JPS6120493A - Coaxial flat plate speaker unit - Google Patents

Abstract

PURPOSE:To simplify the constitution and to obtain a high sound pressure by constituting in such a way that a woofer disphragm, cylindrical acoustic filtering fixed to the inner peripheral edge of this woofer diaphragm and tweeter having a cylindrical frame for approaching and facing the inner peripheral surface of the acoustic filtering on the outer peripheral part are provided. CONSTITUTION:Numeric numbers 6, 7, 8 and 10 show an outer edge for supportig the outer peripheral edge of a woofer disphragm 5, cylindrical acoustic filterring 7 fixed to the inner peripheral edge of fhe woofer disphragm 5, tweeter having a cylindrical frama 9 for approaching and facing the inner peripheral surface of the acoustic filterring 7 and circular space in a simple shape obtained by modifying an inner edge frame 4, respectively. With this constitution, the length of the acoustic filtering 7 and an inverval between the acoustic filterring 7 and the cylindrical frame 9 of the tweeter 8 are decided by an expression I, which decides every volue so that a resonance frequency fr of the acoustic filter can be below a minimum resonance frequency or the woofer. Thus, when an inner edge is abolished and the inner edge frame is altered to the spacer 10, a high sound pressure can be obtained with simple constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a coaxial flat speaker unit.

Conventional Structures and Problems Generally, coaxial flat speaker units have a structure in which a woofer diaphragm (1) is supported by an inner edge (2) and an outer edge (3), as shown in FIG. Because there is, Utsuji (
An inner edge frame (4) was required to support 2).

However, the presence of the inner edge frame (4) made the 11 structure complicated, and there was a problem in that direct materials and man-hours were required. Furthermore, the area of the diaphragm of the woofer diaphragm (1) is reduced by the inner and outer edges (21F3), making it difficult to obtain high sound pressure.

Purpose of the Invention The present invention solves the above-mentioned conventional problems, and provides a coaxial flat plate which has a simpler structure than the conventional coaxial flat plate speaker unit and which can obtain high sound pressure by increasing the area of the diaphragm of the woofer diaphragm. The purpose is to provide speaker units.

a cylindrical acoustic filter ring fixed to the inner peripheral edge of the inventive configuration;
The structure includes a tweeter having a cylindrical frame on the outer periphery that closely opposes the inner periphery of the acoustic filter ring, thereby making it possible to have a simpler structure than a conventional coaxial flat speaker unit. At the same time, it is possible to obtain a high sound pressure by increasing the area of the diaphragm of the woofer diaphragm.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In the figure, (5) is the woofer diaphragm, (6) is the outer edge that supports the outer edge of the woofer diaphragm (5), and (7) is the cylindrical edge that is fixed to the inner edge of the woofer diaphragm (5). An acoustic filter ring (8) is a tweeter having a cylindrical frame (9) on its outer circumference that closely faces the inner circumferential surface of the acoustic filter ring (7), GO is an inner edge frame (4) shown in FIG. ) is a ring-shaped spacer with a simple shape.

In such a configuration, the acoustic filtering (7)
length, acoustic filtering (7) and tweeter (8)
The spacing between the cylindrical frames (9) is determined by the following formula.

However, fr: Resonant frequency of the acoustic filter S: Cross-sectional area of the acoustic filter L: Length of the acoustic filter ring V: Volume of the cabinet C: Propagation speed of sound wave In the above equation, the resonant frequency fr of the acoustic filter is the lowest resonance of the woofer. Determine each value so that it is equal to or less than the frequency.

As a result, high sound pressure can be obtained with a simple structure by eliminating the inner edge (2) shown in FIG. 1 and replacing the inner edge frame (4) with the spacer α0.

Effects of the Invention According to the present invention, since the inner edge provided in the conventional coaxial flat speaker unit is abolished, the inner edge frame that supports it is also abolished and replaced with a simple shaped member such as a spacer. be able to. Therefore, it is possible to have a simpler structure than the conventional coaxial flat speaker unit, and it is also possible to obtain high sound pressure by increasing the area of the diaphragm of the woofer diaphragm. Furthermore, compared to expanding the diaphragm area inward using a strong magnet in the tweeter or expanding the diaphragm area to the outer periphery, the expansion of the diaphragm area according to the present invention is advantageous in terms of cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a conventional coaxial flat speaker unit, and FIG. 2 is a sectional view showing an embodiment of the coaxial flat speaker unit of the present invention. (5)...woofer diaphragm, (7) acoustic filtering, (8) tweeter, (9) tubular frame agent
Yoshihiro Morimoto Figure 1? Cause

Claims (1)

[Claims] 1. A tweeter including a woofer diaphragm, a cylindrical acoustic filter ring fixed to the inner peripheral edge of the woofer diaphragm, and a cylindrical frame on the outer periphery that closely faces the inner peripheral surface of the acoustic filter ring. A coaxial flat speaker unit with