JPS63254894A - Planar speaker - Google Patents

Abstract

PURPOSE:To prevent a sound wave from being diffused to the circumference of a diaphragm by providing many ribs for maintaining air including the sound wave in the front face of the diaphragm for a plane speaker and feeding forward and opening the rear face side of an enclosure. CONSTITUTION:A middle pitched sound area and a middle and low pitched sound area components are inputted to a voice coil 15 and a high pitched sound area component is inputted to a speaker 19 for a high pitched sound area. Then, the diaphragm 12 and the diaphragm of the speaker 19 are oscillated through the coil 15 and sounded. On the front surface and the side edges of the diaphragm 12, the ribs 14 are disposed and the upper and lower edges of the diaphragm 12 are curved to the front face side, so that, the air including the sound wave of the front face side of the diaphragm 12 is retained by the ribs 14 and pushed forward. The ribs play a role for reinforcing the diaphragm 12, however, it is too large to attain the role for rainforcing since it retains the air in the front face of the diaphragm and pushes forward. Accordingly, the sound wave is prevented from diffusing vertically and horizontally of the diaphragm or to the rear side.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a flat speaker in which a rib is provided on the front surface of a diaphragm.

"Prior Art" In conventional cone-shaped speakers installed in sealed enclosures or bass reflex enclosures, the speaker is attached to a baffle plate on the front of the enclosure, so the speaker's diaphragm and diaphragm drive unit The vibrations are transmitted to the enclosure through the speaker frame, etc., causing the enclosure to resonate, and the vibration of the speaker's diaphragm compresses the air at the rear of the speaker, and the air pressure presses the enclosure wall, causing it to vibrate. The vibrations of the speaker interfere with the vibrations of the diaphragm of the speaker, that is, the acoustic characteristics of the enclosure affect the sound production, and there is a drawback that the original sound cannot be reproduced with high fidelity. Therefore, a planar speaker has been proposed in which the edge of the diaphragm of the speaker is separated from the enclosure to remove the negative effects such as the resonance of the enclosure on the sound produced by the speaker. In this flat speaker, the strength is insufficient because the front area of the diaphragm is large, so in order to reinforce this, some speakers have a honeycomb rib structure between the two diaphragms.

[Problem to be solved by the invention J However, in such a conventional flat speaker,
Since the diaphragm is a flat plate with a large surface area, sound waves are easily dissipated, and especially near the outer edge of the diaphragm, the sound waves circulate to the sides and back of the diaphragm, which affects the acoustic characteristics and reduces the quality of reproduced sound. It is the cause of this.

SUMMARY OF THE INVENTION An object of the present invention is to provide a flat speaker that solves the above-mentioned problems of conventional speakers.

"Means for Solving the Problems" The present invention has the following configuration in order to achieve the above object. That is, in a planar speaker in which a planar speaker diaphragm is provided inside an enclosure in a non-contact manner with the enclosure, air containing sound waves is held in front of the planar speaker diaphragm so as to be placed in front of the diaphragm. A large number of ribs are provided, and the rear side of the enclosure is open.

``Effect J: The diaphragm is equipped with a large number of ribs located on the front of the diaphragm, so these ribs hold the air containing the sound waves on the front of the diaphragm and send it forward, causing the sound waves to spread around the 4 circumferences of the diaphragm. Since the diaphragm is provided inside the enclosure without contacting the hollow frame and the rear side of the enclosure is open, it prevents resonance between the diaphragm and the enclosure gloss. This prevents interference between the back pressure of the enclosure and the diaphragm, thereby improving the quality of reproduced sound.

"Embodiment" An embodiment of the present invention will be described below with reference to FIGS. 1 to 7. Reference numeral 1 in Fig. 1 is an inverted T-shaped support stand, and this support stand l has a rectangular horizontal plate 1a provided horizontally, a vertical plate 1b is provided in the center, and two inverted T-shaped supports are provided on the bottom surface of the horizontal plate 1a. A conical projection 1c is provided. Vertical plate 1b
An angle iM 1 d shown in FIG. 2 is formed at a predetermined location. Two support stands 1 are arranged in parallel and spaced apart from each other, and each f'Q W of these two support stands 1 is
A hollow frame 2 (corresponding to an enclosure) is fitted into and supported by i ld.

This hollow frame 2 is formed by forming a cylinder 3 having a square cross section into a rectangular frame shape. Holes 4 are formed at both longitudinal ends of the upper and lower parts of the hollow frame 2, and these holes 4 are M5, 5
It is said that it can be opened and closed.

6 is a guide plate that guides the lid 5. The cylinder 3 is densely filled with baked sand 7 which is dried by baking the sand. Moreover, U-shaped members 8, 8 are provided at the upper part of the hollow frame 2, spaced apart by a predetermined distance, and bolts 8a are attached to these U-shaped members 8, 8, respectively.

