Patent Document

This application claims the benefit of Provisional application Ser. No. 60/210,493, filed Jun. 9, 2000. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a hand held, motorized depilatory device for removing unwanted skin hair, and more particularly, to a revolutionary concept and mechanically correct design to pluck out skin hair, utilizing a novel mechanism to spirally align coupled-tweezer elements. 
     BACKGROUND OF THE INVENTION 
     The prior art of motor-powered depilatory devices for removing skin hair is based on a well-known concept disclosed in a patent covering an earlier mechanical device, Swiss Patent 268,696 to Fischer. There, a helical spring is arched, to provide spaces between loops of its convex side, and the spring is placed on the skin, under slight pressure, and rolled, in the direction of hair growth. The rolling motion of the helical spring causes hairs, which become trapped in the spaces, between the coil loops, on the convex side, to be plucked, when these spaces close, on the coil spring concave side. 
     U.S. Pat. No. 4,524,772 to Daar, et. al., discloses an arched, helical spring, which is provided with high speed, rotational motion via motor-driven couplings, connected at its ends. The contact between the helical spring wire and individual hairs is essentially point-like. A hair that is caught between the closed spring loops may be released before the plucking operation has been completed, which results in inefficient plucking and unnecessary pain. 
     Once a hair becomes trapped between closed helical spring loops, continued application of rotational force causes the spring to “wind up”, since it is composed of flexible wire material, yet the hair is still in place. As the spring continues to “wind”, the pulling tension applied to the hair increases until the necessary force is developed for plucking. Because a finite interval is required for this force to be developed, the user is subjected to an increased pain level. 
     The helical spring may break during use, due to the continuous bending stresses applied to it, creating a hazard to the user, as the spring is in direct contact with the skin. 
     In addition, a transverse deflection of hairs takes place, due to lateral movement of the spaces between the helical spring loops, which rotate in spiral fashion. Therefore, shorter hairs tend to escape the traps, created by the helical spring loops. 
     In U.S. Pat. No. 4,575,902 to Alazet, there is disclosed a depilatory device, comprising a series of adjacent, closely-spaced hair-plucking discs, driven by an electric motor, housed within a casing. The discs are periodically deformed during their rotation, such that adjacent ones, thereof, are pressed together to pluck hairs, which may have become trapped between them, when the unit is passed over the skin. When the discs are pressed together, the external hair-traps, thus formed, capture mainly hairs located in the center of the device&#39;s rotational path. The short hairs, located on the peripheries of the rotational path, are not trapped and consequently, not plucked. 
     In U.S. Pat. No. 4,575,902 to Alazet; U.S. Pat. No. 5,041,123 to Oliveau, and U.S. Pat. No. 4,960,422 to Demeester, simultaneous closing of blades is complicated and extremely difficult to ensure, while maintaining a uniform gripping force in all hair-traps. These patents describe devices, in which, parallel-positioned plucking blades or disks are fixed, relative to the rod, which carries them. Typically, cam driven motion of the rods causes the blades to close one against the other. On application of force, sufficient gripping force will be attained by some of the blades, while other blades will not be subjected to sufficient force and will remain open. 
     The difference in plucking-blade response to a given mechanical force is primarily a result of non-uniformity in the production of the unit elements. As a certain level of non-uniformity accompanies all production, correct and efficient performance requires finding a method to decrease, or preferably, eliminate the detrimental effects of non-uniform production. 
     In order for the blades to close, further force must be exerted, which causes excessive stress on the blades, which closed first. Excessive stress on the blades typically causes hair to be cut instead of plucked. In addition, a certain percentage of plucking attempts is unsuccessful. Each time hairs are pulled, without plucking the hairs, the result is increased pain, increased energy consumption, (which is particularly significant in the case of battery-operated devices), increased noise and excessive wear and tear of parts. 
