Technical Field

The present disclosure relates to a hair styling apparatus for applying a fluid flow to a user’s hair to form the hair into a desired shape.

Background

Hair styling apparatuses, such as hair straightening devices, curlers, heated brushes, and hair dryers, can be used to form hair into a desired shape or style. Typically, such devices achieve this styling by application of heat to a user’s hair. This breaks chemical bonds in the hair, which allows the hair to be reshaped (i.e. into a shape other than its natural shape). The heat required to break these bonds is commonly provided by hot plates.

For example, a typical hair straightening device includes two hingedly connected arms, with each arm including a hot plate that faces the hot plate of the other arm. The arms can be moved between an open position in which a tress of hair can be received between the hot plates and a closed position in which the hair is clamped between the hot plates. A user can then move the device along the tress of hair to straighten the tress of hair.

The hot plates rely on conduction to provide heat to a tress of hair. However, because hair is an insulator, heat transfer to the centre of a tress of hair is not particularly efficient. To ensure that heat is transferred to the centre of the tress of hair it is necessary to operate the hot plates at high temperatures (e.g. above 150°C). If not managed correctly, these high temperatures can result in heat damage to a user’s hair.

An alternative to providing heat via hot plates is to use steam or hot air to apply heat to a user’s hair. Steam, for example, relies on convection to transfer heat to the tress of hair, which is better at ensuring uniform heat application than conduction. This means steam, which is at a lower temperature than a typical hot plate, can provide the same effect as (and in some cases a better effect than) a hot plate.

Regardless of whether heat is applied via hot plates or a fluid (such as hot air or steam), there is a general desire to increase the styling performance of such apparatuses. This may be in the form of, for example, increased versatility (e.g. ability to create a larger variety of styles), increased smoothness (i.e. with fewer “fly-aways”) or increased hair drying ability.

The present disclosure has been devised in light of the above considerations. Summary

In a first aspect, there is provided a hair styling apparatus for styling a tress of hair, the apparatus comprising: first and second elongate arms, each arm comprising opposing inner and outer surfaces, the inner surfaces defining a hair-receiving space therebetween; an internal fluid outlet arranged on one of the inner surfaces to discharge a fluid into the hair-receiving space; and an external fluid outlet arranged on one of the outer surfaces to discharge a fluid externally of the hair-receiving space.

The provision of both internal and external outlets can provide the apparatus with increased versatility (e.g. it may increase the number of ways in which the apparatus can be used). For example, the provision of the internal outlets allows the apparatus to be according to a first use type in which a tress of hair is received between the arms and the apparatus is moved along the tress of hair (to apply the fluid along the length of the tress). The provision of external outlets (depending on their configuration) may facilitate a further second use type in which a tress of hair is wrapped about the arms and fluid is directed onto the hair via the external fluid outlets. Thus, for example, a user is provided with the ability to wrap a tress of hair about the arms to perform one type of styling action or to pass a tress of hair through the hair-receiving space to perform another type of styling action. Accordingly, the apparatus may be used in at least two ways, which may allow a user to achieve a greater range of styles.

The provision of both internal and external outlets may also improve the styling performance of the apparatus. For example, and as will be discussed further below, in the first used type discussed above, the external outlets may direct fluid flow onto the tress of hair (e.g. a portion of the tress forward or behind of the arms) which may provide performance benefits (e.g. may increase the volume of fluid directed onto the tress and/or may reduce “fly-aways” to create a smoother appearance).

Optional features will now be set out. These are applicable singly or in any combination with any aspect.

The arms may be movably mounted to one another so as to be moveable between an open position in which a tress of hair can be received in the hair-receiving space, and closed position in which the tress of hair can be clamped between the inner surfaces. The arms may be pivotably connected. Each arm may extend from a proximal end, at which it is pivotably connected to the other arm, to a distal (free) end.

The hair-receiving space may comprise opposed leading and trailing openings for receipt of a tress of hair therethrough. The leading opening may lead in movement of the apparatus along a tress of hair in normal use. The trailing opening may trail in movement of the apparatus along a tress of hair in normal use.

Accordingly, the apparatus may comprise a leading portion that leads in movement of the apparatus along a tress of hair in normal use, and a trailing portion that trails in movement of the apparatus along a tress of hair.

Hence, in normal use, the apparatus may move along a movement axis that extends in a direction between the leading and trailing portions (and likewise, between the leading and trailing openings).

For the avoidance of doubt, this is not intended to require that the leading opening always (or only) leads in movement and the trailing opening always trails in movement in use of the apparatus. For example, in some embodiments the apparatus may be configured for movement along a tress of hair in two directions (i.e. may be configured for bi-directional movement). In other words, in such embodiments the apparatus may not necessarily be configured for movement along a tress of hair in a particular direction and in such cases each opening could be the leading or trailing opening (depending on how the apparatus is used).

The inner surface of at least one of the arms may be substantially planar. Both inner surfaces may be substantially planar. The inner surfaces may be substantially parallel. The leading portion may be a leading edge of one of the inner surfaces. The trailing portion may be a trailing edge of one of the inner surfaces.

The outer surface of at least one of the arms may be curved between the leading and trailing openings. The curved outer surface may be concave (and may be arcuate). In some embodiment both outer surfaces may be curved (e.g. concave). When both outer surfaces are concave, together they may form a circular cross-sectional shape (i.e. a transverse cross- sectional shape of the apparatus may be circular). In this respect, and when at least one of the inner surfaces is planar as discussed above, at least one of the arms may have a cross- sectional shape that is semi-circular.

The apparatus may comprise an extraction outlet arranged to extract the fluid discharged by the internal fluid outlet from the hair-receiving space. The extraction outlet may open to the hair receiving space. Thus, the extraction outlet may be disposed on one of the inner surfaces (defining the hair-receiving space).

The extraction outlet may be arranged on a different arm to the internal fluid outlet (e.g. the extraction outlet may be provided on the first arm and the internal fluid outlet may be provided on the second arm). The extraction outlet and internal fluid outlet may be arranged on different inner surfaces. Thus, the extraction outlet and internal fluid outlet may oppose (e.g. directly oppose) one another across the hair-receiving space. In such arrangements, fluid may by discharged from the internal fluid outlet, pass across a tress of hair in the hair-receiving space and then pass into the extraction outlet.

The extraction outlet may be provided on the same arm as the external fluid outlet. Thus, for example, the extraction outlet may be arranged on an inner surface of the first arm (or the second arm) and the external fluid outlet may be arranged on the outer surface of the first arm (or the second arm).

The extraction outlet may be in fluid communication with the external fluid outlet via an extraction passage. That is, an extraction passage may extend from the extraction outlet to the external fluid outlet (for fluid flow from the extraction outlet to the external fluid outlet). The extraction passage may extend through the first or second arm.

In this way, both the internal and external outlet may make use of the same fluid flow (routed via the extraction outlet and the extraction passage). This may result in a more efficient, less complex apparatus (e.g. that requires fewer components).

The apparatus may comprise a fluid inlet in fluid communication with the internal and external fluid outlets. The fluid inlet may be disposed at a portion of the arms at which they are connected (e.g. at the proximal ends of the arms).

The apparatus may comprise a flow director moveable between first and second positions. The flow director may comprise e.g. a vane, valve, obstruction, etc. In the first position the flow director may direct fluid from the inlet to the internal fluid outlet (e.g. substantially all fluid flow received through the inlet may be directed to the internal fluid outlet). In the second position the flow director may direct fluid from the inlet to the external fluid outlet (e.g. substantially all fluid flow received through the inlet may be directed to the internal fluid outlet).

The apparatus may comprise an actuator for moving the flow director between the first and second positions. The apparatus may comprise a user interface (e.g. including a user input device) operatively connected (e.g. mechanically and/or electrically connected) to the actuator. The user input device may comprise, e.g. a button, switch, microphone, touchscreen, accelerometer (for gesture detection), etc.

