GB2613800A

GB2613800A - A haircare appliance

Info

Publication number: GB2613800A
Application number: GB2118085.6A
Authority: GB
Inventors: Brann Adam; Haruna Waters Imhasly Nathan
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2021-12-14
Filing date: 2021-12-14
Publication date: 2023-06-21
Also published as: WO2023111507A1; GB202118085D0

Abstract

An attachment for a haircare appliance comprising an air inlet 202, an air outlet 204, a curved surface 206 adjacent to the air outlet and a switching member 208 for directing airflow from the outlet wherein in a first position airflow passes a first side of the switching member and the curved surface to attach to it and in a second position airflow passes a second side and is directed away from the curved surface. The device is designed to smooth hair by attracting or pushing it away from the curved surface 206. The switching member may pivot with the curved surface and be biased to a position. A sensor may be used to automatically activate the switch based on a parameter. The device is designed to address problems with shorter or broken flyaway hair.

Description

A HAIRCARE APPLIANCE

Field of the Invention

The present invention relates to a haircare appliance, and an attachment for a haircare appliance.

Background of the Invention

Haircare appliances are typically used to dry and style hair. Where haircare appliances are used to style hair to create a smooth appearance, the presence of shorter or broken hairs, sometimes referred to as flyaways, may impact on the desired smooth appearance.

Summary of the Invention

According to a first aspect of the present invention there is provided an attachment for a haircare appliance, the attachment comprising an air inlet, an air outlet, a curved surface adjacent to and downstream of the air outlet, and a switching member for directing airflow exiting the air outlet, the switching member switchable relative to the air outlet between a first switch position, in which airflow exiting the air outlet passes between a first side of the switching member and the curved surface and attaches to the curved surface, and a second switch position, in which airflow exiting the air outlet passes over a second, opposing side of the switching member and is directed away from the curved surface.

The attachment according to the first aspect of the present invention may be advantageous as the inventors of the present application have determined that directing airflow across the curved surface may generate a negative pressure region adjacent to the curved surface which attracts long hairs toward the curved surface, with the airflow interaction with hair also pushing shorter hairs away from the curved surface. This may result in shorter hairs being pushed through the longer hairs, for example through the longer hairs toward the side of hair facing a user's head, such that a smooth finish is provided.

The attachment according to the first aspect of the present invention may be advantageous as the attachment can be used in two different modes depending on the position of the switching member and thus the direction of airflow exiting the air outlet. For example, the switching member may be placed in the first switch position to smooth hair and in the second switch position to dry hair.

The air outlet may comprise a rectangular slot, which may provide a more laminar airflow across the curved surface and allow a greater area of hair to be contacted by the airflow across the curved surface and thus styled by the attachment.

The air outlet may be a fixed air outlet, for example an air outlet of fixed cross-sectional area, length and/or width. This may ensure that airflow characteristics of the attachment are constant for a given flow rate of airflow generated by the airflow generator. When the switching member is in the first switch position, this may ensure a constant airflow along a length of the air outlet, allowing more aligned hair smoothing by the attachment. This may also provide a simpler attachment with fewer moving parts, and hence a reduced risk of failure, compared to an attachment with a variable air outlet.

The curved surface may comprise a Coanda surface, for example a convex surface along which airflow is attached as a result of the Coanda effect in use.

The curved surface may be substantially smooth and uninterrupted in form, for example free of projections and/or recesses. This may enable hair to wrap around the curved surface in use The curved surface may comprise a radius of curvature in the region of lOmm to 60mm. The applicant has found that such a radius of curvature may be particularly effective in generating an airflow along the curved surface that results in a first force to attract hair toward the curved surface, and a second force to push hair away from the curved surface.

The curved surface may comprise a substantially constant radius of curvature.

With the switching member in the first switch position, airflow exiting the air outlet may generate a first force to attract hair toward the curved surface, and a second force to push hair away from the curved surface. This may result in shorter hairs being pushed through the longer hairs, for example through the longer hairs toward the side of hair facing a user's head, such that a smooth finish is provided.

In use, substantially all of the airflow exiting the air outlet may pass between the first side of the switching member and the curved surface when the switching member is in the first switch position. This may result in a smoother finish to the user's hair.

In use, airflow may contact the first side of the switching member when the switching member is in the first switch position This may allow the switching member to better direct the airflow towards the curved surface The first side of the switching member may comprise an arced surface for turning airflow toward the curved surface. That is, the switching member may be concave to help align airflow as it turns from the air outlet to flow across the curved surface. This may help to attach the airflow to the curved surface.

In use, substantially all of the airflow exiting the air outlet may pass over the second side of the switching member and be directed away from the curved surface when the switching member is in the second switch position. That is, airflow exiting the air outlet does not attach to the curved surface when the switching member is in the second switch position This may result in a greater airflow interacting with the user's hair to dry the hair.

In use, airflow may contact the second side of the switching member when the switching member is in the second switch position. This may help to direct the airflow in the desired direction.

