CA2931635C - A shoe dryer insert - Google Patents

Abstract

This invention relates generally to a shoe dryer insert in the form of an insert which when inserted into the foot cavity of the shoe draws moisture from the fabric and insulation inside the shoe for the purpose of drying the interior of the shoe. The invention is in the field of devices and methods for drying wet shoes. In the present invention a shoe dryer is arranged to insert into the foot cavity of a shoe and dry the shoe from the inside out, comprising a drying material which holds moisture and a container to hold the material, wherein Voronoi spaces are formed in the container, the spaces arranged along the container in a Voronoi pattern.

Description

A SHOE DRYER INSERT
Field of the Invention The invention is in the field of devices and methods for drying wet shoes.
More particularly, the invention relates generally to a shoe dryer insert in the form of an insert which when inserted into the foot cavity of a boot or shoe draws moisture from the fabric and insulation inside the shoe for the purpose of drying the interior of the shoe.
Background An unwanted consequence of hiking, skiing, running and other physical activities where boots or shoes are worn is that the fabric and insulation inside shoes gets wet from perspiration and from wet and snowy ground.
Typically, wet shoes are simply left to dry in a warm drying room. However, the foot cavity inside the shoe tends to take longer to dry out and so may not always be dry before the next time it is worn.
Prior Art There have been attempts to use artificial means to dry out shoes quickly. For example, the shoes may be placed on a hot radiator or beside a fireplace with a burning fire if one is available.
However, placing shoes on a radiator in home living quarters is unsightly.
Many homes do not have radiators or fireplaces. Shoes often get wet during summer activities when people do not operate their home heaters.
A device that can be inserted into a shoe so as to dry the interior without the aid of a heater was revealed in publication WO-A-I -2008119062 (Grieve et al).
A device for drying footwear or gloves comprises a permeable fabric tube sealed at each end that contains a water absorbing drying agent was revealed in GB-A-(Swanson and Christopher).
A device comprising a weighted body housing soap; wherein the body is designed to assist washing shoes is revealed in US 5230115 (Hollister and Petty).
A fragrance device is disclosed on the internet by Boot Bananas. However, the 'boot banana' doubles as device for drying and imparting a pleasant smelling perfume to the boots, rather than being fully directed to drying efficiency.
A device for inserting into a shoe to make the shoes smell nice is revealed by a product advertised as `dryzone'. However, the device is insufficiently rigid to be easily inserted into a boot and a portion of the device often remains in contact with the wet shoe wall which prevents air circulation and thereby impedes drying.
The products revealed by the prior art suffer from several deficiencies. For example, they do not promote passive airflow over the material to be dried. Many products include fabric which is in contact with the moisture in the shoe which in turn means that the fabric degrades over time. The products in the prior art were not always easy to insert into the shoe because of the friction of fabric. Generally, they cannot dry the whole shoe efficiently or stand up to repeated robust use.
The present invention was devised in order to overcome the aforementioned and other drawbacks of existing products.
Summary of the Invention According to an aspect of the present invention there is a shoe dryer arranged to insert into a foot cavity of a shoe and dry the shoe from the inside out, comprising a foot shaped container having a toe and ankle to insert into the foot cavity so as to remove moisture from the inside of the shoe, the container comprising a lattice extending from toe to ankle, a Voronoi pattern of apertures is formed in a wall of the container to provide passageways for air.
Preferably the container is shaped to substantially fill the interior volume of a shoe from toe to ankle opening. Advantageously the container holds the foot cavity of the shoe

- 2 -Date recue/Date received 2023-02-10 open. The container also holds the ankle opening of the shoe open. Hence the shoe dryer provides access for air to circulate from outside the shoe into the shoe and then back out of the shoe. The circulating air dries the fabric and insulation inside the shoe.
Preferably the container is rigid. Advantageously the container is easy to insert into the foot cavity and to remove from the shoe.
Preferably the container has a substantially right angle proximate a heel intermediate the toe and ankle. Advantageously in use the container extends from the ankle opening of a shoe to the toe of the shoe. Advantageously the container fits loosely in the foot cavity of the show because both the foot cavity and the container have substantially the same ninety-degree bend proximate a heel region.
Preferably the container is perforated by the spaces arranged in a Voronoi pattern which are also known as Voronoi spaces. Advantageously moist air wafts through the Voronoi spaces and comes into contact with a drying material contained inside the container.
Preferably the lattice forms a hollow interior of the container to contain the drying material which improves removal of moisture from the air inside the shoe.
Advantageously the drying material is contained within the hollow interior of the shoe dryer and is exposed to the air inside the shoe and dries the air which in turn draws moisture from the fabric and insulation inside the shoe.
Advantageously the spaces are distributed along the container from the toe end to the ankle end so that drying material is evenly distributed throughout the foot cavity of the shoe from the ankle opening to the toe.
Preferably the container comprises an opening proximate the ankle.
Advantageously drying material may be delivered through the opening into the container and drying material may be delivered through the opening of the container so as to load and unload the container with the drying material.
Preferably the container is a hollow shell which in use has an opening at an end proximate the ankle opening of the shoe, the opening being arranged to receive the drying material. Advantageously a sock or cage is provided, the sock or cage

