JPWO2014119319A1 - Device having flexible substrate - Google Patents

Abstract

The speaker (10) is formed with a voice coil wiring (60) and functions as a flat plate acoustic transducer and a driving circuit section (58) for supplying an acoustic signal to the voice coil wiring (60). A flexible substrate (50) including a housing, a housing (20) for accommodating the flexible substrate (50), and magnet plates (31) and (32) disposed so as to sandwich the vibration circuit portion (59). The flexible substrate (50) further includes a slit (55) formed between the vibration circuit portion (59) and the drive circuit portion (58).

Description

  The present invention relates to an apparatus having a flexible substrate.

  Japanese Patent No. 3192372 discloses a permanent magnet plate, a vibration film disposed so as to face the permanent magnet plate, a buffer member interposed between the vibration film and the permanent magnet plate, and the vibration. A support member that regulates the relative position of the film to the permanent magnet plate, and the permanent magnet plate has a plurality of parallel stripes in which strip-like N poles and S poles appear alternately on almost the entire surface facing the vibration film. A pole magnetized pattern is formed, and a plurality of exhaust through-holes are arranged at the neutral zone position in the magnetized pattern, and the vibrating membrane is formed from a meander-shaped lead pattern on a thin and flexible resin film. The coil is a printed wiring structure in which a linear portion of the conductor pattern is provided at a position corresponding to the neutral zone of the permanent magnet plate, and is not fixed at the peripheral portion by the support member. Although the displacement in the inward direction is restricted, it is supported so as to be freely displaceable in the thickness direction, and the cushioning member is soft and air permeable and has a plurality of sheets of the same size as the vibrating membrane. There is described a thin electromagnetic transducer characterized in that it has a stacked structure and is disposed so as to have a gap between the sheet and the permanent magnet plate or the vibration membrane.

  There is a demand for a device having a simple configuration in which an acoustic conversion functional component such as a speaker or a microphone and an electronic circuit for driving the component are integrated.

  One embodiment of the present invention includes a flexible substrate including a vibration circuit unit that functions as a flat plate acoustic transducer, a housing that houses the flexible substrate, and a magnet plate disposed to face the vibration circuit unit. It is. The flexible substrate further includes a drive circuit unit that supplies an acoustic signal to the voice coil wiring, and the drive circuit unit and the voice coil wiring are connected by connection wiring formed on the flexible substrate. In this apparatus, a part of the flexible substrate is used as a flat acoustic transducer, typically a diaphragm for a flat speaker. At the same time, a drive circuit unit that outputs an acoustic signal to other parts of the common (same) flexible substrate is configured, and the voice coil wiring and the drive circuit unit that allow the common flexible substrate to function as a diaphragm are shared by a flexible Connection is made in the substrate by connection wiring formed on the substrate. In this flexible substrate, the drive circuit unit and the voice coil wiring can be manufactured in the same process, and it is not necessary to connect the drive circuit unit and the voice coil wiring in separate processes. For this reason, not only can the man-hours required for manufacturing the apparatus be greatly reduced, but also the wiring length for connecting the drive circuit and the voice coil can be shortened. Accordingly, it is possible to provide a device that can suppress noise, has low cost, is highly reliable, and has good acoustic performance.

  The flexible substrate preferably includes a slit formed between the vibration circuit unit and the drive circuit unit and a bridge unit formed to have a narrow width by the slit, and the connection wiring is disposed in the bridge unit. The vibration characteristics of the vibration circuit unit that functions as a flat plate acoustic transducer can be improved, and the acoustic characteristics can be improved.

  The vibration circuit unit and the drive circuit unit may be disposed on the front or back of the flexible substrate or in the stack, and may be provided on a common flexible substrate. It is desirable that the vibration circuit unit and the drive circuit unit are juxtaposed on a common flexible substrate. These circuit units can be connected with a relatively short connection circuit, and noise can be easily suppressed.

