technology. 
         FIG. 8A  is a side view of a shoe in accordance with aspects of the present technology. 
         FIG. 8B  is a front view of a shoe in accordance with aspects of the present technology. 
         FIGS. 9A-B  are views of a protective toe cap of a shoe in accordance with aspects of the present technology. 
         FIG. 10  is a view of a liner of a shoe in accordance with aspects of the present technology. 
         FIG. 11  is a chart showing the temperature of a wearer&#39;s foot over time, as a result of the test set out in Example 1. 
         FIG. 12  is a chart showing the temperature of a wearer&#39;s foot over the course of several hours, as a result of the test set out in Example 2. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the present technology provide a waterproof shoe with an improved ventilation mechanism, designed to circulate air from the outside environment through the shoe in order to provide convective cooling to a wearer&#39;s foot. In a desired embodiment, the shoe may incorporate a pump-ventilation mechanism which, coupled with airflow channels incorporated in the upper, acts to establish continuous substantially one-way airflow through the shoe in a heel to toe direction while a user walks. 
     As shown in  FIG. 1 , an exemplary shoe  100  includes: an outsole  200 , a midsole  300 , a ventilation mechanism  400 , a baseboard  500 , an insole  600 , an upper  700 , a protective toe cap  800 , ankle pads  900 , a lining  1000 , and airflow channels  1100 . 
     The outsole  200  has a bottom surface configured to contact the ground and a top surface configured to be secured to the midsole  300 . The midsole  300  has a bottom surface configured to be secured to the outsole  200  and a top surface configured to be secured to the upper  700 . In some aspects, the midsole  300  may include an embedded shank which has a top surface which is generally flush with the top surface of the midsole  300  and a bottom surface which may extend into the top surface of midsole  300 . 
     In a preferred embodiment, the ventilation mechanism  400  may be a separate component from the midsole  300  or baseboard  500 . In such an embodiment, the ventilation mechanism  400  may be disposed within a cavity in the top surface of the midsole  300  and has a top surface which sits flush with the top surface of the midsole  300  and a bottom surface which extends into the cavity. The ventilation mechanism  400  generally comprises three components: an intake reservoir  410 , an exhaust reservoir  430 , and a connecting channel  450 . The intake reservoir may be disposed in a heel region of the midsole  300  and the exhaust reservoir may be disposed in a toe region of the midsole  300  with the connecting channel running between them, so that they are placed in fluid communication with one another. In alternative embodiments, the ventilation mechanism  400  may be formed integrally within the midsole  300 , baseboard  500 , or, optionally, a removable insert  470  of the shoe. In some embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. 
     The baseboard  500  may be a substantially planar member having a bottom surface configured to contact the top surfaces of both the midsole  300  and, in some embodiments, the ventilation mechanism  400  and a top surface configured to contact the insole  600 . The baseboard  500  may be permanently secured to the midsole  300  by an adhesive. 
     The insole  600  may be a flexible insert which has a bottom surface configured to contact the baseboard  500  and a top surface configured to receive the foot of a wearer. In some aspects, the insole  600  may be removable from the shoe  100 . 
     The upper  700  may be substantially waterproof and extends upwards from the midsole  300  to form a cavity configured to receive a user&#39;s foot. The upper  700  has an inner surface which may be configured to receive a wearer&#39;s foot and promote air flow within the shoe  100  and an outer surface which may be configured to repel water and otherwise interact with the outside environment. In some embodiments, the upper  700  may additionally include a tongue portion having a ventilation channel running in a longitudinal direction. 
     The protective toe cap  800  may comprise a hemi-dome shaped body sized and shaped to cover a wearer&#39;s toes, so as to protect them from impact with obstacles, falling objects, and the like. The protective toe cap  800  may have an outer surface configured to be permanently secured to the inner surface of the upper  700  and an inner surface configured to receive and protect a wearer&#39;s toes. The protective toe cap may further comprise a ventilation channel extending in a longitudinal direction between a forefoot area and a midfoot area of the shoe. 
     The ankle pads  900  may comprise raised polygonal pads which may be permanently affixed to the inner surface of the upper on opposing lateral sides in ankle regions of the upper of the shoe. 
     The lining  1000  may be a porous fabric lining which may be disposed on the inner surface of the upper  700 , overtop of the protective toe cap  800  and the ankle pads  900 , such that it covers both of these elements as well as the entire inner surface of the upper  700 . The lining  1000  may be permanently secured in position by stitching to the upper  700 . 
     The ankle pads  900 , lining  1000 , and the upper  700  may be positioned to define airflow channels which are held away from close contact with the foot and ankle of a wearer so as to allow intake and exhaust of air from and to the outside environment in cooperation with the ventilation channel of the protective toe cap  800 . 
     Outsole 
     As depicted in  FIGS. 2A-C , the outsole  200  has a bottom surface  210  configured to contact the ground and a top surface  230  configured to be secured to the midsole  300 . 