The attachment may comprise a flat surface adjacent to and extending rearwardly from air outlet. Where a non-flat surface, is provided extending rearwardly from the air outlet, the smooth finish provided when the switching member is in the first switch position can be disturbed as the attachment is moved relative to the hair in use, as may typically be the case during styling operations. Where a rough surface, for example a surface comprising projections such as bristles or the like, is provided extending rearwardly from the air outlet, such a rough surface may interrupt hair that has already been smoothed by airflow from the air outlet as the attachment is moved relative to the hair in use when the switching member is in the first switch position. By providing a curved surface adjacent to and downstream of the air outlet, and a flat surface adjacent to and extending rearwardly from the air outlet, a smooth hair finish may be created and maintained as the attachment is moved relative to hair by a user in use when the switching member is in the first switch position.

The attachment may comprise a pair of guide walls for guiding airflow along the curved surface, the pair of guide walls upstanding from the curved surface. By providing a pair of guide walls extending outwardly from the curved surface ambient air may be inhibited from impacting on a region of negative pressure generated by airflow flowing along the curved surface in use when the switching member is in the first switch position, and may result in increased attraction of hair toward the curved surface compared to, for example, a similar arrangement that does not utilise guide walls.

The switching member may be switchable between the first and second switch positions about a pivot. This may provide a simple and reliable way of moving the switching member, which may avoid catching of the switching member on other surfaces within the attachment during movement of the switching member, which may occur in an example in which the switching member is slid between the first and second switch positions.

The switching member may extend in a direction from the pivot substantially towards the air outlet. The pivot may be positioned downstream from the air outlet so that the switching member extends from the pivot in a substantially upstream direction. The pivot

S

may be positioned at or near an edge of the switching member such that substantially all of the switching member is positioned between the pivot and the air outlet.

The switching member may form a seal with a first edge of the air outlet when the switching member is in the first switch position and form a seal between with a second, opposing edge of the air outlet when the switching member is in the second switch position, the second edge of the air outlet being closer to the curved surface than the first edge. This may reduce air loss as air exits the air outlet, thereby increasing the performance of the attachment compared to an attachment whereby the switching member does not form a seal with an edge of the air outlet.

The switching member may be elongate, having a length at least as long as a length of the air outlet This may reduce air loss as air exits the air outlet, thereby increasing the performance of the attachment.

The switching member may comprise a single body, for example a single monolithic component. This may provide a simpler arrangement than, for example, a corresponding arrangement where the switching member comprises multiple bodies, which may reduce component count and cost, and may reduce a risk of failure in use.

The curved surface may be movable relative to the air outlet between a first ramp position and a second ramp position, and movement of the curved surface from the first ramp position to the second ramp position may cause the switching member to switch between the first and second switch positions. This may allow a user to switch the switching member between the first and second switch positions without touching the switching member, for example without needing to place their hand in the airflow exiting the air outlet. This may also, for example, allow a user to switch the switching member between the first and second switch positions by pushing the attachment against their head in use to move the curved surface from the first ramp position to the second ramp position.

Movement of the curved surface from the second ramp position to the first ramp position may not cause the switching member to switch between the first and second switch positions. For example, the attachment may be configured such that movement of the curved surface from the first ramp position to the second ramp position causes the switching member to switch from the second switch position to the first switch position, but movement of the curved surface from the second ramp position to the first ramp position does not cause the switching member to switch from the first switch position to the second switch position. This may help to keep the switching member in the first switch position during hair styling, even in the event that the curved surface is knocked or pushed from the second ramp position to the first ramp position during use of the attachment, so that hair styling completed with the first ramp position is not undone by inadvertent switching of the switching member to the second switch position.

The curved surface and the switching member may be rigidly connected. This may allow an efficient transfer of force from the curved surface to the switching member to switch the switching member between the first and second switch positions. This may also help to ensure that the curved surface is in the correct position relative to the switching member and the air outlet to increase the styling performance of the attachment, particularly when the switching member is in the first switch position. This may also allow a user to more clearly identify a mode in which the attachment is configured, by noting a position of the curved surface relative to the air outlet.

The switching member and the curved surface may comprise a single body. This may provide a simpler arrangement than, for example, a corresponding arrangement comprising multiple bodies, which may reduce component count and cost, and may reduce a risk of failure in use.

The curved surface may be biased towards the first ramp position. This may help to ensure that the curved surface is in the correct position relative to the air outlet to increase the styling performance of the attachment, particularly when the switching member is in the first switch position.

The switching member may be biased toward the first and second switch positions by airflow exiting the air outlet. This may help to retain the switching member in the first and second switch positions without the need for an additional retaining force, or in combination with a lesser retaining force compared to an attachment in which the airflow does not bias the switching member to the first and second switch positions. For example, in use, when the switching member is in the first switch position, airflow exiting the air outlet may apply a force to the first side of the switching member in such a direction that the switching member is forced away from the curved surface, and when the switching member is in the second switch position, airflow exiting the air outlet may apply a force to the second side of the switching member in such a direction that the switching member is forced toward the curved surface.

The attachment may comprise a retention mechanism for retaining the switching member in one of the first and second switch positions in the absence of an applied force to the switching member by a user of the haircare appliance. This may be advantageous as the switching member is retained in the first or second switch position by the retention mechanism in the absence of an applied force to the switching member by a user of the attachment, allowing the user to change an orientation of the attachment without the switching member switching between the first and second switch positions under, for example, gravity. This may enable the user to style curls into the hair by, for example, rotating the attachment.

