Field of the Invention

The present invention relates to the field of hair styling devices. More particularly, the invention relates to a heated hair styling device having a brushing surface which combines a heat-sink having a relatively high contact area and a plurality of typical comb bristles. The device can typically, but not necessarily, be in the shape of a common brush.

Background of the invention

Most current hair styling devices, and particularly hair strengtheners, are limited by design to treat relatively small groups of hair at a time. In most cases hair pins are needed to isolate the treated thin hair layer or even force the use of two hands, one for brushing and the other to hold a blower, as a result the process is time consuming and inefficient. The current available solutions may also cause hair damage due to the use of chemicals or to the high pressure forced by iron strengtheners.

US 4,217,915 discloses a heated hair brush for facilitating curling and waving of hair during brushing, the hair brush has a body which has an outer surface which is of a good heat conducting material, in which bristles, in the form of plastic stubs, are inserted. An electrical heating element is in thermally conductive relationship with the heat conductive surface so that hair can be dried, straightened, or curled by contact with the heated body while being brushed, and without danger of contact with the skin due to the spacing effects of the bristles. The bristles are preferably molded integrally with a rail or strip inserted into grooves in the heated body. However, such heated hair brush has a limited contact area (i.e., a relatively low contact between the heat surface and the hair) and therefore it can treat only small portions of hair at a time. This results in a relatively long time consuming hair treating operation. Moreover, the bristles are relatively long and thereby they do not enable an efficient heat treating to the hair portion that is close to the scalp. Further disadvantages of the hair brush are due to the structure of the heating source, which is quite complicated as it uses a plurality of separated rails of electrical heating elements in form of spiral heating coils This structure has poor thermal contact with the outer surface limiting the energy power transfer from heat source to the hair which further limits the amount of hair treated and as a result slows treatment process.

Therefore, it is an object of the present invention to provide a hair styling device that simplifies hair styling and makes it easier for the user, and safer to the hair while significantly saving valuable time and frustration.

It is another object of the present invention to provide a heated hair styling device capable of treating relatively large portions of hair at a time.

It is a further object of the present invention to provide a heated hair styling device having a relatively large contact area with the treated hair.

It is yet another object of the present invention to provide a heated hair styling device having bristles protecting the scalp of the user from the high temperature area existing in the device and enabling free and fearless use of the styling device as if it were a regular brush.

It is yet a further object of the present invention to provide a heated hair styling device provided with a heat source attached to the heat surfaces with very low thermal resistance, such as a CPU heat sink conductor paste.

It is yet a further object of the present invention to provide a heated hair styling device safer to use and causes less damage to the hair. Other objects and advantages of the invention will become apparent as the description proceeds.

Summary of the Invention

The present invention relates to a heated hair styling device, which comprises: a) a heat sink having a top surface and a bottom surface, said heat sink comprising a plurality of knobs disposed at said top surface thereby forming a dense matrix structure resulting in a three-dimensional surface, which enables the treatment of a large amount of hair at a time; b) a heat source attached to said bottom surface for heating said heat sink; c) a plurality of bristles attached to said top surface and extending farther than the length of said knobs for enabling a safe and fearless use of the brush; and d) a housing made of low thermal conductivity material, for accommodating the heat sink and the heat source, which also can be used to grasp the hair brush or as its handle.

According to an embodiment of the invention, the bristles are attached to the top surface of the heat sink between the knobs, on top of the knobs, or by any combination thereof. The bristles can be made of flexible rigid material. According to some embodiments of the invention, the bristles are deployed in such a manner that they surround the knobs.

In one embodiment of the invention at least some of the bristles are made of, or coated with a material suitable to decrease friction and static electric charging, such as Teflon or Parylene. This may be particularly desirable for the central bristles, which are located on top of the knobs.

According to another embodiment of the invention, the top edges of the knobs are smooth.

In a further embodiment of the invention, the deployment knob density is high enough to force hair contact and/or to add friction for hair stretching. According to one embodiment of the invention, the bristles density is high enough to protect the scalp from the high temperature of the heat sink.

According to another embodiment of the invention, the housing further comprises a handle adapted to be comfortably gripped by a user hand.

In another embodiment of the invention the heat source extends from its basis into one or more of the knobs.

According to an embodiment of the invention, the heat source is attached to the bottom surface of the heat sink with very low thermal resistance using a thermal paste.

