VAPORIZATION CHAMBER FOR A HAIRSTYLING APPLIANCE THAT DIFFUSES STEAM

[0001]The present invention relates to a vaporization chamber, in particular for a hairstyling appliance that diffuses steam and is intended to shape or style a head of hair. The appliance is more particularly a hair brush that is able to diffuse steam over the hair.

[0002]Numerous types of household electrical hairstyling appliances for shaping a head of hair, in particular by straightening, curling or crimping, are known. Straightening or curling irons or hair brushes may be mentioned by way of example. These appliances may comprise one or more heated or heating treatment surfaces. The general design of such appliances is well known.

[0003]In order to improve the treatment, some appliances have, for some time, dispensed steam towards the surface to be treated, in particular a lock of hair or the whole head of hair in the case of hairstyling appliances.

[0004]Thus, the document U.S. Pat. No. 2,880,299A, for example, describes a curling iron that is able to dispense steam onto a lock of hair gripped between two articulated arms and wound around said arms. The steam is generated directly from the reservoir containing the liquid water, this therefore also serving as a vaporization chamber. The document EP3097815 implements a similar system, which differs in that the reservoir has been shifted away from the portable treatment unit in order for it to be possible to increase the capacity thereof.

[0005]For their part, the documents US20040000319A1 and US2009188516A1 describe appliances of the straightening iron type that are also able to dispense steam onto a lock gripped between two arms that are each equipped with a heating plate. In the document US2004000319, the liquid water contained in a reservoir is brought into contact with an evaporation plate via a porous pad. In the document US2009188516, the steam is generated in a steam generator away from the treatment unit and not described in detail.

[0006]Lastly, brushes and combs, heated or non-heated, which are able to dispense steam through a head of hair while they are being used may also be mentioned. Reference could be made to the documents KR20030085159A and DE19822718A1, by way of example. These documents provide little detail with regard to the way in which the steam is generated.

[0007]However, several appliances are known in which the steam is generated by a steam generator that consists substantially of a chamber fed with liquid water from a separate reservoir, which is heated to a high enough temperature to cause it to evaporate. Such a system makes it possible to optimize and better control both the flow rate of steam dispensed and the energy consumed for vaporization.

[0008]The steam thus generated is then brought into or close to the treatment surface where it is dispensed through one or more nozzles. For a precise description of such steam generators, reference could beneficially be made to the documents U.S. Pat. Nos. 3,934,597, 3,921,648, WO2017174035A1, WO2017089582A1, WO2020127851A1 and WO2020127852A1, inter alia.

[0009]A problem shared by the appliances implementing a steam treatment is the scaling up of their steam generator. This scaling up can result in the inlet orifice for liquid water and/or the steam outlet orifices being obstructed.

[0010]Moreover, unlike an appliance of the clothes iron type, in the case of which it may be acceptable for a certain quantity of scale to reach the steam dispensing orifices, this would not be desirable in the case of a hair treatment appliance. In any case, the steam flow rate of these appliances is much lower (between 0.5 and 5 g.min⁻¹ and in particular less than 1 g.min⁻¹ for recent appliances that are particularly compact and incorporate all the elements in a single portable unit) and insufficient to drive out the scale that reaches the diffusion orifices.

[0011]The particles of scale therefore have to be retained in the vaporization chamber. This is achieved conventionally by equipping the vaporization chamber with one or more chicanes that are disposed, preferably, at a distance from the inlet for liquid water, as described in the document EP2449909A1. Thus, the chicanes make it possible both to prevent the circulation of liquid water that has not yet been vaporized to the steam outlet orifices and to retain the particles of scale that form at the inlet for liquid water.

[0012]Various solutions exist for slowing or reducing the accumulation of scale at the inlet for liquid water in such appliances.

[0013]A first solution is to use distilled or demineralized water. However, this is not very practical and users generally prefer to be able to directly use tap water.

[0014]A second solution is to install a limescale filtration system between the reservoir and the steam generator. However, such a solution is difficult to envisage in “all in one” portable appliances that have only extremely limited space for accommodating all the components. Moreover, the presence of such a filter brings about pressure drops that may have a negative impact on the pumping members intended to convey the liquid water from the reservoir to the vaporization chamber.

[0015]Yet another solution is to make the vaporization chamber removable in order for it to be possible for it to be cleaned. As before, this is difficult to implement in an “all in one” appliance for household use. Furthermore, the vaporization chamber is a sensitive component and it would be appropriate for it to be able to be removed and refitted by the user completely safely.

