JPH0732512B2 - Vibration plate for speakers - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plane equivalent diaphragm for a speaker.

Configuration of Conventional Example and Problems Thereof Conventionally, a speaker diaphragm having a cone shape is often used. This is because the cone shape is structurally extremely strong in the vibration direction, and a wide reproduction band can be obtained even if a low elastic material such as paper or plastics is used.

However, a speaker with a large dent, such as a cone,
Depending on the degree, a peak dip was generated on the sound pressure characteristic, which hindered the flatness of the sound pressure frequency characteristic.

In order to solve these problems, in recent years, a high-rigidity planar diaphragm using a honeycomb sandwich structure has been studied and put into practical use.

However, the plane diaphragm requires complicated manufacturing steps such as a honeycomb structure to secure rigidity, and there are many kinds of constituent members, adhesives, etc., so that weight increase and cost increase cannot be avoided.

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

An object of the present invention is to solve the above drawbacks, and to provide a speaker diaphragm for obtaining a speaker with a flat sound pressure frequency characteristic with a simple structure without using a complicated planar diaphragm such as a sandwich structure. It is provided.

According to the present invention, there is provided a first cone-shaped diaphragm formed by forming a rib forming a convex portion protruding on the surface of the diaphragm over the entire circumference of the outer peripheral portion of the diaphragm, and a rib protruding on the back surface side of the diaphragm. A second shallow cone-shaped diaphragm which is formed over the outer peripheral portion of the diaphragm and has a circumferential reinforcing wall formed over the entire circumference at the outer peripheral end of the rib; A third diaphragm that adheres to the peripheral surface, wherein the convex portion of the first cone-shaped diaphragm is located between the adjacent ribs of the second shallow cone-shaped diaphragm to form the second shallow cone-shaped diaphragm. The ribs of the diaphragm are fitted and adhered between the adjacent convex portions of the first cone-shaped diaphragm, respectively, and the first cone-shaped diaphragm, the second shallow cone-shaped diaphragm, and the third vibration Each inner peripheral edge of the plate is adhered to the same voice coil bobbin so that the acoustic radiation surface is substantially flat. As a result, a sound pressure frequency characteristic is flattened, and a low cost and high efficiency speaker can be obtained with a simple configuration.

Description of Embodiments One 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 AA 'in FIG. 1 (a). Is.

In FIG. 1, reference numeral 1 denotes a first cone-shaped diaphragm (hereinafter referred to as a first diaphragm), the outer peripheral portion of which is a valley line 2 and an apex 3 over the entire circumference, and is a projection protruding to the surface of the diaphragm. The rib which forms a part is formed. The inner peripheral edge 4 is bonded to a voice coil (not shown). The straight line connecting the apex 3 and the outermost periphery 5 of the first diaphragm 1 is perpendicular to the vibration direction.

2A is a perspective view of the second shallow cone-shaped diaphragm of the present embodiment, and FIG. 2B is a sectional view taken along the line BB ′ of FIG. 2B.

In FIG. 2, reference numeral 6 denotes a second shallow cone-shaped diaphragm (hereinafter referred to as the second diaphragm), and the vibration formed at points 7, 8, 9, and 10 along the entire circumference of the diaphragm. Ribs protruding on the back surface of the plate, that is, points 7, 9, 10 and points 8, 9, 10 are the vertices 2
It has a rib with two substantially triangular sides. Further, the outermost peripheral portion of the second diaphragm 6 has a ring-shaped flat surface 11 perpendicular to the vibration direction, and the inner peripheral portion of the ring-shaped flat surface 11 has a circumferential direction indicated by diagonal lines. The reinforcing wall 12 is integrally formed with the ring-shaped flat surface 11 and the rib, and the reinforcing wall 12 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 peripheral edge 13 to the reinforcing wall
The section up to 12 is a gentle curve with the point 10 at the top, and a curved cone is formed from the inner peripheral edge 13 to the point 10.

In the first diaphragm 1 and the second diaphragm 6 configured as described above, each apex 3 of the first diaphragm 1 has a point 8 of the second diaphragm 6, a valley line 2 and a point 2. The outer peripheral portion of the first diaphragm 1 is reinforced by fitting and bonding so as to match 7, 9, and the like.

That is, the convex portion of the first cone-shaped diaphragm 1 is between the adjacent ribs of the second shallow cone-shaped diaphragm 6, and the rib of the second shallow cone-shaped diaphragm 6 is the first cone-shaped. The adjacent convex portions of the diaphragm 1 are fitted and adhered to each other. In such a fitted and bonded state, the strength in the radial direction increases, but the strength in the circumferential direction tends to decrease.

