JPS585640B2 - speaker unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inverted cone-shaped speaker unit in which cone-shaped diaphragms are provided in opposite directions.

FIG. 1 is a cross-sectional view showing an example of a conventional moving coil type cone-shaped speaker unit. In the figure, 1 is a ring-shaped magnet with a through hole in the center, and 2 is a ring-shaped magnet arranged in this through hole. This is the center pole.

A ring-shaped top plate 3 is installed on the upper surface of the magnet 1 and faces the center pole 2.

A voice coil 4 is disposed between the center pole 2 and the top plate 3, and the voice coil 4 is fixed to the central neck of the cone 5.

The cone 5 is mechanically driven in accordance with the electric signal given to the voice coil 4.

Note that 6 is a frame that holds the outer periphery of the substantially conical cone 5, and 7 is a damper that holds the voice coil 4.

However, with such speaker units, for example, in the case of a multi-speaker system in which multiple speaker units each reproduce a predetermined frequency band,
There was a problem in that the position of the sound source of each unit was different, which caused a phase shift in the reproduced sound waves.

That is, in this type of speaker unit, the outer periphery of the frame 6 is fixed to a buttful plate on the front surface of the cabinet.

In general, the depth, diameter, etc. of the cone 5 differ depending on the reproduction band.

For this reason, in a multi-speaker system, the vibration source of each speaker unit, that is, the voice coil 4, is
The distances to the cone 5 are different, and this causes a problem in that the phase of the sound waves emitted from the cone 5 is shifted, impairing the reproduction characteristics.

For this purpose, a so-called inverted cone type speaker has been considered, in which the cone is oriented in the opposite direction to the normal one and is formed into a substantially conical shape with the center of the cone protruding toward the front.

FIG. 2 shows an example of this type of inverted cone type speaker unit, in which the voice coil 4 is arranged at the center of the top plate 3 with a coil 4b wound around one end of a bobbin 4a.

The center portion of the bobbin 4a is elastically held by a holding member 8 attached to the top plate 3 via a damper 7, and the other end portion is attached to the center portion of the cone 5 projecting forward. There is.

In such an inverted cone speaker, the mounting surface of the frame 6 to the buttful plate on the front of the cabinet and the voice coil 4 can be placed on substantially the same plane, making it easy to align the sound sources of each speaker in a multi-speaker system. be able to.

Further, since the center of the cone 5 protrudes forward, the cone 5 can be easily repaired if it is damaged, and has the advantage of providing better directivity characteristics.

However, in such a configuration, the gap A between the holding member 8 on the front surface of the top plate 3 and the cone 5 is very small.
There is a possibility that the cone 5 and the holding member 8 will come into contact with each other.

Particularly in the case of a woofer for low-pitched sounds which has a large vibrational displacement, it is necessary to provide a sufficient gap between the cone 5 and the holding member 8 in order to prevent the above-mentioned contact.

For this reason, when a long bobbin is used, there is a problem that the increased weight of the vibration system deteriorates the characteristics, and the vibration system is also mechanically unstable and has low strength.

The present invention has been made in view of the above circumstances, and is an inverted cone type that can reduce the weight of the vibration system and is free from the risk of the cone coming into contact with other parts, such as magnetic circuits, even when the cone has a large amplitude. The purpose is to provide a speaker unit.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the sectional view shown in FIG.

In FIG. 3, the same parts as in FIG. 2 are given the same reference numerals and their explanations will be omitted.

In FIG. 3, reference numeral 11 denotes a holding member disposed on the front surface of the cone 5, which has a radial arm 11a, whose outer end is attached to the frame 6, and whose inner end is provided with a ring 11b.

The outer periphery of the damper 7 is attached to the ring 11b of the holding member 11, and the tip of the voice coil 4 is attached to the inner periphery of the damper 7 to elastically hold the voice coil 4. There is.

Note that FIG. 4 is a plan view of the configuration shown in FIG. 3 as viewed from the front, that is, from the upper side of FIG.

With this configuration, the mounting surface of the frame 6 to the buttful plate on the front surface of the cabinet and the position of the sound source, that is, the voice coil 4, can be placed on substantially the same plane,
Thereby, in the case of a multi-speaker system, the positions of the sound sources of each speaker can be easily aligned.

Since this is an inverted cone type speaker unit and the damper 7 is attached to the tip of the voice coil 4, the cone 5 can be attached to the magnetic circuit, that is, the front surface of the top plate 3 without using the holding member 8 shown in FIG. They come to face each other directly, creating a relatively large gap in this area.

Therefore, even if the voice coil 4 has a large vibration displacement, such as a bass woofer, the cone 5 will not come into contact with other parts, such as the magnetic circuit, and the length of the voice coil 4 will be reduced. It can also be made shorter.

It should be noted that the better the damper 4 has good air permeability, the better the sound quality will be.

As detailed above, the present invention is an inverted cone type speaker unit in which the damper that elastically holds the voice coil is arranged only on the front side of the inverted cone, so that there is sufficient space between the cone and the magnetic circuit. It is possible to obtain a gap, shorten the voice coil dimensions, and thereby reduce the weight of the vibration system and obtain good reproduction characteristics. It is possible to provide a speaker unit that can be aligned and has good directional characteristics.

[Brief explanation of the drawing]

1 and 2 are reduced sectional views showing different examples of speaker units as prior art, FIG. 3 is a vertical sectional view showing an embodiment of the present invention, and FIG. 4 is a plan view of the same embodiment. It is. 1...Magnet, 2...Center pole, 3...Top plate, 4...
Voice coil, 5... Cone, 6...
Frame, 7... Damper, 11...
Holding member.

Claims (1)

[Claims] 1. The voice coil is held in an inverted cone-shaped speaker unit that drives a cone formed into a substantially conical shape with the center portion protruding to the front by a voice coil placed in a magnetic field and driven in response to a signal applied from the outside. A speaker unit characterized in that a damper is arranged only on the front side of the cone.