FR2616636A1 - Hot (heating) comb for drying and straightening hair - Google Patents

Abstract

The hot (heating) comb for drying and straightening hair consists of an injection-moulded plastic comb surrounding a core of small cross section, heated electrically. Locking of the assembly is ensured by the handle. This comb, which is more specifically designed for short hair, has profiled teeth which retain the hair. The hot (heating) core acts on the hair in the zone included between its root and the base of the teeth where it is retained.

Description

 The present invention relates to a heating device, electric, for drying and straightening the hair regardless of their length.

 To dry the hair, forming, straightening, are traditionally used: hair styling, blower brushes and / or heating, blower and / or heating combs or even metal combs, non-electric that must be heated.

 Hair styling iron: it is a heating electric iron composed of a handle for example plastic and a heating core, for example chromed, on which is fixed a metal blade shaped half-shell intended to pinch the locks of hair that we want to dry and form.

The heating portion is integral with the handle, it can not have a rotational movement about the major axis, regardless of the handle. The power supply is fixed. The diameter is about 12 to 15 mm.

 This device is primarily intended for users having hair long enough to be formed and / or straightened by wick. Thus a user simply wishing to dry his hair quickly will have little interest in using this type of device. In addition, if the user has short hair, the iron clamp system is inoperative because the hair can not go around the heating core and be blocked by the metal blade to pinch. The treatment of lousy hair per chews also assumes a skillful practice of "blow-dry" and a sufficiently long available time.

Brush: it is a non-heating, round brush, with a high diameter (greater than 15 mm)> mounted on a hot ventilation system to dry the hair or to form them The brush-can be attached to the handle or it may be an interchangeable tip.According to the two embodiments, the brush is dependent on the handle and can not have a rotational movement, the handle remaining stationary.The power system is in the fixed or rotary embodiments ( device allowing the ventilation unit to turn without causing the son
Drying is achieved by the heat of the ventilated air. The hair is not in contact with a heated surface, which lengthens the time required for drying and desired shaping. This type of embodiment is unsuitable for users with short hair, since the hair must be long enough to self-lock around the central core of the brush to be held and uniformly heated by the air. As for the iron to comb, a practice of "blow-dry" is necessary for optimum use of this device or it is necessary to involve an external person, especially for the non-visible parts of the hair. The treatment of the hair is wick by wick, which causes wastes of time. In use the device is rotated along the longitudinal axis, which can be annoying at the power cable. If it remains fixed, it will be twisted. Due to the drying process used (ventilation of hot air), the handle is bulky and heavier than achievements based on processes using resistors.

 Heating brush: this is a round brush, mounted around a heating core equipped with a resistance. The brush is generally integral with the handle, without the possibility of rotation about the longitudinal axis of the device. According to the embodiments, the feeding target is fixed or rotating.

The brush is either empoilée (it has then a diameter of about 15 to 20 mm) or plastic <its diameter is less than 20 mm>. Sometimes brushes of different diameters are proposed.

 When using these devices, the hair is guided by the teeth and is wrapped around the heating core, self-locking as soon as the hair has made a complete turn. The essential problem that arises is the necessary length of the hair for the effective use of the device. If the hair is not long enough, the action of rotation of the brush in the hair does not result in a blockage of hair close to the heating core and therefore does not dry properly. These brushes having relatively large diameters (15 to 20 mm), people with short hair can not be satisfied users. The fact that it is a brush, also poses the problem of 8brushing; it is necessary to know how to make a "blow-dry" to use this device, and it is also necessary to have a sufficient time.

Since the device must rotate along the major axis, if there is no rotating power cable, the wire will undergo twisting, which may damage it.

 There are also embodiments of brushes both blowing and heating, incorporating both heating processes.

 Blower combs: The blower combs correspond to the use of a comb attachment in the "hairdressing set" (ventilation block sold with several interchangeable tips: air diffusers, air concentrator, comb, round brush. ..). The comb end consists of a half-shell of plastic, hollow and supplied with hot air, which is traversed throughout its length by a row of teeth, more or less spaced according to the achievements, in the center of the half-shell in a cross section.

