Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
SMALL-SIZED ELECTROMAGNETIC SPEAKER
Document Type and Number:
Japanese Patent JPS586700
Kind Code:
A
Abstract:

PURPOSE: To reduce unevenness of sound pressure aproximately at a resonance point and to decrease a distortion factor, by using a printed substrate as the 1st diaphragm, sticking the circumference to a resonator by ultrasonic-wave welding, and arranging the 2nd diaphragm, a driving part, and a driving-part tension leaf.

CONSTITUTION: The oscillation of the 2nd diaphragm 38 driven directly by a driving part is transferred through the air spring of an air room 22 to the 1st diaphragm 18, which sounds directly. To allow the 1st and 2nd diaphragms 18 and 38 to oscillate at resonance frequencies f1 and f2 among three resonance frequencies shown by characteristics (c), the effective mass m2 of the 1st diaphragm 18 should be about 1/10 as great as the effective mass m1 of the 2nd diaphragm 38, and while compliance is considered, the size and thickness of a pattern 17 are set. In the graph, fa depends upon acoustic capacitance, inertance and radiation reactance determined by the sizes of a resonance space 24 and a sound radiation cylinder 15. Plastic member is used for the 1st diaphragm 18, so the frequency-sound pressure characteristics have decreased Q values at resonance points f1 and f2.


Inventors:
HORIKOSHI ICHIROU
Application Number:
JP1981000104845
Publication Date:
January 14, 1983
Filing Date:
July 03, 1981
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SEIKO INSTR & ELECTRONICS
International Classes:
H04R13/00; H04R11/02; (IPC1-7): H04R13/00