The retention mechanism may help a user to use the attachment in a variety of orientations without the switching member switching between the first and second switch positions The retention mechanism may be arranged to retain the switching member in the other of the first and second switch positions upon application of an applied force to the switching member by a user of the attachment. This may provide assurance to the user that the switching member is positioned correctly. This may also ensure a correct direction of airflow exiting the air outlet.

The retention mechanism may comprise magnetic elements configured to retain the switching member in the first and second switch positions. At least some of the magnetic elements may be electrically controllable such that their polarity may be reversed so as to selectively attract or repel the switching member. The use of magnets may reduce the number of moving parts required to retain the switching member in the first and second switch positions.

The retention mechanism may comprise a biasing element for biasing the switching member to the first and second switch positions. For example, the retention mechanism may comprise a bi-stable spring that is stable when the switching member is in the first and second switch positions. The biasing element may help to ensure the switching member properly reaches the first and second switch positions to ensure proper directing of airflow. The biasing element may also increase the force required to switch the switching member between the first and second switch positions which may help to prevent inadvertent movement of the switching member.

An applied force for switching the switching member between the first and second switch positions may be a contact force applied to the switching member. For example, a user may apply the applied force directly onto the switching member. This may provide the advantage that a user can clearly identify that the switching member has been moved because the user has applied a force directly to the switching member.

The attachment may comprise a user interface operable by a user to switch the switching member between the first switch position and the second switch position The user interface may, for example, comprise one or more of a handle, high friction gripping surface, knob, push button, toggle or touch screen. This may aid in simplifying a process for a user to switch the switching member between the first and second switch positions For example, the user interface may comprise a handle positioned on the switching member and movable by a user to switch the switching member between the first switch position and the second switch position.

The attachment may comprise a sensor for detecting a parameter of the attachment and outputting a signal indicative of the parameter, and a switching system for automatically switching the switching member between the first and second switch positions in response to a determination that the signal meets a predetermined criterion. This may allow the attachment to be switched between different operating modes during use of the attachment and without input from the user.

The sensor may be arranged to detect a distance between the attachment and a user's head.

A user typically holds a haircare appliance at a greater distance from their head when drying their hair compared to when styling their hair. Accordingly, for example, the switching system may automatically cause the switching member to switch to the first switch position when the distance between the attachment and the user's head is determined to be below a threshold distance.

The sensor may be arranged to detect an input from a user indicative of a desired operating mode of the attachment Accordingly, for example, the switching system may automatically cause the switching member to switch to the first switch position if, for example, it is determined that a styling mode has been selected, and to the second switch position if, for example, it is determined that a drying mode has been selected. This may allow the attachment to be switched between different operating modes without a user needing to place their hands near to the air outlet.

The sensor may be arranged to detect a temperature of airflow exiting the air outlet Accordingly, for example, the switching system may automatically cause the switching member to switch to the first switch position when a temperature of the airflow exiting the air outlet is determined to be below a threshold temperature.

The determination that the signal meets the predetermined criterion may be performed by a controller configured to receive the signal. The controller may be comprised in the switching system.

The switching system may comprise any suitable means for automatically switching the switching member between the first and second switch positions. For example, the switching system may comprise a servo motor for driving motion of the switching member between the first and second switch positioned about a pivot. For example, the switching system may comprise one or more electrically controllable magnetic elements for selectively attracting and/or repelling the switching member.

The attachment may comprise a plurality of sensors for detecting a plurality of different parameters of the attachment. The controller may be configured to receive a signal from each of the plurality of sensors and determine whether the switching member should be switched from its first or second switch position to the other of the first or second switch position The attachment may comprise an alert module configured to alert a user that the switching member is in the first switch position and/or the second switch position. This may enable a user to know which mode the attachment is operating in. For example, the alert module may provide a first indicium to indicate when the switching member is in the first switch position and a second, different indicium when the switching member is in the second switch position. The alert module may comprise at least one of a haptic feedback module, a visual indicium, and an aural indicium. This may ensure that an alert is provided to a user irrespective of whether the attachment is visible to the user.

According to a second aspect of the present invention there is provided a haircare appliance comprising an air inlet, an air outlet, a curved surface adjacent to and downstream of the air outlet, a switching member for directing airflow exiting the air outlet, and an airflow generator for generating an airflow from the air inlet to the air outlet, the switching member switchable relative to the air outlet between a first switch position, in which airflow exiting the air outlet passes between a first side of the switching member and the curved surface and attaches to the curved surface, and a second switch position, in which airflow exiting the air outlet passes over a second, opposing side of the switching member and is directed away from the curved surface.

The haircare appliance may comprise a heater for heating the airflow. This may provide increased styling flexibility. The heater may be configured to operate at a particular temperature dependent on whether the switching member is in the first switch position or the second switch position. For example, the heater may be configured to operate at a first temperature when the switching member is in the first switch position and a second, higher temperature when the switching member is in the second switch position. The inventors of the present application have determined that airflow of a lower temperature than an airflow temperature typically used for drying hair is advantageous for providing the smooth finish described above during styling without inadvertent hair curling.

