WO2020025919A1

WO2020025919A1 - Attachment for a handheld appliance

Info

Publication number: WO2020025919A1
Application number: PCT/GB2019/051634
Authority: WO
Inventors: Stephen Courtney
Original assignee: Dyson Technology Limited
Priority date: 2018-08-01
Filing date: 2019-06-13
Publication date: 2020-02-06
Also published as: GB2576015A; CN110786617A; US20210298445A1; GB2576015B; GB201812548D0; CN211154233U

Abstract

An attachment for a hair styling apparatus, wherein the attachment includes an air inlet for receiving airflow from the hair styling apparatus, an elongate slot- shaped air outlet, a duct for conveying air from the air inlet to the air outlet, a bar mounted within the duct and along the length of the air outlet; and a series of comb teeth mounted on the bar. The bar is flexible and enables resilient movement of the comb teeth.

Description

ATTACHMENT FOR A HANDHELD APPLIANCE

FIELD OF THE INVENTION

The present invention relates to an attachment for a handheld appliance, in particular a hair care appliance such as a hot air styling device or hair dryer.

BACKGROUND OF THE INVENTION

In a conventional hot air styling device or hair dryer, the form and velocity of the emitted airflow may be modified by a removable nozzle or attachment. Depending on the style desired, the airflow may or may not be heated. A concentrator is a known attachment which focuses and flattens the emitted airflow, allowing the airflow to be directed to a specific area of the user’s hair. Certain hair types, such as textured hair, benefit from arranging the user’s hair with a comb or pic during the drying process, in order to avoid tangling of hair tresses. It is desirable to provide an attachment suitable for improving the ease and speed with which textured hair may be dried or styled.

SUMMARY OF THE INVENTION

In a first aspect, the present invention provides an attachment for a hair styling apparatus, the attachment comprising an air inlet for receiving airflow from the hair styling apparatus, an elongate slot-shaped air outlet, a duct for conveying air from the air inlet to the air outlet, a bar mounted within the duct and along the length of the air outlet and a series of comb teeth mounted on the bar.

The attachment may be especially beneficial for users with textured hair and the attachment may also be referred to as a pic or textured hair comb.

Preferably, the bar is adapted to flex torsionally. Further, the bar is preferably adapted to flex in a plane orthogonal to the length of the air outlet. It is preferred that each tooth in the series of comb teeth has a first end positioned within the duct and a second end disposed beyond the air outlet in a downstream direction, and the bar is adapted to enable each tooth to describe a spherical sector about an axis of the first end of the tooth.

Advantageously, the second end of each tooth may move, in use, to describe a circle of approximately 5 mm radius, and the second end of each tooth gently conforms to the shape of the user’s head, and resiliently returns to an aligned arrangement when not in use.

In a preferred embodiment, the bar comprises a securing means at each end for mounting the bar within the duct. Preferably, the securing means provides a fixed join or a pivoted join. It is preferred that the bar is formed of a flexible material, such as a nylon material.

In a preferred embodiment, the bar and the series of comb teeth are formed as a single entity.

In a second aspect, the present invention provides an attachment for a hair styling apparatus, the attachment comprising an air inlet for receiving airflow from the hair styling apparatus, an elongate slot-shaped air outlet, a duct for conveying air from the air inlet to the air outlet, a series of comb teeth mounted across the air outlet, each tooth having a first end located substantially at the air outlet and a second end disposed beyond the air outlet in a downstream direction, wherein at least one tooth comprises a planar, triangular form, oriented substantially orthogonally to the length of the air outlet.

Advantageously, the attachment functions as a drying and detangling tool and the emitted airflow experienced by the user is generally uniform in temperature and velocity. The attachment improves the ease and speed with which textured hair may be dried or styled.