  One form of the vibration circuit section is a polygon such as a triangle or a quadrangle, and it is desirable that slits and bridge sections are arranged along one side of the polygon, and the other side of the polygon vibrates in a free state. It is easy to improve the vibration characteristics of the vibration circuit unit that functions as a flat plate acoustic transducer. Furthermore, the voice coil wiring desirably includes either a wiring pattern orthogonal to one side of a polygon provided with slits or a parallel wiring pattern. The wiring pattern is formed so that the vibration circuit part of the flexible board vibrates in the thickness direction of the board. Even if a force is generated in the direction along the surface of the board, the wiring pattern is orthogonal to the slit. Alternatively, if the wiring patterns are parallel, non-uniform distortion hardly occurs around the slit, and the acoustic characteristics can be improved. In order to suppress the generation of force in the direction along the surface, it is desirable that the wiring pattern extends along the magnetization boundary of the magnetized surface of the magnet plate that is magnetized with multiple poles. Therefore, it is desirable that the magnet plate includes a magnetized pattern perpendicular or parallel to one side where the polygonal slit is formed. A typical shape (outline) of the vibration circuit unit is a quadrangle.

  Another aspect of the present invention is a flexible circuit board including a vibration circuit unit that has a voice coil wiring and functions as a flat plate acoustic transducer, and that supplies a sound signal to the voice coil wiring. And the drive circuit unit and the voice coil wiring are connected by a connection wiring formed on the flexible substrate. The flexible substrate may have a low rigidity by providing a concave or convex bridge portion between the vibration circuit portion and the drive circuit portion, or adjusting the thickness of the bridge portion by etching or the like. The movement of the vibration circuit section can be made closer to free vibration and the sound quality can be improved. Further, the influence of vibration on the drive circuit unit can be suppressed.

The figure which shows the external appearance of a speaker. The figure which expands and shows the structure of a speaker. The figure which shows the structure of the front and back of a flexible substrate. Sectional drawing which shows arrangement | positioning of wiring.

  FIG. 1 shows the appearance of a flat plate (planar) speaker as an example of an apparatus having an electroacoustic conversion function according to the present invention. FIG. 2 is a development view showing a schematic configuration of the flat speaker 10. The speaker 10 includes a plate-shaped housing 20, plate-shaped magnet plates 31 and 32 disposed on the upper and lower sides (front and rear, or left and right) of the housing 20, and buffer plates (buffer members) 41 on the magnet plates 31 and 32. And a flexible substrate (flexible printed circuit board, flexible printed wiring board, membrane wiring board) 50 on which a vibration circuit section (vibrating film section) 59 is disposed so as to be sandwiched via 42 and 42. The vibration circuit portion 59 of the flexible substrate 50 functions as a flat plate type (plane type) acoustic transducer.

  The housing 20 is made of metal, plastic, or wood, and may be made of other materials such as ceramic and glass. The housing 20 includes an upper housing 21 and a lower housing 22, each having a plurality of openings 23. The shape of the opening 23 is not limited to a circle, and may be a polygon, a net, a slit, or the like. Further, the housing 20 may constitute the speaker 10 alone, or may be a part of a television, a personal computer, a smartphone, other electrical products, or furniture. Further, the housing 20 may be a part of the interior of the vehicle or the interior of the room, and the housing 20 may be a part of other movable property or real estate.

  The magnet plates 31 and 32 housed inside the housing 20 are permanent magnet plates having a common configuration, and the striped N pole 35n and S pole 35s are parallel stripes on the front and back magnetized surfaces 33 by magnetization. Appear alternately. Further, a plurality of through holes 34 are provided along a boundary (magnetization boundary) 36 of the belt-like N pole 35n and S pole 35s (hereinafter, sometimes referred to as a magnetized region 35 regardless of the pole). .