3 conforming to the interior of the shell, in which drying material is housed.
Ideally the drying material is in the form of loose granules, beads or particulate material and is held in position inside the shell so as to distribute the drying material from the toe end to the ankle end of the container.
Preferably the shoe dryer comprises a rigid cage which inserts through the opening in the container and holds the drying material. The cage is permeable to water and airborne moisture. Advantageously the cage is easily placed in position and held inside the container.
Preferably the container is formed from two halves, joined along a surface of .. separation, extending from the end of the container, which in use is closest to the toe of the shoe, to the end of the container closest to the ankle opening.
Advantageously one of the one of the halves may comprise the lattice defining the spaces in the Voronoi pattern and the other half may be a smooth surface to aid insertion into the sock. Advantageously the both halves may comprise the lattice for air flow through the container.
Preferably the two halves are separable and able to be rejoined along the surface of separation to load the drying material into the container and unload the drying material from the container. Advantageously drying material may be delivered into the container and drying material may be delivered out of the container when the two halves are separated. The two halves may be joined one to another with the drying material inside the container.
Preferably the shoe dryer comprises a sock which holds the drying material, wherein the sock is made of a sacking permeable to water and air-borne moisture.
Advantageously the container is rigid and supports the sock and holds the sock apart .. from the wet fabric and insulation of the interior of the boot.
Preferably the shoe dryer comprises a sock to hold granular drying material to remove moisture from the air inside the shoe; the sock being of sufficient length to extend from toe to ankle of the container and being permeable to water and air borne moisture.
Preferably the sock has a shape that when substantially full of drying material, conforms to the interior of the container shell and inserts into and is held within the container.

4 Preferably the shoe dryer comprises a plurality of such socks.
Preferably the sock comprises an outer layer comprising a mesh permeable to water and airborne moisture. The mesh allows air in the shoe cavity access to the drying material in the sock. Advantageously the drying material drying the air inside shoe and the air in turn dries the fabric and insulation inside the shoe.
Preferably the sock comprises a lining joined to the inside of the outer layer whereby intermediate the lining and outer layer there is formed a compartment to contain the granular drying material. The compartment is a pouch and may be refillable with drying material. Preferably the lining covers the inside of the sock from toe to ankle opening. Preferably the pouch formed by the lining and outer layer of the sock is arranged from toe to ankle opening. Advantageously the drying material inside the pouch is held in the pouch proximate the toe and along the length of the sock to the ankle opening. The fabric and insulation inside the shoe is thereby dried from the toe to the ankle opening.
Preferably the shoe dryer comprises a rigid former to insert into and support the sock from toe to ankle of the container. Advantageously when the rigid former is inserted in the sock and there is drying material in the pouch, the rigid former supports the sock and thereby the granular drying material in the pouch from toe to ankle within the container.
Preferably the rigid former is moulded from polymeric material. Preferably the rigid former has a smooth surface to aid insertion into the sock.
Preferably the rigid former comprises a lattice extending from toe to ankle defining a Voronoi pattern of spaces through the rigid former to provide a passageway for the air.
Advantageously when the rigid former is in the sock, the spaces through the rigid former provide a passage for air to the drying material in the pouch. So the drying material has access to air that passes though the spaces arranged in a Voronoi pattern in the rigid former. The drying material also has access to air that passes through the spaces arranged in a Voronoi pattern in the container. The advantageous combination of the container with spaces and rigid former with spaces assists drying the shoe from the inside out.
Advantageously the spaces arranged in Voronoi pattern provides for plenty of open