The haircare appliance may comprise a handle unit within which the airflow generator is housed, and an attachment according to the first aspect of the present invention, the attachment releasably attachable to the handle unit. Providing a removable attachment may allow the functionality of the attachment described herein to be selectively provided by a user.

Optional features of aspects of the present invention may be equally applied to other aspects of the present invention, where appropriate

Brief Description of the Drawings

Figure 1 is a schematic view illustrating a haircare appliance according to the present invention; Figure 2 is a schematic cross-sectional view through a handle unit of the haircare appliance of Figure 1, Figure 3 is a schematic perspective view of an embodiment of an attachment for the haircare appliance of Figure 1; Figure 4 is a schematic view illustrating forces created by airflow through the attachment for the haircare appliance of Figure 1 in use; Figure 5 is a schematic perspective view of an embodiment of an attachment for the haircare appliance of Figure 1, illustrating the attachment in a styling mode; Figure 6 is a schematic cross-sectional view of the attachment of Figure 5, illustrating the attachment in the styling mode; Figure 7 is a schematic perspective view of the attachment of Figure 5, illustrating the attachment in a drying mode; Figure 8 is a schematic cross-sectional view of the attachment of Figure 5, illustrating the attachment in the drying mode, Figure 9 is a schematic perspective view of another embodiment of an attachment for the haircare appliance of Figure 1, illustrating the attachment in a drying mode, Figure 10 is a schematic perspective view of the attachment of Figure 9; Figure 11 is a schematic perspective view of the attachment of Figure 9, illustrating the attachment in a styling mode; Figure 12 is a schematic cross-sectional view of the attachment of Figure 9, illustrating the attachment in the drying mode; Figure 13 is a schematic cross-sectional view of the attachment of Figure 9, illustrating the attachment in the styling mode; and Figure 14 is a schematic cross-sectional view of another embodiment of an attachment for the haircare appliance of Figure 1, illustrating the attachment in a drying mode.

Detailed Description of the Invention

A haircare appliance according to the present invention, generally designated 10, is shown schematically in Figure 1.

The haircare appliance 10 comprises a handle unit 11, and an attachment 100 removably attachable to the handle unit 11. The handle unit 11 comprises a handle portion 12, a head portion 14, an airflow generator 16 and a heater 18.

The handle portion 12 is generally cylindrical and hollow in form and houses the airflow generator 16. The handle portion 12 has an air inlet 20 in the form of a plurality of perforations at a first end 22 of the handle portion 12.

The head portion 14 is generally cylindrical and hollow in form, and is disposed at a second end 24 of the handle portion 12, with a central axis of the head portion 14 orthogonal to a central axis of the handle portion 12 such that the handle unit 11 is generally T-shaped in form. The head portion 14 houses the heater 18. The head portion 14 comprises a bore 26 through which air is entrained, and an air outlet 28. The air outlet 28 is generally annular in form about a periphery of the bore 26.

The haircare appliance 10 comprises a control unit 30. The control unit 30 may be comprised in the attachment 100 or the handle unit 11. In the embodiment shown in Figures 1 and 2, the control unit 30 is comprised in the handle unit 11. The control unit 30 comprises electronic circuitry for a user interface 32 and a control module 34. The user interface 32 is provided on an outer surface of the handle unit 11, and is used to power on and off the haircare appliance 10, to select a flow rate (for example high, medium and low), and to select an airflow temperature (for example hot, medium or cold).

The user interface may comprise a plurality of sliding switches, but other forms of user interface 32, for example buttons, dials or touchscreens, are also envisaged The control module 34 is responsible for controlling the airflow generator 16, and a heater (not shown) in response to inputs from the user interface 32. For example, in response to inputs from the user interface 32, the control module 34 may control the power or the speed of the airflow generator 16 in order to adjust the airflow rate of the airflow, and the power of the heater in order to adjust the temperature of the airflow.

An embodiment of the attachment 100 is illustrated in Figure 3. Other embodiments of the attachment will be described in more detail hereinafter and are shown, for example, in Figures 5-13. The attachment 100 comprises an air inlet 102, an air outlet 104 (more clearly shown as air outlet 204 in Figure 6, for example), a curved surface 106 adjacent to and downstream of the air outlet 102, and a switching member 108 for directing airflow exiting the air outlet 104. The switching member 108 is switchable between a first switch position (for example, as shown in Figures 3, 5, 6, 11 and 13) and a second switch position (for example, as shown in Figures 7, 8, 9 and 12). In the first switch position, airflow exiting the air outlet 104 passes between a first side (not shown in Figure 3) of the switching member 108 (more clearly shown as first side 210 in Figure 6, for example) and the curved surface 106 and attaches to the curved surface 106. In the second switch position, airflow exiting the air outlet 104 passes over a second, opposing side 112 of the switching member 108 arid is directed away from the curved surface 106.

In use, the attachment 100 is attached to the handle unit 11. The airflow generator 16 generates an airflow from the air inlet 20 of the handle unit 11 to the air outlet 28 of the handle unit 11, such that airflow passes from the air outlet 28 of the handle unit 11 to the air inlet 102 of the attachment 100. Airflow flows from the air inlet 102 of the attachment toward the air outlet 104. Airflow exits the attachment 100 via the air outlet 104 and passes over the curved surface 106 when the switching member 108 is in the first switch position and is directed away from the curved surface 106 when the switching member 108 is in the second switch position.