  The magnet plates 31 and 32 may be a sintered magnet plate, a non-sintered magnet plate, a flexible magnet plate, a solid-structure magnet plate, or any other known magnet plate. The material to which magnetism is added may be a ferrite magnet, a rare earth magnet, a neodymium-iron-boron magnet, or the like. The thickness and shape of the magnetic plate 31 (square, rectangular, circular, elliptical, etc.) and structure (whether it is a single permanent magnet plate or a structure in which a plurality of permanent magnet plates are bonded together) are arbitrary. Depending on the design problem, it can be appropriately selected according to the characteristics, cost, manufacturing necessity, use condition, and the like. Also, the magnitude of the magnetic pole (magnetic field) (magnetization magnitude), the pole pitch, etc. are arbitrary and can be selected based on factors such as the size of the housing 20 and the required volume.

  In the following description, the speaker 10 having a structure in which the vibration circuit portion 59 of the flexible substrate 50 is sandwiched between the two magnet plates 31 and 32 will be described as an example. ) May face (face to face) the magnet plate. Further, the flexible circuit board 50 may be provided with the vibration circuit unit 59 on both sides, or the vibration circuit unit 59 may be provided only on one side. Further, instead of sandwiching the flexible substrate 50 between the magnet plates 31 and 32, the flexible substrate 50 may be arranged on both sides of one magnet plate, or a configuration in which a plurality of magnet plates and vibration films are laminated may be employed. .

  The buffer members 41 and 42 disposed between the magnet plates 31 and 32 and the vibration circuit portion 59 of the flexible substrate 50 are soft and have air permeability that allows sound waves to pass freely. This is a sheet-like member having substantially the same size as that of the vibration circuit portion 59 that functions as an acoustic conversion region (acoustic conversion element). One example of the buffer members 41 and 42 is formed by stacking a plurality of thin sheet-like nonwoven fabrics. When the buffer members 41 and 42 are formed by stacking a plurality of sheet-like members, it is desirable to arrange them so that they can be individually vibrated (displaced) without being bonded. The buffer members 41 and 42 prevent the vibration circuit unit 59 from colliding with the magnet plates 31 and 32 during operation to generate abnormal noise (noise that is not normal vibration sound), and prevent the vibration circuit unit 59 itself from generating divided vibrations. This includes controlling the generation of sound other than sound waves that are faithful to the sound source, such as preventing chatter noise.

  The flexible substrate 50 is a flexible substrate made of a thin resin film. For example, a polyimide film (aromatic polyimide film), a polyethylene terephthalate film, or the like is employed. The thickness of the flexible substrate 50 is preferably about 10-50 μm. The flexible substrate 50 may be a laminate of a plurality of films. The flexible substrate of this example is a square (rectangular) as a whole, and 50 to 90% of the total area is a square vibration circuit part (vibration film part) 59. The vibration circuit unit 59 may be 50% or less of the whole. In the vibration circuit portion 59, a plurality of wiring patterns to be voice coil wiring (voice coil wiring) 60 are formed on both surfaces 51 and 52.

  A portion 58 of the flexible substrate 50 excluding the vibration circuit unit 59 is a mounting region (drive circuit unit), and a circuit for supplying an acoustic signal to the vibration circuit unit 59 and a processing unit 85 are mounted (mounted). A boundary 57 between the drive circuit portion 58 and the vibration circuit portion 59 is a connection portion, and a voice coil wiring (wiring pattern) 60 provided in the vibration circuit portion 59 is connected by a connection wiring 69. The drive circuit portion 58 and the vibration circuit portion 59 are not connected (soldered) individually to the lines from both at the connection portion 57, but the connection wiring 69 which is a printed pattern provided on the surface of the common flexible substrate 50. Are connected integrally. The connection portion 57 of the flexible substrate 50 has a low rigidity structure. That is, most of the connection part 57 of the flexible substrate 50 is a slit-like opening (slit) 55 extending linearly, and the part left by the slit 55 becomes the bridge part 54, and the processing unit is connected to the bridge part 54. A wiring 69 for connecting 85 and the voice coil wiring 60 is disposed. The bridge portion 54 may be flat or a flexible connection having a convex (concave) cross section.