5 space between the lattice for moist air to waft through and read the drying material.
The meaning of width is substantially the same as the diameter of the container.
Preferably the shape of the Voronoi spaces is determined by virtual seed points spaced along the container, and for each seed point there is a corresponding Voronoi space consisting of all points closer to the that seed point than any other.
Preferably the container comprises a lattice framework, wherein the Voronoi spaces are spaces formed by the lattice framework. Advantageously the container comprising the lattice work is easily formed by moulding.
Voronoi patterns are found in nature, for example on giraffe animal skins.
A Voronoi pattern defines the largest area for empty spaces defined by enclosing polygons amid a set of points on a surface.
The shoe dryer has a container with a surface on which there are seed points for a Voronoi pattern. The Voronoi pattern thereby defines the lattice which forms the hollow interior of the container. Ventilation is provided by the spaces so that air travels with very low impediment from wet fabric of a boot or shoe lining outside the container to a drying medium inside the container. This is because the Voronoi pattern forms large empty spaces in the lattice for air to pass through and relatively small walls of the lattice which provide relatively little impedance to air compare to other types of lattice. Experimental results provided below demonstrate that the lattice work defined by a Voronoi pattern is effective for drying.
In use the container defined by the lattice and containing the drying medium is shoved into wet boot and jerked out of a dry boot The container is routinely subject to rough treatment including being tossed about in a boot. Consequently, the lattice must be strong and able to take repeated stresses without breaking while still providing excellent ventilation. Using only the prior art, the lattice could be strengthened by making the lattice walls thicker. However, making the lattice walls thicker has the effect of making the spaces defined by the lattice relatively smaller which would reduce the ventilation capability of the lattice.
A characteristic of the Voronoi pattern which is evident from a giraffe skin is that it avoids small angles in order to define the largest empty enclosing polygons.
Hence the lattice around the seed points on the container has mostly large angles.
By

6 avoiding small angles of less than preferably fifteen degrees, and more preferably less than forty degrees, and more preferably less than sixty degrees, weakness of the lattice is also avoided. Small angles lead to corners with high stress concentrations where cracks would form in the lattice when the container is repeatedly shoved roughly into the boot and yanked out of the boot.
The lattice defined by a Voronoi pattern which has polygons defined by relatively large angles is relatively strong. The large angles of the lattice make for relatively low stresses at the corners of the lattice. Hence the container defined by the lattice able withstand repeated use without cracks forming in the corners.
The lattice defined by the Voronoi pattern provides large spaces for ventilation and large angles for high strength. The shoe dryer which comprises a container defined by the lattice provides efficient ventilation between wet walls of a boot and a drying medium inside the container while being rugged enough to be inserted and removed roughly from work and ski boots. The lattice with the Voronoi pattern provides the container with a favourable ratio of ventilation efficiency to practical rough abuse strength.
The Voronoi pattern also facilitates provision of a favorable ratio of open space in the lattice to wall thickness of the lattice because the large angles of the lattice mean the lattice walls do not have to be very thick for the container to have rugged strength.
Preferably the shoe dryer is formed of material with a melting temperature above 220 degrees centigrade. Advantageously the shoe dryer may be heated with drying material contained in the container. Heating the drying material releases the moisture it has captures so that the shoe dryer may be re-used.
Preferably the container is arranged to receive a conduit for forced air.
Advantageously air is forced through the Voronoi pattern of open spaces so as to circulate air inside a shoe or boot so that the forced air, which is ideally warm, speeds up removal of moisture from wet walls of the shoe or boot. Preferably the Voronoi pattern of open spaces forms air outlets for the forced air conduit.
According to another aspect of the invention there is a system comprising a plurality of shoe dryer inserts herein described, supported on a network of ducts or pipes which deliver forced air from a pump for drying a plurality of boot and shoes.

7 Preferably the shoe dryer inserts are fixed to a hollow tubular structure which is in the form of hollow tubes arranged as a rack such that the boots and shoes may be placed upside down on the shoe dryer inserts with the containers inside the shoes and boots.
Preferably the shoe dryer inserts are arranged in rows on the structure so that the shoes and boots may be hung in rows. Preferably a heater heats the air prior to being forced through the Voronoi pattern of open spaces. The heater may recover heat from buildings and use other sources of waste or low grade heat in order to heat a flow of forced air.
According to another aspect of the invention there is provided a kit of parts comprising the dryer insert herein described, and a package of loose drying medium to be contained in the container. Preferably the kit also comprises a sock for holding the drying medium as herein described. Preferably the kit includes the loose drying medium contained in the sock.
Advantageously the container is effective for providing air circulation from a drying medium in the container to wet walls of a hollow vessel into which the container is inserted, and thereby accelerating drying of the wet walls of the vessel.
Hence the shoe dryer insert herein described has general utility for drying walls of a hollow vessel.
Preferably the lattice comprises an embedded resistance heater suitable for heating the lattice and drying material contained in the container to release moisture captured by the drying material.
Preferably the shoe dryer comprises the drying material to remove moisture from the air inside the shoe.
Preferably the lattice framework comprises an embedded resistance heater suitable for heating the drying material in the Voronoi spaces to a sufficient temperature to dissociate moisture attached by adsorption to the drying material.
Advantageously the shoe dryer is quickly regenerated for drying more wet shoes.
Preferably the container is formed using non-electrically conductive materials such glass, ceramic or microwave safe plastic with a high melting temperature, whereby the drying material in the Voronoi spaces can be heated to a sufficient temperature in a microwave oven to dissociate moisture attached by adsorption to the drying material.