Preferably, the first end of the at least one tooth has a semi-circular profile. It is also preferred that the second end of the at least one tooth forms an apex. The apex may comprise a rod form and may further comprise a spherical form at a terminal end of the tooth. Preferably, each tooth has a width in the range of 0.5mm to 2mm. In a preferred embodiment, each tooth in the series of comb teeth is regularly spaced. Further, it is preferred that each tooth in the series of comb teeth is spaced from adjacent teeth by a distance in the range of 2mm to 8mm.

The first end of the outermost teeth in the series of comb teeth may be angled towards a longitudinal axis of the attachment. Further, the second end of the outermost teeth in the series of comb teeth may be angled towards a longitudinal axis of the attachment. Preferably, the series of comb teeth is formed of a flexing material.

Preferably, the attachment further comprises a series of vanes within the duct oriented substantially orthogonally to the length of the air outlet, and a downstream end of at least one vane of the series of vanes comprises an inverted semi-circular profile adapted to fit around the first end of an aligned tooth. It is also preferred that the first end of the aligned tooth is freely moveable within the inverted semi-circular profile of the at least one vane.

Advantageously, each tooth within the series of teeth has a limited range of movement, thereby enabling the series of teeth to conform to the shape of the user’s scalp, in use.

In a third aspect, the present invention provides an attachment for a hair dryer, wherein the hair dryer comprises a body having an outer wall, an inner bore and a duct therebetween, and an airflow outlet at a front face of the body; the attachment comprising an air inlet for receiving airflow from the hair dryer, an air outlet, a duct for conveying air from the air inlet to the air outlet, and a stabilizing member for positioning within the inner bore of the hair dryer.

Preferably, the air inlet is located between the stabilizing member and the duct of the attachment. Further, the stabilizing member is preferably generally cylindrical. It is preferred that the stabilizing member has a diameter in the range from 25mm to 50mm, and more preferably in the range from 32mm to 38mm.

In a preferred embodiment, the stabilizing member has a first end distal to the air inlet and a second end proximal to the air inlet, and the second end has a diameter in the range from 35mm to 37mm. Preferably, the stabilizing member tapers from the second end to the first end. It is preferred that the stabilizing member has a friction fit with the inner bore of the hair dryer.

The diameter of the cylindrical stabilizing member may increase gradually from the first end to the second end in order to achieve a flush fit between the stabilizing member and the inner bore of the hair dryer along the length of the stabilizing member.

The attachment may comprise a seal disposed between the stabilizing member and the inner bore of the hair dryer, and said seal may be an elastic o-ring attached to the stabilizing member.

Preferably, the air inlet is a slot, and further, may be an annular slot. The attachment preferably comprises a ring of magnet material adjacent to and extending around the air inlet. Furthermore, the length of the stabilizing member is preferably in the range from lOmm to l20mm.

Airflow emitted from the air outlet of the hairdryer may have a temperature range up to around l30°C.

In a fourth aspect, the present invention provides an attachment for a hair styling apparatus, the attachment comprising an air inlet for receiving airflow from the hair styling apparatus, an elongate slot-shaped air outlet, a duct for conveying air from the air inlet to the air outlet, an airflow guiding entity located at least partially within the duct, said airflow guiding entity having a plurality of vanes orientated substantially orthogonally to the length of the air outlet, and a series of comb teeth mounted across the air outlet, each tooth having a first end located at the air outlet and a second end disposed beyond the air outlet in a downstream direction.

Preferably, at least one of the vanes substantially abuts a first end of a tooth. Further, it is preferred that each vane comprises a downstream terminal edge having an inverted semi-circular form.

In a preferred embodiment, the airflow guiding entity is a bung comprising a substantially circular first end and a domed second end. It is also preferred that the vanes are connected to an outer surface of the bung and extend from the circular first end to the domed second end and protrude beyond the second end. The air inlet may comprises at least one slot, and more preferably, the air inlet comprises an annular slot located around the first end of the bung.

