JPH07184291A - Speaker grill - Google Patents

Abstract

PURPOSE:To simply manufacture the grill with forming operation and to obtain a product with high quality without production of reduction or deformation by integrating a synthetic resin used for the grill main body and a reinforcing rib through impregnation of a sound transmission sheet material. CONSTITUTION:A comparatively large hexagonal grating reinforcement rib 3 is formed to an entire rear face of a grill main body 1 of nearly square thin plate to which lots of punch holes 2 are made. Then the grill main body 1 and the reinforcement rib 3 are integrally formed by the same synthetic resin and a sound transmission sheet material 4 is arranged over the entire face of the grill main body 1 between the grill main body 1 and the reinforcement rib 3 and the punch holes 2 are choked by the sound transmission sheet material 4. Furthermore, the synthetic resin being a material for the grill main body 1 and the reinforcement rib 3 is set through the sound transmission sheet material 4 to integrate the grill main body 1 and the reinforcement rib 3 altogether.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker grill for covering the surface of an audio speaker or other various speakers mounted in an automobile, and more specifically, it will be described in detail in a cover body having a large number of small holes. The present invention relates to a speaker grill in which holes are closed with a sound-permeable sheet material to prevent dust and dirt from entering.

[0002]

2. Description of the Related Art Conventionally, a large number of punchings have been performed as a speaker grill for covering a surface of an audio speaker or other various speakers mounted in an automobile to protect a speaker cone. A sound-permeable sheet material such as a woven cloth, a non-woven cloth, or a knitted cloth is arranged on the back surface side of a substrate having a large number of small holes such as a substrate provided with holes or a lattice-like substrate to close the small holes of the substrate, It is known that the entry of dust and dirt is prevented.

Conventionally, a conventional speaker grill has a sound-transmitting sheet material fixed to a substrate by the following method. 1. A method in which a sound-transmitting sheet material is arranged on the back side of a substrate made of synthetic resin, and the resin is welded to the substrate at a plurality of places. 2. A method of arranging a sound-transmitting sheet material on the back side of a substrate, fixing a frame-shaped or lattice-shaped pressing member to the back side of the substrate, and sandwiching and fixing the sound-transmitting sheet material between the pressing member and the substrate.

However, in the case where the sound-transmitting sheet material is attached to the substrate by the above resin welding, the step of molding the substrate, the step of disposing the sound-transmitting sheet material on the back surface of the obtained substrate, and the resin welding at a plurality of places A large number of steps are required, and performing resin welding at a plurality of places requires considerable labor and cost. Further, in the case where the sound-transmitting sheet material is sandwiched and fixed between the pressing body and the back surface of the substrate, two molded parts of the substrate and the pressing body are required, and after the sound-transmitting sheet is arranged on the back surface of the substrate. However, an assembling step for assembling the pressing body to the substrate is required, which makes automation difficult and is disadvantageous in cost. Further, there is a problem that the sound-transmitting sheet material provided on the back surface of the substrate is apt to be displaced or shifted.

On the other hand, when molding the substrate with synthetic resin, the sound-permeable sheet material is placed in the center of the mold, and the molding resin is injected into the mold from one side of the sound-permeable sheet material. A method is also proposed in which the resin is passed through the sound-transmitting sheet material and is advanced to the opposite side of the sheet material to obtain a substrate in which the sound-transmitting sheet material is integrated in the middle portion in the thickness direction of the substrate. ing. (JP-A-63-37800, U.S. Pat. No. 4,832,150).

According to this method, a speaker grill having a sound-transmitting sheet material attached thereto by a molding operation can be obtained without requiring an assembling step or a step of attaching the sound-transmitting sheet material. In the case of obtaining a speaker grill in which a conductive sheet material is arranged and integrated, the above-mentioned sound-transmitting sheet material becomes a large resistance at the time of resin injection and the flow of the molding resin becomes insufficient, resulting in a fine grid plate or fine punch holes. The substrate with may not be molded well,
There is a problem that sink marks and distortions are likely to occur on the obtained substrate.

