JPH04326297A - Speaker - Google Patents

Abstract

PURPOSE:To provide the speaker to reduce the peak and dip of a partial divided resonance area near a high-frequency limit frequency for a frequency characteristic and improving sound quality in a flat frequency characteristic at the speaker used for various electric equipments. CONSTITUTION:For the constitution of a part sticking the outer periphery of a corn part 30a constituting a circular diaphragm 30 and the inner periphery of an edge part 30b, a wide sticking part 30c and a narrow sticking part 30d are provided, and the diaphragm alternately arranging them in the circumferential direction.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker whose diaphragm has a circular outer shape.

0002

[Prior Art] Flattening of speaker frequency characteristics has traditionally been one of the important considerations in design, but today, with the progress of digitalization of circuits, including in the audio video market, high sound quality with flatter characteristics has been achieved. required of speakers.

[0003] A conventional speaker will be explained below. FIG. 6 shows the structure of a conventional speaker. Figure 7
shows a plan view of a diaphragm used in a conventional speaker,
FIG. 8 shows a cross-sectional shape cut in an arbitrary direction on a plane passing through the central axis of the diaphragm. In FIG. 6, a ring-shaped magnet 2 and a top plate 3 are arranged on a bottom plate 1 having a cylindrical center pole 1a at the center, and a magnetic air gap is created between the inner periphery of the top plate 3 and the center pole 1a of the bottom plate 1. form 4. Top plate 3
A frame 5 is joined to the top, and a winding portion of a voice coil 6 is fixed to the frame 5 via a damper 7 so as to be located at the center of the magnetic gap 4. Further, the cylindrical bobbin of the voice coil 6 and the central through hole of the diaphragm 8 are bonded together, and the edge portion of the diaphragm 8 is bonded and fixed to the frame 5. 9 is a canceling magnet, 10 is a shield cover, and 11 is a dust cap.

The operating principle of the speaker constructed as described above will be explained below. When electrical input is applied to the voice coil 6 located in the center of the magnetic air gap 4 in a parallel magnetic field, it generates a force in the vertical direction according to Fleming's left hand rule. The force is transmitted from the voice coil 6 to the diaphragm 8 via the cylindrical bobbin. The diaphragm 8 vibrates the air in front of it to generate sound.

The structure and shape of the diaphragm 8 are as shown in the plan view of FIG. 7, and a cross section cut in an arbitrary direction along a plane passing through the central axis of the diaphragm 8 is shown in FIG. As shown in FIG. 6, the conventional diaphragm 8 has a cone portion 8a and an edge portion 8b.
The bonded portions 8c have the same circumferential dimensions and are bonded and bonded together so as to form concentric circles in a circular shape. Therefore, when the diaphragm 8 is cut on all planes passing through the central axis of the through hole, the cross-sectional shape is the same.

[0006]

[Problem to be Solved by the Invention] With the above-mentioned configuration, in the conventional speaker, the axisymmetric modes become equal in the divided resonance region near the high-frequency limit frequency due to the frequency characteristics, and peaks and dips in the frequency characteristics are reduced. occurs more markedly. Then, flatness is determined by changing the dimensions and shapes of the cone portion 8a and edge portion 8b, or by varying the detailed specifications (material, molding conditions, etc.) in the molding process of the cone portion 8a. was. However, the former involved mold costs, and the latter had little effect.

[0007]

[Means for Solving the Problems] In order to solve this problem, the speaker of the present invention has a structure in which the outer periphery of the cone portion and the inner periphery of the edge portion of the circular diaphragm are bonded together.
The structure is such that a wide bonded portion and a narrow bonded portion are provided, and these are arranged alternately in the circumferential direction.

[0008]

[Function] With this diaphragm structure, compared to a conventional diaphragm in which the cone part and edge part are bonded with an even width around the entire circumference, the frequency characteristics of the diaphragm allow for split resonance near the high-frequency limit frequency. Peaks and dips in the region become smaller, resulting in flatter frequency characteristics. This is because when the diaphragm resonates, the resonance sharpness of peaks and dips in the frequency characteristics is alleviated by providing non-uniform mass and internal loss around the outer periphery of the cone portion.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a half-sectional view showing an embodiment of the speaker of the present invention, FIG. 2 is a rear view of the diaphragm, and FIGS. 3 and 4 are sectional views of essential parts of the diaphragm.

