FR3043314A1 - FOOTWEAR FOR FOOTWEAR - Google Patents

Abstract

A shoe warmer includes a heating element (110), supported by the lower sole layer, comprising a predetermined pattern of heating conductive lines (1121, 1122), the heating conductive lines being circumscribed to a heating zone corresponding to a portion before the sole so as to be under the forefoot. A temperature sensor (152) is arranged on a measurement region (151), separate from the heating zone in the sole, preferably located at the rear of the forefoot, and comprising heating conductor lines configured to obtain a heating similar to that produced by a given region of the pattern of conductive heating lines of the heating zone.

Description

Technical area

The present invention relates to the field of shoes. More particularly, the invention relates to a shoe equipped with a heating soleplate.

State of the art

The sensation of cold feet during the winter period is very unpleasant. To improve the comfort of shoe wearers, heated shoes have been developed.

FR 2 665 815, for example, describes a heating element of simplistic design installed in the sole of a shoe. The heating element comprises a support layer with a rectilinear section comprising two feed lines, which result in a so-called "tip" portion of oval shape. The tip portion constitutes the heating region and supports a heating conductive line pattern describing large meanders extending transversely of the straight section. The opposite end of the rectilinear section is connected to a battery positioned at the heel.

A more recent solution is described in US 2011/0107771. A removable sole includes a heating element positioned on the front portion of the removable sole. The heating zone is comparatively larger than in FR 2,665,815, and especially the heating conductive line pattern is more complex, comprising a plurality of longitudinally and transversely meandering sections connected in series. The heating zone is connected by two conductive strips with two contact pads positioned in the region of the heel, and flush with the underside of the removable soleplate. These contacts cooperate with two contacts positioned in the lower part of the sole, for the supply of the heating element.

The sole of US 2011/0107771 provides a larger heating area than that of FR 2 665 815. The pattern of conductive lines has more narrow meanders extending over a large portion of the heating element, allowing for more intense heating. but locally variable.

Another problem inherent to heating soles is the temperature setting. Closed loop temperature control can be achieved by placing a temperature sensor on the heating element. But this heating zone undergoes heavy mechanical stress, since it is located under the forefoot. There are therefore risks of damage to the temperature sensor and therefore problems of reliability of the temperature control.

Object of the invention

An object of the present invention is to provide a heating insole with improved design and reliable temperature management.

General description of the invention

The present invention relates to a shoe heating sole comprising a heating element having a predetermined pattern of conductive lines, called heating conducting lines, circumscribed to a heating zone corresponding to a front part of the sole so as to be under the forefoot. .

According to the invention, a temperature sensor is arranged on a measurement region, separate from the heating zone in the soleplate, and comprising conductive lines configured to obtain heating / heating similar to that produced by a given region of the pattern of heating conductor lines of the heating zone, which makes it possible to measure a temperature substantially similar to that which would be obtained if this sensor was positioned on the heating zone.

The temperature sensor enables closed-loop control of the heating by means of a control unit associated with the soleplate. It will be appreciated that the temperature sensor is not placed in the heating zone, but is separated from it, positioned on the measuring region, the conductive lines of which thus form heating lines. It is therefore possible to install the temperature sensor set back from the support zone of the forefoot, more or less distantly, which prevents it being damaged by the pressure of the foot when walking. It will therefore advantageously position the measurement region at a location on the soleplate undergoing less mechanical stress than under the support zone of the forefoot, for example in a median or rear region of the sole.

Preferably, the soleplate comprises a feed section, with conductive lines, called feed lines, extending from the heating element towards the median and / or rear zone of the soleplate, for a connection to a heating unit. control, respectively to a power source (in particular rechargeable battery).

In the present invention, a heating conductive line is a conductor whose resistivity and dimensions are chosen to produce controlled heating. On the contrary, a power line is designed mainly to conduct the current and does not have the function of generating a heating. In particular, the supply lines are configured to generate a minimum heating compared to the heating element except at the measurement region.

It is advantageous to position the measurement region in the feed section, which typically extends longitudinally in the sole, for example in the form of a strip / section, rectilinear or otherwise.