The actuator may be configured to move the flow director (e.g. between the first and second positions) in response to user interaction with the user interface. In this way, the apparatus may be configured such that a user is able to select a position of the flow director (i.e. so as to select whether fluid is directed to the internal or external outlet).

The external fluid outlet may be configured (e.g. shaped, oriented, positioned) so as to provide a particular function. For example, the external fluid outlet may comprise a diffuser configured to provide a diffused fluid flow. Such a diffused fluid flow may, for example, be particularly suited for curling a tress of hair wrapped about the arms (e.g. extending across the external fluid outlet). The diffuser may comprise an array of perforations (the perforations may be arranged in an ordered pattern to form the array). For example, the diffuser may comprise more than 20, 50, 100, or 200 perforations. Each perforation may, for example, have a diameter (or a width) that is less than 5 mm, or less than 3 mm, or less than 2 mm. In some embodiments, the diffuser may be in the form of a mesh.

In such embodiments (in which the external fluid outlet comprises a diffuser), each arm may comprise an external fluid outlet (being the same as described above). Thus each arm may comprise a diffuser. In this way, a diffused fluid flow may be discharged onto substantially all of a tress of hair that is wrapped about the arms.

In some embodiments, the external fluid outlet may be configured to direct an airflow circumferentially about at least a portion of the apparatus. When at least one of the outer surfaces is curved, the external fluid outlet may be arranged to discharge fluid along the curve of the outer surface. The external fluid outlet may be arranged such that fluid discharged therefrom remains attached (i.e. follows) the curved outer surface. In other words, the external fluid outlet may be arranged so as to exploit the Coanda effect to provide a fluid flow that follows the curved outer surface. In this respect, the curved outer surface may be referred to as a Coanda surface (and the corresponding curved fluid flow may be referred to as a Coanda fluid flow).

Accordingly, the external fluid outlet may be positioned adjacent (or substantially adjacent) to the curved outer surface. In some embodiments, the external fluid outlet may be positioned adjacent (or substantially adjacent) to an intermediate surface that extends from the external fluid outlet to the curved surface (i.e. such that fluid flow attaches to the intermediate surface and then remains attached as it passes across the curved surface). The external fluid outlet may be arranged to discharge fluid in a direction that is tangential to the curved surface.

Such an arrangement (i.e. one in which fluid is directed across a curved surface to exploit the Coanda effect) may facilitate wrapping of a tress of hair about the arm. That is, the fluid flow (which follows the curve of the outer surface) may draw hair against the curved surface. At the same time, such fluid is directed along a tress that is wrapped, which helps to maximise the distance that the flow is adjacent/in contact with the tress. It has been found that such arrangements may facilitate reduction of fly-aways (already discussed above). In particular, it has been found that longer hairs in a tress of hair are more closely held against the curved surface by the Coanda fluid flow than shorter (fly-away) hairs. One result of this is that the flyaway hairs are moved (i.e. pushed) behind the longer hairs (i.e. away from the outer surface of the tress of hair). This provides the styled tress of hair with a smoother appearance (i.e. with fewer fly-aways extending from the tress of hair).

In such embodiments (i.e. where at least one outer surface is curved) each arm may comprise an external outlet (each being as described above). In these embodiments, the outer surfaces of both arms may be curved. The external outlets may be arranged to direct fluid flow in the same direction about the apparatus (i.e. via the Coanda effect) as one another. Thus, for example, both of the external outlets may be arranged to direct fluid in a clockwise direction or in an anti-clockwise direction about the apparatus. Accordingly, a first of the external outlets may be arranged to discharge fluid so as to flow from a first edge of the curved surface of the first arm to an opposite second edge of the curved surface, and a second of the external outlets may be arranged to discharge fluid so as to flow from a second edge of the curved surface of the second arm (adjacent the second edge of the curved surface of the first arm) to a first edge of the curved surface of the second arm. Such an arrangement may facilitate wrapping of a tress of hair about the apparatus as discussed above.

In some embodiments, the external fluid outlet may be arranged to discharge fluid in a direction away from the hair-receiving space. The external fluid outlet may be arranged to discharge fluid in a direction that is substantially parallel to an axis extending between the leading and trailing openings of the hair-receiving space. In such embodiments, when a tress of hair is received in the hair-receiving space, the external fluid outlet may be configured so as to discharge fluid along the tress of hair in use, either in the trailing direction (e.g. towards the scalp of a user) or in the leading direction (e.g. towards the free end of the tress of hair).

Such an arrangement may improve the drying performance of the apparatus because the tress of hair may be dried by both the fluid discharged by the external fluid outlet (along the tress) and the fluid discharged by the internal fluid outlet (onto hair in the hair-receiving space).

Once again, in such arrangements, the apparatus may comprise more than one external fluid outlet (e.g. one on each arm). For example, one external fluid outlet may discharge fluid in the trailing direction and the other may discharge fluid in the leading direction. Alternatively, both external fluid outlets (e.g. one on each arm so as to be either side of a tress of hair) may discharge fluid in the trailing direction or both external fluid outlets (e.g. one on each arm so as to be either side of a tress of hair) may discharge fluid in the leading direction.

In some embodiments the external fluid outlet may be arranged to discharge fluid in a direction that is transverse to an axis extending between the leading and trailing openings of the hairreceiving space. Thus, the external fluid outlet may be arranged to discharge fluid across the leading or trailing opening of the hair-receiving space. Accordingly, in such embodiments, the external fluid outlet may be arranged to discharge fluid onto (e.g. through or across) a leading or trailing portion of a tress of hair (i.e. behind the trailing opening or forward of the leading opening).

Arranging the external fluid outlet to discharge fluid onto a trailing portion of hair may push short hairs of the tress of hair behind longer hairs of the tress of hair so as to reduce the number of short hairs (or fly-aways) that project out from the tress of hair. This may provide the styled hair with a smoother appearance. In such embodiments (i.e. in which an external fluid outlet is arranged to discharge fluid across the leading or trailing opening) the apparatus may comprise a plurality of external fluid outlets (each being as described above). For example, each arm may comprise an external fluid outlet. The external fluid outlets may be arranged to discharge fluid in opposite directions (e.g. towards one another). The external fluid outlets may be disposed on opposed sides of the trailing or leading opening.

As may be appreciated in any of the embodiments described above the external fluid outlet may be arranged at or proximate to the leading opening. Alternatively, the external fluid outlet may be arranged at or proximate to the trailing opening.

The external fluid outlet may comprise a slot and/or a row of apertures extending along an elongate axis of the respective arm. In this way, the external fluid outlet may be configured such that fluid is discharged from the external fluid outlet in the form of a blade or a row of spaced jets.

As has already been discussed, each arm may comprise an external fluid outlet. Likewise, each arm may comprise an internal fluid outlet (the internal fluid outlets may oppose one another across the hair-receiving space). Each arm may comprise an extraction outlet and may further comprise an extraction passage (extending from a respective extraction outlet to a respective external fluid outlet).

The apparatus may comprise a fluid mover configured to move fluid from the inlet to the internal and external outlets. In some embodiments, the fluid may be air and the fluid mover may be an air mover (e.g. pump or fan). In other embodiments the fluid may be steam and the fluid mover may be a steam generator.

Accordingly, the apparatus may comprise an airflow outlet (which may be the internal or external outlet). Likewise, the apparatus may comprise a steam outlet (which may be the internal or external outlet). The steam outlet may be in fluid communication with a steam generator.

Accordingly, the external fluid outlet may be a steam outlet or an airflow outlet, and likewise, the internal fluid outlet may be a steam outlet or an airflow outlet. References below to an “internal steam outlet” are references to an internal fluid outlet (being as described above) in the form of a steam outlet, and references to an “internal airflow outlet” are references to an internal fluid outlet in the form of an airflow outlet. Likewise references below to an “external steam outlet” are references to an external fluid outlet (being as described above) in the form of a steam outlet, and references to an “external airflow outlet” are references to an external fluid outlet in the form of an airflow outlet.