[0016]The document WO2017089582 provides a solution to the problem of scaling up by providing an inclined vaporization element, allowing the particles of scale and other particles to fall off the vaporization element in order to be collected. Besides the abovementioned problem of incorporating a collector in an appliance that needs to be particularly compact, a hair treatment appliance, such as an iron or a brush, is handled in such a way as to make it likely to be located in any direction. Thus, the idea of an inclined wall and the falling off of the particles loses its appeal.

[0017]The document WO2020127851 provides covering an internal surface of the vaporization chamber, at least partially, with a hydrophobic layer, said layer being at least positioned beneath the injection point of liquid water. The presence of the hydrophobic layer beneath the injection point will avoid any vaporization of this liquid at this specific location, since it is repelled further on. Although effective, this solution makes it more complex and more expensive to manufacture the chamber.

[0018]Alternatively or in addition, the document WO2020127852, for its part, provides an inlet pipe for liquid water in the vaporization chamber, which has an opening extending substantially along the injection pipe from a free end forming an injection point, the opening having a shape allowing the liquid coming from the reservoir to flow into the vaporization chamber in the case of accumulation and deposition of scale at the free end of the injection pipe. Such a solution does not make it necessary to modify the basic design of the vaporization chamber. However, in the case of accumulation of scale at the end, the liquid water then has to accumulate in a sufficient quantity to pass the level of obstruction. It has also been noted that, in the case of a vaporization chamber heated to a high temperature (for example greater than or equal to 180° C.), such a design would not allow optimal distribution of the limescale, the vaporization taking place very rapidly and in a very localized manner.

[0019]The present application aims to propose an alternative or complementary solution to some of these systems, making it possible to deal with their limitations.

[0020]To this end, the present application relates to a vaporization chamber comprising a hollow body defining a free interior space that is able to allow fluid circulation between at least one inlet for feeding a liquid product to be vaporized and at least one outlet for said at least partially vaporized product.

[0021]According to the invention, the steam chamber is characterized in that the inlet or inlets for feeding liquid product have, together, a plurality of orifices that open into the interior of the vaporization chamber and are spaced apart from one another. The orifices are spaced apart from one another by at least 5 mm, preferably at least 8 mm, or even at least 10 mm.

[0022]Thus, by providing a plurality of separate and spaced-apart orifices for introducing liquid water inside the vaporization chamber, the risk of obstruction of the feed of liquid water is greatly reduced. Specifically, when an orifice is scaled up so far as to be clogged, it is still possible for the liquid water to pass through the other available orifice or orifices. This also allows better distribution of the scale, the liquid water being vaporized in the chamber at different locations and no longer at a virtually single location. This naturally results in better distribution inside the chamber of the scale formed by the evaporation, and consequently a risk of complete obstruction arising at a later time.

[0023]Furthermore, this affects the design of the vaporization chamber only a little or in a way that is relatively simple to implement, since no additional parts or additional coating is necessary.

[0024]Preferably, the product to be vaporized is water, in particular water that is not demineralized, not distilled and not filtered. Preferably, the water used has a hardness (degree of hardness) greater than 8° F., preferably greater than 15° F. Preferably, the water used has a hardness less than or equal to 30° F. If necessary, the water used could optionally be softened so as to reduce its hardness between 15 and 30° F., preferably between 15 and 20° F.

[0025]The number of orifices that are provided could advantageously be greater than three, and in particular be between three and ten orifices.

[0026]The orifices could each have a section that is substantially circular but also preferably oval.

[0027]The orifices could each have a section of between 0.1 and 6 mm².

[0028]According to a first embodiment, the inlet for feeding liquid product is in the form of a pipe having a terminal part which extends inside said vaporization chamber and along which a plurality of orifices are provided in a spaced-apart manner. In particular, the feed inlet is made up of a single pipe.

[0029]Although the document WO2017174035A1 provides an inlet for liquid water in the form of a tube 1125 having a plurality of feed orifices 1140 that open out on either side of the tube, it should be noted that the vaporization chamber does not define a free space as per the present application but contains a porous material 1126 occupying said interior volume. In accordance with the present application, the vaporization chamber has, at least, a free space that does not have porous material around the orifices for feeding liquid water (distance of at least 2 mm, or 5 mm, better still 10 mm from the orifices for feeding liquid water). The free space in particular allows the liquid water leaving an orifice to arrive directly in contact with the at least one evaporation surface of the chamber. Preferably, the vaporization chamber is entirely without porous material.

