AU779575B2 - Hairdryer - Google Patents

Description

P/00/011 28/5/91 Regulation 32(2)

AUSTRALIA

Patents Act 1990

COMPLETE

COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: HAIRDRYER The following statement is a full description of this invention, including the best method of performing it known to us

HAIRDRYER

FIELD OF THE INVENTION The present invention relates to the field of personal care products, and in particular the design of hairdryers.

BACKGROUND

In economically advanced countries, a hairdryer is a common appliance for most households. These hairdryers are connected by an electrical cord to a mains power point and typically having various heat settings. Air is heated in such devices via a coil system that lines the periphery of a chamber between the fan and the outlet nozzle, so that heating is predominantly achieved via heat transfer through space. One problem with these existing hairdryers is that they are not very energy efficient.

A further problem is that there is a risk of electrocution with existing hair dryers, particularly considering that the hairdryer is typically used in "wet areas" in 15 households, such as the bathroom. When used in wet areas, it is all too easy for the corded hairdryer to fall into a bath or sink of water and hence possibly cause electrocution. This problem is often enhanced by the fact that the hairdryer is SI" powered via a mains supply power point, and hence the location of its use is limited by the positioning of power points.

20 There is therefore a need for an improved hairdryer, and the present invention seeks to alleviate or ameliorate at least one problem of the prior art.

e SUMMARY OF THE INVENTION According to one aspect, the present invention provides a hair dryer including: a fan; a motor for powering the fan; a battery power source for providing power to the motor; a casing having an outlet nozzle, the casing further including a multilayered structure having a first heat resistant polymer layer, a second aluminium layer, a third foam layer and a fourth aluminium layer; and one or more heating coils, wherein the one or more heating coils traverse a cross-sectional area of the outlet nozzle, such that a generated airstream is materially heated by contact with at least one of the one or more heating coils.

la According to a preferred embodiment of the present invention there are a plurality of heating coils which are serially connected to a heat setting switch, such that different numbers of heating coils may be activated for different heat settings.

*o Preferably, the one or more heating coils substantially cover the entire cross-sectional area of the outlet nozzle.

In a particular preferred embodiment there are three heating coils connected to the switch, and one coil is activated for a low heat setting, two coils are activated for a medium heat setting and three coils are activated for a high heat setting.

It is preferable that the plurality of heating coils are arranged in the output nozzle substantially equidistantly along the length of the nozzle.

The hair dryer may further include an output nozzle grille having a smaller radial plane than the smallest radial plane of the chamber of the hair dryer.

Preferably, the coil activated for the low heat setting is the coil nearest the output nozzle grille.

The hair dryer may also include an airflow baffle coupled to the fan in order :to facilitate unidirectional airflow through the chamber.

15 One key advantage of the present invention is that it allows users to utilize the device in any location. In this regard, the user is not limited to using the unit in the proximity of a mains power point, but may use it in any other location.

S" A further advantage of the present invention is the design of the coil system of the present invention, which allows for more efficient heating than 20 standard hairdryers.

•Another advantage of the present invention is that since the unit runs on a DC power supply, the risk of electrocution is eliminated during use of the S" invention, as it is not connected to a mains power point.

o 5 A still further advantage of the present invention is that not only may it be recharged from a mains power supply, but the unit may also be charged through a motor vehicle cigarette lighter. Therefore, the present invention is particularly useful for travellers.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to the accompanying drawings, in which: Figure la illustrates a cross section of a hair dryer according to an embodiment of the invention, corresponding to section A-A of Figure 1 b.

Figure lb illustrates a front view of the hair dryer shown in Figure la.

Figure ic illustrates a view of a coil aggregate in the direction A, being a component of the hair dryer shown in Figure 1 a.

Figure 2 illustrates a schematic diagram of the circuitry of a hairdryer according to an embodiment of the invention.

Figure 3a illustrates a top view of a battery charger for the hair dryer of the present invention.

Figure 3b illustrates a front view of the battery charger of Figure 3a.

Figure 3c illustrates a side view of the battery charger of Figure 3a.

Figure 4a illustrates a front view of a mains adapter for the hair dryer of the present invention.

Figure 4b illustrates a side view of the mains adapter of Figure 4a.