The configuration of the feed lines is advantageously locally modified in the measurement region so as to obtain a heating similar to that produced by a given region of the pattern of conductive heating lines. The measurement region thus corresponds to a portion of the feed section. A merit of the invention consists here in having modified locally the configuration of the supply lines, which are not intended to heat, so that they generate the same amount of specific heat as in a given region of the zone of heated.

Preferably, the heating zone is delimited at the rear by a base line, positioned so as to extend substantially transversely to the longitudinal direction of the sole, and towards the front by a shape contour line. globally convex, starting from one side of the baseline following the contour of the toes and joining the opposite side of the baseline (in practice, these baselines and contour may be virtual). The contour line generally joins the opposite ends of the baseline, thus delimiting a closed area of the heating zone. The general shape of the heating zone thus delimited is that of a convex polygon, which is typically close to a triangle or quadrilateral, depending on the model chosen.

The conductive lines have a predetermined resistivity and are, depending on the variants, connected in series or in parallel. The predetermined pattern of heating conductor lines can be achieved by printing techniques, easy to implement with good manufacturing accuracy of the conductive lines. Any other suitable technologies can however be used to make the conductive lines.

A control unit (usually microprocessor) and a rechargeable battery are preferably integrated in the soleplate, particularly in a common sealed housing, or in separate sealed housings. The control unit is designed to regulate heating of the heating element based on the measurement signal delivered by the temperature sensor. Closed-loop regulation is thus possible depending on the measurement signal representative of the temperature at the measurement region.

According to the variants, it is possible to provide an auxiliary temperature sensor installed on the control unit, or close to it in the middle or rear sole portion or in the boot, this auxiliary sensor is connected to the control unit. ordered. In this case, the control unit is designed to regulate the heating of the heating element: - based on the measurement signal of the temperature sensor (52); and / or - based on the measurement signal of the auxiliary sensor (58) and, optionally, the electrical power supplied to the heating element (10). Priority is given to the temperature sensor associated with the measurement region. In case of failure of the latter, the control unit then take will use the measurement signal delivered by the auxiliary temperature sensor for open loop control.

According to one variant, the heating conductive line pattern comprises a first pattern arranged to be directly under the toes and a second pattern attached to the rear of the first pattern, the heating conducting lines of the first pattern being configured to produce a warm-up above the lines. heating conductors of the second pattern. In this case, the measurement region may be designed to obtain a heating comparable to the first pattern of heating conductive lines of the heating element. The measurement region may advantageously be placed on the feed section, and made by local modification of the feed lines.

In general, which heating conductor lines may be configured to describe meanders whose loops extend in one or more directions, particularly in the longitudinal direction of the sole.

According to another variant, the pattern of conductive lines of the heating element comprises a plurality of conducting lines forming similar arcs nested, spaced from each other, the outer arc following the outline of the contour line. In particular, the arcuate conductive lines are nested so that the outer arc constitutes the larger aperture conductive line and the smaller aperture arc constitutes the inner conductive line, the conductive lines being arranged by decreasing aperture size .

A merit of this configuration in arcs is to propose an optimized heating zone in terms of: - position: the heating zone is located under the forefoot, in the region of the toes and towards the junction with the metatarsals, and thus makes it possible to heat the region of the foot that is most sensitive to cold. - dimension: the heating zone advantageously passes as close as possible to the contour of the forefoot, the heating conducting lines are circumscribed to the region of interest, and no energy is lost in regions where the heating is less useful. heating: the shape of the heating conductor lines has been chosen to achieve a high filling rate of the heating zone, which allows heating more uniform and more comfortable for the user than the known solutions.

It will be noted in particular that this configuration allows heating more uniform than that described in US 2011/0107771, which uses heating conductive lines forming meanders in different orientations. The heating element is typically located between a bottom sole layer and an upper sole layer. Preferably, the lower layer is in an insulating material while and the upper layer is in a comparatively good thermal conductor material. An isothermal film, for example of the metallized polyester film type, may be added under the lower layer. The invention can be adapted to any type of sole is preferably an insole, which could possibly be surmounted by a superset in the shoe. This insole can be removable or fixed in the shoe.Next manufacturing technologies, the soleplate can be manufactured by assembling several elements or made in a mold, the heating element, the control circuit, the sensor ( s) temperature, and the battery being placed in the mold and embedded in the sole material or materials. Thus, the term "layer" designates either an element of an assembled sole or a given thickness of a sole molded integrally with the heating components.

