JP3376329B2 - Vibrating membrane and flat speaker - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating film for giving a tensile tension to vibrate and a flat speaker capable of vibrating and driving the vibrating film with a slight driving force.

[0002]

2. Description of the Related Art FIG. 15 is a vertical sectional view showing an example of a conventional flat speaker. A flat panel speaker 1 shown in the same figure drives a flat plate-shaped vibrating membrane 2 from the back side by a voice coil type exciter (exciter) 3. Shaker 3
Is composed of a voice coil 5 having one end bonded to the center of the back surface of the vibrating membrane 2 via a piston plate 4, a columnar magnet 6 coaxially arranged on the other end side of the voice coil 5, and the like. The columnar magnet 6 is housed in a bottomed cylindrical yoke 7 with a collar, and a dish-shaped back plate 8 for holding a buffer sleeve 7 a fitted in the cylindrical portion of the yoke 7.
The peripheral portion of the vibrating membrane 2 is fixed to the support frame 9 assembled to the peripheral portion of the vibrating membrane 2 via a ring-shaped gasket 9a for maintaining the membrane shape. The voice coil 5 is connected to the flange portion of the yoke 7 by a damper 10 whose one end is connected to its side surface. The conventional vibrator 3 moves the piston plate 4 in the front-back direction by the Fleming force generated in the voice coil 5 when the voice coil 5 in the magnetic field formed by the columnar magnet 6 is excited by the voice current. The vibrating membrane 2 that is driven and vibrates generates sound pressure.

[0003]

In the conventional flat speaker 1 described above, the vibrating membrane driving capability of the vibrator 3 is a columnar magnet 6.
Is proportional to the generated magnetic force and the number of coil turns of the voice coil 5, so that the weight of the vibrating membrane 2 is reduced if the sound pressure required for practical use is secured without changing the specifications of the voice coil 5 and the columnar magnet 6. It was the only one. this is,
This is because, in order to efficiently transfer the applied vibration energy to the atmosphere, it is necessary to statically move the vibrating membrane 2 back and forth in the front-rear direction while maintaining a flat surface in the largest possible area. Weight reduction of 2 has been a major mission for speaker developers. However, a vibrating membrane suitable for weight reduction generally means the use of an expensive membrane material,
Since the more expensive the film material is, the lower the workability is, so that the vibrating film 2 having a certain weight is inevitably used, and the output sound pressure level in that case is about 70 to 80 dB / W. In order to obtain the above sound pressure, a power amplifier serving as a driving source needs an amplifier having an output of 10 W or more. Thus, the conventional flat speaker 1 is, for example, several tens of meters.
It is completely impossible to use it by directly connecting it to the headphone output terminal of a portable audio device with about W output, and in reality it is not possible to use it outdoors, assuming battery operation. there were.

Further, in the conventional flat speaker 1, the peripheral edge of the vibrating membrane 2 is supported by the support frame 9 via the ring-shaped gasket 9a for maintaining the membrane shape, but the gasket 9a itself vibrates the vibrating membrane 2. It is assumed that the vibrating membrane 2 has only four free sides from the driving principle, since the minimum necessary membrane shape maintaining force is given so as not to impede the load or give an extra load. Is manufactured in. For this reason, after a certain period of use, the rigidity gradually decreases due to moisture or the like absorbed from the outside air, and as a result, a part thereof slightly warps or bends, and accurate piston vibration of the vibrating membrane 2 cannot be expected. The periphery of the vibrating membrane 2 touches the surroundings to cause flicker, or the deformed portion presses the voice coil 5 to hinder the operation of the vibration exciter 3. In an extreme case, the voice coil 5 is a magnetic circuit. There was a problem that the reproduced sound gradually became uncut and it was easy to lose the vividness, such as when it made contact with and made a sliding sound. Also,
Such warpage or slack occurring in the vibrating membrane 2 is caused by the fact that the acting gravity or external stress is different between the upper and lower sides and the left and right sides, in addition to the reason that the environments such as temperature and humidity received on the front and back sides of the vibrating membrane 2 are different. However, the conventional flat speaker 1 has a problem that there are many factors that hinder constant stable reproduction.

Furthermore, in the conventional flat speaker 1, the piston plate 4 at the tip of the vibrator 3 is fixed to the back surface of the vibrating membrane 2 by adhesion or the like, and the time required for assembly including the time required for adhesion is increased. Since the piston plate 4 is long and adheres to the vibrating membrane 2 with a certain adhesive area, the vibration of the vibrating membrane 2 is easily regulated by the piston plate 4, and the damper 10 that connects the voice coil 5 to the yoke 7 does not vibrate. Since the strength to withstand the weight of the membrane 2 is required, it is easy to hinder the light movement of the voice coil 5, and the piston plate 4
To absorb the posture deviation when fixing the
It is necessary to secure a certain amount of room for the voice coil 5 to incline the axis, and therefore the magnetic gap between the voice coil 5 and the magnetic circuit surrounding it cannot be minimized, and the magnetic efficiency is maximized. It was difficult to do so. Further, since the vibration exciter 3 is fixed to the vibrating membrane 2, even if a plurality of vibrating membranes 2 having different patterns and patterns printed on the surface are provided as options, the vibrating membrane 3 is provided. The vibrating membrane 2 must be replaced in this state, and only the vibrating membrane 2 cannot be removed and replaced.
There was a problem that the replacement cost increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to drive a prismatic vibrating membrane to which tension is applied so as to achieve constant stable reproduction and improve sound pressure. Is.

[0007]

In order to achieve the above object, a vibrating membrane of the present invention according to claim 1 has a polygonal vibrating membrane portion vibrating by vibrating from the outside, and each of the vibrating membrane portions. And a fixed film part that is formed integrally with each side independently of each other and extends toward the peripheral side, and that supports and fixes the vibrating film part in a state in which a tensile tension is applied. .

Further, the vibrating film portion and the fixed film portion are made of polyethylene terephthalate or a metal vapor-deposited polyethylene terephthalate, or the vibrating film portion and the fixed film portion are made of a polyethylene naphthalate or a metal vapor-deposited polyethylene naphthalate. Another feature is that the vibrating film portion and the fixed film portion are made of carbon fiber.

The vibrating membrane of the present invention according to claim 6 is
A rectangular vibrating membrane part formed by forming rectangular cutouts at four corners of a square film material and surrounded by a line connecting the cut apexes of the cutouts or a line passing therethrough, And a fixed film part formed of a region excluding the vibrating film part from the molded film material. Further, the vibrating membrane of the present invention according to claim 14 is a quadrangular vertical membrane in which fixed membrane portions are arranged above and below the vibrating membrane portion, and a rectangular horizontal membrane in which fixed membrane portions are arranged on the left and right sides of the vibrating membrane portion, A liquid that is interposed between the vibrating membrane portions of the transverse membrane and the vibrating membrane portions of the vertical membrane in a state of being overlapped with each other, and combines the vibrating membrane portions with each other by surface tension. Is.

The flat speaker of the present invention according to claim 5 is
The vibrating film according to any one of claims 1 to 4, a support frame that supports and fixes the fixed film portion of the vibrating film, and the vibrating film portion of the vibrating film supported by the support frame. A tension tension urging means for urging a tension tension from the central portion to the peripheral portion, and a force applied to vibrate and drive the vibrating membrane by being supported by the support frame and contacting the back surface of the vibrating membrane of the vibrating membrane. And a shaker.

The flat speaker of the present invention according to claim 7 is
The vibrating membrane according to claim 6, a support frame having a rectangular frame shape for supporting and fixing the fixed membrane portion of the vibrating membrane, upper and lower sides and left and right sides of the vibrating membrane portion of the vibrating membrane supported by the support frame. Tensile tension urging means for individually applying tensile tension to the sides in the separating direction, and a support frame, which is supported by the support frame and abuts against the back surface of the vibrating membrane portion of the vibrating membrane to vibrate and drive the vibrating membrane portion. And a vibration exciter.
A flat speaker according to a fifteenth aspect of the present invention is the vibrating membrane according to the fourteenth aspect, and a square frame-shaped support frame that supports and fixes each fixing film portion of the vertical film and the horizontal film of the vibrating film. Tension tension urging means for urging tension on the vibrating membrane portion of the vertical membrane with respect to the vibrating membrane supported by the support frame in the up-down direction and in the vibrating membrane portion of the horizontal membrane in the left-right direction,
A vibrating device that is supported by the support frame and abuts against a back surface of the vibrating film portion of the vibrating film to vibrate and drive the vibrating film portion.

