TW201717662A - Loudspeaker component including an accommodating room, a diaphragm, a screening element, and a plurality of porous granules - Google Patents

Abstract

A loudspeaker component includes an accommodating room, a diaphragm, a screening element, and a plurality of porous granules. The accommodating room is defined into two chambers by the diaphragm. The chamber in which the screening element is located is segmented into a filling space. The plurality of porous granules are filled in the filling space according to a filling ratio. A single porous granule includes a plurality of porous particles and is formed by combining the plurality of porous particles through a granulation procedure. As such, the porous granule can absorb air so as to allow the loudspeaker component to keep a miniature size and provide a superior electroacoustic feature.

Description

Speaker component

The present invention relates to a speaker component, and more particularly to a microelectromechanical speaker component having a miniature size and superior electroacoustic properties.

In response to the market demand for miniaturization of consumer electronics, Micro Electro Mechanical Systems (MEMS) technology has evolved to develop MEMS speakers with acoustic waves converted to electrical signals in the field of electro-acoustics; MEMS speakers are maintaining miniature dimensions. At the same time, it also has better characteristics such as sex ratio, sensitivity, temperature stability, etc., so it is widely favored by consumers. However, miniaturization is both an advantage of MEMS speakers and a relatively innate limitation. For example, in the MEMS speaker chip, the space between the front cavity and the back cavity is quite narrow. In the case of limited space, the air resistance is too large, which will affect the vibration of the diaphragm. In particular, the back chamber is a space for the external sound waves to resonate, and the low frequency sound wave. It requires a larger resonance space than other frequency bands. Therefore, it is one of the goals pursued by the industry to amplify the back cavity space to obtain a better sensitivity and frequency response of the MEMS speaker chip.

Therefore, the industry proposes a way to improve the back cavity resonance. A porous material is arranged in the back cavity, and the hole can adsorb air. The air adsorbed by the porous material simultaneously drives the porous material to vibrate when vibrating, thereby changing the resonance inside the back cavity. The frequency, the effect is equivalent to increasing the volume of the back cavity, thereby achieving an enlarged back cavity within a limited size.

US Patent No. 8,335,333 B2, published on December 18, 2012, patent name The so-called "LOUDSPEAKER SYSTEM", the applicant Panasonic Corporation disclosed that there are a plurality of particles in the back cavity, the particles are connected by an adhesive to maintain the particle spacing, and the particles can be selected from materials with porous properties, such as carbon, Ceria, zeolite, etc. Therefore, the pores of the single particles themselves, as well as the voids between the particles and the particles, can be filled with air.

U.S. Patent "LOUDSPEAKER SYSTEM WITH IMPROVED SOUND", published on July 4, 2013, the disclosure of which is incorporated herein by reference in its entirety by its its its its its The zeolitic material is in the form of particles and the mass ratio of cerium/aluminum of the zeolite particles is more than 200, and the particle size distribution of the zeolite particles is 0.2 mm to 0.9 mm. The granule material has its own characteristics and process design, and can form pores of different sizes. The pore size distribution is from 0.7 μm to 30 μm. The air filled in the pores of the zeolite simultaneously drives the zeolite to vibrate in the back cavity, changing the resonance frequency of the back cavity, thereby virtualizing the amplified back cavity.

A similar concept is also mentioned in US Patent No. 8,687,836 B2, issued on April 1, 2014, to the US patent "LOUDSPEAKER SYSTEM". Applicant Bose Corporation discloses a cerium-based zeolitic material with at least metal aluminum mixed with a 矽/aluminum molar ratio between 200 and 400; likewise, this material is also placed in one that can be formed The space of resonance.

U.S. Patent "PRESSURE ADJUSTOR AND METHOD OF MANUFACTURING THE SAME, SPEAKER DEVICE USING THE PRESSURE ADJUSTOR, ELECTRONIC DEVICE, AND VEHICLE" of US Pat. No. 8,767,998 B2, issued on July 1, 2014, the disclosure of which is filed by the applicant Panasonic Corporation A piece of woven material is placed in the back cavity, and the woven material is adhered with a plurality of tiny carbon particles by an adhesive to create a woven material that can absorb air.