In another aspect, the invention relates to a shoe comprising the present heating soleplate.

BRIEF DESCRIPTION OF THE DRAWINGS Other features and features of the invention will become apparent from the detailed description of an advantageous embodiment presented below, by way of illustration, with reference to the accompanying drawings. These show:

Fig. 1: a schematic illustration of an embodiment of the heating sole heating elements according to the invention: a) for left foot, b) for right foot;

Fig. 2: a diagram illustrating the design of the heating element with respect to the morphology of the foot;

Fig. 3: a diagram of the interior arrangement of a soleplate comprising the heating element of FIG. 1; and

Fig. 4: a longitudinal sectional view of the sole of Fig.3;

Fig. 5: a schematic illustration of another embodiment of heating sole heating elements according to the invention: a) for left foot, b) for right foot.

Detailed description of at least one embodiment

Two variants of heating soles comprising heating elements whose patterns of heating conductor lines are different will be described below. In both cases, a temperature sensor is provided, but is not positioned on the heating zone of the heating element. The temperature sensor is separated, in particular off-line on the supply section which is not intended to heat.

An advantageous embodiment of sole heating element according to the invention is illustrated in Figure 1, which has two heating elements 10, the left one (a) being for a left foot sole and the right one (b) for a sole of right foot. In the following, we will speak simply of the heating element 10, because they are designed according to the same principle, even if the shape of the heating element varies according to whether it is intended for a left or right foot. The heating element 10 is intended to be integrated with the sole of a shoe.

As is known, a shoe mainly comprises a sole, the lower part which protects the soles of the feet, more or less raised at the back by the heel, and a upper stem, which surrounds the foot. The stem may be limited to the ankle or rising. The sole (or sole) can be broken down into one or more parts. There is generally an upper sole layer in direct contact with the foot of the user and a lower sole layer in direct contact with the ground or more generally the external environment. The heating element will generally be arranged in an upper sole (or intermediate) to be close to the foot, and in particular in a removable upper sole.

Referring to FIG. 1, the heating element 10 comprises a predetermined pattern of heating conductive lines 12 circumscribed to a heating zone corresponding to a front part of the sole so as to be under the forefoot. Preferably, the heating element 10 is made as an autonomous component, and therefore comprises a support layer 14 of electrically insulating material, on which is arranged the pattern of conductive lines 12 heating. Alternatively, the pattern of heating conductive lines could be made directly on a layer of the sole. Conventionally, the conductive heating lines 12 are designed to produce Joule-controlled heating during current flow. The conductive heating lines are preferably made of a material having a suitable resistivity, in particular of metal or metal alloy. The resistivity of the material of the conductive lines, as well as the cross section of the conductive lines, are adaptable parameters for adjusting the thermal effect. Since the heating is based on the Joule effect, the conductive heating lines 12 may also be called "resistive lines".

In the present heating element 10, the heating zone is advantageously delimited at the rear by a base line 16 (in phantom) positioned so as to extend transversely with respect to the longitudinal direction of the sole (recalled by the A-axis - thus similar to the longitudinal axis of the foot), and forwardly by a contour line 18 of generally convex shape, starting from one side of the baseline 16 following the contour of the toes and joining the opposite side of the baseline 16. In particular, the contour line 18 joins the opposite ends of the baseline 16, thus delimiting a closed surface.