In FIG. 1, 21 is a bottom plate having a center pole 22 in the center, 23 is a magnet on a ring placed on this bottom plate 21, 24 is a top plate placed on this magnet 23, 2
5 is a cancellation magnet arranged on the bottom surface of the bottom plate 21, 26 is a shield cover placed over these, 27 is a magnetic circuit constituted by these, 28 is a magnetic gap formed by this magnetic circuit 27, and 29 is a A frame 30 is connected to the upper part of the magnetic circuit 27, a circular diaphragm 30 has its periphery connected to the periphery of the frame 29, and 31 is connected to the center of the diaphragm 30, eccentric to the magnetic gap 28. 32 is a damper that supports the middle portion of the voice coil 31, and 33 is a dust cap coupled to the upper end surface of the voice coil 31.

As shown in FIG. 2, the diaphragm 30 is composed of a cone portion 30a and an edge portion 30b.
A wide bonding portion 30c as a bonding portion with the cone portion 30a on the inner peripheral portion of b, and a wide bonding portion 3
0d are arranged alternately in the circumferential direction.

FIGS. 3 and 4 show cross sections of the wide bonded portion 30c and the narrow bonded portion 30d.

As shown in FIGS. 3 and 4, the cone portion 3
Since the bonding width dimension and area of the edge portion 30b at the outer periphery of 0a are set unevenly in the circumferential direction, each resonance mode becomes unbalanced and occurs near the high frequency limit frequency and in the divided resonance region. The resonance sharpness of the multiple peaks and dips that had previously existed is relaxed, and a flatter sound pressure frequency characteristic is obtained.

FIG. 5 shows a comparison of the sound pressure frequency characteristics of a speaker using the diaphragm 30 according to this embodiment and a speaker using a conventional diaphragm shape. As is clear from FIG. 5, the speaker according to this embodiment has a remarkable effect in flattening the sound pressure frequency characteristics in the divided resonance regions.

[0016]

As described above, the present invention provides a speaker using a circular diaphragm, in which the structure of the bonded portion between the outer periphery of the cone portion and the inner periphery of the edge portion constituting the circular diaphragm is a wide bonded portion. By constructing a speaker using a diaphragm having a shape in which a narrow bonded part and a narrow bonded part are arranged alternately in the circumferential direction, the conventional diaphragm production process can be used as is. This makes it possible to realize a speaker with flatter sound pressure frequency characteristics without increasing material costs.

[Brief explanation of drawings]

FIG. 1 is a half-sectional view showing the structure of a speaker in an embodiment of the present invention.

[Figure 2] Rear view of the diaphragm in the same example

[Fig. 3] A cross-sectional view of the diaphragm in the same example in the A-O direction in Fig. 2

[Figure 4] Cross-sectional view in the B-O direction of Figure 2

[Figure 5] Sound pressure frequency characteristic diagram of the present invention and conventional speakers

[
FIG. 6 is a half-sectional view showing the structure of a speaker in a conventional embodiment.

[Figure 7] Rear view of the speaker diaphragm in the conventional example

[Figure 8
] Cross-sectional view of a conventional speaker diaphragm in the A-O direction

[Explanation of symbols]

27 Magnetic circuit 28 Magnetic gap 29 Frame 30 Diaphragm 30a Cone part 30b Edge part 30c Wide bonding part 30d Narrow bonding part 31 Voice coil

Claims (1)

[Claims] Claim 1: In a speaker using a circular diaphragm, the configuration of the bonded portion between the outer circumference of the cone portion and the inner circumference of the edge portion constituting the circular diaphragm includes a wide bonded portion and a narrow bonded portion. A speaker using a diaphragm characterized by having mating portions arranged alternately in the circumferential direction.