JPH0998497A - Edgeless speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve sound quality by providing a sliding part to be in slidable contact with the inner peripheral surface of the opening while limiting the ventilation of air in a prescribed space. SOLUTION: A sealing material 20 is stuck to the end part of a ring 16 attached to the outer peripheral end part of a diaphragm 13, it is disposed so as to tightly seal the entire space (annular space) between the diaphragm 13 or the ring 16 and the opening inner peripheral surface 9a of a frame 9, and even when pressure change occurs inside a cabinet accompanying the vibration of the diaphragm 13, the annular space is tightly sealed and the ventilation of the air through the annular space is limited. Thus, since a tightly sealed state with the opening inner peripheral surface 9a of the frame 9 is maintained and the ventilation of the air at the slidable contact part is not generated even when the pressure change occurs inside the cabinet accompanying the vibration of the diaphragm 13, sound quality degradation due to the generation of unwanted whiz noise or the like is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an edgeless speaker which is suitable for a bass speaker by removing an annular edge attached between the inner peripheral surface of the opening of the speaker frame and the outer peripheral surface of the diaphragm. .

[0002]

2. Description of the Related Art As a bass speaker in recent years,
It is a small-diameter speaker, and the ring-shaped edge attached between the inner peripheral surface of the opening of the speaker frame and the outer peripheral surface of the diaphragm is removed so that sufficient sound pressure can be obtained and sound distortion is reduced. An edgeless speaker having a configuration is known.

That is, since a minute gap (annular space) having a width of about 1 mm is formed between the inner peripheral surface of the opening of the speaker frame and the outer peripheral surface of the ring around the diaphragm, the diaphragm vibrates smoothly. Alternatively, the air flow around the diaphragm is obstructed, and the speaker functions as a bass speaker.

FIG. 4 shows an example of the configuration of such an edgeless speaker. The cancel magnet 2,
The magnetic circuit 1 is composed of the pole yoke 3, the magnet 4, and the plate 5. In the magnetic gap between the pole piece 3a and the plate 5, a voice coil 8 attached to the bobbin 7 is interposed.

The upper and lower stages of the bobbin 7 are supported by an upper damper 10 and a lower damper 11, one end of which is attached to the frame 9. Further, on the upper stage of the bobbin 7, there is a diaphragm 13 having a center cap 12 attached to the center thereof.
The central hole 14 is fixed. The ring 16 attached to the outer peripheral end portion 15 of the diaphragm 13 is separated from the opening inner peripheral surface 9a by about 1 mm so as not to contact the opening inner peripheral surface 9a of the frame 9 when the diaphragm 13 vibrates. Therefore, an annular space is formed between the ring 16 and the opening inner peripheral surface 9a of the frame 9.

When driving, the upper damper 10
When the vibrating plate 13 vibrates as the bobbin 7 supported by the lower damper 11 moves up and down, the ring 16 of the outer peripheral end 15 of the vibrating plate 13 causes the inner peripheral surface 9 of the opening 9 of the frame 9 to move.
Since the vibration amplitude of the vibrating plate 13 is increased because it moves without contacting along a, bass sound reproduction with sufficient sound pressure and low sound distortion even with a small-diameter speaker is achieved. Is possible.

[0007]

By the way, in the above-mentioned edgeless speaker, in order to smoothly vibrate the diaphragm 13, the ring 16 at the outer peripheral end of the diaphragm 13 is provided on the inner periphery of the opening of the frame 9. It is necessary to move along the surface 9a without making contact, and an annular space of a predetermined size is formed between the ring 16 and the inner peripheral surface 9a of the opening of the frame 9, but the annular space can be maintained accurately. In order to achieve this, not only rigorous accuracy is required for the mounting accuracy of each component, but also a pressure change occurs inside the cabinet due to the vibration of the diaphragm 13.
Since air circulates through the annular space and unnecessary wind noise is generated, sound quality deterioration (performance deterioration)
There is a problem that invites.

Therefore, in order to solve these problems, for example, as shown in FIG. 5, a ring-shaped sealing material 17 is attached to the entire circumference of the side surface of the ring 16 and is slid against the inner peripheral surface 9a of the opening of the frame 9. Ring 1 by touching
It is considered that the above-mentioned inconvenience is solved because not only the space between 6 and the inner peripheral surface 9a of the opening of the frame 9 is kept constant, but also the flow of air through the annular space is obstructed by the sealing material 17.