     As shown particularly in  FIGS. 2A and 2C , the bottom surface  210  of the outsole may have a tread pattern  211  which is configured to prevent slipping on wet, oily, uneven, or irregular surfaces. Such a tread pattern may include raised ridges or lugs  213  of a generally polygonal shape such as diamonds, triangles, rectangles, squares, and the like. The tread pattern may include deeply cut channels  215  in between the raised portions in order to provide increased friction and grip of wet surfaces in particular. In addition, the bottom surface of the outsole may include a concave section  217  in a midfoot portion of the outsole  200  configured to correspond with the arch of the foot. This concave section may include a series of lateral ridges, designed to increase friction and grip. In some embodiments, a heel portion of the bottom surface of the outsole may jut out sharply from this concave section to create a lip  219 . Lip  219 , along with the ridged pattern of the concave section  217  may be configured to allow a wearer to securely stand, grip, and/or move on narrow surfaces such as a ladder or the edge of a shovel. 
     In some aspects, as shown in  FIGS. 2B-C , the bottom surface  210  of the outsole may further comprise a raised platform  212  in a heel region which protrudes beyond the adjacent areas of the bottom surface  210  of the outsole. The raised platform  212  may be configured to contact the ground first as a wearer begins a stride and then to flex upwards in the direction of the wearer&#39;s foot, so that the adjacent surfaces of the outsole may contact the ground as the wearer&#39;s weight is applied to the heel. In some aspects, the raised platform may be positioned in a region of the outsole which lies directly adjacent and beneath the intake reservoir  410 . In such a configuration, when the raised platform  212  flexes upwards, it may provide pressure on the bottom surface  411  of the intake reservoir  410 , causing it to compress. 
     The outsole  200  may be comprise an elastomer, including a thermoplastic polyurethane (TPU), a rubber, a polyurethane (PU), an ethyl vinyl acetate (EVA), or any combinations thereof. Such materials are beneficial in that they are oil and slip resistant and also do not tend to mark or stain other surfaces such as flooring and cement. 
     Midsole 
     As depicted in  FIGS. 2A-B , the midsole  300  has a bottom surface  310  configured to be secured to the outsole  200  and a top surface  330  configured to be secured to the upper  700  along the edges. The bottom surface  310  of midsole  300  may be permanently secured to the outsole  700  by an adhesive or, alternatively, by stitching, welting, or direct attachment such as injection molding. 
     In a preferred embodiment shown in  FIGS. 2A-B , the top surface  330  of midsole  300  may include a specially formed cavity  350 , designed to receive the ventilation mechanism  400 . Cavity  350  may be configured to be a precise fit for ventilation mechanism  400  and therefore may have a shape corresponding to that of the ventilation mechanism  400 , including a chamber  351  in a heel portion of the shoe to receive the intake reservoir  410 , a chamber  353  in a toe portion of the shoe to receive the exhaust reservoir  430 , and a channel  355  running between the intake reservoir  410  and the exhaust reservoir  430  to receive the connecting channel  450 . In other embodiments, portions of ventilation mechanism  400  may be integrally formed in midsole  300 . 
     The midsole  300  may be formed of any suitable material such as EVA, PU, TPU, polyolefin, or any combinations thereof. In some aspects, the midsole  300  may include an embedded shank  370  running in a longitudinal direction which is configured to provide stability and durability to the shoe. The embedded shank  370  may have a top surface which is generally flush with the top surface of the midsole  330  and a bottom surface which may extend into the midsole  300 . The shank  370  may be formed from any suitable material such as steel, nylon, fiberglass, TPU, or polyvinyl chloride (PVC). 
     Ventilation Mechanism 
     The ventilation mechanism  400  is designed to pump air from the outside environment through the interior of the shoe in a single direction while a wearer is walking, so that the wearer&#39;s foot may be subjected to convective cooling. In general, the ventilation mechanism  400  comprises an intake reservoir  410 , an exhaust reservoir  430 , and a connecting channel  450  connecting the intake reservoir  410  and the exhaust reservoir  430 . In some embodiments, the connecting channel  450  is configured to facilitate substantially one-way air flow in a direction from the intake reservoir  410  to the exhaust reservoir  430 . 
     A preferred embodiment is shown in  FIGS. 3A-B . As depicted in  FIG. 3A , in a preferred embodiment, the ventilation mechanism  400  may be a separate hollow insert which may be housed within cavities  351 ,  353 ,  355  in the top surface of the midsole  300 . In such an embodiment, the ventilation mechanism  400  may be formed from a material such as TPU or PVC. 
     As shown in  FIG. 3B , the intake reservoir  410  may be positioned within a corresponding cavity  351  in the heel region of the midsole  300 . The intake reservoir  410  has a top surface  413  which may be substantially planar and flush with the top surface  330  of the midsole and a nonplanar bottom surface  411  which may extend into the cavity  351  of the midsole from the top surface  413  so as to form a sealed, hollow intake reservoir between the two surfaces. The bottom surface  411  may extend into the cavity of the midsole to a depth, where the depth is the maximum distance between the top and bottom surfaces of the intake reservoir. The depth may be within the range of about 0.5 to about 2.5 cm, more preferably about 0.5 to about 1.5 cm, and in a preferred embodiment is about 2 cm. The volume of the intake reservoir  410  may be within the range of about 5 cm 3  to about 40 cm 3 , more preferably about 15 cm 3  to about 30 cm 3 , and in a preferred embodiment within about 20 cm 3  to about 30 cm 3 . In a preferred embodiment, the top surface  413  of the intake reservoir  400  may be in the shape of a half-oval to mimic the contours of the heel of the shoe  100 . However, the shape of the top surface  413  of the intake reservoir is not particularly limited and may be semicircular, circular, square, rectangular, oblong, or generally polygonal. 