 The maneuverability of these devices is not always very good because the comb tips are mounted on ventilation blocks often large diameter (40-50 mm) and heavy because of the blower device and volume constraints imposed for user security. This large diameter is even more troublesome than here can touch the scalp by preventing the total penetration of teeth in the hair.

 Heating Comb: Some brands use the term comb to refer to cylindrical heating constructions with a block of teeth made of plastic and completely surround the heating core. The diameter of these devices is between 10 and 15 mm.

 Comb metal to heat: the special feature of these combs is the lack of integrated heating device.

The comb is composed of 2 parts. A metal part constituting the comb itself, part that must be heated via an external heat source, with teeth centered or off-center according to the embodiments.

The diameter of the metal core is 8 mm. The handle, the second component, is made of wood, it is cylindrical and is screwed on the metal part of the device. The nucleus and teeth are one piece, quite heavy and unprotected and insulated.

 When using a metal comb, the temperature can not be controlled: the user may burn his hair or not heat enough to give them the desired shape. Apart from the handle, only nonmetallic part, all the others are heated and may burn the user if there is contact with the skin and / or the scalp, and in particular with the toothed part which is closest to the hairline when working the comb. The metal part being full, and heavier than the handle, there is a strong imbalance in favor of the heated part which is an additional risk of contact and therefore burn. Due to this solid part, the device is heavy and therefore unmanageable. The use of this comb requires an external heat source, which is an additional constraint. This comb loses its effectiveness because the teeth are not profiled, there is the same spacing between the teeth over their entire length. The teeth are rough machining, leaving sharp angles and traces of tools that can hurt the hair.

 The device according to the invention overcomes the disadvantages raised above.

 FIG. 1 shows the heating comb with exploded sections showing the heating core, its electrical resistance and a part of the comb fixed to the core by a dovetail device (the teeth are not all represented for clarity of the drawing) .

 Figure 2 shows the heating comb provided with teeth overmolded on the core with exploded to see the grooves and the inside of the heating core (the teeth are not all shown for clarity of the drawing).

 Figure 3 shows the heating comb, with asymmetric teeth, which is exploded to show how the handle locks in translation and rotation the heating core.

 Figure 4 is a longitudinal section of the comb Figure 3 passing through the axis of the handle and the axis of the bore of the metal core.

 Figure 5 shows teeth viewed from the front in plan on their heating core.

 FIG. 6 is a section along a plane perpendicular to the axis of the bore of the core passing between two teeth of FIG. 5.

 The device consists of a plastic comb <1) fig.1 whose base (2) teeth is integral with a metal mass (3), located generally on the opposite side to that of the teeth relative to their base <2 ), of small section, conducting the heat, having inside an electrical resistance <4) which heats it. This device allows a "blow-dry" on short hair. When combing through the hair, they come to brake on the base of the teeth and the area of the hair, located between the base of the comb and their roots, comes into contact with the hot part. The hair in contact with the hot part are then under tension, which makes it possible to dry them quickly, and possibly to straighten them.The interest of such a device is to be active from the base of the hair and until that its end escapes from the base of the teeth where it is braked. The built-in electric heater (c4) allows on the one hand to bring calories where they are needed, during the "blow-dry", and on the other hand to guarantee a temperature controlled so that there is no deterioration hair.

 The metal mass (3) and the resistor (4) constitute the heating core of the device, of generally elongated substantially cylindrical shape, the section of which depends on the shape chosen for the comb <1).

 The main axis of the resistor <4) is substantially parallel to the directlon of the generatrices of the cylindrical part of the metal core (3). The electrical resistance (4) is of cylindrical shape whose section must be a function of the same section of the metal core so that the flow of heat is distributed in a balanced manner between the various zones of the heated surface. One way of balancing the temperatures is to have a highly conductive metal between the various zones of the heating core (3), and the closest possible contact between the core (3) and the resistor (4).