The apparatus may be configured for generating a heated airflow. For example, the apparatus may comprise one or more airflow heaters. Thus, the airflow outlet may be a heated airflow outlet. In such embodiments, the airflow outlet may be in fluid communication with, and downstream of, an air heater for supplying heated air to the internal airflow outlet. Thus, the airflow discharged from the airflow outlet may be a heated airflow. This may facilitate the removal of moisture from the tress of hair. The air heater may comprise a resistive heating element. The air heater may be configured to heat the airflow to a temperature of between 90°C and 170°, or e.g. between 100°C and 160°,

In some embodiments, the apparatus may comprise both an internal airflow outlet and an internal steam outlet (i.e. may include two internal fluid outlets, one for steam and another for airflow). The internal steam outlet may be spaced from the internal airflow outlet in a direction towards the leading opening or leading portion of the apparatus.

The internal steam outlet may comprise an elongate slot and/or a row of apertures. The elongate slot or row of apertures of the internal steam outlet may extend substantially perpendicularly to the movement axis (extending between the leading/trailing portions as discussed above). In this way, steam may be discharged (e.g. in the form of a blade) from the internal steam outlet across a width of a tress of hair (as the apparatus is moved along the tress of hair).

The internal steam outlet may be configured so as to define an outlet flow axis that is angled towards the leading opening (or leading portion). In other words, the internal steam outlet may be configured to direct steam discharged therefrom in a direction that is angled towards the leading opening (or leading portion). This may be achieved, for example, by the orientation of the internal steam outlet (i.e. the orientation of an opening of the internal steam outlet) and/or one or more guide vanes/walls forming part of the internal steam outlet.

The internal airflow outlet may comprise an elongate slot and/or a row of apertures. The elongate slot or row of apertures may extend substantially perpendicularly to the movement axis.

The internal airflow outlet may be configured so as to define a flow axis that is angled towards the leading opening (or leading portion). In other words, the internal airflow outlet may be configured to direct airflow (e.g. heated airflow) discharged therefrom in a direction that is angled towards the leading opening. This may be achieved, for example, by the orientation of the internal airflow outlet and/or one or more guide vanes/walls forming part of the internal airflow outlet.

Accordingly, the internal airflow outlet may be configured to direct air in a direction that forms an angle with the respective inner surface (on which it may be provided) of between 1 degree and 90 degrees, or e.g. between 20 degrees and 90 degrees, or between 35 degrees and 90 degrees. The extraction outlet may be spaced from the internal airflow outlet in a direction towards the leading portion (e.g. along the movement axis). Such an arrangement may be particularly suited to an embodiment in which the internal airflow outlet is configured to direct airflow towards the leading opening.

The extraction outlet may be spaced from the internal steam outlet in a direction towards the trailing opening (or trailing portion). Thus, the extraction outlet may be interposed between (e.g. along the movement axis) the internal airflow outlet and the internal steam outlet. In this way, air may be extracted before it is able to mix with steam that is discharged from the internal steam outlet. This may ensure the temperature of the steam is not reduced by the airflow discharged from the internal airflow outlet, which could otherwise be detrimental to the performance of the apparatus.

The extraction outlet may be configured such that a flow axis of the extraction outlet is angled towards the trailing opening. This may be achieved, for example, by the orientation of the extraction outlet and/or one or more guide vanes/walls forming part of the extraction outlet.

The apparatus may comprise a gripping portion for gripping the tress of hair. For example, the gripping portion may be provided on one of the inner surfaces. This may allow tension to be applied to a tress of hair as the apparatus is moved along it in use.

The gripping portion may be closer to the leading opening (or leading portion) than both the internal steam outlet and internal airflow outlet. The gripping portion may be disposed at (or proximate to) the leading opening (or leading portion). In this way, in use, a portion of the hair extending across the internal steam outlet and the internal airflow outlet in use may be under tension. The gripping portion may be elongate and may extend substantially perpendicularly to the movement axis. The gripping portion may comprise a flexible plate (e.g. a tensioning plate). The gripping portion may be formed of a resilient material (e.g. may be a resilient member).

The apparatus may comprise an intermediate sealing portion projecting from one of inner surfaces. The intermediate sealing portion may be interposed between the internal steam outlet and the internal airflow outlet along the movement axis and may be configured to seal the discharged air from the discharged steam in use. The intermediate sealing portion may be elongate and may be parallel to a longitudinal axis of the arm on which it is provided. The intermediate sealing portion may be formed of a resilient material.

The apparatus may comprise a trailing sealing portion projecting from one of the inner surfaces. The trailing sealing portion may be spaced from the internal airflow outlet in a direction of the trailing opening (or trailing portion). The trailing sealing portion may be elongate and may be parallel to a longitudinal axis of the arm on which it is provided. The trailing sealing portion may be formed of a resilient material. The apparatus may further comprise end sealing portions disposed at distal and/or proximal ends of one or both of the inner surfaces. The end sealing portions may prevent air from escape from the ends of the hair-facing surfaces. In this way, air and steam may be substantially contained between the arms.

In some embodiments, the internal airflow outlet described above may be a first internal airflow outlet and the apparatus may comprise a second internal airflow outlet. The second internal airflow outlet may be spaced from the first internal airflow outlet along the movement axis. The second internal airflow outlet may be spaced from the first internal airflow outlet in a direction towards the trailing opening or trailing portion (i.e. may be closer to the trailing opening than the first internal airflow outlet). The steam outlet may be interposed between the first and second internal airflow outlets. In this way, when the apparatus is moved along a tress of hair along the movement axis, heated air will be applied to a portion of the tress both before and after the application of steam, regardless of the direction of movement along the axis. Thus, a drying airflow will be provided after steam application regardless of the direction of movement along the movement axis. In other words, such embodiments may be configured for bidirectional movement. As may be appreciated, and as has already been discussed above, when the direction of movement is reversed, the leading portion and trailing portion may be interchangeable (i.e. each portion acts as both a leading portion and a trailing portion).

In some embodiments the first and second internal airflow outlets may form different portions of a single internal airflow outlet (e.g. the single airflow outlet may be U-shaped, the legs of the “U” providing the first and second internal airflow outlets).

In some embodiments the steam outlet (whether an internal or external steam outlet) and steam generator form part of a steam supply system of the apparatus. The steam generator may comprise a cavity for receipt of water to generate steam. The steam outlet may be in fluid communication with the cavity. The steam generator may be elongate, so as to have an elongate axis.

The steam generator may comprise a heating element for heating water in the cavity. The heating element may be a resistive heating element (i.e. may generate heat from electrical resistance). The steam generator may substantially enclose the heating element. For example, the heating element may be at least partly embedded within the steam generator.

The heating element may be a first heating element of the steam generator and the apparatus may comprise a second steam generator heating element. The first and second steam generator heating elements may be spaced either side of the cavity.

The cavity of the steam generator may comprise a passage (e.g. may be in the form of a passage). The passage may extend through the steam generator from an inlet to an outlet of the steam generator. The passage may comprise at least one bend (e.g. a 180 degree bend). The outlet of the steam generator may be in the form of an elongate slot or a plurality of apertures spaced along a linear path. The elongate slot or plurality of apertures may be parallel to the elongate axis of the steam generator.

The airflow outlet(s) and air mover may form part of an air supply system. The apparatus may comprise an airflow path that extends from the fluid inlet (e.g. an airflow inlet) to the airflow outlet(s) (i.e. the first and/or second airflow outlet when present). A portion of the airflow path may be in thermal communication with the steam supply system for transfer of heat from the steam supply system to air in the airflow path. In such embodiments the apparatus may not require the air heater described above (i.e. the heat from the steam supply system may replace the need for the air heater).

