Tightening frame for a drum

#1. Field of the Invention

#The present invention relates to a drum tightening frame used in, for instance, bass drums, snare drums and marching drums and more particularly to a structure for mounting a tightening frame on a drum body.

#2. Prior Art

#FIG. 1 is a top view of the drum tightening frame according to the present invention;

#FIG. 2 illustrates one of the bolt attachment openings formed in the drum tightening frame;

#FIG. 3 is a sectional view of one embodiment of the drum tightening frame according to the present invention that uses magnetic force;

#The present invention will be described in detail below with reference to the embodiments illustrated in the accompanying drawings. The description will be made based upon a snare drum that comprises a drum main body 1, drumheads 2, and a head supporting and tensioning assembly 3.

#In FIGS. 1 and 2, the drum tightening frame 20 is, in the same manner as in the conventional tightening frame 6 shown in FIG. 6, made of a metal consisting of a molded product such as aluminum, etc. and is formed in a substantially cross-sectional L shape (see FIGS. 3 and 4 or see the corresponding prior art frame 6 in FIG. 6). The drum tightening frame 20 is thus comprised of a cylindrical portion 20A and a ring-form circular plate portion 20B. The cylindrical portion 20A extends in the axial direction of the drum main body 1 and has a diameter that is larger than the external diameter of the drum main body 1 and smaller than the external diameter of the head frame 5. The ring-form circular plate portion 20B extends in the direction perpendicular to the axis of the drum maim body 1 and is integrally formed with the cylindrical portion 20A so that the ring-form circular plate portion 20B is located closer to the axial center of the drum main body 1 than the cylindrical portion 20A is. Furthermore, eight bolt attachment portions 21 that have bolt attachment openings 22 are disposed in the circular plate portion 20B of the drum tightening frame 20 at equal intervals in the circumferential direction.

#Each of the bolt attachment portions 21 has an arc-shaped protruding portion 21A that protrudes outward from the outer circumference of the circular plate portion 20B. Furthermore, the bolt attachment opening 22 is formed in the boundary area between this protruding portion 21A and the circular plate portion 20B. The protruding portion 21A is formed in each bolt attachment portion 21; and this structure is taken so as to locate the bolt attachment opening 22 at positions separated from the cylindrical portion 20A and so as not to increase the external diameter of the circular plate portion 20B, thus allowing tightening bolts 8 in the bolt attachment opening 22 to be easily rotated by a tuning key (not shown).