The present invention has been made in view of the above circumstances, and can be easily manufactured by a molding operation without requiring an assembly step, a step of attaching a sound-transmitting sheet material, and the like, and moreover, a punch hole and a grid can be formed. An object of the present invention is to provide a speaker grill that can surely obtain a high quality product without causing sink marks or distortion even if it is made extremely fine.

[0008]

In order to achieve the above object, the present invention uses a synthetic resin to provide a lattice-like reinforcing rib larger than the grill main body on the back surface of a thin plate-shaped grill main body made of synthetic resin having a large number of small holes. A sound-permeable sheet material is provided along the surface direction between the grill main body and the reinforcing ribs, and a synthetic resin forming the grill main body and a synthetic resin forming the reinforcing ribs are provided integrally. Provided is a speaker grill, wherein the sound-permeable sheet material is permeated and penetrated to be integrated with each other.

[0009]

The structure of the speaker grill of the present invention is as described above, and in the case of obtaining this speaker grill, the grill main body having a plate-shaped cavity having fine punch holes and lattice holes is formed. And a half mold for molding the above-mentioned reinforcing ribs having large lattice-shaped cavities, and a sound-transmitting sheet material such as woven cloth, non-woven cloth, and knit cloth is arranged between both cavities. Then, by injecting a resin from the mold half side for molding the reinforcing rib, this resin is transmitted through the sound-permeable sheet material,
It is manufactured by filling resin into the cavities of both mold halves and molding.

In this case, according to the speaker grill of the present invention, since the cavity of the reinforcing rib side mold into which the resin is injected has a large lattice shape, the resin has good fluidity and the corners inside the cavity are good. The resin can be spread all over the place and molding can be done neatly without sink marks or distortion. In particular, in the present invention, since the sound-transmitting sheet material is arranged between the mold halves, there is considerable resistance for the resin to permeate the sound-transmitting sheet material, and therefore the fluidity of the resin should be ensured. Greatly affects the moldability.

That is, when the sound-transmitting sheet material is arranged in the middle portion in the thickness direction of the substrate having fine punch holes or lattice holes as in the conventional case, when the resin is injected from one of the molds, Before passing through the sound-permeable sheet, it has to pass through a lattice plate-shaped cavity with fine punch holes or lattice holes with large flow resistance, and therefore sufficient pressure cannot be obtained when passing through the resin. The resin cannot flow sufficiently in the cavity on the opposite side, and sink marks and distortion are likely to occur. On the other hand, in the speaker grill of the present invention, the cavities on the side where the resin is injected are formed in a relatively large lattice shape, and the resin can flow relatively well in the cavity,
Moreover, since it is in a state where it partially communicates with the lattice plate-shaped cavity on the opposite side (in the past, since the front side cavity and the back side cavity have the same shape, they communicate with each other over the entire surface), a sound-transmitting sheet The pressure of the resin that penetrates the material is partially concentrated, and the resin penetrates the sound-permeable sheet material well and flows in the cavity on the opposite side.

Therefore, the speaker grill of the present invention has a good appearance with a large number of fine punch holes and lattice holes formed on the surface thereof, and the rigidity of the entire grill is increased by the reinforcing ribs formed on the back surface. Excellent in that it can effectively prevent the occurrence of cracks and the like, and the above-mentioned sound-transmitting sheet material is in a state of being partially integrated with the resin forming the front surface and the back surface. Therefore, no deviation or deviation occurs. Further, such an excellent speaker grill can be easily manufactured by a molding operation without requiring an assembly process, a sound-permeable sheet material mounting process, and the like.

