GB2548616A

GB2548616A - An attachment for a hand held appliance

Info

Publication number: GB2548616A
Application number: GB1605018.9A
Authority: GB
Inventors: James Harvey Heffer Jonathan; Anthony Mason Richard; Victoria Carson Emma; Rita Nicolson Annmarie
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2016-03-24
Filing date: 2016-03-24
Publication date: 2017-09-27
Anticipated expiration: 2036-03-24
Also published as: WO2017163003A1; CN207023591U; CN107224080A; EP3432756A1; US20170273422A1; GB2548616B; GB201605018D0; KR20180121607A; AU2017236454A1; JP6518281B2; CN115804494A; AU2017236454B2; JP2017170147A; RU2694927C1

Abstract

An attachment for a hair care appliance comprising at least one vane 100 for directing fluid within a flow path towards an outlet 50 wherein the body 12 of the attachment comprises at least two extended plates 40 and the outlet comprises a slot defined by an overlap between the plates; and wherein the at least one vane is positioned within the overlap between the at least two extended plates. The body may be elongate and may have a first end 14 including the fluid inlet and a second end 16 and may extend along an axis. The fluid outlet may extend along the axis between the first end and the second end. The at least one vane may change the direction of fluid flow. The attachment could be an attachment for a hairdryer or other hot air styling device and is suitable for curling the hair.

Description

AN ATTACHMENT FOR A HAND HELD APPLIANCE FIELD OF THE INVENTION

This invention relates to an attachment for a hand held appliance, in particular a hair care appliance such as a hot styling appliance.

BACKGROUND OF THE INVENTION

In a conventional hot styling device, air is drawn into an inlet by a fan unit and directed towards the hair by a head or attachment. Depending on the style desired, the air may or may not be heated. The head or attachment often includes bristles onto which hair is wrapped and held for styling. The air is generally blown out of the attachment normal to the surface of the attachment. When styling hair in curls it can be difficult to unwrap the hair from the bristles and the hair may become tangled.

When styling hair in curls it is also known to use curling tongs in which a heated barrel may reach high temperatures before the hair is wrapped around the barrel and then secured by a barrel clip for a period of time. Repeated use of such curling tongs at high temperatures may damage the hair.

SUMMARY OF THE INVENTION A first aspect of the invention provides a hair care appliance comprising a body having a fluid inlet, a fluid outlet, a fluid flow path extending between the fluid inlet and the fluid outlet and at least one vane for directing fluid within the fluid flow path towards the fluid outlet wherein the body comprises at least two extended plates and the fluid outlet comprises a slot defined by an overlap between the at least two extended plates and wherein the at least one vane is positioned within the overlap between the at least two extended plates.

Advantage is found in providing vanes on the inner face of each plate which function to guide the flow precisely as it exits the attachment. Specifically, a uniform airflow exiting the attachment will allow hair strands to attach uniformly over the length of the barrel.

Preferably, the body is elongate and extends along an axis. In a preferred embodiment, the elongate body has a first end and a second end and the fluid inlet is at the first end. Preferably, the fluid outlet extends along the axis between the first end and the second end.

In a preferred embodiment, the at least one vane is an aerofoil. This shape is advantageous as it reduces turbulence.

Preferably, the at least one vane directs fluid flowing in the fluid flow path from a first direction to a second direction. In a preferred embodiment, the first direction is parallel to the axis of the body. Preferably, the second direction is 85° to 95° from the axis.

In a preferred embodiment, the at least one vane comprises a plurality of vanes extending from the first end of the body towards the second end of the body.

Preferably, the plurality of vanes are irregularly spaced along the body. In a preferred embodiment, the plurality of vanes are progressively closer together towards the second end.

Preferably, the plurality of vanes are angled to the axis of the body. In a preferred embodiment, the angle of at least some of the plurality of vanes differs from adjacent vanes. Preferably, the angle of the plurality of vanes with respect to the axis increases towards the second end.

Advantage is found in providing vanes of varying angles within the overlap, wherein the angles of the vanes are dependent upon the position of the vane along the length of the attachment in order to optimize airflow attachment.

In a preferred embodiment, the size of the plurality of vanes varies between the first end and the second end. Preferably, the plurality of vanes are progressively smaller towards the second end of the body.

In a preferred embodiment, each of the plurality of vanes has the same profile.

Preferably, the slot is curved with respect to the axis of the body. Advantage is found in combining a twisting helical form of each plate which provides helical fluid outlet slots and internal vanes to direct the flow out of an attachment as this enhances attachment of the airflow to the surface of the attachment.

In a preferred embodiment, the at least one vane is substantially the same length as the overlap between the at least two extended plates.

Preferably, one of the at least one vanes has a structural function as well as a flow directing function.

In a preferred embodiment, each extended plate is formed from a strut and a plate.

Preferably, the slot is formed from a strut and a plate from adjacent extended plates.

According to a second aspect, the invention provides an attachment for a hair care appliance comprising an elongate body having a first end and a second end, a fluid inlet at the first end, a fluid outlet and a fluid flow path extending between the fluid inlet and the fluid outlet wherein a cool tip is provided adjacent the second end of the elongate body and the cool tip is spaced from the second end of the elongate body. A gap between the underside of the cool tip and the adjacent end of the elongate body advantageously minimizes transfer of heat to the cool tip and also has the advantage of allowing for manufacturing tolerances between the assembly sub-sections.