However, although the prior art in which the porous material is provided in the back cavity has been preceded, there is still room for improvement in the industry, for example, the pores of carbon itself are not easily formed, and the adsorption effect is not good; the zeolite is a crystalline material, and the crystal forming process still requires considerable The precision and time make the production cost increase; in addition, the crystalline material with gas adsorption function has obvious aging degradation, resulting in a short service life. Therefore, while taking into account the superior micro-size and electro-acoustic properties, further pursuit of process efficiency and cost reduction is still an urgent issue for the industry.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a speaker element which, while being limited by the type of speaker, can maintain superior micro-size and electroacoustic properties while further achieving higher process efficiency and lower process/feedstock costs.

To this end, the present invention provides a speaker component comprising a chamber, a diaphragm, a screen element, and a plurality of porous particles. The chamber defines first and second chambers by a diaphragm, wherein the diaphragm is separated from the first chamber in the same direction as the sound exiting chamber, and the diaphragm is spaced apart from the second chamber relative to the front chamber The chamber is a rear sound chamber, and the screen element is disposed in the rear sound chamber and a filling space is partitioned so that the filling space and the diaphragm are respectively located on opposite sides of the screen element. A plurality of porous particles are filled in a filling space of the rear acoustic chamber in a filling ratio, wherein each of the porous particles is formed by combining a plurality of porous particles, and the filling space in the acoustic chamber is vibrated.

Therefore, the speaker component provided by the present invention, particularly for use in a compact, power-saving earphone or a micro-speaker in a hand-held device, causes the resonance frequency of the sound to move to the middle and low frequencies in a small mechanism space, and In the extended bandwidth range, the performance of its sound details can be fully presented; in addition, the speaker elements of the present invention are in a limited chamber In the structural space, the porous particles can be freely vibrated independently of each other in the filling space in the rear acoustic chamber, and the total amount of specific areas of the particles is increased by the vibration of the particles to achieve a virtual enlarged back. The effect of the cavity, which in turn enhances the low frequency performance of the sound, to maintain a small size and excellent acoustic properties. Further, the particles may be composed of a porous amorphous material, and the amorphous material is more likely to adjust the particle size and size of the porous particles or particles by the process than the other crystalline materials, and The fill ratio in the fill space of the chamber increases the reliability of the speaker components and maintains low process costs.

10‧‧‧ Room

11‧‧‧ first chamber

12‧‧‧Second chamber

121‧‧‧Unfilled space

122‧‧‧filled space

20‧‧‧Densor

30‧‧‧ Screening elements

40‧‧‧Porous particles

50, 50a, 50b‧‧‧ particles

R‧‧‧ particle size

S100, S200, S300, S101~S104, S201~S202‧‧‧ steps

60a‧‧‧suspension solution

60b‧‧‧colloidal fluid

70a‧‧‧ atomizer

70b‧‧‧Quick Freezer Room

71b‧‧‧Agitating mechanism

70c‧‧‧vacuum room

70d‧‧‧Condensing room

71d‧‧‧Condenser

1 is a schematic structural view of a first embodiment of a speaker component of the present invention; 2 is a schematic diagram of resonance of a back cavity of a speaker component; and FIG. 3 is a schematic structural view of a second embodiment of a speaker component of the present invention; FIG. 5 is a schematic diagram of the fabrication of the speaker elements of FIG. 1; FIG. 6 is a schematic diagram of the process of step S200 of FIG. 3; FIG. 7 is a volume of the same filling space, and different filling ratios. The impedance curve is shown below; Figure 8 is the impedance curve of the particle size distribution; and Figure 9 is the impedance curve of the volume with the same filling ratio and different filling spaces.

Referring to FIGS. 1-2, a first embodiment of a speaker component of the present invention includes a chamber 10, a diaphragm 20, a screen element 30, and a plurality of uniformly sized porous particles 40. . The diaphragm 20 is disposed at the chamber 10 and defines a first chamber 11 and a second The chamber 12; the first chamber 11 is the same acoustic chamber as the sounding direction S, and the second chamber 12 is the rear acoustic chamber with respect to the front acoustic chamber. The sieving element 30 is disposed in the second chamber 12 and defines an unfilled space 121 and a filling space 122; in detail, the filling space 122 and the diaphragm 20 are respectively located opposite to the sifting element 30. On the side, the filling space 122 is separated from the diaphragm 20 by a predetermined distance d between the screen element 30 and the diaphragm 20, and the chamber 10 determines the filling space 122 in the chamber 10 according to a volume ratio. The volume occupied by the filling space 122 determines the volume filled by the porous particles 40 in the filling space 122 according to a filling ratio.