Furthermore, in the flat speaker of the present invention according to claim 7 or claim 15, the tensile tension urging means is projectingly provided on an inner edge portion of the support frame and abuts on the fixed film portion. A fret for partitioning and forming a vibrating end, an engaging groove formed in the support frame, and a part of a fixed film portion of the vibrating film engaging with the engaging groove to be locked in the engaging groove. Each of the supporting frame and a fret, which comprises a clip member, or the pulling tension urging means is projectingly provided on an inner edge portion of the supporting frame and abuts against the fixed film portion to define a vibrating end. It is an adjusting screw that is interposed in the side connecting portion and variably adjusts the connecting distance, or the tensile tension urging means is
A fret protruding from the inner edge of the support frame and abutting against the fixed film portion to partition and form a vibrating end, and a fixed film portion of the vibrating film that is heat-formed and contracts when heated to the support frame. It is characterized by comprising a welded portion to be welded. Alternatively, in the flat speaker of the present invention according to claim 7, the vibrating membrane according to claim 6 has a heat shrinkability only in a specific uniaxial direction, and the vibrating film is provided in two orthogonal axes oblique to the specific uniaxial direction. The tensile-tension urging means is formed from a rectangular film material partitioned by four parallel sides, and the tensile-tension urging means projects from the inner edge of the support frame to support the fixed film portion of the vibrating film on the support frame. When the vibrating membrane is heated and shrunk in a fixed state, it is provided with a fret which is in close contact with the fixed membrane portion and tensions the vibrating membrane in the orthogonal biaxial directions to partition the vibrating end. Is.

Further, at least the vibrating film portion is made of a transparent film or a semi-transparent film that allows light to pass therethrough, and the vibration exciter is disposed near the periphery of the vibrating film portion, or At least the vibrating film part is made of an opaque film that does not transmit light, and the vibrator is arranged near the center of the vibrating film part.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 (A), (B)
FIG. 2A is a perspective view and an exploded perspective view showing a schematic configuration of a first embodiment of a flat panel speaker of the present invention, FIG.
(B) and (C) are respectively a front view, a vertical cross-sectional view and a rear view of the flat speaker shown in FIG. 1, and FIG. 3 is an enlarged cross-sectional view of an essential part of the flat speaker shown in FIG. ), (B),
8C, 8 </ b> A, 8 </ b> B, and 8 </ b> C are exploded perspective views, front views, and main parts, respectively, showing schematic configurations of the second to sixth embodiments of the flat panel speaker of the present invention. Enlarged sectional view,
9 (A), (B), and (C) are front views, side views and bottom views of main parts, which are modifications of the flat speaker shown in FIG. 8, respectively, and FIGS. FIG. 11 is a front view showing another modification of the flat speaker shown in FIG. 8 and an explanatory view of a vibrating film cutting method, and FIG. 11 is an exploded perspective view showing a schematic configuration of a seventh embodiment of the flat speaker of the present invention. FIG. 12, a front view and a cross-sectional view, FIG. 12 is a schematic perspective view showing an application example of the flat speaker shown in FIG. 11, and FIG. 13 shows another application example of the modification of the flat speaker shown in FIG. 14A and 14B are respectively a front view and a side view showing another embodiment of the vibrating membrane of the present invention.

A flat speaker 1 shown in FIGS. 1 (A) and 1 (B).
Reference numeral 1 denotes a rectangular vibrating membrane 1 called a tensed diaphragm.
The four sides of 2 are supported by a support frame 13 having a rectangular frame shape, and the vibrating membrane 1
The center of the rear surface of 2 is driven by a vibrator 14 to drive a piston to generate sound. The vibrating membrane 12 is, for example, PEN (polyethylene naphthalate), PET (polyethylene terephthalate), a metal vapor-deposited material thereof, or a material such as carbon fiber is formed into a square-shaped membrane having a size covering the front surface of the support frame 13. Use one. That is, by using a synthetic resin material or synthetic fiber suitable for film processing and a film material having high tensile strength as the vibration film 12, stable vibration characteristics can be maintained for a long period of time. Particularly, when a film material having high tensile rigidity such as metal-deposited PEN or PET is used, stable vibration characteristics with almost no deterioration over time can be constantly maintained. In addition, since the formed rectangular film is used by applying tensile tension from four directions, the four corners are notched in a rectangular shape, and when focusing on the function of each part, a line connecting the notch vertices of each notch or the A rectangular vibrating membrane portion 12 surrounded by a line passing through the neighborhood and having a predetermined aspect ratio.
The function can be classified into a and a fixed film portion 12b formed of the remaining area of the formed film material excluding the vibrating film portion 12a.
The fixed film portion 12b is fixed to the support frame 13, and the vibrating film portion 1
2a is supported under tension.

By the way, when it is assumed that the central portion of the back surface is driven as a point sound source, the vibrating membrane portion 1 having the rectangular shape is used.
The difference in acoustic characteristics based on the shape difference between 2a and the circular vibrating membrane (not shown) is clear. That is, since the distance from the point sound source to the peripheral portion is different for each azimuth in the square-shaped vibrating membrane portion 12a, like the circular diaphragm in which the distance from the point sound source to the peripheral portion is the same in all directions. It does not show the resonance characteristic that it resonates remarkably at one frequency, and has a large number of resonance frequencies. Therefore, the square-shaped vibrating membrane portion 12a has a sufficiently wider reproduction frequency band than the circular vibrating membrane, and the vertical tension applied to the upper and lower sides and the lateral direction applied to the left and right sides. By independently adjusting the tensile tensions of (1) and (2), desired frequency characteristics can be freely realized, and many advantages derived from the film shape can be effectively utilized for the acoustic effect.

As shown in FIGS. 2B and 2C, the vibrator 14 has a piston plate 15a at the center of the back surface of the vibrating membrane 12.
Voice coil 15 having one end abutting through it, a caldera volcano-shaped yoke 16 having an inverted E-shaped cross section coaxially arranged on the other end side of the voice coil 15, and an intermediate portion of the annular portion of the yoke 16. It is composed of an annular magnet 17 sandwiched between and a damper 18 that connects the side surface of the voice coil 15 and the end of the yoke 16. The vibration exciter 14 is configured to thoroughly improve the efficiency by strengthening the magnetic force, minimizing the magnetic gap, reducing the friction of the damper, and so on. The voice coil 15 in the magnetic field formed by the annular magnet 17 along the yoke 16 When a voice current is applied, the voice coil 15
The voice coil 15 vibrates in the axial direction by the Fleming's force generated in the, and the piston plate 15a is driven in the front-rear direction.

Further, the piston plate 15a is not adhered to the vibrating membrane 12, but is simply brought into contact with the center of the back surface of the vibrating membrane 12. Therefore, the vibrator 14 needs to be separately held on the back surface side of the vibrating membrane 12. Therefore, in the present embodiment, a pair of presser bars 19 that intersect in an X shape are used, the back surface of the yoke 16 is fixed to the intersections of the presser bars 19, and the ends of the presser bars 19 are supported by the support frame. It is fixed to the four corners of 13. Thus, the vibrator 14 is pressed and held at the center of the back surface of the vibrating membrane 12. In order to adjust the axis of the voice coil 15 orthogonally to the vibrating membrane 12, a skew adjusting mechanism (not shown) for adjusting the swinging angle of the vibrator 14 with respect to the pressing rod 19 is incorporated at the intersection of the pressing rod 19. is there.