Accordingly, the haircare appliance 10 is operable in different modes. In a first, styling mode, the switching member 108 is positioned in the first switch position. In a second, drying mode, the switching member 108 is positioned in the second switch position.

The inventors of the present application have found that, with the haircare appliance 10 in the styling mode, airflow attaches to the curved surface 106 via the Coanda effect. The interaction of forces is illustrated schematically in Figure 4. When a tress of hair is brought into the vicinity of the attachment 100, long hairs of the tress are attracted to, and at least partially wrapped about, the curved surface 106 by a force F PULL, as a result of a negative pressure region generated by the airflow over the curved surface 106. However, the pressure gradient across the tress also results in a force, F PUSH, which causes some airflow to pass directly through the tress. Due to the location of this force relative to the curved surface 106 and the rest of the tress, shorter hairs are only held loosely at this point compared to longer hairs which are held in place on the curved surface 106. The shorter hairs are blown through the tress toward a user's head, whilst the longer hairs remain in place on the outside of the tress, i.e. the portion of the tress facing away from the user's head. This provides a smooth finish for hair following interaction with the haircare appliance 10 when the switching member 108 is in the first switch position.

This effect can be optimised by appropriate modification of the geometries and parameters described herein. One such parameter that may provide increased effectiveness is the velocity of airflow at the air outlet 104 of the attachment 100. In particular, too great a velocity may result in shorter hairs sticking to the curved surface 106 and hence not being pushed away through longer hairs, whilst too low a velocity may not be sufficient to attract longer hairs to the curved surface 106 in the first instance. The applicant has determined that a velocity in the region of 30m/s to 45m/s may be particularly effective in generating an airflow along the curved surface 106 that results in a first force that is sufficient to attract relatively long hair toward the curved surface 106 whilst also generating a second force to push relatively short hair away from the curved surface 102 In a presently preferred embodiment, the velocity of airflow at the air outlet 104 is in the region of 35m/s.

Another parameter that may provide increased efficacy for smoothing hair in the manner described above is a ratio of the velocity of airflow at the air outlet 104 to a flow rate of airflow generated by the airflow generator 16. In the embodiments of Figures 5 to 13, the ratio is in the region of 2.14 to 5.63, and in a particularly preferred embodiment the ratio is in the region of 2.89. The applicant has found that such a ratio may be particularly effective in generating an airflow along the curved surface 106 that results in a first force that is sufficient to attract relatively long hair toward the curved surface 106, whilst also generating a second force to push relatively short hair away from the curved surface 106.

Another parameter that may provide increased efficacy for smoothing hair in the manner described above is a ratio of flow rate of airflow generated by the airflow generator 16 to an open cross-sectional area of the air outlet 104. In the embodiments of Figures 5 to 13, the ratio is in the region of 0.01 to 010, and in a particularly preferred embodiment the ratio is in the region of 0.04. The applicant has found that such a ratio may be particularly effective in generating an airflow along the curved surface 106 that results in a first force that is sufficient to attract relatively long hair toward the curved surface 106, whilst also generating a second force to push relatively short hair away from the curved surface 106.

A further parameter that may provide increased efficacy for smoothing hair in the manner described above is a ratio of a radius of curvature of the curved surface 106 to the velocity of airflow at the air outlet 104. In the embodiments of Figures 5 to 13, the ratio is in the region of 0.33 to 2.00, and in a particularly preferred embodiment the ratio is in the region of 0.57. The applicant has found that such a ratio may be particularly effective in generating an airflow along the curved surface 106 that results in a first force that is sufficient to attract relatively long hair toward the curved surface 106, whilst also generating a second force to push relatively short hair away from the curved surface 106.

Another parameter that may provide increased efficacy for smoothing hair in the manner described above is a ratio of a radius of curvature of the curved surface 106 to an arc length of the curved surface 106. In the embodiments of Figures 5 to 13, the ratio is in the region of 0.04 to 0.63, and in a particularly preferred embodiment the ratio is in the region of 0.18. The applicant has found that such a ratio may be particularly effective in generating an airflow along the curved surface 106 that results in a first force that is sufficient to attract relatively long hair toward the curved surface 106, whilst also generating a second force to push relatively short hair away from the curved surface 106.

A periphery of the air inlet 102 comprises attaching features (not shown) for releasably attaching the attachment 100 to the handle unit 11. The attaching features may take many forms, are not pertinent to the present invention, and so will not be described for the sake of brevity.

The switching member 108 is switchable between the first and second switch positions about a pivot 114 such that the switching member 108 rotates about the pivot 114. It will be appreciated that in other embodiments, the switching member 108 may move between the first and second switch positions in any suitable way, such as sliding of the switching member 108 relative to the air outlet 104.

The pivot 114 is positioned downstream from the air outlet 104 and the switching member 108 extends from the pivot 114 in a substantially upstream direction towards the air outlet 104.