Preferably, an air gap is provided between the cool tip and the second end of the elongate body.

In a preferred embodiment, the cool tip comprises an annular flange which extends around the second end of the elongate body. Preferably, the elongate body has an outer wall. In a preferred embodiment, the annular flange is spaced from the outer wall.

In a preferred embodiment, the cool tip comprises a handle extending from the flange. Preferably, the handle is cylindrical. In a preferred embodiment, the handle is hollow. Having a hollow handle on the cool tip is advantageous as air within provides further insulation.

Preferably, the outer wall is formed from at least two plates that extend from the first end to the second end.

In a preferred embodiment, the fluid outlet comprises a slot wherein the slot extends between the at least two plates. Preferably, the slot is curved. In a preferred embodiment, the fluid outlet comprises more than one slot.

According to a third aspect, the invention provides an attachment for a hair care appliance comprising a first subassembly and a second subassembly wherein the first subassembly comprises a cage onto which components of the second subassembly are mounted.

Preferably, the first subassembly is formed from a plurality of spaced apart struts.

In a preferred embodiment, the second subassembly comprises a plurality of plates.

Preferably, each of the plurality of spaced apart struts comprises a longitudinal flange extending from the first end to the second end. In a preferred embodiment, each of the plurality of plates comprises a cooperating longitudinal flange.

Preferably, an equal number of plates and struts are provided.

In a preferred embodiment, the first subassembly comprises at least one structural vane extending between a pair of adjacent struts.

Preferably, the second subassembly comprises a plurality of plates and each of the plurality of plates comprises an indentation for accommodating the at least one structural vane.

In a preferred embodiment, the attachment comprises an elongate body formed from the plurality of spaced apart struts and the plurality of plates. Preferably, the elongate body comprises a first end and a second end.

In a preferred embodiment, each of the plurality of plates and plurality of spaced apart struts are provided with one of a cooperating pair of protrusions and recesses at the first end of the elongate body. Preferably, each of the plurality of plates and plurality of spaced apart struts are provided with a second one of a cooperating pair of protrusions and recesses at the second end of the elongate body.

In a preferred embodiment, following attachment of the plurality of plates to the first subassembly, the plurality of plates are welded to the first subassembly.

Preferably, each of the plurality of spaced apart struts comprises a longitudinal flange extending from the first end to the second end and each of the plurality of plates comprises a cooperating longitudinal flange and these flanges are welded together.

In a preferred embodiment, at the distal end of each of the plurality of spaced apart struts and each of the plurality of plates from the longitudinal flange and cooperating longitudinal flange is a slot and this slot forms part of a fluid outlet from the attachment.

Preferably, a plurality of vanes are provided within the slot. In a preferred embodiment, the plurality of vanes serve to maintain a slot gap between the strut and plate.

Preferably, the plurality of vanes serve to turn fluid flowing out of the slot.

In a preferred embodiment, at the first end of the elongate body, a connection ring is provided for connecting the attachment to a hair care appliance.

In a fourth aspect, the invention provides an attachment for a hair care appliance comprising an elongate body having a first end and a second end, an fluid inlet at the first end, an fluid outlet and a fluid flow path extending between the fluid inlet and the fluid outlet wherein a collar is proved at the first end and the collar extends around the elongate body.

Advantage is found in providing a squared ledge or collar at the first end of the attachment which functions to avoid entrainment of air near the hot air styling device and to avoid hair wrapping down the hot air styling device.

Preferably, the fluid outlet extends from adjacent the collar towards the second end of the elongate body. In a preferred embodiment, the collar extends out from the elongate body. Preferably, the elongate body extends along an axis and the collar is substantially orthogonal to the axis of the elongate body. In a preferred embodiment, the elongate body extends radially out from the axis and the collar extends further from the axis than the elongate body. Preferably, the collar extends radially around the elongate body.

In a preferred embodiment, the fluid outlet comprises at least one slot extending along the elongate body.

Preferably, the outer wall is formed from at least two extended plates and the at least one slot extends between the at least two extended plates.

In a preferred embodiment, the elongate body extends along an axis and the at least one slot is curved with respect to the axis. Preferably, the at least one slot is helical.

According to a fifth aspect, the invention provides an attachment for a hair care appliance comprising an elongate body having a first end and a second end, a fluid inlet at the first end, a fluid outlet and a fluid flow path extending between the fluid inlet and the fluid outlet wherein the diameter at the first end is larger than the diameter at the second end and the fluid outlet extends from the first end to the second end.

Preferably, the elongate body converges from the first end towards the second end.

In a preferred embodiment, the elongate body gradually reduces in diameter from the first end. Preferably, the reduction in diameter extends along a portion of the elongate body. In a preferred embodiment, there is a gradual transition from the diameter at the first end to the diameter at the second end.

Preferably, the elongate body comprises an extended plate extending from the first end to the second end. In a preferred embodiment, the extended plate has a thickness and the thickness of the plate is substantially uniform along the body.