However, as shown in FIG.
When 7 is attached to the same position as the outer peripheral end portion 15 of the diaphragm 13, when the diaphragm 13 vibrates integrally with the ring 16, the sealing material 17 attached to the entire circumference of the side surface of the ring 16 is attached to the frame 9. When sliding on the inner peripheral surface 9a of the opening,
When the sealing material 17 is removed from the opening end 9b of the frame 9 and is returned to the inside of the frame 9, the opening end 9b is caught and the vibration of the diaphragm 13 is hindered.

Therefore, in consideration of the stroke of the diaphragm 13 at the time of maximum vibration, as shown in FIG.
It is considered that by removing the outer peripheral end portion 15 of 3 from the opening end portion 9b of the frame 9, it is possible to eliminate the detachment of the sealing material 17 from the opening end portion 9b of the frame 9.

However, in such a structure, the diaphragm 1
A space is created on the front side of the frame 3 by the opening inner peripheral surface 9a of the frame 9, and when the sound wave generated by the vibration of the diaphragm 13 exits the opening end 9b of the frame 9, it spreads due to the diffraction phenomenon. This causes a problem that the sound pressure is lowered and the sound quality is lowered.

Further, as described above, when the ring-shaped sealing material 17 attached to the entire circumference of the side surface of the ring 16 is brought into sliding contact with the opening inner peripheral surface 9a of the frame 9, the sealing material 17 is When sliding on the opening inner peripheral surface 9a of the frame 9, there is a possibility that sliding noise may be generated due to friction with the opening inner peripheral surface 9a of the frame 9. In order to suppress the generation of such a sliding sound, the sliding surface, which is the inner peripheral surface 9a of the opening of the frame 9, is mirror-finished to improve smoothness and suppress the generation of the sliding sound. However, conversely, by performing mirror surface treatment, the sliding contact portion between the sealing material 17 and the sliding surface which is the inner peripheral surface 9a of the opening of the frame 9 becomes a vacuum state, and an adsorption phenomenon occurs, and the sealing material is generated. Since there is a possibility that the sliding operation of 17 will not be performed smoothly, there is a problem that the sound quality is deteriorated in the same manner as described above.

The present invention has been made in consideration of such circumstances, and an object thereof is to provide an edgeless speaker capable of improving sound quality.

[0014]

According to the first aspect of the present invention,
An edgeless speaker in which an outer peripheral end of a diaphragm is movable along an inner peripheral surface of an opening of a speaker frame while maintaining a predetermined space, the outer peripheral end of the diaphragm and an inner peripheral opening of the speaker frame. The vibrating member including the vibrating plate is provided with a sliding portion that slidably contacts the inner peripheral surface of the opening while restricting the flow of air in a predetermined space between the vibrating plate and the surface.

According to a second aspect of the present invention, the outer peripheral end of the diaphragm and the opening end of the speaker frame are arranged in substantially the same plane, and the diaphragm and the inner peripheral surface of the opening of the speaker frame are disposed between the diaphragm and the speaker frame. An edgeless speaker in which an outer peripheral end portion of the diaphragm is movable along the inner peripheral surface of the opening while maintaining a predetermined space, wherein the outer peripheral end portion of the diaphragm has an inner peripheral surface of the opening of the speaker frame. The ring is attached in a state of being housed on the surface side and maintaining the predetermined space, and at a position apart from the opening end side of the speaker frame in the ring, the ring inner peripheral surface of the opening is formed. It is characterized in that a sliding portion for restricting the flow of air in a predetermined space between the sliding portions is provided.

According to a third aspect of the present invention, the sliding portion is formed of a porous member.

The invention according to claim 4 is characterized in that the sliding portion is formed of a fibrous porous member.

According to a fifth aspect of the invention, the sliding portion contains a lubricant.

According to a sixth aspect of the present invention, the sliding portion is formed of a semi-closed cell material and contains a lubricant.

[0020]

In the edgeless speaker of the present invention, the vibrating member including the vibrating plate is provided in the opening while restricting the flow of air in a predetermined space between the vibrating plate and the inner peripheral surface of the opening of the speaker frame at the outer peripheral end. Since the sliding part that slidably contacts the peripheral surface is provided, even if a pressure change occurs inside the cabinet due to the vibration of the diaphragm, the air in the predetermined space between the inner peripheral surface of the opening of the speaker frame and Is restricted by the sliding portion, and generation of unnecessary wind noise and the like is suppressed.