With the switching member 108 in the first switch position, a seal is formed between the switching member 108 and a first edge (not shown in Figure 3) of the air outlet 104 (more clearly shown as first edge 216 in Figure 6, for example). The first edge is at a maximal distance of the air outlet 104 from the curved surface 106. As such, in use, airflow flows between the first side of the switching member 108 and the curved surface 106 for use in the styling mode. The first side of the switching member has an arced surface for turning airflow toward the curved surface (as best shown in Figures 6, 8, 11 and 12 with reference to sides 210 and 310).

With the switching member 108 in the second position, a seal is formed between the switching member 108 and a second edge (not shown in Figure 3) of the air outlet 104 (more clearly shown as second edge 218 in Figure 8, for example). The second edge is at a minimal distance of the air outlet 104 from the curved surface 106. As such, in use, airflow flows over the second side 112 of the switching member 108 and away from the curved surface 106 for use in the drying mode.

The switching member 108 is elongate, having a length at least as long as a length of the air outlet 104.

A pair of guide walls 134 are disposed on opposing edges of the curved surface 106 and extend downstream from the air outlet 104. The guide walls 134 are upstanding from the curved surface 106 and extend along the full arc length of the curved surface 106. The guide walls 134 have a height substantially corresponding to a height of the air outlet 104 and have a constant height along their length. The guide walls 134 effectively create an airflow channel, with the pair of guide walls 134 acting as walls of the channel, and the curved surface 106 acting as a bed of the channel. The guide walls 134 inhibit ambient air from interacting with airflow flowing along the curved surface 106 in use, which may maintain the negative pressure region created by airflow flowing along the curved surface 106.

Whilst depicted in Figure 3 as having guide walls 134 of constant height along the curved surface 106, it has been found that the guide walls 134 may be most effective in the region of the air outlet 104. In alternative embodiments, the attachment 100 has guide walls that decrease in height in a direction away from the air outlet 104. Thus, less material may be required to form the guide walls than, for example, guide walls 134 of a constant height.

An end wall 136 is positioned at an edge of the curved surface 106 distal from the air outlet 104 and extends between the guide walls 134. The end wall 136 prevents airflow from travelling toward the handle portion 12 of the handle unit 11 when the attachment 100 is attached to the handle unit 11 in use.

In use, the switching member 108 is sw tchable between the first and second switch positions upon application of a force by a user to the switching member 108. The force may be applied by a user's hand. It will be appreciated that in other embodiments, the attachment 100 may comprise a user interface operable by a user, such as a handle, for switching the switching member 108 between the first and second switch positions. It will be appreciated that in still other embodiments, the attachment 100 may comprise a system for automatically switching the switching member 108 between the first and second switch positions, for example in response to a signal emitted from a sensor comprised in the attachment 100 or the handle unit 11.

In use, airflow exiting the air outlet 104 and passing over the switching member 108 asserts a force onto the first side or second side 112 of the switching member 108 to retain the switching member 108 in the first or second switch position. In will be appreciated that in other embodiments, the attachment 100 may comprise a retention mechanism for retaining the switching member in the first and/or second switch position. The retention mechanism may take many forms, for example may comprise magnetic elements or a bistable spring to retain the switching member in the first and/or second switch position.

Further embodiments of attachments 200, 300 for use with the haircare appliance 10 are shown in Figures 5 to 13 Features common to the attachment 100 share the same reference numeral, but increased by 100 or 200, respectively.

An embodiment of an attachment 200 is illustrated in Figures 5 to 8. In Figures 5 and 6, the attachment 200 is configured for use with the haircare appliance 10 in a styling mode.

That is, the switching member 208 is in the first switch position. In Figures 7 and 8, the attachment 200 is configured for use with the haircare appliance 10 in a drying mode That is, the switching member 208 is in the second switch position.

For this embodiment, the curved surface 206, the guide walls 234 and the end wall 236 will be collectively referred to as a ramp 205. The curved surface 206, the guide walls 234 and the end wall 236 form a single rigid body.

The ramp 205 and the switching member 208 are not movable relative to one another. That is, the ramp 205 and the switching member 208 are rigidly connected. The ramp 205 is movable relative to the air outlet 204 between a first ramp position, as shown in Figures and 6, and a second ramp position, as shown in Figures 7 and 8. The ramp 205 and the switching member 208 are movable relative to the air outlet 204 about a pivot 214.

With the switching member 208 in the first switch position, the second side 212 of the switching member 208 contacts and forms a seal with the first edge 216 of the air outlet 204 such that, in use, airflow exiting the air outlet 204 passes between the switching member 208 and the curved surface 206 and attaches to the curved surface 206, as denoted by the dashed arrows in Figure 6. With the switching member 208 in the first switch position, the ramp 205 is positioned relative to the air outlet 204 so that airflow exiting the air outlet 204 and directed by the switching member 208 attaches to the curved surface 206 so that a user can perform a styling operation as described above.

With the switching member 208 in the second switch position, the first side 210 of the switching member 208 contacts and forms a seal with the second edge 218 of the air outlet 204 such that, in use, airflow exiting the air outlet 204 passes over the first side 210 of the switching member 208 and is directed away from the curved surface 206, as denoted by the dashed arrows in Figures 7 and 8.