     Therefore, it would be desirable to provide a superior power-driven depilatory device, which provides a drastic improvement in the ratio of plucked to cut hairs, while minimizing pain associated with the interval between grasping and plucking of individual hairs. 
     It would also be desirable to provide a depilatory device, which would reduce noise, and therefore be less frightening to the user. 
     Furthermore, in the prior art, the depilatory devices were designed, so that to be effective, the user had to hold the device substantially perpendicular to the skin surface, at many times, a most awkward position to work in. 
     Therefore, it would also be desirable to provide a depilatory device, whose design allows the user to efficiently utilize the device at additional contact angles with the skin surface. This would allow the user to easily maneuver the device, so as to remove hair efficiently, in hard-to-get-to areas, such as the back of the knee joint area. In addition, such a design would also allow the user to easily view the area to be depilated, which was most difficult to do in prior art devices. 
     Additionally, it would be desirable to provide a depilatory device, whose mechanically correct design will lead to an efficient distribution of the applied force and thereby reduce excessive wear of parts and improve the plucking efficiency. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is a principal object of the present invention to overcome the above-mentioned disadvantages and provide a hand-held, motorized depilatory device for removing unwanted skin hair, utilizing a mechanically correct design employing a novel mechanism to spirally align coupled-tweezer elements. 
     In accordance with a preferred embodiment of the present invention, there is provided a motor-powered depilatory device comprising: 
     a manually-held housing; 
     motor means disposed in said housing; and 
     a hair-plucking assembly, exposed through an opening in said housing, and coupled to said motor means, said hair-plucking assembly containing a right hand actuator element and a left hand actuator element, identical in construction, each carrying opposing tweezer elements, which fit together in interleaved fashion, arranged to define hair-traps, 
     said hair-plucking assembly being rotatable about a central shaft and operable to close and open said hair-traps by a system of cams and springs. 
     Hair-traps are developed by a series of tweezer elements, mounted circumferentially on said hair-plucking assembly. Each of said actuator elements has a pair of carrier arms, containing slots, in which said tweezer elements are mounted. The actuator elements are arranged to provide slots for installation of a plurality rows of tweezer elements, arranged in a staggered, rather than tandem arrangement. 
     The actuator elements, in the preferred embodiment of the present invention, are made of plastic and are simply designed, and identical in construction, making them inexpensive to manufacture, via injection molding. 
     On each actuator element, adjacent to the carrier arms are cams, on which are positioned cam followers that are supported by cam follower holders. Two sets of cam followers are held, one at each end, formed by the actuator elements, and are prevented from rotating by an actuator spring. The actuator spring is held in place within a slit, in the body of the appliance, which prevents it from rotating with the hair-plucking assembly. The actuator spring exerts pressure on the ends of the central shaft, which is relayed to the cam follower holders, the cam followers, and through the cams to the actuator elements. 
     The actuator spring transfers gripping force to the tweezer elements, where gripping force is the specific force required to grip and pluck the hairs. Gripping force is required only at specific points in the operating cycle. During the remainder of the cycle, a retaining spring mounted on the shaft provides the force needed to re-open the hair-traps. 
     In operation, when the hair-plucking assembly receives rotational motion, the cam followers roll on the cams and when they reach a projection on the cam surface, the actuator elements are pushed one against the other, thereby causing the tweezer elements, of opposing actuator elements, to engage, forming hair-traps on all rows of tweezer elements, simultaneously. Thus, hairs are plucked out, during the rotational motion of the hair-plucking assembly. The cam followers continue rolling along the contour of the cams, eventually arriving at a depression in the cams. At that point, the retaining spring is free to return the actuator elements, as well as the tweezer elements situated on them, to their initial positions, thereby opening the hair-traps, allowing the plucked hair to be released. 
