JPS60199297A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To smoothen a sound pressure frequency characteristic, to widen a reproduction frequency band and to facilitate production by obtaining an approximately plane acoustic radial surface by overlapping plural diaphragms and by reinforcing joints of the 1st and the 2nd diaphragms in diameter and circumference directions. CONSTITUTION:An uneven part in the radial direction of an outer circumference of the 1st conical diaphragm 1 is formed by a line 2 and a top 3, and a straight line connecting the top 3 to the most-outer circumference 5 is made vertical with respect to the vibration direction. An outer circumference of the 2nd shallow conical diaphragm 6 has a rib formed by points 7, 8, 9 and 10, while the most-outer circumference includes a ring-shaped plane 11 vertical in the vibration direction. In an inner circumference of the plane 11 a reinforcement wall 12 in the circumference direction is formed into a solid construction with the plane 11 and said rib, and made parallel in the vibration direction. A curved cone is formed from an inner circumference end 13 to the point 10. Both diaphragms are fitted and glued so that the top 3 and a trough line 2 can be coincident with the point 8 and a group of the points 7, 9, etc., respectively, and the most-outer circumference of the diaphragm 1 is reinforced. The strength of the reinforcement wall 12 is increased in both radius and circumference directions, and the frequency generating bending vibration is substantially raised.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a planar equivalent type speaker diaphragm.

Conventional Structure and Problems Conventionally, a cone-shaped diaphragm for a speaker has often been used. This is because the cone shape has extremely high structural strength in the vibration direction, and a wide reproduction band can be obtained even when using low elasticity materials such as paper and plastics.

However, speakers with a large concave shape, such as a cone,
Depending on the extent of this, a peak dip occurs in the sound pressure characteristics, which interferes with the flatness of the sound pressure frequency characteristics.

In order to solve these problems, in recent years, a highly rigid planar diaphragm using a two-cam sandwich structure has been studied and put into practical use.

However, planar diaphragms require complex manufacturing processes such as a non-uniform structure to ensure rigidity, and there are many types of component parts and adhesives, so increased weight and cost are unavoidable. be.

Therefore, there has been a desire for a method that achieves flatness of sound pressure frequency characteristics at low cost.

Purpose of the Invention The present invention solves the above-mentioned drawbacks, and provides a speaker diaphragm for obtaining a speaker with a flat sound pressure frequency characteristic with a simple structure without using a complex planar diaphragm such as a sandwich structure. This is what we provide.

Structure of the Invention The present invention includes a first cone-shaped diaphragm having a radially uneven portion on its outer periphery, a radial lip on its outer periphery, and
A second shallow diaphragm that is fitted and bonded to the concave and convex portion of the first cone-shaped diaphragm and has a circumferential reinforcing wall at the outer peripheral end of the lip that fits into the concave portion of the first cone-shaped diaphragm. the first cone-shaped diaphragm;
The inner circumferential ends of the second shallow cone-shaped diaphragm and the third diaphragm are bonded to the same voice coil bobbin so that the sound radiation surface is substantially flat, thereby reducing the sound pressure. A low-cost, high-efficiency speaker with flat frequency characteristics and a simple configuration can be obtained.

Description of examples An embodiment of the present invention will be described below.

FIG. 1(a) is a perspective view of a first cone-shaped diaphragm of a speaker diaphragm according to an embodiment of the present invention, and FIG. 1(b) is a sectional view taken along the line A-A in FIG. 1(a). It is.

In Fig. 1, reference numeral 1 denotes a first cone-shaped diaphragm (hereinafter referred to as the first diaphragm), and its outer periphery forms an uneven portion in the radial direction with valley lines 2 and apexes 3. There is. 4
A voice coil (not shown) is bonded to the inner circumferential edge. Note that the straight line connecting the apex 3 and the outermost circumference 6 of the first diaphragm 1 is perpendicular to the vibration direction.

FIG. 2(,) is a perspective view of the second shallow cone-shaped diaphragm of this embodiment, and FIG. 2 Φ) is a sectional view taken along the line B-Er of FIG. 2 Φ).

In FIG. 2, 6 is a second shallow cone-shaped diaphragm (hereinafter referred to as the second diaphragm), and points 7, 8,
It has a lip formed by 9.10, that is, a lip whose two sides are two substantially triangular faces whose vertices are points 7 and 8.10 and points 8 and 9.10. Further, the outermost periphery of the second diaphragm 6 has a ring-shaped flat surface 11 perpendicular to the vibration direction, and the inner periphery of the ring-shaped flat surface 11 has a circumferential direction indicated by diagonal lines. The reinforcing wall 12 is a ring-shaped flat surface 11,
The reinforcing wall 12 is formed integrally with the lip and is parallel to the vibration direction. Further, 13 is bonded to a voice coil (not shown) at the inner peripheral end. In addition, from the inner circumferential end 13 to the reinforcing wall 12
The cross-section at the same angle is a gentle curve with the apex at point 1°, and from the inner circumferential end 13 to point 10 forms a curved cone.