The support frame 13 is constructed by connecting the upper side portion, the lower side portion, the left side portion and the right side portion into a rectangular frame shape. At each side, as shown in FIG. 2 (A) or FIG. 3, a fret 20 having a semicircular cross section is provided so as to protrude toward the inner edge side,
Further, a band-shaped frill 21 for fixing the edge portion of the vibrating membrane 12 is fixed to the outer edge side. Furthermore, in the case of the present embodiment, U is provided at the center of each of the lower side and the right side of the support frame 13.
Clip rods 2 each having an elliptical cross section are formed with engaging grooves 22 having a V-shaped cross section in the longitudinal direction.
3 is engaged to apply tension to the vibrating membrane 12. That is, in the case of the present embodiment, the fret 20, the engaging groove 22, and the clip rod 23 constitute a tension tension urging means for applying a tension tension to the vibrating membrane 12 from the central portion to the peripheral portion. Height and engagement groove 2
The height of 2 and the engagement depth of the clip rod 23 with respect to the engagement groove 22 influence the tensile tension.

When assembling the flat speaker 11,
First, the corresponding edge portions of the fixed film portion 12b of the vibrating membrane 12 are glued and bonded to the strip-shaped frills 21 on the left side portion and the upper side portion of the support frame 13. Next, the vibrating membrane 12 is pulled flat, and the corresponding edge portions of the fixed membrane portion 12b of the vibrating membrane 12 are glued and adhered to the strip-shaped frills 21 on the right side portion and the lower side portion of the support frame 13. However, in this state, only a slight tension is applied to the vibrating membrane 12, and it can be said that the vibrating membrane 12 is slightly loosened rather than in a tensioned state. Therefore, the two clip rods 23 are taken out and engaged with the respective engaging grooves 22 on the right side and the lower side of the support frame 13 from above the vibrating membrane 12. As a result, the vibrating membrane 12 that has been stretched with slack until then is pulled in the left-right direction and the up-down direction according to the pushing amount of the clip rod 23,
As shown in FIG. 2 (A), they are stretched with a constant tension. In this case, the tension in the left-right direction and the tension in the up-and-down direction can be arbitrarily adjusted according to the pushing amount of the corresponding clip rod 23, and as described above, the tension in the left-right direction and the up-and-down tension of the vibrating membrane 12 are mutually different. By independently adjusting, desired frequency characteristics can be freely realized.

When the assembly of the vibrating membrane 12 to the support frame 13 is completed in this manner, the end portions of the pair of pressing rods 19 to which the vibration exciter 14 is fixed at the intersections are next attached to the four corners on the rear surface side of the support frame 13. Secure with screws. In that case, shaker 1
The piston plate 15a at the tip of the voice coil 15 of No. 4 comes into contact with the center of the back surface of the vibrating membrane 12, but since the vibrating membrane 12 itself is pulled vertically and horizontally, the vibrating membrane 12 at the portion with which the piston plate 15a comes into contact It is advisable to assemble them so that they come into contact with each other with a pressing force that causes a displacement of about 1/2 of the maximum amplitude. In addition, with the skew adjustment mechanism, the pressing rod 1
Since the swinging angle of the vibration exciter 14 with respect to 9 can be freely adjusted, an adjustment jig (not shown) or the like can be used to adjust the piston plate 15
It can be adjusted so that a vibrates in a direction perpendicular to the vibrating membrane 12.

When a voice current is applied to the voice coil 15, the flat speaker 11 having the above-described structure generates a Fleming force according to the magnitude of the current and the number of coil turns, and the piston plate 15a causes the vibrating membrane 12 to move forward and backward. Sound pressure is generated when the piston is driven. In this case, the vibrating membrane 12
Since it is given tension by itself and vibrates with a slight pressing drive force, sufficient sound pressure can be generated only by supplying a minute drive current. Therefore, for example, in the case of the vibrating membrane 12 having an area of about A4 size,
The output signal of the headphone output terminal can be directly energized and driven to the voice coil 15 without passing through the amplifier. According to the experimental results, it is known that the sound pressure improving effect of the vibrating membrane 12 to which the tensile tension is applied exceeds several dB, and the sound pressure improving effect of several dB accompanying the combined use of the high-sensitivity vibrator 14 is shown. Together, it is possible to improve the sound pressure of the flat speaker 11 as a whole by about ten and several dB. Specifically, in the case of a conventional free-edge type flat speaker, an A6 version size diaphragm that was driven through a power amplifier of about 1.2 W output that amplifies headphone output is applied to the diaphragm 12 with tension. Flat speaker 11 driven in the open state
It has been confirmed that can be directly driven with headphone output, and the reproduced sound obtained has the same sound pressure, frequency characteristics, and distortion rate. Further, in the case of the conventional free-edge type flat speaker, the A3 size diaphragm that was driven via the power amplifier of about 10 W output that amplifies the headphone output is also driven with tension applied to the diaphragm 12. The flat panel speaker 11 can be driven by amplifying the headphone output with a power amplifier of about 1 W output capable of battery driving about 4 AA batteries, and can be driven by a power cord without external power supply to the flat panel speaker. Has been confirmed.

As described above, the flat speaker 11 has the support frame 13 in which the four sides of the rectangular vibrating membrane 12 with the four corners cut out are individually applied to the upper and lower sides and the left and right sides in the separating direction. Since the vibrating membrane 12 is vibrated and driven by the vibrating device 14 supported on the back surface of the vibrating film 12, the distance from the driving point of the vibrating device 14 to the peripheral portion changes in accordance with the direction. As a characteristic of the vibrating membrane 12, a sufficiently wide reproduction frequency band can be obtained due to the presence of a large number of resonance frequencies. Further, the rectangular vibrating membrane 12 has tensile tensions in upper and lower sides and left and right sides which are individually pulled in the separating direction. The desired frequency characteristic can be realized by providing the above, and since the four corners of the vibrating membrane 12 are notched, the tensile tension in the vertical direction and the tensile tension in the horizontal direction are mutually Without interfering, it is possible to variably set freely.

The piston plate 15a at the tip of the vibrator 14
Does not need to be fixed to the back surface of the vibrating membrane 12 and can be simply brought into contact with the vibrating membrane 12. Therefore, the time required for assembling the flat speaker 11 is short, and the piston plate 15a regulates the vibration of the vibrating membrane 12. There is no. Also, the vibrating film 1
Since No. 2 is supported by being pulled in all directions, the damper 18 connecting the voice coil 15 to the yoke 16 does not need strength, and the damper 18 does not hinder the light movement of the voice coil 15. Further, since there is no posture deviation when the piston plate 15a is brought into contact with the vibrating membrane 12, it is not necessary to secure a room for the axial inclination of the voice coil 15, whereby the voice coil 5 and the magnetic circuit surrounding the voice coil 5 can be secured. The magnetic gap between and can be minimized, and the magnetic efficiency can be maximized. Thus, the vibrating membrane 12 biased by tensile tension can be a sufficient vibration source even if it is lightweight, and can generate a sufficient volume with a small driving force. Therefore, the flat speaker 11 can be directly connected to a headphone output terminal attached to an audio device or a video device and can be directly driven, whereby a speaker for a portable AV device that does not require a special power amplifier. For example, by finishing the speaker into an outer shape of a plastic case that accommodates a CD (compact disc), for example, full-scale sound reproduction at a travel destination is possible.

Further, the vibrating membrane 12 is in a tensioned state, and the supporting frame 13
The flat shape is damaged by the moisture absorption effect with the progress of use like the conventional flat speaker 1 whose peripheral portion is a free end, and the piston vibration cannot be expected and the reproduced sound is refined. There is no lack of
High-quality reproduction characteristics can be constantly maintained, and the vibrator 14 that drives the vibrating membrane 12 is only brought into contact with the vibrating membrane 12 at the driving point. When a plurality of vibrating membranes 12 with different patterns or a vibrating membrane 12 to which a photograph is freely attached are prepared, the user selects one of these vibrating membranes 12 and the vibrator 14 remains the same. It is also possible to replace only the vibrating membrane 12, and in consideration of use as a photo stand or upholstery, it is possible to provide an end-user-oriented usability while suppressing replacement costs.

