Technical Field of the Invention

The present invention relates generally to heated footwear and more particularly to heated overshoes and boots worn over existing footwear.

Background to the Invention

Heated shoeboxes into which shoes or boots can be placed when not being worn are known.

Chinese Utility Model No. CN206498546 discloses a heating device that could be comprised of a box body, a box lid, heating wire, shoe rack, temperature sensor, control button, temperature display screen, time display, and a timer, wherein shoes could be placed on the shoe racks provided within and the box cover is closed, power switch then could be turned on to operate and temperature of the heating wire set by the control button, wherein a timer could be configured to control the operation timing of heating wires.

United States Patent Publication No. US2006248747 discloses an insulating envelope or sheath (sometimes termed herein as an overshoe) which has heating elements within it which may be actuated by a battery source, either rechargeable or not. This overshoe includes a heating element attached in or on the overshoe, so that with a source of electrical energy, such as a battery, the heating element can be actuated to provide heat to the area of the overshoe which encompasses the wearer's foot in areas vulnerable to the cold, preferably at least the toes of the foot. Suitably it extends to other areas of the foot as well. Usually, it does not cover the sole of the boot as that would interfere with some activities such as skiing, hiking, ice skating and the like.

Similarly, United States Patent Publication No. US2004250445 discloses an insulating covering is provided to fit over a boot or shoe and at least partially encompass the toe area of the boot and shoe. The insulating covering has a receiver or pocket to hold a heat generating device. A conventional heat generating device, such as an air activated heat generating packet or fuel stick heating device may be placed in the receiver. The insulating covering has laces, cords or straps to firmly attach the insulating covering to the boot or shoe. The laces, cords or straps may be elastic and tensioned with a fastener. The insulating covering may be water repellent or waterproof, including being formed of a breathable fabric.

Summary of the Invention

According to a broad aspect of the invention, there is provided a heated overshoe comprising: a) a sole portion, b) an upper portion sized and configured to fit over a shoe worn by a user, encompassing at least the shoe, c) at least one closure mechanism provided in the upper portion to open and close at least a portion of the upper portion for donning and doffing the heated overshoe and d) at least one heat generating device provided in at least the upper portion.

Providing a heated overshoe to encompassing at least the shoe on a user, in other words, whilst being worn by a user allows the user to maintain warmth in their feet, shoes whilst they are worn and to allow the heated overshoe to be easily removed when not required.

The upper portion of the heated overshoe may comprise an elongate shaft portion extending upwardly from the upper portion and configured to encompass a part of the calf of the user, above the user’s ankle. The provision of an elongate shaft portion means that the heated overshoe can be used to heat a boot and/or lower leg portion of the user, while a shoe or boot is worn.

The heated overshoe is preferably used, donned over a shoe while the shoe is worn by the wearer.

The heated overshoe may encompass the shoe in its entirety. An elongate shaft portion may encompass an upper part of a boot and/or a lower part of the wearer’ s lower leg.

Heating may be provided relative to the sole portion of the heated overshoe, but preferably, heat is provided relative to the upper portion of the heated overshoe only. The heated overshoe may be used in ambient temperatures of between 10°C and -20°C. A controller may be provided to control the function of the at least one heat generating device.

The heated overshoe may be capable of operation for at least two hours. The at least one heat generating device may deactivate after prolonged continuous operation. At least one timer may be provided to deactivate the at least one heat generating device. The at least one timer may be adjustable. The at least one timer may be provided with a reset function or actuator allowing a wearer to manually reset the at least one timer to continue operation. The time period may be set at any suitable length of time for example, 10 minutes, 20 minutes, 30 minutes or longer time periods.

The heated overshoe is preferably configured for operation in all weather conditions. The heated overshoe may be water resistant or repellent.

The heated overshoe is preferably provided in pairs. The pairs of shoes may be configured as a pair, that is to say, left and right overshoes, with different shapes/configurations, or the heated overshoes in a pair may have the same configuration. The heated overshoes in a pair may be independent and separate. The heated overshoes in a pair may be operable as a pair, that is together or separately. There may for example be wireless communication between one overshoe and the other overshoe in a pair and/or one or both overshoes may be in wireless communication with a separate controller, such as a software application operating on a smartphone, computer or tablet for example.