In a further preferred embodiment, the air inlet is located at one end of the duct, and the air outlet extends along the length of the duct. The airflow guiding entity may be a series of vanes, each spanning the duct in proximity to the air outlet. Advantage is found in utilizing one or more vanes within the duct in order to direct the inlet airflow smoothly, through approximately 90 degrees, towards the air outlet. Preferably, the cross-sectional area of the duct decreases in size from the air inlet along the length of the air outlet. Further, the attachment preferably comprises a contoured duct wall extending between the air inlet and the air outlet.

Advantageously, turbulent airflow is minimized within the attachment and consequently the audible volume of the hot air styling device with attachment is minimized in use.

Features described above in connection with the first aspect of the invention are equally applicable to the further aspects of the invention, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:

Figure l is a front perspective view of an attachment;

Figure 2 is a top view of the attachment;

Figure 3 is a side view of the attachment;

Figure 4 is a front view of the attachment;

Figure 5 is a rear view of the attachment;

Figure 6 is a front perspective view of a hair-engaging section of the attachment;

Figure 7 is a front perspective view of a bung of the attachment;

Figure 8 is a front perspective view of a sleeve of the attachment;

Figure 9 is a front perspective view of a securing member of the attachment;

Figure 10 is a top view of the bung and the hair-engaging section of the attachment;

Figure 11 is a side view of the bung and the hair-engaging section of the attachment;

Figures l2a, l2b, l2c and l2d show a top view, a side view, a front view and a rear view respectively, of the hair-engaging section of the attachment;

Figure l3a is a schematic diagram of a horizontal cross-section through a further embodiment of the attachment, also illustrating airflow; Figure l3b is a schematic diagram of a horizontal cross-section through the attachment, also illustrating airflow;

Figure 14 is a front perspective view of the attachment with a protective cap;

Figure 15 is a front view of the attachment with the protective cap;

Figure 16 is a front perspective view of an example of a hair dryer to which the attachment may be connected;

Figure 17 is a side view of an alternative attachment;

Figure 18 is a cross-sectional view of a further embodiment of the alternative attachment;

Figure 19 is an end view of the attachment shown in Figure 18;

Figure 20 is a top view of a yet further embodiment of the alternative attachment;

Figure 21 is a side view of an example of a hot air styler to which the alternative attachment may be connected.

DETAILED DESCRIPTION OF THE INVENTION

Figures 1 to 5 are external views of an attachment 10. The attachment 10 comprises an air inlet 12 for receiving airflow from an air outlet end of a hair dryer or similar apparatus. The air inlet 12 is an annular aperture defined by an annular magnet 14 at the outer periphery and a circular end of a central bung 16 at the inner periphery. A sleeve 18 is located downstream of the air inlet 12 and covers the bung 16. A series of elongate teeth 20 protrude from the downstream opening 22 of the sleeve 18. A stabilizing cylindrical member 24 extends about a longitudinal axis, x, of the attachment 10 at the upstream side of the air inlet 12. The distal end of the cylindrical member 24 comprises an elastic O-ring 26.

Figure 6 illustrates the hair-engaging section 28 of the attachment which comprises the series of elongate teeth 20 connected to a bar 30 extending along an axis, y, transverse to the longitudinal axis of the attachment 10. Each tooth 20 has a triangular blade form, orientated with a blade edge 32 aligned with the longitudinal axis, x, of the attachment 10. A wide, first end 34 of each tooth has a rounded profile. The bar 30 is flexible and allows movement of the connected teeth in several orientations. A lug 36 is positioned at the first end of the outside tooth 20 at each side of the hair-engaging section 28, and an aperture 40 is located within each lug 36.

Figure 7 illustrates the bung 16 which has a generally conical form with a series of vanes 42 located on the outer surface of the bung 16. A first end of the bung 16 is a generally circular opening 44 or wall and a second end is a rounded dome form. Seven vanes 42 are illustrated and each vane within the series of vanes is generally aligned with the longitudinal axis, x, of the attachment. At the first end of the bung 16, the vanes 42 commence on both opposing sides of the circular opening 44, extend over the tapering surface of the bung 16, and then meet at the second end of the bung. In the embodiment illustrated, the vanes terminate in a c-shaped profile 46.