  That is, the flexible substrate 50 is rectangular in its entirety, the vibration circuit portion 59 that is an acoustic element is disposed on one side in the long side direction (longitudinal direction), and the drive circuit that drives the vibration circuit portion 59 on the other side. The part 58 is arranged, and the boundary between the juxtaposed vibration circuit part 59 and the drive circuit part 58 becomes a connection part 57, and a slit 55 extending in the short side direction is formed in the connection part 57. Therefore, the vibration circuit portion 59 is generally square (rectangular or square), and one side of the square is connected to the drive circuit portion 58 via the connection portion 57 in which the slit 55 is formed, and the other three sides of the square are Although they are in contact with the buffer members 41 and 42, they are basically housed in the housing 20 in a state where they can freely vibrate.

  The vibration circuit portion 59 having a square outline (square) has high space efficiency when housed in the housing 20, or the square housing 20 is easy to install at various locations. Therefore, the flexible substrate 50 having the square vibration circuit portion 59 is easy to ensure the performance as an acoustic element, that is, the sound output if the speaker 10 of this example. The vibration circuit unit 59 may be another polygon, for example, a triangle or a pentagon. The vibration circuit unit 59 is arranged so as to include any end of the flexible substrate 50, and the vibration circuit unit 59 is arranged on one side thereof. Can be provided as the connection portion 57, and the flexible substrate 50 including the vibration circuit portion 59 that easily vibrates and has high acoustic performance can be provided. In addition, by arranging the slit 55 along one side that is the connection portion 57 of the polygonal vibration circuit portion 59, the flexible substrate 50 including the vibration circuit portion 59 with higher acoustic performance can be provided.

  FIGS. 3A and 3B show both surfaces (upper surface and lower surface, front surface and rear surface, front surface and back surface) 51 and 52 of the flexible substrate 50. For reference, the arrangement of the magnetized regions 35n and 35s of the magnetized surface 33 of the opposing magnet plates 31 and 32 is shown.

  A wiring pattern (voice coil wiring) 60 including three wirings 61 a, 61 b and 61 c is formed on the surface 51 of the vibration circuit portion 59 of the flexible substrate 50. On the back surface 52 of the vibration circuit portion 59, a wiring pattern 60 including three wirings 61d, 61e, and 61f and having the same or symmetrical arrangement as the wiring pattern on the front surface 51 is formed. Further, a processing unit 85 connected to the respective wirings 61a to 61c and 61d to 61f via connection wirings (relay wirings) 69 is mounted on the surface 51 of the driving circuit unit 58 of the flexible substrate 50. A communication circuit component 81 and a battery 82 are mounted on the back surface 52 of 58.

  Circuit elements mounted on the drive circuit unit 58 are not limited to these, and a capacitor, a resistor, a chip for other applications, and a wiring for connecting them may be mounted depending on the application. An example of the processing unit 85 is a digital speaker driving unit including a driving circuit function, and the processing unit 85 supplies a digital acoustic signal to each of the wirings 61 a to 61 f of the vibration circuit unit 59. Wirings provided on the common flexible substrate 50 on which the drive circuit unit 58 and the vibration circuit unit 59 are mounted can be formed simultaneously by photoetching the flexible copper-clad print film including the voice coil wirings 61a to 61f. .

  A typical example of the processing unit 85 is a digital speaker driving device described in Japanese Unexamined Patent Publication No. 2010-28785. This drive device is composed of a ΔΣ modulator, a post filter, s drive circuits, a ΔΣ modulator, and a power supply circuit that supplies power to the post filter and s drive elements. The driving circuit corresponds to s digital signal terminals. This driving device is suitable for a digital speaker device that outputs a plurality of digital signals by a ΔΣ modulator and a mismatch shaping filter circuit and directly converts analog sound by a plurality of speakers driven by the plurality of digital signals.

