JPH10276496A - Speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speaker with a simple structure which suppresses the rolling of a diaphragm. SOLUTION: A drive mechanism 9 and a main damper mechanism 90 are connected to the central part of a diaphragm 3. Two sub damper mechanisms 91 are also connected to the diaphragm 3 on both sides in the longitudinal direction of the diaphragm 3 centered on the mechanism 9. Here, the distance A from the mechanism 9 to the left sub damper mechanism 91 and the distance B from the mechanism 9 to the right sub damper mechanism 90 are set to different values.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker for driving a flat diaphragm at a central portion to convert an electric signal into sound.

[0002]

2. Description of the Related Art In recent years, a thin speaker as shown in FIG. 3 has been developed in order to cope with an increase in size and thickness of a television receiver. As shown in the figure, in this speaker, a flat frame is formed by joining a frame (1) and a flat base plate (10) having a large opening at the center. The frame (1) and the base plate (10)
May be integrally formed. A strip-shaped diaphragm (3) is connected to an opening of the base plate (10) via a ring-shaped edge (2) made of an elastic material such as urethane foam or rubber.

[0003] A driving mechanism (9) and a main damper mechanism (90) having a configuration described later are connected to the center of the diaphragm (3). Circular openings (12) and (31) are formed in the center of the frame (1) and the diaphragm (3), respectively, and both ends are opened on the inner peripheral surface of the opening (31) of the diaphragm (3). The upper end of the cylindrical voice coil bobbin (5) is adhesively fixed. On the other hand, the lower end of the voice coil bobbin (5) passes through the opening (12) of the frame (1) with a margin.

[0004] At the upper end opening of the voice coil bobbin (5),
Cap to protect the magnetic circuit described below from dust and dirt
(8) is fitted. A voice coil (50) is wound around the outer peripheral surface of the lower end of the voice coil bobbin (5).

A voice coil (5) is provided on the back of the frame (1).
A ring-shaped upper plate (41) is fixed so as to surround 0), and a ring-shaped gap G is formed between the voice coil (50) and the inner peripheral surface of the upper plate (41). On the back of the upper plate (41), a ring-shaped main magnet
(42) is fixed. A convex bottom plate (43) is fixed to the back of the main magnet (42).
The bottom plate (43) has a round shaft (43
a), and the round shaft portion (43a) penetrates into the voice coil bobbin (5). The upper plate (41), the main magnet (42), the bottom plate (43), and the gap G form a magnetic circuit through which the magnetic flux from the voice coil (50) flows.

On the back surface of the bottom plate (43), a ring-shaped cancel magnet (44) having a polarity opposite to that of the main magnet (42) is arranged to prevent generation of magnetic flux leakage. Then, a shield cover (4) is attached to the back surface of the frame (1) so as to cover the upper plate (41), the main magnet (42), the bottom plate (43), and the cancel magnet (44). Thus, a driving mechanism (9) for reciprocatingly driving the diaphragm (3) is configured.

The outer peripheral surface of the voice coil bobbin (5)
It is connected to the back surface of the diaphragm (3) via a coupling cone (6) and to the inner surface of the frame (1) via a main damper (7) made of cloth. Thus the diaphragm
A damper mechanism (90) for supporting the central portion of (3) with a damper is configured.

In the above speaker, the magnetic flux generated from the main magnet (42) is guided to the upper plate (41) and the bottom plate (43) and is focused on the gap G, whereby a magnetic field is generated in the gap G. I do. Therefore, the voice coil (50) is supplied with the
(50) generates an electromagnetic force according to Fleming's left-hand rule. As a result, the diaphragm (3) vibrates integrally with the voice coil (50) and the voice coil bobbin (5), and the electric signal is converted into sound.

[0009]

However, in the above loudspeaker, the diaphragm (3) has a strip shape whose longitudinal length is much larger than the diameter of the diaphragm of the conventional cone type loudspeaker. The diaphragm (3) is driven by damper support at only one point in the center,
Large rolling occurs in (3). As a result, when an electric signal is converted into sound, a large loss occurs and a high sound pressure cannot be obtained. Further, the voice coil (50) may come into contact with the inner peripheral surface of the upper plate (41) and generate abnormal noise. In order to suppress the rolling of the diaphragm (3), there has been proposed a speaker of a multi-point driving and multi-point supporting type in which the diaphragm is driven at a plurality of points and each driving point is damped (see Japanese Patent Application Laid-Open No. H08-1996). 154296 [H04R 9/06])
However, the speaker has a problem that the structure is complicated because a plurality of drive mechanisms must be provided. An object of the present invention is to provide a speaker having a simple structure that can effectively suppress rolling of a diaphragm.