A flange 48 is located at the first end of the bung which cooperates with the second end 50 of the cylindrical member 24. A pair of snap-fit arms 52 are located towards the first end of the bung on opposing sides of the circular opening 44, on the transverse plane, y, of the attachment 10. These snap-fit arms 52 engage with an annular magnet 14 which is illustrated in Figures 2 and 3. The annular magnet 14 has an annular plastics casing 15 which partially surrounds an outer surface of the magnet 14.

The sleeve 18 is an annulus having a rounded rectangular cross-section, which is adapted at a first end to accommodate the bung 16. The first end 22 of the sleeve 18 also comprises an end wall 54 extending transverse to the longitudinal axis of the attachment 10 and defining a shoulder 56 of the sleeve 18. There may be a discontinuity between the side wall of the sleeve 18 and the end wall 54, forming a port 53 through which ambient air may transfer.

As shown in Figure 8, a pair of apertures 58 are located on opposing sides of the second end of the sleeve 18, on the transverse plane, y, of the attachment 10. Several locating protrusions 60, 62 are positioned on an inner surface of the sleeve 18.

The cylindrical member 24 has four walls 64 located radially within the cylinder, extending from an axial fixing member 66 to an inner surface 68 of the cylinder. As shown in Figure 9, an inner surface 68 of a first end of the cylindrical member 24 is adapted to engage with an outer surface of the flange 48 of the bung 16.

Figure 10 shows the arrangement of the bung 16 and the hair-engaging section 28, and in particular, the alignment of the vanes 42 with the teeth 20. In the embodiment illustrated, the seven vanes 42 of the bung 16 align with the seven central teeth 20 of the hair-engaging section 28. The first end 34 of at least three further teeth 20 at each side are inclined towards the longitudinal axis of the attachment, x. The c-shaped profile of the second end of the vanes 42 cooperates with the semi-circular first end of the seven central teeth 20, as shown most clearly in Figure 11.

The hair-engaging member 28 comprises a plurality of teeth 20 connected to a bar 30. In the embodiment illustrated in Figure l2a, the bar 30 is generally rectangular in cross- section. The hair-engaging member 28 may be molded as a single element, or individual teeth 20 may be fixed onto a bar 30. Two alternative tooth profiles are illustrated in Figure l2b. The left-hand side profile has straight blade edges which join at a curved tip 76. In the right-hand side profile, a rod 78 extends from a narrow, second end of each tooth and the terminal end of the rod comprises a ball-form 80. With reference to Figures l2a and l2b, the depth, d, of each tooth is in the range from 5mm to 25mm, and in this embodiment is in the range from l6mm to l8mm. The length, 1, of each tooth external to the air outlet is in the range from 30mm to 80mm, and in this embodiment is in the range from 50mm to 60mm. The width, w, of each tooth is in the range from 0.5mm to 2.5mm, and in this embodiment is in the range from l.7mm to l.9mm. The number of teeth in the hair-engaging member is in the range from 7 and 20, and in this embodiment is in the range from 12 to 14. The length of the flexing bar, b, is in the range from 50mm to 80mm, and in this embodiment is in the range from 60mm to 70mm.

During assembly of the components of the attachment 10, the sleeve 18 is moved to surround the junction between the hair-engaging member 28 and the bung 16. The lugs 36 at the first end of the hair engaging member 28 align with the apertures 58 in the second end of the sleeve 18. A pin 41 is inserted through each aperture 58 and into a receiving aperture 40 in each lug 36, respectively. The cylindrical stabilizing section 24 is connected to the bung 16 via the flange 48 at the first end of the bung 16. Optionally, a screw connection between the axial fixing member 66 of the cylindrical section and an axial protrusion (not shown) within the bung 16, may be used reinforce this connection. The annular magnet 14, which is preferably partly encased by plastic 15, is moved along the cylindrical section 24 towards the bung 16, and secured in position by the snap-fit arms 52.