  Since the configuration of the wiring pattern 60 provided on the front surface 51 and the back surface 52 of the vibration circuit unit 59 is common, the wiring pattern 60 on the front surface 51 will be described below. A wiring pattern 60 including a plurality of independent wirings 61a to 61c to which different electric signals are applied is a first array pattern extending along the magnetization boundary 36 of the magnetized surface 33 of the magnet plate 31 that is magnetized with multiple poles. 65 and a second array pattern 66 disposed on the edge side of the vibration circuit portion 59 and extending in a direction perpendicular to the magnetization boundary 36. In the first arrangement pattern 65, a plurality of wirings 61a to 61c are arranged at symmetrical positions with the magnetization boundary 36 as the center. That is, since the first array pattern 65 includes three wirings 61a to 61c, the wiring 61b is disposed along the magnetization boundary 36, and the wirings 61a and 61c are disposed in parallel to the wiring 61b at equal intervals. ing.

  Adjacent first array patterns 65 are connected by a second array pattern 66, and the order of the wirings 61 a to 61 c is reversed by the second array pattern 66. Therefore, in the adjacent first arrangement pattern 65, the arrangement order of the wirings 61a to 61c is reversed.

  FIG. 4 schematically shows a state where the vibration circuit portion (vibration portion) 59 of the flexible substrate 50 is sandwiched between the upper and lower magnet plates 31 and 32 in the speaker 10. The buffer member is omitted. Magnetized regions 35 (35n and 35s) magnetized in stripes appear on the surfaces (magnetized surfaces) 33 of the magnet plates 31 and 32. The perpendicular magnetic field component (absolute value) of the magnetized region 35 is the largest in the vicinity of the centers of the magnetized regions 35n and 35s, and the boundary between the magnetized regions 35n (N pole) and 35s (S pole) (magnetized boundary). ) It is the smallest in the vicinity of 36. This is because the magnetization magnetic field component is defined in the vertical direction. Since there is no vertical component magnetic field in the vicinity of the boundary 36, this region is sometimes referred to as a neutral zone. On the other hand, the horizontal component (component parallel to the surface of the permanent magnet plate) of the magnetic field 37 formed by these magnetized regions 35 is the smallest in the vicinity of the centers of the respective magnetized regions 35n and 35s, and in the vicinity of the magnetized boundary 36. Is the largest. This is because the lines of magnetic force 37 pass in an arc from the adjacent magnetized region 35n (N pole) to the magnetized region 35s (S pole).

  When an electric current is passed through the wirings 61a to 61c, a force that moves the vibration circuit unit 59 according to the direction of the magnetic field 37 works according to Fleming's left-hand rule. The horizontal component of the magnetic field 37 is a component that contributes to vibrating the vibration circuit unit 59 in the thickness direction. By applying a signal (current) to the wirings 61a to 61c, the vibration circuit unit 59 is vibrated in the thickness direction and is acoustically generated. Can be converted to Therefore, the wirings 61 a to 61 c are arranged along the magnetization boundary 36 having the largest horizontal component by the first arrangement pattern 65. On the other hand, the first array pattern 65 includes a plurality of wirings 61a to 61c. Therefore, a plurality of wirings 61 a to 61 c are arranged with a certain width in a direction perpendicular to the magnetization boundary 36. For this reason, when a current flows through the wirings 61a and 61c on both sides, it acts not only on the horizontal component of the magnetic field 37 but also on the vertical component, and moves the vibration circuit portion 59 in the thickness direction (vertical direction in this figure). There is a possibility that a force for moving 59 in a direction parallel to the flexible substrate 50 (a direction along the surface, in the horizontal direction in the drawing) is exerted.

  However, in the first arrangement pattern 65 of this example, the wirings 61 a and 61 c on both sides are arranged at positions symmetrical with respect to the magnetization boundary 36. Therefore, when signals having the same phase are supplied to the wirings 61a and 61c on both sides, the force in the reverse direction in the direction parallel to the flexible substrate 50 (horizontal direction) in the wirings 61a and 61c on both sides due to the vertical component of the magnetic field 37. Occurs. For this reason, the force that moves the flexible substrate 50 generated by the wires 61a and 61c in the horizontal direction is canceled, and the flexible substrate 50 can be vibrated up and down in a stable state to generate sound.

