Abstract:
A hair iron having an array of substantially parallel heating prongs, wherein the distance between at least two of the prongs can be decreased while maintaining the prongs in a position substantially parallel to one another. An insulating guard surrounds the perimeter of each heating prong. The hair iron may further comprise two non-heating end units on either side of and substantially parallel to the heating prongs. The distance between the heating prongs can be decreased by actuating a drive mechanism. The insulating guards protect a user from high temperatures of the heating prongs. Further claimed is a method of styling hair using a heating device having substantially parallel heating prongs and manipulating the device to reduce the distance between at least two prongs while maintain the prongs in a position substantially parallel to one another.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention is in the field of hair grooming accessories. Hair grooming accessories are often used to straighten and style hair, however such activities can become overwhelming when the stylist is presented with curly or bristly hair. The effects of compression and heat application to straighten this type of hair are well-known in the art and have been incorporated in a variety of prior grooming accessories. 
         [0002]    Examples of earlier electrically heated combs are disclosed in the U.S. Pat. Nos. 3,760,821 and 4,702,265 issued to W. T. Weddington, U.S. Pat. No. 1,034,859 issued to G. Anderson, U.S. Pat. No. 1,536,669 issued to C. Grant, U.S. Pat. No. 2,590,447 issued to S. R. Nord, Jr., et al. Other types of heated combs and pressing devices are shown in U.S. Pat. No. 1,523,461 issued to J. Swan; U.S. Pat. No. 1,861,040 issued to J. E. B. Williams; U.S. Pat. No. 2,406,490 issued to D. A. Day; U.S. Pat. No. 2,545,885 issued to H. F. Jackson; U.S. Pat. No. 2,598,330 issued to E. Wilson; and U.S. Pat. No. 3,065,759 issued to F. Lewis. The apparatus taught by the aforementioned patents fall within the chief categories of hinged opposing-tong “flatiron” design, or alternatively, the pick-like “pressing comb” design. Each category presents several disadvantages. 
         [0003]    For instance, the amount of hair captured by flatirons widely varies, and a user of such a device is likely to capture large-volume hair locks that absorb heat and pressure unevenly. When large locks of hair are captured by flatirons, the outer strands receive more heat and pressure than the inner strands. Distribution of heat and pressure is distributed more evenly when smaller locks of hair are captured, but capturing smaller locks of hair with a flatiron increases the overall time and effort required to style the entirety of a person&#39;s hair. 
         [0004]    Pressing combs, such as those disclosed in U.S. Pat. No. 3,742,964 to Newbern and U.S. Pat. No. 4,126,143 to Schroeder, include a score of fixed teeth that capture a multitude of small-volume hair locks. However, it is difficult, if not impossible, for a user of a pressing comb to exert pressure and heat evenly over the captured hair. The heat and compression is exerted onto the locks of hair by skillfully and carefully maneuvering and manipulating the comb. There are a limited number of stroke types the comb&#39;s user may employ, such as drawing hair sideways through the comb, and also twisting the hair, similarly to twirling spaghetti onto fork tines. 
         [0005]    Both categories of combs necessarily incur repetitive strokes that typically repeat treatment on previously-treated strands. Additionally, neither category offers a stylist the ability to straighten strands of hair strands close to their roots. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    The present invention heats hair with consistent pressure in a time-efficient manner. The hair iron of the present invention includes a plurality of substantially parallel heating prongs wherein an outer portion of each prong includes a thermally insulating guard. The hair iron of the present invention further includes a drive mechanism utilized during a first and second mode of operation of the hair iron. During the first mode of operation, the drive mechanism moves at least one prong so as to reduce the distance between at least two of the prongs, so as to apply heat and pressure to hair positioned between the prongs. During the second mode of operation, the drive mechanism moves at least one prong so as to increase the distance between at least two of the prongs and release the hair. During both the first and second modes of operation, all prongs remain substantially parallel. 