With reference to Figure 8, the locating protrusions 60, 62 can be fused to the nearest vane 42 by, for example, ultrasonic welding. Such a fused structure also functions to add rigidity to the attachment 10.

In use, the textured hair pic 10 is attached to the airflow outlet end of a hair dryer 72. An example of a hair dryer to which the pic may be attached is illustrated in Figure 16. Such a hair dryer is described in W02015/001306, the contents of which are incorporated herein by reference, in which heated airflow is emitted from an annular slot located at the air outlet end of the hair dryer 72. The air outlet slot 84 extends around a bore 70 of the hair dryer. The cylindrical member 24 of the attachment 10 is inserted into the bore 70 of the hair dryer 72 in order to provide a stable arrangement between the attachment 10 and hairdryer 72. Further, the annular magnet 14 of the attachment 10 engages with a ring of magnetic material 86, which is adjacent to the air outlet slot 84 of the hair dryer 72. The elastic O-ring 26 provides further engagement between the outer surface of the attachment 10 and the inner surface of the bore 70 in the hair dryer 72. Even when significant force is exerted on the attachment 10 via the teeth 20, the cylindrical member 24 functions to avoid relative movement between the attachment 10 and the hairdryer 72.

Airflow emitted from the hair dryer 72 passes through the annular air inlet 12 of the attachment and passes over the surface of the bung 16, guided by the vanes 42, and bounded by the sleeve 18. The airflow continues past the first end of the hair-engaging section 28, and through the air outlet 22, as defined by the second end of the sleeve 18. Guided by the plurality of teeth, the airflow continues towards the second end of the hair-engaging section 28. As a heated air flow passes through the attachment 10, the temperature of the components will rise. To avoid contact with the warmest parts of the attachment, the user may position their fingers at the short sides of the sleeve 18. Further, the sleeve may comprise a double wall with a gap between, thereby creating an insulating effect.

The user may move the attachment 10 through their hair, and the teeth 20 may be in contact with the user’s scalp. The flexing bar 30 allows the teeth 20 to move and thereby conform to the shape of the user’s head. Further, each tooth 20 is comprised of a flexing material. The user’s movement of the attachment 10 through the hair may be irregular and the arrangement of the hair may be non-uniform, and thus individual teeth may be urged in different directions or rotations. The flexing bar 30 enables such movement of the teeth 20 to a limited extent. The greatest movement of the teeth 20 occurs at the terminal end of each tooth. When movement of a terminal end of a tooth is in alignment with the z-axis, as shown in Figure 6, said tooth can be considered to “pivot” about the flexing bar 30, although the junction of the bar and each tooth remains in a fixed relationship. Consequently, the first end of each tooth has limited rotational movement. Advantageously, the c-shaped second end 46 of the vanes 42 allows such rotational movement of the respective tooth without obstruction. Movement of the second end of a tooth 20 in alignment with the y-axis, may cause limited movement of the first end of the tooth in the same axis. Again, such movement is not obstructed by the vanes 42.

Each of the components of the attachment 10 is formed from a plastics material. In particular, the hair-engaging member comprises glass filled nylon or super-tough nylon.

Figures l3a and l3b illustrate the advantageous effect of the vanes 42 on the outer surface of the bung 16. The airflow pattern is shown as a shaded area. Figure l3a schematically shows an attachment in which the vanes are absent. The airflow passes from the air inlet to the air outlet, generally undeflected, and negligible flow is present at the outermost sides of the hair-engaging member. In contrast, Figure l3b schematically shows an attachment with vanes and thus the airflow is deflected by the vanes and the cross-section of the airflow at the outlet is greater than the airflow at the inlet. Specifically, the vanes 42 on the bung 16 guide the airflow from the inlet to expand across the complete width of the air outlet 22. Therefore, airflow is directed through a greater area of the user’ s hair, and consequently the time required to dry hair is reduced.