A nut 8b is provided. A flange 9 made of sponge is provided at the inner tightening portion on the front side of the hollow frame 2. It goes without saying that the lid 5 is sufficiently fixed so as not to vibrate after the baked sand 7 is filled into the hollow frame 2.

Further, at the rear of the hollow frame 2, a mounting frame 10 made of aggregate assembled in a lattice shape is arranged at a predetermined distance from the hollow frame 2. It is attached parallel to the hollow frame 2 via stepped rods 11 fixedly provided at each corner.

In addition, it is slightly smaller than the mounting frame IO (in this example, approximately 1
00mm) Separate the diaphragm 1 in parallel to the mounting frame 10 in front.
2 is provided. This diaphragm 12 has the fiber direction as the first
It is made of balsa wood arranged in the directions of arrows C and D shown in the figure, and its upper and lower edges are curved toward the front side (left side in FIG. 2). A circular hole 13 is formed in the center of the diaphragm 12, and a large number of ribs 14 are formed on the front surface of the diaphragm 12.
are fixed perpendicularly to the front surface of the diaphragm 12 so as to intersect with each other. The rib 14 has a tapered cross section in which the plate thickness on the side of the diaphragm 12 is thicker than the plate thickness on the tip side.
The average plate thickness of the ribs 14 is thin at about 1.5 mm, and the height from the front of the diaphragm 12 is high at about 20 mm. In particular, the height of the central vertical rib 14 is set even higher to about 40 mm. There is.

At four locations on the rear surface of the diaphragm 12, there are voice coils (moving coils) +5 that are components of speakers for sound ranges other than high range (for example, speakers for medium range, speakers for medium and low range). It is fixed perpendicular to the rear surface. A plurality of ribs 15a made of a piece of wood are bonded to the base of each of these voice coils 15, and the fiber direction is perpendicular to the directions of arrows A and B shown in FIG. is bonded to the diaphragm 12. The diaphragm 12 is made of resin so that it is allowed to move in the front-rear direction (in the arrow AB force direction shown in FIG. 2) inside the hollow frame 2 without contacting the hollow frame 2, and is prevented from moving in other directions. (llffi moving plate movement regulating means) 16. That is, the threads 16 each have one end attached near the four corners of the hollow frame 2.
The diaphragm 12 is attached to the other end near the edge of the hole 4 in the center of the diaphragm 12 and is suspended.

On the other hand, at a portion of the mounting frame IO facing each voice coil 15, there is a pipe having a permanent magnet, which is a component of a speaker for a sound range other than the high range (for example, a speaker for a medium range, a speaker for a mid-low range). A center ball 17 is partially fitted coaxially with the voice coil 15 and is attached with bolts and nuts so that its position can be freely adjusted. In other words, the voice coil! 5. The center ball 17 having a permanent magnet has a structure similar to that of a cone-type speaker for the above-mentioned range except for the treble range, with the cone (diaphragm) and frame removed. Therefore, the diaphragm 12
．． A voice coil I5 and a center ball 17 having a permanent magnet constitute a speaker for a range other than the treble range.

Further, a cone I8 is attached to the central circular hole 13 of the diaphragm 12, passing through the diaphragm 12, as shown in FIG. At a position facing the circular hole 13 on the rear side of the diaphragm 12, there is a high-frequency speaker 19 facing the circular hole 13.
The treble range speaker 19 is attached to the mounting frame 10 with bolts and nuts so that its position can be adjusted freely.

In addition, when a midrange speaker is used as the speaker for the sound range other than the treble range, a separate bass range speaker that is separated from the flat speaker for the midrange and treble range is used as the bass range speaker. shall be.

Next, the operation of the speaker configured as described above will be explained. First, for example, mid-range and mid-low range components of the output signal of the amplifier are input to the voice coil 15, and high-range components of the output signal of the amplifier are input to the high-range speaker 19.

Then, the center ball 17. which has a permanent magnet. Vibration plate via voice coil I5! 2 vibrates, and the diaphragm of the high-range speaker 19 vibrates to generate sound.

At this time, a large number of ribs 14 are provided on the front surface of the diaphragm 12, ribs 14 are also provided on the left and right edges of the front surface of the diaphragm 12, and the upper and lower edges of the diaphragm 12 are curved toward the front side of the diaphragm 12. Therefore, air having sound waves on the front side of the diaphragm 12 is retained by these ribs 14 and pushed out to the front of the diaphragm 12. The ribs 14 also have the role of reinforcing the diaphragm, but as mentioned above, they are too large to serve only the reinforcing role, and as mentioned above, they hold the air in front of the diaphragm 12. This is to push it forward. Therefore, the sound waves are prevented from scattering to the top, bottom, right and left of the diaphragm, or from circulating to the rear side of the diaphragm 12.