In the first embodiment, the support frame 13
4A to 4C, the tension is applied to the vibrating membrane 12 by the clip rod 23 that engages with the right side portion and the lower side portion of FIG.
As in the flat speaker 31 shown in FIG. 3C, the four sides of the vibrating membrane 32 may be fixed to the support frame 33 by using the clip frame 34 integrated in a square shape. In addition,
In the case of the second embodiment, a fret 35 is projected in a square frame shape on the inner edge side of the support frame 33, and the height of the fret 35 and the engagement of the clip frame 34 with the annular engagement groove 36 of the support frame 33. The tension applied to the vibrating membrane 32 can be adjusted according to the depth. The four sides of the clip frame 34 are integrated into a frame shape, but since the connecting portions on the adjacent sides have some flexibility, the vertical and horizontal directions are within the bending limit of the connecting portion. It is possible to adjust the tension independently of each other. Further, the vibrating membrane 32 shown in the present embodiment
Is terminated with a highly flexible wire 32d along the contour shape before the notches are formed at the four corners. Since the wire 32d is integrated with the ridge line portion of the vibrating membrane 32 except for the cutout portion, and the shape of the cutout portion before cutting is maintained, the vibrating membrane 32 is not attached to the support frame 33. In this case, the fret 35 can be used as a guide for alignment. Further, even if a step is generated because the engagement depth of the clip frame 34 with respect to the engagement groove 36 is different on each side of the support frame 33, the wire 32d corresponding to the cutout portion is flexibly deformed to correspond to the step. be able to.

In the first and second embodiments, the height of the frets 20 and 35 and the clip rod 23 and the clip frame 3 are set.
The tension applied to the vibrating membranes 12 and 32 is adjusted in accordance with the pushing depth of 4 in FIGS. 5 (A), 5 (B),
As in the flat panel speaker 41 of the third embodiment shown in (C), a rectangular frame-shaped washer 46 is applied to each side of a support frame 43 having a square frame-shaped fret 45 protruding from the front along the inner peripheral edge. Alternatively, the vibrating membrane 42 may be fixed by a tightening screw 44 that is screwed into the central portion of each side.
In the case of the present embodiment, the tensile tension applied to the vibrating membrane 42 can be adjusted by the drilling position of the screw insertion hole 42a bored in the vibrating membrane 42. That is, in the case of the present embodiment, the fret 45, the tightening screw 44, and the screw insertion hole 42a constitute a pulling tension urging means, and if the interval between the screw insertion holes 42a on the upper and lower sides or on the left and right sides is narrowed, Since the vibrating membrane 42 is screwed in the state of being pulled up and down or left and right, the pulling tension is increased accordingly. Further, instead of changing the drilling position of the screw insertion hole 42a, for example, the screw insertion hole 42a itself may be formed as an elongated hole and the insertion position of the tightening screw 44 may be changed within the range of this elongated hole. The tension applied to the vibrating membrane 42 can be adjusted.

Further, in the third embodiment, the vibrating membrane 42 is fastened and fixed by the fastening screws 44, one on each side, but the flat speaker shown in FIGS. 6A, 6B and 6C is used. As in 51, each side of the vibrating membrane 52 may be fixed to the support frame 53 by using a plurality (here, two) of tightening screws 54. In the present embodiment, the washer 56 does not have four sides integrally formed in consideration of the ease of screw tightening, but is disassembled into an upper side portion, a lower side portion, a left side portion, and a right side portion, but the fret 55 has a rectangular frame. It is integrated into a shape.

In each of the above embodiments, the support frame 33,
The flat speaker 6 shown in FIGS. 7 (A), (B), and (C) was used as the ones having the four sides integrally formed as 43 and 53.
As shown in FIG. 1, the support frame 63 in which a total of four frame members, which are independent from each other in the vertical and horizontal directions, are interconnected via the adjusting screw 64, may be used. In the case of this embodiment, the support frame 6
The adjusting screw 64 that connects the frets 65 protruding from the frame 3 and the frame members constitutes a tension tension urging means. By rotating the adjusting screw 64 in the normal direction or in the reverse direction, the adjusting screw between the adjacent frame members is adjusted. The screwing length of 64 can be adjusted to adjust the connecting distance of each side. Specifically, for example, if the adjustment screw 64 on the upper right is operated to extend the connection distance, the frame member on the right side is separated from the frame member on the upper side.
The tension of the vibrating membrane 62 is increased in the right upper diagonal direction. On the contrary, if the connecting distance is reduced by operating the adjusting screw 64 on the upper right side, the frame member on the right side approaches the frame member on the upper side, and the vibrating film 62 moves in the upper right direction. Tension decreases. Similarly, the tension of the vibrating membrane 62 can be increased or decreased in the diagonally lower left direction by operating the adjusting screw 64 diagonally lower left. Furthermore, the adjusting screw 64 on the upper left side
The tension of the vibrating membrane 62 can be adjusted in the diagonally left upper direction by the operation of, and the tension of the vibrating membrane 62 can be adjusted in the diagonally right lower direction by the operation of the diagonally lower right adjustment screw 64. Thus, the tensile tension can be independently applied to the vibrating membrane 62 in the direction toward the four vertices, and the vertical component or the lateral component of each tension is vector-added to obtain the vibrating membrane 62. Is given the tension of.

Furthermore, FIGS. 8 (A), (B), and (C)
Like the flat speaker 71 shown in FIG. 2, the tension tension urging means is fixed to the fret 75, which is protruded from the inner edge of the support frame 73 and abuts the fixed film portion 72b of the vibrating membrane 72 to define the vibrating end. It may also be configured by a welding portion 72c which is formed by heating on the film portion 72b and shrinks and is welded to the support frame 73 when heated. As a material suitable for the vibrating membrane 72, PET or acetate film having heat shrinkability that shrinks by heating is preferable. In assembling the flat speaker 71, first, the fixed film portion 72b of the vibrating film 72 is attached to the support frame 73.
Then, the central portion of each side of the support frame 73 is linearly heated along the ridge of the fixed film portion 72b by a dedicated laminator (not shown). The portion heated by the laminator is thermally shrunk and welded to the support frame to shrink. That is, since the contracted welded portion 72c tensions the vibrating membrane portion 72a via the fixed membrane portion 72b, the vibrating membrane 72 is fixed to the support frame 73 and the tensile tension is urged at once by the heating work by the laminator. . In this case, since the thickness of the welded portion 72c is not so different from that of the fixed film portion 72b, the speaker as a whole can be made flat and thin. If the tensile tension decreases with time, the existing welded portion 72 is re-heated by the heating work.
By forming a new welded portion inside c, it is possible to easily restore or enhance the tensile tension.

In the flat speaker 71 shown in the sixth embodiment, the height of the frets 75 formed on the inner edge of the support frame 73 is set to be the same and uniform on all sides. Like the flat speaker 81 shown in FIG.
It is also possible to change to a fret 85 having an arc-shaped outline that is most raised in the central portion of each side of. By using the fret 85 having a shape protruding toward the central portion, the concentration of the tensile tension at the contact points of the adjacent fixed film portions 82b, that is, at the four corners of the vibration film portion 82a of the vibration film 82 is relieved. Therefore, the tensile tension is made uniform over the entire vibrating film portion 82a, and the entire film can be vibrated favorably from the center of the back surface of the vibrating film portion 82a. The welded portion 82
Similar to the flat speaker 71, c is formed linearly along the ridgeline of the fixed film portion 82b.

In the flat speaker 71, 81, the upper and lower sides and the left and right sides of the heat-shrinkable vibrating membranes 72, 82 are welded to the support frames 73, 83 by using a laminator. ), The upper and lower sides and the left and right sides of the heat-shrinkable vibrating membrane 87 with four corners cut off are fixed to the support frame 88 by adhesion, and heat is applied to the entire vibrating membrane 87 after the adhesion and fixation. It is also possible to adopt a structure in which tensile tension is applied in the vertical direction and the horizontal direction. As shown in FIG. 10B, the vibrating membrane 87 used in the flat speaker 86 is a PET having a heat shrinkage characteristic in a specific uniaxial direction.
The film material 89 is cut and processed. That is,
In consideration of the shrinkage direction of the material due to heating shown by the arrow in the figure, the two orthogonal axes X, which are oblique to each other on two opposite sides of the film material 89 at an oblique angle of 0 to 90 degrees (excluding both ends), Y
The film material 89 is cut along the solid line so as to obtain the vibrating film 87 having upper and lower sides and left and right sides that are parallel to. As a result, in the vibrating membrane 87 obtained by cutting, the heat shrinkage direction is substantially diagonal. Therefore, after the upper and lower sides and the left and right sides of the vibrating membrane 87 are adhesively fixed to the support frame 88, the vibrating membrane 87 is used by using a flat panel heater, a warm air blower, an infrared heater or the like.
When heated, the vibrating membrane 87 tends to contract in the diagonal direction. As a result, as shown by the arrow in FIG.
As a biaxial component force of the tensile tension in the diagonal direction, the tensile tension is applied in the up-down direction and the left-right direction, and the vibrating membrane 87 is strained.