     As shown in  FIG. 3A , the top surface  413  of the intake reservoir  410  may include one or more perforations  415  which allow for air intake. The intake reservoir  410  may also contain an expanded foam material  417 . Foam material  417  may be formed of expanded or porous materials such as EVA, PU, expanded TPU, or polyolefin. The foam material  417  may have a density/porosity within the range of about 80% to about 95%, more preferably about 80% to about 95%, or most preferably about 90% to about 95%. In some aspects, the intake reservoir  410  may be entirely filled with the foam material  417 . In other aspects, the foam material  417  may occupy only 90% or less, 80% or less, or 70% or less of the volume of the intake reservoir. In a preferred embodiment, the foam material  417  only occupies 80% or less of the volume of the intake reservoir. In a preferred embodiment, as shown in  FIG. 3A , the intake reservoir  410  is filled with foam  417  in sections where there is not a perforation  415  in the top surface  413  of the intake reservoir. In other words, where a perforation  415  is disposed in a section of the top surface  413 , the volume of the intake reservoir  410  immediately below to this section, is free from the foam material  417 . 
     The intake reservoir  410  and the foam material  417  are configured to be flexible and resilient such that when the top surface  413  of the intake reservoir is depressed, such as by the pressure of a wearer&#39;s heel during the beginning of a stride, the intake reservoir  410  is compressed and its volume decreases by at least 50%, more preferably by at least 60%, or in a preferred embodiment by at least 70%. When the pressure to the top surface  413  is removed, i.e. as the wearer transfers their weight to the forefoot as the stride progresses, the intake reservoir  410  and the foam material  417  are configured to rebound to their original shape and volume causing air to be drawn in through the intake perforations  415  in the top surface  413 . 
     As shown in  FIG. 3B , in a preferred embodiment, the exhaust reservoir  430  may be positioned within the corresponding cavity  353  in the toe region of the midsole  300 . In alternative embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. The exhaust reservoir  430  has a top surface  433  which may be substantially planar and flush with the top surface  330  of the midsole and a nonplanar bottom surface  431  may extend into the cavity  353  of the midsole from the top surface  433  so as to form a sealed, hollow exhaust reservoir between the two surfaces. The bottom surface may extend into the cavity of the midsole to a depth. The depth may be within the range of about 0.1 to about 1.0 cm, more preferably about 0.1 to about 0.5 cm, and in a preferred embodiment is about 0.2 cm. The volume of the exhaust reservoir may be within the range of about 2.8 cm 3  to about 28 cm 3 , more preferably about 2.8 cm 3  to about 14 cm 3 , and in a preferred embodiment within about 2.8 cm 3  to about 5.6 cm 3 . In a preferred embodiment, the top surface of the exhaust reservoir  430  may in the shape of a half-oval to mimic the contours of the toe of the shoe  100 . However, the shape of the exhaust reservoir  430  is not particularly limited and may be semicircular, circular, square, rectangular, oblong, or otherwise generally polygonal. 
     In a preferred embodiment, the top surface  433  of the exhaust reservoir may include one or more perforations  435  which allow for air exhaust. In some aspects, the exhaust reservoir  430  may further include one or more directional flow channels  490 . Such channels may be formed in the exhaust reservoir  430  so that they run in a longitudinal direction from the edge of the exhaust reservoir  430  closest to the heel of the shoe  100  to the edge of the exhaust reservoir  430  closest to the toe of the shoe  100 . These channels are designed to facilitate substantially one-way air flow in a heel-to-toe direction. Each directional flow channel  490  comprises a main channel  491  extending in a substantially linear longitudinal direction, as well as multiple angled conduits  493  extending from the main channel on either longitudinal edge. The angled conduits  493  have a dead end or cul-de-sac configuration and their length is about 10% to about 40%, more preferably about 20% to about 30%, or most preferably about 25% to about 30% of the length of the main channel  491 . The angled conduits  493  are positioned at an angle to the main channel  491  that is within the range of about 1 to about 90 degrees, more preferably about 30 to about 60 degrees, and most preferably about 40 to about 50 degrees, when measured in the desired direction of air flow. The angled conduits  493  may provide for generally laminar flow down the main channel  491  in a heel-to-toe direction, but create obstructed turbulent flow in the opposite direction, thus effectively facilitating heel-to-toe air flow and inhibiting toe-to-heel air flow. The perforations  435  in the top surface of the exhaust reservoir are positioned at the end of the directional flow channel  490  which is closest to the toe region. Thus, in order for air to exit these perforations  435 , it easily flows through the directional flow channel  491  in a heel-to-toe direction. Conversely, air intake through these perforations  435  would require the air to flow in a toe-to-heel direction, which is inhibited by the directional flow channels  490 . 