The heated overshoe comprises a sole portion. The sole portion may comprise a substantially planar sole plate. The sole portion may be semi-rigid or rigid.

The upper portion is preferably attached to the sole portion. Any attachment mechanism or method may be used. For example, stitching and/or adhesive could be used to attach the upper portion to the sole portion about an outer edge of the sole portion.

The sole portion may be shaped. The same shape of sole portion may be used for each of the heated overshoes in a pair or differently shaped, left and right sole portions may be used. The sole portion may be oversized. If the wearer is a size UK42, then the sole portion will preferably be larger than that to allow the heated overshoe to encompass the shoe while it is worn.

The sole portion may be made from any material but a polymeric material such as polyurethane may be preferred, to provide a cushioning effect.

The heated overshoe comprises an upper portion sized and configured to fit over a shoe worn by a user, encompassing at least the shoe. As mentioned above, the upper portion may be attached, preferably permanently, to the sole portion.

The upper portion may be formed of a multilayer construction, comprising one or more fabric and/or textile layers. The at least one heat generating device may be provided as, or as a part of a layer. Each of the layers is preferably concentric. Each layer is preferably continuous when formed, except for a suitable at least one closure mechanism provided in the upper portion to open and close at least a portion of the upper portion for donning and doffing the heated overshoe.

The upper portion may be formed by assembling the layers on one another in the desired order and then attaching one or more layers together and/or to the sole portion.

The upper portion may be shaped. The upper portion is sized and configured to fit over a shoe worn by a user, encompassing at least the shoe and may comprise a tow cap or box, a vamp, a heel counter and a quarter. Preferably, the upper portion will not include a tongue.

The upper portion may include one or more pockets. The or each pocket may be used for retaining a battery or power pack to provide power to the at least one heating device. The or each pocket may be accessible from outside the upper portion. The or each pocket may be attached to an outer side of an outer layer of the upper portion. A closure may be provided on the or each pocket. A flap with closure mechanism for example Velcro® or a clip may be provided on the or each pocket. This may allow the pocket to be opened to access the battery or power pack for removal and/or replacement and to be closed and secured to retain the battery or power pack therein. The upper portion may include an outer layer. The outer layer may preferably be a protective layer to minimise damage to the upper portion. The outer layer may be waterproof or at least water resistant or water repellent. The outer layer may be treated to achieve this. The outer layer may be a woven fabric layer. A woven polymeric material may be used. The polymeric material may comprise polyester and may comprise a polyvinyl coated polyester. A suitable material for the outer layer is a nylon or similar material. A blend of Nylon and cotton or other material fibres could be used. Cordura® fabric is one example of a material which could be used for the outer layer.

Any edges or seams of the outer layer may comprise a fabric or webbing covering or tape, which in use, help to mitigate damage and/or heat loss through the edges/seams.

The upper portion may include a thermally insulating layer. The thermally insulating layer may be provided adjacent to (abutting) an inner side of the outer layer. The thermally insulating layer may be provided as a layer of formed of thermally insulating material such as fleece insulation or wadding for example.

The thermally insulating material may be selected from wool, cotton, paper, card, a polymeric material or any combination thereof. The polymeric material may be selected from polyester, polyurethane, polyvinyl chloride, polyamide, or any combination thereof, for example. A polyester fibre layer could be used.

The upper portion may include a heat reflective layer. The heat reflective layer may be provided adjacent to (abutting) an inner side of the thermally insulating layer. Preferably the heat reflective layer comprises metal foil on a sheet of polymeric material, or a metallised polymeric material. The polymeric material may comprise polyvinyl chloride or polyester. The heat reflective layer may comprise a metallised polymeric film laminated to a cellular or “bubble” layer. The cells or bubbles of the cellular or bubble layer may be filled with air, nitrogen or other suitable gases.

The layer of metal foil or metallised polymeric material may be located on the face of the heat reflective layer that faces the thermally insulating layer of the upper portion. The metal of the metal foil or metallised polymeric material may be aluminium. The heat reflective lay may be an aluminised Mylar IR reflective layer.

