JPS5846797A - Speaker with plane diaphragm and its production - Google Patents

Abstract

PURPOSE:To reduce the fraction defective for speaker production, by mounting and fixing an outside diaphragm to a bobbin under the state where a gauge is inserted into the bobbin and inserting an inside diaphragm into a coil bobbin to mount and fix it after pulling out the gause. CONSTITUTION:A diaphragm is preliminarily divided into two, namely, an outside diaphragm 3a and an inside diaphragm 3b on basis of the diameter of a voice coil, and inside faces of the outside diaphragm 3a and a damper 8 are adhered to a voice coil bobbin 5 by an adhesive under the state where a voice coil gauge 7 is inserted between the voice coil bobbin 5 and a pole part 6'. After the adhesive is dried, the voice coil gauge 7 is pulled out from the coil bobbin 5, and the inside diaphragm 3b is inserted into the coil bobbin 5 and is adhered to the outside diaphragm 3a. In this case, since a thin foil 2 whose dimensions are matched to the outside diameter of the outside diaphragm 3a is stuck preliminarily to the upper face of the inside diaphragm 3b, the thin foil 2 is stuck to the upper face of the outside diaphragm 3a by an adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat diaphragm type speaker and a manufacturing method thereof.

In general, planar diaphragm speakers are made using a planar diaphragm that is lightweight and has high bending rigidity, consisting of a low-density foam sandwiched between thin foils with a high specific modulus, and because of its shape, there is little disturbance in sound waves. It has an excellent sound pressure characteristic of two-phase characteristics, but on the other hand, since the vibration surface and the voice coil are installed at right angles, if the rigidity in the vibration direction is insufficient, the diaphragm will bend and the characteristics will deteriorate. . For this reason, a sandwich-structured diaphragm is usually used, in which the density of the core material is reduced, the thickness is increased, the bending rigidity/mass ratio is increased, and both sides of the core material are sandwiched between thin foils to further improve productivity against bending. .

Conventionally, when making a speaker using a flat diaphragm as described above, thin foils 2 and 2' were attached in advance to both the upper and lower surfaces of a core material 1 made of foam, as shown in Fig. 1. An edge 4 is attached to the outer periphery of the diaphragm 3, and a voice coil gauge 7 is placed between the bobbin 5 and the pole portion 6' so that the inner surface of the voice coil bobbin 5 does not come into contact with the ball portion 6' of the yoke 6. In the inserted state, the voice coil bobbin 5 is positioned by the damper 8'4, and then the voice coil gauge 7 is pulled out upward, and the diaphragm 3 is placed from above as shown in FIG.・In a state like '-0'
Glue 9 the upper end of the Secoil bobbin 5 to the lower surface of the diaphragm 3.
At the same time, the outer periphery of the edge 4 is attached to the frame 10.
It was glued to the top section 10' of the. In addition, Figures 1 and 2
In the figure, 11 is a voice coil, 12 is a plate, 1
3 is a magnet.

However, in the above assembly method during speaker manufacturing, it is sometimes necessary to remove the voice coil gauge 7 to install the diaphragm 3, and once the voice coil gauge 7 is removed, the voice fill bobbin 5 is held only by the damper 8. Therefore, when a sideways (horizontal) force 43 is applied to the voice coil bobbin 5 when the diaphragm 3 is attached, the bobbin 5 tilts.
There was a risk that its lower end would come into contact with the ball portion 6' of the yoke 6.

As a result, the speakers produced in this way often emitted abnormal sounds and had a high failure rate.

The present invention has been made in view of these points, and it is an object of the present invention to provide a flat diaphragm type speaker that is relatively easy to manufacture and has a low defective rate, and a method for manufacturing the same.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in the drawings will be described below. In this embodiment, as shown in FIG. 3, the diaphragm 3 is divided in advance into two parts, an outer diaphragm 3a and an inner diaphragm 3b, based on the voice coil diameter, and the voice coil gauge 7 is connected to the voice coil bobbin 5 and the ball portion. 6', the inner surfaces of the outer diaphragm 3a and the damper 8 are bonded to the voice fill bobbin 5 with adhesive. And after the adhesive has dried,
The voice coil gauge 7 is removed from the coil bobbin 5, and then the inner diaphragm 3b is inserted into the coil bobbin 5 as shown in FIG. 4 and bonded to the outer diaphragm 3a. In this case, as shown in FIG. 3, a thin foil 2 having a size matching the outer diameter of the outer diaphragm 3a is pasted on the upper surface of the inner diaphragm 3b. What is necessary is just to stick it on the upper surface of 3a with adhesive.

According to the manufacturing method of the present invention, the diaphragm is divided into two parts, an outer diaphragm and an inner diaphragm, based on the voice coil diameter, as described above,
With the voice coil gauge inserted into the voice coil bobbin, the outer diaphragm is attached and fixed to the voice coil bobbin, and then the voice coil is removed.

After removing the gauge, the inner diaphragm is inserted into the voice coil bottle and fixed.
When the voice coil gauge is removed, the upper end of the voice coil bobbin is securely held not only by the damper but also by the outer diaphragm. Therefore, when the inner diaphragm is installed later, the lower end of the voice fill bobbin is held in place by the ball. There is no contact with other parts, and the defective rate during speaker manufacturing is significantly reduced compared to conventional methods.

Furthermore, according to the planar diaphragm type speaker of the present invention thus completed, although the diaphragm is divided into two parts by the voice coil diameter, the diaphragm is preliminarily attached to the upper surface of the inner diaphragm. Since the thin foil is also attached to the upper surface of the outer diaphragm, no sound pressure level difference occurs between the inner diaphragm and the outer diaphragm. In addition, since the voice coil bobbin is interposed and bonded between the two diaphragms, the adhesion strength between the voice coil bobbin and the diaphragm is sufficient, and there is no breakage during speaker drive, and there is little variation in polarity.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the manufacturing process of a conventional general flat diaphragm type speaker, Fig. 2 is a sectional view of a conventional general flat diaphragm type speaker, and Fig. 3 is a cross sectional view of a flat diaphragm type speaker of the present invention. FIG. 4 is a cross-sectional view showing the manufacturing process. FIG. 4 is a cross-sectional view of one embodiment of the flat diaphragm type speaker of the present invention. 2.2'...Thin foil, 3...Diaphragm, 4...Edge, 5...Voice coil bobbin, 7...Voice coil gauge, 8...Damper, 11...
voice coil. Agent Patent Attorney Aihiko Fukushi Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. Divide the plane diaphragm into two parts, an outer diaphragm and an inner diaphragm, based on the voice coil diameter, and insert the outer diaphragm into the voice coil bobbin with a voice coil gauge inserted into the voice coil bobbin. 1. A method for manufacturing a flat diaphragm type speaker, which comprises: mounting and fixing a voice coil gauge, then removing a voice coil gauge, and then inserting an inner diaphragm into the voice fill bobbin and fixing it there to form a speaker. 2. A flat diaphragm made of a foam core material is divided into two parts, an outer diaphragm and an inner diaphragm, based on the voice coil diameter, and a voice coil bobbin is inserted and fixed between the two diaphragms, and the top surface of both diaphragms is A flat diaphragm type speaker made by pasting a single piece of thin foil.