A protective cap 82 can be positioned over the hair-engaging portion 28 when the attachment 10 is not in use. The protective cap 82, illustrated in Figure 14, comprises a sleeve 85 having a similar transverse cross-sectional form and dimensions to the sleeve 18 of the attachment. One major side is cut away, and a first end has walls 87 adapted to receive the first end of the teeth 20 and a second end has a pair of transverse walls 88 adapted to receive the second end of the teeth.

When the attachment 10 has been in use with a high temperature airflow and significant stresses inflicted on the teeth 20, it is possible that the teeth may deform as a consequence of the properties of the plastics material from which the teeth are comprised. After use, the protective cap 82 can be slid over the hair-engaging section 28, in the direction of the arrow in Figure 14, until the first end of the protective cap 82 abuts the second end of the sleeve 18. In this way, the teeth 20 are retained in the correct position as the temperature of the attachment falls and returns to the ambient temperature. The cut-away section 90 of the protective cap improves the rate of thermal transfer from the teeth as the temperature of the attachment 10 falls. Additionally, the protective cap 82 functions to protect the teeth from some impacts and possible damage when the attachment 10 is not in use.

An alternative pic attachment, for use with a hot air styling device, is shown in Figures 17 to 20. The attachment 100 comprises an air inlet 102, defined by a collar 104, for receiving an airflow from an air outlet end of a hot air styling device. The air inlet 102 is generally circular in shape, to enable an air-tight connection with a generally circular air outlet end of the hot air styling device. Regularly spaced protrusions 106 on the collar 104 enable a click-fit connection to the air outlet end of the hot air styling device. Alternative connection options will be apparent to the skilled person, such as screw-fit or push-fit arrangements.

The air inlet 102 is in fluid communication with a duct 108. The duct 108 has an air outlet 110 which is elongate in shape. An external surface of the attachment 100 is in the form of a sleeve 112 extending partially about the duct 108. The air outlet 110 may extend beyond the top opening of the sleeve 112.

Whilst the embodiment illustrated in Figure 17 comprises 13 teeth in the hair-engaging section, Figure 18 shows a further embodiment comprising 15 teeth in the hair-engaging section. Figure 20 shows a yet further embodiment comprising 17 teeth in the hair- engaging section.

Figure 18 is a cross-sectional view which shows a gradually reducing depth of the duct 108 towards a distal end of the attachment 100. Consequently, the cross-sectional area of the duct 108 decreases, or tapers, gradually towards the distal end of the attachment 100. The cross-sectional area of the sleeve 112 does not vary in size along its length towards the distal end of the attachment 100, and so the spacing between the duct 108 and the sleeve 112 gradually increases in cross-sectional area towards the distal end of the attachment, forming a chamber 114. At the upstream end of the duct 108, a contoured wall 116 extends between the air inlet 102 and air outlet 110.

The embodiment illustrated in Figure 18 shows an attachment comprising five vanes 118, 120, 122, 124, 126. The unbroken vane 118 is in closest proximity to the airflow inlet end of the duct 108 and has an aerofoil form. The orientation of the unbroken vane 118 is aligned closely to the natural airflow direction, and a downstream end of vane 118 terminates normal to the air outlet 110.

The four further vanes 120, 122, 124, 126 are split vanes, each comprising a major section and a minor section. Each vane has slightly differing dimensions and proportions. A downstream end of the major section of each split vane is a narrow tail which terminates normal to, and in close proximity to, the air outlet. The downstream ends of the major section of each split vane are positioned at approximately regular intervals of 14mm- 15 mm.

With reference to Figure 18, the upstream end of each vane (or minor vane) 118, 120, 122, 124, 126 is in alignment with the direction of the incident primary airflow (indicated by an arrow) entering the attachment 100 through the primary air inlet 102. The downstream end of each vane (or major vane) 118, 120, 122, 124, 126 is in alignment with the direction of the emitted airflow exiting the attachment through the airflow outlet 110. Alternatively, each vane in the alternative attachment 100 may comprise a single, curved vane instead of a major section and a minor section.