The polymeric sheet of the heat reflective layer may comprise a polyester material optionally coated with polyvinyl chloride. The polyvinyl chloride may be coated on both sides of the polyester material.

The metal foil of the heat reflective layer may comprise a layer of metal foil, such as an aluminium foil.

The upper portion may include a second thermally insulating layer. The second thermally insulating layer may be the same as or similar to the thermally insulating layer provided between the outer layer and the heat reflective layer, except that the second thermally insulating layer may be provided adjacent to (abutting) an inner side of the heat reflective layer.

As mentioned above, the at least one heat generating device may be provided as, or as a part of a layer. The at least one heat generating device is preferably flexible. The at least one heat generating device may be or include a flexible heating layer. The flexible heating layer may be bonded to a flexible carrier layer.

In one embodiment, the flexible heating layer is provided adjacent to (abutting) an inner side of the second thermally insulating layer.

In one embodiment, the flexible heating layer is a carbon fibre heating element layer bonded to carrier layer. Such a heating layer requires low power density, which prevents the formation of hotspots. An example of a flexible heating layer is one manufactured by Embro GmbH Germany.

Any preferably flexible heat generating device could be used for example, a polyimide flexible heater, such as those manufactured by OMEGA Engineering Inc. could be used.

The at least one heat generating device is preferably electrically powered and connected to a battery or power pack to provide electric power to the at least one heat generating device. The connection may be a wired connection extending through/between any layers outside the preferred heating layer to an outside of the upper portion.

The upper portion may comprise an inner layer. The inner layer may be similar to or the same as the outer layer. The inner layer may be provided adjacent to (abutting) an inner side of the at least one heat generating device layer.

A preferred order of layers in the upper portion may be: outer layer, first thermally insulating layer, heat reflective layer, second thermally insulating layer, heating layer and inner layer. The layers may preferably be provided in a stack or sandwich. The order may be as provided above.

The layers in the upper portion may be attached together. The layers in the upper portion may be attached together in certain locations and not in other locations. For example, the layers may be attached together about a perimeter, near the sole portion, and about the at least one closure mechanism but may be otherwise not attached to one another.

Any suitable attachment method or mechanism may be used to attach the layers to one another, for example stitching and/or adhesive.

Further, some layers may be attached to certain other layers but not to certain other layers. For example, it is preferable that the heating layer is not stitched anywhere but about a perimeter edge as to do otherwise may affect the heating device adversely.

The heated overshoe comprises at least one closure mechanism provided in the upper portion to open and close at least a portion of the upper portion for donning and doffing the heated overshoe. The at least one closure mechanism is preferably provided in the upper portion.

The at least one closure mechanism may be provided a forward side of the upper portion or a rear side of the upper portion. The at least one closure mechanism may be provided approximately centrally, at or close to a midline of the upper portion when the heated overshoe is worn. This will preferably make the at least one closure mechanism easily accessible for a wearer. Any type of at least one closure mechanism may be used. More than one type of closure mechanism could be used. In one form, the closure mechanism may be an elongate zipper. An elongate flap may be provided over the length of the zipper to better retain heat. The elongate flap may be retained in a closed condition using one or more clips, or buttons or Velcro® for example.

The heated overshoe comprises at least one heat generating device provided in at least the upper portion. As mentioned above, the at least one heat generating device may be provided relative to the upper portion only and not the sole portion.

The heated overshoe may comprise a battery or power pack. The battery or power pack is preferably connected to the at least one heat generating device to power the at least one heat generating device. A single battery may be provided or a power pack comprising more than one battery could be used.

In one form, any battery or cell may be a lithium chemistry type, based on common 18650 packaged cells. The battery or power pack may be provided with a charging and protection circuit to prevent damage due to overcharging or overdischarging. The circuit may also incorporate a timer to provide an auto- shutdown feature. Cylindrical 18650 cells may be preferred as they are resistant to impact damage, are readily available and can provide high power density.

The heated overshoe may comprise a sensing device. The sensing device may sense operating parameters of the heated overshoe such as temperature, time elapsed, power charge remaining etc. The sensing device may sense ambient conditions and adjust the operation of the at least one heat generating device accordingly.