The pattern of conductive lines here comprises a plurality of conductive heating lines 12 forming similar arcs interleaved, spaced from each other, the outer arc following the outline of the contour line. In Figure 1, the conductive lines 12 are shown in white, the support 14 being black. As can be seen, the outermost arc, designated more particularly 12ext, conforms to the black line of the edge that materializes the contour line 18. This is the largest arc, which has the largest opening between its branches and also the largest curvature (we speak here of curvature by excess of language, by analogy with an arc of the circle -the notion will be well understood by the person skilled in the art). From the outer arc 12exi, the next inner arc (direct neighbor) 12i is spaced from the outer arc but exactly follows its shape / curvature. Each inner arc 12j thus follows the curvature of the neighboring arc which surrounds it. A plurality of conductive lines or tracks 12 in the form of interleaved arcs is thus obtained: the outer arc 12ext constitutes the conductive line of greater aperture and the arc of smaller aperture 12jnt constitutes the inner conductive line, the conductive lines being arranged by decreasing aperture size.

It will be understood that the baseline 16 and the contour line 18 are design elements and are therefore generally virtual lines, but may however be represented on the heating element itself. The contour line 16 and the baseline 18 define the extent of the heating zone hosting the pattern of the conductive heating lines 12. The support layer 14 has at least the dimensions of the heating zone, but may be larger. For example in the variant of Figure 1, the edge of the support layer forward coincides with the contour line 18. But towards the rear of the foot (downwards in the figure) the support layer extends to beyond the baseline 16, in particular for the needs of the connectors.

In particular, the reference signs 20 and 22 designate enlarged conductive lines 20 and 22.

In addition, the reference sign 28 designates a strip of the support layer 14, also known as the feed section, extending from the heating zone towards the rear in the direction of the median part of the foot, generally in the longitudinal direction A foot / sole. This band 28 supports conductive lines 24 and 26, said supply lines for supplying current to the heating zone. At one end, the supply lines 24, 26 are thus connected to the expanded conductive lines 20 and 22. At the other end, the supply lines 24, 26 end with connection ends, that is, denotes uncovered ends for connection to a control box, for example by direct contact or by a connector. The strip 28 here forms a rectilinear section, but could have another shape.

It will be appreciated that the reference numeral 52 schematically indicates a temperature sensor positioned on the feed section 28. The temperature sensor 52 is displaced behind the main support point of the forefoot and therefore undergoes fewer stresses and mechanical shock only if it were placed at the level of the heating zone. In order to make a temperature measurement that reflects the heating conditions in the heating zone, although this is not illustrated in FIG. 1, the shape of the conductive strips is locally modified, at a so-called measurement region 51 surrounding the temperature sensor 52, to generate heating similar to that of the heating zone lines. The diagram of Figure 5, relating to another variant, will better understand how this principle of local modification of the configuration of the supply lines in a measurement region can be realized.

In the variant illustrated in FIG. 1, the conductive lines as a whole are connected in series. In particular, the conductive strip 24 is connected to the enlarged track 20, the end of the inner side of the foot is connected to the conductive line forming the outer arc 12ext. The outer side end of the foot of the arc 12ext is connected to the first inner bow 12i, and the inner side end of the foot thereof is connected to the next inner arc. The conductive arcs 12 are thus connected together by their ends so as to form a series circuit. The inner bow 12jnt has its inner side end connected to the previous inner arc, and its outer side end connected to the enlarged track 22 (via a return track 30) which is connected to the feed strip 26. The Heating element 10 according to the invention has an optimized design for heating a shoe. The present arrangement of the conductive lines 12 allows optimum filling of the heating zone, leaving the minimum space required between lines to avoid short circuits and allow the electrical connection. In addition, the distribution of the conductive lines allows uniform heating of the forefoot, for better control and comfort of the user.

The heating zone is sized to heat the desired foot region, primarily the forefoot region. This is why the heating zone has a generally triangular shape. The contour line 18 has a convex shape which follows, possibly with a certain tolerance, the outline of the toes. In the variant (see Fig. 2), the contour line 18 closely matches the front of the toes 2, but there may be some tolerance: the contour line could be +/- 5 mm in front or behind the contour line 18 shown in Fig.2.

The baseline 16 is preferably positioned to correspond to the front portion of the metatarsals, particularly at the junction with the phalanges of the toes. If necessary, this baseline can be moved backwards, but not usually at the level of the arch. Indeed, it is mainly desired to heat the front part of the foot which is most sensitive to cold.

