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Speaker

A loudspeaker and through-hole technology, which is applied in the field of loudspeakers, can solve the problems of unstable support of axis 8 and inability to completely stop abnormal sounds, and achieve the effect of suppressing the occurrence of abnormal sounds

Inactive Publication Date: 2003-05-14
PANASONIC CORP
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, although measures such as inserting a sound-absorbing material between the shaft 8 and the vibrating plate 9 are necessary, after the countermeasures are taken, the support of the shaft 8 is unstable, and there is still a problem that the abnormal sound cannot be completely suppressed.

Method used

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Embodiment 1

[0025] An embodiment of the present invention will be described below using FIG. 1 and FIG. 2 .

[0026] As shown in FIG. 1, the loudspeaker of the present invention comprises a magnetic circuit A formed by a yoke 2a, a magnet 3a, and a top plate 4a, and a through hole 2b is provided in the center thereof. The frame 1 is fixed on the yoke 2a of the magnetic circuit A. The vibrating plate 9 and the edge 10 are fixed by the frame 1 . The bobbin 17 of the voice coil 12 is fixed on the inner periphery of the diaphragm 9, and the voice coil 12 is held in the magnetic gap 15 formed by the yoke 2a and the top plate 4a. The center cover 13 is fixed to the upper end of the bobbin 17 after the central shaft is aligned with the bobbin 17 .

[0027] The bearing 5 is fixed after the through hole 2b is aligned with the central axis. The shaft 8 is vertically supported by the bearing 5 while the upper end thereof is fixed to the center of the center cover 13 .

[0028] The recessed part ...

Embodiment 2

[0035] Next, the second embodiment of the present invention, especially the differences from the first embodiment will be described with reference to FIG. 3 and FIG. 4 .

[0036] Fig. 3 is a sectional view of the speaker of this embodiment, and Fig. 4 is a characteristic diagram showing the maximum amplitude-frequency characteristic. As shown in FIG. 3 , the speaker of this embodiment differs from Embodiment 1 in that it has a damper 11 whose outer periphery is bonded to the frame 1 and whose inner periphery is bonded to the voice coil bobbin 17 . In the case where there is no damper 11 as described in Example 1, although sufficient flexibility of the vibrating part is obtained, the edge 10 that moves up and down cannot be controlled even if it is stretched to the extent that it breaks, because of the jumping phenomenon or the vertical asymmetry of the amplitude. prone to distortion. Due to the modified structure of this embodiment, the loudspeaker is more stable and the dist...

Embodiment 3

[0040] Fig. 5 is a sectional view of a loudspeaker according to Embodiment 3 of the present invention, and Fig. 6 is a sectional view of a bearing of main components. Next, differences between the speaker of this embodiment and Embodiments 1 and 2 will be described.

[0041]As shown in FIG. 5 , the speaker of this embodiment is different from Embodiment 1 in that a bearing cover 16 is provided around the through hole 12 b on the upper surface of the top plate 4 , and the bearing cover 16 surrounds the bearing 5 . When the magnetic fluid 7 seeps out from the upper end of the bearing 5 , the magnetic fluid 7 is attracted to the magnetic gap 15 if the bearing cover 16 is not present. If the magnetic fluid 7 is attracted into the magnetic gap 15 in large quantities, abnormal noise may occur due to the magnetic fluid 7 clogging the magnetic gap 15 , and abnormal noise may occur between the bearing 5 and the shaft 8 due to insufficient magnetic fluid 7 . The purpose of this embodim...

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Abstract

A speaker having a through hole made in a magnetic circuit, a recess for holding a magnetic fluid made in the periphery of the through hole, a bearing provided in the through hole, and a shaft bonded to a center cap bonded to a voice coil while being supported movably up and down by means of the bearing. The magnetic fluid fills the gap between the bearing and the shaft. The speaker can realize a conventionally unattainable low f0 by eliminating a damper. Furthermore, the speaker can operate with a large amplitude by absorbing friction or resonance between the bearing and the shaft through the magnetic fluid and supplying the magnetic fluid smoothly between the bearing and the shaft while holding it in the recess thereby suppressing generation of abnormal sound.

Description

technical field [0001] The present invention relates to loudspeakers used in various audio-visual machines. Background technique [0002] The loudspeaker in the prior art will be described below through the sectional view of the loudspeaker in FIG. 7 . And FIG. 8 is a sectional view of another speaker in the prior art. The loudspeaker of prior art is shown in Figure 7, is made of frame 1, yoke 2, magnet 3, top plate 4, vibrating plate 9, edge 10, damper 11, voice coil 12, dustproof cover 14, and magnetic gap 15 . The effect of edge 10 is mainly to keep the center and airtightness of vibrating plate 9, and the effect of damper 11 is mainly to keep the center of vibrating plate 9 and utilize its softness to control the low-range resonant frequency (hereinafter referred to as f 0 ). [0003] The higher the softness of the damper 11, the higher the softness of the speaker as a whole, f 0 just low. Since the speaker's low-range reproduction limit frequency is basically defi...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H04R9/02H04R9/04
CPCH04R9/045H04R9/027H04R9/041H04R9/02
Inventor 山岸清
Owner PANASONIC CORP