Further, a ring is attached to the outer peripheral end of the diaphragm while being accommodated in the inner peripheral surface of the opening of the speaker frame and maintaining a predetermined space, and is separated from the open end of the speaker frame. Since the outer peripheral surface of the end portion of the ring at the opened position is provided with the sliding portion that restricts the flow of air in the predetermined space between the inner peripheral surface of the opening of the speaker frame,
Along with the vibration of the diaphragm, the sliding part is kept in sliding contact with the inner peripheral surface side of the opening of the speaker frame, and the outer peripheral end of the diaphragm and the opening end of the speaker frame are arranged at substantially the same position. Since the space that is partitioned by the inner peripheral surface of the opening of the speaker frame does not occur on the front side of the diaphragm because it can be installed, when the sound wave generated by the vibration of the diaphragm exits the opening end of the speaker frame. Since the spread due to the diffraction phenomenon does not occur, the occurrence of the sound pressure decrease is suppressed.

Furthermore, since the sliding portion is formed of a porous member or a fibrous porous member, a slight air flow can be generated to the extent that sound quality is not deteriorated on the sliding surface, and sliding Since it is possible to avoid the adsorption phenomenon that occurs when the sliding contact portion between the sliding portion and the sliding surface is in a vacuum state, it is possible to maintain good slidability of the sliding portion.

Furthermore, since the lubricant is contained in the sliding portion formed of the porous member or the fibrous porous member, the retaining force of the lubricant is increased and the sliding property of the sliding portion is improved. Can be maintained.

Further, since the sliding portion made of the semi-closed cell material contains the lubricant, the retaining ability of the lubricant is further enhanced.

That is, the semi-closed bubbles have a characteristic that they are independent of the adjacent bubbles in the normal state and communicate with the adjacent bubbles when a pressure is applied. It is possible to allow the lubricant to permeate the entire sliding portion. Therefore, when the sliding part slides on the inner peripheral surface of the opening of the speaker frame, pressure is applied to the sliding part by the reaction force from the inner peripheral surface of the opening. Since it gradually exudes, the sliding surface of the sliding part with the inner peripheral surface of the opening is appropriately replenished with lubricant, and the slidability of the sliding part can be kept good for a long time. Becomes

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings described below, the same parts as those in FIGS. 4 to 6 are designated by the same reference numerals, and the duplicated description will be omitted.

[First Embodiment] FIG. 1 shows an embodiment of the edgeless speaker of the present invention. An elastic body such as rubber or foam rubber or a fibrous material is formed at the end of the ring 16. A sealing material 20 is attached as a deformable sliding portion made of a porous member. The sealing material 20 is arranged so as to seal the entire space (annular space) between the diaphragm 13 and the ring 16 as a vibrating member and the opening inner peripheral surface 9 a of the frame 9. As a result, even if a pressure change occurs inside the cabinet due to the vibration of the diaphragm 13, the annular space is sealed, so that the flow of air through the annular space is restricted. That is, the state in which the entire space (annular space) between the inner peripheral surface 9a of the opening is sealed is an unnecessary wind noise or the like generated due to a pressure change inside the cabinet due to the vibration of the diaphragm 13. The closed state means that the flow of air is restricted to the extent that the above does not occur.

In such a structure, when the diaphragm 13 vibrates, the sealing material 20 attached to the end of the ring 16 slides while elastically contacting the sliding surface which is the inner peripheral surface 9a of the opening of the frame 9. Therefore, the followability of the sealing material 20 to the sliding surface due to the vibration of the diaphragm 13 is improved, and as described above, the dimensional accuracy of the components such as the frame 9 and the ring 16 varies, and the dimensional change due to temperature change and the like. Even if they occur, the variations and the dimensional changes can be absorbed by the elastic contact of the seal member 20 by the urging force of the seal member 20 to the sliding surface side. Even if the sealed state is maintained and the pressure inside the cabinet changes due to the vibration of the diaphragm 13, air does not flow in the sliding contact portion, so that an unnecessary wind noise is generated. Sound quality by Reduction is suppressed.