     Cams are located at each end of the hair-plucking assembly, and are arranged as a set in a circular arrangement, which effectively constitutes a continuous cam arrangement. In the preferred embodiment, a set of four cam followers, arranged perpendicular to each other, is positioned on each set of cams. This correct mechanical design allows the force applied by the actuator spring to be evenly distributed on all points of the cams of the actuator, surrounding the shaft. Thus, the force per point is smaller than in prior art devices, reducing the stress per point, which is an important factor in reducing accelerated wear of parts and excessive noise. 
     Each tweezer element comprises two wing segments and a central portion. In one of its embodiments, the tweezer element, in its central segment, has formed thereon protrusions. A tweezer element, when engaged, is able to rock slightly around the protrusions. This arrangement permits self-alignment of the tweezer element, thereby enabling uniform distribution of gripping force among all hair-traps. In another embodiment, instead of a protrusion on the tweezer element, a swivel ridge is formed on the wall of the slot, in which the tweezer element is mounted. 
     The assembly procedure of the hair-plucking assembly is quite simple and rapid. The tweezer elements are snapped into position easily, and held in place by a tongue, or other mechanical means, such as the hair-guide unit, utilized in one of the embodiments. 
     The tweezer elements are arranged around the hair-plucking assembly, in such a way, that the tips of each tweezer element can engage with the tips of each of two adjacent tweezer elements, so that the tweezer elements form a continuous spiral around the circumference of the assembly. The tweezer elements are able to rock slightly around said protrusions, and thereby align themselves relative to fixed points, provided by a fixed tweezer element. This novel mechanism ensures that all tweezer elements close simultaneously, developing an appropriate equal gripping force, despite inaccuracies in manufacture. 
     The inventive hair-plucking assembly insures all the hair-traps close simultaneously during a revolution of the hair-plucking assembly, with no excessive applied force being required. Quality of hair plucking is thereby improved, where quality of plucking is defined as the percentage of hairs plucked versus percentage of hairs cut. In prior art devices, excess applied force led to an increase in the number of hairs cut rather than plucked. 
     The staggered arrangement of tweezer elements contributes to a much more even treatment of the skin surface, and to an increase in the speed of removal of hairs from a given area, thus leading to reduced energy consumption per unit of time. 
     A further advantage of the present invention is the operation of the actuator elements by the continuity of the cams. The use of four cam followers per cam, eliminates the need to jump from one cam to another, as is the case in, other hair plucking appliances. This configuration decreases noise levels, reduces energy requirements and reduces wear and tear of the device. 
     Other features and advantages of the invention will become apparent from the drawings and the description contained herein below. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     For a better understanding of the invention, with regard to the embodiments described, reference is made to the accompanying drawings, in which like numbers designate corresponding elements or sections throughout, and in which: 
     FIG. 1 schematically illustrates a prior art hair plucking device disadvantage, in which only a portion of the hair-traps are closed, while other traps remain open; 
     FIG. 2 schematically illustrates a prior art hair plucking device situation where excess force is exerted in order to ensure closure of all the hair-traps; 
     FIG. 3 shows a perspective view of an exemplary embodiment of a hair-plucking assembly for use in a hair depilating device, constructed and operated in accordance with the principles of the present invention; 
     FIGS. 4 a-d  show a single actuator element, illustrating a tweezer element mounting method using a hair guide to hold them in place, while guiding the hairs; 
     FIG. 5 shows a perspective view of a preferred embodiment of the hair depilating device, using the hair-plucking assembly of FIG. 3; 
     FIG. 6 shows a perspective view of the hair plucking assembly of FIG. 5, without the housing; 
     FIG. 7 shows a side view of a preferred embodiment of the depilating device; 
     FIG. 8 displays a sectional view of the apparatus taken along the section line VIII—VIII of FIG. 7; 
     FIG. 9 shows a perspective exploded view of the device shown in FIG. 5; 