As will be understood by those skilled in the art, the fact that the heating zone has a size adapted to the foot of the user implies to decline the heating element 10 in different sizes, in particular with respect to conventional sizes.

But it is also acceptable to compromise on two or even three sizes. The size of the heating zone can be provided for soles covering two sizes. For example, we can size the heating zone to equip a sole 37/38, 39/40, 41/42, 43/44 or 45/46. In such a case, the sole may be provided to be adjusted to the lower waist by the user, for example by representing a dotted line of cut on one of its faces.

Some remarks on the realization of the heating element 10 still deserve to be made. The pattern of conductive lines 12, with the enlarged lines 20, 22 and conductive strips 24, 26, 54, 56, are preferably made by printing with a conductive ink with a predetermined resistivity, directly on the insulating support 14. use an ink with a copper - nickel alloy. Various printing techniques exist and can be selected at the choice of the skilled person. After printing, an insulating protective layer is applied to the entire printed surface.

The printing techniques allow precise control of the properties of the conductive heating lines, controlling the resistivity of the conductive material and the dimensions of the lines / tracks.

It should be noted, however, that a particular difficulty related to connected shoes is to find a compromise between the various design parameters of a heating element: conductor layout, available electrical power, resistance of the heating circuit.

In consideration of the constraints of autonomy and heating performance, tests have shown that it is desirable for the conductive line circuit 12 to have a total resistivity between 3 and 10 ohms, in particular of the order of 5 to 6 ohms. .

In the case of Figure 1, the conductive lines have a maximum section of a few tenths of mm2, for example 1 mm wide x 0.1 mm high. The space between the arcs of the conductive lines 12 is of the order of 1 mm. This combination of features allows good heating control and reasonable autonomy with a battery delivering between 3 and 5 volts.

In the variant of Figure 5, the sections of the heating lines are wider.

An example of integration of the heating element 10 in a soleplate, indicated 40, is shown in FIGS. 3 and 4. The soleplate 40 is preferably a removable soleplate consisting of a lower layer 42 and an upper layer 44. The heating element 10 rests on the lower layer 42 and is therefore positioned at the front of the foot as explained above. The removable sole, made as an upper sole, is positioned in the shoe above the lower sole in contact with the ground. It can not be excluded, however, that there may still be a bottom sole layer underneath, and / or above another layer of sole.

The section 28 with the feed strips 26, 24 extends centrally along the soleplate to a control unit 46 to which it is connected. The control unit 46 is preferably arranged in a sealed housing 48, which also accommodates a rechargeable battery 50.

Preferably, the lower sole layer 42 is made of a thermal insulating material while and the upper layer 44 is in a comparatively good thermal conductor material, possibly partially perforated. To limit thermal losses to the ground, it is possible to apply under the bottom sole layer 42 an isothermal film (metallized polyester film type). The different materials of the sole are generally flexible.

To facilitate the connection of the heating element 10 to the housing, the ends 24i, 26i of the supply strips 24, 26, on the housing side, are left stripped (not covered), and the housing 48 comprises in its underside flats contact (not shown) connected to the control unit 46 and cooperating with the stripped ends of the strips 24, 26. It is then sufficient to position the housing at the end of the feed section 28 to establish the connection electric. Alternatively, the end of the feed section 28 can be equipped with a connector cooperating with a connector at the housing 48 or the control unit 46. In general, any suitable techniques for connecting and fixing the section supply 28 to the housing 48 may be employed. The control unit 46 placed in the housing 48 comprises for example a microprocessor electronic circuit designed to regulate the heating of the heating element. For this purpose, the temperature sensor 52 is connected to the control unit, for example by means of conductive tracks also provided on the supply section 28, or separate wires. In the example, two conductive strips 54, 56 serve for the electrical connection of the sensor with the control unit.

As can be understood from FIGS. 3 and 4, the housing 48 is typically housed in the middle and / or rear part of the sole 40, and the part comprising the control unit being more particularly arranged in the region of the arch. One can play on cushioning, respectively hardness, materials to improve the comfort of the user and avoid feeling the presence of the housing. The housing 48 is preferably made of a polymeric material, which is better suited to pass telecommunications wavelengths. In addition, the housing 48 is advantageously sealed (waterproof), while allowing the connection to the heating element 10.

