TW490987B - Bending wave loudspeaker and method of making the same - Google Patents

Abstract

A loudspeaker is made of a panel 1 supporting bending waves and a transducer 3 covering a substantial portion of the panel surface. At least one constraint, for example a clamp or a mass, is fixed to the panel. Each constraint reduces the mobility of a small area of the panel. Excitation of the transducer excites bending waves in the panel; the constraints discourage simple motion and encourage the production of a plurality of bending waves instead. The constraints can constrain the panel to be excited to produce a good distribution of resonant bending wave modes.

Description

490987 --89113669 V. Description of the invention (1)

Ming Zhi Fan I The present invention relates to a curved radio panel loudspeaker and a method of driving the same. Related Techniques W09 7/0 9 8 42 of the applicant, New Transducers Ltd1 'uncovered the radio wave amplifier, as shown in Figure 1. Generally speaking, a curved radio amplifier includes a panel 1 having at least one exciter 3 coupled to the panel 1 at one or more separate locations or communities. The position or digits of the exciter are selected to disperse the resonant bending radio wave mode to make the panel sound. A conventional art device with a discrete exciter has the difficulty of determining the preferred position of the exciter in some applications, such as taught by w 〇 7 7 / 〇 9 8 4 2 # For example, a loudspeaker may need to be installed In the original equipment, and the required converter location may not be suitable, if another part is involved. In addition, in a transparent loudspeaker using a transparent cardboard, since it is extremely difficult to make a conventional exciter transparent, it may be difficult to place an exciter in a better position without causing visual obstruction. Therefore, it is advantageous to obtain the advantages of better exciter placement without having to install the exciter in a better position consistently. WQ00 / 02417, which is also the applicant, but the priority date is to disclose the use of a transparent board and an exciter coupled to cardboard after this application. It is suggested that the exciter may include a piezoelectric or electret pinched on a panel, but a specific example of such a device is not discussed. Another application for illustrating a transparent flat speaker is GB 2052919 of Hi Tachi Ltd. This application describes a transparent piezoelectric microphone having a piezoelectric layer on one side. As explained in GB 2052919,

O: \ 65 \ 65236.ptc Page 5 490987 _Case No. 89113669_ Year Month Revision_ V. Description of the invention (2) The problem is that the loudspeaker operates only in a narrow frequency band. Although in G B 2 0 5 2 9 1 9 some improvements have been achieved by choosing the oval shape of the loudspeaker panel, the effect is still not obvious. The aforementioned best effect has a small sound output from 1 KHz to 3 KEz and a very narrow band. G B 2 0 5 2 9 1 9 reveals that only one point on the substrate is excited, unlike the W09 7/0 98 4 2 device where multiple frequency modes can be excited. However, the use of a good sound output in one of the frequency ranges of the resonant bending radio wave mode causes the exciter to excite a number of resonance modes dispersed in frequency. Therefore, in addition to their practical use in the most basic applications, their performance needs to be improved. SUMMARY OF THE INVENTION According to a first feature of the present invention, there is provided a curved radio wave amplifier capable of supporting curved radio waves and having opposite sides, a converter extending to a large part of one side of the panel and coupled to the surface of the panel, and at least The restrainer is coupled to at least a discrete small area of the panel movement of the panel, so the activation converter material can excite multiple resonant bending radio wave modes of the panel. Instead of placing the converter in a predetermined position, the converter is suspended from a sufficient portion of one of the panel areas and restrains the panel at one or more restraint positions. A large part of the panel surface may be at least 60%, preferably 75% or even more than 90% of the panel area. The larger the part, the larger the converter and therefore the larger the output power. This is particularly useful when the switching device only provides a small action for one unit of input, which is often the case with piezoelectric materials. Most of the better ones are substantially the entire surface of the panel, and the small area can be much smaller than the area of the panel. Each small area can be no more than 10% of the panel area, preferably no more than 1%