  In the flexible substrate 50, different electrical signals can be independently supplied to the wirings 61a to 61c. Therefore, the same electrical signal is not always supplied to the wirings 61a and 61c on both sides. However, when the wirings 61a to 61c are used as a sound source, the signal strengths supplied to the wirings 61a to 61c are often substantially equal on a time average. Further, by providing the processing unit 85 with a function of selecting and connecting the wirings 61a to 61c randomly or cyclically in units of clocks, the signal strength supplied to the wirings 61a to 61c can be further averaged. Between the processing unit 85 and the connection wiring 69, a circuit or a chip including a function of selecting and connecting the wirings 61a to 61c randomly or cyclically in units of clocks may be arranged.

  Further, in the adjacent first array pattern 65, the order of the wirings 61a to 61c is reversed. In the adjacent first array pattern 65, the direction of the current flowing through each of the wirings 61a to 61c is reversed. Therefore, in the same wiring, for example, the wiring 61c, the direction of the vertical component of the magnetic field 37 is the same and the direction of the current is reversed. For this reason, the force for moving the vibration circuit unit 59 generated by the wirings 61 a and 61 c in the horizontal direction is canceled between the adjacent first arrangement patterns 65. Therefore, even when electrical signals having different phases or electrical signals having different polarities are supplied to the wirings 61a to 61c, the vibration circuit unit 59 is vibrated up and down in a stable state, and the electrical signals are acoustically transmitted. It can be converted into a signal and output. In addition, the flexible substrate 50 including the vibration circuit unit 59 can be prevented from moving in the horizontal direction.

  Furthermore, the first array pattern 65 is arranged in parallel to the long side of the rectangular vibration circuit unit 59 and can be arranged so that the lengths of the wirings 61a to 61c are equal. For this reason, the force in the horizontal direction generated by the wirings 61a and 61c can be canceled because they have the same magnitude and different directions. Further, the first array pattern 65 extends in a direction orthogonal to the connection portion 57 that is one side of the rectangular vibration circuit portion 59, and in this respect as well, the boundary of the magnetized region that is the neutral zone (the magnetization boundary) ) The lengths of the wiring 61a and the wiring 61c arranged on both sides of 36 can be made equal. At the same time, the horizontal force generated in the region close to the connecting portion 57 can be canceled, so that the horizontal force applied to the connecting portion 57 can be suppressed. Therefore, the force in the direction along the surface generated around the slit 55 and the bridge portion 54 can be suppressed. Therefore, the vibration circuit unit 59 can be vibrated in the natural vibration mode in the vertical direction with respect to the fixed drive circuit unit 58 by the force generated by the wiring pattern 60 that is the voice coil wiring. Therefore, the flexible substrate 50 and the speaker 10 having excellent acoustic characteristics can be provided.

  Similarly to the above, when the first array pattern 65 is arranged in parallel to the short side direction of the square vibration circuit unit 59, the plane direction by the wiring 61a and the wiring 61c arranged on both sides of the magnetization boundary 36 is the same as above. It is easy to cancel this force (horizontal force). Further, since the lengths of the wiring 61a and the wiring 61c in the vicinity of the connection portion 57 can be made uniform, the horizontal force applied to the connection portion 57 can be suppressed. Therefore, also in the magnet plates 31 and 32, it is desirable that the magnetization boundary 36 is arranged in parallel with the long side or the short side direction of the rectangular vibration circuit portion 59. Further, it is desirable that the magnetized boundary 36 be disposed in a direction orthogonal to or parallel to the connection portion 57 that is one side of the rectangular vibration circuit portion 59. In other polygonal vibration circuit portions 59, in order to suppress the horizontal force applied to the connection portion 57, the wiring pattern 60 is in a direction orthogonal to or parallel to one side of the polygon that is the connection portion 57. It is desirable to extend in the direction. Similarly, it is desirable that the magnetization boundary 36 extends in a direction orthogonal to or parallel to one side of the polygon which is the connecting portion 57.