     FIG. 10 is a perspective view of a tweezer element; 
     FIG. 11 shows a perspective view of a segment of a carrier arm, showing the tweezer elements within the slots; 
     FIG. 12 is a side view of the segment of the carrier arm shown in FIG. 11; 
     FIG. 13 is a front view of the carrier arm of FIG. 11; 
     FIG. 14 is a sectional view of the segment of the carrier arm, taken along section line XIV—XIV of FIG. 13; 
     FIG. 15 is a top, sectional view of the segment of the carrier arm, taken along section line XV—XV of FIG. 13; 
     FIG. 16 is a top view of the segment of the carrier arm shown in FIG. 11; 
     FIG. 17 is a cross-sectional view of the segment of the carrier arm taken along section line XVII—XVII of FIG. 12; 
     FIG. 18 is a perspective view of the tweezer elements, when all the traps are closed, showing the arrangement as a spiral continuity; 
     FIG. 19 is an additional perspective view of the tweezer elements in closed hair-trap formation; 
     FIG. 20 is a view of the hair-plucking assembly, cut and opened out along its longitudinal axis, with the tweezer elements in open hair-trap formation; 
     FIG. 21 is a view of the arrangement of FIG. 20, with the tweezer elements in closed hair-trap formation; 
     FIG. 22 is a schematic representation of the tweezer elements performing self-alignment; 
     FIG. 23 is a schematic representation of the tweezer elements after self-alignment, and schematically displays the spiral, staggered arrangement of the tweezer elements; 
     FIGS. 24 a-b  are top and cross-sectional views of a section of the carrier arm, showing an embodiment in which the tweezer element rocks on a swivel ridge that protrudes into the gap between the tweezer element and the slot wall; 
     FIG. 25 is a perspective exploded view of an actuator element in an embodiment of the device, showing the tweezer elements mechanically locked in the slots via pins that pass through them, over the actuator element length, 
     FIG. 26 schematically illustrates the additional angles at which the user may hold the device while depilating, to facilitate the depilating process; 
     FIG. 27 schematically illustrates use of the device against a hard to reach skin surface, without requiring a change in the angle at which the device is applied; 
     FIG. 28 shows an alternative embodiment of the hair-plucking assembly, featuring an annular grouping of tweezer elements; 
     FIG. 29 is a perspective view of the tweezer elements, when all the traps are open, showing the arrangement of the annular grouping; 
     FIG. 30 is a schematic representation of the tweezer elements after self-alignment, and schematically displays the annular grouping of the tweezer elements; 
     FIG. 31 is a view of the hair-plucking assembly of FIG. 28, cut and opened out along its longitudinal axis, with the tweezer elements in open hair-trap formation; and 
     FIG. 32 is a view of the arrangement of FIG. 31 with the tweezer elements in closed hair-trap formation. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to prior art FIGS. 1 and 2, there are shown enlarged views of plucking elements  30 , each pivotally mounted at one end along the axis of a mounting element  32  to define hair-traps  34 . In such an arrangement, even distribution of gripping force is extremely difficult to achieve primarily due to the cumulative effect of production non-uniformities. 
     As shown in FIG. 1, on application of pressure by an actuator  36 , sufficient gripping force will be attained by some of the plucking elements  30 , and their corresponding hair-traps  34  will close, while a certain percentage of open hair-traps  34  will not receive sufficient gripping force, and therefore, will remain open. As seen in FIG. 2, in order for the hair-traps of all the plucking elements  30  to close, further pressure must be exerted. Some plucking elements become distorted, and this causes excessive wear, excessive noise, excessive energy consumption, and cuts the hair instead of plucking it. The present invention provides a solution to this problem. 
     Referring to FIGS. 3-4, there is shown a perspective view of an exemplary embodiment of a hair-plucking assembly  35 , for use in a hair depilating device  36  (FIG.  5 ), constructed and operated in accordance with the principles of the present invention, the purpose of which is to trap unwanted hairs in hair-traps  40  and to pluck them out from the root. Hair-plucking assembly  35  comprises two identical, opposing actuator elements, a right-hand actuator element  42  and a left-hand actuator element  44  (FIG. 4 a ), which fit together between circular endplates  46 . When assembled, hair-plucking assembly  35  has a substantially circular cross-section. 