[0030]Preferably, the orifices are spaced apart regularly. In particular, the orifices could be provided every 5 mm along the pipe. The terminal part of the pipe extending inside the vaporization chamber could conventionally be between 20 and 60 mm, typically around 39-40 mm.

[0031]Advantageously, the orifices are distributed substantially along the entire length of the terminal part of the pipe forming the feed inlet.

[0032]Preferably, the terminal part of the pipe forming the feed inlet has a closed distal end.

[0033]According to a preferred embodiment variant, the orifices are provided along at least two longitudinal axes of the pipe that form, between one another, a non-zero angular sector with a longitudinal central axis of the pipe. In other words, the orifices are provided in an offset manner along the pipe. Preferably, the angular sector is substantially equal to 180°, meaning that the orifices are disposed along longitudinal axes situated on either side of a central longitudinal axis of the pipe and in a diametrically opposed manner with respect to this central longitudinal axis.

[0034]Preferably, the orifices are provided along the two longitudinal axes, at least in the case of some of them, and preferably all of them, in an alternating manner.

[0035]According to a second embodiment, the vaporization chamber comprises a plurality of inlets for feeding liquid product to be vaporized, each feed inlet having at least one orifice opening into the interior of the vaporization chamber.

[0036]According to a first variant, at least one inlet for feeding liquid product to be vaporized has a single orifice opening into the interior of said vaporization chamber. Preferably, the orifice is in the form of an open distal end of the inlet for feeding liquid product to be vaporized. This open distal end may be bevelled or be cut lengthwise as described in the document WO2020127852 cited above.

[0037]Preferably, all the feed inlets each have a single opening orifice. Alternatively, at least one inlet may be a pipe according to the first embodiment.

[0038]According to one particular embodiment, at least some of the orifices that open into the interior of the vaporization chamber, preferably all of the orifices, open at a non-zero distance from internal surfaces of the body forming said vaporization chamber, these internal surfaces comprising the surfaces of peripheral walls and, as the case may be, the surfaces of interior chicanes.

[0039]The present application also relates to a household domestic appliance that diffuses steam, comprising at least one reservoir that is able to contain a quantity of a liquid product to be vaporized and is fluidically connected to at least one inlet for feeding liquid product to a vaporization chamber that is separate from the reservoir, said vaporization chamber having at least one outlet for at least partially vaporized product, which is fluidically connected to steam diffusion orifices of a treatment surface of the appliance. According to the present application, the appliance is characterized in that the vaporization chamber is a chamber according to the invention as mentioned above.

[0040]The term household electrical is understood to mean appliances and tools that use electricity and are intended to be used for domestic purposes.

[0041]Preferably, the product to be vaporized is water, in particular water that is not demineralized, not distilled and not filtered. In particular, the water used has a hardness (degree of hardness) greater than 8° F., preferably greater than 15° F. Preferably, the water used has a hardness less than or equal to 30° F. If necessary, the water used could optionally be softened so as to reduce its hardness between 15 and 30° F., preferably between 15 and 20° F.

[0042]Advantageously in addition, the vaporization chamber is able to be fed with liquid product contained in the reservoir via at least one active pumping member. Preferably, the pumping member is an electric member, and in particular a positive displacement pump, for example a peristaltic pump or a membrane pump.

[0043]In the case of a vaporization chamber comprising several inlets for liquid water, the feed from the reservoir could take place via dedicated pipes. However, it will be possible to use a pipe comprising one or more forks so as to keep a reservoir having a single outlet and a single pumping member delivering the water towards several branches that are each connected to a liquid water inlet of the vaporization chamber. However, it should be noted that such a fork is liable to create bursts or irregularities in the feed of liquid water, and a solution employing pipes and dedicated pumping members will be preferred. In addition, the feed pipes or their branches downstream of a fork could be equipped with non-return valves.

[0044]Preferably, the appliance is a hairstyling appliance such as a straightening iron or a hair brush

[0045]The term “brush” means a device for treating the hair comprising a single arm bearing a plurality of teeth between which the hair is received as the brush passes through the head of hair. The brush may have a single row of teeth, in which case it is also called a comb, or has a plurality of rows of teeth. The brush may comprise a heating treatment surface. The teeth may or may not also actively heat up.

[0046]A “straightening iron” means a hair treatment device having two arms that are articulated with respect to one another about a hinge between an open configuration and a closed configuration. At least one arm, and preferably each arm, is equipped with a treatment surface in the form of a heating plate. During operations for treating a lock of hair, the latter is introduced between the two arms in the open position and then the two arms are closed manually over the lock of hair. The latter is then subjected, until the two arms are opened and the lock of hair is removed, to the heat output by the heating element, the appliance being able to be moved along the lock.