DETAILED DESCRIPTION With reference to Figure la, a hair dryer 1 according to an embodiment of the present invention is illustrated. Two switches control the operation of the 15 appliance. The first switch 2 is an on/off switch and the second switch 3 is a heat level switch. The heat level switch 3 may have any number of different heat level settings. The connectivity of these features is also apparent in Figure 2.

S°The on/off switch 2 is connected to a power supply 4 via an amplifier/rectifier and an overload/cut-out switch 6. The overload switch 6 is a safety feature. The e.:e 20 power supply 4 in Figure 1 is a removable and rechargeable battery, which is attached to the hair dryer via attachment clips 7 on the side of the battery casing.

e This battery may be charged whilst attached to the hair dryer or on its own.

Also, to allow the device to be charged from various sources, charger input 2 8 is provided which, for example, may allow the appliance to be charged from a car cigarette lighter.

Alternatively, the appliance 1 may be charged from an AC source. In this regard, referring to Figures 4a and 4b, front and side views respectively of an AC adapter that may be used to charge the device via charger input 8 is illustrated.

The battery unit 4, as shown in Figure la has a wide base, which creates a convenient base rest whilst the dryer is not in use.

Alternatively, rather than having a wide base, the base may be uniformly rectangular. This base may then be inserted into a stand 19, such as is illustrated in top, front and side views in Figures 3a, 3b and 3c respectively. The rectangular base of the dryer would be inserted into the cavity of the stand, and held in position via spring contacts 20. This stand may also serve as a recharging stand for the dryer by connecting the stand to a power source in a known manner.

The on/off switch 2 is further connected to the motor 10 powering the fan 11. The motor powered fan 11 is coupled with an airflow baffle 12, which facilitates constant uni-directional airflow through the chamber.

The appliance also includes a filter 13 held by filter support 14. An inlet vent 15 is also provided, which facilitates the in-flow of air and is preferably removable to aid in cleaning the filter 13.

The appliance 1 in Figure la also includes a coil system according to an embodiment of the present invention. In the illustrated embodiment, the coil system includes three distinct coil aggregates 16 equidistant along the length of the nozzle of the heating chamber. For reasons of safety, the aggregates are 15 isolated from the casing and each other using bracket spacers.

Each coil aggregate is arranged so that the cross sectional area of the chamber is wholly covered, or at least substantially covered with coil. In this way each aggregate substantially traverses the path of the airflow at their respective points in the chamber. By configuring the coils in this way, the air generated by 20 the fan flows through the aggregates, and heating of the air is materially achieved through direct contact with the coil surface, before being emitted from the chamber. Heating in this manner is generally more efficient than heating through heat transfer in space.

2 A further improvement in heating efficiency is achieved by establishing a heated chamber. In this regard the boundaries of the chamber is the area from the fan to the terminal aggregate, which is the aggregate that remains heated regardless of the heat setting, as it is the first one activated. In the present embodiment of the invention, the terminal aggregate is the one furthest from the fan and closest to the outlet where air is emitted from the unit.

Since the terminal coil aggregate substantially cover the cross-sectional surface area of the nozzle, a chamber is effectively established which facilitates heating of the air-stream generated by the fan. Heating of the air in the chamber is facilitated by heat transfer in space. Therefore, it is to be appreciated that the coil configuration of the present invention heats air primarily by direct contact with the heating coils, efficiency is further improved by space heat transfer within the heating chamber that is established.

Therefore, the air coming off the fan is at room temperature until it heats up prior to emission from the chamber. It is to be appreciated that the hottest air inside the chamber will be that portion in closest proximity to the activated heating coil or coils.

To further improve the effectiveness of this heating chamber, insulation of the chamber is provided to reduce the effect of undesirable heat loss from the chamber to the outside surface of the dryer unit.

Now with reference to Figure la, in one embodiment of the invention, the heat level switch 3 has three settings. On a first setting, being a low heat setting, only one of the coil aggregates 16 is heated. Preferably the heated coil is the coil closest to the outlet, which may be termed the terminal coil. On a second heat 15 setting, being a medium heat setting, two of the coil aggregates are heated.

Preferably, in addition to the terminal coil, the centre coil aggregate is also switched on. Finally, on the high heat setting, all three aggregates are heated. In this way the one or more heated coil aggregates heat the airflow created by the fan 11 primarily via direct contact by virtue of being placed directly in the path of 20 the airflow.