     As shown in  FIGS. 2A and 3A -B, the ventilation mechanism  400  of the preferred embodiment may further comprise the connecting channel  450  which runs longitudinally from the intake reservoir  410 , which may be located in a heel region, to the exhaust reservoir  430 , which may be located in a toe region, so that the two reservoirs are in fluid communication with one another. In some embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. The connecting channel  450  may be positioned within the corresponding cavity  355  running longitudinally through a midfoot section of the midsole  300 . The connecting channel  450  has a top surface  453  which may be substantially planar and flush with the top surface  330  of the midsole and a nonplanar bottom surface  451  which may extend into the cavity  355  of the midsole from the top surface  453  so as to form a sealed, hollow tube or channel between the intake and exhaust reservoirs. The bottom surface  451  may extend into the cavity  455  of the midsole to a depth, where the depth is the maximum distance between the top and bottom surfaces of the intake reservoir. The depth may be within the range of about 0.05 to about 0.5 cm, more preferably about 0.2 to about 0.5 cm, and in a preferred embodiment is about 0.4 cm. The cross sectional area of the connecting channel  450  may be within the range of about 0.02 cm 2  to about 0.1 cm 2 , more preferably about 0.02 cm 2  to about 0.08 cm 2 , and in a preferred embodiment within about 0.02 cm 2  to about 0.04 cm 2 . In a preferred embodiment, a cross sectional shape of the connecting channel  450  is rectangular. However, the cross sectional shape of the connecting channel  450  may be semicircular, circular, square, oblong, or otherwise generally polygonal. In some aspects, the connecting channel  450  may comprise a directional flow channel  490 . 
     In some aspects, the connecting channel  450  may connect the intake reservoir  410  to the directional flow channels  490  of the exhaust reservoir  430 . Thus, during a stride, the intake reservoir  410  may be compressed by the downwards pressure of the wearer&#39;s heel and the upwards pressure of the raised platform  212  of the outsole  200 , expelling the air held within into the connecting channel  450  and through the directional flow channels  490  to be exhausted through the perforations  435  at the end of the directional flow channels  490 . As the wearer transfers weight to the toe during a stride, the pressure on the intake reservoir  410  may be relieved causing the intake reservoir  410  to expand and refill with air through the perforations  415  in its top surface in order to begin the process again. Because the directional flow channels  490  facilitate air flow in a heel-to-toe direction and inhibit air flow in a toe-to-heel direction, the intake reservoir  410  is primarily refilled from air entering the perforations  415  in the intake reservoir  410  rather than from air flowing into the perforations  435  in the exhaust reservoir  430 . More specifically, in a preferred embodiment, the directional flow channels  490  provide for about 65% to about 90% (by volume) refill of the intake reservoir  410  from the perforations  415  in the intake reservoir  410 , based on the total volume of air which refills the intake reservoir  410 . More preferably, at least 75% of the refill volume comes from the perforations  415  in the intake reservoir  410 , and most preferably about 75%-80%. Thus, the ventilation mechanism  400  provides for continuous, substantially one-way air circulation through the shoe. 
     An alternative embodiment is depicted in  FIGS. 4A-B . This alternative embodiment provides a ventilation mechanism  400  which generally comprises an intake reservoir  410 , an exhaust reservoir  430 , and a connecting channel  450 . However, these components are formed integrally into the midsole  300 , shank  370 , and baseboard  500  of the shoe. Specifically, the bottom surfaces of an intake reservoir  411 , an exhaust reservoir  431 , and a connecting channel  451  may be formed by depressions in the top surface of the shank  370 . Thus, the shank may be embedded into midsole such that the intake reservoir  410  may be positioned within a corresponding cavity in the heel region of the midsole  351 , the exhaust reservoir  430  may be positioned in a corresponding cavity  353  in the toe region of the midsole, and the connecting channel  450  may be fitted into a cavity  355  running longitudinally between the heel and toe regions of the midsole  300 . In some embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. 
     The bottom surface of intake reservoir  410  formed in the shank  370  may extend into the cavity  351  of the midsole  300  to a depth, where the depth is the maximum distance between the top and bottom surfaces of the intake reservoir. The depth may be within the range of about 0.5 to about 2.5 cm, more preferably about 0.5 to about 1.5 cm, and in a preferred embodiment is about 2 cm. The volume of the intake reservoir  410  may be within the range of about 5 cm 3  to about 40 cm 3 , more preferably about 15 cm 3  to about 30 cm 3 , and in a preferred embodiment within about 20 cm 3  to about 30 cm 3 . In a preferred embodiment, the intake reservoir  410  may be in the shape of a half-oval to mimic the contours of the heel of the shoe  100 . However, the shape of the top surface of the intake reservoir  410  is not particularly limited and may be semicircular, circular, square, rectangular, oblong, or generally polygonal. In some embodiments, the intake reservoir  410  may include one or more lugs  460  which extend upwards from the bottom surface of the intake reservoir  410  such that they are no less than 90%, more preferably no less than 95%, or most preferably no less than 99% of the depth of the intake reservoir  410 . Lugs having a height below the specified ranges may produce unfavorable results such as squeaking, sliding of the lugs against the opposing surface, and deformation of the baseboard or insole of the shoe. The lugs  460  are configured to flex in order to allow for partial compression and deformation of the intake reservoir  410  (e.g., from weight transfer to a heel region of the shoe during a wearer&#39;s stride) while preventing complete collapse of the intake reservoir  410  when pressure is applied to it. 