[Second Embodiment] In the second embodiment, in FIG. 1, the outer peripheral end 15 of the diaphragm 13 and the opening end 9b of the frame 9 are placed in a stationary state. And the vibration plate 13
The ring 16 attached to the outer peripheral end 15 of the
The outer peripheral end 15 of the diaphragm 13 is attached to the outer peripheral end 15 of the diaphragm 13 while being housed on the inner peripheral surface 9a side of the opening of the frame 9 so as not to be exposed to the outside from the outer peripheral end 9b of the diaphragm 13. By attaching to the outer peripheral end of the ring 16 on the side opposite to the part to which 15 is attached, the expansion from the opening end 9b due to the diffraction phenomenon of sound waves is suppressed.

Therefore, in this embodiment, even if the vibrating plate 13 vibrates to the maximum extent of the vibrating range and the outer peripheral end 15 of the vibrating plate 13 protrudes from the opening end 9b of the frame 9, the seal is sealed. The material 20 is the inner peripheral surface 9 of the opening of the frame 9.
Since it is arranged so as to be left on the a side, the sealing material 2
The sliding contact state with the inner peripheral surface 9a of the opening of the frame 9 of 0 is maintained, and the vibration operation of the diaphragm 13 is smoothly performed.

[Third Embodiment] In the third embodiment, the sealing material 20 of FIG. 1 is formed of a porous member such as foamed rubber, and the sliding contact portion between the sealing material 20 and the sliding surface is formed. By avoiding the adsorption phenomenon that occurs in a vacuum state, the slidability of the sealing material 20 is kept good.

That is, as described above, in order to suppress the generation of the sliding noise, the sliding surface which is the inner peripheral surface 9a of the opening of the frame 9 is mirror-finished to enhance the smoothness and to slide. It is considered that the generation of sound is suppressed, but conversely, by performing mirror surface treatment, the sliding contact portion between the sealing material 20 and the sliding surface that is the inner peripheral surface 9a of the opening of the frame 9 becomes a vacuum state and is sucked. A phenomenon may occur, and the sliding operation of the sealing material 20 may not be performed smoothly.

Therefore, by forming the sealing material 20 with a porous member, when the sealing material 20 slides, a slight air flow is generated to the extent that sound quality is not deteriorated on the sliding surface. Therefore, it is possible to avoid an adsorption phenomenon that occurs when the sliding contact portion between the sealing material 20 and the sliding surface is in a vacuum state, and the slidability of the sealing material 20 can be kept good. In addition, the porous member has the advantages that, despite its elasticity, not only the friction with the sliding surface during sliding can be reduced but also the weight can be reduced. Even more smoothly.

[Fourth Embodiment] In the fourth embodiment, the sealing material 20 of FIG. 1 is formed of a fibrous porous member, and the sliding contact portion between the sealing material 20 and the sliding surface is vacuum. By avoiding the adsorption phenomenon that occurs in this state, the slidability of the sealing material 20 is maintained in the same manner as described above.

That is, although the fibrous porous member has elasticity, it has an advantage of reducing friction with the sliding surface when sliding, and the sealing material 20 is made of a fibrous porous member. By forming it, it is possible to cause a slight air flow to the extent that the sound quality does not deteriorate on the sliding surface when the sealing material 20 slides. It is possible to avoid an adsorption phenomenon that occurs when the sliding contact portion is in a vacuum state, to maintain good slidability of the sealing material 20, and to reduce the friction with the sliding surface to reduce the weight. Therefore, the diaphragm 13
The vibration operation of can be performed more smoothly.

[Fifth Embodiment] In the fifth embodiment, the sealing material 20 of FIG. 1 is formed of a porous member or a fibrous porous member, and a lubricant such as wax, grease, oil or the like is used. Is included to enhance the holding power of the lubricant. That is, since the porous member or the fibrous porous member is porous, it has a high ability to retain the lubricant contained therein and enhances the ability to retain the lubricant, so that the sealing material 20 slides on the sliding surface. It is possible to maintain the goodness.

[Sixth Embodiment] In the sixth embodiment, the sealing material 20 shown in FIG. 1 is formed of a semi-closed cell material, and a lubricant is contained therein to improve the ability to retain the lubricant. It is intended to be even higher.

