Percussion instrument, drumhead for percussion instrument, mold for manufacture of drumhead, and manufacturing method of drumhead

Abstract

A percussion instrument includes: a cylindrical shell portion having an open upper surface side; and a drumhead stretched to be installed on the upper surface side of the shell portion, wherein the drumhead includes: a membrane formed of a membranous material, having a struck head portion configured as a striking face to be struck by a performer and an outer periphery located on an outer circumferential side of the struck head portion; and an annular frame formed of a resin material and having the outer periphery of the membrane fixed thereto, and the drumhead is integrally formed by the membrane and the frame by injection molding.

What is claimed is: 
     
         1 . A drumhead for a percussion instrument comprising:
 a membrane formed of a membranous material, comprising   a struck head portion configured as a striking face to be struck by a performer; and   an outer periphery located on an outer circumferential side of the struck head portion; and   an annular frame formed of a resin material by injecting the resin material that has been melted into a mold and hardening the resin material,   wherein the outer periphery of the membrane is fixed on the frame, the membrane and the frame are integrally formed, and   wherein the resin material is thermoplastic resin such that the annular frame is released from the mold after the resin being hardened.   
     
     
         2 . A percussion instrument comprising:
 a cylindrical shell portion having an open upper surface; and   the drumhead according to  claim 1 ,   wherein the drumhead is stretched to be installed on the open upper surface.   
     
     
         3 . A percussion instrument, comprising
 a cylindrical shell portion having an open upper surface side; and   a drumhead stretched to be installed on the upper surface side of the shell portion, wherein the drumhead comprises   a membrane formed of a membranous material, comprising   a struck head portion configured as a striking face to be struck by a performer; and   an outer periphery located on an outer circumferential side of the struck head portion;   an annular frame formed of a resin material, wherein the outer periphery of the membrane is fixed on the frame, the membrane and the frame are integrally formed by injection molding, and the membrane is formed by a mesh material, and wherein the resin material of the frame is excluded from entering the struck head portion of the drumhead; and   a plurality of tightening bolts that fix the frame to the shell portion while imparting tension to the struck head portion and are threaded by external threads to be screwed into internal threads disposed on the shell portion or the frame, wherein   the frame comprises a plurality of bolt holes that allow the tightening bolts to be inserted thereinto.   
     
     
         4 . The percussion instrument according to  claim 3 , comprising an annular hoop that imparts tension to the struck head portion by pressing down the outer periphery while the struck head portion is disposed on the upper surface side of the shell portion, wherein
 the hoop is integrally formed with the frame.   
     
     
         5 . The percussion instrument according to  claim 3 , wherein the membrane is fixed on the frame while an outer edge of the outer periphery is disposed inside the frame. 
     
     
         6 . The percussion instrument according to  claim 3 , wherein the frame comprises
 a lower relief portion depressed on a lower surface side of the frame; and   a gate trace formed by injection of a resin material during the molding is formed on an inner wall surface of the lower relief portion.   
     
     
         7 . The percussion instrument according to  claim 6 , wherein the membrane comprises a first cutting-off portion formed by cutting off a part of the outer periphery of the membrane. 
     
     
         8 . The percussion instrument according to  claim 7 , wherein the frame is formed at a position such that the gate trace formed by injection of the resin material during the molding corresponds to the first cutting-off portion. 
     
     
         9 . The percussion instrument according to  claim 3 , wherein a length of the membrane from an inner edge of the outer periphery in a radial direction is set smaller than a shortest distance from the inner edge to an upper surface of the frame. 
     
     
         10 . The percussion instrument according to  claim 3 , wherein the outer periphery of the membrane has an outer diameter set greater than a diameter of a virtual circle that passes through the plurality of the bolt holes. 
     
     
         11 . The percussion instrument according to  claim 10 , wherein the membrane comprises a plurality of cutting-off portions formed by cutting parts of the outer periphery corresponding to positions where the plurality of bolt holes are formed. 
     
     
         12 . The percussion instrument according to  claim 3 , wherein the outer periphery of the membrane is fixed on the frame while the struck head portion has looseness. 
     
     
         13 . The percussion instrument according to  claim 3 , wherein the membrane comprises a plurality of the membrane parts, and one of the plurality of the membrane parts is set looser than the other of the plurality of the membrane parts. 
     
     
         14 . The percussion instrument according to  claim 3 , wherein the outer periphery of the membrane is fixed on the frame while the struck head portion has tension imparted thereto. 
     
     
         15 . The percussion instrument according to  claim 3 , wherein an outer edge of the struck head portion protrudes further upward than the outer periphery of the membrane. 
     
     
         16 . A drumhead for a percussion instrument comprising:
 a membrane formed of a membranous material, which is a mesh material, comprising a struck head portion configured as a striking face to be struck by a performer and an outer periphery located on an outer circumferential side of the struck head portion; and   a frame formed of a resin material, wherein the outer periphery of the membrane is fixed on the frame, and the membrane and the frame are integrally formed, wherein the frame comprises:
 an inner circumferential portion, where the resin material enters holes of the mesh material of the membrane; and 
 an outer circumferential portion, where the membrane is not formed. 
   
     
     
         17 . A percussion instrument comprising:
 a cylindrical shell portion having an open upper surface; and   the drumhead according to  claim 16 ,   wherein the drumhead is stretched to be installed on the open upper surface.