     As shown in  FIGS. 4A-B , the bottom surface of the exhaust reservoir  430  formed in the shank  370  may extend into the cavity  353  of the midsole to a depth, where the depth is the maximum distance between the top and bottom surfaces of the exhaust reservoir  430 . The depth may be within the range of about 0.1 to about 1.0 cm, more preferably about 0.1 to about 0.5 cm, and in a preferred embodiment is about 0.2 cm. The volume of the exhaust reservoir  430  may be within the range of about 2.8 cm 3  to about 28 cm 3 , more preferably about 2.8 cm 3  to about 14 cm 3 , and in a preferred embodiment within about 2.8 cm 3  to about 5.6 cm 3 . A ratio of the volume of the intake reservoir to the volume of the exhaust reservoir may be within a range of about 1.5 to about 3, more preferably about 2 to about 3, and most preferably about 2.5 to about 3. In a preferred embodiment, the exhaust reservoir  430  may in the shape of a half-oval to mimic the contours of the toe of the shoe. However, the shape of the exhaust reservoir  430  is not particularly limited and may be semicircular, circular, square, rectangular, oblong, or otherwise generally polygonal. In some aspects, the exhaust reservoir  430  formed in the top surface of the shank  370  may further include one or more directional flow channels  490  which run in a longitudinal direction from the edge of the exhaust reservoir  430  closest to the heel of the shoe  100  to the edge of the exhaust reservoir  430  closest to the toe of the shoe  100 . These channels  490  are designed to provide for substantially one-way air flow in a direction from the intake reservoir to the exhaust reservoir. In some embodiments, the exhaust reservoir  430  may include one or more lugs  460  which extend upwards from the bottom surface of the exhaust reservoir  430  such that they have a height that is no less than 90%, more preferably no less than 95%, or most preferably no less than 99% of the depth of the exhaust reservoir  430 . Lugs having a height below the specified ranges may produce unfavorable results such as squeaking, sliding of the lugs against the opposing surface, and deformation of the baseboard or insole of the shoe. The lugs  460  are configured to flex in order to allow for partial compression and deformation of the exhaust reservoir  430  (e.g., from weight transfer to a toe region of the shoe during a wearer&#39;s stride) while preventing complete collapse of the exhaust reservoir  430  when pressure is applied to it. 
     As shown in  FIGS. 4A-B , the bottom surface of the connecting channel  450  formed in the top surface of the shank  370  may be positioned within the corresponding cavity  355  running longitudinally through a midfoot section of the midsole  300 . The bottom surface may extend into the cavity  355  of the midsole to a depth, where the depth is the maximum distance between the top and bottom surfaces of the connecting channel  450 . The depth may be within the range of about 0.05 to about 0.5 cm, more preferably about 0.2 to about 0.5 cm, and in a preferred embodiment is about 0.4 cm. The cross sectional area of the connecting channel  450  may be within the range of about 0.02 cm 2  to about 0.1 cm 2 , more preferably about 0.02 cm 2  to about 0.08 cm 2 , and in a preferred embodiment within about 0.02 cm 2  to about 0.04 cm 2 . In a preferred embodiment, a cross sectional shape of the connecting channel  450  is rectangular. However, the cross sectional shape of the connecting channel may be semicircular, circular, square, oblong, or otherwise generally polygonal. In some aspects, the bottom surface of the connecting channel  450  formed in the shank may comprise a directional flow channel  490 . 
     In this embodiment, the baseboard  500  may be disposed on the top surface of the midsole  300  and over the embedded shank  370  such that it forms a top surface for the intake reservoir, exhaust reservoir, and connecting channel. In some aspects, the baseboard may have perforations positioned in a heel region and a toe region in order to allow air flow in and out of the intake and exhaust reservoirs, respectively. 
       FIGS. 5A-B  show another embodiment of the ventilation mechanism  400 . This embodiment provides a ventilation mechanism which generally comprises an intake reservoir  410 , an exhaust reservoir  430 , and a connecting channel  450  formed integrally into the midsole  300 , shank  370 , and baseboard  500  of the shoe. However, the bottom surfaces of an intake reservoir  410 , an exhaust reservoir  430 , and a connecting channel  450  may be formed by depressions in the top surface of the midsole  300  and their top surfaces may be provided by a shank  370 . Thus, the shank  370  may be laid over cavities in the top surface of the midsole  300  such that a hollow intake reservoir  410  may be formed in a heel region of the midsole  300 , a hollow exhaust reservoir  430  may be formed in a toe region of the midsole  300 , and a hollow connecting channel  450  may be formed in a longitudinal region running between the heel and toe regions of the midsole  300 . In some embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. In some aspects, the intake and exhaust reservoirs may include one or more lugs  460  which extend downwards from the top surface provided by the shank  370  and towards the bottom surface provided by the midsole  300  such that they have a height that is no less than 90%, more preferably no less than 95%, or most preferably no less than 99% of the depth of the intake or exhaust reservoir. The shank  370  may be provided with perforations  415 ,  435  in heel and toe regions in order to allow air flow into the intake reservoir and out of the exhaust reservoir, respectively. 
