JPS5983497A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To manufacture simply a thin plate, by constituting the thin plate having many hollow projections whose bottom of the projection is punched out, and a surface member. CONSTITUTION:The thin plate 3 has the hollow cylindrical projections 2, which are arranged uniformly in the circumference direction in the concentric form to the center of the diaphragm and are incorporated with the thin plate. Further, the bottom of the projections 2 are punched out. The thin plate 3 is made of metallic sheet such as aluminum or titanium sheet, of plastic sheet such as polypropylene or carbon fiber reinforced polypropylene. Since the diaphragm is formed in multi-layered structure, the bending rigidity is large according to the principles of sandwich construction, and the E/rho (Young's modulus/density) is the same value as that of a conventional honeycomb diaphragm. Since the projections are arranged in concentric form and uniformly in the circumferential direction, the bending rigidity near the circumference of the diaphragm is made uniform and increased and the bending rigidity of the entire diaphragm is made uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lightweight and highly rigid speaker diaphragm.

A diaphragm for a speaker is required to be light, have a large ratio of Young's modulus to density (hereinafter referred to as w/p), and be even thicker. There was a honeycomb diaphragm with a sandwich structure, such as No. 187, whose core material was a honeycomb core with a hexagonal cell shape, and the front and back sides of this tragedy were attached.

However, with this honeycomb diaphragm, the manufacturing method of the honeycomb core, which is the core material, is complicated and expensive, and the surface material is divided into hexagonal shapes evenly by the honeycomb core, so one surface material is the cell of each honeycomb core. A phenomenon in which parts vibrate (hereinafter referred to as cell resonance) occurs concentrated at a specific frequency, narrowing the frequency band of the sound pressure characteristics radiated from the diaphragm.

This invention eliminates the drawbacks of the conventional ones as described above, and at the same time provides a lightweight, low-cost, high-performance speaker diaphragm. A diaphragm for a speaker comprising a thin plate having a large number of hollow protrusions uniformly arranged in the circumferential direction and a hole in the bottom of the protrusion, and a surface material attached to the protrusion side of the thin plate. .

This invention consists of a thin plate with hollow protrusions and a surface material pasted on the protrusion side of the thin plate, so it can be manufactured more easily than a honeycomb diaphragm, and is low cost and lagging behind in mass production. It is lightweight because it is composed of two thin plates.

Since the protrusions are arranged concentrically and uniformly in the circumferential direction with λ1 at the center of the diaphragm, the bending rigidity near the 0-periphery end is uniform and large, and the bending rigidity over the entire surface of the diaphragm is uniform, resulting in high performance. Because the surface material that serves as the vibration QL plate for speakers is not structured to be uniformly divided by the honeycomb core, vibrations do not occur in the cell part due to concentration at a constant frequency of 9%, and deterioration of sound pressure characteristics is also significantly improved. It is something.

The details of this invention will be further explained below with reference to the illustrated embodiments.

FIG. 1 is a partially cutaway plan view of the surface material of a speaker diaphragm showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view of FIG. In these figures, (1)
is a surface material, (3) is a thin plate having hollow cylindrical protrusions (2), and these protrusions (2) are concentric with the center of the diaphragm and are uniformly arranged in the circumferential direction. It is integrated with (3). Further, the bottom ff1r+ portion of the projection (2) is a punched hole.

The material used for the thin plate (3) is a metal sheet such as aluminum or titanium, or a sheet of plastic such as polypropylene, polyenalene, polycarbonate, or carbon reinforced dark blue polypropylene.9 The surface material (1) is also a thin plate (3). ), metal sheets, plastic sheets, or even reinforced paper sheets made by mixing paper with plastic should be used.

The surface material (1) is pasted on the tip surface of the cylindrical projection (2) of the thin plate (3) using a polyamide-based or EOA-based adhesive.

Next, the manufacturing method will be described. The metal or plastic sheet mentioned above is formed into a thin plate (
After molding 3), the tip of the protrusion (2) is slightly cut to open the protrusion (2). After this, glue the surface side (1) of the sheet made of the above-mentioned old family with the projections (2).
) A diaphragm can be manufactured by pasting it on the tip surface of the diaphragm.

Since the speaker diaphragm constructed as described above has a multilayer structure, it has a high rigidity for one song due to the sandwich structure principle, and the E//p is equivalent to that of a conventional honeycomb diaphragm (to obtain irj). ) Since the projections (2) are arranged concentrically and uniformly in the circumferential direction, the bending rigidity near the peripheral edge of the diaphragm can be made uniform and large, and the entire surface of the diaphragm can be The bending stiffness of is equalized.

Focusing on the vibration v1 form of the surface material (), it has a structure in which 21 protrusions (21 parts) are joined to the surface phase (1) as shown in Figure 1, so it is divided uniformly like a conventional honeycomb diaphragm. Since the vibration is not concentrated at a constant frequency of 9%, vibrations in the cell section do not occur, and there is little deterioration in sound pressure characteristics.

Further, the projections (2) on the auxiliary plate (3) can be simply formed by the molding method as described above.

In the above embodiment, the shape of the protrusion is circular, but the shape is not limited to a circle, but may be a polygonal structure such as a quadrangle or a pentagon, and the same effect can be obtained. In addition, although the end face of the protrusion (2) is shown as an example, the protrusion (2)
Of course, the end face may be closed. This will not only eliminate the cutting process, but will also make the process of attaching the protrusion (21) and the surface material (1) easier, although the M1 depth will increase slightly.

Further, the shape of the diaphragm may be a cone shape, a dome shape, a flat plate, etc.

As described above, according to the present invention, the protrusions have a large number of hollow protrusions, and the protrusions are composed of a thin plate with a hole in the bottom and a surface material, and furthermore, the protrusions are concentric with the center. Since the structure is such that they are arranged uniformly in the circumferential direction, thin plates can be easily manufactured and costs can be reduced. Moreover, since it is composed of two sheets, it is lightweight, and the bending rigidity near the peripheral edge of the diaphragm is uniform and large, and the diaphragm for a speaker has uniform bending rigidity over the entire surface of the diaphragm.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway plan view showing an embodiment of the present invention, and Fig. 2 is a sectional view taken along the line ■-■ of Fig. 1.

Claims (1)

[Claims] Hollow protrusions that are concentric with the center, uniform in the circumferential direction, and arranged over the entire surface are integrally formed, and the bottom of the protrusions is made into a hole, and the thin plate is attached to the tip of the protrusion. A diaphragm for a speaker, characterized in that it is constituted by a structure made of a surface material coated with a surface material.