8 The invention will now be described, by way of example only, with reference to the accompanying drawings in which:
Brief Description of the Figures Figure 1 is a side view of a shoe dryer insert according to the invention;
Figure 2 is an exploded view of the shoe dryer shown in Figure 1; and Figure 3 is a side view of a rigid former to insert into a sock containing drying material and contained in container of a shoe dryer according to the invention.
Detailed Description of the Invention Referring to the Figures, there is shown in Figure 1 a side view of the shoe dryer 100.
The shoe dryer shown in Figure 1 is particularly suitable for a boot with a long ankle portion. Although not shown, the shoe dryer is also appropriate with a shorter ankle length suitable for a shoe.
As shown in Figure 2, the first embodiment of the shoe dryer comprises a container 10, that is a hollow shell comprising a lattice.
In Figure 2 the container 10, 20 is shown as comprising two separable halves.
It is not necessary for the container 10, 20 to be comprised of two halves. The container 10, 20 can be a single shell.
20 There are spaces 13, 23 arranged along the container in a Voronoi pattern. The Voronoi pattern is a partitioning of the surface of the container 10, 20 into regions based on distance to points in a specific subset of the surface. That set of points (called seeds, sites, or generators) is preselected to so that spaces aid the drying effect of the new dryer insert. For each seed there is a corresponding region of the container 10, 20 consisting of all points closer to that seed than to any other. These regions are the Voronoi spaces.
In the arrangement of Voronoi spaces, every point within a given Voronoi space is

9 closer to the "seed" inside that space than it is to any other point in a neighboring Voronoi space.
The container 10, 20 comprises a lattice 14, 24. The spaces intermediate the lattice are the Voronoi spaces 13, 23.
In Figure 1 and Figure 2 the container 10, 20 is shown perforated by the Voronoi spaces 13, 23. The shoe dryer 100 is placed into the cavity of a shoe. Then air carrying moisture from the wet fabric and insulation inside the shoe wafts through the Voronoi spaces 13, 23.
Figure 2 shows that inside the shell of the container 10, 20 is held a sock or a cage 30.
The sock or cage 30 holds drying material with takes up moisture from the air that wafts through the Voronoi spaces 13, 23.
Moisture captured from air by the drying material is removable by heating the material.
Silica gel will lose its chemically bound water and hygroscopic properties if heated.
There are indicator gels, incorporating organic dyes that are heat sensitive and their color indicating dye will indicate the silica gel is dried when heated above 125-150 C.
Indicating silica gel be heated to about 120 C and regular gel be heated about to drive off the moisture. The principle impact of a lower heat of regeneration is that a longer time is required to dry the gel and there is less potential for the degradation of silica gel properties.
In a conventional oven, the time of regeneration varies from minutes to hours, depending on temperature and the thickness of the gel. Although silica gel can be dried in a microwave oven, it is difficult to determine the temperature inside the gel. Also, since metal cannot be used in a microwave oven, only glass, ceramic or microwave safe plastic with a high melting temperature should be used to fabricate the shoe dryer.
Figure 2 shows that the container 10, 20 comprises two half shells which are separable. The sock or cage 30 contains drying material in the form of loose stuff beads, granules, or sandy material. With the two half shells of the container apart 10, 20, the sock or cage 30 is easily placed in position where the two half shells of the container are clamped around the sock or cage 30 thereby holding the drying material securely within the container 10, 20.

The two half shells of the container 10, 20 are clamped together by a disconnectable connector 15, 25 at the toe end of the container and by a disconnectable connector 16, 26 at the ankle end of the container. The two half shells may be clamped together by connecting them together at the toe end of the container with connector 15, 25 and by connecting them together at the ankle end of the container with connected 16, 26.
The two half shells may be unclamped by disconnecting the connector 15, 25 and the connector 16, 26. Each half shell comprises a corresponding portion of the connector 15, 25 and the connector 16, 26.
The two halves of the container 10, 20 are joined along a surface of separation 21 extending from the end of the container which in use is closest to the toe of the shoe to the end of the container closest to the ankle opening.
A modification of the first embodiment is for the container 10, 20 to not be two separable parts. In the modification the container is a hollow shell with a lattice forming the arrangement of Voronoi spaces. The end 15 of the container 10, 20 that in use is closest to the ankle opening is an open end. To place the drying material in the container 10, 20 the sock or cage 30 is inserted through the open end 15 of the container.
The drying material is just as easily removed from container by reversing the procedure by which it is placed inside the container.
The container 10, 20 is formed of rigid material so the container 10, 20 is easily inserted into a shoe though the ankle opening into the foot cavity of the shoe. The sock 30 which contains the drying material is floppy. The sock comprising drying material is easily inserted into the foot cavity of the shoe because the sock is contained inside the rigid container.
The container 10, 20 touches the wet fabric inside the shoe, but the sock does not so the sock does not degrade as quickly as it would if it were in direct contact with the wet fabric of the shoe.
The container prevents the sock from getting soaked by direct contact with fabric and insulation inside the shoe. Moist air breathes through a dry sock better than it breathes through a wet sock. The drying material inside the sock thereby gets the moist air efficiently through a dry sock.

