JP3399073B2 - Speaker - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker used for various audio equipment. 2. Description of the Related Art In recent years, high-quality sources (CD, DAT,
Etc.) have been put to practical use, but many distortions still occur in speakers that convert music signals into sound outputs. The distortion generated in the speaker can be roughly classified into two types. The distortion generated by the speaker itself in electro-acoustic conversion (distortion caused by the driving system and the support system) and the shape near the speaker after the electro-acoustic conversion. And acoustically generated distortion. If the support system is formed into a shape with good linearity to reduce the former distortion, the structure will be relatively large with respect to the diaphragm, and the wave front of the sound from the diaphragm will be disturbed, and as a result, the latter distortion will increase. Therefore, no effective improvement method has been found. Hereinafter, the above-mentioned conventional speaker will be described with reference to the drawings. FIG. 2 is a half sectional view showing a configuration of a speaker using a flat diaphragm in a conventional speaker. The lower plate 1 having a center pole 7, the ring-shaped magnet 2, and the ring-shaped upper plate 3 are shown. A magnetic circuit in which the magnetic gap 8 is formed by coupling is formed. A baffle plate 4 is coupled to the magnetic circuit, and a peripheral portion of an edge 10 coupled to a peripheral portion of a diaphragm 5 having a voice coil 6 coupled to a lower center portion is fixed to an inner peripheral portion of an upper surface of the baffle plate 4. , The voice coil 6 is fitted in the magnetic gap 8. When a current flows through the voice coil 6 inserted into the magnetic gap 8 of the above-described conventional speaker having the above-described structure, the voice coil 6 is driven by the magnetic flux in the magnetic gap 8 according to Fleming's left-hand rule. The force acts in the vertical direction, and the sound wave is generated by driving the diaphragm 5 to which the voice coil 6 is coupled, so as to perform electro-acoustic conversion. [0005] However, in the above-described conventional configuration, when current flows through the voice coil 6 and the diaphragm 5 receives a driving force and moves in the vertical direction, the edge holding the diaphragm 5 is held. Since the reaction force with respect to the driving force of the voice coil 6 in the vertical direction of 10 differs, the amplitude of the diaphragm 5 differs in the vertical direction. Further, since the relationship between the displacement of the diaphragm 5 and the reaction force of the edge 10 at that time is not proportional, the amplitude of the diaphragm 5 does not become proportional to the current flowing through the voice coil 6, and the supporting system A phenomenon called nonlinearity and asymmetry occurs. Because of these,
The resulting acoustic output has the problem of becoming distorted. Further, when the diaphragm 5 undergoes split resonance in a high frequency range, only the outer peripheral portion of the diaphragm 5 is held by the edge 10, so that the diaphragm 5 is likely to resonate, resulting in a very large disturbance in sound output characteristics. Will occur. Another problem is that the sound wave generated from the diaphragm 5 is disturbed by the edge 10 and the resulting acoustic output is disturbed in high-frequency characteristics even though the diaphragm 5 is not split and resonating. Had. [0007] It is an object of the present invention to solve such problems and to provide a speaker having excellent sound output characteristics without distortion. [0008] In order to solve the above problems, a speaker according to the present invention has a cushion made of urethane foam or foam rubber arranged and joined to the lower surface of a diaphragm to which a voice coil is connected , and This cushion is joined to the upper surface of the magnetic circuit, and the diaphragm and the baffle are
The height of the cushion is approximately the same as that of the diaphragm between
It is what was joined. According to this structure, the voice coil fixed to the diaphragm to which the cushion is connected can be held in the magnetic gap. When current flows through the voice coil and the diaphragm oscillates in the vertical direction, the magnetic circuit to which the cushion is fixed and the moving diaphragm compress and expand, and produce a reaction force proportional to the amount of displacement of the diaphragm in the vertical direction. It can be applied to the diaphragm to improve the nonlinearity and asymmetry of the support system. [0010] Further, since the cushion is fixed to most of one side of the diaphragm, when the diaphragm resonates in a high frequency range, the cushion damps the resonance of the diaphragm and the acoustic output