JP5213802B2 - Omnidirectional speaker - Google Patents

Description

  A point sound source, which is an ideal omnidirectional speaker, is approximated by a small spherical sound source, and the spherical sound source itself is approximated by a polyhedral sound source having a polygonal unit surface. The present invention relates to a small omnidirectional speaker capable of selecting a dodecahedron having a regular pentagon as a unit surface as a polyhedron from the viewpoint of practicality, and capable of driving all of the twelve surface diaphragms.

  For a speaker or speaker unit aiming at an approximation of an ideal point sound source, omnidirectionality and small size are indispensable requirements. In particular, one of the inventors previously proposed in Japanese Patent Application No. 2009-088946. Since the “full-surface drive speaker” is small and thin, it provides a speaker unit that can be arranged in high density with a large number on the surface of the diaphragm, and can be applied to a polyhedron to realize a small omnidirectional speaker. Useful. On the other hand, even if we consider increasing the number of faces extremely as a polyhedron approximating a spherical sound source, or theoretically approximating a sphere, there are technical and cost problems in terms of actual manufacturing. Many are not suitable for practical use. On the contrary, even if a triangle is selected as the smallest unit surface, for example, when the above-described high-density array type speaker unit is adopted, the number of usable units is limited and the filling degree is lowered, which is not suitable. In view of these various points, it is advantageous to adopt a dodecahedron having a regular pentagonal unit surface, which is widely used in the past.

  The conventional omnidirectional speaker that approximates a spherical sound source with a dodecahedron can be broadly divided into the following three types. (1) is a pentagonal unit surface regarded as a baffle plate, and one speaker unit is attached to it. (2) A film is attached to the pentagonal unit surface as a diaphragm, and a voice coil is formed from the inner surface. (3) is a device in which an elastic diaphragm with an edge is attached to a unit surface instead of a film, and a voice coil and a circular magnetic circuit are driven from the inner surface.

  These conventional speakers have the following problems. In the case of (1), the outer circumference of the speaker unit is an inscribed circle of a unit surface pentagon or a circle having a smaller diameter, and the remaining portion of the pentagon outside this circle remains as an undriven region, The directivity characteristics of the speaker unit on each unit surface will be reflected in the overall characteristics, and therefore both miniaturization and non-directivity cannot be realized.

  In the case of (2) and (3), the total height of the magnetic circuit and the vibration system is limited due to the space restriction inside the unit surface, so that a large-diameter voice coil cannot be used. Therefore, the driving of the diaphragm is limited to the central region, and the region that enables piston vibration is narrowed. In addition, the vibration modes in the cases (2) and (3) are likely to generate divided vibrations. In that case, even if the outer shape of the speaker is omnidirectional, it has directivity and the quality as a sound source approximating a spherical sound source. Will fall.

  After all, in any of these cases (1) to (3), a speaker that is small enough to be a non-directional spherical sound source and has a sufficient piston vibration region has not been realized. Furthermore, in any case, it is necessary to individually assemble the twelve pentagonal unit elements and assemble them into a dodecahedron and connect the wires inside them, which is complicated and expensive. Become.

Japanese Patent Laid-Open No. 2006-311349

  As a problem to be solved, the present invention eliminates divided vibration by arranging a plurality of small and thin speaker units on each of the diaphragms of the unit surface and driving the entire surface, thereby enabling piston vibration. It is an object of the present invention to provide a small omnidirectional speaker that approximates a spherical sound source with a dodecahedron with pentagonal unit surfaces.