  The acoustic signal output by the vibration circuit unit 59 of the flexible substrate 50 is output to the outside through the through holes (through portions) 34 provided in the magnet plates 31 and 32. Further, the movement of the vibration circuit portion 59 and the buffer members 41 and 42 in the horizontal direction (direction parallel to the surface) can be restricted by providing the housing 20 with an appropriate stopper structure. For example, the movement of the flexible substrate 50 including the vibration circuit portion 59 on the side wall of the housing 20 can be restricted, or the movement of the flexible substrate 50 can be restricted by making the corner shape of the housing 20 oblique. Further, the horizontal movement of the flexible substrate 50 can be restricted by a member such as a pin.

  Further, the vibration circuit portion 59 of the flexible substrate 50 is housed in the housing 20 in such a manner that the three edges (peripheral ends) can freely vibrate, and one edge is connected to the drive circuit portion 58 via the connection portion 57. It is integrated. The connection portion 57 is a slit-shaped opening 55 except for the bridge portion 54 where the connection wiring 69 is disposed, and the bridge portion 54 is processed into a convex or concave flexible and low-rigid shape. May be. By making the rigidity of the connecting portion 57 very low, the entire peripheral edge (edge) of the vibration circuit portion 59 including the connection portion 57 can be freely vibrated, and the vibration circuit portion 59 vibrates in the free end state. Can be made. Therefore, vibration according to the electrical signal supplied to the wirings 61a to 61f can be excited in the vibration circuit unit 59, and high-quality sound can be output.

  In the flexible substrate 50, the drive circuit unit 58 and the vibration circuit unit 59 are integrated with each other through the connection unit 57. Therefore, the processing unit 85 mounted on the drive circuit unit 58 and the wiring pattern (voice coil wiring) 60 of the vibration circuit unit 59 can be connected by the printed pattern (connection wiring) 69 formed on the flexible substrate 50. For this reason, the acoustic signal output from the drive circuit of the processing unit 85 can be supplied to the voice coil wiring pattern 60 in a short pattern, and the influence of ambient noise and the like can be suppressed. In addition, the wiring mounted on the flexible substrate 50 including the drive circuit unit 58, the vibration circuit unit 59, and the connection circuit 69 is manufactured in a lump. For this reason, the manufacturing cost of the flexible substrate 50 including the drive circuit unit 58 and the vibration circuit unit 59 and the speaker 10 on which the flexible substrate 50 is mounted can be reduced.

  Since the connection wiring 69 can be formed by wiring printed on the flexible substrate 50, even when different acoustic signals are supplied to the plurality of wirings 61a to 61f included in the wiring pattern 60, a large number of connection wirings 69 are compared. It can be concentrated on the narrow bridge portion 54. Therefore, even if the amount of the acoustic signal increases, an increase in the area of the bridge portion 54 can be suppressed, and the connection portion 57 can be maintained with low rigidity, so that the vibration circuit portion 59 can be vibrated in a free state.

  For example, when the processing unit 85 has a drive circuit function or a digital signal processing function with a processing capability of about 100 MHz, a 24-bit digital acoustic signal is converted into a 6-circuit × 4-bit (16 divisions in the time direction) playback signal. It can be converted and supplied directly to each of the wirings 61a to 61f. The vibration circuit unit 59 of the flexible substrate 50 vibrates up and down by digital signals (reproduction signals) supplied independently to the wirings 61a to 61f, and a sound in which vibrations by the reproduction signals are synthesized is output.

  As described above, in the speaker 10 described above, a part of the flexible substrate 50 is used as the vibration circuit unit 59 to output sound. Therefore, in the above description, an apparatus that mainly performs the function as a speaker has been described as an example. However, in an information processing apparatus such as an information terminal and a portable terminal, an appliance such as a household appliance, an industrial machine, a vehicle, and the like, It is not necessary to mount the speaker unit on the flexible substrate 50 or to secure a space for storing the speaker unit in the housing in addition to the flexible substrate 50, and to easily store the flexible substrate 50 in the housing. A device having a function as a speaker can be provided with a simple configuration.

  The vibration circuit unit 59 may be made of a material and thickness suitable for sound output, and the drive circuit unit 58 may have a multilayer structure suitable for mounting circuit components and circuit formation.