     Hair-plucking assembly  35  is driven by a motion conversion mechanism (FIG. 6) that translates the rotational motion of the hair plucking assembly into reciprocating motion of endplates  46  along the longitudinal axis of hair-plucking assembly  35 , as indicated by motion arrows X and Y. The detailed components of the mechanism are shown in FIG.  8 . 
     In FIGS. 4 a-b , there are shown perspective exploded views of the left-hand actuator element  44 . In respective actuator elements  42  (FIG. 8) and  44  there are a pair of carrier arms  47 ,  48 . There are formed in carrier arms  47 ,  48  spaced-apart slots  50 , each having seated therein a tweezer element  52 , the wings of which are exposed on the periphery of each carrier arm  47 ,  48 . Each tweezer element  52  is shaped as a central portion  54 , with peripheral wing sections  56 ,  58  formed on opposing sides of central portion  54 , one wing slightly offset forward of central portion  54  and one behind it, as further illustrated in FIG.  10 . 
     Slots  50  are formed transverse to the longitudinal axis of the hair plucking assembly  35 , and tweezer elements  52  are each formed with a pivoting point, which allows longitudinal rocking motion of tweezer elements  52  with respect to the longitudinal axis, within the slot. This enables self-alignment of the tweezer elements  52 , as further illustrated in FIG.  15 . 
     Slots  50  on actuator element  48  and slots  50  on actuator element  44  are arranged, such that the wings  56 ,  58  of the tweezer elements  52 , mounted on one actuator element are interleaved with the wings of tweezer elements  52  on the other. Thus, spaces are developed between opposing wings of interleaved tweezer elements  52 , these spaces being defined as hair-traps  40 . Also shown is hair-guide retaining unit  60 , which fits over tweezer elements  52  and holds them in place, while directing the hairs that escape one hair-trap into the path of the next hair-trap, and so forth. Hair-guide retaining unit  60  also completes the cylindrical contour of the hair-plucking assembly  35 . 
     FIG. 4 c  is a side view of the left-hand actuator element  44  of FIG. 4 b . FIG. 4 d  is a cross-sectional view taken along section line d—d, showing hair guide  60  seated over tweezer element  52 , to hold it in place, by snap-in clips  59  which engage grooves  61  formed on the carrier arms  47 ,  48 . 
     In FIG. 5, there is shown a perspective view of the exemplary embodiment of hair depilating device  36 , which comprises a casing  64 , in which there is mounted a hair-plucking assembly  35 , as shown in FIGS. 3-4. The hair-plucking assembly  35  comes in contact with the skin via an opening in the casing  64 . The casing is connected on one side to a cover  66 . 
     As can be seen in the perspective view of FIG. 6, the hair-plucking assembly  35  is driven by an electric motor  68  via a reduction gear  70  rotating on shaft  71 . The hair-plucking assembly  35  comprises a right-hand actuator element  42  and a left-hand actuator element  44 , which fit together between circular endplates  46 , each one identical to the other, and formed integrally with a respective actuator element. Hair-plucking assembly  35  also comprises cam follower holders  72 , an actuating spring  74 , and a split central shaft  76   a-b.  The hair-plucking assembly  35  is designed to have mounted thereon a series of tweezer elements  52 . 
     FIG. 7 shows a side view of the exemplary embodiment of depilating device  36 . 
     FIGS. 8 and 9 show further construction details of the hair-plucking assembly  35 . 
     FIG. 8 displays a sectional view of the device  36 , taken along section line VIII—VIII of FIG.  7 . 