Detailed Description of the Invention

In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

Figure 1 axonometric front view of a pair of heated overboots according to an embodiment. Figure 2 is an axonometric side view of the pair of heated overboots illustrated in Figure 1.

Figure 3 is an axonometric side view of one of the pair of heated overboots illustrated in Figure 1 with the battery pack removed from the battery pocket.

Figure 4 is a top view of the pair of heated overboots illustrated in Figure 1.

Figure 5 is a side view of the configuration illustrated in Figure 3.

Figure 6 is an axonometric view of the pair of heated overboots illustrated in Figure 1 showing the soles.

Figure 7 is an axonometric top view of the pair of heated overboots illustrated in Figure 1 in use with one overboot opened for donning and doffing.

In the embodiment illustrated in the accompanying Figures, a pair of heated overboots 10 are provided. Each of the pair of heated overboots 10 comprises a sole 11, an upper portion 12 sized and configured to fit over a shoe 13 worn by a user, encompassing at least the shoe 13, and at least one closure mechanism 14 provided in the upper portion 12 to open and close at least a portion of the upper portion 12 for donning and doffing the heated overshoe 10. At least one heat generating device (not visible) is provided in at least the upper portion of each of the heated overshoes in the form of a flexible heating layer (not visible).

As shown in the Figures, the upper portion 12 of the heated overshoe 10 comprises an elongate shaft portion 15 extending upwardly from the upper portion 12 and configured to encompass a part of the calf of the user, above the user’s ankle as shown in Figure 7. The provision of an elongate shaft portion 15 means that the heated overshoe 10 can be used to heat a boot and/or lower leg portion of the user, while a shoe or boot is worn.

The heated overshoe 10 of the illustrated embodiment is preferably used donned over a shoe 13 while the shoe 13 is worn by the wearer as shown in Figure 7.

The heated overshoe 10 encompasses the shoe 13 in its entirety. The heated overshoe is preferably provided in a pair as shown. The pairs of heated overshoes shown are configured as a pair, that is to say, left and right overshoes, with the same shape/configuration, but with the pocket 16 on opposite sides thereof. The pocket 16 may then be located to the outside of the foot over which the heated overshoe is worn as shown in Figure 1.

The heated overshoes 10 in a pair are independent and separate. The at least one heating device of each heated overshoe is independently actuable between on and off and the timers for the respective heated overshoes 10 operate separately.

The heated overshoe 10 comprises a sole 11. The sole of the illustrated embodiment is a substantially planar sole plate. The sole 11 is semi-rigid.

The upper portion 12 is attached to the sole 11 as shown in Figure 6 in particular. Any attachment mechanism or method may be used. For example, stitching and/or adhesive could be used to attach the upper portion 12 to the sole 11 about an outer edge of the sole 11 as illustrated in Figure 6.

The sole 11 is oversized. If the wearer is a size UK42, then the sole 11 will be larger than that, to allow the heated overshoe 10 to encompass the shoe 13 while the shoe is worn.

The sole 11 can be made from any material. In the illustrated embodiment, a polyurethane material is used to provide a cushioning effect.

The upper portion 12 of the illustrated embodiment is formed using a multilayer construction, comprising one or more fabric and/or textile layers. The at least one heat generating device (not shown) is provided as, or as a part of one of the layers. Each of the layers is preferably concentric. Each layer is continuous when formed, except for a suitable closure mechanism 14 provided in the upper portion 13 to open and close at least a portion of the upper portion 12 for donning and doffing the heated overshoe 10.

The upper portion is formed by assembling the layers on one another in the desired order and then attaching one or more layers together and/or to the sole 11.

The upper portion 12 of the illustrated embodiment is boot shaped. The upper portion 12 is sized and configured to fit over the shoe 13 worn by a user, encompassing at least the shoe 13. As illustrated, the upper portion does not include a tongue with the closure mechanism 14 located where a tongue would normally be located in a conventional boot or shoe.

