Abstract:
A footwear dryer is disclosed. The footwear dryer includes a ducted portion, a heating element positioned within the ducted portion that heats air passing over the heating element, a forced air generation device positioned within the ducted portion and oriented to force air through the ducted portion and over the heating element, and a power source configured to provide 12 volts or less and to power to the forced air generation device.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present disclosure claims priority to U.S. provisional application No. 62/338,848 entitled “Ducted Footwear Dryer,” filed on May 19, 2016, which is hereby incorporated by reference herein in its entirety. 
     
    
     BACKGROUND 
       [0002]    Many traditional footwear dryers use high voltages (e.g., 119V) to power their electrical components. Because traditional footwear dryers typically require such high voltage sources, the locations where they may be used is limited to those locations where high voltage power sources are available, such as traditional power outlets coupled to a power grid. Additionally, many traditional footwear dryers are floor mounted, meaning that the footwear dryer is connected to a stand or mount that sits on the ground, and the boot is inverted and placed on the footwear dryer. This limits portability as the footwear dryer must have a sufficiently large base to prevent the footwear dryer from becoming top heavy when a boot is placed on it. 
       SUMMARY 
       [0003]    According to an embodiment, a footwear dryer is disclosed. The footwear dryer includes a ducted portion, a heating element positioned within the ducted portion that heats air passing over the heating element, a forced air generation device positioned within the ducted portion and oriented to force air through the ducted portion and over the heating element, and a power source configured to provide 12 volts or less and to power to the forced air generation device. 
         [0004]    According to another embodiment, a footwear dryer is disclosed. The footwear dryer includes a first ducted section, a second ducted section coupled to the first ducted section at an angle, a heating element anchored to an interior portion of the first section, a forced air generation device anchored to the interior portion of the first section, and a power supply that provides power to the heating element and the forced air generation device, wherein the power supply provides a voltage of 12V or fewer. 
         [0005]    According to another embodiment, a footwear dryer is disclosed. The footwear dryer includes a flow structure defining a flow pathway therethrough, a ceramic heater anchored to an interior surface of the ducted portion, a fan anchored to the interior surface of the ducted portion, a low voltage power supply coupled to the ceramic heater and the fan, and a coating on an exterior surface of the ducted portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of a portable, ducted footwear dryer. 
           [0007]      FIG. 2  is a cross-sectional view of the footwear dryer of  FIG. 1  taken along the line  2 - 2 . 
           [0008]      FIG. 3  is a cross-sectional view of the footwear dryer of  FIG. 1  taken along the line  3 - 3 . 
           [0009]      FIG. 4  is a cross-sectional view of a boot and the footwear dryer of  FIG. 1 . 
           [0010]      FIG. 5  is a partial cutaway view of a footwear dryer having a ceramic heater. 
           [0011]      FIG. 6  is a functional block diagram of the footwear dryer of  FIG. 1 . 
       
    
    
     OVERVIEW 
       [0012]    Embodiments disclosed herein describe a portable, ducted footwear dryer for use with a universal serial bus (USB) power source. The footwear dryer may generally have a first section and a second section. In one embodiment, the second section may be oriented at approximately a 90° angle to the first section. In other embodiments, the second section may be oriented at a different angle (e.g., 60°) or no angle. The first and second sections may generally be hollow tubes or pipes. A heater and a forced air generation device may be positioned within the first section. The forced air generation device is configured to draw air through an open portion of the first section, and propel the air out of an open portion of the second section. As the air passes through the first section, the heater heats the air, which is then propelled out of the open portion of the second section. The heater and the fan may be powered by an external power source through, for example, a USB power cable. By using a USB power cable, the footwear dryer may take advantage of portability by allowing the footwear dryer to be used wherever a USB outlet is available, such as in an automobile. Selection of the type of heater and the forced air generation device is such that both may be operated based on a relatively low voltage power source, such as 5V provided by standard USB power sources. 
       DETAILED DESCRIPTION 
       [0013]      FIG. 1  is a perspective view of a portable, ducted footwear dryer, generally designated  100 . The footwear dryer  100  generally includes a first section  102  and a second section  104 . The first section  102  has an open portion  106 . The second section  104  has an open portion  108 . The first section  102  and the second section  104  may include one or more pipe sections  110  and a coating  112 . The pipe  110  creates a flow structure defining a flow pathway therethrough. The pipe sections  110  may be, for example, polyvinyl chloride (PVC) pipe. In other embodiments, other types of piping may be used, such as chlorinated polyvinyl chloride (CPVC) pipe, steel, aluminum, brass, wood, bamboo, etc. The pipe  110  may have a generally circular cross section to form a duct to guide forced air through the first and second sections. In other embodiments, the pipe  110  may have different cross-sectional shapes. In various embodiments, the first section  102  and the second section  104  may be a single, integrally formed pipe  110 . In other embodiments, the first section  102  and the second section  104  may include two pipes  110  connected with a connection portion (not shown), such as an elbow joint. The first section  102  may be longer than the second section  104 . By increasing the length of the first section  102 , the first section  102  may aid to hold a portion of the footwear up, as in the case of long boots, to improve the drying process. 
