Abstract:
The present invention pertains to a versatile fastener essentially comprising at least two flat areas formed on a cutting part, and an accommodating area disposed between any two of the flat areas. Wherein, at least two cutting faces are convergent to form the accommodating area, a first and a second cutting edges are respectively formed at a connection between each cutting face and flat area. In operation, the flat areas facilitate the first and the second cutting edges to promote a stable balance with the object, thereby allowing the debris to be swiftly guided out of the accommodating areas. Consequently, it is difficult to crack the object while imparting forces thereon so as to lower the screwing resistance and the fastening torque as well as preferably increase the combining efficiency.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a fastener, in particular to a versatile fastener that provides a preferable stability in time of fastening and favorably decreases the screwing torque as well as the resistance. 
         [0003]    2. Description of the Related Art 
         [0004]    A conventional screw  1  shown in  FIG. 1  generally comprises a shank  11 , a head portion  12  disposed at one end of the shank  11 , and a plurality of threads  13  spirally disposed on the shank  11 . Wherein, a free end  14  is formed at the other end of the shank  11 . The free end  14  includes a guiding area  141  defined on the surface thereof as well as extensively formed in the connection with the threads  13 , and a cutting edge  142  defined on a congregation formed by the guiding area  141 , the free end  14 , and the threads  13 . In applying the screw  1  for fastening, the free end  14  of the screw  1  is propped against an object  2 ; thence, the free end  14  leads the entire screw  1  to gradually screw into the object  2 . Herein, the cutting edge  142  drills and chips the object  2 , and the guiding area  141  guides the debris generated from the drilling. Accordingly, the screw  1  achieves the fastening and fixing function. 
         [0005]    However, in practice, the conventional screw  1  merely utilizes the guiding area  141  and the cutting edge  142  formed on the free end  14  to implement the cutting and the debris guidance. Wherein, an included angle formed on the guiding area  141  is rather small; thus, the accommodating area accordingly defined thereby is relatively confined. As a result, the debris generated in time of screwing is readily retained in the guiding area  141 , hence incurring a poor guiding effect. Moreover, such screw  1  merely renders the threads  13  provide multiple supporting points to engage with the object  2 . Therefore, if a rotating force is continuously executed on the screw  1 , the debris will be adversely compressed in view of the unfavorable guiding effect; additionally, the object  2  will readily sway because of the insufficient supporting force. As a result, the object  2  readily splits due to the overlarge screwing torque. Whereby, the screw  1  also fails to provide a speedy screwing and influences the screwing effect. 
         [0006]    Accordingly, another conventional screw  3  is disclosed for removing the disadvantages of the conventional screw  1 . Referring to  FIG. 2 , the screw  3  comprises a shank  31 , a head portion  32 , and a plurality of threaded portions  33  spirally disposed on the shank  31 . Wherein, a free end  34  is formed at one end of the shank  31 , and a blank area  35  is formed between the threaded portion  33  and the free end  34 . Further, a plurality of protruding ribs  351  are formed on the blank area  35 . In screwing, the free end  34  is propped against an object  4 , and thence the screw  3  is gradually screwed into the object  4  via a screwing force. By means of the protruding ribs  351  providing a reaming effect on the object  4 , the succeeding screw  3  could achieve a swift drilling. Thence, a fastening and fixing effect is accomplished. 
         [0007]    However, while the object  4  is reamed by the protruding ribs  351 , the fibers of the object  4  are practically incompletely severed. As a result, the unsevered fibers adversely entangle the shank  31 , thereby influencing the screwing speed of the screw  3 . Therefore, a rather great driving force has to be further exerted on the screw  3  for smoothly screwing into the object  4 . Consequently, the screw  3  has the shortcomings needed to be mended, i.e. a slower screwing speed, and a laborious screwing torque as well as a large resistance. 
       SUMMARY OF THE INVENTION 
       [0008]    The object of the present invention is to provide a versatile fastener for avoiding an unstable drilling as well as a cracked object. Thereby, the screwing speed could be promoted, the driving torque could be decreased, and the screwing efficiency could be elevated. 
         [0009]    The versatile fastener in accordance with the present invention mainly comprises a shank, a head portion as well as a drill point respectively disposed at two opposite ends of the shank, and a threaded portion spirally disposed on the shank. A cutting part with no threaded portion surrounded thereon is formed on the drill point. Wherein, the cutting part includes at least two flat areas and an accommodation disposed between any two flat areas at intervals. Moreover, the accommodating area has at least two connective cutting faces. Further, a first cutting edge and a second cutting edge are respectively formed at a convergence of each cutting face and the flat area. Thereby, the flat areas offer a stable supporting force while the first cutting edge and the second cutting edge are drilling into an object. Preferably, the drilled debris of the object could be speedily removed from the accommodating areas, thence preventing the object from a crack in view of a swaying screwing. Consequently, the screwing speed is promoted, the driving torque is dwindled, and the fastening efficiency is favorably encouraged. 