The sock is supported inside the container 10, 20 by the lattice 14. The drying material in the sock is held in the shoe from the toe to the ankle opening thereby helping to efficiently dry the fabric and insulation inside the shoe from the ankle to the toe.
The shoe dryer 100 also comprises a rigid former 40, 200 to insert into and support the sock 30. The rigid former is elongate with a curve that is substantially ninety degrees.
When the rigid former 40, 200 supporting a sock 30 is in the container 10, 20 and container is in the foot cavity of a shoe, the container, the rigid former, and the sock extend from toe to ankle opening of the foot cavity. The toe end 205 of the container is proximate the toe of the shoe and the ankle end 206 of the container is proximate the ankle end of the shoe.
In Figure 3 the rigid former insert 200 is shown comprising a lattice 204 and the Voronoi spaces 203 are formed by the lattice. The Voronoi spaces are arranged along container from the ankle end to the toe end.
The rigid former 40 has a smooth surface embodiment shown in Figure 2. The rigid former 200 also has an embodiment comprising a lattice defining spaces 203 through the rigid former arranged in a Voronoi pattern. The Voronoi spaces are shown in Figure 3 as perforations through the rigid former 200.
Alternatively, the drying material is moulded into place in the Voronoi spaces.
Alternatively, the drying material is placed into socks cages which conform to the shape of the spaces and the socks or cages placed in the Voronoi spaces.
The effectiveness of the shoe dryer 100 is by the results of testing which are given below.
The tests demonstrated the amount of time for a ski boot to dry on its own was compared to the amount of time it took the same wet ski boot to dry with the shoe dryer actually inserted into the ski boot.
In the tests the interior fabric and insulation of a ski boot was dampened with 284 ml of water and left overnight in a room. The toe region was dampened more than the ankle region to mimic how perspiration from the foot dampens the boot.

The relative humidity and temperature in the room was recorded before and after each test. For each test, the temperature and relative humidity were kept similar.
Readings were taken at the beginning and end of each test. Readings were the taken at the toe of the boot. Readings were also taken at ankle level. The reading taken included the temperature and relative humidity in the testing chamber at the beginning of the test. The readings also included the temperature and relative humidity in the testing chamber at the finish of the test.
The readings included a relative moisture measurement of the dampened fabric in the toe region. The readings included a relative moisture measurement of the dampened fabric at the ankle region. The scale for the relative moisture measurement ranged from zero moisture units to one hundred moisture units. A reading of zero moisture units would have indicated that the cloth was completely free of moisture. A
reading of one hundred moisture units would have indicated that the cloth was soaked with water.
Twelve tests were carried out. The five tests were carried out on ski boots left to dry in the same chamber. These five tests were:
first set of tests - a set of control tests to dry a ski boot without aid of any drying device and the opening of the boot uncovered;
second set of tests - a set of tests to dry a ski boot with a shoe dryer 100 comprising a container 10, 20, a sock 30 holding drying material, a smooth rigid former 40 inside the sock and supporting the sock, and the shoe dryer 100 inserted and the opening of the boot uncovered;
third set of tests - a set of tests to dry a ski boot with a shoe dryer 100 comprising a container 10, 20, a sock 30 holding drying material, a smooth rigid former 40 inside the sock and supporting the sock, and the shoe dryer 100 inserted and the opening of the boot covered;
fourth set of tests - a set of tests to dry a ski boot with a shoe dryer 100 comprising a container 10, 20, a sock 30 holding drying material, a rigid former 200 inside the sock and supporting the sock wherein the rigid former 200 comprises a lattice 204 defining spaces 203 through the rigid former arranged in a Voronoi pattern, and the shoe dryer 100 inserted and the opening of the boot uncovered; and fifth set of tests - a set of tests to dry a ski boot with a shoe dryer 100 comprising a container 10, 20, a sock 30 holding drying material, a rigid former 200 inside the sock and supporting the sock wherein the rigid former 200 comprises a lattice 204 defining spaces 203 through the rigid former arrange in a Voronoi pattern, and the shoe dryer 100 inserted and the opening of the boot covered.
Each set of tests consisted of the same test repeated three times so that there are three tests in each set of tests and three set of test result in each set of tests. There is an individual table of results presented for each table.
The first set of tests were 'control' tests. The three control tests were carried out to determine at what rate the boot would dry by normal means of evaporation. The control tests were drying tests of a typically damp ski boot simply left to dry in still air.
A shoe dryer was not used in the control tests. In the control tests the ski boot was left to dry in air without any drying aid.
Table 1 shows the results and measurements of the three control tests.
The start temperature of the three control tests differed by less than one degree Celsius, and the end temperature differed by only a maximum of 3.4 degrees Celsius.
The relative humidity at the start of the three tests differed by a maximum of about ten percent. The relative humidity at the end of the three tests differed by a maximum of about five percent.
The three control tests demonstrated that the ski boot in the toe region only dried by a maximum of four moisture units over the period from the beginning of the test to the end of the test.
The three control tests demonstrated that the angle region of the ski boot only dried by a maximum of seven moisture units over the period from the beginning of the test to the end of the test.
The three control tests showed that without any drying aid the toe region dried by an average of four moisture units over the length of the test and the ankle region dried by an average of 3.7 moisture units.