Brief Description of the Drawings

In the drawings:

- Fig. 1 schematically illustrates a cross sectional view of the heated hair styling device, in the shape of a hair brush, according to an embodiment of the invention;

- Fig. 2 schematically illustrates a perspective view of an exemplary heated hair styling device, according to an embodiment of the present invention;

Fig. 3 schematically illustrates an exemplary heat sink element; Figs. 4-6 schematically illustrate an exemplary implementation of a heated hair styling device, in the shape of a hair brush, according to an embodiment of the present invention;

- Fig. 7 schematically illustrates a cross sectional view of a heated hair brush, provided with a heat source portion that is located within one of the knobs, according to some embodiments of the present invention; and

Figs. 8 through 10 show different views of a particular embodiment of the device according to the invention. Detailed Description of the Invention

Throughout this description the term a "heat sink" is used to indicate a passive component that dissipates heat into the surrounding in a manner similar to a CPU heat sink structure. With respect to the present invention, the heat sink is designed to increase the surface area in contact with the medium surrounding it, such as the human hair. Of course, the choice of material, knobs (fins or other protrusion) design and surface treatment are some of the factors which affect the thermal performance of the heat sink. This term does not imply any particular shape, construction material or geometry, and invention is applicable to all suitable heat sinks. However, as will be appreciated by the skilled person in order to get optimal results the heat sink should be made of high thermal conductivity material.

Although the invention is not limited to any particular shape, in the description to follow it will be illustrated using a device in the shape of a hair brush, which is the most common shape for a device of this type, it being understood that the invention is not intended to be limited in any way to a hair-brush like shape. This term also does not imply any particular construction material or geometry, and the invention is applicable to any structure or design of hair styling devices that are capable of accommodating the heat sink.

In general, the invention uses a heat-sink structure (similar, for the purpose of illustration, to a heat-sink structure used to cool high power CPUs) in a hair straightener device and by this significantly improves the process of straighten the hair compared to the available prior-art solutions.

Reference will now be made to several embodiments of the present invention(s), examples of which are illustrated in the accompanying figures. Wherever practicable similar or like reference numbers may be used in the figures and may indicate similar or like functionality. The figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.

The terms, "for example", "e.g.", "optionally", as used herein, are intended to be used to introduce non-limiting examples. While certain references are made to certain example system components, other components and can be used as well and/or the example components can be combined into fewer components and/or divided into further components.

Referring now to Fig. 1, there is shown a front cross-sectional view of a heated hair brush 10 constructed in accordance with the principles of this invention. Hair brush 10 comprises a hair brushing portion which includes the following elements: a plurality of flexible or rigid bristles (as indicated by numerals 11 and 21), these bristles may be in different length, a high thermal conductivity heat sink 12 having a top surface and a bottom surface, and a heat source 13. The elements of the hair brushing portion are assembled into a housing portion 14, having a low thermal conductivity, such as a plastic body. The housing portion 14 is used also to cover the heat source 13 as well as optional electronics elements that can be used to activate and/or control the heat source 13. Exemplary electronic elements that can be used in conjunction with the heated hair brush of the present invention will be described in further details in particularly with respect to Figs. 2, 4 and 6.

In order to avoid heat from the housing a thermal insulating material, such as silicon can be provided to insulate the hot zone from other parts of the brush. Such insulation can also improve efficiency and save power. In prior art hairstyling devices (particularly straighteners), the housing temperature near the heater rises to more than 100°C shortly after power up. By applying an insulating material, as described above, the external temperature of the housing increases slowly and reaches lower temperatures. In one embodiment of the invention in which a silicon cage was provided the temperature increased slowly during 20 minutes to a final temperature of about 40°C.

According to some embodiments of the invention, a thermal paste can be used between the bottom surface of the heat sink 12 and the heat source 13 in order to increase the thermal conductivity between these heated elements (i.e., by filling microscopic air-gaps present due to the imperfectly flat and smooth surfaces of the components). The thermal paste can be any suitable viscous fluid substance, such as silicone thermal compound, metal (silver) thermal compound, and the like, which has far greater thermal conductivity than air. The thermal paste is used to aid the thermal dissipation via the heat sink 12.

The heat sink 12 includes a plurality of knobs 17 deployed on its top surface. The heat sink 12 is made of high thermal conductivity material (e.g., ceramic or aluminum) forming a pin-fin like heat sink structure or a dense matrix knob structure. According to an embodiment of the present invention, the top edges of the knobs 17 should be smooth to enable smooth penetration of hair to the hot area between the knobs and to avoid hair damages.

The heat source 13 can be any applicable heating element or high power resistor source such as Positive Temperature Coefficient (PTC), Negative Temperature Coefficient (NTC) like element, a metal ceramics heater (MCH), etc. A typical power consumption would be around 400 W, and as customary with appliances for personal use, the device is adapted to operate with both 110 and 220 V. According to some embodiments of the invention, in order to improve the heat transfer, the heat source 13 can be spread/inserted into some or all of the knobs 17, as shown with respect to Fig. 7 (e.g., this can be implemented by tiny power resistors).