°o It is to be appreciated that this configuration is an improvement over the disclosed arrangement of coils that merely line the periphery of the outlet nozzle.

oo0 This is because with such existing arrangements air passes through a large S central volume of space devoid of coil. Hence air in this central volume relies S 25 upon heat transfer through space in order to be heated. With the present invention, however, placing the coils directly in the path of the airflow, the air is heated more efficiently through direct contact with the coil surface and also through heat transfer in the heating chamber that is created.

With reference to Figure 1 b, in another embodiment of the invention, the grille 18 on the front nozzle of the appliance 1 has a small surface area when compared with the equivalent cross-sectional area of the chamber. This feature provides for increased pressure inside the chamber, as it ensures a certain 6 degree of air backflow into the chamber thus giving the air more time to contact the heated aggregates 16 and ultimately, more efficient heating prior to emission.

In another embodiment of the invention, in addition to the number of aggregates that are heated depending on the heat setting, it is also possible to vary the speed of the fan motor. Therefore, for the low heat setting, the motor could run on a low setting, and then the speed could increase for the higher heat settings.

A further feature of the appliance that assists in the efficient heating operation, is that of insulating the casing of the unit with an R1 heat rated insulation 17 or equivalent. Preferably this insulation is applied to the inside of the unit's casing. This insulation 17 reduces the transmission of the heat between the inside of the unit and the outside tangible surface of the dryer.

:In a preferred embodiment of the invention, an 8mm insulation and casing arrangement is provided. In this regard, the entire casing of the dryer unit is 15 composed in this matter, including the chamber, which is isolated from the o circuitry using the same material. This material is preferably formed as follows: Layer 1 heat resistant polymer 2 mm thick (external layer); •:*'"Layer 2: aluminium 1 mm thick; Layer 3: foam 2 mm thick; Layer 4: aluminium 1 mm thick.

This combination of materials provides reasonable heat preservation properties and also facilitates ease of manufacture, due to the malleability/workability of the inner layers between the polymer. These materials are arranged in such a way so that Layer 1 forms the outside tangible surface of the dryer unit and Layer 4 forms the inside casing (chamber).

These materials are also lightweight. In this regard it is preferable that the unit is compactly constructed so that it will weigh no more than two thirds that of a cordless drill. This will facilitate use of the device for extended periods of time.

Variations and additions are possible within the general inventive concept as will be apparent to those skilled in the art.

In this regard, it is to be appreciated that any number of aggregates may be used.

Claims (9)

1. A hair dryer including: a fan; a motor for powering the fan; a battery power source for providing power to the motor; a casing having an outlet nozzle, the casing further including a multilayered structure having a first heat resistant polymer layer, a second aluminium layer, a third foam layer and a fourth aluminium layer; and one or more heating coils, wherein the one or more heating coils traverse a cross-sectional area of the outlet nozzle, such that a generated airstream is o•materially heated by contact with at least one of the one or more heating coils.

2. The hair dryer of claim 1 wherein the one or more heating coils oo• substantially cover the entire cross-sectional area of the outlet nozzle. *i

3. The hair dryer of claim 1 or 2 wherein there is a plurality of heating coils 15 which are serially connected to a heat setting switch, such that different numbers of heating coils may be activated for different heat settings.

4. The hair dryer of claim 3 wherein three heating coils are connected to the switch, and one coil is activated for a low heat setting, two coils are activated for a medium heat setting and three coils are activated for a high heat setting. 0 0o

5. The hair dryer of claim 1 or 2 wherein three heating coils are connected to the switch, and one coil is activated for a low heat setting and three coils are activated for a high heat setting.

6. The hair dryer according to any one of claims 1 to 5 wherein there are a plurality of heating coils arranged in the output nozzle, which are substantially equidistant along the length of the nozzle. 8

7. The hair dryer according to any one of claims 1 to 6 further including an output nozzle grille having a smaller radial plane than the smallest radial plane of the chamber of the hair dryer.

8. The hair dryer of claim 6 as appended to claims 4 or 5 wherein the coil activated for the low heat setting is the coil nearest the output nozzle grille.

9. The hair dryer according to any one of claims 1 to 8 further including an airflow baffle coupled to the fan in order to facilitate unidirectional airflow through the chamber. A hair dryer substantially as herein described with reference to Figure la. S DATED this 2 nd day of December 2004 GEORGE YACOUB WATERMARK PATENT TRADE MARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA *o3 P18163AU01 RLT/CAG/SLB o* *o•