Preferably, any change in diameter along the length of the elongate body is both an internal change and an external change.

In a preferred embodiment, the elongate body flares towards the first end. Advantageously, a flared profile of a first end of the attachment reduces turbulence and thereby aids initial attachment of the end of a hair strand. Further, hair is wrapped from a second end of the attachment towards the airflow inlet end.

Preferably, the elongate body extends along an axis and has a substantially constant diameter along the axis from the second end towards the first end.

In a preferred embodiment, the fluid outlet comprises at least one slot extending along the elongate body. Preferably, the elongate body extends along an axis and the at least one slot is curved with respect to the axis. In a preferred embodiment, the at least one slot is helical.

Advantageously, the attachment of the present invention may be provided in different sizes to enable several sizes of curls to be styled. Furthermore, either clockwise helical airflow outlet slots or anti-clockwise helical airflow outlet slots can be utilised. The direction of overlap of a slot determines the direction of curl.

According to a sixth aspect, the invention provides an attachment for a hair care appliance comprising a body having a fluid inlet, a fluid outlet, a fluid flow path extending between the fluid inlet and the fluid outlet, a first vane and a second vane for directing fluid within the fluid flow path towards the fluid outlet wherein the body comprises at least two extended plates and the fluid outlet comprises a slot defined by an overlap between the at least two extended plates wherein the first vane and the second vane are curved and positioned within the overlap between the at least two extended plates wherein the first vane and the second vanes curve in opposite directions.

Preferably, the fluid inlet comprises a first cross sectional area, the body comprises an outer wall and the outer wall of the body comprises a second cross sectional area wherein the second cross sectional area is greater than the first cross sectional area.

In a preferred embodiment, the fluid inlet has a diameter df and the attachment has a diameter d2 wherein d2 is greater than df.

Preferably, the body is elongate and extends along an axis. In a preferred embodiment, the body has a first end and a second end and the fluid inlet is at the first end.

Preferably, the first vane is adjacent the fluid inlet. In a preferred embodiment, the first vane has a convex surface and the convex surface faces the fluid inlet.

Preferably, the second vane has a concave surface and the concave surface faces the fluid inlet.

In a preferred embodiment, the first vane and the second vane are aerofoil in shape.

Preferably, the fluid outlet extends along an axis between the first end and the second end.

In a preferred embodiment, the second vane comprises a plurality of vanes spaced along the extended plates. Preferably, the plurality of vanes are irregularly spaced along the extended plates. In a preferred embodiment, the plurality of vanes are angled to the axis of the body. Preferably, the angle of at least some of the plurality of vanes differs from adjacent vanes. In a preferred embodiment, the angle of the plurality of vanes with respect to the axis increases towards the second end. Preferably, the size of the plurality of vanes varies along the extended plate. In a preferred embodiment, each of the plurality of vanes has the same profile. Preferably, the at least one vane is substantially the same length as the overlap between the at least two extended plates.

In a preferred embodiment, the slot is curved with respect to the axis of the body.

Preferably, each extended plate is formed from a strut and a plate.

In a preferred embodiment, the slot is formed from a strut and a plate from adjacent extending plates.

Preferably, the attachment further comprises at least one structural vane. In a preferred embodiment, the at least one structural vane connects between a strut and an adjacent strut. Preferably, the at least one structural vane connects between a strut and a plate.

Advantageously, a protrusion on a leading edge of an inner face of a plate provides enhanced airflow attachment to the outer surface of the attachment, in particular, in attachments of greater diameter (eg. 40mm).

According to a further aspect, the invention provides an attachment for a hair care appliance comprising a body having a fluid inlet, a fluid outlet and a fluid flow path extending between the fluid inlet and the fluid outlet wherein the fluid outlet comprises a slot defined by an overlap between a radially inner extended plate and a radially outer extended plate.

Preferably, the radially inner extended plate comprises a radially inner surface which curves radially inwards towards the overlap .

Preferably the radially inner extended plate comprises a strut and a plate.

In a preferred embodiment, the radially inner surface includes a reinforcing rib which preferably extends radially inwards of the strut. Preferably, this reinforcing rib is rounded so it provides a smooth transition for fluid flowing through the attachment.

The reinforcing rib extends from an inlet end of the overlap at least partial along the radially inner surface of the strut.

Preferably, the strut comprises a protuberance located adjacent an inlet end of the radially inner plate. This protuberance is a bulge or localised thickening of the strut. Preferably, the protuberance is substantially hemispherical. Preferably, the protuberance extends from an inlet end of the strut an outlet end of the strut. Alternatively, the protuberance extends partially along the strut.

In a preferred embodiment, the reinforcing rib, protuberance or bulge extends along substantially the whole length of the strut.

Preferably, adjacent the fluid inlet, the reinforcing rib, protuberance or bulge comprises a chamfer or angled face. This provides a smooth transition for fluid flowing into the attachment. Preferably, the attachment comprises a connection ring for connection to an appliance. In a preferred embodiment, the connection ring defines the fluid inlet into the attachment. Preferably, adjacent the connection ring, the reinforcing rib, protuberance or bulge lies in the same plane as the connection ring. In a preferred embodiment, the reinforcing rib, protuberance or bulge extends radially inwards to a minimum radius from the connection ring towards a downstream end of the attachment. Once the minimum radius is reached, it is preferred that the reinforcing rib, protuberance or bulge remains at a substantially constant radius from the longitudinal axis X-X of the attachment.

