JPS5943876B2 - electrodynamic speaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has appropriate compliance with respect to the force in the axial direction of the voice coil bobbin, good linearity even at large amplitudes, and furthermore, has a suitable compliance with respect to the force in the direction perpendicular to the axis of the voice coil bobbin. The present invention provides an electrodynamic speaker equipped with a damper having a sufficient regulating 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 inner peripheral surface and the center pole 2.

5 is a frame fixed on the plate 4, 6 is a diaphragm, and the outer periphery of this diaphragm 6 is an edge member (not shown).
It is supported by the frame 5 via.

A coil bobbin 7 is fixed to the diaphragm 6, and a bobbin coil 8 is wound around the coil bobbin 1.

Reference numeral 9 denotes a wave-shaped damper made by impregnating cloth with resin and heat-forming the damper.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.

10 is a dust camp attached to the diaphragm 6.

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

The conditions required of the damper 9 that holds the coil bobbin 7 are (a) appropriate compliance in the axial direction of the coil bobbin and good linearity even at large amplitudes, (b) diameter of the coil bobbin It must have sufficient stiffness in the direction, etc.

However, since the corrugated damper 9 in the above conventional example has a sufficiently high radial stiffness of the damper 9 to satisfy the above conditions aαb), the above condition (a) is not satisfied, and as shown in FIG. As shown in A, damper 9
The disadvantage was that the Kerr displacement characteristics of the oscillator 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 one embodiment of the present invention will be described below with reference to FIGS. 3 to 5.

Figures 3 to 5 show a damper 1 used in an embodiment of the present invention.
1 is shown.

This damper 11 is constructed by bonding two damper plates 12 and 13 together at necessary locations.

Each damper plate 12, 13 has the same shape, and has a rectangular central support part 15a, 15b in which a hole 14a, 14b into which a coil bobbin is inserted and fixed is formed, and each outer periphery of this central support part 15, 115b. Bent parts 16a, 16
Four damper pieces 17a, 17b connected via b
.

17c, 17d, 18a, 18b, 18c, 18d An outer peripheral support portion 20 connected to the outer periphery of each damper piece 17a to 17d, 18a to 18b via bent portions 19a and 19b.
a, 20b, two damper plates 12.13
central support portions 15a and 15b, and outer peripheral support portion 20a.
and 20b are bonded to each other.

Each of the damper pieces 17a to 17d, 18a to 18d is the bent portion 16a.

16b and a bent portion 21 parallel to the bent portions 19a and 19b.
Two surface elements 22a, 22 connected via a, 21b
b, 23a, 23b, each surface element 22a, 22
Reinforcing ribs are formed on b, 23a, and 23b to increase surface rigidity.

Damper pieces 17a to 17 consisting of surface elements 22a and 22b
d is bent to be convex upward, and surface elements 23a, 2
The damper pieces 18a to 18d consisting of 3b are bent so as to be convex downward, and as shown in FIG.
When viewed from the side, 22b, 23a, and 23b have a quadrilateral shape.

24, whose inner periphery is held between central support parts 16a and 16b,
This is a dustproof net whose outer periphery is held between outer periphery supports 20a and 20b.

FIG. 6 shows the operation of the above embodiment, with the solid line showing the stationary state and the broken line showing the upwardly displaced state.

Surface elements 22a, 22b, 23a. By 23b, quadrilateral a
, b, c, and d are constructed, and when the coil bobbin fixed to the central support is displaced upwards, point C displaces the axis of the coil bobbin to point C in the direction, and the quadrilateral atb+ctd is deformed to become quadrilateral a.

b', c', d'.

Point C is displaced in the direction of axis 1, but damper pieces 17b on both sides of damper pieces 17a and 18a are not displaced in the direction perpendicular to axis l.

This is because it is regulated by 18b, 17d, and 18d.

According to the damper of this embodiment, as shown by B in FIG. 2, the damper vibrates with good linearity even at large amplitudes.

In the above embodiment, two damper plates of the same shape are bonded together, but the center support portion and the outer peripheral support portion of one damper plate may be removed.

Further, in the above embodiment, four sets of bendable and extensible rectangular cylinders each having four surface elements are provided, but it is sufficient to provide a rectangular cylinder at each outer periphery of the regular polygonal central support portion.

The present invention has the above configuration, and according to the present invention, it is possible to displace the coil bobbin only in its axial direction, and it is also possible to vibrate with good linearity even when the amplitude is large, and it is possible to reduce the vibration in the large amplitude region. This has the advantage of reducing area distortion.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main parts of a conventional electrodynamic speaker. FIG. 2 is a Kerr displacement characteristic diagram of a conventional electrodynamic speaker damper and a damper according to an embodiment of the present invention, FIG. 3 is a top view of the damper of an electrodynamic speaker according to an embodiment of the present invention, and FIG. The drawings are a view taken along the line A-0-B in FIG. 3, 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, 11... Damper, 12, 13...
...Damper plate, 14a, i4b...-tL, 15
a, 'Isb...Central support section, 16a, 16b.
...Bending portions, 17a to 17d, 18a to 18
a--Damper piece, 19a. 19b...Bending portion, 20a, 20b...
・・Outer periphery support part, 21a, 2lb-bending part,
22a, 22b. 23a, 23b... Surface element, 24... Dustproof net.

Claims (1)

[Scope of Claims] 1. A regular polygonal central support portion having a hole into which a coil bobbin is inserted and fixed, and a plurality of bendable and extensible portions connected to each outer periphery of this central support portion via bending portions. An electrodynamic speaker comprising a damper comprising an outer peripheral support part connected to the outer peripheral part of a rectangular cylinder via a bent part. 2. An electrodynamic speaker according to claim 1, in which reinforcing ribs are formed on the square elements constituting a bendable rectangular cylinder.