[0010]

A speaker according to the present invention comprises:
A plate-shaped diaphragm, a single drive mechanism that is connected to the diaphragm at the center of the diaphragm, and drives the diaphragm back and forth according to an input signal, and diaphragms at multiple positions around the drive mechanism And a plurality of damper mechanisms for damper-supporting the diaphragm, wherein the diaphragm is driven by the single drive mechanism. Specifically, a main damper mechanism for damper-supporting the diaphragm is connected to the center of the diaphragm to which the drive mechanism is connected.

In the speaker, the diaphragm is driven by a single driving mechanism connected to the center of the diaphragm.
Here, the flat diaphragm is damped by the damper mechanism at a plurality of points, so that rolling is effectively suppressed. Further, since the diaphragm is driven by a single drive mechanism, the structure is simpler than that of a conventional speaker having a plurality of drive mechanisms.

More specifically, the plurality of damper mechanisms are connected to the diaphragm at a plurality of asymmetric positions about the connection point of the drive mechanism.

The vibration of the diaphragm includes a plurality of modes that cause the diaphragm to undulate, and the positions of the antinodes and nodes differ for each mode. In order to effectively suppress the swell, it is desirable to always support the position of the belly with a damper. However,
In some modes, the position of the belly may be the position of the node in other modes. Therefore, in a configuration in which a plurality of symmetric positions about the driving point are supported by the damper, a certain 1
In one mode, when those support points are located at the antinode position, an effective swelling suppression effect can be obtained, but in the other modes, all of those support points are at or near the knot position, which is effective. There is a possibility that the effect of suppressing the undulation cannot be obtained. Therefore, as in the above specific configuration, by disposing a plurality of damper mechanisms at a plurality of asymmetrical positions around the connection point of the drive mechanism, one or a plurality of support points can be located at antinode positions in one mode. Alternatively, when the mode is changed and the position of the antinode is shifted in a case where the position near the position is supported, there is a high possibility that another one or a plurality of support points exist at the shifted position. Is suppressed by the support points. Like this
In a plurality of modes, an undulation suppressing effect can be obtained.

More specifically, the diaphragm has a strip shape,
The plurality of damper mechanisms are arranged on both sides of the drive mechanism along the longitudinal direction of the diaphragm.

In a strip-shaped diaphragm, rolling occurs along a vertical plane extending in the longitudinal direction. Therefore, rolling can be effectively suppressed by arranging the damper mechanism in the longitudinal direction of the diaphragm as described above.

[0016]

According to the loudspeaker of the present invention, rolling of the diaphragm can be suppressed by supporting a plurality of dampers, and the structure is simple because the driving mechanism is single.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be specifically described with reference to the drawings. As shown in FIGS. 1 and 2, the loudspeaker of this embodiment has a drive mechanism (9) and a main damper mechanism (90) having the same structure as the conventional one at the center of the diaphragm (3).
And two sub-damper mechanisms on both sides
(91) This is a combination of (91). A flat base plate (10) is joined to the opening edge of the frame (1) to form a flat frame. In this embodiment, the frame
Although (1) and the base plate (10) are formed separately, they may be formed integrally. The base plate (10) has a large opening (11) at the center, and a ring-shaped edge (2) made of an elastic material such as urethane foam or rubber is fixed to the opening. And the edge
A strip-shaped diaphragm (3) is arranged to cover the opening of (2),
The outer peripheral portion is bonded and fixed to the edge (2). Diaphragm
(3) is made of, for example, aluminum and has a honeycomb structure (not shown).

A drive mechanism (9) and a main damper mechanism (90) are connected to the center of the diaphragm (3). Drive mechanism (9)
The configuration of the main damper mechanism (90) is the same as that of the related art, and a description thereof will be omitted.