         [0007]    The prongs may comprise heating plates or other suitable structures for applying heat and pressure to hair. Each heating plate may include a heating element. The hair iron may further comprise a system of electrical wiring and circuitry that provides an energy source to the heating elements. In certain embodiments, the heating prongs may further include an air space between each heating plate and thermally insulating guard. Non-heating end units on either side of the heating prongs may further protect a user from the high temperatures of the heating prongs. 
         [0008]    The present invention further includes a method of styling hair using a device having substantially parallel heating prongs where an outer portion of each prong comprises a guard. The user would place hair in the hair iron device and manipulate the hair iron to reduce the distance between heating prongs, thereby applying both pressure and heat to the hair. The user could further manipulate the device to increase the distance between prongs to release the hair from the hair iron. 
         [0009]    The present features of the hair iron and its various embodiments enable a user to straighten hair close to the hair roots. The various embodiments of the invention additionally convey an unprecedented high degree of maneuverability, which allows a user to execute a greater number of styling strokes and thereby achieve a greater variety of hairstyles. Related objects and advantages of the present invention will be apparent from the following description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a front plan view of one embodiment of the invention, partly broken away to expose the interior of the handle. 
           [0011]      FIGS. 2(   a )-( d ) are side elevation views of the prongs and end units of one embodiment of the invention. 
           [0012]      FIGS. 3(   a )-( d ) are side elevation views of the components of a heating prong of one embodiment of the invention. 
           [0013]      FIGS. 4(   a )-( b ) are elevation views of the components of an end unit of one embodiment of the invention. 
           [0014]      FIG. 5  is an elevation view of a mechanism for reducing the distance between the heating prongs of the hair iron. 
           [0015]      FIG. 6  is an exploded view of the embodiment shown in  FIG. 5 . 
           [0016]      FIG. 7  is an exploded view of the embodiment shown in  FIG. 1 . 
           [0017]      FIG. 8  is an elevation view of the embodiment shown in  FIG. 1 . 
           [0018]      FIG. 9  is a rear plan view of the embodiment shown in  FIG. 1 , partly broken away to illustrate interior features. 
           [0019]      FIG. 10  is a perspective view of the embodiment shown in  FIG. 1 . 
           [0020]      FIG. 11  is a front elevation view of one embodiment depicted in the closed, engaged mode of operation. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
         [0022]      FIG. 1  illustrates the preferred embodiment of the hair iron  1  in the overall shape of a hair pick, having a plurality of substantially parallel teeth  29 . A tooth may be a non-heating end unit  3  or a heating prong  2 . Heating prongs  2  can be provided between a pair of non-heating end units  3 . However, any number of heating prongs more than two may be utilized by the current invention. End units  3 , if present, may or may not be substantially parallel to the heating prongs  2 . 
         [0023]    In the embodiment depicted in  FIG. 1 , the teeth  29  are mounted within the body  31  of a handle  16  of the heating iron  1  and extend from the handle  16  in a manner substantially parallel to one another. The hair iron  1  further comprises a trigger  19  which when actuated or depressed by a user activates a drive mechanism  32  that reduces the distance between at least two prongs  2  while maintaining the prongs  2  in a position substantially parallel to one another. The hair iron is thereby moved into an engaged, closed arrangement. In the disengaged open arrangement, the invention possesses the overall general shape of a pressing comb. The heating prongs  2  can maintain a position substantially parallel to a longitudinal or latitudinal midline of the handle. In one embodiment, depressing the trigger  19  reduces the distance between the heating prongs  2  while maintaining the heating prongs  2  in an orientation substantially parallel to one another. In a further embodiment, depressing the trigger may manipulate the end units  3  in a manner similarly to the prongs  2 . The trigger  19  may be fashioned in a variety of shapes and sizes. 
         [0024]    The hair iron  1  can further comprise a switch button  4  that can be actuated by a user to initiate an electric current through circuitry of the hair iron. The hair iron when actuated converts the electric current into thermal energy. The hair iron may further comprise a temperature dial  5  that can be turned, shifted or otherwise manipulated to vary the intensity of heating. The dial may offer a user the ability to select any heating intensity within a continuous range of temperatures, or the dial may delimit a specific number of discrete heating levels. In the scenario of a discrete number of heating levels, a user may for example, select high, medium, or low heat. Or, the user may select a heating level ranging from, for example, 1 to 25. The dial may be circular or any manner of switch that can vary the temperature of the hair iron. The dial may vary the temperature of the hair iron by, for example, controlling the current, or by any other means of controlling the degree of heating known in the art. A user would operate the hair iron while gripping the handle  16 . 