The signal delivered by the temperature sensor 52 gives the control unit 46 an indication of the temperature in the heating zone, which allows closed-loop regulation of a set temperature which can be set by design (predefined factory) or preferably fixed by the user. This regulation is preferably carried out directly in the control unit which can then comprise a microcontroller programmed to regulate the temperature in a predetermined manner, taking into account the set temperature and the temperature measured by the sensor 52, so as to adapt the feeding the heating element 10 and thus regulate the heating.

Furthermore, the regulation of the heating of the heating element can be done on the basis of a temperature signal supplied by an auxiliary temperature sensor 58 connected to the control unit, and which can be mounted in the housing 48, or outside thereof away from the heating element in the sole or near the sole edge. In the event of failure of the sensor 52, the auxiliary temperature sensor 58 thus provides an indicative temperature measurement which can be taken into account by the control unit for the temperature control. In particular, the control unit can be programmed to perform the open-loop temperature control, based on the auxiliary temperature sensor signal 58 and the electric power sent to the heating element 10.

It will further be noted that in practice a satisfactory temperature setting can be achieved by using only one of the two temperature sensors 52 or 58. The control unit 46 preferably comprises a communication module with an antenna which enables wireless communication with a communicating terminal. The communicating terminal may for example be a mobile phone (smartphone), a PDA, a tablet, etc.

The link between the control unit and the communicating terminal is via a wireless communication that can be Bluetooth type, allowing a simplified connection, a low power consumption in the communication and a wide range of communicating devices compatible. The communication can be done by other networks such as cellular networks, satellites, WI-FI, or others.

The communicating terminal is programmed to provide a control interface of the heating soles, for programming a set temperature for at least one pair of insoles equipped with the heating element 10, and for example to display the current temperature.

The communicating terminal also makes it possible to retrieve the information identified and / or measured by the insole devices and to store them internally or on a network for a follow-up by the user.

The communicating terminal and a wireless transmitter / receiver module independent of the left sole device and the right sole device makes it possible to connect to the right sole device to adjust the temperature set point and to the left sole device to adjust the same. the set temperature value independently of one another.

Another embodiment of the present heating soleplate will now be described with reference to FIG. 5, which shows only the heating element 110. This heating element may be substituted for the heating element 10 installed in the soleplate 40 of the FIG. 5. Again, the heating element 110 comprises a predetermined pattern of heating conductive lines 112i and 1122 (collectively designated 112) circumscribed to a heating zone corresponding to a front part of the sole so as to be under the front. foot. Carried out as a self-contained component, the heating element 110 comprises a support layer 114 made of electrically insulating material, on which the pattern of heating conductive lines 112 is arranged. Alternatively, the pattern of conductive heating lines 112 could be made directly on a layer of sole (for example the lower layer 42). As in the case of FIG. 1, the heating conducting lines 112 are conventionally designed to produce a Joule-controlled heating during the passage of the current. The conductive heating lines 112 are preferably made of a material having a suitable resistivity, in particular of metal or metal alloy, for example a copper / nickel alloy deposited in the form of printable ink. The resistivity of the material of the conductive lines, as well as the cross section of the conductive lines, are adaptable parameters for adjusting the thermal effect.

The heating zone is advantageously delimited at the rear by a base line 116 (in dotted lines) positioned so as to extend transversely with respect to the longitudinal direction of the sole, and towards the front by a contour line 118 of generally convex shape, starting from one side of the baseline following the contour of the toes and joining the opposite side of the baseline. In particular, the contour line 118 joins the opposite ends of the baseline, thus delimiting a closed surface.

As can be seen in FIG. 5 a), the heating zone comprises a heating pattern composed of two separate patterns. On the frontmost part, a first motif describing narrow meanders. These meanders are all in series thus forming a continuous heating line 112i (or a plurality of lines in series) traversing transversely the heating zone, the loops of the meanders being generally in the longitudinal direction of the sole.

