JP2000156899A - Damper for speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a damper suitable for reducing the thickness of a speaker, improving strength and durability by increasing the contact areas of respective intersections of respective damper materials knitted like a net and allowed to be easily manufactured and to improve weather resistance, damper performance and adhesion. SOLUTION: A band-like damper material 1 has flat laminated structure arranging a core material 1a made of polyethylene terephthalate as the center part and laminating polypropylene on the upper and lower surfaces of the core material 1a as surface layer materials 1b. These damper materials 1 are used at least for one of the warp and the weft or both the warp and weft and knitted like a net and respective intersections of the damper materials 1 are connected by heat fusion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker damper for supporting a speaker diaphragm so as to vibrate.

[0002]

2. Description of the Related Art Hitherto, a damper for a speaker has been manufactured by impregnating a woven or non-woven fabric made of various fiber materials with a phenol resin, a melamine resin, or the like, and then subjecting the impregnated material to heat molding.

[0003] In the above-mentioned production method, a resin impregnation step is indispensable, so that the production is complicated. In addition, since phenol resin is used, and this phenol resin contains formaldehyde, some people may form the resin. It has adverse effects on the human body such as dizziness, nausea and asthma, and also causes environmental pollution. For this reason, from the viewpoints of simplifying the process, preventing adverse effects on the human body and preventing environmental pollution, there has been a strong demand for a manufacturing method that does not require this impregnation process.

Japanese Patent Publication No. 57-20760 and Japanese Utility Model Publication No. 6
Japanese Patent Application Laid-Open No. 3-36793 proposes a method in which the impregnation step is omitted by utilizing heat fusion of a thermoplastic resin constituting the yarn to simplify the step, but a single resin material is used. In these productions, there was a problem that deformation and shrinkage were remarkable, and it was difficult to obtain a product having a stable shape and constant quality.

In order to solve this problem, Japanese Patent Laid-Open No.
No. 84 discloses a damper using a woven fabric of a core-sheath structure fiber made of two resin materials having different melting points. Conventionally, bonding between fibers by heat fusion of a low melting point sheath material is disclosed. The core material having a higher melting point retains its structure, thereby realizing a damper with less shrinkage and deformation.

However, the above-mentioned Japanese Patent Application Laid-Open No.
In the invention of JP-A-84, since the polyester fiber is used as the sheath material, it is necessary to set the mold temperature during molding to a relatively high temperature of 180 ° C., and it is not easy to manage the heat cycle ( The time required for one cycle becomes longer, or a heater and a cooling device with a large power are required), and further, the bending resistance and the chemical resistance required for the damper are not sufficient. there were.

[0007] From such a viewpoint, the applicant of the present invention has previously disclosed a core-sheath structure composed of two kinds of thermoplastic resins having different melting points as disclosed in Japanese Patent Application Nos. 9-29949 and 10-99450. We have proposed a speaker damper obtained by heat-forming a woven fabric.

In this damper, the intersections of the filaments are joined by self-fusion at the time of heat molding, so that complicated impregnation treatment as in the prior art is not required, and the process can be simplified and the cost can be reduced.

[0009]

From a structural point of view, this damper is, as shown in FIG. 9, a damper material 1 'having a circular cross section comprising a core 1a' and a sheath 1b 'on the outer periphery thereof. I have. In recent years, speakers have a strong tendency to be thinner, and the space in which a vibrating damper is provided is becoming narrower.

[0010] From this viewpoint, it is preferable that the thickness of the damper is also small.
As shown in FIG. 0, since the two damper materials 1 'having a circular cross section are knitted in a net shape, the thickness is increased accordingly.

Further, because of the circular cross section, the contact area at the intersection of the damper materials 1 'is a point contact, and there is a slight difficulty in durability in terms of strength.

Further, in manufacturing the damper material 1 ', since the thickness of the yarn and the ratio of the core material and the sheath material are determined by the nozzle, the degree of freedom in designing and manufacturing is low, and various performance requirements are satisfied. If it is attempted to do so, many nozzles are required, which leads to an increase in cost and a difficulty in manufacturing.