     In each actuator element  42  and  44 , there is a hole,  78  and  80  respectively, which serves as a bearing to the central shaft  76   a-b.  On each actuator element, there are integrally formed on endplates  46  a set of cams,  82  and  84 , on which are positioned cam followers  86 , which are supported by cam follower holders  72 . Two sets of identical cam followers  86  are held, one at each end of hair-plucking assembly  35 , formed by the actuator elements  42 ,  44 . The cam follower holders  72  are prevented from rotating by an actuator spring  74 . 
     The actuator spring  74  is held in place within a slit  88  (shown in FIG.  9 ), in the body of the appliance, which prevents the actuator spring from rotating with the hair-plucking assembly  35 . There is a niche  75  at each end of the actuator spring  74 . As the heads  77  of the central shaft  76   a-b  are spherical, they fit smugly into said niches, allowing for excellent self-alignment of the assembly. 
     The actuator spring  74  presses inwards at the heads of the central shaft  76   a-b , which applies pressure on the cam follower holders  72 , which, in turn, transfer the pressure via the mechanism of the cam followers  86 , and the cams  82  and  84 , to the actuator elements  42  and  44 . 
     The central shaft  76   a-b  comprises two identical halves of fixed length, mounted end to end, whose purpose is to provide pretensioning of the actuator spring  74 , until the spring is brought into operation. This occurs when the cam followers  86  reach the raised portion on the surfaces of the cams  92  and  84 . The purpose of the actuator spring  74  is to transfer gripping force to the tweezer elements  52 . Gripping force is the specific force required to grip the hairs and pull them out by the root. 
     The shaft  76   a-b  is important in regulating the resistance to rotation of hair-plucking assembly  35 . If there were no shaft, the full magnitude of inwardly-directed force provided by actuator spring  74  would be applied as soon as the assembly  35  began its rotation. This would result in increased resistance to rotational motion and would necessitate a higher energy input by motor  68  to overcome it. There would also be much more noise and greater wear. 
     The gripping force is only required during a portion of the operating cycle and is only effective during this period. During the remainder of the operating cycle, the full force of the actuator spring  74  is not required, and as described previously, central shaft  76   a-b  maintains pretensioning of actuator spring  74 . Retaining spring  85  is provided between sections of the central shaft  76   a-b,  to hold the hair-traps  40  open, by forcing the actuator elements  42  and  44  apart, until the next time they are driven together by cams  82 ,  84 . 
     FIG. 9 presents a perspective exploded view of the device shown in FIG.  5 . The hair-plucking assembly  35  is contained within a depression  90 , formed in one end of casing  64 , and cover  66 . Cover  66  is located on the opposite end of the casing. The hair-plucking assembly  35  comprises two identically constructed actuator elements,  42  and  44 , each of which contains a pair of carrier arms  47  and  48 . Each carrier arm  47 ,  48  is formed with slots  50 , which hold the tweezer elements  52 . 
     Each carrier arm has one fixed end blade  92 , which does not move from its position and is secured in place by positioning pin  93 , or by other mechanical means. Central shaft  76   a-b  passes through a hole  78 ,  80  formed in each actuator element. The grooves  94 , formed on carrier arms  47 ,  48  around the tweezer element slots  50 , function to guide the hairs into the hair-traps  40 , which are created at the ends of the tweezer elements. 
     Cams  82 ,  84  are formed on each end of the hair-plucking assembly  35 , comprised of the interleaving actuator elements  42 ,  44 . The cams  82 ,  84  are arranged as a set of four, in a circular arrangement, which effectively creates a continuous cam arrangement. A set of four cam followers  86 , arranged perpendicular to each other, is positioned on each set of cams. The cam followers  86  are mounted so as to be free to rotate in slots  101  of cam follower holders  72 , which are supported on shaft  76 . The cam follower holders  72  are prevented from rotating by the actuator spring  74 , which is situated in slots  102  of the cam follower holders  72 . 
