JP2000308173A - Loudspeaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a loudspeaker capable of providing high sound quality. SOLUTION: This speaker is provided with a plate (enclosure) 29 equipped with a hole part 34 and a speaker unit 19 composed of a cone-shaped part 31 and a driving part 32 provided at the center of the cone-shaped part, the hole part 34 is formed so that the opening area of a front side 34a is larger than the opening area of a back side 34b of the plate 29, the speaker unit 19 is positioned so that an outer peripheral edge part can face the hole part 34 on the back side of the plate 29, and a plate (sound quality control means) 36 for suppressing a high-range component is provided on the front side 34a of the plate of the opening part of the hole part 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker having an enclosure and a speaker unit.

[0002]

2. Description of the Related Art Conventionally, even in a single cone loudspeaker system using one loudspeaker, a dedicated loudspeaker for bass and treble or for bass, middle and treble in order to reproduce a wide range of sound without difficulty. In a two-way or three-way multi-speaker system using a combination of the above, a large-diameter large-sized speaker unit is used in a single enclosure in order to sufficiently reproduce bass. . As such a loudspeaker, a loudspeaker unit for a low frequency range, a loudspeaker unit for a medium frequency range, and a loudspeaker unit for a high frequency range are generally mounted on a baffle plate of an enclosure, and these speaker units are housed in an enclosure.

[0003]

By the way, in the above-mentioned conventional loudspeaker, a signal in which a middle and high frequency range is electrically cut is transmitted to a low range loudspeaker by using a coil or a capacitor in advance. At this time, not only the middle and high range is cut off at the end, but also the electric signal in the low range is deteriorated, so that the original sound cannot be faithfully reproduced. further,
Since the speaker unit is attached to the front baffle plate, the vibration of the vibrating portion of the diaphragm of the speaker unit and the vibration of the driving portion are transmitted to the enclosure via the frame of the speaker unit and the like, resulting in the vibration of the enclosure. Further, the vibration at the rear of the speaker unit is compressed by the vibration of the cone of the speaker unit, and the wall pressure of the enclosure is pressed and vibrated by the air pressure, and this vibration interferes with the vibration of the cone of the speaker unit.
For this reason, the acoustic characteristics of the enclosure affect sound production,
This causes the reproduction sound quality to deteriorate.

[0004] In view of the above circumstances, it is an object of the present invention to provide a speaker capable of obtaining high sound quality.

[0005]

According to a first aspect of the present invention, there is provided a loudspeaker comprising: an enclosure provided with a hole; and a loudspeaker unit comprising a mortar-shaped cone and a drive provided in the center thereof. The opening is formed so that the opening area on the front side is larger than the opening area on the rear side of the enclosure, and the speaker unit is located on the rear side of the enclosure so that the outer peripheral edge faces the hole. A sound quality control means for suppressing high-frequency components is provided in the opening on the front side of the enclosure.

With this configuration, the speaker according to the present invention has the following operation. That is,
Since an air layer is present in the hole between the cone and the sound quality control means, it is difficult for middle and high frequency range components to be transmitted.In addition, the sound quality control means provided in the opening is generated by the vibration of the cone part. The middle and high frequency components of the vibration are cut. Therefore, since it is not necessary to use a capacitor or a coil to cut off the middle and high frequencies electrically, the electric signal for vibrating the cone portion does not change, and the original sound can be faithfully reproduced. Therefore, a full-range speaker unit can be used as the speaker unit. The cut may be made only in the high frequency range.

According to a second aspect of the present invention, in the speaker according to the first aspect, the sound quality control means is a plate.

In this loudspeaker, since a plate is provided at the opening of the hole, an air layer is formed on the rear side of the plate. The transmission of the middle and high frequency range components becomes difficult by passing through the air layer, and further, by increasing the mass of the plate member, the vibration having a large frequency can be regulated, and the transmission of the middle and high range range components can be cut. In addition, the bass component is vibrated by the compressional waves of the air layer on the front surface, so that the bass component is sent out to the front surface of the plate with a larger air volume and amplitude.

According to a third aspect of the present invention, in the speaker according to the second aspect, a lead material is attached to the plate material.