The present invention has been proposed in view of the above, and it is an object of the present invention to make the speaker thinner and increase the contact area at the intersection of the damper materials knitted in a net shape. It is an object of the present invention to provide a damper that has improved strength and durability and is easy to manufacture.

It is another object of the present invention to provide a damper having improved weather resistance.

[0015]

The present invention has a flat laminated structure in which a central portion is a core material 1a made of polyethylene terephthalate, and polypropylene is laminated on its upper and lower surfaces to form a surface material 1b. The material is used as a damper material 1, and at least one of a warp and a weft is knitted or laminated in a net shape using the damper material 1,
In addition, the above object is achieved by forming the intersections by heat fusion.

Further, a predetermined amount of a pigment component such as carbon black, carbon graphite, or titanium oxide is mixed into the polypropylene of the outer surface material 1b to achieve the above-mentioned other object.

[0017]

FIG. 1 shows a cross section of a damper body 1A used in the present invention. In the figure, 1a is a flat core material made of polyethylene terephthalate (PET), 1b is a surface material laminated and covered on the upper and lower surfaces in a flat shape,
As the material, polypropylene (PP) having a lower melting point than polyester is used, and the damper body 1A is formed in a laminated structure.

The damper material 1 can be manufactured by a simple process of cutting the damper body 1A formed as a laminated sheet or film into a strip shape, and the yarn structure is a simple laminated structure. Can be freely changed, and the thickness and width of the thread material can be easily changed. Therefore, the degree of freedom in design and manufacturing is higher than that of the prior application using the core-sheath structure shown in FIG. Has become.

FIG. 2 shows the damper body 1A shown in FIG.
The perspective view at the time of damping the damper raw material 1 cut | disconnected in the shape of an elongated strip with a rectangular cross section along the -b line | wire into a net shape and making it a base material is shown. As a specific example, the core material 1a is polyethylene terephthalate having a melting point of 260 ° C., and the surface material 1b is melting point 140.
A damper material 1 made of polypropylene at ℃ was knitted in a net shape as shown in this figure.

Then, the substrate made of the damper material 1 woven in a net shape is subjected to hot cold molding under a predetermined condition using a known molding machine.

[0021] That is, the basic molding process (1 cycle to about 4 minutes), as indicated by S ₁ in FIG. 3, the mold (not shown) heated to a predetermined temperature against the heater (145 ° C.) Let it.

Next, when the mold reaches a predetermined temperature, the heater
From the laminated filament in the mold.
Insert a damper base made of net-shaped woven cloth
One S _TwoAs shown in the figure, press (press pressure 3 kg / cm
²)I do. Press time for thin materials
It is about 30 seconds, but the temperature and time are adjusted according to the material thickness.
You.

[0023] Thereafter, as indicated by S _3, cooled by airflow the left mold of the press to a predetermined temperature (approximately 75 ° C.).

Next, a damper formed into a predetermined shape having corrugation may be taken out of the mold and used as a vibration material. FIG. 4 is a plan view of the damper D in a state where the intersections of the filaments are bonded by thermal fusion of the surface layer material 1b and formed. And this damper D
Is connected to the outer periphery of the coil bobbin of the speaker and connected to the frame, as is well known.

In the present invention produced as described above, the difference in melting point between the surface layer material 1b and the core material 1a of the base material is large, so that heat control during heat molding is easy and shape stability is further improved.

This base material is a woven fabric made of a polyolefin-based heat-sealing material using yarns having a laminated structure. Since the warp and the weft are heat-sealed, there is no misalignment or fraying. Moreover, the strength is improved because of the surface bonding, as compared with the point bonding in the case of using the conventional core-sheath structure system.

Further, since the polyolefin resin is used as a raw material, it is excellent in water resistance and environmental resistance.

