DIAPHRAGM FOR SPEAKER

• Main Author: KINOSHITA KATSUMI
• Format: Patent
• Language: English
• Published: 27.04.1982
• Subjects: DEAF-AID SETS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKEACOUSTIC ELECTROMECHANICAL TRANSDUCERS; PUBLIC ADDRESS SYSTEMS

PURPOSE:To absorb the oscillation at edge smoothly, to reduce the distortion in speaker and to improve the frequency characteristics, by processing a part or all the shells of a polymer graphite diaphragm with swollen or soluble solvent. CONSTITUTION:A polymer graphite sheet 1 is clipped between an upper metallic mold 2 incorporating a heater 2a and a lower metallic mold 3 forming a recess 3a of cone shape on the upper side, and after heating and softening the sheet 1 with the heater 2a, a cone 1' is formed by absorption with reduced pressure by the duct 3b of the lower metallic mold 3. The edge external circumference of the cone 1' formed is immersed in a solvent tank 4 and solvent processing is made to a part of the shell. A mask member 5 is coated by leaving the desired part of the cone 1' and solvent is sprayed from a nozzle 7 while rotating the axis 6 as a center. The frequency characteristics can be improved by absorbing the oscillation at the edge.