  In the above description, the speaker 10 including the flexible substrate 50 including the vibration circuit unit 59 in which three wirings (three circuits) are formed on each of the front and back sides is described as an example. However, the wiring provided in the vibration circuit unit 59 is described. This number is not limited to this, it may be two wirings, may be four wirings or more, and wiring may be provided only on one of the surfaces. For example, when the wiring pattern 60 is two wirings, the two wirings are arranged at symmetrical positions around the magnetization boundary 36. In the above description, the wiring pattern 60 is folded back in the longitudinal direction (vertical direction) of the rectangular vibration circuit portion 59, but may be folded back in the width direction (lateral direction). The wiring pattern 60 for the voice coil is not limited to the above, and may be any wiring pattern that functions as a voice coil that vibrates the vibration circuit unit 59.

  Furthermore, the shape of the vibration circuit unit 59 is not limited to a rectangle, and may be a square or other shapes. In addition, the vibration circuit unit 59 may be provided at one end of the flexible substrate 50, may be provided at a plurality of ends, or may be provided in the flexible substrate 50, for example, at the center. .

  Further, the number of wiring patterns 60 that are meandering or zigzag bent (turned) is not limited to three. When the area of the vibration circuit unit 59 cannot be secured sufficiently, the wiring pattern 60 may be straight. The wiring pattern 60 preferably includes an even number of first array patterns 65, and in this case, the turn portion (second wiring pattern 66) of the wiring pattern 60 is preferably odd.

  Further, although the positions of the through holes (vent holes) 34 provided in the magnet plates 31 and 32 are arbitrary, it is desirable to arrange them along the magnetization boundary 36 where the displacement of the vibration circuit portion 59 increases. Further, the arrangement of the through holes 34 may be a staggered pattern or a lattice pattern, and may be circular, oval, or polygonal.

  Further, in the above description, the speaker in which the vibration circuit unit 59 outputs sound is described as an example. However, the device including the flexible substrate 50 has a function as a microphone in which the vibration circuit unit 59 converts sound into an electric signal. It may be a device. In an apparatus having a function as a microphone, a microphone that can flexibly set sound collection characteristics or output a digital signal can be provided.

Claims (9)

A flexible circuit board including a vibration circuit unit in which a voice coil wiring is formed and functions as a flat plate type acoustic transducer, further comprising a drive circuit unit for supplying an acoustic signal to the voice coil wiring, and the drive circuit unit and the A flexible substrate in which a voice coil wiring is connected by a connection wiring formed on the flexible substrate;
A housing for storing the flexible substrate;
And a magnet plate disposed so as to face the vibration circuit section. In claim 1,
The flexible substrate includes a slit formed between the vibration circuit unit and the drive circuit unit, and a bridge unit formed with a narrow width by the slit, and the connection wiring is disposed in the bridge unit. The equipment. In claim 2,
The apparatus in which the vibration circuit unit and the drive circuit unit are juxtaposed on the flexible substrate. In claim 2 or 3,
The vibration circuit section is a polygon, the slit and the bridge section are arranged along one side of the polygon, and the other side of the polygon vibrates in a free state. In claim 4,
The said voice coil wiring is an apparatus containing either the wiring pattern orthogonal to the said one side of the said polygon, or a parallel wiring pattern. In claim 5,
The wiring pattern extends along the magnetization boundary of the magnetized surface of the magnet plate that is multipolar magnetized,
The apparatus, wherein the magnet plate includes a magnetization pattern perpendicular or parallel to the one side of the polygon. In any of claims 4 to 6,
The vibration circuit unit is a square. In any of claims 1 to 4,
The voice coil wiring includes a wiring pattern extending along a magnetization boundary of a multipolar magnetized magnetized surface of the magnet plate. A flexible circuit board including a vibration circuit portion in which a voice coil wiring is formed and functions as a flat plate acoustic transducer,
A flexible board further comprising a drive circuit section for supplying an acoustic signal to the voice coil wiring, wherein the drive circuit section and the voice coil wiring are connected by a connection wiring formed on the flexible board.

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