       FIG. 6  shows yet another embodiment of the ventilation mechanism  400 . Such an embodiment provides a ventilation mechanism which is formed integrally into a removable insert  470  which may be provided to a shoe  100 . The removable insert  470  has a bottom surface  471  which is configured to be closest to the outsole  200  when inserted into the cavity of a shoe  100  and a top surface  473  which is configured to be closest to the foot of a wearer. In some embodiments, the removable insert  470  may replace the insole  600 , while in other embodiments, it may be used in addition to the insole  600 . The bottom surface  471  of the removable insert  470  may comprise an intake reservoir  410  in a heel or instep region, an exhaust reservoir  430  in a toe region, and a connecting channel  450  running between the intake and exhaust reservoirs. In some embodiments, the exhaust reservoir may be disposed elsewhere than in the toe region, for example in the heel, in the lining, or in the upper. In an embodiment, the top surfaces of the intake reservoir, exhaust reservoir, and connecting channel may be formed by depressions in the bottom surface  471  of the removable insert  470 . In such an embodiment, a substantially planar cover sheet  475  may be adhered to the bottom surface  471  of the removable insert  470  over the top of the depressions so that it forms a planar bottom surface of the intake  410  and exhaust  430  reservoirs and the connecting channel  450 . 
     As shown in  FIG. 6 , the intake reservoir  410  and exhaust reservoir  430  of this embodiment may have cross sectional areas or diameters that are widened with respect to those of the connecting channel  450 . In some embodiments, the connecting channel  450  may run in a substantially linear route from the intake reservoir  410  to the exhaust reservoir  430 , while in other embodiments, the connecting channel  450  may comprise a more circuitous nonlinear shape. In a preferred embodiment, the connecting channel  450  may comprise a hook or loop configuration which runs substantially parallel to the periphery of the heel region. In the exhaust reservoir, a perforation  415  may be provided which extends all the way through the removable insert so that air may be exhausted from the removable insert  470  and past its top surface. Similarly, the intake reservoir  410  may be designed to connect to or otherwise communicate with air flow channels  1100  formed along the inside surface of the upper  700  in order to draw air from the outside environment. In some embodiments, the connecting channel  450  and/or the exhaust reservoir  430  may comprise directional flow channels  490 . 
     Baseboard 
     As shown in  FIG. 1 , the baseboard  500  may be a substantially planar member having a bottom surface configured to contact the top surfaces of both the midsole  300  and, in a preferred embodiment, the ventilation mechanism  400  and a top surface which is configured to contact the insole  600 . In some embodiments, the baseboard  500  may form a top surface of the intake reservoir  410 , exhaust reservoir  430 , and connecting channel  450 . The baseboard  500  may be permanently secured to the midsole  300  by an adhesive, or alternatively, by stitching or injection molding. In some aspects, the baseboard  500  may have one or more cut-outs  510 ,  530  which are configured to sit over the intake reservoir  410  and the exhaust reservoir  430  in order to facilitate air flow through the ventilation mechanism  400 . These cut-outs may filled with inserts made of a mesh, foam, fabric, or other breathable membrane or, alternatively, may be free from any filler or covering material. The baseboard  500  may be constructed of materials such as PET, polyester, injected nylon, or polyethylene. The baseboard  500  may have a thickness within the range of about 0.1 to about 0.5 cm. 
     Insole 
     As depicted in  FIGS. 7A-B , the insole  600  comprises a flexible insert which has a bottom surface  610  configured to contact the baseboard  500  and a top surface  630  configured to receive the foot of a wearer. In some aspects, the insole  600  may be removable from the shoe. The insole  600  may be primarily formed from a polyurethane material such as polyurethane, EVA, or TPU. 
     In some aspects, the top surface  630  of the insole may be covered by a thin layer of fabric material such as polyester. This fabric layer may be permanently adhered to the insole using an adhesive or the like. In some embodiments, the top surface  630  of the insole may be substantially planar, while in other embodiments, the top surface  630  may include raised portions around the edge of a heel region or along an instep region in order to cradle and provide support for a wearer&#39;s foot. 