         [0025]      FIGS. 2(   a )-( d ) provide an elevation view of the heating prongs  2  and end units  3  of one embodiment of the invention. Each heating prong  2 , as illustrated in  FIGS. 2(   b )-( c ) may further comprise a heating plate  7  that transfers thermal energy through its face  11  to hair. Each prong  2  may further comprise a thermally insulating guard  6 . The thermally insulating guard  6  may at least partially surround an outer portion of each prong  2  that would otherwise be likely to come into contact with a user&#39;s scalp. For instance, the edge  30  of each heating plate  7  may be partially surrounded by the thermally insulating guard  6 . Acting as a barrier, the thermally insulating guard  6  acts to reduce the incidence of accidentally touching and thereby burning one&#39;s scalp with a heating plate  7  of the heating prong  2 . 
         [0026]    The guard  6  may be attached to the heating plate  7  by any suitable means, for example, by screws or other methods of connection, placed through an outer attachment point  10  to an inner attachment member  9 . Alternatively, each guard  6  may be welded or otherwise directly connected to a heating plate  7 . Any number of attachment points may be utilized. Preferably, the attachment points are located in areas that during use do not come into close contact with the scalp. 
         [0027]    As illustrated in  FIGS. 2(   b )-( c ) the thermally insulating guards  6  may be separated from the heating plates  7  at a distance created by an air space  8 . The air space  8  is thermally insulating and allows the guard to remain cool while the heating plates  7  reach temperatures that can exceed 400° Fahrenheit. The width of the air space  8  between the guard and the heating plate is preferably about 1 mm to about 2 mm, but may range from 0 mm to approximately 5 mm. Air space  8  may be maintained, for example, by the inner attachment member  9  protruding from the guard  6  to prevent the plate  7  from contacting the guard  6 . The attachment member  9  may connect the guard  6  to the plate  7  and can be substantially non-thermally conducting. Additionally, air space  8  between the guard  6  and the heating plate  7  may be maintained through various other methods such as completely separating the guard  6  from the heating plate  7 . The attachment member  9  may be connected to either the guard  6 , the heating plate  7 , both the guard  6  and the heating plate  7 , or may be an integral part of either the guard  6  or the heating plate  7 . 
         [0028]    When the heating prongs  2  such as those depicted in  FIGS. 2(   b )- 2 ( c ) are mounted within a hair iron such as depicted in  FIG. 10 , the faces  11  of the heating plates  7  stand opposite one another so that locks of hair gathered between the heating prongs  3  may be heated. Also when mounted within a hair iron such as depicted in  FIG. 9 , the guards  6  may surround an outer edge  30  of the plates  7  that would otherwise be exposed to the outside of the hair iron. 
         [0029]      FIGS. 3(   a )- 3 ( d ) depict a plan view of possible components of a heating prong. An insulating guard  6  is illustrated in  FIG. 3(   a ), and a heating plate  7  is depicted in  FIG. 3(   b ). Each heating prong may also comprise a support  13  as illustrated in  FIG. 3(   c ) and a heating element  12  as depicted in  FIG. 3(   d ). 
         [0030]    As discussed in relation to  FIGS. 2(   b )-( c ), the thermally insulating guard depicted in  FIG. 3(   a ) may surround a portion of the heating plate  7 , which is separately depicted in  FIG. 3(   b ). The thermally insulating guard  6  may be made from heat resistant materials or materials possessing sufficiently light mass and low rates of thermal absorption sufficient such as phenolic plastic. The guard may be present in various shapes, including wedge-shapes. The insulating guard  6  may be made of multiple pieces joined together as illustrated in  FIG. 3(   a ) or may be made from one piece as illustrated in  FIGS. 2(   b )-( c ). 