O: \ 65 \ 65236.ptc Page 6 490987 Case No. 89113669 Month Amendment V. Description of Invention (3). In addition, the beamer can support the panel as before. The problem is that the mode of the board surface is switched. 5 Each one does not produce extremely high harmonics. The piezoelectric excitation described in the present invention can have a smaller area than the panel. A linear ruler with a width of 20% is greater than 10% and further preferably is not greater than 4%. It is difficult to bend, so it is extremely difficult to drive one of the panels. It is not suitable to support materials which are particularly suitable for vibrating bending waves in a predetermined operating frequency range. The applicant believes that the exciter in GB 2052919 that produced an adverse effect did not excite a good resonant bending radio wave mode distribution. The loudspeaker provides a localized restraint that extends to the surface converter, allowing reasonable or good dispersion of multiple resonant bending electronics, including the surface of the conversion equipment, extending over a large portion of one face of the panel. The converter can be added to the opposite side of the panel. This method, called a π-coupled π converter, can include a large portion of the first to the first converter material extending from the opposite side of the panel. The device can be packed and coupled to the surface. The one-step converter is one of the step-up converters. The coupling configuration provides several additional advantages. First, the plate is sandwiched between two converters. These pieces can be configured such that the top piece shrinks and the bottom piece expands to provide the plate with a true bending pressure, rather than the linear shape that occurs when a device is applied to only one piece of converter material. Stress (known as coupling). In addition, the panel and the converter plate itself constitute a unit of a unit, achieving a good distribution of the harmonic bending radio wave mode. The restraint may be a mass fixed to the panel, such as buried on one side of the panel. The restraint can also be a rigid coupling, which couples a small area of the panel to the panel to substantially hinder the movement of the small area.

O: \ 65 \ 65236.ptc Page 7 490987 Case No. 89113669 Amended 5. Description of the invention (4) The position of the restrictor can be selected to make the resonant bending radio wave mode of the constrained panel, especially at the lower end of the operating frequency range , Facilitates a desired sound effect. In fact, the position and parameters of the restrictor can be selected to optimize the sound output. The position of the restraint can be determined mathematically or numerically, or even systematically. The restraint can be placed in a convenient position to install a conventional small actuator on a free panel. Instead of driving a free panel in a discrete position, the panel is driven through a large part of its surface and is in a suitable driving position ‘pinned’ (p i η n e d) using a local converter. Therefore, the non-localized converter for a loudspeaker according to the present invention effectively reverses a conventional discrete mode loudspeaker. In some specific examples, the restraint may be located at the exit edge, that is, at least about 20% from the edge of the panel. The width refers to the width that passes through the panel in a direction orthogonal to the length of the panel. Each restrainer can be located in an asymmetric position. If the panel is in a symmetric form with one or more axes of symmetry, the restraint can symmetrically separate one or more axes, for example at least 3% of the panel width, preferably at least 5%. This constraint position is not necessarily possible. Therefore, each restraint can be located at the edge of the panel, or at least 20% of the distance not passing further from the edge. This is particularly important in cases where the center area of the panel is restricted to a converter.

Each converter material can be sandwiched between a pair of electrodes to form a converter diaphragm. The electrodes can be on either side of a converter diaphragm, and the electrodes can be converters. A suitable converter electrode material is indium tin oxide. A converter film can adhere to one or more faces of the panel. The pair of electrodes

O: \ 65 \ 65236.ptc Page 8 490987 Case No. 89113669 Revision V. Description of the invention (5) One electrode can cover most of one side of the panel, and the mechanical light-duty converter material is on the panel. The converter material can change shape when electricity is applied. Therefore, the material may be a piezoelectric material such as lead lanthanum titanate (PL ZT) or polyvinylidene fluoride (PVDF). In some specific examples, the panel and the piezoelectric material may be transparent. This situation is particularly applicable to converter panels. The panel can be suspended or otherwise supported by a bracket that has a small effect on being away from the resonance mode.