     In some embodiments, the ventilation mechanism may be disposed within insole  600 . In some aspects, the ventilation mechanism may be a separate hollow insert which may be housed within cavities disposed within the insole. In other embodiments, the ventilation mechanism may be formed integrally within the material of the insole, such that the material of the insole defines the hollow intake reservoir, the exhaust reservoir, and the connecting channel. In some aspects, the bottom surface  610  of the insole may include an air intake pattern  611  in a heel region and an air exhaust pattern  613  in a toe and forefoot region. The air intake pattern  611  in the heel region may include a depressed or hollowed out area in the center of the heel region which is of a lower elevation than the edges of the heel. The intake pattern  611  may further include one or more channels of similarly lower elevation, cut into the bottom surface  610  of the insole, and running from the depression in the heel area towards the periphery of the insole  600  in the area of the midfoot or the instep. These channels may connect to or communicate with the air flow channels  1100  in the upper  700  to provide an avenue for air flow from the outside environment into the shoe  100  and underneath a heel portion of the insole  600  so that it may be drawn into the intake reservoir  410  of the ventilation mechanism  400 . 
     The air exhaust pattern  613  may be disposed in a toe and forefoot region of the bottom surface  610  of the insole and separated from the air intake pattern  611  by a raised ridge  615 . The air exhaust pattern  613  may include a pattern of raised lugs which may be in the shape of diamonds, circles, squares, rectangles, or other polygons. In a preferred embodiment, these raised lugs are hexagonal in shape. The raised lugs are positioned so that they define a network of depressed channels between their respective edges. Each of the raised lugs includes a slight depression in its center with a perforation that extends entirely through the insole. The raised pattern, depressed channels, and perforations allow for air exhaust flow exiting the ventilation mechanism  400  to flow through a forefoot portion of the shoe  100  beneath the insole  600  before exiting through the perforations in the air exhaust pattern  613  of the insole to contact and cool a wearer&#39;s foot. 
     Upper 
     As shown in  FIGS. 8A-B , the upper  700  extends upwards from the midsole  300  to form a cavity configured to receive a user&#39;s foot. The upper  700  has an inner surface configured to receive a wearer&#39;s foot and promote air flow within the shoe  100  and an outer surface configured to repel water and otherwise interact with the outside environment. The upper  700  may be constructed from one of a number of waterproof membranes, including waterproof leather, silicone seam seal, or a waterproof membrane material with a heat-welded seam seal material. 
     The upper  700  may additionally include a tongue portion  710  and a lacing component  730 . The tongue portion  710  may be configured to be pulled back by a wearer so that a foot may be inserted more easily into the cavity of the shoe  100 . Once the foot is settled within the cavity of the shoe  100 , the tongue  710  may tightened to the foot using the lacing component  730  so that the wearer&#39;s foot fits snugly and securely within the shoe. In some aspects, the tongue portion  710  of the upper  700  may have a raised ventilation channel  711  running longitudinally from a toe portion of the upper  700  to the edge of the shoe cavity. Ventilation channel  711  may be held away from the foot, even when the lacing component  730  is tightened, to allow for air flow up and out of the shoe. 
     Protective Toe Cap 
       FIGS. 9A-B  depict various views of a protective toe cap  800 , in accordance with an embodiment of the invention. The protective toe cap  800  is shaped to fully cover a user&#39;s toes and provide protection therefor. Thus, the protective toe cap  800  is shaped as a hemi-dome in some embodiments. The protective toe cap  800  includes an open underside sized to accommodate a user&#39;s toes, and has a protrusion forming a ventilation channel  810  running longitudinally along the underside. Although a single protrusion is shown, multiple protrusions forming multiple ventilation channels  810  are equally possible and contemplated by the present invention. 
     The protrusion of  FIGS. 9A-B  extends from a midfoot edge of the protective toe cap  800  towards a forefoot edge of the protective toe cap  800  and tapers in the direction of the forefoot edge. As such, a height of the ventilation channel is at a maximum at the midfoot edge of the toe cap  800  and progressively decreases in the direction of forefoot edge until the ventilation channel  810  disappears along the underside of the toe cap  800 . In an embodiment, the lateral cross sectional area of the ventilation channel  810  is shaped as a quadrangle, although it could be semi-circular, triangular, hexagonal, pentagonal, polygonal, or any other shape that adequately provides a ventilation channel. In some embodiments, the ventilation channel  810  may be shaped to engage with the corresponding ventilation channel  711  of the tongue portion of the upper in order to provide a continuous channel from the toe of the shoe  100  to the edge of the cavity of the upper  700 . 
     The protective toe cap is  800 , in an embodiment, composed of a metal or metal alloy material (e.g., titanium) or any other material of a sufficient strength to satisfy safety standards for protective footwear, such as ASTM F2413-11. 
     Ankle Pads 
     As depicted in  FIG. 1 , the ankle pads  900  comprise raised pads permanently affixed to the inner surface of the upper  700  on laterally opposing sides of the shoe  100 . In some embodiments, the positioning of the ankle pads  900  may be substantially symmetrical, but in a preferred embodiment is asymmetrical. The ankle pads  900  may be circular, oval, triangular, diamond, square, rectangular, or otherwise polygonal in shape. The ankle pads  900  are designed to extend from the upper  700  to cause the lining  1000  to protrude and contact the foot and ankle of the wearer. These protruding contact points work to hold the upper  700  off the wearer&#39;s foot in adjacent regions in order to create channels  1100  for air flow from the outside environment into the shoe  100 . In a preferred embodiment, the shape of the ankle pads  900  is selected to contact the ankle of a wearer in anatomical positions which are free of major blood vessels, thereby creating air flow channels  1100  in the adjacent areas where such blood vessels are located. This helps to enhance cooling of the foot and also to prevent vascular constriction and encourage circulation to the foot of a wearer. 