The temperature attained by the device must be safe for the user and, a typical maximum temperature is around 210°C. However, as will be appreciated by the skilled person, a temperature gradient exists between the surface of the heater and the tip of the bristles that come into contact with the scalp and hair, so that the actual temperature felt by the user's body may be substantially lower than that measured at the heating surface. The skilled person will easily select construction materials for each case, which afford the desired temperature at each and every portion of the device.

The bristles can be made of any suitable material, as long as they withstand temperatures at which the device operates. For instance, if a maximum temperature of 210°C is desired for the surface of the heating device, it is desired that the material of which the bristles are made and/or coated be able to withstand continuous temperatures of up to 240°C. Illustrative and non-limitative examples of such suitable materials include, for instance, plastic materials, nylon, silicon and the like, or the bristle can be made of two different materials, such as an inner metallic core coated by a suitable coating material, for instance the above- mentioned plastic materials.

Similarly, the body 12 (Fig. 1) can be made of any suitable material that can function as a heat sink, but it is desirable in many cases to coat it with a suitable coating material, e.g. ceramics, to give it a more aesthetic form, as well as to protect it from wear. The flexible bristles 11, 21 are made of rigid low thermal conductor material such as plastic. The flexible bristles 11, 21 protect the treated body area (e.g., the scalp) from a direct contact with the relatively high temperature of the heat sink 12. Of course, in some implementations the temperature can be adjusted as in common hair straighteners which may reach up to 210°C or even more.

Heat from the heat source 13 (e.g., which can be powered by 220VAC or 110VAC or batteries) is delivered to the body of heat sink 12. Heat source 13 has good thermal contact with the heat sink body 12 - as an option by adding the thermal paste, which allows to efficiently delivering the energy to the heat sink body 12. As heat sink with high thermal conductivity, efficiently transfer the heat from the heat source to its surface.

The top surface area of the heat sink 12 is very large related to the heat sink size thanks to its matrix knob structure. This enables the delivery of high thermal power to the hair during the brushing. As aforementioned herein before, the top edges of knobs 17 should be smooth in order to avoid damages to the hair and also to enable smooth penetration of hair to the hot area between the knobs 17. Fig. 3 schematically illustrates an example of a high density knobs matrix heat sink 12 that can be used with a hair styling device of the present invention.

The density of the knobs 17 should be high enough to force good hair contact and, together with the bristles 11 and 21, it adds friction for the hair stretching operation. The bristles 11 surround the knobs 17 at top surface of the heat sink body 12 from all sides and they should extend higher than the length of knobs 17 (e.g., the length of some of the bristles 11 can be higher than the height of the knobs 17). This arrangement has two goals: to protect the user and the treated area (such as the scalp) from the high temperature of the heat sink 12 and to effectively brush the hair. The bristles density, 11 and 21 in the illustration, should be high enough (e.g., about 10mm) to protect the scalp from the heated heat sink.

According to an embodiment of the present invention, the heat sink 12 is build from knobs with different heights, thus one or more of the bristles are attached on top of the lower knobs (e.g., as shown by the combined of the short knob 22 and the short bristle 21 in Fig. 1). This structure enables bristles that are long enough to cool while still keeping the longer knobs very close to the scalp.

According to some embodiments of the present invention, all the knobs having the same height and all the bristles are a few millimeters higher than the knobs. In this embodiment, some of the bristles can be connected directly to the top surface of the heat sink (e.g., between the knobs 17) while the rest of the bristles are connected on top of at least some of the knobs (e.g., on top of knobs 22). In such configuration the bristles have two different lengths (i.e., short and long), but they still extend farther then the length of the knobs 17 or 22.

Fig. 2 shows an example for a hair brush 10 that can be used in conjunction with the invention. The hair brush illustrated in this figure is particularly convenient to use because it has a handle 15.

As best seen in Fig. 2, the bristles 11 are deployed on the outer surface of the heat sink body 12, thus the bristles 11 and the knobs 17 are longitudinally spaced along the outer surface of the heat sink body 12. The bristles 11 as well as the knobs can be formed into several sets of rows (usually symmetrical rows) as usually deployed in common hair brushes.

