JPS62286400A - Supporting member for electroacoustic transducer diaphragm - Google Patents

Abstract

PURPOSE:To obtain an electroacoustic transducer to which a diaphragm is ideally supported, which has an excellent frequency characteristic and less secular change by constituting a supporting member with a polyvinyl chloride thermoplastic elastomer including a molecule constraining constituent made of crystal polyvynile chloride and a rubber constituent made of non-crystal polyvynile chloride. CONSTITUTION:The polyvinil chloride thermoplastic elastomer including a molecule constraining constituent made of crystal polyvynile chloride and a rubber constituent made of non-crystal polyvynile chloride is formed into a sheet of a thickness of 0.3mm by means of extrusion molding, and further molded into the edge of a shape shown in the figure by means of vacuum molding. A speaker produced by using this edge is excellent in its linearity of characteristic, and the difference reciprocating deviation of its diaphragm, i.e., the hysteresis is extremely small, which are advantages. Also, higher frequency resonance peaks are released, and more flat frequency characteristic can be obtained. As for its light-resistance (measured with a carbon weather meter), the performance shows almost no degrading after 500 hours of irradiation, thus, the degrading of the frequency characteristic due to the secular change is reduced.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] This invention relates to improvements in support members such as edges and dampers for elastically supporting a diaphragm for an electroacoustic transducer.

``Prior Art'' This type of support member, for example, the edge for the speaker 1 sliding plate, is explained as follows: ① A cotton cloth or the like is impregnated with a thermosetting resin, and then coated with a viscoelastic material such as rubber. Coated cloth edge heated and formed into a predetermined edge shape 2. Foamed urethane edge formed by heat formed from foamed urethane 1 to a predetermined edge shape has been widely used.

[Problem to be Solved by the Invention 1] However, the conventional edge described above has various unsatisfactory points. In addition, the amount of coating of the viscoelastic material is limited due to the weight increase due to the coating layer, so it is practically impossible to obtain sufficient internal loss, resulting in poor braking action for high-frequency co-photography, and flat frequency characteristics are not obtained. It has problems that are difficult to deal with.

In addition, although the edge (■) has better elasticity than the edge (2), it has the same problem as the edge (■) because the internal loss is not sufficient, and it also has poor light resistance and its physical properties are affected by light, especially ultraviolet rays. There was a problem with significant deterioration.

[Means for Solving the Problem 1] The present invention uses a polyvinyl chloride thermoplastic elastomer containing a molecular restraint component made of crystalline polyvinyl chloride and a rubber component made of amorphous polyvinyl chloride as a supporting member of a diaphragm for an electroacoustic transducer. It is composed of

[Function] The support member can ideally support the diaphragm because of its good elasticity, sufficient internal loss, and good light resistance and heat resistance, and it has good frequency characteristics and is durable over time. We were able to provide an electroacoustic transducer with little change.

[Example] Hereinafter, this invention will be explained with reference to examples.

A polyvinyl chloride thermoplastic elastomer containing a molecular restraint component made of crystalline polyvinyl chloride and a rubber component made of amorphous polyvinyl chloride was formed into a sheet with a thickness of 0.3# by extrusion molding, and the sheet was further molded into a sheet with a thickness of 0.3 #. It was vacuum formed into an edge of the shape shown in the figure.

Then, a speaker 1 was manufactured using the edge.

On the other hand, as a comparative example, a speaker 2.3 was obtained using a coated fabric edge (real cotton fabric #2210 coated with SBR latex) and a foamed urethane edge (8# thick) having the shape shown in FIG.

[Effects of the Invention] The input-displacement characteristics and frequency characteristics of the speaker 1 of the present invention and the comparative speaker 2.3 are shown in FIGS. 1a and 1.
Shown in Figure b and Figure 2.

As can be seen from FIGS. 1a and 1b, this embodiment of the invention has the advantage of extremely good linearity and extremely small difference in reciprocating displacement of the diaphragm, that is, hysteresis.

Furthermore, as can be seen from FIG. 2, according to the embodiment of the present invention, the peak of high frequency coexistence is relaxed, and a flatter frequency characteristic can be obtained.

This shows that the edge braking action of this embodiment of the invention is good.

Furthermore, the light resistance (according to carbon weather meter) is 500
After time irradiation, the tensile strength of the foamed urethane edge decreased by about 20%, whereas the edge of the example of this invention showed almost no change and its light resistance was improved, thereby reducing the deterioration of properties due to aging. .

Further, according to the embodiment of the present invention, the change in Young's modulus due to temperature change is extremely small compared to the conventional edge, and in particular, the change in characteristics due to temperature is almost negligible in the normal operating temperature range of the speaker.

[Brief explanation of drawings]

FIG. 1a is an input-displacement characteristic diagram of a speaker using an edge according to an embodiment of the present invention, FIG. 1b is an input-displacement characteristic diagram of a speaker using a conventional edge, and FIG. FIG. 3 is a diagram showing the shape of the example edge and the conventional edge.

Claims (1)

[Claims] In a support member that elastically supports a diaphragm for an electroacoustic transducer, the support member is composed of a polyvinyl chloride thermoplastic elastomer containing a molecular constraint component made of crystalline polyvinyl chloride and a rubber component made of amorphous polyvinyl chloride. A support member for a diaphragm for an electroacoustic transducer, characterized by: