JP2949957B2 - Speaker damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic speaker.

[0002]

2. Description of the Related Art In recent years, an electro-dynamic loudspeaker as one of electro-acoustic transducers is often used for reproducing music and voice.

A conventional electrodynamic loudspeaker will be described below with reference to the drawings. As shown in FIG. 5, the electrodynamic speaker includes a magnet 1, an upper yoke 2 provided on an upper surface of the magnet 1, a lower yoke 3 provided on a lower surface of the magnet 1, and a center pole 4 continuous with the lower yoke 3. A magnetic gap 5 formed between the inner circumferential surface of the upper yoke 2 and the outer circumferential surface of the center pole 4, a frame 6 provided on the upper surface of the upper yoke 2, a voice coil 7 accommodated in the magnetic gap 5, and an inner circumference. To the voice coil 7, a damper 8 having a waveform whose outer periphery is fixed to the frame 6, an inner periphery to the voice coil 7, a diaphragm 9 having the outer periphery fixed to an edge described later, an inner periphery to the diaphragm 9, and an outer periphery to the frame 6. , And the like.

The operation of the electro-dynamic loudspeaker configured as described above will be described below. When a current flows through the coil wound around the voice coil 7, the current is orthogonal to the magnetic field in the magnetic gap 5, and a force is generated in a direction perpendicular to the magnetic field and the current according to Fleming's law.
At this time, the damper 8 and the edge 10 are
Is supported concentrically with the center pole 4, and when the diaphragm 9 vibrates, a force is applied so that the midpoint in the thickness direction of the upper yoke 2 and the midpoint of the coil width of the voice coil 7 coincide. Acts as a directional spring. When an alternating current is applied to the voice coil 7, the voice coil 7 and the diaphragm 9
In addition, since the air is vibrated while being supported by the edge 10, the air vibrates and a compression wave is generated, and the sound is heard.

[0005]

However, in the above-mentioned conventional structure, the first problem is that the conventional wave-shaped damper 8 has a structure closed in the circumferential direction. As shown in FIG. 7, when an arbitrary point P is considered, if the damper vibrates by △ X, the diameter of the point P becomes △.
r, and a force is generated in the circumferential direction. For this reason, large-amplitude vibration becomes difficult, and the "force-displacement" shown in FIG.
As shown by the curve A in the characteristic diagram, the displacement is saturated at the time of large amplitude, and the stiffness becomes non-linear.

As a second problem, as shown in the "force-displacement" characteristic diagram at the time of minute input of the characteristic A shown in FIG. 4, when the displacement is small, the restoring force of the damper is very small and the stiffness is not high. It becomes a straight line. There has been a problem that harmonic distortion occurs in the sound pressure frequency characteristics due to these phenomena.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to improve the non-linearity of a damper causing distortion and to provide a speaker damper having good linearity.

[0008]

In order to achieve the above object, a speaker damper according to the present invention is characterized in that the boundary between the fixed part and the movable part is a straight line, and that the middle part of the movable part is straight from both ends of a semicircle. A plurality of pieces each having a roll-shaped cross-sectional shape obtained by extending are arranged radially around the voice coil, and the frame fixing portion of each piece is fixed to the frame while tension is applied in the outer peripheral direction.

[0009]

According to the present invention, a loudspeaker damper having good linearity from a minute amplitude to a large amplitude can be obtained.

[0010]

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

As shown in FIGS. 1 and 2, the damper includes a frame fixing portion 11, a rolled movable portion 12, a movable portion outer peripheral boundary line 13 which is a boundary between the frame fixing portion 11 and the movable portion 12, and a voice coil. Fixed part 14, movable part inner peripheral boundary line 1 which is a boundary line between movable part 12 and voice coil fixing part 14
5, a voice coil 16 fixed to the inner periphery of the voice coil fixing portion 14.