Further, since the back side of the speaker grill of the present invention has a comparatively large lattice shape, the back side is a half mold cavity forming the back side as compared with the case where a back side having the same shape as the front side is obtained. Since the shape is simple, maintenance of the mold is easy, and the mold release property after molding is good. In addition, the speaker grill of the present invention has good rigidity due to the reinforcing ribs on the back surface side as described above, but in this case, since the reinforcing ribs have a relatively large lattice shape, the front and back surfaces are the same. The amount of resin used can be significantly reduced as compared with the case where a shaped product is formed to a thickness sufficient to obtain similar rigidity.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a speaker grill according to an embodiment of the present invention, in which 1 is a large number of punch holes 2
2 is a substantially rectangular thin plate-shaped grill body that has been pierced, and as shown in FIG. 2, reinforcing ribs 3 are formed in a relatively large hexagonal lattice shape on the entire back surface thereof. The grill body 1 and the reinforcing ribs 3 are integrally molded of the same synthetic resin.

Between the grill body 1 and the reinforcing ribs 3, as shown in FIG. 3, a sound-permeable sheet material 4 is provided.
Are arranged over the entire surface of the grill body 1, and the punch holes 2 are closed by the sound-permeable sheet material 4. Further, the synthetic resin forming the grill main body 1 and the reinforcing ribs 3 penetrates the sound-permeable sheet material 4 and is integrated with each other, whereby the sound-permeable sheet material 4 is integrated into the grill main body 1 and It is integrated with the reinforcing rib 3.

The grill main body 1 is attached to the inner peripheral surface of a substantially square ring-shaped frame body 5 to form a speaker grill. That is, the fitting protrusions 6 are provided on the four corners and the middle part of the short side of the grill body 1.
Are abutted against each other.
The grill main body 1 is attached to the frame body 5 by being fitted and fixed to the tubular fitting cylinder 8 provided on the flange portion 7 formed on the inner peripheral surface of the speaker body, thereby forming a speaker grill.

The sound-transmitting sheet material 4 is not particularly limited, but may be woven cloth, non-woven cloth, knitted cloth, etc., and non-woven cloth is particularly preferably used. In this case, as the non-woven fabric, a fabric having a basis weight (weight per 1 m ² ) of about ²⁰ to 120 g / m ² can be used, but if the basis weight is too large, the resin may not be able to permeate well during the molding described later. Also, the sound transmission may be lowered and the sound quality of the speaker may be deteriorated.
On the other hand, if the basis weight is too small, it may not be possible to reliably collect dust and dirt. Usually, a material having a weight of about 40 g / m ² is preferably used. The thickness of the sound-transmitting sheet material 4 is appropriately selected according to its material and the like, and is not particularly limited, but in general, the thinner, the better, and in the case of a non-woven fabric, 0.2 mm or less. Is preferably used.

The resin material for molding the grill main body 1 and the reinforcing ribs 3 may be any material as long as it is injection moldable and has excellent fluidity at the time of injection. A crystalline resin such as polyacetal or polypropylene is preferably used.

In this speaker grill, a half mold for molding the grill body 1 and a half mold for molding the reinforcing ribs 3 are combined, and the sound transmissive sheet material 4 is provided between both cavities. By arranging and injecting the resin from the side of the mold for molding the reinforcing ribs 3, the resin is transmitted through the sound-transmitting sheet material 4, and the cavity is filled with the resin for molding. It is manufactured by

In this case, according to the speaker grill of this embodiment, since the cavity of the reinforcing rib 3 side mold into which the resin is injected has a relatively large hexagonal lattice shape, the resin has good fluidity, The resin can be reliably spread to every corner of the cavity, and molding can be performed neatly without sink marks or distortion.