As described above, the tensile tension due to the heat shrinkability of the membrane material 89 is applied to the entire vibrating membrane 87, and the above-mentioned vibrating membrane 72 having the construction in which the tensile tension is generated at the welded portion,
82 is basically different from the tensile tension generation mode. That is, in the flat speaker 86, the thermal stress remaining in the vibrating membrane 87 which is heat-treated while the four sides are fixedly adhered to the supporting frame 88 and the frets 85 protruding from the supporting frame 88 constitute a tensile tension urging means. It is a thing. In this case, the vibrating membrane 87 in which the entire membrane is heat-shrinked is not necessarily adhered to the supporting frame 88.
Need not be fixed to the support frame 88, but can be fixed to the support frame 88 with a clip frame, a tightening screw, or the like. Further, regardless of the method of fixing to the support frame 8, the tension tension bias of the vibrating membrane 87 in the X and Y axis directions is performed by one heat treatment, so that a manufacturing method suitable for mass production can be easily applied. There is. Moreover, even if the vibrating membrane 87 is loosened to some extent at the time when the vibrating membrane 87 is fixed to the support frame 88, there is no problem as long as the vibrating membrane 87 is loosened to a tension state by the subsequent heat treatment. Further, since the heat shrinkage of the vibrating membrane 87 does not disappear even after the heat treatment, the flat speaker 86 in use is not used.
When the tensile tension of the vibrating film 87 decreases with the lapse of time, the tensile tension can be recovered by another heat treatment.

In the above embodiment, the flat speaker having a structure in which the vibrator is brought into contact with the center of the back surface of the vibrating film is taken as an example, but the flat speaker 91 shown in FIGS. 11 (A) to 11 (C) is used.
As described above, the vibrating film 72 may be formed of a transparent film, and a plurality of vibrators 94 may be disposed in contact with the vibrating film portion 92a in the vicinity of the periphery thereof. The planar speaker 91 is a square frame-shaped support frame 93 in which a fixed film portion 92b of a vibrating membrane 92 is tension-supported, and a pair of left and right holding bars 99 provided on the left and right sides of the upper and lower sides of the support frame 93. A pair of vibration exciters 94 are attached to each of them, so that the vibrating membrane portion 92a is vibrated and driven at two places on the left and right. In this flat speaker 91, most of the vibrating film portion 92a except the portion overlapping the pressing rod 99 transmits light, so that, for example, FIG.
As shown in FIG. 2, a direct-view CRT display 100
The audio output of the left and right channels can be distributed to the left and right exciters 94 for use. In this case, the vibrating membrane 92 may have a filter function of blocking harmful ultraviolet rays, and a very compact filter and speaker as a whole can be provided.

Further, the flat speaker 9 of the seventh embodiment described above.
In 1, the vibrating film 92 made of a transparent film may be replaced by a vibrating film made of an opaque film having a high light reflectance. The flat panel speaker 111 shown in FIG. 13 uses the vibrating film 2 made of an opaque film as a reflective screen for the front projection type liquid crystal projector 200, and the screen itself for displaying an image projected from the liquid crystal projector 200 receives an audio signal. Since it vibrates, it is possible to reproduce sound with excellent sound image localization, and it is possible to construct a video space full of realism. However, the amplitude of the vibrating membrane 112 is several μm.
However, it cannot be captured visually, and therefore, the reproduced image projected on the screen does not fluctuate and the viewer is visually adversely affected. The vibrator 114 shown in the present embodiment is fixed to the central portion of a pressing rod 119 provided between the center of the upper side and the center of the lower side of the support frame 113.

Further, although the flat speaker 111 shown in the seventh embodiment has an example in which the vibrating film 112 made of an opaque film is used, the vibrating film 112 is made of a semi-transparent film. In that case, the flat speaker can be used as a rear projection type screen that produces sound by combining with a liquid crystal projector that projects an image from the rear side of the screen instead of the front projection type.
However, since it is necessary to open the back surface of the screen on which the liquid crystal projector projects the image, the vibrator used for the flat speaker is not the center of the back surface of the vibrating membrane but the back surface as shown in the seventh embodiment. Should be located at the periphery.

In the above embodiment, the planar speakers 11, 31, 41, 51, 61, 7 using the rectangular diaphragms 32, 42, 52, 62, 72, 82, 92, 112 are used.
1, 81, 91, and 111 are taken as an example, the vibrating membrane may have any polygonal shape, and a vibrating membrane having a triangular, pentagonal, or hexagonal or more polygonal shape can be used. In that case, when using a polygonal vibrating membrane having even sides such as a quadrangle or a hexagon, a desired frequency characteristic can be realized by individually adjusting the tensile tension applied to the diagonal sides. When a polygon having an odd number of sides such as a triangle or a pentagon is used, a desired frequency characteristic can be realized by individually adjusting the tension in the direction connecting the apex and the opposite side.

In each of the above embodiments, the case where the vibrating membrane made of a single membrane material is used is taken as an example, but two membrane materials are united as in the vibrating membrane 310 shown in FIG. A vibrating membrane can also be used. The two film materials are a rectangular vertical film 311 in which fixed film portions 311b are arranged above and below the vibrating film portion 311a, and a rectangular horizontal film 312 in which fixed film portions 312b are arranged on the left and right sides of the vibrating film portion 312a. . Vertical membrane 3
11 and the horizontal membrane 312 are both vibrating membrane portions 311a and 312a in a state where the vibrating membrane portions 311a and 312a are overlapped with each other.
A few drops of a liquid 313 such as water or oil is inserted between them, and due to the surface tension of this liquid 311, the vibrating film part 311 is formed.
a and 312a are united. The vibrating membrane 310 shown in the present embodiment requires two membrane materials, the vertical membrane 311 and the horizontal membrane 312, but the vertical membrane 311 and the horizontal membrane 312 are integrated by the surface tension of the liquid 313 interposed in the middle. Therefore, for example, the vibrating film part 311a of the combined vertical film 311 is vertically contracted from the fixed film part 311b by being heated and shrunk along a ridge by a laminator or the like on a support frame (not shown). A tensile tension can be applied and a tensile tension can be applied to the vibrating membrane portion 312a of the lateral membrane 312 from the fixed membrane portion 312b in the left-right direction. Therefore, unlike a vibrating membrane consisting of a single rectangular film with four corners cut out, when tension is applied in all directions, the tension does not concentrate at the apex of the notch, and the vertical and horizontal directions It is possible to make each of the tensile tensions of each uniform, and to promise stable vibration over a long period of time.

Further, the vibrating membrane 310 exerts a pulling tension in the vertical direction on the vibrating membrane portions 311a and 312a that are combined with each other through the vertical membrane 311 and a pulling tension in the horizontal direction through the transverse membrane 312. A flat speaker (not shown) can be configured by exerting the force, and in that case, the vertical tension and the horizontal tension can be variably set without interfering with each other. In addition, such a flat speaker has a vibrating film portion 311.
Since a and 312a have the weight of two membrane materials, an extra driving force is required as compared with the case of driving a single membrane material, but the pulling tensions in the vertical and horizontal directions are equalized. Therefore, stable driving is possible for a long period of time. The vibrating film 310 is the same as the vibrating films 12, 32, 4
Instead of 2,52,62,72,82,92,112,
Any of the flat speakers 11, 31, 41, 51, 61,
It is also applicable to 71, 81, 91, 111.
Further, in the above description, the vibrating device uses the piston plate at the tip as the vibrating membranes 12, 32, 42, 52, 62, 72, 82 ,.
Although the description has been made assuming that the piston plates of 92, 112, 310 are brought into contact with each other to be assembled, the piston plate of the vibration exciter can be joined to the vibrating membrane by, for example, pressure contact or adhesion. However, even when adopting the method of connecting the vibration exciter to the vibrating membrane by such pressure contact and adhesion,
Since the vibrating membrane itself is pulled in all directions, a joining mode of temporary fixing is sufficient, and excessive strength is not required at the joining points.