In all tests to dry the ski boot using the shoe dryer, the readings taken were exactly as for the control tests described above. Readings were taken in the toe region and readings were taken in the ankle region of the boot.
In the second set of three tests the ski boot was foot opening was not covered. The shoe dryer 100 shown in Figures 1 and 2 was simply inserted into the ski boot and then the ski boot was left to dry.
Air carrying moisture from the damp fabric and insulation from the boot wafts through the Voronoi spaces formed by the lattice of the shell form container. The air carrying moisture passes thought the cage or sock and the moisture in the air is then captured by adsorption into the drying material in the sock.
Table 2 shows the results and measurements of a second set of three tests.
With the shoe dryer actually inserted into the boot, the moisture content in the toe region of the boot was reduced by an average of thirty-nine percent over the course of the test. In the ankle region the moisture content at the ankle region was approximately thirty-nine percent.
The drying effect of the shoe dryer illustrated in Figures 1 and 2 is clear from Table 2.
The control tests result shown in Table 1 showed that without the shoe dryer inside the shoe, the fabric at the toe only dried enough to lose an average of four moisture units.
The second set of three tests showed that with the first embodiment of the shoe dryer inside the ski boot the fabric at the toe dried over the duration of the test by an average of 39.3 moisture units. The maximum that the fabric at the toe dried was forty moisture units, and the least the fabric at the shoe dried was thirty-nine moisture units.
The control tests showed that without the first embodiment of the shoe dryer inside the shoe, the fabric at the ankle only dried enough to lose an average of 3.7 moisture units.
The second set of three tests showed that with the shoe dryer inside the ski boot the fabric at the ankle dried over the duration of the test by an average of 38.7 moisture units. The most the fabric at the toe dried was forty-one moisture units, and the least the fabric at the shoe dried was thirty-eight moisture units. The second set showed the new shoe dryer works with reassuring consistency.
The second set of tests showed that the average percentage of the moisture absorbed was 421 percent at the toe and 47.6 percent at the ankle.
Inspection of the silica beads in the shoe dryer immediately after the second set of tests showed that the beads were not saturated with moisture.
In the third set of three tests the ski boot foot opening was covered. The shoe dryer was simply inserted into the ski boot, the foot opening was covered and then the ski boot was left to dry.
In the third set tests an identical shoe dryer insert to the one for the second set of tests was used.
The temperature and humidity in the room at the beginning of the three tests at the end of the third set of tests was nearly the same as the temperature and humidity at the start of the control tests and the second set of tests.
The moisture content in the fabric and insulation of the ski boot in the toe region and in the ankle region at the beginning of the third set of tests was also similar to the moisture content in the fabric and insulation of the ski boot in the toe region and in the ankle region of the ski boot in the control and second set of tests.
Table 3 shows the results of the third set of tests.
As shown in Table 3, the fabric and insulation in the toe region dried a minimum of twenty-six moisture units and a maximum of forty-two moisture units. The average number of moisture units dried was 33.3. This is about six moisture units less than when the shoe opening was uncovered. Covering the boot hampers drying in the toe region when a shoe dryer is used.
The fabric and insulation in the toe region dried a minimum of twenty-eight moisture units and a maximum of forty-two moisture units. The average number of moisture units dried was 35.3. This is about three moisture units less than when the shoe opening was uncovered. Covering the boot hampers drying in the ankle region when a shoe dryer is used.
However, compared to simply allowing the boot to dry in air without any drying aid, the shoe dryer is effective at drying the toe and ankle region of the boot even when the boot opening is covered because without any drying aid the toe and ankle regions only dry by about four moisture units over the test period.
In the fourth set of tests the shoe dryer comprises a rigid former 200 comprising spaces arranged in Voronoi pattern shown in Figure 3. Moist air wafts past the beads or granules as passes through the Voronoi spaces in the container 10, 20 and through the Voronoi spaces 203 in the rigid former 200. The Voronoi spaces effectively present a large surface area of drying material packed in them to the air in the boot, while also providing nooks to hold the drying material in the container.
The temperature and humidity in the room at the beginning of the fourth set of three tests and at the end of the fourth set of tests was nearly the same as the temperature and humidity at the start of the control set of tests, and the second and third set of tests.
The moisture content in the fabric and insulation of the ski boot in the toe region and in the ankle region at the beginning of the third set of tests was also similar to the moisture content at the beginning of the control, second, and third set of tests.
Table 4 shows the results of the fourth set of tests.
As shown in Table 4, the fabric and insulation in the toe region dried a minimum of thirty-one moisture units and a maximum of 42 moisture units. The average number of moisture units dried in the toe region was 37.6. By comparison, the toe region only dried an average of four moisture units during the control set of tests when no drying aid was used. These results confirm that the second embodiment of the shoe dryer dries the toe region of the ski boot.
Table 4 also shows that the fabric and insulation in the ankle region dried a minimum of twenty-three moisture units and a maximum of 51 moisture units. The average number of moisture units dried in the ankle region was thirty-three. By comparison, the ankle region only dried an average of 3.7 moisture units during the control set of tests when no drying aid was used. These results confirm that the second embodiment of the shoe dryer dries the ankle region of the ski boot.
Table 5 shows the results of the fifth set of tests. In these tests the ankle opening of the shoe is covered. The fabric and insulation in the toe region dried a minimum of twenty-five moisture units and a maximum of thirty-seven moisture units. The average number of moisture units dried in the toe region was 32.3. By comparison, the toe region only dried an average of four moisture units during the control set of tests when no drying aid was used. These results confirm that the shoe dryer comprising the rigid former comprising a lattice with defining Voronoi spaces dries the toe region of the ski boot when the ankle opening is covered.
Table 5 also shows that the fabric and insulation in the ankle region dried a minimum of nineteen moisture units and a maximum of 38 moisture units. The average number of moisture units dried in the ankle region was thirty. By comparison, the ankle region only dried an average of 3.7 moisture units during the control set of tests when no drying aid was used. These results confirm that the second embodiment of the shoe dryer dries the ankle region of the ski boot, but not as much as if the ankle opening of the ski boot is uncovered.