Wherein, the opening of the first chamber 11 is merely illustrative and not limited to the embodiment; wherein the porous particles 40 themselves are formed by combining a plurality of porous amorphous particles 50 with an adhesive, and the porous The particles 40 are independent of one another and can vibrate in the fill space 122 located within the second chamber 12.

Since the amorphous material is amorphous without grain boundary and long-range regularity, it is not necessary to have a stable growth environment and sufficient crystal growth time, so the amorphous material requires less time and cost. Lower; the aforementioned amorphous particles 50 are made of a porous amorphous material having an amorphous state (having no grain boundary and long-range regularity, and having only a short-range regularity). The foregoing materials may be selected from porous materials such as activated carbon, Zeolite, SiO ₂ , alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), magnesium oxide (MgO). , one of triiron tetroxide (Fe ₃ O ₄ ), molecular sieve (Molecular sieve), fullerene (Fullerene) and carbon nanotube (Carbon Nanotude) and a group thereof; and the aforementioned adhesive A powdered resin material (Powdery Resin Material) or a fibrous resin material (Fibrous Resin Material) can be used. In the present embodiment, the particle diameter R of the porous particles 40 is 100 μm to 500 μm; the particles 50 are made of amorphous ceria, and the particle diameter may range from 10 nm to 100 μm; in addition, the porous particles 40 are independently and randomly stacked, are not arranged in a certain spatial order, and are independently and freely vibrated in the filling space 122 of the second chamber 12 (rear sound chamber) in which they are located, resulting in being filled in the filling space 122 as shown in FIG. The phenomenon of free vibration inside.

The screening element 30 of the present invention is disposed in the filling space 122 of the second chamber 12 in which the porous particles 40 are located, such that the porous particles 40 are spaced apart from the diaphragm 20 by a predetermined distance d as described above to avoid the diaphragm 20 When vibrating, it is disturbed by the porous particles 40 to generate an abnormal sound. The sieving element 30 is composed of a gas permeable material to maintain a smooth venting, and to block the contact of the porous particles 40 with the diaphragm 20 to cause component damage. The sieving element 30 has a plurality of meshes 31, and the size of the meshes 31 is smaller than the particle size of the porous particles 40, and the size of the meshes 31 is at least 100 μm or more, so that the sieving element 30 is ventilated smoothly, and the air can still be The corners of the second chamber 12 are unconstrained and free to vibrate.

The resonance frequency affecting the second chamber 12 depends at least on the porosity of the porous particles 40 itself, the particle size distribution of the porous particles 40 itself, the filling ratio of the porous particles 40 in the filling space 122, and the filling space 122. Factors such as the volume ratio of the chamber 10.

Since the porosity of the porous particles 40 itself depends on the particles 50 and the manner in which the particles 50 and the particles 50 are stacked and formed, the implementation of the particles 50 and the porous particles 40 of the present invention, and the speaker elements are provided as described above. For the implementation of the pore particles 40, refer to the steps of FIG. 5 as follows: in step S100, porous amorphous cerium oxide particles 50 are formed; and in step S200, the porous amorphous cerium oxide particles 50 are granulated. The porous particles 40 are formed; and in step S300, a plurality of porous particles 40 are filled into the second chamber 12. Wherein, in step S100, the inventors synthesize porous amorphous ceria by a gel method, and different concentrations and times produce different pore sizes and ratios, and the process is summarized as follows: First, in step S101, three solutions are prepared, one of which is a polyethylene glycol (PEG) solution, which is formed by dissolving 4 g (g) of PEG in water and stirring and dissolving in this embodiment; A sodium (Sodium Silicate, SS) solution, which is formed by dissolving 16 g of SS in water in this embodiment; and an Acid Buffer Solution, in this embodiment, citric acid and hydrogen peroxide. A solution of sodium hydroxide mixed. Next, in step S102, the above three solutions are mixed and allowed to stand for several hours, which is preferably 2 hours. Then, proceeding to step S103, the aforementioned mixed solution is subjected to a hydrothermal treatment, which is preferably placed at an ambient temperature of 100 degrees Celsius for several hours to adjust the physicochemical properties of the reactants without destroying the reactant structure. Finally, in step S104, the reactants are filtered and subjected to calcination at different temperatures (at least once) to obtain amorphous cerium oxide particles in a powder state, and each of the amorphous cerium oxide particles 50 is covered in size. Different apertures.

