FIELD OF INVENTION

The invention relates to hair dryers apparatus. The invention has particular, although not exclusive relevance to hair dryers and to hair dryer attachments.

BACKGROUND TO THE INVENTION

A hair dryer provides a stream of air. The stream of air may be used to remove moisture from hair and/or style the hair.

A hair dryer typically comprises a main body comprising an air inlet, an air outlet, a fan and a heater. The fan draws external air into the main body via the air inlet and blows out a stream of air through the air outlet. The heater is arranged between the air inlet and the air outlet to heat the air flow so as to provide a hot stream of air.

The majority of hair dryers require the user to attach a nozzle onto the air outlet to focus the airflow into a flat plane. This process requires the user to clip or unclip the nozzle from the hair dryer and then store the nozzle when not in use. The nozzle itself has a fixed shape having an air inlet that attaches to the air outlet of the hair dryer and an air outlet that is connected to the nozzle air inlet by a body that is shaped to shape the air flow into the desired flat plane.

SUMMARY OF THE INVENTION

The present invention also provides a hair dryer apparatus comprising: a housing having an air inlet and an air outlet and defining an air flow channel between the air inlet and the air outlet through which air can pass; a focussing member mounted within the air flow channel; wherein the housing and the focussing member are arranged for relative movement between an extended position in which the focussing member focuses the air flow from the air outlet and a retracted position in which the focussing member does not focus the air flow from the air outlet (or focusses the air flow from the air outlet to a lesser extent). A user actuation mechanism may also be provided for actuation by a user to allow the relative movement between the focussing member and the housing between said retracted position and said extended position. The focussing member may be fixed within the housing and the housing comprises a sleeve that can move to change the relative position of the focussing member and the air outlet of the hair dryer apparatus; and/or the focussing member can move relative to the air outlet.

The focussing member may be arranged so that when in the retracted position, the hair dryer apparatus can deliver an air flow having a first air flow profile and so that when in the extended position, the hair dryer apparatus is arranged to deliver a second air flow profile that is narrower (more focussed) than the first air flow profile.

The focussing member may have a serrated leading edge and in some embodiments, the focussing member may comprise an offset stop member (such as a bar) positioned beyond the leading edge of the focussing member to ensure a space is provided between the leading edge of the focussing member and the user’s head or hair during use.

The user actuation mechanism may comprise a manually operated switch or slider, a latch and a manually operated button to release the latch, a solenoid, a diaphragm. Where a latch is used, the latch, when engaged, will typically hold the focussing member and the housing in the retracted position and when the latch is released, the focussing member can be positioned in the extended position. The latch may be spring loaded or the device may rely on air pressure to force the focussing member to be deployed in to the extended position.

Typically, the focussing member will have at least one and preferably two convex surfaces that focus the air flow passing over the convex surfaces. The convex surfaces may be an upper surface and a lower surface that meet at a leading edge of the focussing member. The focussing member may also have first and second lateral side portions and wherein at least one (and preferably both) of the first and second lateral side portions is concave. This helps to reduce turbulence caused by air flow over the focussing member.

The apparatus may further comprise a shroud that surrounds a front portion of the housing (including the air outlet) and that defines a secondary air flow channel between an inside surface of the shroud and an outer surface of the housing through which, during use, air is drawn. The air drawn through this secondary air flow channel can help to cool the user actuation mechanism and can help to contain the focussed and hot air produced by the hair dryer.

9 According to the invention, the apparatus may be a nozzle that is for attachment to a conventional hair dryer. In this case the air inlet of the apparatus would be configured to conform to the size and shape of the air outlet of the conventional hair dryer to which the nozzle is designed to be attached. Alternatively, the apparatus of the invention may be a hair dryer. In this case, the hair dryer will further comprise a fan for drawing air in through the air inlet, a motor for turning the fan and a heater for heating air drawn into the hair dryer. The hair dryer may be a hand held hair dryer that comprises a handle. The handle is typically located on the underside of the main body and extends substantially perpendicularly to a longitudinal axis of the main body.