characteristics in the high frequency region are flattened. Is done. Further, the height of the cushion is substantially the same as the height of the vibration plate having no protrusion that is equal to or more than the same plane as the vibration plate and no depression that is equal to or less than the same plane as the vibration plate, so that the wavefront of the sound wave from the vibration plate is not disturbed. Accordingly, the obtained sound output characteristics are low distortion and have little disturbance over a high frequency range. An embodiment of the present invention will be described below with reference to the drawings. Components having the same configuration as the conventional example are denoted by the same reference numerals. FIG. 1 is a half sectional view showing a configuration of a speaker according to an embodiment of the present invention. A lower plate 1 having a center pole 7, a ring-shaped magnet 2, and a ring-shaped upper plate 3 are laminated. Magnetic gap 8
Is formed. A baffle plate 4 is coupled to the upper surface of the magnetic circuit, a voice coil 6 is coupled to the inner peripheral side of the baffle plate 4 at the lower center, and urethane foam or urethane foam is coupled to an inner peripheral side and an outer peripheral side of the voice coil 6. A voice coil 6 is fitted into the magnetic gap 8 together with the diaphragm 5 to which a cushion 9 made of foamed rubber is joined. At this time, the lower surface of the cushion 9 is the center pole 7
And the upper part of the upper plate 3. The cushion 9 has a shape that fills the space between the inner peripheral side of the baffle plate 4 and the outer peripheral side of the diaphragm 5.
The heights of the cushion 9 and the baffle plate 4 are the same. In the loudspeaker of the present invention thus constructed, when a current flows through the voice coil 6 and the diaphragm 5 oscillates in the vertical direction, the loudspeaker is compressed by the magnetic circuit to which the cushion 9 is fixed and the moving diaphragm 5. In addition, a reaction force proportional to the amount of displacement of the diaphragm 5 can be applied to the diaphragm 5 in the up and down directions. In addition, since the cushion 9 is fixed to almost one portion of one surface of the diaphragm 5, when the diaphragm 5 splits and resonates in a high frequency range, the cushion 9 dampens the resonance of the diaphragm 5 and the acoustic output characteristics in the high frequency range. Flattened. Furthermore, the convexity of the cushion 9 which is equal to or more than the same plane as the diaphragm 5 or the diaphragm 5
And the height of the diaphragm that is not flush with the cushion 9
Since the height is substantially the same, the wavefront of the sound wave from the diaphragm 5 is not disturbed. As described above, in the speaker according to the present invention, when a current flows through the voice coil and the diaphragm oscillates in the vertical direction, the loudspeaker is compressed and expanded by the magnetic circuit on which the cushion is fixed and the moving diaphragm. In the vertical direction, a reaction force proportional to the amount of displacement of the diaphragm can be applied to the diaphragm, the movement of the diaphragm is proportional to the current flowing through the voice coil, and the non-linearity and asymmetry of the support system have been improved. The acoustic output characteristic obtained in a low distortion manner. Further, since the cushion is fixed to almost one surface of the diaphragm, when the diaphragm resonates in a high frequency range, the cushion damps the resonance of the diaphragm and the sound output characteristics in the high frequency region are flattened. Is done. Furthermore, the height of the cushion is substantially the same as that of the diaphragm, and the wavefront of the sound wave from the diaphragm is not disturbed. Accordingly, the obtained sound output characteristics are low distortion and have little disturbance over a high frequency range.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a half sectional view showing a configuration of a speaker according to an embodiment of the present invention. FIG. 2 is a half sectional view showing a configuration of a conventional speaker. 3 upper plate 4 baffle plate 5 diaphragm 6 voice coil 7 center pole 8 magnetic gap 9 cushion

Claims (1)

(57) [Claim 1] A buffer is provided on a magnetic circuit having a magnetic gap.
And a lower surface of a diaphragm in which a voice coil that fits into the magnetic gap is coupled, and the diaphragm and the above-mentioned battery.
A cushion made of urethane foam or foam rubber is arranged and joined between the full members, and the cushion is joined to the upper surface of the magnetic circuit, and a cushion between the diaphragm and the baffle is formed.
A speaker whose height is substantially the same as that of the diaphragm .