 The length of the resistor (4) must be in correspondence with the length of the core (3) so that there is a balanced heat input to the various areas of use.

 The teeth of the comb (1) are preferably injected plastic so that we can profile them cheaply and tighten their spacing at the base to brake and pull the hair to the approach of the heated part. The materials that can be used are numerous, we will mention for the record polypropylene, polycarbonate, polyamide, polyesters. The teeth of the comb (1) are fixed relative to the heating core (3). The attachment points are such that they do not generate contact between the hair and the core. One possible embodiment is to make a dovetail groove (5) machined in the metal core, parallel to the generatrices in order to slide the comb (1). The comb (1) is then made of teeth interconnected by a barrette (6) in the form of a male dovetail fitting in the groove (5) made in the core (3). When the core (3) is hot, it causes an expansion of the bar (6) of the comb (1) which expands more than the core (3) and causes the locking of the assembly. The role of the teeth of the comb (1) is to guide the wicks towards and on the heating core t3). Between each tooth, at the level of the heating core (3), it is preferable that the heating core (3) is apparent to heat and dry the hair. In the case just described, this poses a problem because the barette ( 6) which holds the teeth together isolates the teeth at their base (2), and- the heating core (3) is not protected in the zone (7) which is opposite to them. Another solution would be to over-mold (f ig.2> each tooth (8) would be independent and be anchored individually in a groove (9) of the core (10) .It would then be necessary to perform a machining of the core (10) to anchor the teeth (8), which is very expensive, is to mold the aluminum parts by injection to obtain the grooves <9) anchoring with the molding; the good quality of the comb requires practically to mold the core into 2 half-shells, which at the time of overmolding can generate material passes through the joint planes. Indeed, for the comb to be effective requires a metal core (10) of small section. The housing of the electrical resistance (11) is of much smaller section than the core (10) with a ratio of length to high section.The mold that would make the core (10) in one piece, would include to make the housing of the resistance (11) a long piece of small section which would be destroyed by flexion from the first metal injections. Hence the choice of a solution with two half-shells. To avoid having material in the housing of the electrical resistance (11), it is therefore necessary to have parts having precise ribs, which is difficult to obtain by the technique of injection molding.

 Although the two solutions that we have just stated answer globally the problem, we prefer a third solution that takes the advantages of each of the previous solutions.

 The comb therefore consists of a plastic part <12) fig.3 whose teeth (13> fig.6 completely surround the metal heating core (14) and which are interconnected by a connecting bar (15) whose the form is used for its anchorage The tooth (13) completely surrounding the heating core (14) protects the scalp from direct contact with the metal A way of not losing the contact surface is to sacrifice one of the faces < 16) of the comb to hook the teeth <13) between them and to dedicate the entire other face (17) to the heating function. This is actually a loss of performance because the comb can only be used on one side. But we can compensate for this defect by improving the contact surface (17) of the side not having the connecting bar (15) of the teeth, making an asymmetrical comb (fig.6).

 This embodiment uses Hvirgular section teeth, completely surrounding the heating core (14), having a concave zone (19) and a convex zone (17), whereby the concave zone (19) is used to hook the teeth together. a connecting bar (15) because the concave area (19) is never in contact with the hair anyway, thus avoiding the anchoring of the teeth (fig.1) and overmoulding (fig.2) , and leave the convex part (17) fig.6 free so that the hair is in contact with the core (14) The comb (12) fig.3 can be molded apart, It is threaded by translation on the core heater (20) whose profile is adapted to that of the tooth.One of the problems may be, depending on the profiles, to prevent the comb from rotating around the core (20) under the effort it undergoes in use It is possible to combine this profile with a dovetail anchorage (fig.1), as described above, located in the neutralized zone (19) fig. 6.

 According to a preferred embodiment the core (20) fig.3 is extruded aluminum and non-circular section, the comb (12) has a section in the form of a comma, that is to say that the teeth are asymmetrical, and that for the convex zone (17) fig.6 is as close as possible to the hair root and as long as possible. The concave zone (19), which is of little use for heating the locks, is used for hooking the teeth (18) together.

