JPS628077B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to non-vibration components of a speaker that are attached directly or indirectly to a cabinet, such as a speaker frame, horn, equalizer, acoustic lens, and grill. The frame is fixed to the magnetic circuit and supports the opening side of the diaphragm, and is also used to attach the speaker to the cabinet, so the desired characteristics of the frame are high rigidity, large internal loss, and vibration of the diaphragm. It is also difficult to resonate with Similarly, desirable characteristics of a speaker horn are high rigidity, high internal loss, and low resonant frequency.
Furthermore, characteristics such as high rigidity and high internal loss are essential even for non-vibrating components of speakers such as acoustic lenses, equalizers, and grills. Focusing on this, the present inventors have proposed Japanese Patent Application Nos. 54-135099 (Speaker Frame) and 1982-135097 regarding non-vibrating parts for speakers using materials that replace conventional metals and plastics. (Acoustic Lens), Patent Application No. 135098 (Sho 54-135098) (Equalizer),
We filed Japanese Patent Application No. 135095/1983 (speaker horn) and demonstrated the excellent features of these non-vibrating components for speakers. However, non-vibrating components of speakers made of these materials have problems with temperature resistance, and there is a risk of deformation in places such as car stereos where indoor temperatures may be high. The present invention has been made in view of such conventional problems, and has the features of high rigidity, high internal loss, and high temperature resistance, and is particularly suitable for the construction of car stereo speakers. The purpose is to provide system parts. The invention will be explained in detail below. The present invention is characterized by post-chlorinated vinyl chloride alone, or a mixture of post-chlorinated vinyl chloride and polymethyl methacrylate, and if necessary, adding nitrile butadiene rubber (NBR) or butyl rubber (IIR) to these synthetic resins. , a non-vibrating component of a speaker made of a mixture of a mixed material containing a rubber material such as styrene-butadiene rubber (SBR) and flaky graphite powder. Further, the present invention is characterized by a non-vibrating component for a speaker, which is formed from the above-mentioned kneaded material and further includes flaky graphite powder oriented along the surface. When discussing heat resistance at the temperature at which the elastic modulus is halved, post-chlorinated vinyl chloride has a heat resistance that is 10 to 20°C higher than that of vinyl chloride resin, and polymethyl methacrylate (PMMA) has a heat resistance that is 10°C higher than that of vinyl chloride resin. It's nearby and expensive. Therefore, these synthetic resins have better heat resistance than molding materials based on vinyl chloride resins. Rubber-based materials contribute to improving internal loss due to their softness. The flaky graphite powder contributes to an improvement in the elastic modulus that cannot be expected from a resin alone, and especially when its orientation is aligned in one direction, the elastic modulus is significantly improved. The flaky graphite powder preferably has an average particle size of about 20 μm or less, particularly 5 μm or less. In addition, if the blending ratio of graphite powder and resin is in the range of 10 to 90 wt% graphite powder and 90 to 10 wt% resin, it is expected that the graphite powder will improve the elastic modulus, and it will not impair moldability. It hardly causes any embrittlement, especially when graphite powder is 50~75wt% and resin is 50~75wt%.
At 25 wt%, the properties are significantly improved.
PMMA is widely used as a processing aid for post-chlorinated vinyl chloride, but the blending ratio of the two can be arbitrarily determined and can be changed depending on the shape and properties of the intended molded product. The rubber material is added as needed in the range of 2 to 50 wt% to the resin, and if it is added about 10 wt%, the elastic modulus E will be about 20.
% decrease, but the internal loss tan〓 is improved by about 1.5 to 2 times. When manufacturing non-vibrating parts for speakers,
First, a resin material of post-chlorinated vinyl chloride alone or a mixed resin material of post-chlorinated vinyl chloride and polymethyl methacrylate, and if necessary, a resin material 1 in which a rubber-based material is added thereto, and flaky graphite powder 2 are mixed,
Furthermore, if necessary, plasticizers and stabilizers are added and mixed, and the mixture is heated at 130 to 180°C, the softening and melting temperature of the resin material, as shown in Figure 1 using an appropriate kneading device such as a kneader or roll. Knead while stirring. This kneaded material 3 can be compression molded, injection molded,
It is used for molding non-vibrating parts of speakers such as speaker frames, horns, acoustic lenses, equalizers, grills, etc. by appropriate molding methods such as press molding. For example, taking compression molding as an example, as shown in Figure 2, material 3 is put into a mold 4 corresponding to the shape of the non-vibrating component of the intended speaker, and then mold 5 is fitted with mold 4. The material 3 is made to flow into every corner of the molds 4 and 5 by applying pressure under heat, and then the molds 4 and 5 are cooled down. Next, the molds 4 and 5 are opened and the molded product is poured out from inside. 6 is taken out. Figure 3 a-d
are a speaker frame 7, a horn 8, an acoustic lens 9, and an equalizer 1 molded by the above method, respectively.
0, grill 11 is shown. Incidentally, the acoustic lens 9 is 1
A single plate material 90 is formed and assembled using the method described above. Since the graphite powder 2 is not oriented in one direction in the resin material 1, the kneaded material 3 has an elastic modulus E that is 1/2 to 1/3 of that in the case where it is oriented, and is inferior in rigidity, but has a high internal It has the same loss, is less likely to cause resonance, and has sufficient damping characteristics against vibrations, so it can be used for molding non-vibrating components of speakers. The kneaded material 3 is rolled many times with rolls to improve its elastic modulus and is formed into a sheet as shown in FIG. 4. By forming the graphite powder into a sheet by roll rolling, the graphite powder 2 is oriented along the band surface of the sheet material 12, and its elastic modulus is increased to 2 to 3 times that of the unoriented one. This sheet material 12 may be formed by a single sheet or by stacking an appropriate number of sheets as shown in FIG. 5 as required, and then heated and formed by a forming method such as vacuum forming, pressure forming, press forming, etc. as shown in FIGS. 3 a to 3 d. It is molded into a non-vibrating part of a desired speaker such as In other words, if the non-vibrating component of the speaker is thick, it can be obtained by a press molding method in which the sheet materials 12 are stacked until the required thickness is achieved, and then placed in a lower mold and pressed by an upper mold to apply pressure. . In the non-vibrating parts of each speaker obtained by this molding, graphite powder is oriented along the surface, resulting in stiffness and
The elastic modulus becomes a large value. The present invention will now be described in detail based on Examples. [Example 1] Post-chlorinated vinyl chloride 100 parts by weight Flake graphite powder 200 〃 Lead stearate (stabilizer) 5 〃 DOP (plasticizer) 10 〃 [Example 2] Post-chlorinated vinyl chloride 100 parts by weight Polymethyl Methacrylate 5 〃 Scale graphite powder 150 〃 Lead stearate 2 〃 DOP 10 〃 [Example 3] Post-chlorinated vinyl chloride 100 parts by weight IIR 10 〃 Scale graphite powder 200 parts by weight Lead stearate 5 〃 DOP 10 〃 [Implementation] Example 4 Post-chlorinated vinyl chloride 100 parts by weight polymethyl methacrylate 5 IIR 10 150 〃 Lead stearate 2 DOP 10 〃 [Comparative example] Vinyl chloride resin 100 parts by weight scaly graphite powder 200 〃 Stearin Acid lead 5 〃 DOP 10 〃 Each powder is heated in a kneader at 150 to 160℃ with the above blending ratio.
The mixture was kneaded under heating to obtain a kneaded product. In addition, in order to obtain orientation of graphite, the above-mentioned kneaded material was passed through a roller to obtain a sheet material. The physical properties of these materials are shown below.