Preferably, the hair care appliance is a hot styling appliance.

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 1 is a perspective view of an embodiment of the present invention;

Figure 2a is an exploded view of the attachment;

Figure 2b is an isometric view of the first subassembly;

Figure 2c is an exploded view of the second subassembly;

Figure 3 is a side view of the attachment;

Figure 4 is a cross-sectional view taken along line A-A in Figure 3;

Figure 5 is a cross-sectional view taken along line B-B in Figure 3;

Figure 6 is a cross-sectional view taken along line X-X in Figure 3;

Figure 7 is a top end view of the attachment;

Figure 8 is a base end view of the attachment;

Figure 9 is a front view of a single plate;

Figure 10 is a side view of single plate;

Figure 11 is a perspective view of a second embodiment of the present invention;

Figure 12 is an exploded view of the attachment of Figure 11;

Figure 13 is a side view of the attachment of Figure 11;

Figure 14 is a cross-sectional view taken along line A-A in Figure 13;

Figure 5 is a cross-sectional view taken along line B-B in Figure 13;

Figure 16 is a longitudinal cross-sectional of the attachment of Figure 11;

Figure 17 is a side view of single plate of the attachment of Figure 11; and

Figure 18 is a side view of an example of a hot air styling device to which the attachment may be connected.

DETATT^D DESCRIPTION OF THE INVENTION

Figure 1 is an external view of an attachment 10 of the present invention. The attachment 10 comprises an fluid inlet 20 for receiving an airflow from an airflow outlet end of a hot air styling or similar device. The fluid inlet 20 is generally circular in shape, to enable an air-tight connection with a generally circular outlet end of the hot air styling device.

The attachment 10 is essentially cylindrical and extends longitudinally from the fluid inlet 20 to the distal end 30, preferably continuing a line described by the hot air styling device. The attachment has an elongate body 12 having a first end 14 and a second end 16. Elongate plates 40 extend from the first end 14 to the second end 16, and elongate slots 50 disposed between adjacent plates 40 comprise the fluid outlet for this attachment. The distal end 30 of the attachment 10 comprises a cool tip 32.

In this embodiment, the attachment 10 has a constant diameter di which extends at least partially along the elongate body 12 which is less than the diameter df of the fluid inlet 20.

Figures 2a, 2b, and 2c show exploded and isometric views of a preferred embodiment of the attachment 10 which reveals some internal features and the parts shown may also be preferred assembly subsections. Figures 2a and 2b show a first subassembly 100 is formed by a central cylindrical cage structure 60 and this is illustrated as having six elongate support struts 62. The six elongate support struts 62 extend between a collar 64 at the fluid inlet 20 of the central cylindrical cage structure 60 and an end wall 66 at a second end 24 of the central cylindrical cage structure 60. The collar 64 extends from a connection ring 68. The connection ring 68 functions to join the attachment 10 to the hot air styling device or similar device. The end wall 66 includes an outstanding ring 26 for attachment of the cool tip 32 via lugs 28 provided radially around the cool tip 32.

The fluid outlet is formed by the slots 50 extending from adjacent the collar 64 to the end wall 66 at a second end 24 of the central cylindrical cage structure 60. A second subassembly 110 is formed by six separate plates 40, as shown in Figure 2c. When the attachment is manufactured, the second subassembly 110 is attached to the first subassembly 100. In a preferred embodiment, each of the plates 40 are attached to a strut 62 forming extended plates 54 (see Figure 5) and this forms the elongate body 12 which extends between the collar 64 and the second end 24 of the central cylindrical cage structure 60. The elongate body 12 has a first end 14 adjacent the collar 64 and a second end 16 which is adjacent the end wall 66 of the central cylindrical cage structure 60. The elongate body 12 extends for as long as the struts 62, the plates 40 and the elongate slots 50. The collar 64 and connection ring 68 form part of the central cylindrical cage structure 60 but not the elongate body 12.

The collar 64 is flat and annular; the collar extends out from the elongate body and has a diameter which is greater than that of the connection ring 68, the elongate body 12 and the cylindrical cage 60. The collar 64 is substantially orthogonal to the longitudinal axis X-X of the attachment which is also the longitudinal axis of the elongate body 12.

In order to attach the first subassembly to the second subassembly each plate 40 is attached to a strut 62. Each strut 62 has several features which function to receive connection features located on the inner side of each plate 50. Specifically, three structural vanes 70 extend from a leading edge 62a of each strut 62 at regular intervals and join onto an outer face 72 of an immediately adjacent strut. An inner face 42 of each plate 40 has three indentations 44 located to receive the structural vanes 70. In a further embodiment, both ends of the outer face 72 of each strut includes a recess 74 which is suitable to receive a protrusion 46 positioned at both ends of the inner face 42 of each plate 40. In addition, each strut 62 includes a longitudinal flange 76 extending from the leading edge 62a. Each plate 40 has a cooperating longitudinal flange 48. In this embodiment, the cooperating longitudinal flange 48 is formed as a continuation of the three indentations 44 providing a localized thinning of the plate 40. The longitudinal flange 48 of the strut 62 is also effectively a thinned part of the strut 62. When the plate 40 is attached to the strut 62 an extended plate 54 (see Figure 5) is formed, the longitudinal flange 76 cooperates with the cooperating longitudinal flange 48 to position the plate 40 with respect to the strut 62. In a preferred embodiment, when the plate 40 is attached to a strut 62, the outer surface 72 of the strut 62 continues across an outer surface 52 of the plate 40.

In a preferred embodiment, additional fixing means, such as ultrasonic welding or gluing, can be utilized in addition to mentioned aids to attaching and positioning the plates 50. The parts are preferably welded along the length of the flanges and the three indentations 44. This provides an air seal at the leading edge 62a of each strut 62 forcing air to flow out of the elongate slots 50.

As shown in Figures 2b and 2c, a plurality of vanes 100 are located on the inner face 42 of each plate 40. Specifically, the vanes 100 are located along the leading edge 42a of each plate 40, in a transverse orientation to the longitudinal axis X-X of the attachment. In a preferred embodiment, the vanes 100 are spaced along the length of the plate 40 with gaps where positioning indentations 44 are present. From the first end 14 to the second end 16, the vanes 100 gradually decrease in length and depth and angle away from normal to the leading edge 42a of the plate 40.

The structural vanes 70 additionally have the function of directing the flow. Thus, the structural vanes have structural function and a flow turning function. The structural vanes 70 have a similar angle and profile to the vanes 100 adjacent each of the structural vanes 70.

The vanes 100 and structural vanes 70 are optimized for the drop in air pressure and the drop in air volume along the length of the elongate body 12 from the fluid inlet 20 to the second end 16 to provide air flow out of the slot 50 which is uniform in volume and direction along the length of the slot 50.

Figure 3 illustrates a side view of the attachment. The profile of the leading edge of each plate is non-parallel to the longitudinal axis X-X of the attachment. Specifically, each plate twists around the longitudinal axis X-X of the attachment forming a helical arrangement. Preferably, the slots curve by an angle of 45° from the longitudinal axis X-X of the attachment. In this example the slots 50 curve in an anti-clockwise direction from the first end 14 towards the second end 16. The slots 50 are formed between adjacent overlapping extended plates 54, 54a however, in order to form the curved slots, the plates 40 do not extend along the longitudinal axis of the attachment but also preferably curve by an angle of 45°.

In Figure 3, the vanes 100 located on the inner face of one particular plate 50 are visible through a slot between two adjacent plates. In the preferred embodiment shown, the diameter of the elongate body 12 is greater at the first end 14 than at the second end 16. Specifically, the plate arrangement flares outward towards the first end 14 of the elongate body 12.

This side view of the attachment in Figure 3 shows protrusions 76 regularly located on the connection ring 68 to enable a click-fit connection to the fluid outlet end of a hot air styling device or similar device. Alternative attachment options will be apparent to the skilled person, such as screw-fit or push-fit arrangements. A transverse cross-sectional view, along line A-A, through the elongate body 12 is shown in Figure 4. This cross-section shows the six extended plates 54 where each extended plate 54 includes one plate 40 and one strut 62 but does not cut through structural vanes 70 or vanes 100. A fluid outlet path 58 between an extended plate 54 and a consecutive extended plate 54a is not constant in width. Specifically, each extended plate 54 has an arc shaped cross-section of a smaller radius than a radius of the whole elongate body 12. Consequently, each fluid outlet path 58 has a minimum dimension at the associated outlet slot 50. Whilst the fluid outlet path 58 narrows towards each slot 50, the thickness of the extended plate 54 remains substantially constant. The longitudinal flange 76 and cooperating longitudinal flange 48 are consequently both approximately half the thickness of the plate 40 and strut 62.

The airflow exiting each slot 50 is tangential to the outer surface 54b of the extended plate 54 and joins with the airflow exiting the other slots thereby forming a continuous fluid path 78 around the circumference of the attachment. The airflow exiting the slots 50 is attracted to the curved surface of the attachment by the Coanda effect. This in turn causes hair that is presented to the attachment 10 to be influenced by the airflow to wrap around the cylindrical surface of the attachment 10. In particular the tips of a tress of hair presented to the attachment 10 are attracted to the outer surface of the attachment 10 and then the hair tress wraps around the attachment 10. As air is blown down the length of the hair, wet hair dries quickly. Advantageously, this wrapping process occurs without the use of bristles, and so the hair can slide off the attachment once it is dry or styled so there is no tangling.

The airflow exiting the slots is substantially normal to the slots 50 however, it is preferred that the airflow is angled towards the fluid inlet 20 by around 2.5 to 4.5°. In this example 3.5° has been used. A combination of the curved slot 50, vanes 100 and structural vanes 70 produces this angle of airflow. This causes hair to helix down the attachment, towards the fluid inlet 20 which enables curled hair to naturally fall off the attachment 10 when a user either removes the attachment 10 from the hair tress or switches the device off. A further transverse cross-section view, along line B-B of Figure 3, through the elongate body 12 is shown in Figure 5. This cross-section cuts through a vane 100 on each extended plate 54. The longitudinally helical nature of the fluid outlet slots can be seen, as the position of each extended plate 54 has rotated relative to Figure 4. Where a vane 100 on an extended plate 54 contacts the adjacent extended plate 54a , airflow is restricted or stopped.

Figure 6 shows a cross-section through the longitudinal axis of the attachment 10 thereby revealing the inner face of several struts 62. The inside of the cool tip 32 is hollow in order to provide a relatively cooler location for the user to touch or grasp the attachment. A gap between the underside of the cool tip 32 and the second end 16 of the elongate body 12 minimizes transfer of heat to the cool tip 32 and also has the advantage of allowing for manufacturing tolerances between parts.

The cool tip 32 comprises a handle 34 and an annular flange 36. The handle 34 is hollow and in this embodiment is filled with air to insulate the handle 34 from hot fluid flowing within the attachment 10. The annular flange 36 is provided with an annular indentation 38 to provide an air gap 80 between the second end 16 of the elongate body 12 and the cool tip 32 which extends circumferentially around the annular flange 36.

The elongate body 12 can be considered to have an outer wall 82 formed from the plates 50; the annular flange 36 is spaced from the outer wall 82. The air gap 80 is sufficiently sized so that the air gap 80 is continuous around the annular flange 36 even when manufacturing tolerances are considered.

In Figures 3 and 6, the flared profile of the elongate body 12 is apparent at the first end of the attachment. Such a flare is not present in all embodiments of the present invention. Whether there is a flare or not is determined by the relative diameters of the attachment and hot air styling device or similar device to which the attachment is attached. If the diameter of the attachment is less than that of the hot air styling device or similar device then there is a flare to both minimise turbulence and to enable a change in the diameter from the device to the attachment. Specifically, such a flare is included in an embodiment having a diameter of the elongate body of 30mm, but is not included in an embodiment having a diameter of the elongate body of 40mm. This flare functions to reduces turbulence and thereby aids initial attachment of the end of a hair strand to the first end of the attachment.

The elongate body 12 converges from the first end 14 towards the second end 16. The reduction in diameter extends from the first end 14 to a point Y and from point Y to the second end 16 the diameter of the elongate body 12 is constant. The purpose of the convergence is to provide a smooth transition from the diameter at the fluid inlet 20 to the diameter at the second end 16 of the elongate body 12. Any turbulence in air flowing into the attachment 10 is minimized which also reduces pressure loses in the attachment 10. This has the advantage of encouraging the tips of hair in a tress to attach to the outer surface of the attachment.

The top view of an exemplary attachment in Figure 7 illustrates that the collar 64 near the fluid inlet of the attachment has a greater diameter than the cool tip 32 at the distal end 30. The base view of an exemplary attachment in Figure 8 illustrates the overlapping formation of each extended plate 54.

The collar 64 has a number of functions. The collar 64 helps to keep hair on the attachment 10 when it is wrapped around the attachment 10 by providing a physical barrier for the hair and preventing hair from being wrapped around the attachment 10 or indeed an appliance connected beyond the collar 64. Another function is to protect the air flow around the attachment 10. The continuous fluid path 78 around the attachment 10 will entrain or draw air from outside of the slots 50. This entrained air is not necessarily tangential to the outer surface 54b of the extended plate 54 so could adversely affect the hair wrapping process. The collar 64, has a greater diameter than the first end 14 of the elongate body 12 thus, it acts as a barrier to air being entrained over the surface of an appliance towards the attachment 10.

Figure 9 shows a preferred embodiment of an inner face 42 of a single plate 40 having twelve vanes 100 positioned nearest a leading edge 42a of the plate 40. The vanes 100 are spaced within two main series of five vanes. Indentations 44, adapted to receive structural vanes 70, are found on the trailing edge 42b of the plate 40 located at the gaps between the series of vanes. The vanes 100 are positioned in a generally perpendicular orientation to the leading edge 42a of the plate 40. In a preferred embodiment, the vanes 100 located towards the upstream end of the attachment are positioned at an acute angle to the leading edge 42a of the plate 40 The preferred length of a vane 100 is substantially to fill the slot 50 formed by an overlap 84 provided between one extended plate 54 and the adjacent extended plate 54a.

The profile of each vane 100 is an aerofoil and is designed to direct flow from a first direction to a second direction out of the slot 50. Air enters the fluid inlet parallel to the longitudinal axis X-X of the attachment 10; this is the first direction. The air flowing through the attachment 10 will naturally turn from this axis towards the slot 50 but it is the combined action of the profile of the vanes 100 along with the curvature of the slots 50 on the air flow that produces the second direction of flow which, as previously described is preferred to be angled slightly towards the fluid inlet 20 as this encourages good wrapping of hair and curls that are easily removed from the attachment 10.

The vanes 100 may be regularly spaced along the length of the plate 50 however, in order to achieve even flow out of the slot 50 along the elongate body 12, it is preferred that the spacing is irregular and that the vanes 100 are more spaced at the first end 14 and closer together at the second end 16 of the elongate body 12.