[0040]

As described above, the vibrating membrane of the present invention according to claim 1 has a polygonal vibrating membrane portion which is vibrated by being vibrated from the outside, and each side of the vibrating membrane portion is independent of each other. And a fixed film part that is integrally formed by extending to the peripheral side and that supports and fixes the vibrating film part in a state in which tensile force is applied to the vibrating film part. By supporting the part in a tensioned state, the excitation energy applied to the vibrating film part can efficiently vibrate and drive the vibrating film part, and the function as a sounding body can be fully exerted with a small driving force. In the polygonal vibrating membrane part, since the distance from the excitation point to each side is variously different, the resonance frequency is widely dispersed,
Thereby, it is possible to reproduce sound in a wide band, and further, by adjusting the tensile tension exerted on the vibrating membrane portion, it is possible to freely variably adjust the reproduction frequency characteristic according to the intended use.

The vibrating membrane of the present invention according to claim 6 is
A rectangular vibrating membrane part formed by forming rectangular cutouts at four corners of a square film material and surrounded by a line connecting the cut apexes of the cutouts or a line passing therethrough, Since the fixed film part is formed by excluding the vibrating film part from the formed film material, the vibrating film part and the fixed film part are formed by forming rectangular cutouts at the four corners of the rectangular film material. And (3) can be easily manufactured at the same time, and vibrating membranes of various sizes can be uniformly formed in a large amount.

In the vibrating membrane of the present invention, the vibrating membrane portion and the fixed membrane portion are made of polyethylene terephthalate or metal-deposited polyethylene terephthalate, or polyethylene naphthalate or metal-deposited polyethylene naphthalate, or Since it is made of carbon fiber, it is possible to maintain stable vibration characteristics for a long period of time by using a synthetic resin material suitable for film processing or a synthetic fiber material that has high tensile strength and is used as a film material. On the other hand, by applying metal vapor deposition to increase the tensile rigidity, it is possible to constantly maintain stable vibration characteristics with little deterioration over time.

Further, in the flat speaker of the present invention according to claim 5, each side is supported by the support frame in a state in which a tensile tension is applied to the polygonal vibration film from the central portion toward the peripheral portion,
Since the vibrating membrane is vibrated and driven by the vibration exciter that is in contact with the back surface of the vibrating membrane, the polygonal vibrating membrane in which the distance from the driving point of the vibration exciter to the peripheral portion changes depending on the direction Unlike a circular vibrating membrane in which the distance from the driving point of the part to the peripheral part is the same in all directions, it has a sufficiently wide reproduction frequency band to have a large number of resonance frequencies,
Furthermore, when using a polygonal vibrating membrane having even sides such as a quadrangle and a hexagon, desired frequency characteristics can be realized by individually adjusting the tensile tension applied to the diagonal sides, while a triangular or When using a polygonal vibrating membrane with an odd number of sides such as a pentagon, it is possible to achieve the desired frequency characteristics by individually adjusting the tension in the direction that connects the vertex and the opposite side. Does not need to be fixed to the back surface of the diaphragm, it can be simply brought into contact, so the speaker assembly time is short, and the fixing point does not regulate the vibration of the diaphragm. Since it is supported by pulling in all directions, the damper inside the vibration exciter does not need strength, and the damper does not hinder the light movement of the movable part. Since there is no posture deviation when abutting, it is not necessary to secure room for tilting the axis in the movable part inside the exciter, which minimizes the magnetic gap in the exciter and maximizes the magnetic efficiency. As a result, the vibrating membrane under tension can be used as a light source while still being a sufficient vibration source, and a sufficient volume can be generated with a slight driving force. Headphone output attached to audio equipment or video equipment Since it can be directly driven by directly connecting to the terminal, it is suitable for a speaker for portable AV equipment that does not require a special power amplifier, and since the vibrating membrane is supported by the support frame in a tensioned state, it is basically Like a conventional flat panel speaker whose peripheral edge is a free end, the planar shape is lost due to the moisture absorption effect over the course of use, and piston vibration cannot be expected and the reproduced sound is refined. It is possible to maintain high-quality reproduction characteristics constantly without any loss, and the vibrator that drives the vibrating membrane is only in contact with the vibrating membrane at the driving point. If there are multiple vibrating membranes with different pictures or patterns or vibrating membranes on which pictures can be freely attached, the user selects one of these vibrating membranes and leaves the vibrator as it is. It is possible to replace only the vibrating membrane, and in consideration of use as a photo stand or upholstery, it is possible to provide an end-user-oriented usability while suppressing the replacement cost, which is an excellent effect.

Further, in the flat speaker of the present invention according to claim 7, the four sides of the rectangular vibrating membrane with the four corners cut out are individually applied to the upper and lower sides and the left and right sides in the separating direction. Since the vibrating membrane is vibrated and driven by the vibrator that is supported by a square frame-shaped support frame and is in contact with the back surface of the vibrating membrane, the square from the drive point of the vibrator to the peripheral edge changes depending on the azimuth. The characteristic feature of the shaped diaphragm is that it can obtain a sufficiently wide reproduction frequency band due to the existence of a large number of resonance frequencies. The desired frequency characteristics can be realized by applying the above, and since the four corners of the vibrating film are notched, the vertical tension tension and the horizontal tension tension do not interfere with each other, and Can be variably set, and the vibrator does not have to be fixed to the back surface of the vibrating membrane, but can be simply brought into contact with the vibrating membrane. Since the vibration is not regulated and the vibrating membrane is pulled and supported in all directions, the damper inside the vibrator does not need strength, and the damper does not hinder the light movement of the movable part. Since there is no posture deviation when the shaker is brought into contact with the vibrating membrane, it is not necessary to secure room for tilting the axis of the movable part inside the shaker, which minimizes the magnetic gap inside the shaker. It is possible to increase the magnetic efficiency to the utmost, and thus, the vibrating membrane urged by tensile tension can be used as a sufficient vibration source while being lightweight, and can generate a sufficient volume with a slight driving force. Since it can be directly driven by directly connecting it to the headphone output terminal attached to the video device, it is suitable for a speaker for a portable AV device that does not require a special power amplifier. For example, a plastic containing a CD (compact disc) By finishing the speaker to a shape similar to that of a case, full-scale sound reproduction at a destination is possible, and since the vibrating membrane is supported by the support frame in a tensioned state, the peripheral portion is basically a free end. Unlike conventional flat speakers, the flat shape is lost due to the effect of moisture absorption over the course of use, the piston vibration is not expected and the reproduced sound is not impaired, and high-quality reproduction characteristics are constantly maintained. In addition, since the vibrator that drives the vibrating membrane is only brought into contact with the vibrating membrane at the driving point, the printed pattern or design When a plurality of different vibrating membranes are prepared, the user can select one of these vibrating membranes, and it is also possible to replace only the vibrating membrane while leaving the vibrator.
In consideration of use as an upholstery product, there is an excellent effect that it is possible to provide an end-user-oriented usability while suppressing replacement costs.

Furthermore, in the flat speaker of the present invention according to claim 7, the tensile tension urging means is projectingly provided on an inner edge portion of the support frame and abuts on the fixed film portion to define a vibrating end. From a fret to be formed, an engagement groove formed in the support frame, and a clip member that engages with the engagement groove and locks a part of the fixed film portion of the vibrating film in the engagement groove. With this configuration, when the clip member is engaged in the engagement groove with a part of the fixed film portion of the vibrating film being locked, the part of the fixed film portion is not located between the clip member and the engagement groove. The fixed film portion, which is tightly sandwiched between and is locked by the frictional force acting on the close contact surface, supports the vibrating film portion with a tensile tension according to the engagement depth of the clip member, thereby the portion surrounded by the frets. It is possible to maintain the fixed membrane part of the machine in an appropriate tension state and achieve the desired vibration characteristics. The effect of such kill.