In this speaker, since the lead material is attached, the mass of the sound quality control means increases,
It is possible to cut the mid-high range more efficiently.

According to a fourth aspect of the present invention, in the speaker according to any one of the first to third aspects, an opening area of the hole on the rear surface side of the enclosure is smaller than an outer diameter of the speaker unit. It is characterized by being.

Further, the speaker according to claim 5 is the speaker according to any one of claims 1 to 4, wherein the enclosure is provided with a diaphragm for a planar speaker separately from the hole. A diaphragm driving mechanism for providing a large number of ribs for holding air containing sound waves and sending it out in front of the diaphragm and opening the rear surface of the enclosure to vibrate the diaphragm, Is provided. According to a sixth aspect of the present invention, in the speaker according to any one of the first to fifth aspects, the speaker unit is supported by a frame fixed to an enclosure.

In this speaker, a low-frequency component is emitted from the hole, and a medium-high frequency component is generated from the diaphragm. Since the planar speaker diaphragm is provided with a number of ribs located on the front surface thereof, after the vibration of the diaphragm driving mechanism is transmitted to the diaphragm, the ribs generate air having sound waves on the front surface of the diaphragm. And send it forward reliably.
Therefore, it is possible to prevent the sound waves from being scattered around the four circumferences of the diaphragm and from rotating behind the diaphragm. In addition, since the rear side of the enclosure is open, resonance between the diaphragm and the enclosure is prevented, and interference between the enclosure and the back pressure of the diaphragm is prevented. Further, in this speaker, unlike the conventional case where the speaker unit is supported by a baffle plate or the like on the front surface thereof, the speaker unit is supported by a frame. Therefore, the vibration of the speaker unit is not transmitted to the enclosure and the enclosure does not resonate.

According to a seventh aspect of the present invention, in the speaker according to any one of the first to sixth aspects, a sound absorbing means for absorbing sound generated from the rear surface of the speaker is provided on the rear surface side of the speaker. It is characterized by.

As described above, for the sound emitted from the front of the speaker unit, the middle and high frequency components can be cut by the sound quality control means, but a sound that is not cut from the rear of the speaker may be generated. Therefore, by providing the sound absorbing means as described above, the sound generated from the rear surface of the speaker is absorbed.

[0016]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 5 shows a speaker unit used in the speaker according to the present embodiment, FIG. 6 is a cross-sectional view of the speaker unit, and FIG. 2 shows a speaker to which the speaker unit is attached. As shown in FIG. 2, the speaker 1 according to the present embodiment includes a hollow frame (enclosure) 2, a diaphragm 3, and a frame 4. The hollow frame 2 is formed by forming a rectangular tube having a rectangular cross section into a rectangular frame shape, and the inside is densely filled with baked sand dried by baking sand. Behind the hollow frame 2, a frame 4 is arranged separately from the hollow frame 2. Hollow frame 2 and frame 4
An inverted conical projection 10 is provided at the lower end.
0 supports the speaker 1.

A diaphragm 3 is located inside the hollow frame 2 in parallel with the hollow frame 2, and the diaphragm 3 is fixed to the curved plate 15, as shown in FIG. Rib 1 for holding air containing sound waves and sending it out to the front surface of diaphragm 3
6. An elastic connecting member is provided on the outer periphery of the diaphragm 3, and the diaphragm 3 is attached to the hollow frame 2 in a non-contact state by interposing the connecting member. The connecting member is made of a material having a high elasticity and a good vibration damping property, such as urethane foam resin. However, the present invention is not limited to this, and it may be suspended by a resin thread so that movement in the front-rear direction is allowed without contact with the hollow frame, and movement in other directions is prevented. In this case, the diaphragm 3 is attached to each other end of the yarn having one end attached to each of the four corners of the hollow frame 2.