A hair-engaging section 128, similar to the hair-engaging section previously described and as illustrated in Figures 6 and l2a, is located at the air outlet 110 of the attachment 100. Lugs 130 at each end of the hair-engaging section 128 are attached to the duct walls 132 at the short ends of the elongate air outlet 110. A pin 134 passes through an aperture in the duct walls 132 and into a receiving aperture in each lug 130. A flexing bar 136 extends across the air outlet 110, to which a plurality of teeth 138 are attached. A first end 140 of some of the plurality of teeth 138 abut the downstream ends of the vanes 118, 120, 122, 124, 126. The vanes have a c-shaped downstream end and the teeth 138 have a semi-circular upstream end and so limited movement of the teeth is enabled, as described with respect to the hair engaging member and vanes of the attachment illustrated in Figures 1 to 15.

In use, the attachment illustrated in Figures 17 to 20 is attached to the airflow outlet end of a hot air hair styling device. The airflow passes through the air inlet 102 of the attachment to enter the duct 108. The airflow is guided by the vanes 118, 120, 122, 124, 126 towards the air outlet 110 where the airflow is emitted from the attachment 100.

At the upstream end of the duct 108, the contoured wall 116 functions to direct the airflow towards the air outlet with a minimum of turbulence and low velocity flow. The airflow velocity of the airflow proximal to the airflow inlet is adequate to ensure a required level of attachment of the airflow to the unbroken vane. Split vanes function to improve attachment of the airflow to the vane as the incident airflow velocity is reduced. The airflow exiting the outlet 110 is straight, even flow with an outlet airflow velocity lower than the inlet airflow velocity. Furthermore, the outlet airflow has a relatively slow velocity decay and leaves the duct 108 uniformly at right-angles to the direction of the incident airflow into the attachment 100. In an exemplary embodiment, the velocity of the airflow exiting the duct is around 30m/s - 35m/s. The outlet airflow is guided by the teeth, thereby continuing the emitted straight, even flow towards the user’s hair. In use, the movement of the teeth 138 in this alternative attachment is similar to the movement of the teeth in the hairdryer attachment, as described previously.

The cross-sectional area of the duct 108 tapers gradually towards the distal end of the attachment 100. The function of this reduction in cross-sectional area is to ensure a constant pressure of airflow exiting the attachment along the entire length of the air outlet and to prevent turbulent flow. Specifically, the reduction in cross-sectional area is proportional to falling mass flow rate of the airflow within the duct. The mass flow falls as airflow exits the duct via the air outlet from the upstream end of the attachment to the downstream end of the attachment. Consequently, the reduction in cross-sectional area of the duct 108 results in a constant outlet airflow velocity along the length of the air outlet. It is also observed that attachment of airflow to vanes 118, 120, 122, 124, 126 is improved as a consequence of the reduction in cross-sectional area of the duct. Also, a balanced distribution of airflow is achieved at the air outlet.

The inlet airflow may be heated before entering the attachment 100 and consequently the duct may become hot during use. The sleeve 112 functions as a cool wall to minimize the temperature of the outermost surface of the attachment, as the air-filled chamber 114 insulates the sleeve from the duct.

A protective cap, as illustrated in Figure 14, can also be used with the further embodiment illustrated in Figures 17 to 20.

With reference to the embodiment illustrated in Figure 19, the second end 140 of each tooth 138 may omit the rod and ball, having only an apex of the triangular blade form. Advantageously, a tooth having a plain apex at the second end 140 is less prone to breakage or deformity, in use. The flexing bar 136 may have any suitable form, such as a circular or oval cross-section.