         [0031]    A heating plate  7 , such as the plate depicted in  FIG. 3(   b ), may transfer thermal energy from the hair iron to a lock of hair. The heating plates  7  are preferably made out of ceramic, but the plates may be fabricated of any metallic, ceramic or stone material possessing a high rate of thermal conduction and a high retentive thermal mass sufficient to efficiently withstand and deliver heat and pressure to locks of hair compressed between the heating plates. Alternative embodiments include plates  7  made from jade, sapphire, etc. For example, a heating plate  7  may be made from a metal, such as aluminum, surrounded by a ceramic coating. The heating plates  7  may further be surfaced with non-stick coatings to reduce the likelihood that hair will stick to the heating plates. 
         [0032]    Each heating plate  7  may partially envelop a combination including a support  13 , as depicted in  FIG. 3(   c ), and a heating element  12  as depicted in  FIG. 3(   d ). The support serves to provide a surface to bear the weight of and brace the other components of the tooth  29 , and further serves to connect those components to the handle  16 . The heating element  12  may be connected to the support  13  by, for example, brackets or other means known in the art mounting the heating element to the support  13 . Alternatively, the heating element  12  may be welded, glued, or otherwise secured to the support  13 . As illustrated in  FIGS. 2(   a )-( d ), both the end units  3  and prongs  2  may comprise a support  13 . The support  13  may be made from several different types of materials ranging from plastics to metals. The support  13  may comprise guide holes  14  for mounting the support  13  within the handle  16 , as depicted in  FIG. 1 . The guide holes  14  optimally are spaced in a manner that allows the heating prongs  2  and optionally the end units  3  to remain substantially parallel when the hair iron  1  is engaged. The guide holes may be placed in several different locations to allow for maximum efficiency. 
         [0033]    As depicted in  FIG. 3(   d ), the heating element  12  may be a rope heater. Alternatively, the heating element may be any electrical resistant heater, a PTFC heater or a ceramic heater. Or, the heating element may be another type of heater known in the art. End portions  34  of the heating element  12  can connect to electrical wiring and circuitry within the handle  16  that provides an energy source to the heating elements  12 . The heating element  12  can transmit thermal energy to, for example, the heating plate  7 . 
         [0034]    In one embodiment not illustrated, the end units  3  may be heatable. If heatable, the end units may comprise heating plates  7 . The heating plates  7  of the end units  3 , may at least partially envelop a heating element  12  and support  13 . 
         [0035]      FIG. 4(   a )-( b ) illustrate the component part of an end unit. Like the prongs  2 , the end units  3  also comprise a support  13 . In the end units, the support  13  is secured to a cover  33  by screws, glue, or any other method of connecting two components known in the art. In one embodiment, the cover  33  may partially envelop the support  13 . In another embodiment, the support may secure to an outer face of the cover  33 . The cover  33  may be made from heat resistant materials or materials possessing sufficiently light mass and low rates of thermal absorption sufficient such as phenolic plastic. 
         [0036]      FIG. 5  is a plan partial view of one embodiment of the invention, particularly illustrating the drive mechanism  32  that can reduce the distance between the teeth  29 , including both the prongs  2  and end units  3 , while the teeth  29  remain substantially parallel to one another. In an alternative embodiment the drive mechanism  32  may only affect the prongs  2 . The drive mechanism may be mechanical, electrical, solenoid, hydraulic, pneumatic or any other type of drive mechanism known in the art. 
         [0037]    In a first mode of operation, the drive mechanism can move at least one of the teeth  29  so as to reduce the distance between at least two of the teeth to apply heat and pressure to hair between the teeth. The first mode of operation shifts the hair iron from an open, disengaged arrangement, to a closed, engaged arrangement. During a second mode of operation the drive mechanism  32  can move at least one of the teeth  29  so as to increase the distance between at least two of the teeth to release the hair from between the teeth. During both the first and second modes of operation, at least all prongs remain substantially parallel. In the embodiment illustrated in  FIG. 5 , all teeth  29  including all prongs  2  and the end units  3  remain substantially parallel during both the first and second modes of operation. 