【table】

[Table] Next, various non-vibrating parts of speakers were molded using the materials of the above examples. That is, using the materials of each example, a speaker frame, a horn, an equalizer, an acoustic lens, and a grill were manufactured by compression molding and press molding for cases in which the graphite powder was unoriented and cases in which the graphite powder was oriented. The non-vibrating parts of each speaker obtained above have a material composition mainly composed of synthetic resin and graphite powder, so they have a low density and are lightweight. In the case of the one with added material, it was larger due to its softness. Furthermore, oriented graphite powder has elasticity,
It has high rigidity, and therefore each part can be formed with high internal loss while maintaining strength. Furthermore, when we measured the heat resistance of each of the above parts, we found that they did not deform even when heated to approximately 12°C.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the kneaded material used for molding the non-vibrating parts of the speaker of the present invention, Fig. 2 is a process diagram showing an example of molding the non-vibrating parts of the speaker of the present invention, and Figs. 3 a and b. , c, d, and e are perspective views of a speaker frame, a horn, an acoustic lens, an equalizer, and a grill, respectively, according to an embodiment of the present invention. FIG. 5 is a cross-sectional view of the oriented sheet materials, and a perspective view of the sheet materials stacked together. 1...Resin material, 2...Scary graphite powder, 3...
... Kneading material, 7 ... Frame, 8 ... Horn, 9
...Acoustic lens, 10...Equalizer, 11...
Grill, 12...Sheet material.

Claims (1)

[Claims] 1. A non-vibrating component for a speaker made of a kneaded material whose main components are post-chlorinated vinyl chloride and flaky graphite powder. 2. A non-vibrating component for a speaker, characterized in that it is formed from a kneaded material containing post-chlorinated vinyl chloride and flaky graphite powder as main components, and the flaky graphite powder is oriented along the surface. 3. A non-vibrating component for a speaker made of a kneaded material whose main components are post-chlorinated vinyl chloride, polymethyl methacrylate, and flaky graphite powder. 4. A non-vibration system for a speaker formed of a kneaded material mainly composed of post-chlorinated vinyl chloride, polymethyl methacrylate, and flaky graphite powder, and characterized in that the flaky graphite powder is oriented along the surface. parts. 5. A non-vibrating component for a speaker made of a kneaded material whose main components are post-chlorinated vinyl chloride and flaky graphite powder, which is a rubber-based material. 6. A non-vibration system for a speaker formed of a kneaded material mainly composed of post-chlorinated vinyl chloride, a rubber-based material, and flaky graphite powder, and characterized in that the flaky graphite powder is oriented along the surface. parts. 7. A non-vibrating component for a speaker made of a kneaded material whose main components are post-chlorinated vinyl chloride, polymethyl methacrylate, a rubber material, and flaky graphite powder. 8. A speaker formed of a kneaded material mainly composed of post-chlorinated vinyl chloride, polymethyl methacrylate, and flaky graphite powder of a rubber-based material, and characterized in that the flaky graphite powder is oriented along the surface. non-vibrating parts.