The omnidirectional speaker according to claim 1 of the present invention is a dodecahedron having a regular pentagonal unit surface, and each unit surface includes a plurality of flat magnetic circuits each forming an annular magnetic gap, and a unit surface. A frame having a regular pentagonal outer shape and holding a plurality of magnetic circuits in the plane thereof, and a plurality of circular voice coils formed corresponding to each of the magnetic gaps and sequentially connected to each other by connection lines. A diaphragm having a regular pentagonal outer shape on each unit surface and carrying a plurality of voice coils facing each of the magnetic gaps, and connecting the voice coil of each unit surface to the voice coil of the adjacent unit surface The voice coils of all twelve sides are connected in series by connecting to the starting point of the above through a bridge line.
According to a second aspect of the present invention, in the omnidirectional speaker according to the first aspect, the magnetic gap of the magnetic circuit and the voice coil are respectively a center of a regular pentagonal unit surface and a center of a line connecting each vertex and the center. It is characterized by comprising 6 pieces arranged concentrically.
According to a third aspect of the present invention, in the omnidirectional speaker according to the first aspect, each unit surface of the dodecahedron is integrally formed with a diaphragm carrying a voice coil on a frame holding a magnetic circuit. To do.
According to a fourth aspect of the present invention, in the omnidirectional speaker according to the first aspect, the dodecahedron is configured by a unit surface including a frame that holds a magnetic circuit, and is covered with a diaphragm that carries a voice coil. It is characterized by.
According to a fifth aspect of the present invention, there is provided the omnidirectional speaker according to the second aspect, wherein the diaphragm carrying at least the voice coil is connected to the adjacent unit surfaces only on one side in the unfolded state of all unit surfaces. The first end of one of the pair of signal lines divided into two in the circumferential direction of the first voice coil of the first unit surface, which is connected to the other unit surfaces by two sides. Then, one of the second to sixth voice coils divided in half is sequentially connected to one of the pair of connection lines, and one of the sixth voice coils is divided into the first and second ends. Connected to one of the ends of the seventh voice coil of the second unit surface via one of a pair of bridging lines straddling the connecting edge between the unit surfaces of the second unit surface. The seventh voice coil of the 12th unit surface from the seventh voice coil Connect one end of a pair of connection lines to one start end of the half of the cable, and connect one end of the 71st voice coil to one end of the C-shaped 72nd voice coil for connection. The other end of the 72nd voice coil is connected to the other half of the 71st voice coil, and thereafter the other half of the 71st to 1st voice coils are connected to a pair of connection lines. The other end of the first voice coil is connected to the other end of the pair of signal lines, and the other end of the first voice coil is connected to the other of the pair of signal lines. And

  A plurality of, preferably six, small and thin speaker units can be arranged at high density with respect to the diaphragms on each unit surface of the dodecahedron regular pentagon. The divided vibration in the band can be easily eliminated. As a result, the twelve-side diaphragm can perform the piston vibration in a wide band, and a high-quality and wide band omnidirectional speaker that approximates a spherical sound source can be realized.

  By using a thin speaker unit, the depth dimension of each unit surface can be reduced to realize a dodecahedron speaker that is remarkably miniaturized as a whole, and at the same time, a compact dodecahedron for ultra-high frequencies is realized. obtain.

  If a voice coil is formed as a flexible coil by printed wiring with a one-stroke pattern on a diaphragm that forms twelve continuous unit surfaces, wiring connection work inside the dodecahedron on the unit surface becomes unnecessary. When the diaphragm is attached on the magnetic circuit-equipped frame forming the dihedron, or when the diaphragm and the magnetic circuit are formed as an integral unit, the dodecahedron is assembled to complete the connection work.

FIG. 1 is a perspective view of an omnidirectional speaker corrected to a dodecahedron whose unit surface is a regular pentagon according to an embodiment of the present invention. 2A is a plan view of the unit surface of the dodecahedron in the embodiment of FIG. 1 on the inner side with the magnetic circuit, and FIG. 2B is a side view thereof. FIG. 3 is a developed view adopted for the dodecahedron in the embodiment of FIG. 1. Six voice coils that are originally hidden by the diaphragm and arranged in each regular pentagonal unit surface are shown in FIG. It is represented by a solid line to clearly indicate. FIG. 4 shows the principle of construction of a small and thin speaker unit used in the present invention. (A) is a magnetic gap connected in plural, (B) is a voice coil connected correspondingly, ( C) shows the combined state of the magnetic gap and the voice coil. FIG. 5 is an enlarged cross-sectional view showing the speaker unit constituting the unit surface of the dodecahedron in the embodiment of FIG.

  In the present invention, how to use the small and thin speaker unit of the above-mentioned previous invention “full-surface driving speaker” with a dodecahedron whose regular pentagon is a unit surface as shown in FIGS. However, prior to elucidating this in the embodiments of the present invention, an outline of the configuration of the full-surface driving speaker unit will be described with reference to FIG.