         [0014]    The pipe  110  may be partially or completely covered by the coating  112 . In various embodiments, the coating  112  may be made of any suitable type of insulation such as rubber insulation, foam insulation, or other suitable material. In other embodiments, the coating  112  may include paint, tape, or other wraps, coatings, or materials. The coating  112  may improve the heat transfer properties of the footwear dryer  100  during operation to increase the amount of thermal energy output through the opening  108  of the second section  104  in the form of heated, forced air and to decrease the loss of thermal energy transferred through the pipe  110  of the first section  102  and the second section  104 . 
         [0015]    The footwear dryer further includes a power cable  114  coupled to a plug  116 . The power cable  114  and plug  116  may provide power to a forced air generation device (see  FIG. 2 ) and a heater (see  FIG. 2 ). The forced air generation device and the heater are discussed in further detail below with respect to  FIGS. 2 and 3 . The power cable  114  and the plug  116  are configured to operate using a relatively low voltage power source (e.g., 12V or less). The power cable  114  may enable users to operate the footwear dryer  100  even when a standard 119V outlet is not available for use. For example, many automobiles are beginning to include USB ports for charging various electronic devices, such as mobile phones. By powering the footwear dryer  100  with a USB power source, the footwear dryer  100  may take advantage of new power sources that were previously unavailable for footwear dryers. In various embodiments, the power cable  114  and plug  116  may be USB standard compliant, for example, USB 1.0, 2.0, 3.0, 3.1, Type-B, Type-C, or micro-USB. However, footwear dryers have traditionally been unsuited to low voltage power sources because the electrical elements included in the footwear dryer require too high of voltage or current to be suitable for use with low voltage power sources. The power cable  114  and plug  116  may be configured to provide a predetermined voltage (e.g., +5V) and a particular current (e.g., up to 3 A) to provide power (e.g.,  15 W) to the forced air generation device and the heater. Traditional footwear dryers use high voltage power sources, such as standard 119 V outlets connected to a power grid, in order to provide sufficient power levels to activate the heater. By employing a low power consumption heater with a forced air, ducted design, embodiments herein are able to take advantage of the low voltage power supplies that are becoming increasingly available in automobiles, homes, laptop computers, etc., such as USB ports, allowing the dryer to be more portable, consume less energy, and be able to be used in more locations as compared to conventional footwear dryers. 
         [0016]      FIG. 2  is a cross-sectional view of the footwear dryer  100  of  FIG. 1  taken along the line  2 - 2 . As shown in  FIG. 2 , the footwear dryer  100  may include a heater  202  and a fan  204 . The fan  204  may have a plurality of blades  206 . The fan may further include a number of anchors  208 . 
         [0017]    The fan  204  is one example of a forced air generation device, as discussed above with respect to  FIG. 1 . The fan may be positioned above or below the heater  202  in the first section  102 . The fan  204  may be secured in place by the anchors  208  (e.g., screws, glue, nails, etc.), which fix the fan  204  to the interior of the pipe  110 . The fan may be coupled to the power cable  114  and the plug  116 . The power cable  114  provides power to the fan  204  to drive an electric motor configured to rotate the blades  206  to draw air in the open portion  106  of the first section  102 , over the heater  202 , and expel the air from the open portion  108  of the second section  104 . The power cable  114  may be configured to be inserted in a groove formed in the outside of the pipe  110 . The groove holds the power cable  114  in place and directs the power cable to the top of the footwear when the footwear dryer is inserted inside a boot or other item of footwear. The power cable  114  may be fixed in place, for example, with electrical tape and/or an adhesive prior to the application of the coating  112 . 
         [0018]    The blades  206  of the fan  204  may extend to an interior wall of the first section  102 . In other words, the fan  204  may have a diameter that is selected to correspond to the diameter of the interior wall  102  in order to help retain the fan in place and ensure maximum air flow by maximizing the size of the blades. In operation, the heated air forced through the open portion  108  of the second section  104  may warm the interior of the boot and dry any moisture retained in the boot fabric. In various embodiments, the fan  204  may be a brushless thermal management fan. By using a brushless motor, the lifespan of the footwear dryer  100  may be increased. For example, in some embodiments, a brushless motor may have a lifespan of about 35,000 hours, whereas brushed fans may have a lifespan of only about 300 hours. The fan  204  may be configured to operate based on a 5V power supply and may be configured to draw up to 0.08 A of current. By containing the fan within the ducted portion of the pipe  110 , increased airflow not available in traditional footwear dryers may be achieved. For example, the fan  204  may provide approximately 200 ft. 3 /min of air. 