The air mover may be arranged to move air along the airflow path. The air mover may be in the form of a pump or a fan. The flow rate provided by the air mover may be controllable. Thus, the air mover may be controllable to control the flow rate of air along the airflow path and thus the flow rate of air from the airflow outlet(s). The air mover may be configured to provide a flow rate of between 2L/s and 20 L/s, or e.g. between 3L/s and 15 L/s, or e.g. between 5L/s and 14 L/s. For the avoidance of doubt, flow rates referred to herein are references to volumetric flow rate.

The air mover may be upstream of the steam generator. In this way, the air mover may interact with unheated airflow (which may be desirable to minimise degradation of the air mover).

The apparatus may comprise a water reservoir and a water flow path extending from the reservoir to the steam generator (e.g. the cavity of the steam generator). The reservoir may be removable from the apparatus to allow it to be filled with water. The reservoir may comprise an opening for filling the reservoir with water.

The apparatus may comprise a water pump configured to move water from the reservoir to the steam generator. The pump may be configured to control the flow rate of water from the reservoir to the steam generator. The flow rate provided by the pump may be controllable. Thus, the pump may be controllable to control the flow rate of water from the reservoir to the steam generator. Control of the flow rate of pump may control generation of steam in the steam generator and thus the flow rate of steam from the steam outlet.

The apparatus may be configured to discharge steam at a flow rate of between 1 ml/min and 20 ml/min, or e.g. between 2 ml/min and 15 ml/min, or e.g. between 2.5 ml/min and 10 ml/min (e.g. the water pump may be configured to provide steam generation for the provision of such flow rates).

The pump may be downstream of the reservoir. The pump may be mounted at an outlet of the reservoir. The pump may be upstream of the steam generator. The apparatus (e.g. the steam supply system) may comprise a steam flow path downstream of the steam generator (extending from the steam generator to the steam outlet). The apparatus may be configured such that the steam flow path remains open during operation of the apparatus. The apparatus may be configured such that the steam flow path is free of valves or other obstructions (capable of fully obstructing the steam flow path). Such an arrangement may provide the apparatus with improved safety because it can eliminate (or at least reduce) the possibility of a dangerous build-up of pressure in the steam generator or steam flow path. Such a build-up of pressure could otherwise occur if there was inadvertent blockage of the steam flow path in operation (such as a blockage caused by a faulty valve or pump).

The apparatus may comprise a heat exchanger providing the thermal communication between the steam supply system and the airflow path (the heat exchanger may be configured to transfer heat from the steam supply system to the airflow path). In this way, the heat exchanger may define an air heater of the apparatus.

The heat exchanger may be elongate, so as to extend along an elongate axis thereof.

The heat exchanger may be configured to heat the airflow to a temperature of between 90°C and 170°, or e.g. between 100°C and 160°,

The heat exchanger may comprise a thermally conductive material. For example, the heat exchanger may comprise a metal (e.g. copper or aluminium) or a ceramic.

The heat exchanger may be, or may form part of (e.g. a body of), the steam generator. Thus, the heat exchanger may comprise a first portion in contact with the steam generator heating element. The first portion may be mounted to or integral with the heating element. The heat exchanger may comprise a second portion defining a heat exchange surface across which the airflow path passes.

In other embodiments, the heat exchanger may provide heat exchange between the airflow path and a part of the steam supply system other than the heating element. For example, the heat exchanger may be configured to exchange heat between the steam flow path (downstream of the steam generator) and the airflow path. Thus, the first portion of the heat exchanger may be in contact with the steam flow path (instead of the heating element as described above).

In some embodiments, the heating element of the steam generator may be external to the cavity of the steam generator. In such embodiments, and when the heat exchanger is, or forms part of, the steam generator, the heat exchanger may be configured to transfer heat from the heating element to the cavity. In other embodiments, the heating element may be disposed within the cavity so as to heat water in the cavity directly. In such embodiments, the heat exchanger may be configured to receive heat from water/steam disposed in the cavity (and transfer that heat to the airflow path). The heat exchanger may comprise one or more fins projecting into the airflow path (i.e. defining the heat exchange surface of the heat exchanger). The one or more fins may be configured to redirect airflow along the airflow path (i.e. may be configured to turn the airflow as it passes across the heat exchanger).

In this respect, the one or more fins may extend at an angle to (e.g. may be substantially perpendicular to) the direction of the airflow path at an upstream end of the heat exchanger. The one or more fins may extend at an angle to (e.g. may be generally perpendicular to) the elongate axis of the heat exchanger. Accordingly, in an embodiment where the airflow path (at least initially) passes along the heat exchanger in a direction of its elongate axis, the one or more fins may divert the airflow path away from the elongate axis.

The one or more fins may define an airflow channel on a side of the heat exchanger (e.g. a side of the heat exchanger opposite to the outlet of the heat exchanger). The airflow channel may be configured to distribute airflow to recesses formed between adjacent fins. The airflow channel may be parallel to a direction of the airflow path at the upstream end of the heat exchanger. The airflow channel may be parallel to the elongate axis of the heat exchanger.

The airflow channel may taper inwardly (e.g. in a direction of airflow along the channel in use).

One of the first and second elongate arms may house the steam generator and/or heat exchanger. An airflow plenum may be defined in one or both arms. The or each airflow plenum may be defined between an internal surface of the respective arm and an outer surface of the heat exchanger when present. The airflow path may pass through the airflow plenum. The or each airflow plenum may substantially surround the heat exchanger when present.

In such embodiments, the airflow path may split into two branches (e.g. downstream of the air mover), one branch passing through the first arm and the other passing through the second arm. Similarly, when each arm houses a steam generator, the water flow path may split into two branches (e.g. downstream of the pump), one branch extending to the cavity of a steam generator of the first arm and the other branch extending to the cavity of a steam generator of the second arm.

The apparatus may comprise a further internal steam outlet. The further internal steam outlet may be disposed on a different inner surface to the internal steam outlet. The internal steam outlet may oppose (e.g. directly oppose) the further internal steam outlet (e.g. when the apparatus is in the closed position).

The apparatus may comprise a further internal airflow outlet. The internal airflow outlet (i.e. the first internal airflow outlet) may be disposed on the inner surface of the first arm and the further internal airflow outlet may be disposed on the inner surface of the second arm. The internal airflow outlet may oppose (e.g. directly oppose) the further internal airflow outlet (at least when the apparatus is in the closed position). When the apparatus includes first and second internal airflow outlets (as discussed previously), the apparatus may comprise further first and second internal airflow outlets. The first and second internal airflow outlets may be disposed on the inner surface of the first arm and the further first and second internal airflow outlets may be disposed on the inner surface of the second arm. The first and second internal airflow outlets may oppose (e.g. directly oppose) the further first and second internal airflow outlets (e.g. when the apparatus is in the closed position).

Accordingly, each arm of the apparatus may comprise internal airflow outlet(s) and an internal steam outlet. These may directly oppose the internal airflow outlet(s) and internal steam outlet of the other arm. In this way, when the apparatus is in the closed position clamping a tress of hair, steam may be applied to both sides of the tress of hair at the same point along the length of the tress. Likewise, airflow will be applied to both sides of the tress of hair at the same point(s) along the tress of hair.

These embodiments may be suited to arrangements in which an extraction outlet is provided on each arm, interposed between the internal airflow outlet(s) and the internal steam outlet. In other embodiments, however, the or each extraction outlet may be provided on an opposing inner surface to a respective internal airflow outlet. In such embodiments, the or each extraction outlet may oppose the respective internal airflow outlet (e.g. directly oppose) so that the extraction outlet is configured to receive air from the respective internal airflow outlet.