In addition, as the volume and pressure of air flowing through the attachment 10 changes from the first end 14 to the second end 16 of the elongate body 12, the vanes 100 are progressively smaller from the first end 14 to the second end 16 of the elongate body 12. The angle of the vanes 100 with respect to the longitudinal axis X-X of the attachment 10 changes from the first end 14 to the second end 16 of the elongate body 12. It is preferred that the angle increases with respect to the longitudinal axis X-X of the attachment 10 from the first end 14 to the second end 16 of the elongate body 12.

Figure 10 is a side view of a plate 40 which shows the helical form around the longitudinal axis of each plate. The amount of helical rotation within a plate 40 is a function of a combination of features such as, but not exclusively, the number of plates, the diameter of the attachment, the profile of the vanes and the desired fluid outflow angle with respect to the longitudinal axis of the attachment.

Figures 11 to 17 show a second embodiment of the invention. In this embodiment, components illustrated and already described in relation to Figures 1 to 10 have like reference numerals. In this second embodiment, the diameter of the attachment 150 is 40mm. Thus, the diameter of the attachment 150 is larger than that of the connection ring 68 and the fluid inlet 20 into the attachment 150. The cross sectional area of the attachment 150 is greater than the cross sectional area of the fluid inlet 20. A diameter d2 of the attachment 150 is greater than the diameter df of the fluid inlet 20.

As air flowing into the attachment 150 experiences an increase in volume within the attachment at the first end 14 of the elongate body 112, some air will recirculate towards a ledge 160 produced between the connection ring 68 and the outer wall 182 of the attachment 150. Thus, some of the air exiting the slot 50 would flow towards the fluid inlet 20 unless the direction of flow were modified. In order that this recirculation does not affect the direction of flow of air out of the slots 50, at least the first vane 170, that being the vane adjacent the first end 14 of the elongate body 112 and adjacent the fluid inlet 20 is reversed with respect to all the other vanes 100.

This has two functions it firstly maintains the advantage that it provides flow out of the slot 50 which is uniform in volume and direction along the length of the slot 50 as with the previous embodiment and secondly it has one of the same functions as the collar 64 of the first embodiment, namely keeping hair on the attachment 150 by providing an air barrier at the first end 14 of the elongate body 112. Due to this air barrier, for this second embodiment, where the attachment 150 has a larger diameter than the fluid inlet 20 the collar 164 is the same diameter as the outer wall 182. As this attachment 150 has a greater surface area than the previously described attachment 10, hair is more easily attached to the outer surface 182 so the problem of adverse effects from entrained flow over the surface of an appliance towards the attachment 150 is less apparent.

The first vane 170 has an aerofoil shape and has a concave surface 172 and a convex surface 174. The vanes 100 also have a concave surface 102 and a convex surface 104. In order to turn air flowing out of the slot 50 towards the fluid inlet 20, the concave surface 102 of the vanes 100 is presented facing the fluid inlet 20 and this directs or channels the fluid towards the second direction in a smooth transition. Having a smooth transition reduces pressure losses, turbulence and noise within the attachment.

In contrast, the first vane 170 has the convex surface 174 facing the fluid inlet 20. This is due to the air recirculating towards the ledge 160, thus the concave surface 172 of the first vane 170 is still facing the air flow as with the vanes 100. The functionality is the same and the effect is similar it is the direction of fluid flowing that has changed.

The first vane 170 along with the vanes 100 are adapted to turn the fluid flowing in the attachment 150 from the first direction to the second direction out of the slot 50. As previously described, air enters the fluid inlet parallel to the longitudinal axis X-X of the attachment 150; this is the first direction. The air flowing through the attachment 10 will naturally turn from this axis towards the slot 50 and in this attachment 150, the air near the fluid inlet 20 turns further than required. In order to achieve even flow along the length of the attachment 150, as previously described, it is the combined action of the profile of the first vane 170, vanes 100 and with the curvature of the slots 50 on the air flow that produces the second direction of flow which, as previously described is preferred to be angled slightly towards the fluid inlet 20 as this encourages good wrapping of hair and curls that are easily removed from the attachment 10. A further feature of attachment 150 is that each strut 62 has a reinforcement. The first subassembly 100 is preferably injection moulded as a single piece. For attachment 10, as the elongate body 12 flares towards the fluid inlet 20 there is a natural tapering towards the second end 16 which is used during the manufacturing process to at least partially create the draft required to remove a central mould from the attachment 10.

For attachment 150, as the diameter &2 is greater than the diameter df of the fluid inlet 20 there is an undercut created during manufacture. For this reason, in attachment 150 there is localised thickening 162 of the strut 62 on a radially inner surface 162a at an inlet end 86 of the overlap 84.

The localised thickening 162 can be considered a reinforcing rib, protuberance or bulge which extends along the whole length of the strut 62. Adjacent the fluid inlet 20, the localised thickening 162 includes a chamfer or angled face 166 which guides fluid flowing into the attachment 150 from the connection ring 68 over the end of the localised thickening 162.

The curvature of the localised thickening 162 additionally directs flow over a trailing edge 62b of the strut 62 towards the overlap 84 and the slot 50.