     In operation, the hair-plucking assembly  35  receives rotational motion from the motor  68 , via the reduction gear  70  (see FIG.  6 ). The cam followers  86  roll on the cams  82 ,  84 , and when they reach the raised portion of the cam surface, as shown in FIG. 21, actuator element  42  and  44  are pushed one against the other, thereby causing the plucking elements  52 , of the opposing actuator elements, to engage, thereby forming hair-traps  40 . Thus, hairs are plucked out during the rotational motion of the hair-plucking assembly  35 . As shown in FIG. 20, the cam followers  86  continue following the contour of cams  82 ,  84 , eventually arriving at a depression on the cam surface. The retaining spring  85  then causes the actuator elements  42  and  44 , together with the tweezer elements  52  mounted on them, to return to their normally open positions, thereby opening the hair-traps  40  and allowing the plucked hair to be released. The process repeats for subsequent rotations of hair-plucking assembly  35 . 
     FIG. 10 is a perspective view of a tweezer element  52 . Each tweezer element  52  comprises two wing segments  56 ,  58  and a central portion  54 . In this embodiment, the plucking element  52  in its central segment, has formed thereon protrusions  121 , which enables the tweezer element to rock slightly about the protrusions, in the directions shown by the arrows in FIG.  15 . The purpose of this design is to permit self-alignment of the tweezer elements, thereby contributing to uniform distribution of gripping force among the hair-traps  40 . The tweezer elements  52  are snapped into position in slots  50  and held in place by a tongue  122  or by other mechanical means. 
     FIG. 11 shows a perspective view of a segment of a carrier arm  47  of actuator element  42 , showing the tweezer elements  52  mounted within the slots  50 . The positioning pin  93 , or other mechanical means, holds the fixed tweezer element  92  in place. 
     FIG. 12 shows a side view of the segment of carrier arm  47 , seen in FIG. 11, showing the tweezer elements  52  within the slots  50  and the adjacent grooves  94  which guide the hairs into the traps  40 . 
     FIG. 13 is a front view of the segment of carrier arm  47 , seen in FIG.  11 . 
     FIG. 14 shows a sectional view of carrier arm  47 , taken along section line XIV—XIV of FIG. 13, in which there is shown tweezer element  52  and its swivel protrusion  121 . The tweezer element is held in place by tongue  122 . Also shown is a fixed tweezer element  92 , which is held in place by positioning pin  93 . 
     FIG. 15 is a top, sectional view of carrier arm  47 , taken along section line XV—XV of FIG. 13, in which there is shown the mounting of tweezer elements  52 , arranged to rock back and forth on carrier arm  47 . Also shown is the fixed tweezer element  92 , which is held in place by positioning pin  93 , slots  50  and the hair-guide grooves  94 . 
     FIG. 16 is a top view of the segment of the carrier arm  47  shown in FIG.  11 . FIGS. 15-16 assist the viewer in visualizing the self-alignment possibilities that this device-design allows. 
     FIG. 17 is a cross-sectional view of a segment of carrier arm  47  taken along section line XVII—XVII of FIG.  12 . 
     FIG. 18 is a perspective view of the tweezer elements  52 , when all the hair-traps  40  are closed, showing the arrangement as a spiral continuity  124 . 
     FIG. 19 is an additional perspective view of the tweezer elements  52  in closed hair-trap formation. This view better illustrates protrusions  121 , providing swivel points enabling efficient gripping force distribution among tweezer elements  52 , which are arranged as shown around central shaft  76   a-b  (shaft not shown). 
     FIGS. 20 and 21 show how the hair-plucking assembly  35  would appear if cut along its longitudinal axis and opened out. This illustration enables an appreciation of the mechanically correct and efficient staggered hair-trap arrangement relative to the surface being depilated. 
     In FIG. 20, the cam followers  86  have reached the depressions in the surface of the cams  82 ,  84 , and consequently, the hair-traps  40  are open. The continuous cam arrangement can be clearly seen in these figures. The cam followers  86  roll smoothly from cam to cam in a continuous circle, without the need to jump from cam to cam, as occurs in prior art devices. The equalized stress distribution on the cams and cam followers is also apparent, and this reduces wear and tear, noise generation, and energy consumption. 