In these embodiments, and when the apparatus includes a second internal airflow outlet (as described further above), the first internal airflow outlet may be on the inner surface of the first arm and the second internal airflow outlet may be on the inner surface of the second arm. The extraction outlet may be a first extraction outlet. The first extraction outlet may be provided on the inner surface of the first arm and may oppose (i.e. substantially directly oppose) the second airflow internal outlet. In this way the first extraction outlet may receive (and extract) air that has passed through a tress of hair from the second internal airflow outlet. Likewise, the apparatus may comprise a second extraction outlet. The second extraction outlet may be arranged on the inner surface of the second arm and may oppose (i.e. substantially directly oppose) the first internal airflow outlet. In this way, the second extraction outlet may receive (and extract) air that has passed through a tress of hair from the first internal airflow outlet.

The first internal airflow outlet and second extraction outlet may be disposed proximate to the leading portions and the second internal airflow outlet and first extraction outlet may be disposed proximate to the trailing portions.

The apparatus may comprise a controller. The controller may comprise a processor, e.g. a microprocessor. The controller may be configured to control the volumetric flow rate of steam discharged from the apparatus and the volumetric flow rate of air discharged from the apparatus. For example, the controller may be configured to control the water pump and/or the air mover. The controller may be configured to control the heating element(s).

The controller may be configured to control the apparatus to operate according to a steam phase in which steam is discharged from the steam outlet and air is not discharged from the airflow outlet(s).

The controller may be configured to control the apparatus to operate according to a drying phase in which air is discharged from the airflow outlet(s) and steam is not discharged from the steam outlet.

The controller may be configured to switch between the steam phase and the drying phase in response to a user input received by the user input device.

The controller may be configured to control the volumetric flow rate of steam discharged from the apparatus and the volumetric flow rate of air discharged from the apparatus in response to a user input received by the user input device.

The controller may be configured to control activation of the steam generator/heating element in response to a user input received by the input device.

The apparatus may be a handheld device. For example, the apparatus may be handheld hair straightening device. Alternatively, the apparatus may, for example, be a heated brush.

Brief Summary of the Figures

Embodiments will now be discussed with reference to the accompanying figures in which:

Figure 1 A is a perspective view of a first embodiment of a hair styling apparatus;

Figure 1 B is a section view of the first embodiment of the hair styling apparatus;

Figure 1C is a detailed view of a hair-facing surface of the first embodiment of the hair styling apparatus;

Figure 2 is a detailed view of a second embodiment that includes a variation of the hair-facing surface of the first embodiment;

Figures 3A, 3B and 3C are top, side and end views respectively of a heat exchanger for use in the second embodiment of the hair styling apparatus;

Figure 4 is a schematic section view of a third embodiment of a hair styling apparatus;

Figure 5 is a schematic section view of a fourth embodiment of a hair styling apparatus; and

Figures 6 to 8 are perspective views illustrating various external outlet configurations. Detailed Description

Aspects and embodiments will now be discussed with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art.

Figures 1A and 1B illustrate a hair styling apparatus 100 in the form of a hair straightening device. The apparatus 100 comprises two arms 101 that each have a proximal end 102 at which they are hingedly connected and an opposite distal end 103 (which is a free end of each arm). Each arm 101 comprises an elongate housing 104 (extending along a longitudinal axis) that includes an in-use hair-facing surface 105. The hair-facing surfaces 105 are both generally planar and define inner surfaces of the arms 101 so as to face inwardly towards one another. Each hair-facing surface 105 extends between a longitudinally extending leading portion in the form of a leading edge 106 (lower edge as illustrated) and a longitudinally extending trailing portion in the form of a trailing edge 107 (upper edge as illustrated). In normal use, the apparatus 100 can be moved along a tress of hair such that the leading edges 106 lead in movement along the tress of hair and the trailing edges 107 trail in movement along the tress of hair.

The figures depict the apparatus 100 in an open position in which the arms 101 are hinged open and away from one another and the hair-facing surfaces 105 are both spaced and angled with respect to one another. In this position an acute angle is formed between the hair-facing surfaces 105 and, likewise, between the longitudinal axes of the arms 101. In this way, a hairreceiving space (or cavity) is defined between the arms 101 (i.e. between the hair-facing surfaces 105 of the arms) for receipt of a tress of hair to be styled. This hair-receiving space has opposed trailing 147 and leading 148 openings through which a tress of hair extends in use.

The arms 101 can be moved from the depicted open position to a closed position. This is performed by pivoting movement of the arms 101 about their hinged connection at their proximal ends 102. In the closed position (which is not depicted) the hair-facing surfaces 105 of the arms 101 are brought together (so as to either be in contact or at least proximate to one another). In this position the longitudinal axes of the arms 101 are substantially parallel and are likewise parallel with the longitudinal (i.e. elongate) axis of the apparatus 100 taken as a whole.

In use, a tress of hair received between the hair-facing surfaces 105 can be clamped between the arms 101 (and hair-facing surfaces 105) by movement of the apparatus 100 from the open position to the closed position.

Figure 1 B depicts the internal structure of the apparatus 100 schematically. As is apparent from this figure, the apparatus 100 comprises a component housing 108 disposed between the arms 101 and positioned towards their distal ends 103. Together, the component housing 108 and the arms 101 house several components of the apparatus 100 that form part of a steam supply system of the apparatus 100. Also housed within the component housing 108 is an air mover 109, in the form of an air pump, that forms part of an airflow supply system of the apparatus 100. The steam supply system and airflow supply system will now be described in more detail with reference to Figure 1B.

The steam supply system comprises a water reservoir 110 for storing water, two heat exchangers 111 that each define a cavity 112 for receipt of water, heating elements (not shown) for heating water in the cavities 112 to generate steam, and two internal steam outlets 113 for discharging steam that is generated by the heating elements. The steam supply system further includes a pump 114 configured to move water from the water reservoir 110 to the heat exchanger cavities 112 along a water flow path 115.

The water flow path 115 extends from the water pump 114 around the air mover 109 (as illustrated in Figure 1 B) and then splits into two branches (only one branch is shown), each branch passing along a respective arm 101 to a corresponding heat exchanger 111. Accordingly, when the water pump 114 is active, water is moved by the water pump 114 from the water reservoir 110 to the cavity 112 of each heat exchanger 111 (along the water flow path 115), which is then heated by the heating elements to form steam. In this respect, the heat exchangers 111 form steam generators of the apparatus 100. The steam generated by the heat exchangers 111 flows along respective steam flow paths 117 to the internal steam outlets 113 for discharge from the apparatus 100.

The water reservoir 110, which is at an upstream end of the steam supply system, is positioned towards the proximal ends 102 of the arms 101 and includes an inlet 116, closable by a closure (e.g. cap), for filling thereof. In other embodiments, the entire water reservoir may be removable from the apparatus 100 for filling. The water pump 114 is disposed downstream of the water reservoir 110 at an outlet of the water reservoir 110 so as to be able to draw water from the reservoir 110 and move it towards the heat exchangers 111 along the water flow path 115. In this way, the rate of steam generation provided by the heating elements (and thus the flow rate of steam discharged through the internal steam outlets 113) can be controlled by controlling the flow rate of the pump 114.

By positioning the water pump 114 upstream of the heat exchangers 111, it is possible to maintain each steam flow path 117 in an open (i.e. unobstructed) condition during operation. This can improve safety because it eliminates the possibility of a pressure build up resulting from e.g. a fault in a pump forming a blockage downstream of the point in the system at which steam is generated.

As provided above, the two steam flows paths 117 each extend from a respective heat exchanger 111 to a respective steam outlet 113 formed in the respective arm. In the illustrated embodiment those steam flow paths 117 are very short, because the heat exchangers 111 are located adjacent to the internal steam outlets 113 formed in the arms 101. However, in other embodiments, for example where one or more heat exchangers are instead provided in the component housing 108, the steam flow paths may be longer (e.g. they may extend along one or both arms).