     The ankle pads  900  may be constructed from materials such as open-cell PU, TPU, EVA, or neoprene, and affixed to the upper by stitching, adhesives, high frequency welding or injected directly to the upper. 
     Lining 
     As shown in  FIGS. 1 and 10 , the lining  1000  comprises a porous fabric lining which is disposed on the inner surface of the upper  700 , overtop of the protective toe cap  800  and the ankle pads  900 , such that it covers both of these elements as well as the entire inner surface of the upper  700 . The lining  1000  is permanently secured in position by stitching to the upper  700 . 
     The lining  1000  may be constructed from materials such as polyester or knit nylon. The material of the lining is porous and conducive to air flow, as well as efficient for wicking moisture away from the foot of a wearer. 
     Airflow Channels 
     As shown in  FIG. 1 , in some aspects, the ankle pads  900 , lining  1000 , and ventilation channels  810 ,  711  of the protective toe cap and the upper are positioned to define airflow channels  1100  which are held away from close contact with the foot and ankle of a wearer so as to allow intake and exhaust of air from and to the outside environment. 
     In particular, an airflow channel  1100  to allow exhaust of air from the ventilation mechanism  400  may be formed by the ventilation channels  810 ,  711  in the protective toe cap  800  and the tongue portion  710  of the upper  700 . Airflow channels  1100  to allow intake of air may be formed in the areas adjacent to the ankle pads  900  and in some embodiments, may direct air from the outside environment into the hollowed portion of the intake pattern  611  on the bottom surface of the insole  600  to allow outside air to be draw into the intake reservoir  410  of the ventilation mechanism  400 . 
     Pump-Ventilation of Shoe 
     The various aspects of the present technology function cohesively to provide a continuous flow of outside air through the shoe in a direction from the intake reservoir to the exhaust reservoir. In a preferred embodiment, this direction is a heel-to-toe direction. In such an embodiment, when a wearer begins a stride by transferring weight to the heel of the foot, the intake reservoir  410  is compressed by the downward pressure of a user&#39;s foot and the upwards pressure provided by raised platform  212  of the outsole  200 , causing the air inside to be expelled through the connecting channel  450  and into the directional flow channels  490  of the exhaust reservoir  430 . Because the air flow is in the heel-to-toe direction generally permitted by the directional flow channels  490 , the air easily passes through the channels  490  and is expelled out of the exhaust reservoir  430  through the perforations  435  at the end of the channels  490 . The expelled air then flows through the cut-out  530  provided in the baseboard  500  for this purpose and through the exhaust pattern  613  and perforations in the insole  600 . After the air passes through the perforations of the insole  600 , it may travel upwards through the corresponding ventilation channels  810 ,  711  in the protective toe cap  800  and the tongue  710  before being finally expelled into the outside environment. 
     As the stride progresses, the wearer will transfer weight from the heel of the foot through the midfoot and the toe. As the pressure on the intake reservoir  410  is relieved, the intake reservoir  410  may expand to its original volume, causing it to draw air in through the perforations  415  on its surface. Because the directional flow channels  490  facilitate air flow in a heel-to-toe direction and inhibit air flow in a toe-to-heel direction, the intake reservoir  410  will be refilled primarily from air entering the perforations  415  in the intake reservoir  410  rather than from air flowing into the perforations  435  in the exhaust reservoir  430 . Thus, the intake reservoir  410  draws in air present beneath a heel region of the insole  600 . The intake pattern  611  of the insole  600  assists with channeling air from the airflow channels  1100  of the upper  700  to bottom surface of the insole  600 , and thereby a substantially continuous flow of air from the outside environment is provided to the intake reservoir  410  of the shoe. In this manner, the present technology provides for generally continuous, one-way air circulation through the shoe. 
     EXAMPLES 
     Example 1 
     In order to measure the cooling effect of the present technology during use by a wearer, a conventional waterproof boot (“WP membrane boot”) was compared to a ventilated boot (“HVAC boot”). The conventional boot was constructed of a standard waterproof membrane upper and did not include a ventilation mechanism or airflow channels. The ventilated boot included aspects of a preferred embodiment of the present technology including a ventilation mechanism and airflow channels. To test the boots, a wearer placed a conventional boot on his left foot and a ventilated boot on his right foot and walked on a treadmill at a pace of 3.5 mph for a period of 30 minutes. The temperature of the wearer&#39;s right and left feet were measured every 10 minutes by infrared camera. The results are shown in  FIG. 11 . 
     Example 2 
     The conventional boot was compared to the ventilated boot using the same method as in Example 1, except that, rather than walking on a treadmill, the wearer conducted normal daily activities over the course of 6 hours with temperature measurements taken from inside each boot every hour. The results are show in  FIG. 12 . 
     Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.