[0047]Advantageously, the vapour chamber, and preferably the reservoir, are incorporated in a portable treatment unit of the appliance. In particular, the reservoir could be incorporated in a handle thereof, and the vaporization chamber could preferably be situated in the immediate vicinity of a treatment surface of the appliance so as to minimize the vapour path from the vaporization chamber to the diffusion nozzles. The pumping member may of course also be incorporated in the handle.

[0048]Advantageously, the vaporization chamber is configured to be able to reach a temperature greater than or equal to 180° C.

[0049]Further aims, features and advantages of the invention will become apparent from reading the following description, which is given only by way of non-limiting example and with reference to the appended drawings, in which:

[0050]FIG. 1 is a schematic depiction in longitudinal section of a hair brush that is able to apply steam to the hair.

[0051]FIG. 2 is a schematic depiction in longitudinal section of the treatment part of the hair brush in [FIG. 1], showing the vaporization chamber.

[0052]FIG. 3 is a schematic depiction of a vaporization chamber in accordance with the present application and according to a first embodiment.

[0053]FIG. 4 is a schematic depiction of the distribution of the scaling up of the vaporization chamber in [FIG. 3] over time.

[0054]FIG. 5 is a schematic depiction of a vaporization chamber in accordance with the present application and according to a second embodiment.

[0055]FIG. 1 is a schematic depiction in longitudinal section of a hair brush 100 that is able to dispense steam onto the hair.

[0056]Although illustrated by way of example as a hair brush, the present application may also relate to other household electrical appliances that dispense water vapour, and in particular other household electrical hair treatment appliances that are able to dispense water vapour onto the hair. An example of another appliance is a straightening iron as described in particular in the document FR2967018A1.

[0057]The hair brush 100 has a gripping handle 110 and a treatment head 120. The head 120 has a set of teeth 121 arranged on a support plate 122 along a plurality of rows. The rows of teeth 121 extend substantially along a longitudinal axis X of the brush.

[0058]In the example shown, the support plate 122 is substantially flat and has a substantially rectangular shape extending in the continuation of the gripping handle 122. It is of course conceivable to have a curved support plate, the teeth 121 then being preferably situated on a concave surface of the support plate, or even a substantially cylindrical support plate.

[0059]In one particular embodiment, the support plate 122 and/or the teeth 121 may heat up. Preferably, only the teeth 121, or only some of the teeth 121, heat up.

[0060]The head 120 also has a plurality of steam outlets 130 that open onto the support plate 122. The steam outlets or nozzles 130 may be situated between teeth 121 in one or more rows or be separate and in particular arranged along an edge of the support plate 122.

[0061]Alternatively, the steam outlets 130 may be made in the teeth 121, and in particular open onto a side of the latter.

[0062]According to the embodiment shown, the steam nozzles 130 open out between the teeth 121 of one and the same row, in this case between the teeth of a middle row, thus forming a row of steam outlets 130 extending substantially in the continuation of the handle 110.

[0063]The steam is conveyed to the steam outlets from a vaporization chamber 350 incorporated in the appliance 100, through one or more diffusion channels passing through the support plate 122, and the teeth 121 where applicable. According to the example shown, the vaporization chamber 350 is incorporated in the head 120 behind the support plate 122. Such elements are well known to those skilled in the art.

[0064]In a general manner, the vaporization chamber 350 comprises a hollow body forming an enclosure and defining a free interior volume, that is to say one that is not occupied with any filling material and in particular does not have an absorbent element, which is able to allow fluid circulation between at least one inlet for feeding liquid water to be vaporized and at least one outlet for the water in the form of steam.

[0065]The volume of the vaporization chamber is preferably from 20 to 100 cm³, better still from 30 to 70 cm³, for example around 45 cm³.

[0066]The reservoir may have a volume of between 1 mL and 50 mL.

[0067]To this end, the vaporization chamber 350, and in particular a part with which the liquid water is intended to come into contact in order to be vaporized, is able to be heated to a sufficient temperature, in particular by a heating resistive element in contact with a wall of said chamber. More particularly, the heating temperature is greater than 180° C. The heating resistive element may be shared between the vaporization chamber and a heating treatment surface of the household electrical appliance if necessary. The heating elements may also be separate, in particular so as to be able to be controlled independently.