 The teeth (22) fig.5 are preferably made of plastic. They are profiled, their thickness (21) is not constant over the entire length and widens towards the base (23), to ensure a good cannalisation of the hair. At their end (24), the spacing (25) between two consecutive teeth (24) and (26) is wider, in order to easily select a lock consisting of a maximum amount of hair. Approaching the heating core (27), the gap (28) decreases to brake and compress the wick to stretch and press against the core (27). Then, at the core (27), the gap (29) between two consecutive teeth (24) and (26) widens again so that the sheet of hair is more spread and more uniformly heated.

 The teeth of the comb (17) fig.6 surround the heating core to prevent direct contact between the heated portion and the skin and / or the scalp. The comb (12> fig.3 is mounted on the heating core (20) and is rotated by its shape matching that of the core, but also at the handle (30) in which it is clamped and fixed.

The end (31) of the comb <12) is closed to abut on the end of the metal core (20) and may have a protrusion <32) fig.4 forcing into the profile (33). ), in the housing (34) of the resistor (35), to improve by expansion the anchoring of the comb (36) at its end (37). This provides additional water tightness. The other end (38) of the comb (36) completely covers the metal core (33) in the area between the last tooth (39) and the handle (40) to protect the wearer from burns and improve teeth holding. in rotation.Il ends at its entry in the handle (40), by a cylindrical zone (41). It is anchored in the handle (40) by annular excrescences (42) surrounding the cylindrical zone (41), on which are tightened the two half-shells (43) and (44) of the handle. It is desirable that this zone is waterproof; one way to operate is to use for the annular protuberances (42), trapezoidal sections permitting the blocking and the achievement of tightness by clamping the two half-shells <43) and (44).

 The comb thus designed may be molded in one piece by injection into a preferably heat resistant plastic material of the type described above.

 Made preferably of aluminum, to obtain a good conduction of heat, the outer portion (33) of the heating core has, in a preferred embodiment, a section in the form of "shortened comma" (15) fig.6 to maintain the fixed comb and prevent a rotational movement on his part. It is of constant section and can be produced by extrusion, like profile and cut to the desired length. This aluminum profile comprises a cylindrical bore (45) preferably of revolution intended to accommodate a resistance <35) preferably of cylindrical cylindrical revolution, which will be maintained inside its housing with plugs (46) for example silicone.

 The metal core (33) fig.4 with its resistance <35) is threaded into the comb (36), and the end of the bore is forced into the end (32) of the comb. The length of the core (33) is very substantially greater than that of the comb (36) so as to be anchored in the handle (40) of the comb where it is held between half-walled games (47) and ( 48) integral with the half-shells (43) and (44) of the handle and each reproducing the corresponding portion of the profile (14) fig.6 of the core (33) fig.4. When the two half-shells (43) and (44) of the handle (40) are tightened, each set of half-walls (47) and (48) enclose the core (33) to keep it in rotation.It is necessary to provide in the half-shells (43) and (44) of the handle (40), stops (49) preventing the core from sinking deeper into the handle, by disengaging the comb (36). These stops (49) nevertheless allow the passage of the power supply son (50). They can be integral with a set of half walls (48) located in the vicinity of the end (51) of the core (33).

 The heating core (33) is thus maintained gracie with the comb (36) and the handle (40) which are also integral thanks to the circular protuberances <42>.

 The comb (36) working mainly in shear, it is desirable to put a set of half walls (47)> in the vicinity of the cylindrical zone (41) of anchoring revolution of the comb (36) in the handle (40), to constitute a main point of transmission of efforts. A second support (48) located in the vicinity of the end (51) of the core makes it possible to absorb the force due to the torque. The zone between these two support points (47) and (48) must remain free to absorb elastic flexure stress peaks.