Alternatively, the panel may be supported by the restraints, or the panel may be conventionally on a frame of a curved radio wave panel. In the latter case, each of the restrainers may simply have a function of restricting the movement of the panel at a predetermined position. On the other hand, a method of manufacturing a curved radio wave converter having one of the opposite sides includes: determining the shape, size, and proportion of a panel; selecting one of the converter materials that should be added to a selected large area of the panel; Characteristics; selecting the position of at least one small area and the parameters of at least one of the restraints that should be added to at least one small area of the panel so that the panel provides a practical sound effect; and

A converter is manufactured from applying a selected converter material to a selected portion of a large portion of a face of the panel, and applying a selected panel constraint using the selected restrictor parameters to the selected small area. Brief description of the drawings In order to further clarify the present invention and purely exemplification, specific examples of the present invention will be described with reference to the drawings.

O: \ 65 \ 65236.ptc Page 9 490987 Case No. 89113669 Month Amendment V. Description of Invention (6) Figure 1 shows a traditional curved radio wave panel loudspeaker. Figure 2 shows a loudspeaker according to the invention. Fig. 3 shows a side view of a loudspeaker according to a specific example of the present invention. Fig. 4 shows a top view of a loudspeaker according to another embodiment of the present invention. Fig. 5 shows a flowchart of a method of manufacturing a loudspeaker according to the present invention. FIG. 6 shows a side view of a panel according to another embodiment of the present invention. FIG. 7 shows the sound output of the loudspeaker λ according to the specific example of FIG. 6. FIG. 8 shows the terminal impedance of the loudspeaker according to the specific example of FIG. 6. Brief description of component reference symbols 1 panel 3 converter layer 5 top electrode 7 bottom electrode 9 signal connector / electrical input line 11 quality 1 3 frame 1 5 foam support 17 soft elastic frame 19 top surface of the panel 21 bottom surface of the panel 2 3 Top of panel

O: \ 65 \ 65236.ptc Page 10 490987 Case No. 89113669 Rev. V. Description of Invention (7) 2 4 Axis 2 5 Bottom of the panel 5 1, 5 3, 5 5, 5 7 Manufacture of loudspeakers Method step 6 1 Upper film 6 3 Lower film C 1-C 6 The position of the restrictor is detailed as shown in the general name shown in FIG. 2. The loudspeaker according to the present invention includes a panel 1 with an opposite top 2 3 and a bottom. 2 5. The panel need not be flat, but

Made into a form required for a particular application. A converter layer 3 is provided on an actual part of one side of the panel. The signal connector 9 provides a microphone input, which is generally in the form of an electrical signal. Either a clamp or a mass of at least one restraint can pressurize one of the C 1 -C 6 positions shown. The mass-loaded panel is fixed or engaged with the mass; in order to fix the panel, the panel is partially coupled to a rigid support. The location of the selection constraint will now be briefly discussed. The process according to the present invention is achieved in a reversal manner, such as W097 / 09842, in a traditional approach in a decentralized mode. The panel is not driven at a selected point. The panel is driven on one substantial part of the panel surface and one or more discrete locations are printed.

One good starting point for the restraint position is the better driving position in W 0 9 7/0 9 8 4 2. Therefore, the suitable constraint position is generally separated from the substantial line interval of one of the lower frequency node lines, and these intervals are separated from the symmetrical edge and axis under normal conditions. The restraint is at a distance C 1 of a panel width of at least 10% from the panel edge