The first diaphragm 1 and the second diaphragm 6 configured as described above have each vertex 3 of the first diaphragm 1 connected to the point 8 of the second diaphragm 6 and the valley line 2 to the point. The outermost periphery of the first diaphragm 1 is reinforced.

That is, the uneven portion provided on the outer circumference of the first diaphragm 1 and the lip of the second diaphragm 6 are fitted and bonded to each other. In this fitted and bonded state, the strength in the radial direction increases, but the strength in the circumferential direction tends to decrease.

Therefore, among the lips provided on the outer periphery of the second diaphragm 6, a reinforcing wall 12 is integrally provided in the circumferential direction at the outer periphery end of the lip that fits into the recess of the first diaphragm 1. The strength can be increased in both the radial direction and the circumferential direction, and the frequency at which bending vibration occurs can be significantly raised to a level sufficient for practical use.

Furthermore, in order to make the sound radiation surface as close to a flat surface as possible, a third diaphragm 16 is placed on the inner periphery of the second diaphragm 6 as shown in FIG. By adhering the dome-shaped center cap 18 to the voice coil bobbin 14 and adhering the dome-shaped center cap 18 to the tip of the voice coil bobbin 14, it is made into a substantially planar shape that does not affect the sound pressure frequency characteristics.

Figure 3 shows the overall configuration of this embodiment.
) is a perspective view of the external appearance, and Fig. 3(b) is C in Fig. 3(a).
-C' line sectional view.

In FIG. 3, as described above, the outer circumferential parts of the first diaphragm 1 and the second diaphragm 6 are fitted and bonded together, and the inner circumferential ends of each are bonded to different positions on the abdomen of the voice coil bobbin 14. ing. Reference numeral 16 denotes a ring-shaped third diaphragm, whose outer periphery is bonded to the inner circumferential surface 16 of the second diaphragm 6, and whose inner periphery is bonded to the tip 17 of the voice coil bobbin 14. 18 is the tip I of the voice coil bobbin 14
It is a dome-shaped center cap that is attached by C. The acoustic radiation surface obtained in this manner has a substantially planar shape, and can have a flat sound pressure frequency characteristic.

As described above, according to this embodiment, a plurality of diaphragms with different heights and diameters are stacked one on top of the other in order from the largest one to make the sound radiation surface a substantially flat surface that does not affect the sound pressure frequency characteristics. However, by simply stacking simple cone-shaped diaphragms, the high-frequency reproduction frequency can only be obtained below the level of the conventional example. By fitting and adhering the diaphragm and the second diaphragm so as to reinforce the joint, the sound radiation surface can be made substantially flat, and the sound pressure frequency characteristic can be made flat. Sara K,
The structure is simple and lightweight, and a high-efficiency speaker can be obtained at low cost.

Effects of the Invention As described above, the present invention obtains a substantially flat acoustic radiation surface by overlapping a plurality of diaphragms, and also provides a first and a second diaphragm.
By adopting a structure in which the joints of the diaphragms are reinforced in the radial and circumferential directions, it is possible to provide a speaker with flat sound pressure frequency characteristics and a wide reproduction frequency band. Moreover, compared to the conventional example, the manufacturing is simple and the weight is reduced, and a high-efficiency speaker can be provided at low cost, which is highly effective.

[Brief explanation of drawings]

FIG. 1(a) is an external perspective view of a first cone-shaped diaphragm of the speaker diaphragms in an embodiment of the present invention;
Figure Φ) tit is a sectional view taken along the line A-A' in Figure 1 (,), Figure 2 (a) is an external perspective view of the second shallow cone-shaped diaphragm, Figure 2 (b) is the second B-B' line sectional view of figure (,), 3rd
Figure (&) is an external perspective view of the same embodiment, and Figure 3 (b) is a sectional view taken along the line CC' of Figure 3 (,). DESCRIPTION OF SYMBOLS 1...First cone-shaped diaphragm, 6...Second shallow cone-shaped diaphragm, 12...Reinforcement wall, 1
4...Voice coil bobbin, 16...3rd
diaphragm, 18... dome-shaped center cap.

Claims (1)

[Claims] A first cone-shaped diaphragm having an uneven portion in the radial direction on the outer periphery, and a radial lip on the outer periphery, which is fitted and bonded to the uneven portion of the first cone-shaped diaphragm. ,
a second shallow cone-shaped diaphragm having a circumferential reinforcing wall at the outer peripheral end of a rib that fits into the four parts of the first cone-shaped diaphragm; and an inner surface of the second shallow cone-shaped diaphragm. a third diaphragm adhered to a peripheral surface, the inner peripheral ends of the first cone-shaped diaphragm, the second shallow cone-shaped diaphragm, and the third diaphragm having the same voice. A speaker diaphragm that is bonded to a coil bobbin and has a substantially flat acoustic radiation surface.