         [0010]    The advantages of the present invention over the known prior arts will become more apparent to those of ordinary skilled in the art by reading the following descriptions with the relating drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a schematic view showing a conventional screw; 
           [0012]      FIG. 2  is a schematic view showing another conventional screw; 
           [0013]      FIG. 3  is a schematic view showing a first preferred embodiment of the present invention; 
           [0014]      FIG. 4  is a bottom cross-sectional view showing a second preferred embodiment of the present invention; 
           [0015]      FIGS. 5 and 6  are partial cross-sectional views showing the first preferred embodiment; 
           [0016]      FIG. 7  is a bottom cross-sectional view showing the first preferred embodiment in using; 
           [0017]      FIGS. 8 and 9  are other partial cross-sectional views showing the first preferred embodiment; 
           [0018]      FIG. 10  is a bottom cross-sectional view showing a third preferred embodiment of the present invention; 
           [0019]      FIGS. 11 and 12  are partial cross-sectional views showing a fourth preferred embodiment of the present invention; 
           [0020]      FIGS. 13 and 14  are partial bottom cross-sectional views showing a fifth preferred embodiment of the present invention; 
           [0021]      FIG. 15  is a schematic view showing a sixth preferred embodiment of the present invention; 
           [0022]      FIG. 16  is a schematic view showing a seventh preferred embodiment of the present invention; 
           [0023]      FIG. 17  is a schematic view showing an eighth preferred embodiment of the present invention; and 
           [0024]      FIG. 18  is a bottom cross-sectional view showing a ninth preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0025]    Before describing in greater detail, it should note that the like elements are denoted by the similar reference numerals throughout the disclosure. 
         [0026]      FIG. 3  shows a first preferred embodiment of the present invention. A versatile fastener  5  comprises a shank  51 , a head portion  52  and a drill point  53  respectively disposed at two opposite ends of the shank  51 , and a threaded section  54  spirally disposed on the shank  51 . Wherein, a cutting part  55  with no threaded portion disposed thereon is formed on the drill point  53 , and at least one leading thread  56  outwardly extending from the cutting part  55 . Herein, by means of forming the cutting part  55  through the directly punching, a higher strength of the cutting part  55  could be accomplished. 
         [0027]    Further, the cutting part  55  includes at least two flat areas  551  and an accommodating area  552  defined between any two of the flat areas  551  at intervals. As it should be, the cutting part  55  could alternatively include several flat areas  551  as shown in  FIG. 4 . In this embodiment, the cutting part  55  adopts two flat areas  551  as well as one accommodating area  552  disposed between any two of the flat areas  551  at regular intervals. In addition, the accommodating area  552  has at least two connective cutting faces  553 . Wherein, a first cutting edge  554  and a second cutting edge  555  are respectively formed at a convergence of each of the cutting faces  553  and the flat areas  551 . Specifically, a junction formed by at least two cutting faces  553  on the accommodating area  552  is correspondingly disposed to an axis a (as indicated by an imaginary line) of the shank  51 . Further, a pointed part  556  (as shown in  FIG. 5 ) is formed at a congregation of the first cutting edge  554  and the leading thread  56 . Herein, a guiding area  557  (as shown in  FIG. 6 ) is defined at where the second cutting edge  555  and the leading thread  56  meet. In connection with the above concatenation, the pointed part  556  and the guiding area  557  are not set in the same level, thereby allowing the lengths of the first cutting edge  554  and the second cutting edge  555  to be divergent. Alternatively, as shown in  FIGS. 8 and 9 , the lengths of the first cutting edge  554  and the second cutting edge  555  are identical in view of the pointed part  556  and the guiding area  557  being set in the same level. Whereby, in this embodiment, the disposition of the cutting edges  554 ,  555  set by  FIGS. 5 and 6  is herein described as an example. 
         [0028]    Referring to  FIGS. 5 to 7 , in fastening, the leading thread  56  is set against an object  6 , thence permitting imparting an exertion on the head portion  52  (not shown) for the leading thread  56  to carry on the succeeding drilling of the fastener  5 . During the succeeding drilling, the pointed part  556  and the guiding area  557  respectively defined on the flat areas  551  are able to guide the debris generated from chipping out of the accommodating area  552 . Concurrently, the first and second cutting edges  554 ,  555  are gradually drilled into the object  6 . Herein, since the flat areas  551  provide a rather large supporting area between the object  6  and the fastener  5 , a more steady balance therebetween could be preferably carried out while the first and second cutting edges  554 ,  555  are continuously drilled into the object  6 . Thus, the fastener  5  within the object  6  does not sway randomly. Simultaneously, as the debris generated while screwing is swiftly expelled from the accommodating area  552 , the fastener  5  does not easily crack in view of the consecutively compressed debris and the swayed drilling. Thus, the steady supporting effect allows the fastener  5  and the object  6  to hold a preferable balance therebetween, thence bringing about a promoted fastening speed, a lowered fastening torque, and an elevated fastening effect. 