O: \ 65 \ 65236.ptc Page 11 490987 Case No. 89113669 Month Amendment V. Description of Invention (8) and C4 positions may be suitable. The selected position can also be at least 5% of the panel width parallel to the edges of the rectangle and past the midpoint of the panel. If a restraint position is not practical inside the panel, use a restraint position such as C2, C3, C5 or C6. When designing a panel, the following method as illustrated in Fig. 5 can be used. First, first determine the shape, scale, and parameters of a panel (step 51); these steps are determined by other factors that apply to the configuration of the loudspeaker. Then, the converter material is selected (step 5 3). Then select the position where the converter material is applied, and this point can be as large as possible to make the sound output. The designed panel is not easy to produce acceptable sound effects. To solve this problem, the position of at least a small area and the parameters of at least one restraint should be added to the panel and should be selected (step 5 5). This step can be implemented by calculations, such as finite element analysis or systematic experiments. Restrictor parameters and positions can be selected to produce a usable sound output. Achieve the consistent use of New Transducers illustrated in WO 99/41939 and include in this description for reference. The specific example of the present invention in which the panel needs to provide a restraint or clamp inside the panel may not be applicable because the restraint clamp may interfere with the converter of all loudspeakers. In these cases, it may be advisable to place the panel clamp at one or several points around the edge of the panel. A suitable position is disclosed in a suitable drive position (New Transducers Ltd) in WO 99/37121, and a suitable clamp position (New Transducei's L t d) in WO 9 9/52 3 24. Both documents are included in this article for reference. A position around the distance of 0.38 to 0.50 along the length of an edge may be particularly suitable.

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Page 12 490987 Case No. 89113669 Amendment V. Description of the invention (9) The clamp is particularly suitable for providing a restraint at or near the edge of the restraint. The closer to the center of the panel, the more convenient it is to provide a constraint by adding mass. However, these options can be varied to suit any particular design. After the appropriate position and type of the restraint has been selected, a panel such as the selected converter material is added to a large part of one side. Each selected constraint is added to the panel in each small area using the selected constraint parameters. Purely for illustration, a specific example of the present invention will be described with reference to FIG. 3. The panel 1 having opposite top and bottom surfaces (19, 2 1) has one piezoelectric transformer material of lead lanthanum titanate (PLZT) added to the center region of the top surface 19 of the panel 1. The piezoelectric layer 3 is sandwiched between the top and bottom electrodes 5, 7 to constitute an electric input line 9. The bottom electrode 5 covers the center area of the panel 'which occupies a large part of the panel area and couples the converter layer 3 to the panel. The panel is mounted in a frame 13 on a soft elastic frame 17 connected to the center portion of the bottom surface 21 of the panel. To load the panel at position C4 (Figure 2), mass 1 1 is fixed to the panel at this position. In order to install a clamp at position C 6 (Fig. 2), the panel is rigidly coupled to the frame 13 by the rigid coupling member 15 at this position, and the elastic frame 17 is not used elsewhere. Now referring to FIG. 4, another converter is described. A specific example. A lightweight multi-media converter has a weight of 10g and an aspect ratio, that is, a rectangular panel with a ratio of length to width of 1.3: 1. The weight of a heavy restrainer 1 1 is the length of the panel from one end. The position of 4/9 of the position and 3/7 of the width of the panel from the edge are fixed behind the panel, that is, spaced from the axis 24. Essentially all front aspects of the upper panel are covered by the aforementioned three-electrode switch structures 3, 5, 7. The electrode switches are spaced inward from the edge of the panel. Panel is supported on

