METHOD OF MAKING A FAN-TYPE DIAPHRAGM WITH A DIAMOND-LIKE CARBON COATING Russian patent published in 2024 - IPC H04R7/14 H04R31/00 

FIELD: acoustics.

SUBSTANCE: invention relates to acoustics, in particular to a method of making a radiating diaphragm for a loudspeaker head. Method involves making a fan-type diaphragm from paper. Diaphragm is put through the central hole in it on the metal tooling in the form of a cylinder and placed on the planetary rotation mechanism in the vacuum chamber. Vacuum of at least 3×10^-3 Pa is set in the chamber and the surface of the diaphragm is cleaned by accelerated argon ions with energy of 500–2,000 eV using a gas ion source, then initiating a pulsed electric arc discharge on a graphite cathode and obtaining a pulsed flow of carbon plasma with ion energy of 40–100 eV, with the help of which a diamond-like carbon coating is formed on the fan-type diaphragm. Diaphragm temperature is maintained within 300–350 K by controlling pulse repetition rate of electric arc discharge 1–10 Hz.

EFFECT: wider range of frequency response of the acoustic device.

1 cl, 2 dwg