Figure 18 shows an example of a hot air styling device 200 together with attachment 10. The hot air styling device 200 comprises a generally tubular handle 220 having an fluid inlet 230 and a fluid outlet 240 at opposing ends. At the fluid inlet 230 of the handle, an array of apertures 232 extends around and partially along the handle 220. Internally (not shown), a fan unit comprises a fan and a motor. In use, the motor drives the fan and air is drawn in through the apertures 232 of the fluid inlet 230, along an fluid flow path which extends through the length of the handle 220. The fluid is optionally heated by a heater (not shown) before exiting the hot air styling device at the fluid outlet 240. The fluid inlet 20 of the attachment 10 of the present invention is connected to the fluid outlet 240 of the hot air styling device 200 or a similar device and receives the fluid drawn in by the action of the motor. The fluid then exits the attachment 10 via slots 50. The appliance 200 may be connected to a power supply via a power cable or could house batteries within the handle 220.

The skilled person will be aware that fabrication and assembly of the present invention may be realized in many differing ways. In the embodiment shown in Figure 2, possible assembly subsections are shown as an elongate body 12 structure having six elongate support struts, six separate plates and a cool tip. However, the elongate body 12 may, in turn, be constructed of several further assembly subsections. In an alternative embodiment of the present invention, the elongate body 12 may comprise three fixed plates and a further three separate plates may be attached to the cage structure. Clearly, similar fabrication and assembly methods can be utilized independent of the number of plates present in an embodiment. A preferred method of manufacturing the attachment 10, 150 is by injection moulding however, this is not essential to the inventive concept and the skilled person will be aware of suitable alternatives.

The diameter of an attachment 10, 150 can be the same as that of the appliance to which it is attached or different. Some of the inventive features described herein are applicable regardless of the diameter, for example the spacing of the cool tip, the different subassemblies and the use of vanes.

Where the diameter of an attachment is shown as being different to that of an appliance to which it is attached, it is generally both the internal diameter and the external diameter that are different.

Vanes 100, 170 are shown as forming part of the plate 40 however, they could be formed as part of the strut 62. Indentations 44 adapted to receive to receive the structural vanes 70 are shown as being connected to the longitudinal flange 48 however they may be separated.

The invention has been described in detail with respect to a hot styling brush however, it is applicable to any appliance that draws in a fluid and directs the outflow of that fluid from the appliance including a hairdryer.

The appliance can be used with or without a heater; the action of the outflow of fluid at high velocity has a drying effect.

The fluid that flows through the appliance is generally air, but may be a different combination of gases or gas and can include additives to improve performance of the appliance or the impact the appliance has on an object the output is directed at for example, hair and the styling of that hair. Such additives include but are not limited to hairspray and serums for example.

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 care appliance comprising a body having a fluid inlet, a fluid outlet, a fluid flow path extending between the fluid inlet and the fluid outlet and at least one vane for directing fluid within the fluid flow path towards the fluid outlet wherein the body comprises at least two extended plates and the fluid outlet comprises a slot defined by an overlap between the at least two extended plates and wherein the at least one vane is positioned within the overlap between the at least two extended plates.

2. An attachment according to claim 1, wherein the body is elongate and extends along an axis.

3. An attachment according to claim 1 or claim 2, wherein the elongate body has a first end and a second end and the fluid inlet is at the first end.

4. An attachment according to claim 3, wherein the fluid outlet extends along the axis between the first end and the second end.

5. An attachment according to any preceding claim, wherein the at least one vane is an aerofoil.

6. An attachment according to any preceding claim, wherein the at least one vane directs fluid flowing in the fluid flow path from a first direction to a second direction.

7. An attachment according to claim 6, wherein the first direction is parallel to the axis of the body.

8. An attachment according to claim 7, wherein the second direction is 85° to 95° from the axis.

9. An attachment according to any preceding claim, wherein the at least one vane comprises a plurality of vanes extending from the first end of the body towards the second end of the body.

10. An attachment according to claim 9, wherein the plurality of vanes are irregularly spaced along the body.

11. An attachment according to claim 10, wherein the plurality of vanes are progressively closer together towards the second end.

12. An attachment according to any of claims 9 to 11, wherein the plurality of vanes are angled to the axis of the body.

13. An attachment according to claim 12, wherein the angle of at least some of the plurality of vanes differs from adjacent vanes.

14. An attachment according to claim 13, wherein the angle of the plurality of vanes with respect to the axis increases towards the second end.

15. An attachment according to any of claims 9 to 14, wherein the size of the plurality of vanes varies between the first end and the second end.

16. An attachment according to claim 15, wherein the plurality of vanes are progressively smaller towards the second end of the body.

17. An attachment according to claim 15 or claim 16, wherein each of the plurality of vanes has the same profile.

18. An attachment according to any preceding claim, wherein the slot is curved with respect to the axis of the body.

19. An attachment according to any preceding claim, wherein the at least one vane is substantially the same length as the overlap between the at least two extended plates.

20. An attachment according to any preceding claim, wherein one of the at least one vanes has a structural function as well as a flow directing function.

21. An attachment according to any preceding claim, wherein each extended plate is formed from a strut and a plate.

22. An attachment according to claim 21, wherein the slot is formed from a strut and a plate from adjacent extended plates.