EP0433523A1

EP0433523A1 - Electrically heated shoe insole

Info

Publication number: EP0433523A1
Application number: EP89830561A
Authority: EP
Inventors: Luciano Bracaccini
Original assignee: ELI-MAR - Srl
Current assignee: ELI-MAR - Srl
Priority date: 1989-12-21
Filing date: 1989-12-21
Publication date: 1991-06-26

Abstract

The instrument is produced with various components available on the market, duly modified and shaped as required. The same consists of a shoe insole with an incorporated electric heating element - connected to a battery - for heating the insole and consequently the sole of the foot of the user.

Description

This patent application for an industrial utility model concerns a plush shoe insole, heated by means of an internal electric heating element.
This item was developed in order to improve the comfort of heavy shoes and, above all to keep the wearer's foot warm and dry in the shoe even at very low temperatures and/or particularly humid conditions.
It is common knowledge that feet are very sensitive to cold and humid conditions, and that allowing feet to remain for a long period of time in these difficult conditions may create even very serious cooling of the entire body. The heated insoles in question are very practical and efficient in this respect in that once fitted into the shoe, they provide a immediate and uniform warmth to the sole of the foot; they are especially functional in that just as they can be fitted in the shoe when necessary, they can also easily be removed when warmer conditions eliminate the need for artificial warming of the foot sole.
The ideal potential users of these heated insoles are therefore all those who for reasons of work, related requirements or even for pleasure, have to spend long periods of time outdoors in difficult weather conditions. The basic concept of this invention consists in developing a plush insole, or alternatively made of similar material, in which an electric heating element is "buried", the same being in turn connected by means of a thin electric wire, to a power supply battery capable of transmitting the current required for heating.
This battery must obviously be positioned on the user's body, who, after having fitted the heating insoles inside his shoes, must hook the power supply battery to his body by means of special attachments.
Two versions of this invention have been developed which are different in terms of construction but based on the same concept: a first version whereby the heating elements fitted in the pair of heating insoles are supplied by two batteries supported by special belts, to the calves of the wearer, and a second version whereby only one battery is used, hooked to the belt of the user and fitted with two separate wires each of which supplies power to one of the two heating elements of the pair of insoles.
For major clarity the description of the invention continues with reference to the enclosed drawings which are intended only for illustrative purposes and not in a limiting sense, where:

-: table 1 is a view and a prospective diagram of the first version of the invention, that is, in which each heating insole is supplied by its own battery;
-: table 2 is a view of the second version of the invention, where both heating insoles are supplied by a single battery.

In the first version, the product according to the invention shall have the general schematic form of table 1, with the following characteristics:

heating element with 0.20 mm copper wires per 32 lm, 12 volt accumulator, 25 ehm heating element, absorbed current 0.48 Amp 5.76W, heat produced 4.95 Kcal/h.

All the components are protected by plush insulation, or a similar material, in the sizes according to the shoe insole.
The following are required:

A= double plush insole, one under detail B and the other above: different sizes;
B= 0.20 mm copper heating element (32.00 lm)
C = soldering with tin between wires and heating element or rivets;
D= double plush protection of cables, as per detail A;
E= copper wire having a suitable cross-section;
F= connection plugs between battery and wires;
G= 12 volt battery;
H= leather belt with fixing buckle: different sizes.
I= main ON/OFF switch.

The second table illustrates the second version of the invention characterized by several construction differences with respect to the above version.
Above all, it should be noted that while in the case of the version in table 1, the electric wire (E) is connected to the heating element (B) on the heel of the insole (A), in the second version illustrated in table 2, the wire (E) is connected to the heating element (B) on the side of the insole (A), at the internal central area of the foot: that is, in a position whereby the wire may be fitted into the shoe with no inconvenience whatsoever to the user: it should be noted that these solutions can be considered as alternative and interchangeable versions.
In fact, as mentioned above, the significant construction difference between the two different models of the invention, consists of the fact that in the version in table 2, both the insoles (A) are supplied by a single battery (G) - fixed possibly to the belt of the user by means of a standard hooking device - from which two separate wires (E) are subdivided, each of which connects to one of the two electric heating elements (B) buried in the plush insole (A).
It should be noted in this regard that the battery (G) used in this second version of the device in question is fitted with a plug for recharging and an ON/OFF switch (1). Obviously in the case of two separate batteries, these will be fixed to the calves of the user and connected to the insoles by means of two short wires while in the second version since a single battery is fixed to the belt of the user, two longer wires will be required for supplying the current from the waist to the foot.
In both cases however, these wires may easily be passed inside the trousers of the user so as to hide then and above all in order to prevent them from becoming tangled and perhaps even pulling them out of place while the user is moving.
Obviously the object of this patent application may be produced in any shape and size for adapting to any type or style of men's, ladies' or children's shoes.

Claims

An electrically heated shoe insole characterized in that the same is produced with a double layer of plush or similar material, in which an electrical heating element (B) is "buried" and connected by means of a wire (E) to a battery (G) capable of transmitting the power required for heating the insole in that this heating element (G) must produce enough heat to warm the entire surface of the insole (A) efficiently and uniformly.
An electrically heated shoe insole according to claim 1, characterized in a preferred embodiment in that the heating element of each insole (A) is supplied by its own battery (G).
An electrically heated shoe insole according to claim 1 characterized in a second preferred embodiment in that the two heating elements (B) buried in a pair of insoles (A) are supplied by a single battery (G) by means of suitable wires (E).