The second pattern is juxtaposed with the first pattern and includes meanders extending in a similar manner, but with a larger width of the conductive heating lines 1122.

Thus, the heating zone is divided in two, the front part being occupied by the first pattern (lines 112i) and the rear part by the second pattern (lines 1122).

The reference sign 128 designates a feed strip which extends into the shoe under the median part of the foot and which here comprises two conductive lines 124, 126, one end of which is connected to the heating lines 112 and the other end is left free, being provided for connection to the control unit 46.

It should be noted that in the variant, to simplify the layout of the heating lines, the supply lines 124, 126 are connected centrally to the lines of the second pattern, and the outer heating lines of the second pattern are connected to the outer heating lines of the first pattern. Thus, all the heating and supply lines are connected in series.

The reference sign 151 indicates a central region of the feed belt, where the layout of the feed lines is changed, and accommodates the temperature sensor 152.

In this region, called measuring region, the supply lines are narrower, to reduce the passage section, and thus increase the resistance and create a heating effect, which is not the nominal function of the supply lines 24, 26. In particular, in the measurement region 151 where the temperature sensor 152 is located, the supply lines are modified in the manner of the layout of the heating lines 112i of the first pattern of the heating zone. Thus the sensor 152 is installed above narrow meanders which will generate a heating similar to that of a corresponding portion of the first pattern, and therefore allow to reach at the sensor 152 a temperature substantially similar to that which would be reached in the sensor if he was positioned on the heating zone.

The positioning of the temperature sensor on the supply section at the measurement zone 151 allows a temperature measurement reflecting the heating at the first heating line pattern 112i of the heating zone, while moving the sensor out of the heating zone. this heating zone which is located under the main point of support of the forefoot.

The measurement region with its associated temperature sensor could be located elsewhere. For example, the feed section could include a lateral protrusion to accommodate the measurement region by deflecting the feed lines. Thus, different possibilities exist to position the measurement region, while avoiding positioning it in the strongest support zones.

FIG. 5a shows diagrammatically the main support zones in which the measuring region with the sensor will not be positioned: the main support zone of the forefoot 160; and - the toe support area 162.

The temperature sensor 52, 152 may be of any suitable type. For example, it is possible to use as a temperature sensor a thermoresistance or thermistor, in particular a Negative Temperature Coefficient (NTC) sensor whose resistance decreases uniformly when the temperature increases and vice versa. Such a CTN sensor allows good measurement accuracy and robustness, for a small footprint. Typically, the temperature sensor may have a thickness between 1 and 2 mm for a diameter of 3 to 5 mm. The sensor 152 is preferably surrounded by a frame or protective ring of rigid material. At the free end of the supply section, two conductive strips are provided for the connection of the temperature sensor 152.

As for the variant of Figure 1, to operate with a battery, the overall resistance of the heating element is preferably of the order of 5 to 6 ohms, measured at the free ends of the strips 124, 126.

In the example shown, the hottest area 112i represents 60% of the resistance. Zone 1122, less hot, represents 30% of the resistance.

This resistance difference illustrates the heat difference between the front and rear portions of the heating zone. The power strip, which is not intended to heat, represents 10% of the resistance of the heating element, with the contribution of the measurement region. Thus, the feed band is a cold zone, with the exception of the feed region.

It will also be noted that in other variants, the measurement region may be designed to be an isolated zone separated from the heating zone and the feed section. The measurement region may be placed in the medial or rear zone of the sole, or elsewhere in the shoe, in regions undergoing more moderate than the support zone of the forefoot.

The measurement region comprises for example a small support with heating conductor lines generating a localized heating comparable to a portion of the same dimension in the heating zone. The measurement region may have a size of the order of 0.5 cm 2 or 1 or 2 cm 2.