Therefore, among the ribs provided on the outer peripheral portion of the second diaphragm 6, the reinforcing wall 12 is integrally provided in the outer peripheral end of the rib that fits into the concave portion of the first diaphragm 1 in the circumferential direction. , Radial direction,
The strength can be increased in the circumferential direction, and the frequency at which bending vibration is generated can be greatly increased to be practically sufficient.

Furthermore, in order to make the acoustic radiation surface as close to a plane as possible, a third diaphragm 15 is arranged on the inner periphery of the second diaphragm 6 as shown in FIG. 3, and the inner peripheral ends of the respective diaphragms are the same. The voice coil bobbin 14 and the dome-shaped center cap 18 are bonded to the tip of the voice coil bobbin 14 to form a substantially flat shape that does not affect the sound pressure frequency characteristics.

FIG. 3 shows the entire structure of this embodiment. FIG. 3 (a) is an external perspective view thereof, and FIG. 3 (b) is FIG. 3 (a).
6 is a cross-sectional view taken along the line CC ′ of FIG.

In FIG. 3, as described above, the outer peripheral portions of the first diaphragm 1 and the second diaphragm 6 are fitted and adhered to each other, and the inner peripheral ends of the first diaphragm 1 and the second diaphragm 6 are adhered to different positions on the abdomen of the voice coil bobbin 14. ing. 15 is a ring-shaped third diaphragm,
The outer periphery thereof is adhered to the inner peripheral surface 16 of the second diaphragm 6, and the inner periphery thereof is adhered to the tip portion 17 of the voice coil bobbin 14. Reference numeral 18 denotes a dome-shaped center cap that is attached to the tip of the voice coil bobbin 14. The acoustic radiation surface obtained in this way is substantially flat, and the sound pressure frequency characteristics can be made flat.

As described above, according to the present embodiment, a plurality of diaphragms having different heights and diameters are sequentially stacked in order of increasing size so that the acoustic radiation surface becomes a substantially flat surface that does not affect the sound pressure frequency characteristics. However, the high-frequency reproduction frequency can be obtained only about 1/3 or less of the conventional example only by stacking a simple cone-shaped diaphragm, but in the structure as described above, the bending vibration is generated at the lowest frequency. The sound pressure frequency characteristics can be flattened by fitting and adhering the joint portion of the diaphragm and the second diaphragm so as to reinforce the acoustic radiation surface. Furthermore, the structure is simple and the weight can be reduced, and a low cost and highly efficient speaker can be obtained.

EFFECTS OF THE INVENTION As described above, the present invention provides a substantially flat acoustic radiation surface by stacking a plurality of diaphragms together with the first and second
With a structure in which the joint portion of the diaphragm is reinforced in the radial direction and the circumferential direction, it is possible to provide a speaker having a flat sound pressure frequency characteristic and a wide reproduction frequency band. Further, as compared with the conventional example, the manufacturing is simple and the weight is reduced, and a low cost and highly efficient speaker can be provided, and its effect is great.

[Brief description of drawings]

FIG. 1A is an external perspective view of a first cone-shaped diaphragm of a speaker diaphragm according to an embodiment of the present invention.
1B is a sectional view taken along the line AA 'of FIG. 1A, FIG. 2A is an external perspective view of the second shallow cone-shaped diaphragm, and FIG. 2 (a) is a sectional view taken along line BB ', FIG. 3 (a) is an external perspective view of the same embodiment, and FIG. 3 (b) is a third view.
It is the CC 'sectional view taken on the line of FIG. 1 ... 1st cone-shaped diaphragm, 6 ... 2nd shallow cone-shaped diaphragm, 12 ... Reinforcing wall, 14 ... Voice coil bobbin,
15 …… Third diaphragm, 18 …… Dome-shaped center cap.

Claims (1)

[Claims] 1. A rib forming a convex portion projecting on the surface of a diaphragm,
The first cone-shaped diaphragm formed over the entire circumference of the diaphragm and the ribs protruding to the back side of the diaphragm are formed over the entire circumference of the diaphragm and the circumference of the outer circumference of the rib is rounded. A second shallow cone-shaped diaphragm having a reinforcing wall extending in the entire direction, and a third diaphragm bonded to the inner peripheral surface of the second shallow cone-shaped diaphragm. The convex portion of the second cone-shaped diaphragm is located between the adjacent ribs of the second shallow cone-shaped diaphragm, and the rib of the second shallow cone-shaped diaphragm is the first rib.
Of the first cone-shaped diaphragm, the second shallow cone-shaped diaphragm and the third diaphragm while being fitted and bonded between the adjacent convex portions of the cone-shaped diaphragm of FIG. A diaphragm for a speaker, characterized in that the sound emitting surface is adhered to the same voice coil bobbin and has a substantially flat sound emitting surface.