Also, at this time, the diaphragm 12 is suspended only by the threads 16 and is a free edge, so the response to input signals is excellent, and the vibrations of the diaphragm 12 are not transmitted to the hollow frame 2. Moreover, since the hollow frame 2 is filled with baked sand 7, even if the vibration of the diaphragm 12 or other objects is transmitted, it will be converted into thermal energy. Vibration and resonance with the hollow frame 2 are reliably prevented. Therefore, unlike in the past, the acoustic characteristics of the enclosure no longer have a large effect on sound production, and since the four voice coils 15 are provided at predetermined locations spaced apart from each other on the diaphragm 12, the vibration is divided. With the speaker of this embodiment, the pure sound produced by the sounding body (diaphragm) can be heard directly, so that very clear high-quality sound can always be obtained.

In addition, since the high-frequency speaker 19 is placed in the cone 18 of the circular hole 13 provided in the center of the diaphragm 12, the sound localization is good, the sound field is natural, and the high-pitched sound is good. Due to the presence of the cone 18 and the diaphragm I2, the sound waves from the sound range speaker 19 can be prevented from going to the rear of the high range speaker 19, which also contributes to obtaining high sound quality.

In addition, the mounting frame IO at the rear of the diaphragm 12 is made of aggregate assembled in a lattice shape, and the rear of the diaphragm 12 is open, so there is no interference between the back pressure of the hollow frame 2 and the diaphragm 12. can be reliably prevented.

In addition, when using several IV speakers of this embodiment, a connecting square rod 20 is inserted into the U-shaped member 8 of the plurality of speakers and fixed with bolts 8a and nuts 8b. It is best to connect speakers.

Further, when it is desired to use the speaker of this embodiment in a horizontally elongated state, the support base l fits into the hollow frame 2, thereby making this possible.

In the above embodiment, the round high-frequency speaker 9 was provided facing the circular hole 13 and the cone I8, but the present invention is not limited to this. A ribbon-shaped speaker may be attached to the edge.

In addition, in the first embodiment, the treble range speaker 9 was provided facing the circular hole I3, but the present invention is not limited to this, and the diaphragm plate is not provided with the circular hole 13 and the treble range speaker. 12, the voice coil 15, the center ball 17, etc. may be of a full range speaker.

In addition, in the self-recorded embodiment, the diaphragm 1 is placed inside the hollow frame 2.
2 is provided, but the present invention is not limited to this, and a diaphragm 12 having ribs 14 is provided inside a normal enclosure,
The rear side of the enclosure may be open.

"Effects of the Invention" According to the present invention, in a flat speaker in which a diaphragm for a flat speaker is provided inside an enclosure in a non-contact manner with a surface pressure enclosure, the front surface of the diaphragm for a flat speaker contains sound waves. Since the enclosure has a large number of ribs that hold air and send it out to the front of the diaphragm, and the rear side of the enclosure is open, the ribs on the front of the diaphragm have the role of reinforcing the diaphragm and also prevent vibrations. In other words, by providing a large number of ribs on the front side of the diaphragm, the air containing the sound waves on the front side of the diaphragm is retained, and the air on the front side of the diaphragm is immediately transferred to the front side of the diaphragm. Therefore, the sound waves can be reliably sent out to the front of the diaphragm by preventing them from scattering to the top, bottom, left and right of the diaphragm, or from going around to the rear side of the diaphragm. , the response to input signals can be extremely improved, and the vibration of the diaphragm can be prevented from being transmitted to the enclosure, thereby reliably preventing resonance between the vibration of the diaphragm and other objects and the enclosure. Furthermore, it is possible to prevent interference between the back pressure of the enclosure and the diaphragm, and as a result, the acoustic characteristics of the enclosure do not have a large effect on sound production as in the past, and the sounding body (diaphragm)
You can directly hear the pure pronunciation of the words, and as a result, you can always obtain extremely clear high quality sound.

[Brief explanation of the drawing]

1 to 7 show an embodiment of the present invention,
Fig. 1 is a front view, Fig. 2 is a partially cutaway side sectional view, Fig. 3 is a perspective view of a diaphragm with ribs, Fig. 4 is a schematic perspective view showing the rear side of the diaphragm, and Fig. 5 is a sectional view of the main part showing the relationship between the cone provided on the diaphragm and the high-frequency speaker, FIG. 6 is a sectional view taken along the line Vl-Vl in FIG. 1, and FIG. It is a cross-sectional view along the -■ line. 2...Hollow frame, 7...Baked sand (vibration isolation member)
, IO......Mounting frame, 12...Diaphragm, 13...Circular hole (through hole), I4...
Rib, 15...Voice coil, 16...
- Thread (diaphragm movement regulating member) 17...Center ball, 19...Treble range speaker.

Claims (1)

[Claims] In a flat speaker in which a flat speaker diaphragm is provided inside an enclosure in a non-contact manner with the enclosure, a large number of air containing sound waves are held in front of the flat speaker diaphragm and are sent out in front of the diaphragm. A planar speaker characterized by having a rib and an open rear side of the enclosure.