The curved plate 15 is substantially cylindrical (elliptical cylinder) on both sides.
In addition to being curved so as to form a part of a surface, the central portion has a substantially planar shape and a plate shape which is curved in one direction as a whole. Near the center of the curved plate 15, two holes 17 are formed vertically. At the upper and lower ends and the center of the curved plate 15, horizontal ribs 16a having a plane shape substantially equal to the cross-sectional shape orthogonal to the axis of the curved plate 15 are fixed.
Near the center axis of the curved plate 15, a vertical rib 16b is fixed to the curved plate 15 in a direction orthogonal to the horizontal rib 16a. The vertical ribs 16 are located between the horizontal ribs 16a.
Radial ribs 16c are fixed to the curved plate 15 on the left and right sides of b. The rib 16 composed of these ribs 16a to 16c
Have a tapered cross section in which the diaphragm side plate thickness is larger than the tip side plate thickness.

It is desirable that the curved plate 15 and the rib 16 are lightweight and have high rigidity. In the present embodiment, a balsa material is used. In addition, all of these members are cut and combined so that the direction of the fiber is directed to the longitudinal direction of the member. Further, in the present embodiment, the curved plate 15 is formed into the shape shown in the figure by elastically deforming the flat plate, and the ribs 16 are maintained so that this elastically deformed state (state in which internal stress is generated) is maintained. Is fixed to the curved plate 15, and by generating internal stress in this way, the vibration propagation speed can be increased.

On the rear surface of the diaphragm 3, as shown in FIG.
Three cone type speaker units (diaphragm driving mechanism) 1
8, 18, and 19 are vertically adjacent to each other. These are all full-range speaker units, the upper two 18 and 18 are speaker units for middle and high sounds, and the lower 19 is speaker unit for low sounds. The speaker units 18, 18 and 19 are fixed to a frame 4 provided behind the hollow frame 2. A speaker holding member 21 is provided between the frames 4, and a hole 22 is formed in the speaker holding member 21 with an opening directed in the front-rear direction. The rear portions of the speaker units 18 to 19 are fitted and fixed to the holes 22.

As shown in FIG. 1, the bass speaker unit 19 is located on a rear surface of a plate member 29 which constitutes a part of the enclosure. The speaker unit 19 includes a mortar-shaped cone portion 31 and a driving portion 32 provided at the center thereof.
The frame member 30 extends from the driving portion and supports the cone portion 31. The plate member 29 is provided with a hole portion 34, and the speaker unit 19 is mounted on the frame 4 with the cone portion 31 desired by the hole portion 34. Have been.

The frame 30 supports the cone portion 31 from the back. The base end of the frame 30 is fixed to the drive portion 32, and the cone portion 31 is fixed to the outer peripheral end so as to freely vibrate. On the rear side of the cone portion 31, a sound absorbing rubber 33 is provided as sound absorbing means for absorbing sound emitted from the cone portion 31 rearward.
Is provided. The sound absorbing rubber 33 is spaced apart from the cone portion 31 so as to cover the entire rear surface of the cone portion 31.
0 is adhered inside. However, the cone part 3
When the cone 1 is closed, a resistance acts when the cone portion 31 vibrates, so that a portion is opened.

The hole 34 has an opening area on the front side larger than the opening area on the rear side of the hollow frame 2. The speaker unit 19 has an outer peripheral edge on the rear side of the plate member 29. A plate member 36 is provided in the opening 34a on the front surface side of the plate member 29 of the hole portion 34 as sound quality control means for suppressing high-frequency components. A 0.3 mm-thick lead material is attached to the rear side of the plate material 36 in order to increase the mass of the plate material. In addition, the thickness of the plate material is 2 mm including the lead material, and
The air layer 37 formed in a is 3 mm. The hole 34 provided in the plate 36 has a circular shape on the rear side 34b of the hole, a rectangular shape on the front side 34a, and a rectangular shape on the rear side 3b.
4b, the outer peripheral end opening area of the cone portion 31 is larger than the rear surface side 34b of the hole portion 34,
It is formed smaller than the front side 34a.

FIG. 5 shows the appearance of the mid / treble speaker unit 18. As shown in FIG. This speaker unit 1
Reference numeral 8 denotes a general cone type speaker unit provided with a cylinder 25. Specifically, the speaker unit 18
Includes a driving unit 26 provided at a central portion, and a mortar-shaped cone portion 27 provided on the outer peripheral side of the driving unit 26 and vibrated by the driving unit 26. A cylindrical body 25 is adhered at an intermediate position between the inner peripheral edge and the outer peripheral edge of the cone portion 27. The cylindrical body 25 is formed to have a larger diameter at the outer peripheral end side than the cone part 27 side because resonance occurs when the cylindrical body 25 has a columnar shape and sound quality is deteriorated.