Further, the pulling tension urging means is projectingly provided on an inner edge portion of the support frame, and the frets for contacting the fixed film portion to define the vibrating end are connected to each side of the support frame. Since it is composed of an adjusting screw which is interposed in the portion and variably adjusts the connecting distance, the connecting distance between two adjacent sides of the four sides forming the support frame is variably adjusted by tightening the adjusting screw or loosening it vice versa. By adjusting the distances of the four connecting parts individually, the tension applied to the vibrating membrane can be adjusted freely, and the delicate tension adjustment according to the screw feed amount of the adjusting screw can be performed accurately. The effect such as possible is produced.

Further, the pulling tension urging means includes a fret, wherein the pulling tension urging means is projectingly provided on an inner edge portion of the support frame and abuts on the fixed film portion to define a vibrating end. Since the fixed film portion of the vibrating film is formed by heating, and is composed of a welding portion that shrinks and is welded to the support frame when heated, the fixed film portion of the vibrating film is applied to the support frame and heated from the outside. When the heating part is contracted and welded to the support frame, the welded part contracts and the vibrating film part is tensioned via the fixed film part, so that the vibrating film is fixed to the support frame and the tensile tension is applied. It can be achieved at one time by external heating work, and since the thickness of the welded part is not much different from the fixed film part,
The entire speaker can be made flat and thin, and if the tensile tension decreases over time, a new welded portion is formed inside the existing welded portion by the reheating work, and the pulling tension is reduced. There is an effect that the tension can be restored or increased easily.

The vibrating membrane according to claim 6 has a heat-shrinkability only in a specific uniaxial direction, and is a quadrangular film partitioned by four sides parallel to two orthogonal axes oblique to the specific uniaxial direction. Molded from a material, the tensile tension urging means,
When the vibrating film is projected on the inner edge of the supporting frame and heat-shrinks the vibrating film in a state where the fixed film part of the vibrating film is supported and fixed to the supporting frame, the vibrating film is closely contacted with the fixed film part. Since the vibrating membrane is configured to have a fret that tensions the vibrating membrane in the orthogonal biaxial directions and forms the vibrating end in a divided manner, the vibrating membrane can be pulled in the biaxial orthogonal directions by one heat treatment regardless of the fixing method to the supporting frame. Since tension can be applied, a manufacturing method suitable for mass production can be easily applied, and even if the vibrating membrane is slightly loose at the time of fixing the vibrating membrane to the support frame,
If the vibrating membrane is loosened to the tension state by the subsequent heat treatment, there will be no problem at all, and the heat contraction property of the vibrating membrane will not disappear even after the heat treatment, so that the tension of the vibrating membrane of the flat speaker in use is pulled. When the tension decreases with the lapse of time, it is possible to recover the tension by performing the heat treatment again.

Further, in the flat speaker of the present invention according to a twelfth aspect, the vibrating film is made of a transparent film or a semi-transparent film through which at least the vibrating film part transmits light, and the exciter has the vibrating film part. Since the vibrating membrane portion is vibrated and driven at a plurality of upper and lower portions or left and right portions, and most of the central portion of the vibrating membrane portion is used as a light transmitting region, for example, a direct-view type C
A transparent vibrating membrane placed in front of the RT display or liquid crystal display, etc. is used as a sounding body with a filter function to block harmful ultraviolet rays, and at the same time, it protects the eyes and enhances the hearing sense, or has a semi-transparent vibrating membrane on the back. By arranging in front of the projection type liquid crystal projector and displaying the image rear-projected from the liquid crystal projector on the vibrating membrane, it is possible to provide a screen that produces sound with good sound image localization.

Further, in the flat speaker of the present invention according to a thirteenth aspect, the vibrating film is made of an opaque film which does not transmit light at least in the vibrating film part, and the vibrator is provided near the center of the vibrating film part. Since it is installed, for example, it is used as a reflection screen for a liquid crystal projector, and an image projected from a front projection type liquid crystal projector is projected on a vibrating membrane, and the vibrating membrane is vibrated by a vibrating device, which is excellent in sound image localization. It is possible to reproduce sound, and it is possible to construct an image space full of audio sensation.

According to a fourteenth aspect of the present invention, in the vibrating membrane of the present invention, a rectangular vertical membrane in which fixed membrane portions are arranged above and below the vibrating membrane portion and a rectangular horizontal membrane in which fixed membrane portions are arranged on the left and right sides of the vibrating membrane portion. Since it is provided with a membrane and a liquid which is interposed between the vibrating membrane portions of the transverse membrane and the vibrating membrane portions of the vertical membrane in a state of being overlapped with each other, and which brings the vibrating membrane portions together by surface tension, Two membrane materials, a membrane and a horizontal membrane, are required, but since the vertical membrane and the horizontal membrane are integrated by the surface tension of the liquid interposed in the middle, the vertical membrane is interposed in the united vibrating membrane part. It is possible to exert a tensile tension in the up and down directions and a tensile tension in the left and right directions through the transverse membrane, so that it can be stretched in all directions like a vibrating membrane consisting of a square single membrane with four corners cut away. When the tension is applied, the tension is concentrated at the notch apex. Not a, each pulling tension between vertical transverse direction and uniform, respectively, an excellent effect such as can be promises long-term stable oscillation.

A flat speaker according to a fifteenth aspect of the present invention is a square frame-shaped support for supporting and fixing the vibrating membrane according to the fourteenth aspect and the fixed membrane portions of the longitudinal membrane and the transverse membrane of the vibrating membrane. With respect to the frame and the vibrating membrane supported by the supporting frame, a tension tension bias is applied to the vibrating membrane portion of the vertical membrane in the vertical direction and to the vibrating membrane portion of the horizontal membrane in the horizontal direction. And a vibration exciter supported by the support frame and abutting against the back surface of the vibrating membrane portion of the vibrating membrane to vibrate and drive the vibrating membrane portion. The characteristic of the quadrangular vibrating membrane part in which the distance to the position changes depending on the azimuth is that a sufficiently wide reproduction frequency band can be obtained due to the presence of a large number of resonant frequencies. Apply vertical tension through the membrane, Since tensile tension can be exerted in the left-right direction via the lateral membrane, the vertical tension tension and the horizontal tension tension can be freely variably set without interfering with each other, and the vibrating membrane section Since it has the weight of two materials, it requires more driving force than when driving a single film material, but since the tensile tensions in the vertical and horizontal directions are made uniform,
An effect such as stable driving over a long period of time can be obtained.

[Brief description of drawings]

1A and 1B are a perspective view and an exploded perspective view, respectively, showing a schematic configuration of a first embodiment of a flat panel speaker of the present invention.

2A, 2B, and 2C are a front view, a vertical sectional view, and a rear view of the flat speaker shown in FIG. 1, respectively.

FIG. 3 is an enlarged cross-sectional view of a main part of the flat panel speaker shown in FIG.

4 (A), (B), and (C) are an exploded perspective view, a front view, and an enlarged sectional view of a main part, respectively, showing a schematic configuration of a second embodiment of a flat speaker of the present invention.

5 (A), (B), and (C) are an exploded perspective view, a front view, and an enlarged sectional view of an essential part, respectively, showing a schematic configuration of a third embodiment of a flat speaker of the present invention.

6 (A), (B), and (C) are an exploded perspective view, a front view, and an enlarged cross-sectional view of a main part, respectively, showing a schematic configuration of a fourth embodiment of a flat speaker of the present invention.

7 (A), (B), and (C) are an exploded perspective view, a front view, and an enlarged cross-sectional view of a main part, respectively, showing a schematic configuration of a fifth embodiment of a flat speaker of the present invention.

8A, 8B, and 8C are an exploded perspective view, a front view, and an enlarged cross-sectional view of a main part, respectively, showing a schematic configuration of a flat speaker according to a sixth embodiment of the present invention.

9A, 9B, and 9C are a front view, a side view of a main part, and a bottom view of a main part, respectively, showing a modification of the flat speaker shown in FIG.

10A and 10B are a front view showing another modification of the flat speaker shown in FIG. 8 and an explanatory view of a vibrating film cutting method, respectively.

11 (A), (B), and (C) are an exploded perspective view, a front view, and a cross-sectional view, respectively, showing a schematic configuration of a seventh embodiment of a flat panel speaker of the present invention.

12 is a schematic perspective view showing an application example of the flat panel speaker shown in FIG.