  In FIG. 4, (A) is a plurality of circular magnetic gaps MG connected in series. The outer side of the double circle represents a flat hole of a flat magnet or yoke, and the inner concentric circle represents a flat pole piece or magnet. (B) is a plurality of circular voice coils VC made of, for example, copper wire corresponding to the magnetic gap MG. All the coils are divided into upper and lower halves, except that the leftmost voice coil is C-shaped, and adjacent to each other. The upper half of the coil is connected to the upper half of the coil, and the lower half of the coil is connected from the right end to the front of the left end via a pair of parallel copper wires. Connect to both ends of the coil. That is, after sequentially tracing one of the upper and lower halves from one of the right end connection lines of the right end coil and making a U-turn with the left end C-shaped coil, the other of the upper and lower halves are sequentially followed to reach the other of the right end connection lines. Until then, all voice coils are connected in series by a so-called one-stroke pattern. The rightmost connection line is used as a signal input / output line. (C) shows a state in which the magnetic gap MG row and the voice coil VC row face each other. Actually, the voice coil VC is printed on a diaphragm made of, for example, a PI film, placed on the magnetic gap MG with a non-woven fabric interposed therebetween, and the periphery of the diaphragm is bonded to a frame to form a speaker unit.

  With the above-described configuration, the effective line length of the voice coil per area of the full drive speaker unit used in the present invention is greatly increased, and the area and shape of the diaphragm can be changed by combining a plurality of small and thin magnetic circuits and voice coils. The degree of freedom is increased, and the overall thickness is sufficiently suppressed.

  As described above, in the embodiment according to the present invention, a dodecahedron whose unit surface is a regular pentagon that can maintain a high degree of filling of the speaker unit is adopted as an approximation of a spherical sound source, and FIG. 1 shows a perspective view thereof. Each of the regular pentagonal unit surfaces 10 whose surface is the diaphragm 1 carries a total of six circular voice coils VC, one on the center and five on the line connecting the center and each vertex of the pentagon. On the inner surface side of the unit surface 10, as shown in FIG. 2A, six annular magnetic gaps MG formed by the magnetic circuits 5 and 6 face each other in a concentric relationship with the voice coil VC. Details of the configuration of the speaker unit forming the unit surface 10 will be described later with reference to FIG.

  The dodecahedron is formed by a unit surface in a developed view shown in FIG. There are several types of dodecahedron developments with respect to the pentagonal arrangement, but the S-shaped development is the closest to the straight line, that is, the pentagons at both ends are only one side, and the other pentagons are The development of FIG. 3 joined to adjacent pentagons on two sides is convenient to adopt when it is intended to connect a total of 72 voice coils one after another in series with the one-stroke pattern described for FIG. It is.

  The voice coils VC-1 to VC-72 are connected as follows. One SL-1 of the pair of signal lines is connected to one start end of the first voice coil VC-1 divided into two in the circumferential direction on the diaphragm 1-1 of the first unit surface 10, and from the second One half of each of the sixth voice coils VC-6 is sequentially connected to one of the pair of connection lines CL, and one end of the sixth voice coil VC-6 is divided into the first and second ends. The seventh voice coil VC-7 on the second diaphragm 1-2 is connected to one of the pair of bridge lines BL that straddles the joint between the diaphragms 1-1 and 1-2 on the unit surface. Connected to one of the start ends divided in half, the same connection was repeated, and the seventh voice coil VC-7 of the second diaphragm 1-2 to the 71st voice of the last twelfth diaphragm 1-12 One of the pair of connection lines is sequentially connected to one of the two ends of the coil VC-71, and the 71st voice coil VC-71 is connected. One end of the bisection is connected to one end of the last 72nd voice coil VC-72 which is C-shaped without being divided into two, and the connection is turned back to make the 72nd C-shaped voice coil VC-72. Is connected to the other half of the 71st voice coil VC-71, and then the other half of the 71st to 1st voice coils VC-71 to VC-1 The other end of the first voice coil VC-1 is connected to the other end of the pair of signal lines SL by connecting the other end of the pair of connection lines CL and the other end of the pair of bridge lines BL. Thus, all the voice coils VC-1 to VC-72 of the twelve-side diaphragms 1-1 to 1-12 are connected in series as a one-turn coil. The developed view of FIG. 3 shows a twelve-plane diaphragm in which all 72 voice coils included in all 12 unit surfaces 10 are connected in series.

  The twelve-side voice coils VC-1 to VC-72 are printed and wired on the surface of the diaphragm made of, for example, a PI film with the pattern shown in the developed view of FIG. 1-1 to 1-12 are formed and combined with a flat magnetic circuit MC having the structure of each unit surface 10 shown in the exploded enlarged sectional view of FIG. 5, and six circular voice coils VC are formed on each unit surface 10. Six annular magnetic gaps MG face each other concentrically as described with reference to FIG.