Turning now to the air supply system, the apparatus 100 is provided with airflow inlets 118 formed at the proximal end 102 of each arm 101 and which define an upstream end of an airflow path 119 of the air supply system. The airflow inlets 118 each comprise a plurality of apertures that are formed in a grid-like pattern and that extend circumferentially about the proximal ends of the arms 101.

The airflow path 119 extends from the airflow inlets 118 and through the air mover 109. From the air mover 109 the airflow path 119 extends to internal airflow outlets 120, provided in each hair-facing surface 105 (external airflow outlets 145 are also provided, but these are described in more detail further below). As is apparent from the figure, a portion of the airflow path 119 passes across a surface (referred to herein as a heat exchange surface) of each heat exchanger 111. Each heat exchanger 111 is configured to transfer heat from the steam supply system (specifically each cavity 112 and heating element of the steam supply system) to this portion of the airflow path 119 via the heat exchange surface. To facilitate this heat exchange, the heat exchanger 111 comprises a plurality of fins 121 across which the airflow path 119 passes.

In this way, the air is heated by the heat exchanger 111 and a separate dedicated air heater is not required. This reduces the complexity of the apparatus 100, which in turn can improve one or more of cost, reliability, and size of the apparatus.

The airflow path 119 downstream of the air mover splits into two branches (only one branch is shown), each passing along a respective internal airflow plenum 122 formed in a respective arm 101 of the apparatus 100. Thus, air heated by the heat exchanger 111 passes through the arms 101 and is discharged through the internal airflow outlets 120.

Each internal airflow outlet 120 is in the form of a slot that extends longitudinally along the respective hair-facing surface 105 in which it is formed. This is particularly apparent from Figure 1C, which provides a detailed view of the hair-facing surface 105 of one of the arms 101. It should be appreciated that the hair-facing surface 105 of the other arm 101 is the same, except for having a reversed orientation (such that the airflow outlets 120 and steam outlets 113 of the two arms 101 directly oppose one another).

As is apparent from this figure, each steam outlet 113 (like each internal airflow outlet 120) is in the form of an elongate slot that extends along a respective hair-facing surface 105 of the arm 101 in a longitudinal direction of the arm 101 (or the arm housing 104). The elongate nature of the internal steam 113 and airflow 120 outlets means that steam and airflow can be applied across the width of a tress of hair in use. The internal steam outlet 113 is parallel to the internal airflow outlet 120 and transversely spaced therefrom along the hair-facing surface 105. In particular, the internal steam outlet 113 is spaced from the internal airflow outlet 120 in a direction towards the leading edge 106 along a movement axis (depicted with dashed/dotted line) of the apparatus 100 which extends from the trailing edges 107 to the leading edges 106 of the hair-facing surfaces 105. The movement axis represents an axis along which the apparatus 100 is moved along a tress of hair in normal use and is perpendicular to the longitudinal axes of the arms 101.

This arrangement of the internal steam outlets 113 and the internal airflow outlets 120 means that, in normal use when the apparatus 100 is in the closed position and moved along a tress of hair, steam is firstly applied to a portion of the tress of hair and, subsequently, heated air is applied to the same portion of the tress of hair. In this way, the heated air can remove moisture from the portion of the tress of hair that is present from the application of the steam.

To assist this process, each arm 101 of the apparatus 100 also includes a gripping portion 123 configured to grip a tress of hair received between the hair-facing surfaces 105. This allows tension to be applied to a tress of hair as the apparatus 100 is moved along the tress in use. In other words, the gripping portions 123 grip the tress of hair therebetween so as to pull it straight as the apparatus 100 is moved along the tress. The gripping portions 123 are each in the form of a flexible tensioning plate extending along the hair-facing surface 105 in the longitudinal direction (i.e. being elongate in the longitudinal direction). Each gripping portion 123 extends for substantially the entire length of the respective hair-facing surface 105 on which it is provided and is spaced from the corresponding steam outlet 113 (along the movement axis) in a direction towards the leading edge 106 of the hair-facing surface 105 (so as to be proximate the leading edge 106). This positioning of each gripping portion 123 means that hair extending across both the steam outlets 113 and the internal airflow outlets 120 of each arm 101 is placed under tension. This can aid in shaping the hair.

Each arm 101 also includes an intermediate sealing portion 124 and a trailing sealing portion 125 that both project from, and extend longitudinally along, the hair-facing surface 105 of the arm 101. The intermediate sealing portion 124 of each arm 101 is interposed between the steam outlet 113 and the internal airflow outlet 120 of that arm 101. When the hair-facing surfaces 105 of the arms 101 are brought together (i.e. in the closed position), the intermediate sealing portions 124 seal air discharged from the internal airflow outlets 120 from steam discharged from the internal steam outlets 113. This prevents (or at least reduces) mixing of the air with the steam which could otherwise cool and/or disperse the steam so as to reduce its effectiveness.

The trailing sealing portion 125 of each arm 101 is spaced from the internal airflow outlet 120 (along the movement axis) in a direction of the trailing edge 107, so as to be disposed proximate the trailing edge 107. When the arms 101 are in the closed position, the trailing sealing portions 125 seal discharged air from air that is external to the apparatus 100.

To control the application of steam and heated air to a user’s hair, the apparatus 100 comprises a controller 126 (see Figure 1 B). The controller is configured to control the water pump 114, air mover 109, and the heating elements (not shown). In particular, the controller 126 of this embodiment is configured to control the apparatus 100 according to five different configurations. A user is able to select a particular configuration using a user input device of the apparatus, which comprises push buttons 127.

In a first configuration, the air mover 109 is controlled to provide a flow rate of approximately 5 L/s, the water pump 114 is controlled to provide a flow rate of 2.5 ml/min and the heating element 112 is controlled to provide an air temperature of 110°C.

In a second configuration, the air mover 109 is controlled to provide a flow rate of approximately 8 L/s, the water pump 114 is controlled to provide a flow rate of 7 ml/min and the heating element 112 is controlled to provide an air temperature of 130°C.

In a third configuration, the air mover 109 is controlled to provide a flow rate of approximately 13.5 L/s, the water pump 114 is controlled to provide a flow rate of 10 ml/min and the heating 112 element is controlled to provide an air temperature of 150°C.

In a fourth configuration, the air mover 109 is deactivated (so that no airflow is discharged from the internal airflow outlets 120), the water pump 114 is controlled to provide a flow rate of 10 ml/min, and the heating element is activated (with a power input of 260W). In this configuration, only steam is discharged from the apparatus 100.

In a fifth configuration, the air mover 109 is controlled to provide a flow rate of 5 L/s, the water pump 114 is deactivated, and the heater is activated (with a power input of 260w). In this configuration, only heated air (at about 130°C) is provided.

In a sixth configuration the air mover 109 is controlled to provide a flow rate of 8 L/s, and the water pump 114 and heating element 112 are deactivated. In this configuration only ambient air is discharged from the apparatus 100.

The first, second and third configurations allow a user to steam and dry a tress of hair concurrently as it is moved along a tress of hair (due to the apparatus 100 discharging both steam and air in these configurations). These configurations may each be suited to a particular hair type (e.g. wavy, curly or kinked hair).

A user may use the fourth, fifth and sixth configurations in a series of multiple passes (i.e. changing the configuration between passes) to achieve a similar effect.