Table 1. Control Tests Test 1 Test 2 Test 3 Temperature at start of test (Celsius) 20.9 20.9 19.4 Relative Humidity at start of test (% RH) 48.5 40.6 51.4 Temperature at end of test (Celsius) 18.7 20.8 22.4 Relative Humidity at end of test (% RH) 40.2 35.6 39.8 Moisture reading in toe at start of test (moisture units) 95 96 94 Moisture reading in toe at end of test (moisture units) 93 92 92 Moisture reduction in moisture in toe (moisture units) 2 4 6 Average reduction of moisture in toe (moisture units) 4 Moisture reading in ankle at start of test (moisture units) 85 81 Moisture reading in ankle at end of test (moisture units) 83 79 , Moisture reduction in moisture in ankle (moisture units) 2 2 7 Average reduction of moisture in ankle (moisture units) 3.7 Table 2. Second set of tests Test 4 , Test 5 Test 6 Temperature at start of test (Celsius) 20.9 20.9 19.4 Relative Humidity at start of test (% RH) 48.5 40.6 51.4 Temperature at end of test (Celsius) , 18.7 . 20.8 22.4 Relative Humidity at end of test (% RH) 40.2 35.6 39.8 Moisture reading in toe at start of test (moisture units) 93 92 Moisture reading in toe at end of test (moisture units) 54 53 52 Moisture reduction in moisture in toe (moisture units) 39 39 40 Average reduction of moisture in toe (moisture units) 39.3 Moisture reading in ankle at start of test (moisture units) 77 81 Moisture reading in ankle at end of test (moisture units) 39 44 37 Moisture reduction in moisture in ankle (moisture units) 38 37 41 Average reduction of moisture in ankle (moisture units) 38.7 x Table 3. Third set of tests Test 7 Test 8 Test 9 Temperature at start of test (Celsius) 20.2 20.2 Relative Humidity at start of test (% RH) 49.9 49.9 46.4 Temperature at end of test (Celsius) 20.3 20.3 20.5 , Relative Humidity at end of test (% RH) 43.4 43.4 Moisture reading in toe at start of test (moisture units) 92 92 Moisture reading in toe at end of test (moisture units) 56 50 Moisture reduction in moisture in toe (moisture units) 26 42 Average reduction of moisture in toe (moisture units) 33.3 Moisture reading in ankle at start of test (moisture units) 75 75 Moisture reading in ankle at end of test (moisture units) 49 47 Moisture reduction in moisture in ankle (moisture units) 36 28 Average reduction of moisture in ankle (moisture units) 35.3 Table 4. Fourth set of tests Test 10 Test 11 Test 12 Temperature at start of test (Celsius) 22 23 Relative Humidity at start of test (% RH) 46.4 56.7 56.7 Temperature at end of test (Celsius) 20.5 , 23.4 23.4 Relative Humidity at end of test (% RH) 47 47.7 47.7 Moisture reading in toe at start of test (moisture units) 90 82 Moisture reading in toe at end of test (moisture units) 48 51 Moisture reduction in moisture in toe (moisture units) 42 31 Average reduction of moisture in toe (moisture units) 37.6 Moisture reading in ankle at start of test (moisture units) 78 _ 60 Moisture reading in ankle at end of test (moisture units) 27 37 Moisture reduction in moisture in ankle (moisture units) 51 23 Average reduction of moisture in ankle (moisture units) 33 A
Table 5. Fifth set of tests Test 13 Test 14 Test 15 Temperature at start of test (Celsius) 15.3 22.5 23.3 Relative Humidity at start of test (% RH) , 79 45.3 Temperature at end of test (Celsius) 22.5 22.5 23.9 Relative Humidity at end of test (% RH) 43.5 41.3 45.3 Moisture reading in toe at start of test (moisture units) 95 93 Moisture reading in toe at end of test (moisture units) 58 58 Moisture reduction in moisture in toe (moisture units) 37 35 Average reduction of moisture in toe (moisture units) 32.3 Moisture reading in ankle at start of test (moisture units) 91 86 Moisture reading in ankle at end of test (moisture units) 72 53 Moisture reduction in moisture in ankle (moisture units) 19 23 Average reduction of moisture in ankle (moisture units) 30 The invention has been described by way of examples only. Therefore, the foregoing is considered as illustrative only of the principles of the invention.
Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the claims.