Also, two sub-damper mechanisms (91) (91) are connected to the diaphragm (3) on both sides in the longitudinal direction of the diaphragm (3) around the connection point of the drive mechanism (9). Is done. Here, the distance A from the connection point of the drive mechanism (9) to the connection point of the left sub-damper mechanism (91), and the distance A from the connection point of the drive mechanism (9) to the connection point of the right sub-damper mechanism (91) Are set to different values.

The two sub damper mechanisms (91) and (91) have the same configuration, and the frame (1) and the diaphragm (3) have
Circular openings (13) and (32) are formed at a position away from the center of the diaphragm (3) by a distance A or B in the longitudinal direction, and are formed on the inner peripheral surface of the opening (32) of the diaphragm (3). The upper end of a cylindrical member (51) having both ends opened is adhesively fixed. On the other hand, cylindrical member
The lower end of (51) penetrates the opening (51) of the frame (1) with a margin.

A cap is provided at the upper end opening of the cylindrical member (51).
(8) is fitted. Also, the outer peripheral surface of the cylindrical member (51) is
It is connected to the back surface of the diaphragm (3) via a coupling cone (61) and to the inner surface of the frame (1) via a sub damper (71) made of cloth. Here, as the sub-damper (71), a sub-damper having lower braking performance than the main damper (7) is used. Thus, a sub-damper mechanism (91) that supports both sides of the diaphragm (3) is provided.

In the above speaker, the magnetic flux generated from the main magnet (42) is guided to the upper plate (41) and the bottom plate (43) and is focused on the gap G, thereby generating a magnetic field in the gap G. I do. Therefore, the voice coil (50) is supplied with the
(50) generates an electromagnetic force according to Fleming's left-hand rule. As a result, the diaphragm (3) vibrates integrally with the voice coil (50) and the voice coil bobbin (5), and the electric signal is converted into sound. Here, the diaphragm (3) is damper-supported at the center and is damper-supported on both sides in the longitudinal direction, so that rolling is effectively suppressed. Since the sub damper mechanisms (91) and (91) disposed on both sides of the drive mechanism (9) have the same braking performance, there is no imbalance in the rolling suppression effect.

The distance A from the connection point of the drive mechanism (9) to the connection point of the left sub-damper mechanism (91) and the drive mechanism
Since the distance B from the connection point of (9) to the connection point of the sub damper mechanism (91) on the right side is set to different values, in one mode, one of the support points is located at or near the antinode. In the case where the position is supported, even if the mode is changed and the position of the belly is shifted, there is a high possibility that the other support point exists at the shifted position, and the swell in the mode is the other support point. It will be suppressed by the point.

According to the speaker of this embodiment, the diaphragm (3)
As rolling and swelling are effectively suppressed, energy loss due to rolling and swelling is reduced, energy conversion efficiency when converting electrical signals to sound is improved, and high sound pressure can be obtained. I can do it. In addition, the voice coil (50) does not come into contact with the inner peripheral surface of the upper plate (41), and no abnormal noise is generated.

The configuration of each part of the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope described in the claims.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing the entire configuration of a speaker of the present invention.

FIG. 2 is a cross-sectional view illustrating an overall configuration of the speaker.

FIG. 3 is a cross-sectional view illustrating an entire configuration of a conventional speaker.

[Explanation of symbols]

 (1) Frame (10) Base plate (3) Diaphragm (42) Main magnet (5) Voice coil bobbin (50) Voice coil (51) Cylindrical member (7) Main damper (71) Sub damper (9) Drive mechanism ( 90) Main damper mechanism (91) Sub damper mechanism

Claims (4)

[Claims] 1. A plate-shaped diaphragm, a single driving mechanism connected to the diaphragm at the center of the diaphragm, and configured to reciprocally drive the diaphragm in accordance with an input signal; And a plurality of damper mechanisms connected to the diaphragm at a position and supporting the diaphragm with a damper, wherein the diaphragm is driven by the single driving mechanism. 2. The loudspeaker according to claim 1, wherein a main damper mechanism for damper-supporting the diaphragm is connected to a central portion of the diaphragm to which the drive mechanism is connected. 3. The loudspeaker according to claim 1, wherein the plurality of damper mechanisms are connected to the diaphragm at a plurality of asymmetric positions about the connection point of the drive mechanism. 4. The speaker according to claim 1, wherein the diaphragm has a strip shape, and the plurality of damper mechanisms are arranged on both sides of the drive mechanism along the longitudinal direction of the diaphragm. .