The speaker unit 18 is fixed to the frame 4 as described above.
Is fixed to the frame 4 with the outer peripheral edge thereof facing the diaphragm 3, and the outer peripheral end side of the cylindrical body 25 is bonded to the diaphragm 3 so as to face the hole 17 provided in the diaphragm 3. I have. That is, in the cone portion 27, the vibration generated in a portion inside the portion where the cylindrical body 25 is bonded passes through the hole portion 17 through the air and is transmitted to the front of the diaphragm 3. Have been. Further, the vibration of the cone portion 27 is transmitted to the diaphragm 3 via the cylindrical body 25.
One of the holes 17 provided in the diaphragm 3 has a cover 2
8 is provided for adjusting the sound quality of the high frequency component.

Next, the speaker 1 configured as described above
The operation of will be described. First, the speaker unit 19
Will be described. When the output signal of the amplifier is input to the speaker unit 19, the cone 31 of the speaker unit 19 vibrates, and the sound wave is pushed out to the front through the hole 34. At this time, the opening area of the hole 34 is the front side 34a.
Is formed larger, the vibration that has passed through the hole on the rear side 34b is not applied to the air layer 3 formed on the front side 34a.
7 is transmitted. At this time, the transmission of vibration in the middle and high frequency range having a large frequency is restricted by the air layer 37 and the plate member 36 having a large mass. That is, the air layer 37 and the plate material 36
However, it acts as a mechanical impedance, so that the middle and high range is cut and only the low range is transmitted to the plate member 36. The vibration in the low-frequency range vibrates the plate member 36 through the compression wave of the air layer 37, so that the air amount and amplitude become larger and are sent out to the front of the plate portion 36. Therefore, since there is no need to electrically cut the mid-high frequency using capacitors and coils,
There is no need to change the electric signal for vibrating the cone, and the original sound can be faithfully reproduced.

Further, since the rear portion of the speaker is open, resonance between the diaphragm and the enclosure does not occur as in the prior art, and interference between the enclosure and the back pressure of the diaphragm is prevented. Further, in this speaker, the speaker unit 19 is supported by the frame 4 unlike the conventional case where the speaker unit 19 is supported by a baffle plate or the like on the front surface thereof. Therefore, the vibration of the speaker unit is not transmitted to the enclosure and the enclosure does not resonate.

Next, the speaker unit 18 will be described. Similarly to the speaker unit 19, when the output signal of the amplifier is input to the speaker unit 18, the cone unit 27
Vibrates. As a result, a high-frequency sound wave is generated from the central portion of the cone portion 27, passes through the hole 17 through the air,
It is transmitted to the front of the diaphragm 3. The vibration of the cone 27 is transmitted to the cylinder 25. As described above, since the cylindrical body 25 is bonded between the inner peripheral edge and the outer peripheral edge of the cone 27, vibration energy originally transmitted to the outer peripheral edge of the cone is transmitted to the cylinder.

The vibration transmitted to the cylinder 25 is further transmitted to the diaphragm 3. As described above, a large number of ribs 16 are provided on the front surface of the diaphragm 3, and the left and right edges of the front surface of the diaphragm 3 are curved toward the front surface of the diaphragm 3. Air is retained by these ribs 16 and is pushed forward of the diaphragm 3. In other words, the sound wave
Of the diaphragm 3 or turning to the rear side of the diaphragm 3 is prevented. Further, since the diaphragm 3 is not in contact with the hollow frame 2, the response to an input signal is very good, and the vibration of the diaphragm 3 is hardly transmitted to the hollow frame 2. In addition, since the inside of the hollow frame 2 is filled with the burning sand, even if the vibration of the diaphragm 3 and other objects is transmitted, it is converted into thermal energy. 2 is reliably prevented. Therefore, unlike the conventional case, the acoustic characteristics of the enclosure do not greatly affect the sound generation, and the pure sound can be heard directly, so that a very clear high sound quality can be obtained.