The operation of the speaker damper constructed as described above will be described below. The sounding operation of the speaker unit is the same as in the conventional example. Movable part 12, movable part outer peripheral boundary line 13, movable part inner peripheral boundary line 1
5 is constituted by a straight line parallel to a tangent on the circumference of the voice coil 16, no force is generated in the circumferential direction as described in the operation of the conventional damper, and the movable unit 1
Since the roll-shaped pieces 2 are vertically symmetrical, the "force-displacement" characteristic diagram at the time of large amplitude shown in FIG.
Stiffness with excellent linearity is obtained up to a large amplitude like a curve. Further, since the frame fixing portion of the damper is fixed to the frame with tension applied in the outer peripheral direction, the damper can be vibrated without using a portion having a very small restoring force at the time of minute amplitude, as shown in FIG. A stiffness with good linearity can be obtained as shown in B of the "force-displacement" characteristic diagram at the time of minute amplitude.

[0013] Here, if the frame fixed end is fixed by applying a force in the inner circumferential direction, it passes through a vibration position where tension is not applied to the damper in the middle of vibration, and a restoring force is applied before and after this position. Becomes weak, resulting in non-linear stiffness. In addition, a non-linear stiffness is similarly obtained in the method of applying tension by alternately raising and lowering the frame fixing portions of adjacent pieces in the height direction. Therefore, the tension in the outer circumferential direction that can apply tension to the movable portion 12 is effective regardless of the displacement amount. The speaker damper of the present embodiment is often used for a speaker unit that requires a large amplitude, and has a cross-sectional shape extending straight from both ends of a semicircle in the middle of the movable part 12 to enable the large amplitude. The shape was a roll. further,
As shown in the plan view of FIG. 1A, in order to provide durability at the time of large amplitude, a trapezoidal piece is formed so that the area of the movable portion 12 which repeats bending can be increased.

In this embodiment, the number of individual pieces is ten, but any number may be used.

[0015]

As is apparent from the above embodiments, the present invention is characterized in that the boundary between the fixed part and the movable part is a straight line, and that the sectional shape extending straight from both ends of the semicircle in the middle of the movable part. A plurality of roll-shaped pieces are arranged radially around the voice coil, and the frame fixing part of each piece is fixed to the frame with tension applied in the outer peripheral direction, so that small amplitude to large amplitude Thus, a stiffness with good linearity is obtained, and an excellent speaker damper with less distortion can be realized.

[Brief description of the drawings]

1A is a plan view of a speaker damper according to an embodiment of the present invention, and FIG.

FIG. 2 is a perspective view of the speaker damper of the embodiment.

FIG. 3 is a "force-displacement" characteristic diagram of the speaker damper at a large amplitude.

FIG. 4 is a "force-displacement" characteristic diagram of the speaker damper at a small amplitude.

FIG. 5 is a sectional view of a speaker unit using a conventional speaker damper.

FIG. 6 is a sectional view of the speaker damper when vibrating.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Frame fixed part 12 Movable part (roll shape) 13 Movable part outer peripheral boundary line 14 Voice coil fixing part 15 Movable part inner peripheral boundary line 16 Voice coil

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-152798 (JP, A) JP-A-57-135597 (JP, A) JP-A-51-95834 (JP, A) 39398 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) H04R 9/02

Claims (5)

(57) [Claims] 1. A mobile phone comprising a support fixed to a frame so as to support a voice coil which moves up and down, wherein a boundary between the fixed part and the movable part is straight, and a semicircle is formed in the middle of the movable part. A speaker damper in which a plurality of pieces each having a roll shape in cross section extending straight from both ends are radially arranged around the voice coil. 2. The loudspeaker damper according to claim 1, wherein the individual pieces in the form of rolls are arranged alternately upward and downward. 3. The speaker damper according to claim 1, wherein each of the roll-shaped pieces is arranged to extend along a straight line parallel to a tangent on the circumference of the voice coil. 4. The plan view of each piece is such that the voice coil side has a short side,
2. A trapezoidal shape having a long side on the frame side.
A speaker damper as described in the above. 5. A speaker damper comprising: a frame fixing portion of each individual piece fixed to a frame with tension applied in an outer peripheral direction.