In use, the switching member 208 is moveable between the first and second switch positions upon application of a force by a user to the ramp 205. The force may be applied by a user' s hand or, for example, by pressing the attachment 200 against a user's head. It will be appreciated that in other embodiments, the attachment 200 may comprise a user interface operable by a user, such as a handle, for switching the switching member 208 between the first and second switch positions. It will be appreciated that in still other embodiments, the attachment 200 may comprise a system for automatically switching the switching member 208 and ramp 205 between the first and second switch positions and first and second ramp positions, respectively, for example in response to a signal emitted from a sensor comprised in the attachment 200 or the handle unit 11.

In use, airflow exiting the air outlet 204 and passing over the switching member 208 asserts a force onto the first or second side 210, 212 of the switching member 208 to retain the switching member in the first or second switch position and thus retain the ramp 205 in the corresponding first or second ramp position. In will be appreciated that in other embodiments, the attachment 200 may comprise a retention mechanism for retaining the switching member in the first and/or second switch position. The retention mechanism may take many forms, for example may comprise magnetic elements or a bi-stable spring to retain the switching member in the first and/or second switch position.

An embodiment of an attachment 300 is illustrated in Figures 9 to 13. In Figures 11 and 13, the attachment 300 is configured for use with the haircare appliance 10 in a styling mode. That is, the switching member 308 is in the first switch position. In Figures 9 and 12, the attachment 300 is configured for use with the haircare appliance 10 in a drying mode. That is, the switching member 308 is in the second switch position.

For this embodiment, the curved surface 306, the guide walls 334 and the end wall 336 will be collectively referred to as a ramp 305 The curved surface 306, the guide walls 334 and the end wall 336 form a single rigid body.

The ramp 305 is movable relative to the air outlet 304 between a first ramp position, as shown in Figures 9, 11, 12 and 13, and a second ramp position, as shown in Figure 10.

The ramp 305 and the switching member 308 are movable relative to the air outlet 304 about a pivot 314. The ramp 305 and the switching member 308 are movable relative to one another.

The ramp 305 and the switching member 308 are connected such that movement of the ramp 305 from the first ramp position to the second ramp position causes the switching member 308 to switch from the second switch position to the first switch position, but movement of the ramp 305 from the second ramp position to the first ramp position does not cause the switching member 308 to switch from the first switch position to the second switch position.

With the switching member 308 in the second switch position, the first side 310 of the switching member 308 contacts and forms a seal with the second edge 318 of the air outlet 304 such that, in use, airflow exiting the air outlet 304 passes over the first side 310 of the switching member 308 and is directed away from the curved surface 306, as denoted by the dashed arrows in Figures 9 and 12.

Upon application of a force to the ramp 305, for example in the direction denoted by arrow A in Figure 10, the ramp 305 is moved from the first ramp position to the second ramp position, causing the switching member 308 to switch from the second switch position to the first switch position, as illustrated in Figures 9-11. Upon withdrawal of the force, the ramp 305 is returned to the first ramp position and the switching member 308 remains in the first switch position, as illustrated in Figure 11. In use, the haircare appliance 10 is therefore switched from the drying mode to the styling mode by application of the force to the ramp 305 With the switching member 308 in the first switch position, the second side 312 of the switching member 308 contacts and forms a seal with the first edge 316 of the air outlet 304 such that, in use, airflow exiting the air outlet 304 passes between the switching member 308 and the curved surface 306 and attaches to the curved surface 306, as denoted by the dashed arrows in Figures 11 and 13. With the switching member 308 in the first switch position, the ramp 305 is in the first ramp position and is positioned relative to the air outlet 304 so that airflow exiting the air outlet 304 and directed by the switching member 308 attaches to the curved surface 306 so that a user can perform a styling operation as described above.

The ramp 305 is biased to the first ramp position. Any suitable means for biasing the ramp 305 to the first ramp position may be employed and are not pertinent to the present invention, and so will not be described for the sake of brevity.

In use, the switching member 308 is switched from the second switch position to the first switch position upon application of a force by a user to the ramp 305. The force may be applied by a user's hand or, for example, by pressing the attachment 200 against a user's head. It will be appreciated that in other embodiments, the attachment 300 may comprise a user interface operable by a user, such as a handle, for moving the ramp 205 from the first ramp position to the second ramp position. It will be appreciated that in still other embodiments, the attachment 300 may comprise a system for automatically moving the ramp 205 from the first ramp position to the second ramp position, for example in response to a signal emitted from a sensor comprised in the attachment 300 or the handle unit 11.

In use, airflow exiting the air outlet 304 and passing over the switching member 308 asserts a force onto the first or second side 310, 312 of the switching member 308 to retain the switching member in the first or second switch position. In will be appreciated that in other embodiments, the attachment 300 may comprise a retention mechanism for retaining the switching member in the first and/or second switch position. The retention mechanism may take many forms, for example may comprise magnetic elements or a bistable spring to retain the switching member in the first and/or second switch position.

An embodiment of an attachment 400 is schematically illustrated in Figure 14. In Figure 14, the attachment 400 is configured for use with the haircare appliance 10 in a drying mode. That is, the switching member 408 is in the second switch position. The attachment 400 is substantially the same to the attachment 300 described above with reference to Figures 9 to 13. Common features are shown with corresponding reference numerals, albeit increased by 100.