The present invention also provides a hair dryer apparatus comprising: a housing having an air inlet and an air outlet and defining an air flow channel between the air inlet and the air outlet through which air can pass; a focussing member mounted within the air flow channel; wherein the housing and the focussing member are arranged for relative movement between a retracted position in which at least a majority of the focussing member is within the air flow channel and an extended position in which the focussing member extends out of the air flow channel beyond the air outlet to focus an air flow passing through said air flow channel and out said air outlet.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will now be described with reference to the following drawings in which:

Figures 1a and 1b are perspective and cross-sections of a hair dryer incorporating a focussing member in a retracted position;

Figures 1c and 1d are perspective and cross-sections of the hair dryer shown in Figures 1a and 1b with the focussing member in an extended position;

Figure 2a is an air flow plot illustrating the air flow through the hair dryer shown in Figure 1 with the focussing member in the retracted position;

Figure 2b is an air flow plot illustrating the air flow through the hair dryer shown in Figure 1 with the focussing member in the extended position; Figure 3a is a side view of an alternative front portion of a hair dryer that includes the moveable focussing member and an offset bar located in front of the focussing member;

Figure 3b is a plan view of the front portion of the hair dryer shown in Figure 3a; Figure 4a is a side view of an alternative front portion of a hair dryer that includes a moveable focussing member having a serrated leading edge;

Figure 4b is a plan view of the front portion of the hair dryer shown in Figure 4a; Figure 5a is a plan view of an alternative front portion of a hair dryer that includes a moveable focussing member having a serrated leading edge and shaped side portions to reduce turbulence;

Figure 5b is a perspective view of the front portion of the hair dryer shown in Figure 5a;

Figure 5c is a side view of the front portion of the hair dryer shown in Figure 5a;

Figure 5d is a front view of the front portion of the hair dryer shown in Figure 5a; and Figure 6 is an air flow plot illustrating the air flow through a further alternative front portion of a hair dryer illustrating the effect of providing a shroud around an air outlet.

DETAILED DESCRIPTION OF THE DRAWINGS

Various features are shown in the drawings. These features are applicable to all aspects of the invention and may be used in any combination.

Figure 1a is a perspective view of a hair dryer 1 and Figure 1b illustrates a cross- sectional view of the hair dryer shown in Figure 1a. The hair dryer 1 comprises a housing 3 having an air inlet 5 at one end of the housing 3 and an air outlet 7 at the opposite end of the housing 3. The housing 3 defines an air flow channel 8 between the air inlet 5 and the air outlet 7. A fan unit 9 and its associated motor unit 11 are mounted within the housing 3 for drawing air in through the air inlet 5, and forcing air through the housing 3 and out the air outlet 7. A heating element 13 is mounted downstream from the fan unit 9 for warming air which passes over the heating element 13. As with conventional hand held hair dryer, the hair dryer 1 also comprises a handle 15 for a user to hold the hair dryer 1. As would be understood by those skilled in the art, the hair dryer 1 may be powered by battery, mains electricity or a low voltage power supply (not shown).

The hair dryer 1 also includes a focussing member 21 that is mounted within the housing 3 and that is moveable between: i) a retracted position in which most of if not

A all of the focussing member is located inside the housing 3 to reduce focussing of the air flow by the focussing member 21; and ii) an extended position in which the focussing member 21 extends out from the housing 3 to focus the air flow from the hair dryer 1. As shown in Figure 1, the focussing member 21 has a convex upper surface 23 and a convex lower surface 25, that converge (or meet) at a leading edge 27 of the focussing member 21.

Figures 1a and 1b illustrate the hair dryer 1 when the focussing member 21 is in the retracted position and Figures 1c and 1d illustrate the hair dryer 1 when the focussing member 21 is in the extended position. Figure 2a is an air flow plot illustrating the air flow through the hair dryer 1 when the fan 9 is on and the focussing member 21 is in the retracted position and Figure 2b is an air flow plot illustrating the air flow through the hair dryer 1 when the fan 9 is on and the focussing member 21 is in the extended position. The air flow is represented by arrows, with the speed of the air flow represented by the size and boldness of the arrows.