 The resistor <35) is preferably self-regulating with PTC cells, so that when the temperature increases, the electrical power that it absorbs decreases. This feature gives the user a very important safety for his hair. The maximum temperature thus controlled should be around 70-80 *. The maximum power absorbed by the resistor is around 20 Watt.

 The handle (40) of the device also has the role of maintaining fixed the heating core (33) and the comb (36). Of circular section, for example, it may be made of plastic material injected into one of the following materials polyamide, polycarbonate, propylene loaded, polyethylene terephthalate or any other material having good heat resistance and low thermal conductivity. According to a particular embodiment, it consists of two half-shells <43> and <44> injected plastic whose inner structure is intended to maintain the heating core (33) by sets of half walls <47) and <48 ) and the comb (36) by circular grooves (42) .The two half-shells (43) and (44) are held against one another by estimate (52) located in the vicinity of the transmission zones of the efforts . It is desirable to have two screws in the vicinity of the anchor (42) of the comb (36) passing on both sides of the metal core (33); their maximum efficiency is when their housing (53) fig.3 is integrated in the set of half walls (54) for wedging the core (20) located in the immediate vicinity of the comb attachment area <55> in the handle ( 30). Similarly it is desirable to have at least one screw (52) fig.4 in the vicinity of the set of half walls (48) located in the vicinity of the end (51) of the metal core (33); the housing of this screw <52> is nevertheless located at a sufficient distance from the end <51) of the core, on the opposite side to the comb (36), so as not to hinder the passage of the electrical wire <50) the resistor (35) which bypasses it.

The power supply of the comb is through an opening at the end (56) of the handle <40) and through which passes the power cable. It may for example include relay pads to make self-sufficient electrical resistance and power cable. But, without major inconvenience, in order to reduce costs, solder the power cable to the power supply wires.

 It is important to note that the realization of the handle in two half-shells (43) and (44) held by screws (52) makes it possible to make the comb (36) interchangeable for the purpose of either replacing it as a function of the nature and length of hair combs with teeth of dimension and profile differ, or replace a broken comb.

Nevertheless, this is not a very easy operation and tools must be available. An improvement of the apparatus consists in making it easy to disassemble the comb by producing, for example at its cylindrical end of revolution (41), a filament. The end of the handle then has a circular abutment on which is wedged a sliding nut on the handle (40) and coming to screw on the threaded end of the comb. This system is the same in principle as that which is generally used to attach a garden hose to a faucet. Other systems are to penetrate the comb in the handle where it closes; just press a button slightly above the handle to unlock. Under these conditions the heating core supports almost all efforts.

 Whatever the system used for the connection of the comb and the handle, it should be remembered that the interchangeability of the comb (36) fig.4 is favored by the rigidity and the good anchoring of the heating core <33) in the handle (40). ). That is to say that the more the comb is intended for short hair plus the core (33) is of small section, the more it is necessary that the comb (36) participates in the transmission of efforts and therefore have a rigid anchorage (42). Under these conditions, flexibility in interchangeability will be lost.

Claims (4)

 l) The heating comb for drying and straightening the hair is characterized in that it consists of an injected plastic comb having profiled teeth, such that two consecutive teeth have a smaller gap (28) at their base than at their end <25), integral with a heating core of small section, containing an electrical resistance, disposed generally on the opposite side to the teeth relative to their base.  2) The heating comb for drying and straightening the hair according to the preceding claim is characterized in that the teeth <18), are interconnected by a barette (15) which serves to anchor the comb on the heating core (14) , and come surround the heating core.  3) The heating comb for drying and straightening hair according to any one of the preceding claims is characterized in that the heating core (33) is a heat conducting metal profile, obtained by extrusion, which goes into a housing of the comb closed at its end (37), while the two half-shells (43) and <44) of the handle (40) lock in translation and rotation both the comb (42) and the heating core in (47), <48> and (49).  4) The heating comb according to any one of the preceding claims is characterized in that the core consists of a convex portion (17) and a concave portion (19), the teeth (18) are dissymmetrical and connected between they by a connecting bar (15) housed in the concave portion (19) of the core.