The use of the gel method to produce the porous amorphous ceria particles 50 in a powder state can achieve at least two effects: first, the process is convenient and efficient; and the purity of the raw material of the crucible is not excessively required. Therefore, the raw materials are easier to obtain, the prices are reasonable, and the cost of raw materials can be greatly reduced.

In step S200, the granulation process is granulated by a spray freezing process and a freeze drying process (Freeze Drying Process); in step S200, the powdered amorphous cerium oxide particles 50 are each After a procedure, it is possible that the adhesive gradually becomes larger due to the bonding of the other particles 50; the process is as follows: in step S201, the amorphous amorphous ceria particles 50 are first mixed with an adhesive and a dispersant. Suspension solution 60a, temporarily called the particles in the intermediate state of amorphous ceria particles 50a; mixed with a pressurized gas (Air), so that the suspension solution 60a is sprayed into the atomized state through an atomizer 70a Quickly freezing the chamber 70b; at this time, the suspension solution 60a is gelatinized into a gel The fluid 60b allows the amorphous ceria particles 50a in the intermediate state to be combined with the amorphous ceria particles 50b which are larger particles by the sufficient action of the freezing environment and the adhesive. The quick freezing chamber 70b is provided with a stirring mechanism 71b at the bottom, which can stir the colloidal fluid 60b in the chamber to increase the chance of the intermediate amorphous cerium oxide particles 50a contacting each other, and the intermediate amorphous cerium oxide particles. 50a is more likely to form a semi-finished product having larger amorphous ceria particles 50b.

Next, the step S202 is performed to freeze-dry, and the semi-finished amorphous ceria particles 50b are placed in a vacuum chamber 70c, and the moisture is sublimated by the low temperature and the vacuum environment, and the moisture is taken from the vacuum chamber 70c to the condensation chamber 70d. The condensation is carried out by the condenser 71d, and the original amorphous ceria particles 50b and the colloidal fluid 60b form the porous particles 40 after freeze-drying. The temperature of the vacuum chamber 70c is between the temperature of the rapid freezing chamber 70b and the condensation chamber 70d, so that the moisture of the colloidal fluid 60b can be vaporized when entering the vacuum chamber 70c. The fast freezing chamber 70b is filled with liquid nitrogen to maintain the chamber temperature at 196 degrees Celsius (-196 ° C) below the boiling point of liquid nitrogen, while the condensation chamber 80 is controlled at minus 30 degrees Celsius (-30 ° C). The granulated product is an irregular irregular porous particle 40 having a particle diameter ranging from 100 μm to 500 μm; wherein the binding between the powdered amorphous cerium oxide microparticle 50 and the microparticle 50 is an adhesive. In combination, and the particles 50 may have different particle sizes from one another, the spacing between the particles 50 and the particles 50 may also vary.

It should be noted that the particles 50 are amorphous cerium oxide in a powder state, and the particles 50 are made of an amorphous material, and the particle size is easier to control and cost more than the crystalline material. Low; and the porous particles 40 combined by a plurality of particles 50 having a uniform particle diameter are more effective in adsorbing air because the stacking is more stable and denser, thereby increasing the specific surface area. Specifically, in the present embodiment, the powdery amorphous ceria particles 50 have a particle size distribution of 2 μm or less or a distribution of 1 to 2 μm, or the same porous particles 40. The particles 50 can distinguish between a maximum particle and a minimum particle, and the difference in particle size between the largest particle and the smallest particle is less than 1 μm, or both of the foregoing conditions coexist. The foregoing specific limitation imposed on the particle size of the particles 50 is to provide the porous particles 40 combined by the particles 50 having similar particle diameters to have a larger specific surface area, thereby providing a better gas adsorption function; In the granulation, the particles 50 having uniform particle diameters can be stacked on each other to form a dense packing, so that the structures and sizes of the respective porous particles 40 are relatively uniform, and the particles 40 are more easily stacked in addition to the specific surface area. The result of the shape of the sphere. Further, by the porous particles 40 formed by the foregoing process, the weight ratio of the adhesive to the porous particles 40 is 5% to 10%.