The above description of the apparatus 100 is focused on the use of the apparatus 100 by movement of the apparatus 100 along a tress of hair. As will now be described, the apparatus 100 is also configured to style a tress of hair by wrapping the tress of hair about the arms 101 of the apparatus 100. To provide this, as mentioned above, each arm 101 comprises an external airflow outlet 145 (as shown in Figure 1A) that comprises a diffuser formed of an array of perforations. Accordingly, each external airflow outlet 145 is configured to discharge airflow in a diffused manner (i.e. at low velocity and distributed over a significant area). Each external airflow outlet 145 wraps about an external portion of a respective arm housing 104 such that when the arms 101 are brought together (i.e. in the closed position), the external outlets 145 (together) form a substantially cylindrical shape. This ensures that when a tress of hair is wrapped about the arms 101, substantially all of the wrapped portion of the tress will be adjacent to an external outlet 145 (such that air will be discharged onto the tress).

In this way, the apparatus 100 may be used, for example, to curl a user’s hair (by application of heated air thereto). The diffused nature of the discharged air may decrease turbulence in the styled hair.

Although not apparent from the figures, the external outlets 145 are fluidly connected to the airflow path 119 (and to the heat exchangers 111). The apparatus 100 comprises flow directors (not shown) that are capable of selectively directing airflow from the inlets 118 to one of the internal airflow outlets 120 and the external airflow outlets 145 (by restricting flow to one of the internal airflow outlets 120 and external airflow outlets 145). The flow directors are controllable by the push buttons 127 such that a user can select whether heated air is discharged from the external airflow outlets 145 or the internal airflow outlets 120.

It should be appreciated that variations of embodiment described above and illustrated in Figures 1A, 1 B and 1C may be provided. For example, Figure 2 illustrates one arm 10T of an apparatus according to embodiment that is a variation of the apparatus 100 described above in which the hair-facing surface 105 is provided with a different arrangement of outlets. It should be appreciated that this embodiment may otherwise be the same as the embodiment described above. Hence, this variation includes many of the same features as the previously described embodiment and accordingly, the same reference numerals have been used for such features.

In this variation, two internal airflow outlets 120 are provided. The internal airflow outlets 120 both extend longitudinally and are spaced (transversely) either side of the steam outlet 113. In this way, when the apparatus is moved along a tress of hair along the movement axis (perpendicular to the longitudinal axis), heated air will be applied to a portion of the tress both before and after the application of steam, regardless of the direction of movement along the axis. Thus, a drying airflow will be provided after steam application regardless of the direction of movement along the axis. In other words, the apparatus of this embodiment is configured for bidirectional movement.

To further support this bidirectional movement, each arm 10T of the apparatus comprises two gripping portions 123 (each being the same as that described with respect to Figure 1C). The gripping portions 123 extend longitudinal along longitudinally extending edges of the hair facing surface 105 of each arm 10T. In this way, regardless of the direction of movement, the hair extending across the internal airflow outlets 120 and steam outlet 113 will be placed under tension.

To prevent mixing of discharged airflow and steam, each arm 10T includes two longitudinally extending intermediate sealing portions 124 (projecting from the hair-facing surface 105). Each of these is interposed between a steam outlet 113 and an internal airflow outlet 120.

Figures 3A, 3B and 3C provide detailed views of a heat exchanger 11 T that is suited for use with the bidirectional variation of Figure 2. It should be appreciated, however, that this heat exchanger 11 T could also be used with the apparatus 100 of Figures 1A-1C with structural modification to provide a single airflow at the airflow outlet 113.

The heat exchanger 11 T comprises a cavity 112 for receipt of water from a water reservoir (not shown). The cavity 112 is in the form of a central longitudinally extending passage formed of first 128 and second 129 parallel passage portions. The first passage portion 128 extends from an inlet of the cavity 112 at a proximal end 130 of the heat exchanger 11 T to a distal end 131 of the heat exchanger 11 T. The second passage portion 129 extends from (and is connected to) the first passage portion 128 at the distal end 131 and extends in the opposite direction back towards the proximal end 130 of the heat exchanger 11 T. The second passage portion 129 extends along a hair-facing side 132 of the heat exchanger 111’, while the first passage portion

128 extends along an opposite rear side 133 of the heat exchanger 11 T. The outlet 134 of the heat exchanger 11 T is in the form of an elongate slot that extends along the hair-facing side 132, so as to define an opening to the second passage portion 129. Hence, water flows into the cavity 112, is heated to form steam, and is then discharged from the second passage portion

129 via the heat exchanger outlet 134.

To heat water in the cavity 112, the apparatus 100 comprises two resistive heating elements 135 that are embedded in the heat exchanger 11 T. The heating elements 135 are spaced either side of the cavity 112 and extend longitudinally alongside the cavity 112. Power is supplied to the heating elements 135 via a power source (not shown), which may be in the form of a battery or an external power source (i.e. via wired connection from the apparatus 100).

The fins 121 of the heat exchanger 11 T extend in a transverse direction (perpendicular to the elongate axis of the heat exchanger 11 T and to the initial direction of airflow across it). The fins 121 extend across three sides of the heat exchanger 11 T: the rear side 133, an upper side 136 and a lower side 137. A tapered channel 138 (that tapers inwardly in the direction of initial airflow) is defined by the fins 121 on the rear side 133 of the heat exchanger 11 T. This aids in distribution and redirection of the airflow that passes across the heat exchanger 11 T. In operation, air passes along this channel 138 in a longitudinal direction and is then redirected transversely around the sides of the heat exchanger 11 T by the fins 121 before being discharged via the internal airflow outlets 120 of the apparatus.

In addition to providing this guiding function, the fins 121 increase the surface area of the heat exchanger 111’ that is exposed to the airflow. This facilitates transfer of heat from the heat exchanger 11 T (which in turn is received from the heating elements 135 and cavity 112) to airflow in the airflow plenum 122.

Figure 4 illustrates an apparatus 100” according to a third embodiment that represents a further modification of the apparatus 100 of figures 1A, 1B and 1C. Again, given this embodiment includes many of the same features as the previously described embodiments, the same reference numerals are used to refer to similar features.

In this embodiment, each arm 101 of the apparatus 100” further comprises an extraction portion 139 for extraction of air that has been discharged by the internal airflow outlets 120 (i.e. after that air has passed across the tress of hair). Each extraction portion 139 comprises an extraction outlet 140 and an extraction passage 141 that passes from the hair-facing surface 105 of the respective arm 101 to an opposing rear surface 142 of the arm, where the extracted air is discharged from the apparatus 100” via an external airflow outlet 145. As may be appreciated, the air may be discharged from the external airflow outlets 145 in the same manner as described with respect to Figure 1A (i.e. in a diffused manner). Alternatively, the air may be discharged from the external airflow outlets 145 in accordance with one of the configurations illustrated in Figures 6 to 9 (which are described further below).

To facilitate the extraction of the air, the internal airflow outlets 120 are oriented so as to direct airflow in a direction towards the leading edges 106 of the hair-facing surfaces 105. That is, an angle formed between a flow axis extending centrally through each internal airflow outlet 120 forms an acute angle with the movement axis in a direction towards the leading edge 106. The extraction openings 140 are oriented in an opposing manner, so as to be configured to receive the airflows discharged from the internal airflow outlets 120.

Like the internal airflow outlets 120, the steam outlets 113 are oriented so as to direct airflow in a direction towards the trailing edges 107. This directs steam away from the airflow and helps to ensure that the steam and airflow do not mix.

In addition to the extraction portion 139, this embodiment differs from those previously described in that each arm 101 is provided with a steam plenum 143 and an airflow plenum 144 that are separated by the extraction passage 141. The steam and air may be provided to these plenums 143, 144 via a single heat exchanger (e.g. disposed upstream of the plenums, such as in a component housing), or the steam may be provided by a steam generator and the heated air may be provided by an air heater. Figure 5 illustrates a hair styling apparatus 100”’ according to a further embodiment. In this embodiment, each hair-facing surface 105 includes a single internal steam outlet 113, a single internal airflow outlet 120a, 120b, and a single extraction outlet (or opening) 140a, 140b. The internal airflow outlet 120a of a first arm 101a of the arms 101a, 101b is disposed proximate to the leading edge 106a of first arm 101a, and the extraction outlet 120a of the first arm 101a is disposed proximate to the trailing edge 107a. On the other hand, the internal airflow outlet 120b of a second arm 101b of the arms 101a, 101b is disposed proximate to the trailing edge 107b of the arm 101b and the extraction outlet 140b is disposed proximate to the leading edge 106b. In particular, each airflow outlet 120a, 120b directly opposes a corresponding extraction outlet 140a, 140b of the other arm 101a, 101b.