The pockets 16 of the respective heated overshoes 10 are used for retaining a power pack 17 with one or more cells or batteries to provide electrical power to the at least one heating device. Each pocket 16 is accessible from outside the upper portion 12. Each pocket is attached to an outer side of an outer layer of the upper portion 12 as shown in Figure 2.

A flap 18 with Velcro® closure 19 is provided on the or each pocket. This allows the pocket 16 to be opened to access the power pack 17 for removal and/or replacement, and to be closed and secured to retain the power pack 18 therein.

The layers forming the upper portion 12 of the illustrated embodiment are as follows:

1. An outer layer which is a protective layer to minimise damage to the upper portion. The outer layer is waterproof or at least water resistant or water repellent. The outer layer may be treated to achieve this. A woven polyvinyl coated polyester is used for the outer layer. Cordura® fabric is used for the outer layer of the illustrated embodiment.

2. A first thermally insulating layer is provided adjacent to (abutting) an inner side of the outer layer. The first thermally insulating layer may be provided as a layer of formed of thermally insulating material such as fleece insulation or wadding for example.

3. A heat reflective layer is provided adjacent to (abutting) an inner side of the thermally insulating layer. The heat reflective layer of the illustrated embodiment is a metal foil on a sheet of polymeric material, or a metallised polymeric material. The metal of the metal foil or metallised polymeric material is aluminium. The heat reflective lay of the illustrated embodiment is an aluminised Mylar IR reflective layer.

4. A second thermally insulating layer which is the same as or similar to the first thermally insulating layer is provided adjacent to (abutting) an inner side of the heat reflective layer. 5. The at least one heat generating device is provided as, or as a part of a layer. The at least one heat generating device is or includes a flexible heating layer. The flexible heating layer may be bonded to a flexible carrier layer. The flexible heating layer is provided adjacent to (abutting) an inner side of the second thermally insulating layer. In the illustrated embodiment, the flexible heating layer is a carbon fibre heating element layer bonded to carrier layer. Such a heating layer requires low power density, which prevents the formation of hotspots. The flexible heating layer is electrically powered and connected to the power pack 17 to provide electric power. The connection of the illustrated embodiment is a wired connection extending through/between any layers outside the heating layer to an outside of the upper portion 12.

6. An inner layer is provided adjacent to (abutting) an inner side of the flexible heating layer. The inner layer of the illustrated embodiment is the same material as the outer layer.

The layers are provided in a stack or sandwich in the order as provided above.

The layers in the upper portion 12 may be attached together. The layers in the upper portion 12 may be attached together in certain locations and not in other locations. For example, as shown, the layers are attached together about a perimeter, near the sole 11, and about the closure mechanism 14.

Any suitable attachment method or mechanism may be used to attach the layers to one another, for example stitching and/or adhesive.

Further, some layers may be attached to certain other layers but not to certain other layers. For example, it is preferable that the heating layer is not stitched anywhere but about a perimeter edge as to do otherwise may affect the heating device adversely.

As shown in Figure 6 in particular, any edges or seams of the upper portion 12 may comprise a fabric or webbing covering or tape 20, which in use, help to mitigate damage and/or heat loss through the edges/seams.

As shown, the closure mechanism 14 is an elongate zipper, provided in a forward side of the upper portion 12. The closure mechanism 14 is provided approximately centrally, at or close to a midline of the upper portion 12 when the heated overshoe 10 is worn. This makes the closure mechanism 14 easily accessible for a wearer.

An elongate flap may be provided over the length of the zipper to better retain heat. The elongate flap may be retained in a closed condition using one or more clips, or buttons or Velcro® for example.

The power pack 17 is connected to the flexible heating layer to power the flexible heating layer.

In the illustrated embodiment, the power pack 17 is of a lithium chemistry type, based on common 18650 packaged cells. The power pack may be provided with a charging and protection circuit to prevent damage due to overcharging or overdischarging. The circuit may also incorporate a timer to provide an auto- shutdown feature. Cylindrical 18650 cells may be preferred as they are resistant to impact damage, are readily available and can provide high power density.

A sensing device to sense operating parameters of the heated overshoe such as temperature, time elapsed, power charge remaining etc may be included. The sensing device may sense ambient conditions and adjust the operation of the flexible heating layer accordingly.

The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.