Abstract:
A masonry anchor includes a head and a body integral to the head and extending therefrom. At least one helical male thread surrounds the body and includes a leading face and a trailing face substantially perpendicular to the body disposed between the leading face and the head. The trailing face intersects the leading face at a thread crest.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The subject matter disclosed herein relates to screw-type fasteners. More particularly, the subject invention relates to screw type masonry anchors. 
         [0002]    In order to secure fixtures and other attachments to masonry, a screw-type anchor is often used. In anchors of this type, a helical cutting thread is formed on the shank of the anchor and acts to cut and tap the wall of a hole in the masonry when the anchor is turned into the hole, thereby retaining the anchor to the masonry. Typically, the cutting thread has a v-shaped cross-section wherein the flanks of the thread intersect at an included angle of 55-60 degrees. The diameter of a crest of the cutting thread is greater than the diameter of the hole into which the anchor is inserted so the cutting thread cuts the wall of the hole when inserted. In some anchors, multiple cutting threads, each having a crest diameter greater than the hole diameter may be utilized to increase a holding power of the anchor. The art would well receive a masonry screw with further improved holding power to retain attachments to masonry. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0003]    According to one aspect of the invention, a masonry anchor includes a head and a body integral to the head and extending therefrom. At least one helical male thread surrounds the body and includes a leading face and a trailing face substantially perpendicular to the body disposed between the leading face and the head. The trailing face intersects the leading face at a thread crest. 
         [0004]    These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0006]      FIG. 1  illustrates a top view of an embodiment of a masonry screw; 
           [0007]      FIG. 2  illustrates a side view of an embodiment of a masonry screw; 
           [0008]      FIG. 3  illustrates another side view of an embodiment of a masonry screw; 
           [0009]      FIG. 4  illustrates a cross-sectional view of the masonry screw of  FIG. 3 ; 
           [0010]      FIG. 5  illustrates an end view of an embodiment of a masonry screw; and 
           [0011]      FIG. 6  illustrates an enlarged view of a portion of  FIG. 4 . 
       
    
    
       [0012]    The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0013]    Shown in  FIG. 1  is a top view of an embodiment of a masonry screw  10 . The masonry screw  10  includes a head  12 , which in some embodiments is hexagonal in configuration. Referring to  FIG. 2 , the masonry screw  10  includes a threaded body  14  extending from the head  12 . The body  14  includes at least one male helical thread  16  extending along the body  14 . In some embodiments, two threads  16  are utilized, but it is to be appreciated that other quantities of threads  16 , for example, 3 or 4 threads  16  may be utilized. In some embodiments, as shown in  FIGS. 3 and 4 , a first thread  18  is separated from a second thread  20  by a distance  22 , and a first lead  24  of the first thread  18  is in a different circumferential position than a second lead  26  of the second thread  20 . For example, the first lead  24  may be positioned 180 degrees from the second lead  26 . 
         [0014]    A first crest diameter  28  of the first thread  18  and a second crest diameter  30  of the second thread  20  are greater than a diameter of a hole in workpiece (not shown), for example masonry, into which the screw  10  is inserted. Thus, when the screw  10  is turned into the hole, the first thread  18  and second thread  20  cut female threads into the hole to increase a holding capability of the screw  10  in the workpiece. In some embodiments, as shown in  FIG. 4 , the first crest diameter  28  is greater than the second crest diameter  30 . Referring to  FIG. 4 , the first thread  18  and/or the second thread  20  may include a plurality of notches  32 , which in some embodiments are v-shaped and extend inwardly from the first crest diameter  28 . The notches  32  are arrayed along the first thread  18  and/or the second thread  20  and may be located approximately every 120 degrees about the screw  10 , as best shown in  FIG. 5 . 
         [0015]    Referring to  FIG. 6 , the first thread  18  includes a leading face  34  and a trailing face  36  which intersect at a first crest  38 . As shown in  FIG. 6 , the trailing face  36  is substantially perpendicular to the body  14 . The leading face  34  is disposed between the trailing face  36  and a tip  40  (shown in  FIG. 4 ) of the screw  10 . As shown in  FIG. 6 , the leading face  34  extends from the body  14  and may, in some embodiments, be a substantially straight line in cross-section. The leading face  34  may have other cross-sectional shapes, however, including curved or arcuate. The second thread  20  is disposed at a distance  42  from the first thread  18 . The second thread  20  may be configured substantially like the first thread  18 . In some embodiments, however, as shown in  FIG. 6 , the second thread  20  is a male thread with a substantially v-shaped cross-section. 
         [0016]    Referring again to  FIG. 3 , the tip  40  of screw  10  is configured as a nail point. In other embodiments, however, the tip  40  may have other configurations. For example, the first thread  18  and/or the second thread  20  may extend substantially to the tip  40 . 
         [0017]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.