That is, as shown in FIG. 2, the semi-closed bubbles are independent from the adjacent bubbles 30 because the bubble walls 31 are joined together in the normal state. On the other hand, when a pressure is applied, as shown in FIG. 3, the bubble walls 31 of the respective bubbles 30 are released from the joined state, and the adjacent bubbles 30 have a communication state. Therefore, when the sealant 20 contains a lubricant, it is possible to allow the lubricant to permeate into the sealant 20 as well by performing the process under pressure.

Further, by applying an appropriate pressure to the sealing material 20 containing the lubricant, the joined state of the bubble walls 31 of the respective bubbles 30 is released, and the movement of the lubricant between the bubbles 30 is prevented. As a result, the lubricant is appropriately exuded onto the surface of the sealing material 20. Further, by releasing the pressure on the sealing material 20, the respective bubble walls 31 of the respective bubbles 30 are joined, and the individual bubbles 30 are in an independent state, so that the retaining ability of the lubricant is also enhanced.

By the way, in the case of independent bubbles, since there is no communicating portion between adjacent bubbles, the lubricant does not move between the adjacent bubbles. It is not possible to cause the seeping of the sealing material 20 to the sliding contact surface.

On the other hand, in the case of continuous bubbles, the bubbles are always in communication with each other, so that the bubbles volatilize from the surface of the sealing material 20 and the ability to retain the lubricant decreases.

The lubricant is preferably grease-like. The reason is that it is less volatile than oil-like substances and does not lose weight for a long period of time. By the way, when wax is used, it is difficult to apply it to the sealing material 20 or to contain it, and since it does not exude to the sliding contact surface of the sealing material 20 unlike a grease-like lubricant, it can be used for a long time. At this time, since it becomes difficult to hold the wax applied to the sliding contact surface, the vibration state of the diaphragm 13 may not be properly performed.

Further, in the case of the grease-like lubricant, since the unevenness of the sliding contact surface of the sealing material 20 can be filled to be flat, the airtightness with the sliding surface which is the inner peripheral surface 9a of the opening of the frame 9 is obtained. Can be increased. Further, in the case of the grease-like lubricant, since it has a viscous effect, it is possible to suppress the vibration of the frame 9 and the seal material 20.

Therefore, in this embodiment, the sealing material 20 containing the lubricant is the inner peripheral surface 9 of the opening of the frame 9.
When sliding a, pressure is applied to the sealing material 20 by the reaction force from the opening inner peripheral surface 9a, so that the lubricant contained in the sealing material 20 is applied to the sliding contact surface side with the opening inner peripheral surface 9a. Since it oozes out gradually, the lubricant is appropriately replenished between the sliding contact surface of the sealing material 20 and the inner peripheral surface 9a of the opening, and the slidability of the sealing material 20 is kept good for a long period of time. It becomes possible.

[0045]

As described above, according to the edgeless speaker of the present invention, the vibrating member including the vibrating plate is provided in the predetermined space between the vibrating plate and the inner peripheral surface of the opening of the speaker frame at the outer peripheral end. Since a sliding part that slidably contacts the inner peripheral surface of the opening while restricting the flow of air, the inner peripheral surface of the opening of the speaker frame is closed even when a pressure change occurs inside the cabinet due to the vibration of the diaphragm. The flow of air in a predetermined space between and is restricted by the sliding portion, and generation of unnecessary wind noise and the like is suppressed.

Further, a ring is attached to the outer peripheral end of the diaphragm while being housed in the inner peripheral surface of the opening of the speaker frame and maintaining a predetermined space, and is separated from the open end of the speaker frame. Since the outer peripheral surface of the end portion of the ring at the opened position is provided with the sliding portion that restricts the flow of air in the predetermined space between the inner peripheral surface of the opening of the speaker frame,
Along with the vibration of the diaphragm, the sliding part is kept in sliding contact with the inner peripheral surface side of the opening of the speaker frame, and the outer peripheral end of the diaphragm and the opening end of the speaker frame are arranged at substantially the same position. Since the space that is partitioned by the inner peripheral surface of the opening of the speaker frame does not occur on the front side of the diaphragm because it can be installed, when the sound wave generated by the vibration of the diaphragm exits the opening end of the speaker frame. Since the spread due to the diffraction phenomenon does not occur, the occurrence of the sound pressure decrease is suppressed.