[0068]The vaporization chamber 350 also comprises one or more interior walls that together form chicanes 351 between the inlet for liquid water and the outlet for water in the form of steam. In particular, the chicanes are situated in the vicinity of the outlet for water in the form of steam. Thus, preferably, the vaporization chamber has less than 50%, preferably around 25%, of its interior space provided with chicanes, and more than 50%, preferably around 75%, of its interior space without chicanes, liquid water being fed in the zone without chicanes.

[0069]The steam outlet is generally in the form of one or more orifices, in particular in the form of a groove or slot made in an upper wall of the vaporization chamber, said upper wall forming a cover for closing and sealing the vaporization chamber.

[0070]The vaporization chamber is fed with liquid water from a reservoir 300 by a positive displacement pump 200, for example a peristaltic pump or a membrane pump. The reservoir 300 is incorporated in the device made up of the hair brush 100, in particular in its handle 110. It may advantageously be removable so that it can be replaced easily. Otherwise, a filling hole 301 may be provided in a wall of the handle 110. The filling hole 301 could be equipped with a valve for preventing liquid from leaking out of the reservoir 300. The pump is also incorporated in the handle of the device.

[0071]Preferably, the device is configured to feed the vaporization chamber with liquid water so as to achieve a steam diffusion flow rate greater than or equal to 0.5 g.min⁻¹ and less than or equal to 5 g.min⁻¹. Preferably, the steam diffusion flow rate is less than or equal to 1 g.min⁻¹, preferably around 0.8 g.min⁻¹.

[0072]In accordance with the present application, the inlet or inlets for feeding liquid product have, together, a plurality of orifices that open into the interior of the vaporization chamber and are spaced apart from one another.

[0073]A first exemplary embodiment of such a vaporization chamber 400 is partially shown in [FIG. 3].

[0074]According to this embodiment, the vaporization chamber 400 comprises an inlet for feeding liquid water, in the form of a single pipe or tube 401 passing through a wall 402, in this case over the width, of the vaporization chamber 400 and having a terminal part 403 which extends inside said vaporization chamber 400, and more particularly inside the zone without chicanes.

[0075]More particularly, this tube 401 extends over at least half, better still over around 80% of the distance separating the wall 402 through which it passes and an opposite wall 404 of the vaporization chamber 400. More particularly, the vaporization chamber 400 is configured such that this separating distance corresponds substantially to its length.

[0076]In accordance with the present application, the terminal part 403 of the tube 401 for feeding liquid water has a plurality of orifices 405 that are spaced apart from one another and provided along said terminal portion 403, in particular along substantially the entire length of the terminal part 403 extending in the vaporization chamber 400. The orifices 405 are spaced apart regularly. There are eight orifices.

[0077]According to the embodiment variant shown, the terminal part 403 of the tube 401 forming the feed inlet has a closed distal end 406. Thus, the only openings for dispensing liquid water are the lateral orifices 405 provided along the tube.

[0078]As shown in [FIG. 4], the orifices may be provided in an alternating manner on either side of a longitudinal axis of said terminal portion 403. In this way, the distribution of the flow of liquid water, and consequently of the scale that forms during evaporation, is optimal.

[0079]A second exemplary embodiment of such a vaporization chamber 500 is shown in [FIG. 5].

[0080]According to this embodiment, the vaporization chamber 500 comprises a plurality of inlets for feeding liquid water that are distributed, preferably regularly, along a wall 503 of the chamber, this wall extending preferably in the direction of the length of said chamber 500.

[0081]The feed inlets are, as previously, disposed so as to open into a zone without chicanes of the vaporization chamber.

[0082]Each feed inlet is in the form of a pipe or tube 501 having a terminal part that extends inside said vaporization chamber 500 and is open at its end. The tube does not have additional lateral orifices as in the first embodiment. As indicated above, the open end of each tube 501 is cut lengthwise, as described in the document WO2020127852.

[0083]Of course, according to one embodiment variant, one or more of the tubes forming feed inlets according to the second embodiment may be made in the form of a tube according to the first embodiment comprising a plurality of lateral orifices and having preferably a closed distal end.

[0084]Generally, it should be noted that the orifices for dispensing liquid water inside the vaporization chamber open at a distance from internal surfaces of the body forming said vaporization chamber, these internal surfaces comprising the surfaces of peripheral walls and, as the case may be, the surfaces of interior chicanes. In particular, each orifice opens at least 1 mm from a wall of the vaporization chamber, in particular with respect to a bottom wall and an opposite upper wall. With respect to lateral walls and the interior chicanes of the chamber, the distance for each orifice could instead reach at least 10 mm.