The attachment 400 comprises a system 420 for automatically switching the switching member 408 between the first and second switch positions and a proximity sensor 430 for detecting a distance between the attachment 400 and a user's head. The proximity sensor 430 is arranged to output a signal indicative of a distance between the attachment 400 and the user's head. The proximity sensor 430 in this example is a Time or Flight sensor and is positioned on the curved surface 406 The system 420 comprises a servomotor 422 for applying a switching force to the switching member 408 via the pivot 414, and a controller 424 for controlling the servomotor 422 The controller 424 is arranged to receive the signal from the proximity sensor 430, determine a desired position of the switching member 408 based on the received signal, and to cause the servomotor 422 to switch the switching member 408 between the first and second switch positions if the switching member 408 is not in the desired position. In an example, the servomotor 422 may be arranged to turn a rod or handle protruding from the pivot 414, the rod or handle being connected to the switching member 408.

It will be appreciated that the attachments 100, 200 may also be suitable for use with the system 420.

The haircare appliance 10 may also comprise an alert module 36. The alert module is arranged to alert a user that the switching member 108, 208, 308 is in the first switch position or the second switch position. The alert module 36 comprises one or more of a haptic feedback module, an audible indicium or a visual indicium. In this embodiment the alert module 36 is shown as being in the handle unit 11, but it will be appreciated that in other embodiments the alert module 36 may be comprised in the attachment 100, 200, 300.

Although described herein as embodiments with releasable attachments, embodiments are also envisaged where, rather than the haircare appliance comprising a handle unit and an attachment the haircare appliance is a single-piece unit, for example taking the form of the combined handle unit and attachment previously described.

Claims

Claims 1. An attachment for a haircare appliance, the attachment comprising an air inlet, an air outlet, a curved surface adjacent to and downstream of the air outlet, and a switching member for directing airflow exiting the air outlet, the switching member switchable relative to the air outlet between a first switch position, in which airflow exiting the air outlet passes between a first side of the switching member and the curved surface and attaches to the curved surface, and a second switch position, in which airflow exiting the air outlet passes over a second, opposing side of the switching member and is directed away from the curved surface.
2. An attachment as claimed in Claim I, wherein, with the switching member in the first switch position, airflow exiting the air outlet generates a first force to attract hair toward the curved surface, and a second force to push hair away from the curved surface
3 An attachment as claimed in Claim I or Claim 2, wherein the first side of the switching member comprises an arced surface for turning airflow toward the curved surface.
4. An attachment as claimed in any preceding claim, wherein the switching member is switchable between the first and second switch positions about a pivot, and the switching member extends in a direction from the pivot substantially towards the air outlet.
5 An attachment as claimed in any preceding claim, wherein the switching member forms a seal with a first edge of the air outlet when the switching member is in the first switch position and forms a seal between with a second, opposing edge of the air outlet when the switching member is in the second switch position, the second edge of the air outlet being closer to the curved surface than the first edge.
6 An attachment as claimed in any preceding claim, wherein the curved surface is movable relative to the air outlet between a first ramp position and a second ramp position, and movement of the curved surface from the first ramp position to the second ramp position causes the switching member to switch between the first and second switch positions.
7. An attachment as claimed in Claim 6, wherein the curved surface is biased towards the first ramp position.
8. An attachment as claimed in Claim 6 or Claim 7, wherein movement of the curved surface from the second ramp position to the first ramp position does not cause the switching member to switch between the first and second switch positions.
9. An attachment as claimed in any of claims 1 to 7, wherein the curved surface and the switching member are rigidly connected.
10. An attachment as claimed in any preceding claim, wherein, in use, the switching member is biased toward the first and second switch positions by airflow exiting the air outlet.
11. An attachment as claimed in any preceding claim, comprising a retention mechanism for retaining the switching member in one of the first and second switch positions in the absence of an applied force to the switching member by a user of the haircare appliance.
12. An attachment as claimed in Claim 11, wherein the retention mechanism is arranged to retain the switching member in the other of the first and second switch positions upon application of an applied force to the switching member by a user of the haircare appliance.
13 An attachment as claimed in any preceding claim, comprising a sensor for detecting a parameter of the attachment and outputting a signal indicative of the parameter, and a switching system for automatically switching the switching member between the first and second switch positions in response to a determination that the signal meets a predetermined criterion.
14. An attachment as claimed any preceding claim, comprising a user interface remote from the switching member and operable by a user to switch the switching member between the first switch position and the second switch position.
15. A haircare appliance comprising an air inlet, an air outlet, a curved surface adjacent to and downstream of the air outlet, a switching member for directing airflow exiting the air outlet, and an airflow generator for generating an airflow from the air inlet to the air outlet, the switching member switchable relative to the air outlet between a first switch position, in which airflow exiting the air outlet passes between a first side of the switching member and the curved surface and attaches to the curved surface, and a second switch position, in which airflow exiting the air outlet passes over a second, opposing side of the switching member and is directed away from the curved surface.
16. A haircare appliance as claimed in Claim 15, comprising a handle unit within which the airflow generator is housed, and an attachment releasably attachable to the handle unit, the attachment comprising the air outlet, the curved surface and the switching member.