As can be seen from both Figures 2a and 2b, the focussing member 21 sits in the centre of the air outlet 7 so that air can flow around the focussing member 21 in the gap between the housing 3 and the focussing member 21. As shown in Figure 2a, when the focussing member 21 is retracted within the housing 3, it hardly (if at all) affects the air flow from the air outlet 7, such that the profile of the air flow 31 from the hair dryer 1 is dictated by the shape of the hair dryer housing 3 at the air outlet 7. However, as shown in Figure 2b, when the focussing member 21 is in the extended position, the air flow is focussed by the focussing member 21 to form a narrower air flow 33 from the hair dryer 1.

The air flow 31 from the hair dryer 1 when the focussing member 21 is in the retracted position is more defuse and spread out such that the peak air flow velocity from the hair dryer will be lower (compared to when the focussing member 21 is in the extended position) as the air flow is spread out over a larger area. The hair dryer 1 would be operated in this mode by the user for blast (diffuse) drying of hair to get it from a wet state to a dry state at lower temperatures. When the focussing member 21 is deployed (moved to the extended position), the air flow 33 follows the convex upper and lower outer surfaces 23 and 25 of the focussing member 21 (coanda effect) thereby focussing the air flow. The focussed air flow 33 has a higher velocity and temperature at the leading edge 27 of the focussing member 21 - thereby

F> replicating the operation of a conventional focussing nozzle attachment. The hair dryer 1 would be operated in this mode by the user for styling the user’s hair.

In this embodiment, the focussing member 21 is slideable from the retracted position to the extended position and a user operated actuation mechanism 41 is provided to allow the user to move the focussing member 21 between the extended position and the retracted position. Many different user actuation mechanisms 41 may be used. In the hair dryer shown in Figure 1, a slider mechanism 43 that is coupled to the focussing member 21 is provided that, when not actuated by the user, engages with a channel 45 in the housing 3 to hold the focussing member 21 in its current position within the housing 3. However, when the slider mechanism 43 is pressed by the user, the slider mechanism 43 disengages with the channel 45 and can slide along the channel 45. As the focussing member 21 is coupled to the slider mechanism 43 (preferably integrally formed therewith), the focussing member 21 moves with the slider mechanism 43 as the slider mechanism 43 is moved along the channel 45. The slider mechanism 43 may engage with the channel 45 at any position along the channel 45 - thereby allowing the focussing member 21 to be positioned at any position between the retracted and extended positions (infinitely adjustable). This allows different amounts of focussing to be achieved by the hair dryer between a maximum amount of focussing (when the focussing member 21 is in the extended position) and a minimum amount of focussing (when the focussing member 21 is in the retracted position). In an alternative arrangement the channel 45 and slider mechanism may be arranged so that the focussing member can only be held in one of a number of positions. A similar slider mechanism 43 and channel 45 may be provided on the other side of the hair dryer 1. In this embodiment, the channel 45 is open at the air outlet 7 end of the housing 3 - thereby allowing the focussing member 21 to be removed from the housing of the hair dryer 1 if desired.

The hair dryer housing 3 and the focussing member 21 are typically made of a hard plastics material that can withstand the normal operating temperatures of a hair dryer (typically up to about 185 degrees Celsius) whilst being light weight and durable for everyday use.

Alternatives and Modifications

A detailed embodiment has been described above of a new hair dryer apparatus. Various alternatives and modifications to the above apparatus will now be described. fi As mentioned described above, various user actuation mechanisms 41 may be provided for allowing the user to move the focussing member 21 between the retracted and the extended positions. Examples include:

1) A spring loaded latch may be used. In this case, the user can push the focussing member 21 into the retracted position where the latch holds the focussing member 21 in position. Then when a user presses a release button, this releases the latch from the focussing member 21 and a spring pushes the focussing member 21 forward into the extended position.