  The flat magnetic circuit MC may be either an internal magnetic type or an external magnetic type. Six disk-shaped magnetic cores or center poles arranged at the center and the center of each regular pentagonal unit surface 10 and the middle point of each apex angle. 6 and a yoke plate or magnet plate 6 having six round holes for concentrically accommodating each of these, six annular magnetic gaps MG are formed. In FIG. 5, the six voice coils VC and the six magnetic gaps MG are all shown in a straight line. Desirably, for example, the nonwoven fabric 4 is brought into contact with the opening side of the magnetic gap MG, the frame 3 is placed on each edge of the pentagon, and the diaphragm 1 carrying the voice coil VC is pasted on the upper surface thereof. 10 is formed. The side surfaces of each side of the unit surface 10 are chamfered at an angle of 116.6 degrees with respect to the extended war with the diaphragm 1 side as the surface, facilitating the creation of a dodecahedron. The length of one side of the pentagonal unit surface 10 is about 20 mm, the diameter of the magnetic gap is 8.8 to 6.5 mm, the height of the magnetic circuit is about 2 mm, and the total height is about 2.5 mm by adding the amplitude of the diaphragm. However, it is possible to further reduce the size. If the diameter of the magnetic gap is further reduced, the number of speaker units for each unit surface, that is, the number of driving points can be increased.

  In addition, after the dodecahedron is formed by integrating only the magnetic circuit MC and the frame 3 as the unit surface 10, a vibration plate in the state of development in FIG. 3 may be attached to the surface. Further, the development pattern of the dodecahedron is not limited to that shown in FIG. 3, and other similar or approximate patterns may be adopted. In short, any pattern may be used as long as all twelve sides of the voice coil are connected in series with a single stroke via a bridging line across the connecting side between adjacent unit planes and can be easily assembled into a dodecahedron.

10 Unit surface VC Voice coil VC-1 to VC-72 First voice coil to 72nd voice coil CL Connection line BL Bridge line SL-1 Signal line SL-2 Signal line MG Magnetic gap MC Magnetic circuit 1 Diaphragm 1-1 to 1-12 First diaphragm to twelfth diaphragm 3 Frame 4 Non-woven fabric 5 Magnetic core or center pole 6 York plate or magnet plate

Claims (5)

  It consists of a dodecahedron having a regular pentagonal unit surface, each unit surface having a plurality of flat magnetic circuits forming an annular magnetic gap, and a regular pentagonal outer shape of the unit surface. A frame for holding a magnetic circuit, a plurality of circular voice coils formed corresponding to each of the magnetic gaps and sequentially connected to each other by connection lines, and a plurality of voices having a regular pentagonal outer shape on a unit surface It consists of a diaphragm that supports the coil facing each of the magnetic gaps, and connects the end point of the voice coil on each unit surface to the start point of the voice coil on the adjacent unit surface via a bridge. An omnidirectional speaker characterized by connecting two voice coils in series.   The magnetic gap and the voice coil of the magnetic circuit are each composed of six concentrically arranged at the center of the regular pentagonal unit surface and the center of the line connecting each vertex and the center. Omnidirectional speaker.   The omnidirectional speaker according to claim 1, wherein each unit surface of the dodecahedron is formed by integrating a diaphragm carrying a voice coil with a frame holding a magnetic circuit.   The omnidirectional speaker according to claim 1, wherein the dodecahedron is configured by a unit surface including a frame for holding a magnetic circuit, and is covered with a diaphragm carrying a voice coil. The diaphragm carrying at least the voice coil is connected to two unit sides other than the first and twelfth unit surfaces connected to the adjacent unit surface only on one side in the unfolded state of all unit surfaces. However, one of the pair of signal lines is connected to one start end of the first unit surface divided into two in the circumferential direction of the first voice coil, and thereafter one of the second to sixth voice coils divided into two. Are sequentially connected to one of the pair of connection lines, and one end of the sixth voice coil divided into two is connected via one of the pair of bridge lines straddling the connecting side between the first and second unit surfaces. Connected to the start end of one half of the seventh voice coil of the second unit surface, and similarly, 2 of the seventh voice coil of the 12th unit surface from the seventh voice coil of the second unit surface. Connect sequentially to one of the pair of connecting lines until one of the divided ends, One end of the 71 voice coil divided into two ends was connected to one end of a C-shaped 72nd voice coil to fold back the connection, and the other end of the 72nd voice coil was divided into 2nd half of the 71st voice coil The first voice is connected to the other end of the first, and then the other half of the 71st to 1st voice coils are sequentially connected via the other of the pair of connection lines and the other of the pair of bridge lines. 3. The omnidirectional speaker according to claim 2, wherein the other end of the coil divided into two is connected to the other of the pair of signal lines to form a one-stroke pattern.

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