In step S300, a plurality of porous particles 40 are filled into the filling space 122 of the second chamber 12 of the speaker element. Since the amorphous fine particles 50 do not have defects in the crystalline material, they are not easily deformed, and their physical properties and chemical properties are not directional, so that they have higher strength and resistance than crystalline materials, so that the amorphous particles are filled. The speaker elements of the particles 50 have a higher product reliability.

Please also refer to Figures 7-9 for the applicant's evidence of the other experiments provided by the other factors affecting the resonant frequency of the second chamber 12. As shown in Fig. 7, at the volume ratio of the same filling space 122, the porous particles 40 occupy at least 50% of the filling space 122, which can provide a better resonance frequency; and it can be further seen from Fig. 7 that other possibilities are possible. In the case of the porous particles 40, the filling ratio of the filling space 122 may be 70% to 90%, and the resonance frequency of the filling ratio of 80% is optimal; that is, the diaphragm 20 is pushed in a fixed mechanism space. The resonance frequency of the sound can be moved to the middle and low frequencies to achieve the benefit of widening the bandwidth range, and the total harmonic distortion (Total Harmonic Distortion) is reduced, and the power consumption of the vibration system can be improved. In other words, in the speaker element of the present invention, the volume of the same filling space 122 In the case of the porous particles 40 of the same size and the same size (specification), the filling ratio of 50% or more can effectively move the resonance frequency to the middle and low frequencies. According to the foregoing, the porous particles 40 can increase the total surface area of the porous particles 40 as long as they can adsorb the gas and are free to vibrate independently of the filling space 122, and further occupy the filling ratio of the filling space 122. More than 50%, the resonance frequency can be shifted to the middle and low frequencies as shown in Fig. 7, thereby achieving the technical effect of virtually expanding the second chamber 12 (the rear sound chamber).

As shown in Fig. 8, in the speaker element of the present invention, in the case of the same volume ratio and filling ratio, filling the different sizes (specifications) of the porous particles 40 also affects the resonance frequency; when the filled porous particles 40, When the particle size distribution is above 180 μm, a lower resonance frequency can be effectively obtained. It is worth noting that the mesh 31 of the screening element 30 has a certain relationship with the particle size of the porous particles 40. For example, when the particle size distribution of the porous particles 40 is 500 μm, the size of the meshes 31 is distributed between 300 μm and 350 μm; and when the particle size distribution of the porous particles 40 is between 180 μm and 420 μm, the meshes 31 The size is distributed from 100 μm to 350 μm as long as the size of the mesh 31 is kept smaller than the particle size of the porous particles 40.

In addition, under the same filling ratio of the filling space 122 where the porous particles 40 are located, the volume ratios of the different filling spaces 122 also acquire different resonance frequencies. When the volume ratio of the filling space 122 in the chamber 10 is excessively large, as shown in Fig. 9, the resonance frequency of the speaker single sound will be affected by the free field, and the filling of the porous particles 40 is not too obvious at this time. The benefit of reducing the resonance frequency; therefore, the filling space 122 in which the porous particles 40 are located preferably occupies 15% to 25% of the volume ratio of the entire chamber 10.

Since the speaker element provided by the present invention is particularly applied to a compact speaker, a power-saving earphone or a micro-speaker in a hand-held device, in a small mechanism space, The resonant frequency of the sound moves toward the mid-low frequency, and in the extended bandwidth range, the performance of its sound details can be fully presented. Therefore, through the above-mentioned related experiments, the present invention can virtually expand the effect of the second chamber 12 in a limited chamber structure, improve the low frequency performance of the sound, and thereby provide superior acoustic performance.