That is, when the back side of the grill has the same shape with the fine punch holes as the front side as in the conventional case, when the resin is injected from one of the molds, the resin is the sound transmissive sheet material 4. Prior to permeation, it must pass through a substrate-like cavity with fine punches that have high flow resistance. Therefore, when passing through the sound-transmitting sheet material, sufficient pressure cannot be obtained, the resin cannot sufficiently flow in the cavity on the opposite side, and sink marks and distortion are likely to occur. On the contrary,
In the speaker grill of this embodiment, the cavities on the side where the resin is injected are formed in a relatively large hexagonal lattice, and the resin can flow relatively well in the cavity,
Moreover, since it is in a state of partial communication with the plate-shaped cavity on the opposite side (conventionally, the front surface side cavity and the rear surface side cavity have the same shape, so they are in full communication), so a sound-transmitting sheet material The pressure of the resin passing through 4 is partially concentrated, and the resin penetrates the sound-permeable sheet material 4 well and flows in the cavity on the opposite side. Moreover,
In the grill of this embodiment, since the small holes 2 formed in the grill body 1 are circular punch holes, the resin can be easily circumvented, and also from this point, the occurrence of sink marks can be effectively prevented.

Therefore, the speaker grill of this embodiment is
The surface thereof has an appearance that is excellent in design with a large number of fine punched holes 2 formed, and the reinforcing ribs 3 formed on the back surface provide excellent rigidity of the entire grill and effectively prevent the occurrence of cracks and the like. Further, since the resin forming the grill main body 1 and the reinforcing ribs 3 permeates the sound transmissive sheet material 4 to be in a state of being partially integrated with the resin, deviation or deviation occurs. Never. Further, such an excellent speaker grill can be easily manufactured by a molding operation without requiring an assembly process, a sound-permeable sheet material mounting process, and the like.

Further, since the rear surface of the speaker grill of this embodiment has a relatively large grid-shaped portion 3, the rear surface is formed in a half shape as compared with the case where the same shape as the front surface is obtained. Since the mold cavity shape is simple, maintenance of the mold is easy and the mold release property after molding is good. In addition, the speaker grill of the present embodiment has good rigidity due to the reinforcing ribs 3 on the back surface side as described above, but in this case, since the reinforcing ribs 3 have a relatively large grid shape, It is possible to greatly reduce the amount of resin used, as compared with the case where the both surfaces have the same shape and are formed to have a thickness sufficient to obtain similar rigidity.

The speaker grill of the present invention is not limited to the above embodiment, and various modifications may be made without departing from the gist of the present invention. For example, the shape of the small holes 2 of the grill main body 1 is preferably a circular punch hole because the resin can be easily rotated, but the shape is not limited to this, and it may be an oblique lattice or a cross lattice. . Further, the shape of the reinforcing ribs 3 is not limited to the hexagonal lattice shape, and various shapes such as an oblique lattice, a cross lattice, a vertical lattice, a horizontal lattice, and a circular lattice can be formed. Although it is configured to be fitted and fixed to the ring-shaped frame body 5, the frame 5 may be integrally formed with the grill body 1. Furthermore, other configurations may be variously modified without departing from the gist of the present invention.

[0025]

As described above, according to the speaker grill of the present invention, it is possible to easily manufacture the speaker grill by a molding operation without requiring an assembling process, a mounting process of the sound-transmitting sheet material, and the like. Even if the holes and the grid are made very fine, it is possible to reliably obtain a high-quality product without causing sink marks or distortion.

[Brief description of drawings]

FIG. 1 is a plan view with a partially enlarged view showing a speaker grill according to an embodiment of the present invention.

FIG. 2 is a rear view showing a partially enlarged view of the speaker grill.

FIG. 3 is a partially enlarged sectional view showing the speaker grill.

[Explanation of symbols]

 1 Grill Main Body 2 Punch Holes (Small Holes) 3 Reinforcing Ribs 4 Sound Transmission Sheet Material 5 Frame Body 6 Fitting Protrusion 7 Flange 8 Fitting Tube

Claims (1)

[Claims] 1. A lattice-like reinforcing rib larger than the grill main body is integrally provided with the synthetic resin on the back surface of a synthetic resin thin plate grill main body having a large number of small holes, and between the grill main body and the reinforcing rib. A sound-permeable sheet material is arranged along the surface direction, and the synthetic resin forming the grill body and the synthetic resin forming the reinforcing ribs are penetrated through the sound-permeable sheet material and integrated with each other. The speaker grill that is characterized.