In this way, the apparatus 100”’ is configured such that air discharged from the internal airflow outlets 120a, 120b passes through a tress of hair (received between the arms 101a, 101b) and into a corresponding extraction outlet 140a, 140b (for subsequent extraction from the apparatus 100’”). Like the embodiment of Figure 2, the present apparatus 100’” is configured for bidirectional use along a tress of hair, because internal airflow outlets 120a, 120b are provided either side of the internal steam outlets 113. Accordingly, the leading edges 106a, 106b may become trailing edges (i.e. may trail in use) and the trailing edges 107a, 107b may become leading edges (i.e. may lead in use).

Each extraction outlet 140a, 140b is in communication with an extraction passage 141 that extends circumferentially about a periphery of a respective arm 101a, 101b. The rear surface 142 of each arm 101a, 101b includes an external airflow outlet 145 in the form of a plurality of radially directed apertures that from which air in the airflow passages 141 is discharged in a diffused manner (similar to the arrangement of Figure 1A).

Each arm 101a, 101b includes a heat exchanger 111 enclosing heating elements 135 and defining a passage 112 in which steam is formed (by way of heat from the heating elements 135). Each heat exchanger 111 also includes a plurality of outwardly extending fins 121. Air passes along longitudinally extending airflow plenums 144 in each arm 101a, 101b and is then redirected around a respective heat exchanger 111 by the fins 121 (before being discharged through an internal airflow outlet 120a, 120b). Walls 146, which extend in a circumferential direction, divide each airflow plenum 144 from each corresponding extraction passage 141 disposed radially outwardly of the respective airflow plenum 144. In this way, each airflow path follows a spiral shape through the apparatus 100’”.

To allow a user’s tress of hair to be placed under tension while the apparatus 100’” is moved along it, the apparatus 100’” includes four gripping portions 123. Each gripping portion 123 is in the form of an elongate resilient member and is disposed adjacent a respective leading 106a, 106b or trailing 107a, 107b edge of the apparatus 100’”. This means that, in addition to tensioning a user’s hair, the gripping portions 123 seal the edges 106a, 106b, 107a, 107b of the apparatus 100”’ so as to prevent air from escaping from the space between the arms 101a, 101b (and thus could equally be considered sealing portions of the apparatus).

In addition to the gripping portions 123, the apparatus 100”’ includes four intermediate sealing portions 124. Each sealing portion 124 is in the form of an elongate resilient member and is disposed between a steam outlet 113 and an airflow outlet 120a, 120b or extraction opening 140a, 140b. In this way, the sealing portions 124 seal between the airflow outlets 120a, 120b and the steam outlets 113 (to prevent mixing of air and steam).

Figures 6 to 8 illustrate variations of the above described embodiments in which the external fluid outlets are adapted so as to provide different styling and/or drying functions. In Figure 6, one of the arms 101 of the apparatus includes an external fluid outlet 145’ that is configured to discharge air across the trailing opening 146 of the apparatus (i.e. in a direction perpendicular to an axis (i.e. movement axis) that extends between the trailing 146 and leading 147 openings). In particular, the external fluid outlet 145’ is in the form of a slot that is provided on a raised trailing portion 149 of one of the arms. In particular, the raised portion 149 represents a portion of the inner surface of the arm that extends beyond the hair-receiving space (i.e. so as to project above the other arm 101). Accordingly, the external fluid outlet 145’ is configured to discharge fluid across or through a tress of hair received in the hair-receiving space (in particular a portion of the tress of hair that extends out of the hair-receiving space).

The positioning of the external fluid outlet 145’ of Figures 6 may allow it to push shorter hairs in a tress of hair behind longer hairs in the tress of hair when a tress of hair is passed through the hair-receiving space (and the apparatus 100 is moved along the tress). This may reduce fly- aways in the styled hair (i.e. hairs sticking outwardly form the tress of hair), which may provide a shinier, smoother appearance.

As may be appreciated, the external fluid outlet 145’ could otherwise be arranged to discharge airflow across the leading opening 147, or the apparatus 100 could include two external fluid outlets 145’ each at the leading 147 and trailing 146 openings.

In Figure 7, the external fluid outlet 145” is arranged to make use of the Coanda effect. In particular, the housing 104 of each arm has a curved surface (each housing 104 therefore having a generally semi-circular shaped cross-section). The external fluid outlet 145” is in the form of a slot that is arranged at a trailing portion of one of the arms 101 (adjacent the trailing opening 146), and is configured to direct fluid flow along the curve of the housing 104 (i.e. in a circumferential direction about the arms 101). In particular, the external fluid outlet 145” directed fluid flow in a direction that is tangential to the curve of the housing 104, and is positioned so as to be adjacent to the surface of the housing 104.

Accordingly, due to the Coanda effect, the fluid discharged from the external fluid outlet 145” attaches to the housing 104 and follows a curved path (extending generally circumferentially about the arm 101). In use, this can help to retain a tress of hair against the curved surface of the housing 104. Accordingly, the fluid flow can facilitate wrapping of hair about the arms 101, while concurrently styling the hair. Likewise, directing the fluid along the wrapped tress of hair (rather than through) may allow more efficient styling (because the fluid may be adjacent to the hair for a longer length of the flow path). In some cases, for example, where a tress of hair is not necessarily wrapped about the arms 101 , the retention of the tress of hair against the housing by the fluid flow can help to apply tension to the tress of hair. In such circumstances, the fluid flow can also help to push shorter hairs behind longer hairs in the tress of hair (partly facilitated by the fact that longer hairs are more readily retained on the housing), so as to reduce fly-aways and provide a smoother, shinier appearance.

As may be appreciated, in other embodiments, each arm 101 may include such an external fluid outlet 145”, both outlets 145” arranged to direct fluid about the arm 101 in the same direction (i.e. clockwise or anti-clockwise).

In Figure 7, the external fluid outlet 145” is arranged to direct a fluid flow in a direction that is parallel to an axis (i.e. a movement axis) extending between the leading 147 and trailing 146 openings (i.e. downwards as illustrated). To provide this, the external fluid outlet 145” is positioned at a leading portion of one of the arms 101 and directed fluid away from the arm 101. Accordingly, in use, fluid is directed from the external fluid outlet 145” along a tress of hair received in the hair-receiving space (in this embodiment, towards a distal end of the tress of hair). The fluid discharged by the outlet 145” may therefore pre-treat the hair before it passes between the arms 101 (for further treatment by internal outlets).

As may be appreciated, alternatively or additionally, an external fluid outlet 145” (facing in an opposite direction) may be provided at a trailing portion of one of the arms 101. Fluid discharged from such an external fluid outlet 145” would post-treat hair passing between the arms 101 (e.g. could dry the hair after passing between the arms 101).

The exemplary embodiments set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.

Thus, for example, the illustrated embodiments are hair straightening devices. However, the apparatus may take other forms. For example, the apparatus may be in the form of a heated brush (e.g. may include a single housing/arm with a single hair-facing surface).

For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purposes of improving the understanding of a reader. The inventors do not wish to be bound by any of these theoretical explanations.

Throughout this specification, including the claims which follow, unless the context requires otherwise, the word “comprise” and “include”, and variations such as “comprises”, “comprising”, and “including” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent “about,” it will be understood that the particular value forms another embodiment. The term “about” in relation to a numerical value is optional and means for example +/- 10%.