Claims (17)

claims A shoe warmer comprising: a heating element (10; 110) comprising a predetermined pattern of heating conductive lines (12; 112i, 1122), the heating conducting lines (12) being circumscribed to a heating zone corresponding to a portion forward sole so as to be under the forefoot; characterized in that a temperature sensor (52; 152) is arranged on a measuring region (51; 151) separated from the heating zone in the soleplate, preferably located at the rear of the forefoot and comprising conductive lines configured to obtain a heating similar to that produced by a given region of the pattern of heating conductive lines of the heating zone. The heating soleplate of claim 1, comprising a feed section (28; 128) comprising conductive lines (24, 26; 124, 26), said feed lines, extending from the heating element to the middle and / or rear zone of the sole, for a connection to a control unit, respectively to a source of electric current. The heating pad according to claim 2, wherein the measuring region corresponds to a portion of the feeding section, wherein the configuration of the feed lines (24,26; 124,26) is locally modified so as to obtain a heating similar to that produced by a given region of the pattern of heating conductive lines (12; 112i, 1122). The heating sole according to any one of the preceding claims, wherein the heating zone is delimited at the rear by a base line (16), positioned to extend substantially transversely to the longitudinal direction of the heating zone. the sole, and forwardly by a contour line (18) of generally convex shape, starting from one side of the baseline following the contour of the toes and joining the opposite side of the baseline. The heating pad according to claim 4, wherein the contour line (18) joins the opposite ends of the baseline (16), thereby delimiting a closed area of the heating zone having a generally triangular shape. The heating sole according to any of the preceding claims, comprising a control unit (46) and a rechargeable battery (50) integrated into the soleplate, preferably in a sealed housing (48). The heating pad according to claim 6, wherein the control unit (46) is adapted to regulate the heating of the heating element (10) based on the measurement signal delivered by the temperature sensor (52, 152). . The insole according to claim 7, wherein an auxiliary temperature sensor (58) is installed on or near the control unit (46) in the middle or rear sole portion (40), and said auxiliary sensor (58) is connected to the control unit; and the control unit (46) is adapted to regulate the heating of the heating element (10): - on the basis of the measurement signal of the temperature sensor (52); and / or - based on the measurement signal of the auxiliary sensor (58) and, optionally, the electrical power supplied to the heating element (10). The heating sole according to any one of claims 1 to 8, wherein the pattern of heating conductive lines comprises a first pattern disposed to be directly under the toes; and a second pattern attached to the back of the first pattern, the heating conductive lines (112i) of the first pattern being configured to produce a higher temperature than the conductive heating lines (1122) of the second pattern. 10. An insole according to claim 9, wherein the feed lines (124, 26) are modified at the measurement region (151) so as to generate a heating comparable to the first pattern of heating conductive lines (1120). the heating element. The heating soleplate according to claim 4 or any one of claims 5 to 8 depending on 4, wherein the pattern of heating conductive lines (12) of the heating element comprises a plurality of interleaved similar arcuate conductive lines, spaced from each other, the outer arc (12ext) following the outline of the contour line (18). 12. An insole according to claim 11, wherein the arcuate conductive lines (12) are interleaved so that said outer arc (12ext) constitutes the larger opening conductive line and the smaller aperture arc (12int) constitutes the inner conductive line, the conductive lines being arranged by decreasing aperture size. The heating pad according to any one of the preceding claims, wherein the supply lines are configured to generate minimum heating compared to the heating element except at the measurement region. The heating pad according to any of the preceding claims, wherein the heating element (10, 110) is located between a bottom sole layer (42) and an upper sole layer (44), and preferably, the bottom layer is in an insulating material while and the top layer is in a comparatively good thermal conductor material. A shoe comprising a heating soleplate (10) according to any one of claims 1 to 14, a control unit and a power source, in particular a battery, the feed lines of the feed section being connected to the power supply. control unit, the temperature sensor being also connected to the control unit (46), and the control unit being adapted to regulate the heating of the heating element (10) on the basis of the measurement signal delivered by the temperature sensor (52, 152). The shoe of claim 15, wherein an auxiliary temperature sensor (58) is installed on or near the control unit (46) in the back sole (40) or in the shoe. , and said auxiliary sensor (58) is connected to the control unit. Shoe according to claim 16, wherein the control unit (46) is adapted to regulate the heating of the heating element (10): - on the basis of the measurement signal of the temperature sensor (52); and / or - based on the measurement signal of the auxiliary sensor (58) and, optionally, the electrical power supplied to the heating element (10).