Claims (17)

Claims

1. A shoe dryer arranged to insert into a foot cavity of a shoe and dry the shoe from the inside out, comprising a foot shaped container having a toe and ankle to insert into the foot cavity so as to remove moisture from the inside of the shoe, the container comprising a lattice extending from toe to ankle defining a Voronoi pattern of spaces through a container wall to provide a passageway for air inside the shoe.

2. A shoe dryer according to claim 1, wherein the container is rigid.

3. A shoe dryer according to claim 2, wherein the container has a substantially right angle proximate a heel intermediate the toe and ankle.

4. A shoe dryer according to any one of claims 1 to 3, wherein the lattice forms a hollow interior of the container to contain a drying material to remove moisture from the air inside the shoe.

5. A shoe dryer according to claim 4, wherein the container comprises an opening proximate the ankle for loading the drying material into the container.

6. A shoe dryer according to any one of claims 1 to 5, wherein the container is formed of two halves joined along a surface of separation extending from toe to ankle.

7. A shoe dryer according to claim 6 when dependent on claim 4, where the two halves are separable and re-joinable along the surface of separation whereby the container is loadable with drying material.

8. A shoe dryer according to any one of claims 1 to 7, wherein the shape of the Voronoi pattern of spaces is determined by virtual seed points spaced along the container such that included angles of the lattice are at least forty degrees.

9. A shoe dryer according to any one of claims 5 to 8 when dependent on claim 4, comprising a sock to hold the drying material in a granular form; the sock of length to extend from toe to ankle of the container and sock permeable to water and airborne moisture.

10. A shoe dryer according to claim 9, wherein the sock comprises an outer layer comprising a mesh permeable to water and airborne moisture.

11. A shoe dryer according to claim 10, wherein the sock comprises a lining joined to the inside of the outer layer whereby intermediate the lining and outer layer there is formed a compartment to contain the granular drying material.

12. A shoe dryer according to any one of claims 9 to 11, comprising a rigid former to insert into and support the sock from toe to ankle of the container, and thereby to support the granular drying material from toe to ankle within the container.

13. A shoe dryer according to claim 12, wherein surface of the rigid former is smooth.

14. A shoe dryer according to claim 12, wherein the rigid former comprises a lattice extending from toe to ankle defining a Voronoi pattern of spaces through the rigid former to provide a passageway for the air.

15. A shoe dryer according to any one of claims 1 to 14, formed of material with a melting temperature above 220 degrees centigrade.

16. A shoe dryer according to any one of claims 1 to 15, wherein the lattice of the container comprises an embedded resistance heater suitable for heating the lattice and drying material contained in the container to release moisture captured by the drying material.

17. A shoe dryer according to any of claims 4, or any of claims 5 to 16 when dependent on claim 4, wherein the container comprises the drying material to remove moisture from the air inside the shoe.