Further, since the sliding portion is formed of the porous member or the fibrous porous member, a slight air flow that does not cause sound quality deterioration on the sliding surface can be generated, and sliding Since it is possible to avoid the adsorption phenomenon that occurs when the sliding contact portion between the sliding portion and the sliding surface is in a vacuum state, it is possible to maintain good slidability of the sliding portion.

Furthermore, since the lubricant is contained in the sliding portion formed of the porous member or the fibrous porous member, the retaining force of the lubricant is increased and the sliding property of the sliding portion is improved. Can be maintained.

Further, since the sliding portion made of the semi-closed cell material contains the lubricant, the retaining ability of the lubricant is further enhanced. Therefore, the generation of unnecessary wind noise and the like are suppressed, the generation of the sound pressure decrease and the like are suppressed, and the slidability of the sliding portion is improved, so that the sound quality can be improved.

[Brief description of drawings]

FIG. 1 is a half-cut sectional view showing an embodiment of an edgeless speaker of the present invention.

FIG. 2 is an enlarged cross-sectional view showing bubbles when the sealing material of FIG. 1 is semi-closed bubbles.

FIG. 3 is an enlarged cross-sectional view for explaining the action of the semi-closed bubbles in FIG.

FIG. 4 is a half-cut sectional view showing a conventional edgeless speaker.

5 is a half sectional view for explaining a case where a sealing material is provided on the edgeless speaker of FIG.

6 is a half-cut sectional view for explaining another conventional example when the configuration of the edgeless speaker in FIG. 5 is changed.

[Explanation of symbols]

 9 Frame 9a Opening Inner Surface 13 Vibration Plate 16 Ring 20 Sealing Material 30 Bubble 31 Bubble Wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takashi Oyaba Takashi Oyaba 26-10 Hanazono, Tokorozawa, Saitama Pioneer Co., Ltd. Tokorozawa Plant (72) Inventor Shunichi Takahashi 426-10 Hanazono, Tokorozawa, Saitama Pioneer shares Inside the company Tokorozawa factory (72) Inventor Zhang Qingao 2610 Hanazono, Tokorozawa, Saitama Prefecture Pioneer Co., Ltd.Tokorozawa factory (72) Inventor Yoko Sato 42610 Hanazono, Tokorozawa city, Saitama Pioneer Co., Ltd. Tokorozawa factory (72) Inventor, Kun Kumada, 426-10 Hanazono, Tokorozawa, Saitama Prefecture, Tokorozawa Plant, Pioneer Co., Ltd. (72) Junko Oba, 2626, Hanazono, Tokorozawa, Saitama Prefecture, Tokorozawa Plant, Pioneer Co., Ltd. (72) Inventor Shinji Oyano 426-10 Hanazono, Tokorozawa, Saitama Prefecture Pioneer Corporation Tokorozawa Plant Inside

Claims (6)

[Claims] 1. An edgeless speaker in which an outer peripheral end of a diaphragm is movable along an inner peripheral surface of an opening of a speaker frame while maintaining a predetermined space, the outer peripheral end of the diaphragm and the speaker. A vibrating member including the vibrating plate is provided with a sliding portion that slidably contacts the inner circumferential surface of the opening while restricting air flow in a predetermined space between the inner circumferential surface of the frame and the opening. Edgeless speaker that does. 2. An outer peripheral end of the diaphragm and an opening end of the speaker frame are arranged on substantially the same plane, and a predetermined space is maintained between the diaphragm and the inner peripheral surface of the opening of the speaker frame. While being an edgeless speaker in which the outer peripheral end of the diaphragm is movable along the inner peripheral surface of the opening, the outer peripheral end of the diaphragm is housed on the inner peripheral surface side of the opening of the speaker frame. A ring is attached while maintaining the predetermined space, and a predetermined space between the ring and the inner peripheral surface of the opening of the speaker frame is provided at a position distant from the opening end side of the speaker frame in the ring. An edgeless speaker, which is provided with a sliding portion that restricts the flow of air. 3. The edgeless speaker according to claim 1, wherein the sliding portion is formed of a porous member. 4. The edgeless speaker according to claim 1, wherein the sliding portion is formed of a fibrous porous member. 5. The edgeless speaker according to claim 1, 2, 3, or 4, wherein the sliding portion contains a lubricant. 6. The edgeless speaker according to claim 1, wherein the sliding portion is made of a semi-closed cell material and contains a lubricant.