As aforementioned, the hair brush 10 is provided with a heat source 13 for heating the heat sink body 12. For example, common electrical elements such as electrical wires 16 can be used to deliver electrical energy to the heat source 13. Although it will be understood that any suitable heating means may be used including rechargeable batteries or other suitable power sources. In the embodiment shown in the drawings, the electrical wires 16 are operatively connected to the heating source 13 within the interior of hair brushing portion of hair brush 10 (as indicated by the dotted line in Fig. 2).

It will be understood that each of the bristles 11 and knobs 17 may be shaped in a variety of profiles and lengths in addition to being spaced at different distances relative to the central rows.

According to an embodiment of the invention, the hair brushing portion of hair brush 10 is not rotatable relative to handle 15, although with respect to some configurations it could be made rotatable (e.g., a cylindrical brush) without detracting from the advantages of the invention. For example, in case of a cylindrical brush, additional bristles shall surround the heat sink to protect touching it from the sides.

Referring now to Figs. 4-6, an exemplary implementation of the heated hair brush 10 is shown in accordance with an embodiment of the present invention. In this embodiment, the long bristles 11 are deployed in such a manner that they surround the entire knobs 17 and 22, while a few shorter bristles 21 are deployed between the knobs 17. The arrangement described in those figures results in a relatively large surface area, such that the extent of the heated area is uniform along the entire top surface area of the heat sink 12, which makes it possible to effectively treat a large amount of hair at a time.

Fig. 5 schematically illustrates a detailed view of the heat sink 12. As it can be easily seen in this figure, the knobs 22 are shorter than knobs 17 and they are combined with the shorter bristles 21. Fig. 6 schematically illustrates a cross sectional view of the heated hair brush 10 of Fig. 4. In this figure, the heat source 13 can be seen.

In this exemplary embodiment, the heated hair brush includes an operating switch 23 for selecting the temperature and turning the heat source on/off. The hair brush 10 may further comprises one or more visual indicators (e.g., such as LED 24 for indicating the state of switch 23, and LEDs 25 for indicating the temperature selected as seen on the handle 15 of brush 10 in Figs. 4 and 6), and may further include other indicators or controls, such as a heat level display, temperature control switch, etc.

Figs. 8 through 10 show three different views of a device 80 according to one embodiment of the invention. The various elements are indicated using the same reference numbers as in Fig. 4, for ease of reading. When comparing the embodiment of Figs. 8 - 10 with that of Fig. 4, it can be seen that bristles are provided in this embodiment on each of the knobs 22, while in Fig. 4 only some of the knobs are provided with bristles. Different devices, having different bristle density can be provided, e.g. for different types of hair or uses.

The invention allows for great flexibility in the final shape, additional elements and improvements. For instance, the device on the invention can be provided in essentially tubular shape, as many conventional styling brushes. With a brush having a circular cross-section and tubular shape the bristles and knobs are disposed on the surface in a continuous manner. Such a brush is suitable, for instance, for styling the hair by creating curls, as opposed to simply straightening the air as hearing before described, although of course a tubular brush of circular cross-section can be used for both purposes.

An additional example of an accessorized device of the invention is a device as described, for instance with reference to Figs. 8 - 10, which is provided with regular bristles on the surface opposed to the heated bristles and knobs. In this way, the user can use the same device for heated and non-heated styling at the same time.

In another embodiment of the invention fanning means are provided within the housing of the device, and openings are provided on its heated surface (for instance, at 13 of Fig. 2), to allow for a stream of hot hair to be delivered to the hair during brushing.

It should be appreciated that the styling device of the invention does not necessarily have to be made in one piece and, in certain embodiments of the invention, various elements, such as the handle, can be replaced for different purposes with alternative elements of different shapes.

According to one embodiment of the invention a movement detection element is included in the device, which is used to control the device, for instance to shut it down or to switch it to our saving, standby mode, if no movement is detected for a given length of time. Movement detection elements are conventional in the art and, therefore, are not described herein in detail, for the sake of brevity. Such movement detection devices can be, for example, and accelerometer such as those commonly found in smartphones broadly available on the market, which can be housed, for instance in the handle of the device.

The advantages of the invention are achieved by the arrangement of the heat sink that includes a heat sink like structure with high hair contact high thermal conductivity that efficiently transfer high heat power to human hair and relatively high power heat source to supply the energy needed. This arrangement enables free grooming and heating of hair efficiently and without the need to divide the hair to small portions as usually done in hair iron straightener and other prior-art solutions. The hair straightening advantages of the invention results in an easily hair brushing and by significantly saving valuable time with respect to prior art solutions.

All the above description and examples have been given for the purpose of illustration and are not intended to limit the invention in any way. Many different mechanisms, methods of analysis, electronic and logical elements can be employed, all without exceeding the scope of the invention.