JPS6042679B2 - speaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speaker that dynamically utilizes air compliance, and particularly to a speaker that can obtain linear compliance with respect to vibration amplitude.

The applicant previously proposed a speaker in which an air damper is configured as shown in FIG. 1, and the compliance of this air damper is dynamically utilized.

In FIG. 1, 1 is a center pole, 2 is a magnet, 3 is a plate, 4 is a voice coil bobbin, 5 is a voice coil wound around the bobbin 4, 6 is a damper, 7 is a frame, and 8 is an edge 9 connected to the frame 4. 10 is a damper that connects the diaphragm 8 and the bobbin 4; 11 is a diaphragm attached to the diaphragm;
12 is a lid that seals the upper end of the bobbin 4, and 12 is a dust cap. With this configuration, the diaphragm 8 and the damper 11
The air in the part A surrounded by the lid 11 and the dust cap 12 will no longer leak to the outside, and the air in this part A will flow into the bobbin 4.
It undergoes compression and expansion as the vibrations occur, and the resulting compliance allows it to function as a type of mechanical filter. However, in this case, the damper 10 is used to connect the bobbin 4 and the diaphragm 8, and since this damper 10 is generally soft, the vibration of the damper 10 due to the vibration of the bobbin 4 is caused by the solid line in Figure 3. As a result, the ideal state shown by the broken line in FIG. 3 becomes distorted.
For this reason, there is a problem that distorted sound is generated due to the distortion of the damper 10, and there is also a problem that the fatigue of the damper 10 increases because the amplitude increases by the amount of distortion. Additionally, when designing a speaker with such an air damper, its compliance C is generally C=-...
(1) However, the design is performed assuming that the following relationship is satisfied: V: Air volume of the enclosed part A ρ: Air density c: Sound speed S: Effective vibration aperture. Compliance C is (1)
There is a problem that the relationship is not as simple as the formula, which makes it difficult to design.

The present invention provides a speaker that solves these conventional problems.

An embodiment of the present invention will be described below with reference to FIG.

Components in FIG. 2 having the same functions as those in FIG. 1 are given the same reference numerals and their explanations will be omitted. Reference numeral 13 denotes a sub-diaphragm whose inner periphery is fixed to the outer periphery of the bobbin 4 and whose outer periphery is attached to the main diaphragm 8 via an elastic body 14 such as an edge, rubber, corrugation edge, or the like. With this configuration, since the sub-diaphragm 13 is harder than the conventional damper 10, the strain caused by the vibration of the bobbin 4 is reduced.Moreover, by reducing the area of the elastic body 14, the elasticity can be increased compared to the conventional damper 10. Since the surface area is smaller, fatigue is also reduced.

In addition, the air compliance also shows a linear characteristic with respect to the vibration amplitude and can be calculated using equation (1), making the design easier. As described above, according to the present invention, the air compliance can be changed linearly with respect to the vibration amplitude, so that the distortion of the elastic portion can be suppressed, fatigue can be reduced, and the design can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional example, FIG. 2 is a sectional view of an embodiment of the present invention, and FIG. 3 is a diagram showing vibration modes of the conventional example.

Claims (1)

[Claims] 1. Sealing the tip of the bobbin, and attaching the sub diaphragm whose inner periphery is attached to the bobbin to the main diaphragm via an elastic body, covering the bobbin, the main diaphragm, the auxiliary diaphragm and the elastic body. A speaker characterized by a part surrounded by a dust cap that prevents air from leaking to the outside.