As another mode of knitting in a net shape, as shown in FIG. 5, a damper material 1 having a flat laminated structure is used as a weft, and a twisted yarn such as cotton, acrylic, aramid or the like as shown in FIG. The general-purpose yarn damper material 1 ″ may be configured as a warp yarn.

As shown in FIG. 6, a warp having the same structure is arranged in a direction substantially perpendicular to a weft made of a damper material 1 having a flat laminated structure and arranged in a substantially parallel manner at an appropriate interval. A laminated structure may be provided.

FIG. 7 is a schematic front view of the damper substrate cut along, for example, oblique lines c and d in FIG.
Thus, various band-shaped damper materials can be obtained by appropriately selecting the cut portion, the width, the thickness, and the like.

FIG. 8 shows that a pigment component 1c such as carbon black, carbon graphite or titanium oxide is added to the outer layered sheath material 1b of polypropylene at 0.05% to 5.0%.
%, An example in which the weather resistance is improved by mixing in the range of%.

Conventionally, a transparent speaker diaphragm may be used. By the way, a speaker damper is required to be able to withstand aging as well as basic performance as a vibration system member. Unlike the conventional phenolic resin impregnated type, the damper according to the prior application of the applicant of the present invention uses a thermoplastic resin, so that light from the outside is damped like a speaker using a transparent diaphragm. In the case of a device directly acting on an object, or a device placed in an environment exposed to sunlight, such as an in-vehicle speaker, it is conceivable that remarkable deterioration of physical properties or damage to a structure due to light deterioration due to ultraviolet rays may occur.

For this reason, in this embodiment, the damper material 1
By mixing a pigment component 1c such as carbon into the surface material 1b at the time of manufacturing, the deterioration is prevented. The effect of lowering the mixing state within the range of 0.05% to 5.0% with respect to the laminated sheath material 1b is low at 0.05% or less, and
If it is 5.0% or more, it becomes black or white more than necessary, which is not preferable in appearance and becomes brittle.
This is because the above range does not impair the characteristics of the damper, and provides good results.

[0034]

As described above, according to the present invention, since a damper material having a flat laminated structure is used, it can be made thinner than a circular cross-section, which is suitable for making the speaker thinner. ing. In addition, the ratio of core material and surface material,
Since the width and the cross-sectional shape can be easily changed, the degree of freedom in designing and manufacturing is high, and the cost can be reduced.

Further, since the contact portion at the intersection is larger than that of the ones having a circular cross section, it is excellent in strength and durability.

Further, if a pigment component such as carbon is mixed into the sheath material, ultraviolet rays can be blocked by the pigment component in addition to the above-mentioned effects, and there is an advantage that weather resistance is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a damper body used in the present invention.

FIG. 2 is a perspective view showing a net shape of the damper material of the present invention.

FIG. 3 is an explanatory view of a manufacturing process of the present invention.

FIG. 4 is a plan view of a damper according to the present invention.

FIG. 5 is a perspective view of another example of a net-shaped damper base material of the present invention.

FIG. 6 is a perspective view of still another example of the net-shaped damper base material of the present invention.

FIG. 7 shows another example of the damper material of the present invention.

FIG. 8 shows still another example of the damper material of the present invention.

FIG. 9 is a sectional view of a conventional damper material.

FIG. 10 is a perspective view of a conventional damper base material knitted in a net shape.

[Explanation of symbols]

1A Damper body 1 Damper material 1a Core material 1b Surface material 1c Carbon black, carbon graphite,
Pigment component such as titanium oxide D Damper

Claims (2)

[Claims] A damper material having a flat laminated structure in which a central part is made of a polyethylene terephthalate core material (1a) and polypropylene is laminated on its upper and lower surfaces to form a surface material (1b). (1) Knitting or laminating a net shape on at least one or both of the warp and the weft using the damper material (1), and binding the intersections thereof by heat fusion. Speaker damper. 2. The speaker damper according to claim 1, wherein carbon black, carbon graphite or titanium oxide is mixed into the polypropylene of the outer surface material (1b).