2) As another alternative, the same latch may be used as the above alternative, but instead of relying on a spring to force the focussing member forward into the extended position, the hair dryer may use the force from the air flowing through the hair dryer when it is switched on to cause the focussing member 21 to be pushed forwards into the extended position.

3) Similarly, the focussing member 21 may be freely moveable within the housing 3 and a moveable stop may be provided the position of which can be set by the user at any position between the retracted and extended positions. In use, when the hair dryer is turned on, the air flow through the hair dryer pushes the focussing member forward until it hits the moveable stop.

4) A ratchet and pawl mechanism may be used such that when the user turns a knob on the side of the hairdryer, this causes the focussing member to be moved in and out of the housing 3 depending on the direction of rotation of the knob.

5) A solenoid may be provided with electronics or a switch to allow the user to activate the solenoid to pull or push the focussing member 21 in or out of the housing 3.

6) A thermal wax applicator may be used that has a diaphragm to move the focussing member 21 in and out of the housing.

7) The focussing member 21 does not need to move in a linear path between the retracted and extended positions. The focussing member 21 may be arranged to move along a curved path. For example, the channel 45 may be curved so that the focussing member 21 moves to the bottom (or top) of the housing 3 when in the retracted position. Further still, the focussing member 21 may rotate about an axis to move between the retracted and extended positions. The inventor has noticed that during trials when the hair dryer 1 shown in Figure 1 is used by a user, they often hold the leading edge 27 of the focussing member 21 too close to the user’s head which means that the air flow passing over the upper surface 23 and the air flow passing over the lower surface 25 of the focussing member 21 do not have time to converge before hitting the user’s hair. The inventor solved (or at least alleviated) this problem by adding an offset bar at the end of the leading edge 27 to prevent the leading edge 27 of the focussing member 21 getting too close to the user’s head. Figures 3a and 3b illustrate the front part 51 of a hair dryer having such an offset bar 53 to ensure that there is a gap 55 between the leading edge 27 of the focussing member 21 and the user’s head. The front part 51 of the hair dryer shown in Figure 3 may be integrally formed with the rest of the hair dryer or it may be designed as a separate attachment that is to be attached to the air outlet of a conventional hair dryer. That is, the front portion 51 defines its own housing 3 having an air inlet 5, air outlet 7 and flow channel 8 there-between. The advantage of the front part 51 being integrally formed with the rest of the hair dryer is that the attachment is less likely to be lost and it doesn’t need to be separately stored when not attached to the hair dryer.

In the above embodiments, the leading edge 27 of the focussing member 21 was a straight edge. The inventor has found that when the focussing member 21 is in the extended position, the air flow passing over the upper surface 23 and the air flow passing over the lower surface 25 create turbulence when these flows meet at the leading edge 27. The inventor has found that this turbulence can be reduced by making the leading edge 27’ serrated, as illustrated in Figure 4. Specifically, Figure 4a shows a side view of a front part 51 of a hair dryer that has a focussing member 21 that can move between a retracted position and an extended position (Figure 4 shows the focussing member 21 in the extended position) and Figure 4b shows the same front part 51 of the hair dryer but shown in plan view. As can be seen from Figure 4b, the leading edge 27’ of the focussing member 21 in this alternative is serrated. The focussing member 21 is moveable between the extended position and the retracted position by the slider mechanism 43 as before. This front portion 51 may be integrally formed with the rest of a hair dryer or it may be a separate part in the form of a replaceable nozzle that mounts onto the air outlet 7 of a conventional hair dryer.

The inventor also identified that the sides of the focussing member 21 experience high turbulence due to the convergence of high velocity airflows at the sides. These fi side areas can also be designed to try to minimise this turbulence. One way that this can be done that the inventor found particularly effective is to create concave side portions of the focussing member 21 to smooth the merging of the air flows as they leave the hair dryer. Figures 5a to 5d illustrate a front portion 61 of a hair dryer incorporating a preferred focussing member 21 that has been shaped to reduce turbulence. Specifically, Figure 5a is a plan view of the front portion 61 of the hair dryer, Figure 5b is a perspective view of the front portion 61 of the hair dryer, Figure 5c is a side view of the front portion 61 of the hair dryer and Figure 5d is an end view of the front portion 61 of the hair dryer.