         [0029]    Referring to  FIG. 10 , a third preferred embodiment of the present invention is shown similar to that disclosed in the first preferred embodiment. Differently, an auxiliary cutting edge  558  could be extensively formed on brims of the first cutting edge  554  and of the second cutting edge  555 , respectively. In this embodiment, the auxiliary cutting edge  558  is extensively formed on the first cutting edge  554 . Accordingly, such auxiliary cutting edge  558  relating to a chord manner is skill in drilling into the object  6 , thereby providing a steady fixing effect as well as preventing the object  6  from cracking. 
         [0030]      FIGS. 11 and 12  show a fourth preferred embodiment of the present invention similar to that disclosed in the first preferred embodiment. Especially, the cutting part  55  is designed as being inclined with respect to an axis α of the shank  51 . Accordingly, the present invention still provides a stable balance between the fastener and the object as well as avoids the object from cracking. 
         [0031]      FIGS. 13 and 14  show a fifth preferred embodiment of the present invention whose related elements are defined alike to those in the first preferred embodiment. Differently, the convergence formed of the at least two cutting faces  553  of the accommodating area  552  is inconsistently disposed with respect to the axis a of the shank  51  (the axis is not herein shown). Thereby, the first and second cutting edges  554 ,  555  and the axis a of the shank  51  could be disposed either toward clockwise or counterclockwise. Therefore, by means of the cutting faces  553  rendering the cutting parts  55  able to set into different schemes, the fastener  5  favorably achieves a stable fixing effect and prevents the object  6  from cracking. 
         [0032]    Referring to  FIG. 15 , a sixth preferred embodiment of the present invention substantially comprises the shank  51 , the head portion  52 , the drill point  53 , the threaded portion  54 , and the cutting part  55 . Wherein, the fastening effect and the crack prevention effect are similar to those disclosed in the previous embodiments. Specifically, the shank  51  in this embodiment is designed by a polygon contour, and in the Figures the shank  51  adopts a quadrilateral. Therefore, since the shank  51  is able to adopt multiple designs, a rather large accommodating room for receiving debris could be provided in time of screwing. Accordingly, the fastening resistance is decreased, thereby preventing the object from split in view of the redundant debris adversely retained in the accommodating area. As a result, no matter the fastener  5  is applied to an elastic material or a wood material, a densely fastening effect could be favorably achieved. 
         [0033]    Referring to  FIG. 16 , a seventh preferred embodiment is shown. In this embodiment, the fastener  5  still comprises the similar elements, relations, and efficiencies as those disclosed in previous embodiments. Differently, the threaded portion  54  in this embodiment is designed by a polygon. Alternatively, both the shank  51  and the threaded portion  54  are designed by a polygon structure as shown in  FIG. 17 . It is noted that no matter how the shank  51  and the threaded portion  54  are configured, the threaded portion  54  consecutively provides the cutting part  55  with a stable cutting effect. Thereby, a prompt and less laborious fastening result could be still accomplished, and the debris would not be piled up in the accommodating area, which avoids the object from cracking. 
         [0034]    Referring to  FIG. 18 , a ninth preferred embodiment of the present invention still includes the most structures as the same as those mentioned in the first embodiment. It is characterized in that the cutting part  55  has at least two first flat areas  551  and a second flat area  551 ′ disposed between any two of the first areas  551 . Herein, a first cutting edge  554  as well as a second cutting edge  555  is respectively disposed on a convergence of each first flat area  551  and adjacent second flat area  551 ′. Moreover, the first cutting edge  554  and the second cutting edge  555  are designed by different lengths. Alternatively, accompanying with  FIGS. 5 and 6  as well as  8  and  9 , a pointed part  556  is connectively formed by the first cutting edge  554  and the leading thread  56 , and a guiding area  557  is also defined at a junction formed by the second cutting edge  555  and the leading thread  56 . Thereby, the first and second cutting edges  554 ,  555  designed by divergent lengths permit the cutting part  55  to render the versatile fastener  5  able to attain a stable fastening efficiency as well as a crack prevention function. 
         [0035]    To sum up, the present invention takes advantage of the cutting part providing with at least two flat areas as well as an accommodating area disposed between the flat areas at intervals. Whereby, a stable supporting is conduced between the fastener and the object for the purpose of avoiding the swaying generated from the insufficient supporting force. Further, the instant guidance of the debris through the accommodating area also prevents the object from being cracked due to the jam of the debris. Therefore, the present invention facilitates promoting the fastening speed and the screwing efficiency as well as decreasing the screwing torque. 
         [0036]    While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.