JPH0667033B2 - Speaker - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small-sized speaker capable of reproducing bass tones with high efficiency.

2. Description of the Related Art As a conventional speaker, a dynamic type in which a paper cone is used as a diaphragm and the diaphragm is directly moved in parallel by a force generated by a magnetic field and an electric current is used. (For example, Takeo Yamamoto "Speaker System (above)" (Sho 52
Year) Radio Technology Co., P143 to P147) Hereinafter, a conventional speaker as described above will be described with reference to the drawings.

FIG. 3 shows a cross section of a conventional speaker. Third
In the figure, 1 is a diaphragm, 2 is an edge whose inner peripheral edge is adhered to the outer peripheral edge of the diaphragm 1 and whose outer peripheral edge is fixed to a frame 6, 3 is a center cap fixed to the inner peripheral portion of the diaphragm 1, and 4 is the lower end. A voice coil 5 whose upper end is fixed to the inner peripheral portion of the diaphragm 1, and 5 is a damper whose inner peripheral end is fixed to the voice coil 4 and whose outer peripheral end is fixed to the frame 6,
Is a plate fixed to the lower end of the frame 6, 8 is a magnet fixed to the lower end of the plate, and 9 is a pole piece fixed to the lower end of the magnet. The operation of the conventional speaker configured as above will be described below.

First, a magnetic gap is formed between the plate 7 and the pole piece 9 by the magnetic flux of the magnet 8, and when a voice current flows in the voice coil 4 existing in the gap, a force is generated by Fleming's left-hand rule and becomes a driving force. This driving force vibrates the diaphragm 1 and the center cap 3 to generate a sound. At this time, the damper 5, the edge 2 is the diaphragm 1,
The voice coil 4 is held in a fixed position, and the edge 2 prevents the sound behind the diaphragm 1 from leaking to the front surface. Further, the frame 6 is positioned by fixing the edge 2, the damper 5, and the plate 7.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described configuration, it is difficult to increase the amplitude of the diaphragm by using a small speaker having a small diaphragm area to hold a sufficient sound pressure and reproduce bass. It was impossible. Therefore, generally speaking, bass speakers use a large-diameter diaphragm, which makes the system large.
There was a problem that it could not be miniaturized.

In view of the above problems, the present invention provides a speaker capable of sufficiently reproducing low sound with a small diaphragm.

Means for Solving the Problems In order to achieve this object, a speaker of the present invention has both ends joined to a diaphragm, and the diaphragm is movable in a rotation direction around a diaphragm support shaft. A member holding a diaphragm support shaft is provided, the diaphragm support shaft is fixed to a frame, and the upper end portion is fixed to the diaphragm, and the lower end portion is fixed to a voice coil via driving members, respectively. The driving force from the voice coil is transmitted to the diaphragm.

With the above-described structure, the present invention makes it possible to increase the amplitude of the entire diaphragm as compared with the amplitude of the drive unit according to the principle of leverage by driving the diaphragm support shaft as a fulcrum and driving a portion slightly away from the fulcrum. The bass reproduction is better than that of a conventional speaker having a diaphragm of the same area.

Embodiment One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structure of a speaker in one embodiment of the present invention, and FIG. 2 is a top view thereof. Figure 1,
In FIG. 2, 10 is a diaphragm, 11 is a diaphragm support shaft, and 1
Reference numeral 2 is a bending member that joins the diaphragm 10 at its tip flat surface and is fixed to the diaphragm support shaft 11 at its center. 13 is a frame for fixing the diaphragm support shaft 11. 14 is an upper end of the diaphragm 1.
The drive plate is fixed to 0 and the lower end is fixed to a voice coil (not shown).

The operation of the speaker configured as above will be described below. First, by transmitting the driving force from the voice coil to the diaphragm 10 via the driving plate 14, the diaphragm 10 is vertically vibrated about the diaphragm support shaft 11 to generate a sound. At this time, the diaphragm 10 is fixed to the diaphragm support shaft 11 by the bending member 12 and the diaphragm support shaft 1
It can move in the direction of rotation around 1. Further, the frame 13 fixes the diaphragm support shaft 11 and holds the diaphragm 10 at a fixed position.

As described above, according to the present embodiment, when the vibration plate 10 is vibrated up and down by the drive plate 14 with the vibration plate support shaft 11 serving as a fulcrum, the amplitude of the vibration plate 10 becomes larger than that of the drive plate 14 according to the principle of leverage. Since the diaphragm 10 can be moved,
When the area of the diaphragm is the same, it is possible to satisfactorily reproduce the low sound range that requires a large amplitude, as compared with the conventional speaker in which the amplitude of the voice coil for driving the diaphragm and the amplitude of the diaphragm are equal. Further, the diaphragm 1 of the conventional speaker has an edge 2
However, according to the present embodiment, the diaphragm 10 is fixed by the diaphragm support shaft 14 so that the gap between the diaphragm 10 and the frame 13 can be kept narrow, and the acoustic resistance due to the air in this gap is reduced to the edge. As an alternative, there is an advantage that an edge that causes distortion or disturbance of sound pressure frequency characteristics is not required. Furthermore, since the amplitude of the drive plate 14 can be made smaller than the amplitude of the diaphragm 10 when the low tone is reproduced, it is possible to reduce the occurrence of distortion due to the non-linearity of the drive system.

In the present embodiment, the diaphragm support shaft 11 and the bending member 12 are used as the method of supporting the bent portion of the diaphragm 10. However, the diaphragm support shaft 11 is covered with a pipe, and the diaphragm support shaft 11 is used as a center. Any structure can be used as long as it can rotate, and the same effect can be obtained. Further, the shape of the diaphragm is not limited to a quadrangle, and may be a circle, an oval, an ellipse or the like depending on the purpose of use. As the diaphragm, any material may be used as long as it is light and has high rigidity, and examples thereof include a polymer foam, an aluminum honeycomb sandwich structure, and a sandwich structure having a plastic molded body as a core material.

Advantageous Effects of Invention The present invention holds the diaphragm support shaft so that the diaphragm can move in the rotational direction about the diaphragm support shaft, and applies a driving force from the voice coil to the diaphragm through a driving member. By driving the diaphragm with the diaphragm support shaft as a fulcrum, the amplitude of the diaphragm can be increased with a small drive amplitude, so that good bass reproduction is possible even with a small size, and the edge is Since the speaker does not exist and the distortion of the driving unit can be reduced, a speaker having excellent acoustic characteristics can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of an embodiment of the present invention,
FIG. 2 is a top view thereof, and FIG. 3 is a sectional view showing a structure of a conventional speaker. 10 ... Vibration plate, 11 ... Vibration plate support shaft, 12 ... Bending material, 13 ... Frame, 14 ... Driving plate.

Claims (1)

[Claims] 1. A member, which is joined to a diaphragm at both ends thereof, holds the diaphragm support shaft so that the diaphragm is movable in a rotational direction around the diaphragm support shaft, and the vibration is provided. By transmitting a driving force from the voice coil to the diaphragm through a driving member having a plate support shaft fixed to the frame, an upper end portion fixed to the diaphragm, and a lower end portion fixed to the voice coil. A speaker configured to drive the diaphragm with the diaphragm support shaft as a fulcrum.