         [0019]    As shown in  FIG. 2 , the heater  202  may be, for example, a wire mesh or netting heater. The heater  202  may be coupled to the power cable  114  and configured to receive power through the plug  116 . The heater  202  may convert the electrical energy into thermal energy, for example, through resistive heating. The heater may extend across the diameter of the pipe  110 . The heater  202  may define a number of openings to allow air to pass through the wire mesh/netting. Although shown as a wire mesh heater, a number of alternative heaters may be used. For example, the heater  202  may be a ceramic heater, a ring heater, a band heater, a silicone or polymide film heating pad, a tube heater, a coil heater, or any other suitable heater, so long as the heater is capable of being operated by a low voltage USB power source (e.g., 5V). In some embodiments, the heater  202  may be omitted. 
         [0020]    Embodiments of the present disclosure recognize that there is a trade-off in powering the fan versus powering the heater. In various embodiments, the fan may be configured to operate at 5V and consume 0.1 A while the heater may be configured to operate at 5V and consume 0.9 A. Such a combination of voltage and current draw may be desirable because it enables a majority of the current to be provided to the heater to improve the efficiency of the drying process by increasing the temperature of the forced air. 
         [0021]      FIG. 3  is a cross-sectional view of the footwear dryer of  FIG. 1  taken along the line  3 - 3 . As discussed above with respect to  FIG. 2 ,  FIG. 3  shows the heater  202  and the fan  204  positioned within the first section  102 . During operation, the power cable  114  and plug  116  provide power to the heater  202  and the fan  204 . The blades  206  of the fan rotate, creating a pressure differential within the footwear dryer  100 . As a result of the pressure differential, cool air  302  is drawn into the first section  102  of the footwear dryer  100  through the open portion  106 . As the air  302  passes through the first section  102 , it passes over the heater  202 , which is heated with power from the power cable  114  and the plug  116 . The air  302  is heated as it passes over or through the heater  202  to create heated air  304 . The fan  204  propels the heated air  304  through the remainder of the first section  102  and through the second section  104 . The expelled air  306  exits the open portion  108  of the second section  104  and heats/dries the interior of the boot. 
         [0022]      FIG. 4  is a cross-sectional view of a boot  402  and the footwear dryer  100  of  FIG. 1 . The footwear dryer  100  may be placed within the foot opening  404  of the boot  402  such that the second section  104  is in contact with the interior sole  406  of the boot  402 . Because the footwear dryer  100  is configured to operate with the footwear dryer  100  inserted substantially within the boot  402 , eliminating the need for a bulky stand or support structure for the footwear dryer  100 . The boot itself may provide the support for the footwear dryer  100 . By containing the fan  204  within the first section  102 , the footwear dryer  100  may be inserted entirely or nearly entirely within the boot  402 . By containing the footwear dryer  100  substantially within the boot  402 , portability may be increased by eliminating external fans or components that may be cumbersome or cause the boot to become top heavy, etc. and allows the boot  402  to be dried in any orientation or configuration. The boot  402  is not required to be upright or near the other boot to operate effectively. The plug  116  may be connected to a USB port, such as an automobile USB port, to provide electricity to the footwear dryer  100 . The fan  204  may draw cool air  302  through the open portion  106 , across the heater  202  (not shown in  FIG. 4 ), and propel heated, expelled air  306  through the open portion  108  of the second section  104 . Accordingly, the expelled air  306  may dry the interior of the boot  402  using a low voltage power source, such as a 5V USB power source. 
         [0023]      FIG. 5  is a partial cutaway view of a footwear dryer including a ceramic heater  502 . The ceramic heater  502  may be placed within the first section  102  of the footwear dryer  100  and replace the heater  202 . The ceramic heater  502  may include a number of ceramic elements  504  arranged in a cylindrical shape that generate heat when an electric current is applied to a coil in thermal contact with the ceramic elements  504 . The electric current heats the coil and the heat is transferred to the ceramic elements  504  by conduction and/or induction. The ceramic elements  504  then radiate heat to the cooler air. The ceramic elements may be arranged in a ring shape to define a cavity  508 . During operation, the fan may draw air  506  through the open portion  106  and through the cavity  506 . In these embodiments, due to the ring shape of the heater, the open cavity  508  may be free from obstructions that would otherwise require a higher power fan or blower to compensate for the reduced flow area. As the air passes through the cavity  508 , the air heats up due to the proximity to the ceramic elements  504 . Power to the ceramic heater  502  may be supplied by the power cable  114  and the plug  116 , which may be connected to a low voltage power supply, such as a USB port. 
         [0024]      FIG. 6  is a functional block diagram of the footwear dryer  100  of  FIG. 1 . The footwear dryer  100  generally includes a low voltage power supply  602 , a fan  604 , and a heater  606 . The low voltage power supply may generally be any type of supply configured to provide a low voltage (e.g., 12V or less). For example, the low voltage power supply  602  may be a USB port in an automobile. The fan  604  and the heater  606  may be implemented as described above with respect to the fan  204  and the heater  202 , respectively. In various embodiments, the fan  604  and the heater  606  may be selected to operate in combination at no more than the voltage level supplied by the low voltage power supply  602 .