O: \ 65 \ 65236.ptc Page 13 490987 __Case No. 89113669 ___ J | _S_Amendment __ 5. Description of the invention (10) A foamed stent 15. Another preferred embodiment will now be described with reference to FIGS. 6 to 8. In this specific example, two piezoelectric layers are provided, which are located on each side of the panel 1, respectively. Therefore, the panel is a link. The rectangular panel 1 is made of 150 mm long and 13 5 mm wide Rohacell. Two commercial uses have a polyvinylidene fluoride (PVDF) film provided by the manufacturer connected to the panel ', which are located on both sides of the panel, so the panel is sandwiched. The film used was manufactured by Pennwa 1 ΐ corporation, 〇f Norristown, PA, USA, and sold as nKynar Piezo Film sample type S028Kn. The film includes a polyvinylidene fluoride sheet sandwiched by a silver electrode. Each piece of PVDF covers about 90% of the area of the square electrode 1 ′ irrespective of the edges. The adhesive used is thermoplastic polyurethane adhesive "pur〇Η-2 5 g ° The film used is slightly anisotropic, and when a voltage is applied, it bends slightly in one direction, that is, the active direction, and is greater than orthogonal to the active direction. Front and The rear film is calibrated with the active direction parallel to the long edge of the panel. Used as a restraint 1 · 2 g mass ΐ 加 Add 3/7 of the panel length from one end of the panel and 4/9 of the width from one edge of the panel 1 For the panel. For comparison, the panel mass is 7 g. The mass scale is small, so it covers only a small area of the panel area.

Utilizing the known characteristics of the panel or parts, the following estimates of the panel ’s bending axis and piezoelectric layer are estimated to be 0.9 N m per unit plane, 1.78 kg / V, and The mechanical resistance is now 10.2 Ns / m. The coincidence frequency, which is the frequency of the sound in the panel air, is estimated to be 26.7 KHz. base

苐 Page 14 490987 Case No. 89113669 Revision V. Description of the invention (11) The frequency is approximately 1 2 0 Η z. The electrodes 5, 7 of the upper film 61 and the lower film 63 are electrically connected in parallel. After conducting an experiment, the sound pressure level film of the meter was used to generate a frequency function of the loudspeaker at a width of 0.5 m produced by the 20V input parallel to the connected. The effect is shown in Fig. 7. A loudspeaker produces a frequency-rate response that is practical and even for a wide frequency range. It should be noted that no converter is used in the test so that the sound output obtained indicates good efficiency. As mentioned earlier, the use of slightly the same anisotropic film means that certain low-frequency resonance modes of the panel are less strongly excited. This results in a power drop below approximately 1.5 K Hz seen in FIG. 7. If this is a problem, the pair of films can be mounted on each side of the panel, each pair of films having orthogonal active directions. In this way, four faces can be used. Fig. 8 shows the electrical impedance of the two piezoelectric films. As shown in the figure, the impedance is higher than lower frequencies due to the characteristics of the piezoelectric transducer. The invention is not limited to the specific examples described above, and various changes can be made without departing from the principles of the invention. For example, any suitable converter material for any conversion device that responds to electrical signals can be used, including the aforementioned PLZT or polyvinylidene fluoride (PVDF). In fact, the converter can be configured as a micro-actuator, including a micro-actuator combination that is a substantial portion of the panel surface.

The electrode may be made of any suitable conductive material, such as silver, conductive polymer, copper or the like. The electrodes may be converter electrodes, for example made of indium tin oxide. Position fine FM and restrictor types are possible, calculate the correct position or

O: \ 65 \ 65236.ptc Page 15 490987 Case No. 89113669 Revision V. Description of the invention (12) System analysis effect. A substance can be fixed to the panel by various fixing means, such as adhesive, adhesive tape, a screw or nut, or an alternative fixing as shown. A substance container can be embedded in the panel, such as a heart body and the epidermal structure. A clamp can also be fixed on one or two sides, or near the center or on the periphery.

π clamp π — The word is not limited to a conventional clamp, and any fixing device that fixes a local area of a panel can be used. For example, a rigid coupling element may be rigidly connected to a point on the panel to achieve a rigid frame, or a portion of the panel may be sandwiched between clamp elements. The frame itself can be made to clamp part of the panel. The skilled person will suggest other methods of clamping the panel, that is, substantially preventing movement of an area of the panel. Panel materials that can support curved radio waves and their dimensions and shapes can also be changed as needed.

