Abstract:
In a drum assembly, the combination comprising a drum shell having opposite ends, drumheads at the opposite ends of the shell, and annular drumhead supports carried by the shell, the supports having head supporting annular rim zones with different angular configurations comprising a drum shell having opposite ends, drumheads at the opposite ends of the shell, and annular drumhead supports carried by the shell, the supports having head supporting annular rim zones with different angular configurations.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to drum structure, and more particularly to differential supporting of drum heads, as at two different diameters, at opposite ends of a drum.  
           [0002]    In the past, drumheads at opposite ends of a drum were supported in like manner, as at equal diameters. It has now been found that the resonating effect of a drum when struck at a drumhead can be desirably enhanced if the two drumheads are differentially supported, at rims.  
         SUMMARY OF THE INVENTION  
         [0003]    It is a major object of the invention to provide an improved drum assembly that comprises, in combination:  
           [0004]    a) a drum shell having opposite ends,  
           [0005]    b) drumheads at said opposite ends of the shell,  
           [0006]    c) and annular drumhead supports carried by the shell,  
           [0007]    d) said supports having head supporting annular rim zones with differing angular configurations.  
           [0008]    It is another object of the invention to provide such rim zones having or defining different bevels, and which are typically characterized by different angularities.  
           [0009]    An additional object is provision of such rim zones characterized by different diameters, whereby the diameters and therefore the resonating areas of the two drumheads are different.  
           [0010]    Yet another object is the provision of different diameter drumheads where two diameters differ by between 1 and 10%. 
       
    
    
       [0011]    These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:  
       DRAWING DESCRIPTION  
       [0012]    [0012]FIG. 1 is a perspective view of a prior art drum;  
         [0013]    [0013]FIG. 2 is a vertical section taken through one side of the FIG. 1 prior art drum;  
         [0014]    [0014]FIG. 3 is a section showing different bevels at the head supporting rim zones of a drum; and  
         [0015]    [0015]FIG. 4 is a view like FIG. 3, showing drumheads stretched over the differential diameter rim zones. 
     
    
     DETAILED DESCRIPTION  
       [0016]    In FIGS. 1 and 2, a prior art (see U.S. Pat. No. 5,377,576) drum  10  has a shell with cylindrical sections located in axially end-to-end position, at least a first section consisting of wood and at least second and third sections consisting of metal. In the example, the shell  11  has a first wall section  12  consisting of wood, a second wall section  13  consisting of metal, and a third wall section  14  consisting of metal. The section  12  is preferably located between sections  13  and  14 , so that drumheads  15  and  16  may stretch over annular beveled metallic edges  17   a  and  18  that do not “weather” or otherwise change with atmospheric or other conditions. Sections  12  and  13  may have telescopic interfit with section  11 , as for example at radially overlapping portions  12   a  and  13   a , and radially overlapping portions  12   b  and  14   a . Such connections are also referred to as “pin and box” connections, providing high radial and axial stability. Sections  13  and  14  consist of brass, and section  12  of maple, and their interfits may be tight. A wall consisting of one material may be employed.  
         [0017]    Means is also provided for retaining the drumheads on the drum, including flanges at axial ends of the drum, retainers on one of the sections, and adjustable tensioning means interconnecting the flange means and retainer means. In the example, flange structure  20  is provided in association with metal section  13  of the shell, and flange structure  21  in association with metal section  14  of the shell. Retainer elements  23  are spaced about and adjacent the outer surface  24  of wooden section  12 , mid-way between metal sections  13  and  14 , and the elements  23  may have circular cross sections as shown and consist of brass. The elements  23  carry tubular holders  25  projecting vertically and parallel to the drum axis, but in axially opposite directions. Tightening adjustment fasteners  26  project radially through the shell section  12  to affix the elements  23  to the outer surface of the section  12 .  
         [0018]    The upper flange structure  20  has an upwardly extending annular rim portion  32  extending above the level of drumhead  15 , a medial annular flange portion  33  extending radially outwardly below the level of  32 , for transmitting head tightening loading, and a lower annular portion  34  extending downwardly from the outer extent of  33 .  
         [0019]    A tightening adjustment fastener or tensioner rod  36  extends downwardly through  33 , and its lower end has external threads  37  that interfit rotatably internal threads in upper holder  25 . Note fastener head  36   a  bearing on the upper surface of  33 . The lower surface of  33  exerts downward loading onto a retention ring  38  to which drumhead  15  is suitably attached, for tightening (or loosening) same, by drawing the head over  17 .  
         [0020]    Likewise, lower flange structure  21  has a downwardly extending annular rim or flange portion  43  extending below the level of drumhead  16 , a medial annular portion  44  extending radially outwardly above the level of  42  for transmitting head tightening loading, and an upper annular portion  44  extending upwardly from outer extent of  43 . A tightening adjusting fastener or tensioner rod  46  extends upwardly through  42 , and has external threads  47  that interfit rotatably the internal threads in lower holder  25 . Note fastener head  46   a  bearing on the lower surface of  42 . The upper surface of  43  exerts upward loading onto lower retention ring  48  to which drumhead  16  is suitably attached, for tightening (or loosening) same, i.e. over bevel  18 . Accordingly, the drumheads are individually adjustable; however, it is found that the tensioner rods  36  and  46  can loosen as by rotation in untightening direction, during or as a result of drumming.  
         [0021]    Referring now to FIG. 3, rim zones at opposite ends of a drum shell  130  are indicated at  50  and  51 . Those zones taper toward apices  50   a  and  51   a , at zone edges, which may be sharp or slightly convex. Opposite tapering and generally flat sides or flanks of the rim zones appear at  52  and  53 , and  54  and  55 . The acute angularities of beveled sides  52  and  53  are indicated at α and β, respectively. Sides  52  and  54  face inwardly toward the drum axis  55 . It will be noted that angle β exceeds angle α, and that annular apex  50   a  is therefore closer to axis  55  in a radial direction than annular apex  51   a . Note that radial dimension  51   a ′ exceeds radial dimension  50   a ′, and the differential is between 0.5 and 10%. Note also that flanks  54  and  55  also extend at different angles relative to axis  65 .  
         [0022]    [0022]FIG. 4 is like FIG. 3, but shows drum heads  60  and  61  stretched over the annular apices  50   a  and  51   a , and retained at  60   a  and  61   a . When either drumhead is struck by a beater shaft, the audible resonation of the drum exceeds resonation that occurs when both heads are of the same supported diameter as for example the diameter of head  60 .