     FIG. 21 shows the arrangement of FIG. 20, with the cam followers  86  located on the raised portions of the cams  82 ,  84 , causing the tweezer elements  52 , of opposing actuator elements  42  and  44 , to close against each other, thereby, closing hair-traps  40 . 
     FIG. 22 is a schematic representation of the tweezer elements performing self-alignment. FIG. 23 shows how tweezer elements  52  are arranged around the cylindrical hair-plucking assembly  35 , so that the tips of each tweezer element  52  can engage with the tips of each of two adjacent tweezer elements. Thus, the tweezer elements  52  create a continuous spiral  124  around the circumference of the hair-plucking assembly  35 , and guarantee self-alignment all along the spiral. 
     In FIG. 22, the misalignment of the tweezer elements is exaggerated for the purpose of demonstration. The tweezer elements  52  are able to rock slightly around a ridge  130 , and thus align themselves relative to fixed points, provided by the fixed tweezer elements  92 . This design ensures that all tweezer elements  52  close simultaneously in response to an appropriate gripping force, and even compensates for manufacturing inaccuracies, as illustrated in FIGS. 22 and 23. In FIG. 23, there are also shown schematically the elements  52  spiraling along the circumference of assembly  35 . 
     In FIGS. 24 a-b,  there are shown top and cross-sectional views of a segment of carrier arm  47 . In this embodiment, the wall of slot  50  has formed thereon a ridge  130 , to maintain tweezer element  52  spaced apart from the wall. The tweezer element  52  is able to rock slightly about this ridge protrusion. The purpose of this design is to permit self-alignment of the tweezer elements, thereby contributing to uniform distribution of gripping force among the hair-traps  40 . 
     In FIG. 25, there is shown a perspective exploded view of an actuator element  42 , showing an alternative mechanical locking arrangement of tweezer elements  52  in the slots, using pins  132  (FIG. 24 b ) that pass through them over the actuator length. 
     In FIG. 26, there is shown a schematic representation of four depilating zones on the invention&#39;s hair-plucking assembly periphery. In accordance with the present invention, four depilating rows are employed on the periphery of hair plucking assembly  35 , and up to three zones may be exposed simultaneously, thereby facilitating depilation in hard-to-reach areas. 
     In FIG. 27, there is shown a schematic representation of the device  36  depilating a hard-to-reach area behind the knee joint. The device may be held at one particular angle, without requiring adjustment on passing between portions of the leg. 
     FIG. 28 shows an alternative embodiment of the hair-plucking assembly  35 , featuring an annular grouping of tweezer elements  52 . 
     FIG. 29 is a perspective view of the tweezer elements  52 , when all the hair-traps  40  are open, showing the arrangement the annular grouping. 
     FIG. 30 is a schematic representation of the tweezer elements  52  after self-alignment, and schematically displays the annular grouping of the tweezer elements. FIG. 30 shows how the tweezer elements are arranged around the cylindrical hair-plucking assembly, so that the tips of each tweezer element  52  can engage with the tips of each of two adjacent tweezer elements. In this embodiment, the tweezer elements are arranged in four discrete annular groupings. Within each grouping, self-alignment is performed. 
     FIG. 31 is a view of the hair-plucking assembly of FIG. 28, cut and opened out along its longitudinal axis, with tweezer elements  52  in open hair-trap  40  formation. 
     FIG. 32 is a view of the arrangement of FIG. 31 with the tweezer elements  52  in closed hairtrap  40  formation. 
     Having described the invention with regard to a certain specific embodiment, it is to be understood that the description is not meant as a limitation since further modifications may now suggest themselves to those skilled in he art, and it is intended to cover such modifications, as fall within the scope of the appended claims.

Technology Category: 1