         [0038]    Alternatively, in the embodiment not illustrated in which the drive mechanism  32  moves the heating prongs  2  but not the end units  3 , in a first mode of operation, the drive mechanism can move at least one of the heating prongs  2  so as to reduce the distance between at least two of the prongs to apply heat and pressure to hair between the prongs. During a second mode of operation the drive mechanism  32  can move at least one of the prongs  2  so as to increase the distance between at least two of the prongs to release the hair from between the prongs. During both the first and second modes of operation, all prongs can remain parallel. 
         [0039]    The components of one embodiment of the drive mechanism  32  are shown in the exploded view in  FIG. 6 . The drive mechanism may include a boot that serves to block water and other contaminants from entering the body  31  of the device&#39;s handle  16 , as illustrated in  FIG. 1 . The boot can be manufactured from a compressible material such as rubber, so that the boot serves its function of blocking contaminants from entering the body  31  of the device&#39;s handle  16  when the collapsible mechanism  32  is actuated in a first or second mode of operation and when the device is in either an open or a closed arrangement. Although other constructions are possible, the drive mechanism  32  may include a boot  15  having slots  28  through which the supports  13  may be inserted. The boot  15  is mounted within the handle  16 , as shown in  FIG. 1 . Each slot  28  in the boot grips a circumference of each support  13 . One support  13  of either an end unit  3  or prong  2  passes through each slot  28 . The drive mechanism may further comprise a bias to maintain the hair iron in an open, disengaged arrangement. The bias may be created, by for example, a spring  17 , although the bias may be created by any other means known in the art. 
         [0040]    End units  3  may be absent. In such an embodiment, the outermost pair of teeth is heatable, unlike in the embodiment comprising end units  3 . Such an embodiment might include a plurality of substantially parallel heating prongs  2  where an outer portion of each prongs is surrounded by an insulating guard  6  to prevent contact with the skin of a user. The drive mechanism  32  in such an embodiment would operate in a first and second mode as described above. During the first and second modes of operation, all the heating prongs can remain substantially parallel to one another. 
         [0041]    In one embodiment depicted by the exploded view of  FIG. 6  in conjunction with the plan view of  FIG. 1 , the supports  13  remain substantially parallel to one another by being gripped by the boot  15  and by being slideably mounted on the guides  27 . The guides secure supports  13  within the handle and allow movement of the prongs  2  and optionally the end units  3 . The material used for the guides may include plastics or metals. The guides  27  can be positioned through the guide holes  14  of supports  13 , as illustrated in  FIG. 2 . The guides may further be connected to the handle  16 , for example by inserting the guides into female protrusions  26  on the handle, as displayed in  FIG. 1 . Alternatively, the guides may be integral components of the handle  16 . 
         [0042]    The spring  17  wraps around the guides  27  and between the supports  13 . A pusher  18  is positioned against at least one tooth  29 , where, as set forth in relation to  FIG. 1 , a tooth  29  is either a prong  2  or an end unit  3 . The tooth  29  most distal to the pusher may be slideably secured on the guides as illustrated or fixedly mounted. The drive mechanism  32  may reduce the distance between teeth by moving teeth in one common direction, for example from right to left, as the drive mechanism  32  illustrated in  FIGS. 5 and 6  would operate. The teeth could also be moved, for example, in the common direction of left to right. In the preferred embodiment, the pusher  18  applies force to the spring  17 , which compresses the teeth  29  together from right to left. Hence, first a tooth proximal to the pusher is moved from right to left, then the tooth second-most proximal to the pusher is moved from right to left, until the degree of compression is achieved. The compression is ultimately stopped at least by an obstruction to the leftmost tooth. 
         [0043]    Alternatively, the drive mechanism  32  may move the hair iron into a closed, engaged state by moving at least two prongs together by a suitable mechanism in opposing directions, such that the outermost pair of teeth are first compressed toward a center longitudinal line, then the second-most outer pair of teeth are compressed toward the center longitudinal line, until the desired degreed of compression is achieved. If the drive mechanism moves teeth together in opposing directions toward a center longitudinal line, then the teeth may be slidably secured, a center tooth may be fixedly secured, or the teeth may be connected to the drive mechanism by another method known in the art. 
