JPS6313598B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has moderate compliance with the force in the axial direction of the voice coil bobbin, good linearity even at large amplitudes, and The present invention provides an electrodynamic speaker equipped with a damper having sufficient regulating force against force.

FIG. 1 shows a conventional electrodynamic speaker.
In FIG. 1, 1 is a yoke in which a center pole 2 is integrally formed, 3 is an annular magnet fixed on the yoke 1, and 4 is an annular plate fixed on the magnet 3. An annular magnetic gap is formed between the circumferential surface and the center pole 2. 5 is a frame fixed on the plate 4, 6 is a diaphragm, and this diaphragm 6
The outer periphery of is supported by the frame 5 via an edge member (not shown). A coil bobbin 7 is fixed to the diaphragm 6, and a voice coil 8 is wound around the coil bobbin 7. 9 is a corrugated damper made by impregnating cloth with resin and heat molding it;
The inner peripheral part of this damper 9 is fixed to the coil bobbin 7, and the outer peripheral part is fixed to the frame 5. 1
0 is a dust cap attached to the diaphragm 6.

In the conventional electrodynamic speaker described above, the damper 9 restricts the movement of the coil bobbin 7 in a direction perpendicular to the axis thereof, and the coil bobbin 7 moves in the axial direction.

The conditions required of the damper 9 that holds the coil bobbin 7 are as follows: (a) It must have appropriate compliance in the axial direction of the coil bobbin and have good linearity even at large amplitudes.

(b) The coil bobbin must have sufficient stiffness in the radial direction.

However, since the corrugated damper 9 in the conventional example has a sufficiently high stiffness in the radial direction of the damper 9 to satisfy the condition (b) above, the condition (a) above is not satisfied, and as shown in FIG. As shown by A in FIG. 1, there was a drawback that the force-displacement characteristics of the damper 9 became non-linear when the amplitude was large. Therefore, in conventional speakers, harmonic distortion occurs in the low frequency range.

The present invention eliminates the above-mentioned conventional drawbacks, and the structure of a damper according to an embodiment of the present invention will be explained below with reference to FIGS. 3 to 5.

In FIGS. 3 to 5, reference numeral 11 denotes a rectangular central support portion in which a hole 12 into which a coil bobbin is inserted and fixed is formed. 14a, 14
They are connected by b, 14c, and 14d. These four damper pieces 14a to 14d all have the same structure, so the details of one damper piece 14a will be explained.

15 and 16 are slits formed between the central support portion 11 and the outer peripheral portion 13;
5 and 16, the damper piece 14a is divided into three parts along the outer periphery of the central support part 11.
Third divided pieces 17a, 17b, and 17c are arranged in parallel. Each of the divided pieces 17a, 17b, and 17c has a tangent portion 18a, 18b, and 18c formed at its center, respectively. That is, each divided piece 17a, 17b,
17c are the contact portions 18a, 18b, 18, respectively.
Two surface elements 19a, 19b connected by c,
Two surface elements 20a, 20b, two surface elements 21a,
21b.

A divided piece 17a consisting of surface elements 19a and 19b, and a divided piece 17c consisting of surface elements 21a and 21b.
are bent so as to be convex upward with respect to the surfaces of the central support portion 11 and the outer peripheral portion 13, and the surface elements 20a,
The central divided piece 17b consisting of 20b is bent so as to be convex downward. As shown in FIG. 4, when the damper of this embodiment is viewed from the side, the surface elements 20a, 20b of the divided piece 17b, the surface elements 19a, 19b of the divided piece 17a, and the divided piece 17.
A quadrilateral is formed by the surface elements 21a and 21b of c. Note that each surface element 19a, 19b, 20a, 20
Reinforcing ribs are formed on b, 21a, and 21b to increase the strength of the surfaces.

Further, a bent part 22 is formed at the boundary between each divided piece 17a, 17b, 17c and the central support part 11, and a bent part 22 is formed at the boundary between each divided piece 17a, 17b, 17c and the outer peripheral part 13. 23 is formed.

The damper 24 is constructed by forming four damper pieces having the above structure.

FIG. 6 shows the principle of operation of the damper 24 in the above embodiment. In FIG. 6, solid lines indicate a stationary state, and broken lines indicate an upwardly displaced state. When viewed from the side, the damper piece 14a has a quadrilateral shape of a, b, c, and d as shown in FIG. , d are transformed into quadrilaterals a, b', c', and d'. Furthermore, the sixth
The reason why point c is displaced to point c' in the figure and not displaced in the radial direction is because damper piece 14a is restricted by damper pieces 14b and 14d on both sides.

The above-mentioned damper is made by heat-molding cloth impregnated with resin, for example, to form the central support portion 11, damper pieces 14a, 14b, 14c, and 14.
d. The outer peripheral portion 13 can be formed integrally.

In the above embodiment, the damper pieces are connected to each side of the quadrilateral center support portion, but the center support portion is not limited to a quadrilateral shape, and may be any polygon. Further, in the above embodiment, each damper piece is composed of three divided pieces, but it may be composed of two divided pieces, or four or more divided pieces.

The present invention has the above-mentioned configuration, and is shown in FIG.
As shown in , the linearity of the force-displacement characteristic is improved, low-frequency distortion at large amplitudes is reduced, and the low-frequency reproduction band is expanded.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main parts of a conventional electrodynamic speaker, FIG. 2 is a force-displacement characteristic diagram of the damper of the conventional electrodynamic speaker and the damper of the electrodynamic speaker of the present invention, and FIG. A top view of a damper of an electrodynamic speaker according to an embodiment of the present invention, FIG.
5 is a perspective view of the damper, and FIG. 6 is an explanatory diagram of the operation of the damper. 7...Coil bobbin, 8...Voice coil, 1
1... Central support part, 12... Hole, 13... Outer periphery, 14a, 14b, 14c, 14d... Damper piece, 15, 16... Slit, 17a, 17
b, 17c...divided piece, 18a, 18b, 18c
...Bending portion, 19a, 19b, 20a, 20b,
21a, 21b... surface element, 22, 23... bent portion, 24... damper.

Claims (1)

[Scope of Claims] 1. A regular polygonal central support portion to which a coil bobbin is fixed, a plurality of damper pieces connected to each outer peripheral portion of the central support portion via bent portions, and each of the damper pieces. It consists of an outer circumferential part connected to an outer circumferential part via a bent part, and each of the damper pieces has two parts arranged in parallel.
A damper composed of two or more divided pieces, each divided piece consisting of two surface elements connected via a bending part, and each divided piece being bent alternately to convex upward and convex downward. An electrodynamic speaker equipped with 2. The electrodynamic speaker according to claim 1, wherein a reinforcing rib is formed on each surface element constituting the damper.