In a further embodiment of the alternative attachment 100, as shown in Figure 20, the sleeve 112 may be inclined towards the duct at the airflow outlet. This functions to enable outlet airflow (which may be referred to as“primary airflow”) to entrain air present in the chamber 114, thereby moving air through the chamber and drawing ambient air in through the port 142 between the sleeve 112 and the duct 108. Ambient air moving through the chamber (which may be referred to as“secondary airflow”) enhances the efficacy of the cool wall effect of the sleeve 112. However, the secondary airflow is cooler than the heated primary airflow and therefore relative proportions of the secondary and primary airflow should be controlled in order to optimise the airflow temperature experienced by the user. Such control is realized by an airflow outlet geometry, which is comprised of the dimensions and relative location of the primary airflow outlet and the secondary airflow outlet.

In a preferred embodiment, the depth, d, (shown in Figure 18) of the further attachment is in the range from 30mm to 70mm, and in this embodiment is in the range from 40mm to 60mm. The height, c, of the attachment from the top of the sleeve to the air inlet is in the range from 80mm to l20mm, and in this embodiment is in the range from 90mm to l lOmm.

Figure 21 shows an example of a hot air styling device 144 to which the further attachment 100 may be connected. The hot air styling device 144 comprises a generally tubular handle 146 having an air inlet 148 and an air outlet 150 at opposing ends. At the air inlet 148, an array of apertures 152 extend around and partially along the handle 146. A fan unit (not shown) is housed within the handle and comprises a fan and a motor. In use, the motor drives the fan and air is drawn in through the air inlet, along an air flow path which extends through the length of the handle. The air is optionally heated by a heater (not shown) before exiting the hot air styling device 144 at the air outlet 150.

The attachments 10, 100 may be fabricated from any suitable heat resistant material, and in a preferred embodiment, are fabricated from glass-filled nylon. The highest preferred operating temperature of such attachments connected to a hot air styling device or hairdryer is approximately 130 degrees centigrade.

The complete attachments are secured together at multiple points within each attachment using one or more of glue, screws, ultrasonic welding and push-fit fixings. In an alternative embodiment, a tooth may comprise one or more apertures, curved edges, or a non-uniform blade width. Further, the series of teeth may comprise more than one tooth design. In an alternative embodiment, it may be desirable to produce a reduced exit airflow velocity from an attachment whilst utilizing a similar hot air styling device or hairdryer to provide the input airflow. This may be achieved by increasing the overall dimensions of the attachments. It will also be apparent to the skilled person that utility is found in the attachments alone. Specifically, the attachments described herein may be used without airflow and a user would benefit significantly from the flexing bar and consequently mobile teeth.

The invention is not limited to the detailed description given above. Variations will be apparent to the person skilled in the art.

Claims

1. An attachment for a hair styling apparatus, the attachment comprising:

an air inlet for receiving airflow from the hair styling apparatus; an elongate slot-shaped air outlet;

a duct for conveying air from the air inlet to the air outlet;

a bar mounted within the duct and along the length of the air outlet; and a series of comb teeth mounted on the bar, wherein the bar is adapted to flex torsionally.

2. An attachment according to claim 1, wherein the bar is adapted to flex in a plane orthogonal to the length of the air outlet.

3. An attachment according to any preceding claim, wherein each tooth in the series of comb teeth has a first end positioned within the duct and a second end disposed beyond the air outlet in a downstream direction, and the bar is adapted to enable each tooth to describe a spherical sector about an axis of the first end of the tooth.

4. An attachment according to any preceding claim, wherein the bar comprises a securing means at each end for mounting the bar within the duct.

5. An attachment according to claim 4, wherein the securing means provides a fixed join.

6. An attachment according to claim 4, wherein the securing means provides a pivoted join.

7. An attachment according to any preceding claim, wherein the bar is formed of a flexible material.

8. An attachment according to claim 7, wherein the bar is formed of a nylon material.

9. An attachment according to any preceding claim wherein the bar and the series of comb teeth are formed as a single entity.