Referring to FIG. 2, a second embodiment of the speaker of the present invention, the filling space 122 of the second chamber 12 in which the porous particles 40 are located is not limited to a single configuration chamber, for example, the second in this embodiment. The filling space 122 of the chamber 12 includes a main cavity space 1221, a sub-cavity space 1222, and a bridge portion 1223 connecting the two sub-spaces 1221, 1222. The configuration of the second chamber 12 is not the subject of the present invention, but focuses on the packing ratio of the porous particles 40 in the filling space 122 in the second chamber 12, the particle size requirements of the porous particles 40 and the particles 50 themselves, and The filling space 122 occupies the volume ratio of the entire volume of the chamber 10 to achieve the technical effect of creating a virtual enlarged back cavity. Therefore, the speaker element of the present invention is not limited to the type of the microelectromechanical speaker, nor is it limited to the filling space 122 of the second chamber 12, as long as it has a chamber capable of freely vibrating the porous particles, which are all of the present invention. The concept of creation is at the same time.

In summary, the present invention can further achieve lower process efficiency and lower process/feedstock costs while maintaining superior electroacoustic properties. The present invention and its specific embodiments are not limited to the above-described examples, and the concepts may be substituted or changed by the concept and scope of the claims.

10‧‧‧ Room

11‧‧‧ first chamber

12‧‧‧Second chamber

121‧‧‧Unfilled space

122‧‧‧filled space

20‧‧‧Densor

30‧‧‧ Screening elements

40‧‧‧Porous particles

50‧‧‧ particles

Claims (21)

A speaker component includes: a chamber; a diaphragm disposed in the chamber; the chamber defines a first chamber and a second chamber by the diaphragm; a screening element is disposed in the chamber a chamber, and a filling space is defined, the filling space and the diaphragm are respectively located on opposite sides of the screening element; and a plurality of porous particles are filled in the filling space according to a filling ratio; wherein Each of the porous particles is formed by combining a plurality of porous particles. The speaker element of claim 1, wherein: the porous particles occupy more than 50% of the volume of the filling space of the second chamber. The speaker element of claim 1, wherein: the porous particles occupy the volume of the filling space of the second chamber at a filling ratio of 70% to 90%. The speaker element of claim 1, wherein: the porous particles have a particle size distribution of 1 mm or less. The speaker element of claim 4, wherein: the porous particles have a particle size distribution of from 180 μm to 420 μm . The speaker element of claim 1, wherein: the particles have a particle size distribution of 10 nm to 100 μm. The speaker element of claim 6, wherein: the porous particles have a particle size distribution of 2 μm or less. The speaker element of claim 7, wherein: the porous particles have a particle size distribution of 1 to 2 μm. The speaker element of claim 1, wherein: the particles in the single porous particle, the region distinguishes between a maximum particle and a minimum particle, and the difference in particle size between the largest particle and the smallest particle is less than 1 μm. A speaker element according to claim 1, wherein the particles are composed of a porous amorphous ceria material. The speaker element of claim 10, wherein: the amorphous ceria particles are in powder form. The speaker component of claim 1, wherein: the porous particle filling space occupies a volume ratio of the chamber of 15% to 25%. The speaker element of claim 1, wherein the porous particles are combined by an adhesive to form the porous particles, and the weight ratio of the adhesive to the porous particles is 5% to 10%. The speaker element of claim 13, wherein the adhesive is a powdery resin material or a fibrous resin material. The speaker element of claim 1, wherein: the plurality of porous particles are independent of each other and vibrate within the filling space of the second chamber. The speaker element of claim 1, wherein: the screening element is comprised of a gas permeable material. The speaker element of claim 16, wherein the gas permeable material comprises a plurality of meshes having a size smaller than a particle size of the plurality of porous particles. The speaker element of claim 17, wherein: the mesh size is distributed between 100 μm and 350 μm. The speaker element of claim 1, wherein: the porous particles have a particle size distribution of 180 μm to 420 μm, and the porous particles occupy 70% to 90% of the volume of the filling space of the second chamber, and The filling space occupies a volume ratio of the chamber of 15% to 25%. The speaker element of claim 1, wherein: the first chamber is a front sound chamber and the second chamber is a rear sound chamber. The speaker element of claim 1, wherein: the porous particles are in the form of spheres.