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Claims (1)

490987 Case No. 89113 [Monthly Amendment VI. Scope of Patent Application No. 1 · Upper; Plate Bending and Vibration 2. Container Packaging. 3. Conversion 4. Electrode panel 5. Equipment 6. Material 7. An approximation 8. An approximation of a curved one panel and one transition of at least one movement, if the application mode includes extensions, such as the application, the material is applied as one of the applications The conversion of the application materials is as transparent as the application, and the application of the beam device is such that the application of the beam device is to block the surface curved radio wave amplifier, including: 'Can support Zeng Qu radio waves and have opposite sides, the device extends on one of a panel The larger part is coupled to its restrictor, which fits in at least a small area of the panel and restricts the activation of the converter material, which can stimulate multiple harmonics of the panel. The curved radio amplifier of the first item of the patent Among them, the curved radio wave amplifier, which is converted to a large part of a conversion device patented in the second range of the panel, is sandwiched between a pair of electrodes. The curved radio amplifier of item 3 of the patent, wherein the pair of electrodes cover a large part of one face of the panel and the mechanical coupling device material. The curved radio wave loudspeaker of item 2 of the patent, wherein the piezoelectric material is converted. Patent No. 5 is a bending radio wave loudspeaker, which is a piezoelectric one. The curved radio amplifier of item 1 of the patent scope has at least one mass. The curved radio wave loudspeaker of item 1 of the patent scope is at least engaged with a rigid coupling member of a small area of the panel to move through the small area of the panel. O: \ 65 \ 65236.ptc Page 18, 490987, Case No. 891136, Amendment 6. Application for patent scope 9. For the curved radio amplifier of the first patent application scope, most of the panel area is at least 7 5 %. 10. The curved radio wave loudspeaker according to item 1 of the scope of patent application, wherein each small area has a linear dimension of not more than 20% of the panel width. 11. The curved radio wave loudspeaker according to item 1 of the scope of patent application, wherein each small area has an area not larger than 1% of the panel area. 1 2. The curved radio amplifier of item 1 of the patent application scope, in which the relative converter is installed, is located on a large part of the panel area, and is located on the opposite side of the panel. 1 3. The curved radio wave amplifier according to item 12 of the patent application scope, wherein the converter includes a piece of conversion equipment sandwiched between a pair of conventional electric switches. 14. As in the curved radio amplifier of item 1 of the patent application scope, at least one of the restrictors is located at least 20% of the panel width from the edge of the panel. 15. The curved radio wave loudspeaker according to item 14 of the scope of patent application, wherein the panel has at least one axis of symmetry, and the width of the panel between the at least one restrictor and the axis of symmetry is at least 4%. 16. The curved radio wave loudspeaker according to item 1 of the patent application scope, wherein the panel is supported by the restraint. 1 7. The curved radio wave loudspeaker according to item 1 of the scope of patent application, wherein the resonant curved radio wave mode of the panel is constrained by at least one restrictor or even constrained in its frequency. 1 8. — A method of manufacturing a curved radio wave loudspeaker having one of the opposite faces, including: O: \ 65 \ 65236.ptc Page 19 490987 _Case No. 89113669_Year_Month__ Sixth, the scope of patent application determines the shape, dimensions and characteristics of a panel; choose the majority of the selected part that should be added to one side of the panel A piece of converter material; choose at least a small area location and at least one restraint that should be added to at least a small area of the panel, so the panel provides effective sound generation; Most of the selected panels manufacture a loudspeaker, and the selected panel parameters are used to create the selected panel constraint in the selected small area. 19. The method according to item 18 of the scope of patent application, comprising selecting at least substantially the most suitable curved radio wave loudspeaker at least one position and parameters of the sound output of the restraint at a predetermined operating frequency range. 20. The method as claimed in item 18 or 19 of the scope of patent application, including selecting the position and parameters of at least one restrictor to substantially achieve the most suitable stable sound distribution of the resonant bending radio wave mode of the panel in a predetermined operating frequency range . O: \ 65 \ 65236.ptc Page 20