         [0044]      FIG. 7  is an exploded plan view of the hair iron  1 . The hair iron  1  may further comprise a trigger  19  connected to the pusher  18 . For instance, the trigger  19  may be connected to the pusher  18  by a compression spring  20 . For instance, the compression spring  20  may be secured to the pusher  18  around its circumference as it passes through an attachment hole in the pusher  18 . The spring may be connected to the pusher  18  at the attachment hole by glue, welding, or some other means of attachment known in the art. Alternatively, the spring  20  may be split into two separate pieces, each of which is welded, glued, or otherwise connected to the pusher. In another embodiment, the spring  20  may wrap around the pusher  18 . 
         [0045]    The hair iron  1  may further comprise a printed circuit board (PCB)  21  that serves to mechanically support and electrically connect electrical components of the hair iron  1 . The electrical components may include, for example, the temperature dial  5 , which serves to vary the temperature of the hair iron  1 . The temperature dial  5  and PCB  21  may further connect to a switch  22  that controls the temperature dial  5 . The PCB  21  may further be connected to a second switch  23  is directly connected to the button  4 . The hair iron  1  can be turned on so that the heating elements  12  may be heated by pressing, shifting, or manipulating the switch button  4 . The hair iron  1  may further comprise an indicator, such as an LED  24 , that indicates the operational state of the device. 
         [0046]    The heating elements  12  may be electrically heated, and the heating may be regulated by the PCB  21 . The heating elements  12  may be connected by a wiring harness, which may be connected to the PCB  21 . The heating elements  12  may further be connected to grounding safety circuitry that ultimately exits the handle  16  as an electrical cord  25 . The electrical cord may be fitted with a plug that is adapted to mate with standard power supply outlets. The electrical cord  25  may be either permanent or removable, and the hair iron  1  may further include a rechargeable battery. The cord  25  may be for example, a 6-foot long cord having a male pin fitting at the end opposite the plug, such that the male pin can connect with a female receiver on the hair iron. Alternatively to electrically powering the hair iron, thermal energy may be delivered to the heating plates  7  by submersing the prongs  2  in a hot liquid medium, such as hot water or hot oil. 
         [0047]      FIG. 8  provides an elevation view of the hair iron  1 . The handle  16  possesses sufficient dimensionality and material properties to withstand hand-forced stresses without bending or breaking. The teeth  29  extend in a direction substantially parallel to a longitudinal midline of the handle. Each prong  2  comprises a thermally insulating guard  6  around its outer portion. 
         [0048]      FIG. 9  is a rear plan view of the embodiment shown in  FIG. 1 , partly broken away to illustrate interior features. The hair iron is illustrated in the open, disengaged mode. To operate the hair iron, a user would press or shift the switch button so that the heating prongs could be heated. The user could also adjust the temperature dial  5  to select a desired degree of heating. Then, a user could collect locks of hair between the teeth  29 . By pressing the trigger  19 , the user could reduce the distance between the teeth so that heat and pressure would be applied to the locks of hair. 
         [0049]      FIG. 10  is a perspective view of the embodiment shown in  FIG. 1  illustrating the exterior features of the hair iron. The end units  3  comprise a cover  33  on their exterior. The prongs  2  set between the end units  2 . The prongs  2  comprise thermally insulating guards  6  around a portion of their outer perimeter. A user of the hair iron would collect hair between the teeth  29 , and heat would be applied to the hair through the faces  11  of the heating plates  7 . 
         [0050]      FIG. 11  displays an engaged, closed mode of one embodiment of the flat iron in operation. When the switch button  4  is shifted to turn the hair iron on, and when the trigger  19  is engaged, the plurality of “pressing comb” type prongs  3  act together like a multitude of miniature “flat irons” to apply heat and pressure to hair gathered between the teeth  29 . 
         [0051]    While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.