As most clearly shown in Figure 5a, the leading edge 27 of the focussing member 21 is serrated to reduce turbulence along this leading edge. In the design shown in Figure 5, the leading edge 27 also includes a flattened portion 62 which helps to straighten out the air flowing over the upper surface 23 and over the lower surface 25 before these flows merge after the leading edge 27. The sides 63 and 65 of the focussing member 21 have scooped out (concave) portions 63a and 63b and a flattened portion 63c on the left side and scooped out (concave) portions 65a and 65b and a flattened portion 65c on the right side that help to flatten and even out airflow in the side areas of the focussing member 27 thereby helping to reduce turbulence in these side portions. Again, the front portion 61 shown in Figure 5 can be integrally formed with the main housing 3 of a hair dryer or it can be a stand-alone attachment that is designed to attach onto the air outlet of a conventional hair dryer. Although not shown in Figure 5, the front portion 61 will have a user actuation mechanism 41 that the user can actuate to allow the focussing member 21 to move between the retracted and the extended positions.

In the embodiment described with reference to Figure 1, the air outlet 7 of the housing 3 of the hair dryer 1 was a conventional outlet having a generally oval shape. The shape of the air outlet 7 is not important for the invention and in alternative arrangements it can have a circular or square shape if desired. Further, a shroud is preferably mounted to the air outlet 7 end of the housing 3 that defines a secondary air flow channel surrounding the outer surface of the air outlet end of the housing 3. This shroud can make use of the venture effect to draw cooler ambient air through this secondary air flow channel. This cooling air can help to cool the user actuation mechanism 41 that the user touches to move the focussing member 21 between the retracted and extended positions. This cooling air flow also acts to contain the hot and focussed air flow 33 output by the hair dryer. Figure 6 schematically shows the front part 71 of a hair dryer having the focussing member 21 and having a shroud 73 that surrounds the air outlet 7 end of the housing 3. As can be seen from Figure 6, the shroud 73 surrounds the air outlet 7 where high velocity air is exiting the hair dryer (when it is powered on). This region of high velocity air has a lower static pressure than ambient air pressure, which causes air to be drawn down the secondary channel 75 (defined between an inner surface of the shroud 73 and an outer surface of the housing 3) which helps to cool the housing 3 - particularly in the area of the housing 3 where the user actuation mechanism (41 not shown) is located. The cool air drawn down the air flow channel 75 surrounds the hot air flow 33 produced by the hair dryer and helps to contain the hot flow and thereby to maintain the flow profile of the hot air as it moves away from the hair dryer. As before, the front part 61 may be integrally formed with the hair dryer housing 3 or it may be a separate part that is configured for attachment to the air outlet end of a conventional hair dryer.

In all of the embodiments and alternatives described above, the focussing member 21 has been moveable relative to the housing 3. It is also possible for the focussing member 21 to be fixed in its position within the main part of the housing 3 and for the housing 3 to be telescopic or to have a sleeve that moves relative to the focussing member 21. In this case, the housing would effectively move the position of the air outlet 7 relative to the focussing member 21 so that the focussing member 21 is at least mostly within the housing 3 (in the retracted position) or extends out beyond the air outlet 7 to perform the focussing function described above (in the extended position). The user actuation mechanism 41 would then operate to move the housing 3 relative to the focussing member 21. Of course, both the focussing member 21 and the housing 3 may be able to move relative to each other if desired, although this is not preferred as it overcomplicates the design of the apparatus.

Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of the words, for example “comprising” and “comprise”, means “including but not limited to, and is not intended to (and does not) exclude other moieties, additives, components, integers or steps.

Throughout the description and claims, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise. m Features, integers, characteristics or groups described in conjunction with a particular aspect, embodiment or example, of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.