Further, since the treble is directly sounded from the hole 17, the sound is well localized and a natural sound field feeling can be obtained. In addition, the presence of the cylindrical body 25 and the diaphragm 3 also prevents the sound wave from traveling to the rear of the speaker unit 18. This is one of the reasons for obtaining high sound quality. Further, the rear of the diaphragm 3 is open only by the attachment of the frame 4. Therefore, interference between the hollow frame 2 and the back pressure of the diaphragm 3 can be reliably prevented.

The present invention is not limited to the above embodiment, but may be modified as follows. The shape of the curved plate 15 is not limited to the above, and the shape of the cross section (the cross section orthogonal to the axis) forms a part of a perfect circle or an elliptical arc, or a combination of a plurality of arcs having different curvatures. Various shapes such as a shape or a polygonal shape can be adopted. Further, not only the left and right edges of the curved plate 15 may be curved, but also the upper and lower edges may be curved. The material of the diaphragm 3 is not limited to wood as described above, and a plastic material such as polycarbonate, as well as a material (pulp or the like) used for a conventional speaker may be used. Further, the curved plate 15 does not necessarily need to be in an elastically deformed state (a state in which an internal stress is generated).
It may be in a curved state as shown by plastic deformation by heat treatment or the like.

[0032]

As described above, according to the present invention,
The vibration of the speaker unit is transmitted through the air layer and the sound quality control means. At this time, the transmission of vibration in the middle and high frequency range having a large frequency is restricted. That is, since the air layer and the sound quality control means function as a so-called mechanical impedance, the mid-high range is cut. Further, since the low sound range is transmitted to the sound quality control means having a large area via the compression wave of the air layer, the low sound area is sent out to the front of the sound quality control means with a larger air volume and amplitude. Therefore, since it is not necessary to electrically cut the middle and high frequencies using a capacitor or a coil, there is no need to change the electric signal for vibrating the cone portion, and the original sound can be faithfully reproduced. The rear of the speaker unit is open. Therefore, interference between the enclosure and the back pressure of the cone portion can be reliably prevented. From the above,
In the speaker according to the present invention, high sound quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a speaker shown as one embodiment of the present invention.

FIG. 2 is a perspective view showing an appearance of the speaker.

FIG. 3 is a diaphragm used in the speaker.

FIG. 4 is a rear view of the speaker.

FIG. 5 is a perspective view of a treble speaker unit used in the speaker.

FIG. 6 is a sectional view of the speaker unit.

[Explanation of symbols]

 Reference Signs List 19 speaker unit 29 plate material (enclosure) 31 cone portion 32 drive portion 33 sound-absorbing rubber (sound absorbing means) 34 hole portion 36 plate material (sound quality control means)

Claims (7)

[Claims] 1. An enclosure provided with a hole, a speaker unit including a mortar-shaped cone and a drive unit provided at the center thereof, wherein the hole is located in front of an opening area on the rear side of the enclosure. The speaker unit is located on the rear side of the enclosure so that the outer peripheral edge faces the hole, and the opening of the hole on the front side of the enclosure has a high-frequency component. A speaker provided with sound quality control means for suppressing noise. 2. The speaker according to claim 1, wherein said sound quality control means is a plate. 3. The loudspeaker according to claim 2, wherein a lead material is attached to the plate material. 4. The speaker according to claim 1, wherein an opening area of the hole on the rear surface side of the enclosure is formed to be smaller than an outer diameter of the speaker unit. 5. The speaker according to claim 1, wherein the enclosure is provided with a diaphragm for a planar speaker separately from the hole, and a front surface of the diaphragm for a planar speaker is provided on the enclosure. A large number of ribs are provided for holding air containing sound waves and sending out the front of the diaphragm, and a rear surface side of the enclosure is opened, and a diaphragm driving mechanism for vibrating the diaphragm is provided. Speaker. 6. The speaker according to claim 1, wherein the speaker unit is supported by a frame fixed to an enclosure. 7. The speaker according to claim 1, wherein a sound absorbing means for absorbing sound generated from the rear surface of the speaker is provided on the rear surface side of the speaker.