13 is a schematic perspective view showing another application example of the modification of the flat panel speaker shown in FIG.

14A and 14B are respectively a front view and a side view showing another embodiment of the vibrating membrane of the present invention.

FIG. 15 is a vertical cross-sectional view showing an example of a conventional flat speaker.

[Explanation of symbols]

11, 31, 41, 51, 61, 71, 81, 86 Planar speaker 12, 32, 42, 52, 62, 72, 82, 87 Vibration film 12a, 72a, 82a Vibration film part 12b, 72b, 82b Fixed film part 13, 33, 43, 53, 63, 73, 83 Support frame 14, 74 Vibrator 15 Voice coil 15a Piston plate 16 Yoke 17 Annular magnet 18 Damper 19 Holding bar 20, 35, 45, 55, 65, 75, 85 Frets 22, 36 Engagement grooves 23 Clip rods 34 Clip frames 42a Screw insertion holes 44, 54 Tightening screws 72c, 82c Welded parts 91, 111 Flat speakers 92, 112, 310 Vibration films 92a, 311a, 312a Vibration film parts 92b, 311b , 312b Fixed film parts 93, 113 Support frames 99, 119 Presser bar 114 Vibrator 311 Vertical film 312 Lateral membrane 313 liquid

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI // H04R 1/00 310 H04R 1/00 310F C08L 67:02 C08L 67:02 (72) Inventor Tetsuji Musha Osaka City, Osaka Prefecture Central 1-4-2-4, Shiromi-ku, Nippon Electric Home Electronics Co., Ltd. (56) Reference JP-A-1-295598 (JP, A) JP-A-58-8000 (JP, A) JP-A-61-4400 ( JP, A) JP 54-153621 (JP, A) Actual development 48-58737 (JP, U) JP 41-8363 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04R 7/04 H04R 7/02 H04R 7/24 H04R 9/00 H04R 1/00 310 C08L 67:02

Claims (20)

(57) [Claims] 1. A polygonal vibrating film portion that is vibrated by being vibrated from the outside, and is integrally formed by extending each side of the vibrating film portion independently of each other and extending to the peripheral side. A vibrating membrane, comprising: a fixed membrane portion that is supported and fixed in a state in which tensile tension is applied. 2. The vibrating membrane according to claim 1, wherein the vibrating membrane portion and the fixed film portion are made of polyethylene terephthalate or metal-deposited polyethylene terephthalate. 3. The vibrating membrane according to claim 1, wherein the vibrating membrane portion and the fixed film portion are made of polyethylene naphthalate or metal-deposited polyethylene naphthalate. 4. The vibrating membrane according to claim 1, wherein the vibrating membrane portion and the fixed membrane portion are made of carbon fiber. 5. The vibrating film according to claim 1, a support frame for supporting and fixing the fixed film portion of the vibrating film, and the vibrating film of the vibrating film supported by the support frame. A tension tension urging means for urging tension tension from the central portion to the peripheral portion with respect to the vibrating film portion, and supported by the support frame,
A flat speaker comprising: a vibrator that abuts a back surface of the vibrating film portion of the vibrating film to vibrate and drive the vibrating film portion. 6. A rectangular vibration formed by forming rectangular cutouts at four corners of a square film material and surrounded by a line connecting the cut apexes of the cutouts or a line passing in the vicinity thereof. The vibrating membrane according to any one of claims 1 to 4, further comprising: a membrane portion and a fixed membrane portion formed of a region of the molded membrane material excluding the vibrating membrane portion. 7. The vibrating membrane according to claim 6, a square frame-shaped support frame for supporting and fixing the fixed membrane portion of the vibrating membrane, and the vibrating membrane portion of the vibrating membrane supported by the support frame. On the other hand, a tension tension urging means for individually urging tension tension in the separating direction on the upper and lower sides and on the right and left sides respectively, and the vibrating film supported by the supporting frame and abutting on the back surface of the vibrating film part of the vibrating film. A flat speaker comprising: a vibration exciter that vibrates and drives the unit. 8. The pulling tension urging means is provided on an inner edge portion of the support frame so as to project, and a fret that abuts on the fixed film portion to define a vibrating end and a member provided on the support frame. 8. The flat speaker according to claim 7, comprising a mating groove and a clip member that engages with the engaging groove and locks a part of the fixed film portion of the vibrating film in the engaging groove. . 9. The pulling tension urging means is provided on an inner edge of the support frame so as to project from the inner edge of the support frame. The flat speaker according to claim 7, wherein the flat speaker is an adjusting screw that is interposed in the portion and variably adjusts the coupling distance. 10. The tension tension urging means is provided at a fret protrudingly provided on an inner edge portion of the support frame and abutting against the fixed film portion to define a vibrating end, and a fixed film portion of the vibrating film. The flat speaker according to claim 7, wherein the flat speaker is formed by heating and contracts when heated to weld to the support frame. 11. The vibrating film according to claim 6, which has a heat shrinkability only in a specific uniaxial direction, and has a quadrangular shape partitioned by four sides parallel to two orthogonal orthogonal axes oblique to the specific uniaxial direction. The tensile tension urging means is formed from a film material, and the tensile tension urging means projects from the inner edge of the support frame, and heat-shrinks the vibration film with the fixed film portion of the vibration film supported and fixed to the support frame. 8. The flat speaker according to claim 7, further comprising a fret which, when being made to come into close contact with the fixed film portion, tensions the vibrating film in the orthogonal biaxial directions to partition and form a vibrating end. 12. The vibrating film comprises at least the vibrating film part made of a transparent film or a semi-transparent film that transmits light, and the vibrating device is arranged in the vicinity of the periphery of the vibrating film part. The flat speaker according to any one of claims 7 to 11. 13. The vibrating film, at least the vibrating film part is made of an opaque film that does not transmit light, and the vibrator is disposed near the center of the vibrating film part. 11. The flat panel speaker according to any one of 11 above. 14. A quadrangular vertical membrane in which fixed membrane portions are arranged above and below the vibrating membrane portion, a quadrangular transverse membrane in which fixed membrane portions are joined to the left and right of the vibrating membrane portion, and vibration of the transverse membrane and the vertical membrane. 5. A liquid, which is interposed between the vibrating membrane portions in a state where the membrane portions are superposed on each other, and which combines the vibrating membrane portions with each other by the surface tension. The vibrating membrane according to. 15. The vibrating membrane according to claim 14, a square frame-shaped support frame for supporting and fixing each fixed membrane portion of the longitudinal membrane and the transverse membrane of the vibrating membrane, and the vibration supported by the support frame. With respect to the membrane, the vibrating membrane portion of the vertical membrane is vertically supported, and the vibrating membrane portion of the horizontal membrane is supported by the support frame, and the tension tension urging means is configured to apply tensile tension in the horizontal direction. A flat speaker comprising: a vibrator that abuts a back surface of the vibrating membrane portion of the membrane to vibrate and drive the vibrating membrane portion. 16. The tension tension urging means is provided at an inner edge portion of the support frame so as to project, and a fret that abuts against the fixed film portion to define a vibrating end and a member provided in the support frame. The flat speaker according to claim 15, comprising a mating groove and a clip member that engages with the engaging groove and locks a part of the fixed film portion of the vibrating film in the engaging groove. . 17. The pulling tension urging means is provided at the inner edge of the support frame so as to project, and the frets for contacting the fixed film portion to define the vibrating end are connected to each side of the support frame. The flat speaker according to claim 15, wherein the flat speaker is an adjusting screw that is interposed in the portion and variably adjusts a coupling distance. 18. The tension tension urging means is provided on a fret protruding from an inner edge portion of the support frame and abutting against the fixed film portion to define a vibrating end, and a fixed film portion of the vibrating film. The flat speaker according to claim 15, wherein the flat speaker is formed by heating and shrinks when heated to be welded to the support frame. 19. The vibrating film comprises at least the vibrating film part made of a transparent film or a semi-transparent film that transmits light, and the vibrating device is arranged near a periphery of the vibrating film part. The flat speaker according to any one of claims 15 to 18. 20. The vibrating film, at least the vibrating film portion is made of an opaque film that does not transmit light, and the vibrator is disposed near the center of the vibrating film portion. 18. The flat panel speaker according to any one of 18 items.