JP3069859B1 - Method of manufacturing exterior case of light emitting display, and outer case of light emitting display - Google Patents

Abstract

A segment housing (11) for housing a light-emitting segment has a case main body (1) made of a resin material of high brightness color.
0) penetrates the ceiling wall (91) from front to back, and the ceiling wall (91)
The method for manufacturing an outer case of a light-emitting display device in which a dark layer (15) overlaps around the segment receiving hole (11) on the surface of
The surface of the dark layer (15) can be easily prevented from sticking to the inner peripheral wall of (11) and spreading, and even if the surface of the case main body (10) is wavy due to sink during resin molding. Prevents ripples and reduces the occurrence of defective products. SOLUTION: The dark layer is provided on the surface of the case main body (10).
(15) is injection molded with a resin material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an outer case of a light-emitting display device for lighting a light-emitting segment such as a light-emitting diode. For example, the present invention relates to a method of manufacturing seven light-emitting diode-type segments arranged in a figure eight shape. The present invention can be applied to a case of manufacturing an outer case of a provided 7-segment type or 8-segment type numeric display.

[0002]

2. Description of the Related Art FIG. 4 shows an LED as an example of a light emitting display.
It is a perspective view of a notch of a conventional exterior case of a type number display. The exterior case (1) includes a case body (10) formed of a resin of a high-brightness color such as white (a color having a high light reflectance) and having a cavity (12) opened downward, and a case body (10). It is composed of a dark color layer (15) having a low brightness color (a color having a low light reflectance) on the surface of (10).

On the surface of the ceiling wall (91) of the case main body (10), seven segment receiving holes (11) (1)
1) is open. In addition, the segment accommodation holes (11) (11)
Is formed with a decimal point segment receiving hole (13) for mounting a light emitting diode for displaying a decimal point. Molding the case body (10) with resin of high brightness color
The segment accommodation holes (11) (1) for light from the light emitting segments (21) (21) accommodated in the segment accommodation holes (11) (13)
The reason is to increase the reflectance of the peripheral wall in 3) so that high-luminance display can be secured.

[0004] On the other hand, a dark layer (15) coated with black paint is formed on the surface of the ceiling wall (91) of the case body (10), whereby the segment accommodating holes (11) and (11) are formed. The brightness difference between the brightness of the opening and the brightness of the surrounding background is increased to enable a display with clear contrast. It is empirically known that the appropriate value of the thickness of the dark-colored layer (15) is up to about 1 mm. ) Is excessively absorbed by the thickness of the dark layer (15) from the periphery.

[0005]

However, when the paint is applied to the surface of the ceiling wall (91) of the case body (10) to form the dark layer (15) as in the above-mentioned conventional case, the case body (10) 1
The undried paint applied to the surface of (0) is
(11) It drips down along the peripheral wall of (11), and a liquid dripping portion (16) is generated, whereby a defective product is easily generated.

[0006] The case is mainly formed by sinking during resin molding.
When the surface of (10) is wavy, even if a coating material for the dark-colored layer (15) is applied thereto, the surface does not become flat and the appearance is not improved. Therefore, defective products are liable to occur for such reasons.

[0007] The present invention has been made in view of the above points,
`` Segment accommodation hole (11) for accommodating light-emitting segments
However, it penetrates through the ceiling wall (91) of the case main body (10) made of a high brightness color resin material from the front to the back, and around the segment accommodation hole (11) on the surface of the ceiling wall (91). Is the dark layer (15)
Method of manufacturing an outer case of a light emitting display with overlapping
In this case, the material of the dark layer (15) can be easily prevented from adhering to the inner peripheral wall of the segment receiving hole (11) and spreading, and the surface of the case main body (10) can be wavy due to sink during resin molding. It is an object of the present invention to prevent the surface of the dark layer (15) from waving even when it is struck, thereby reducing the occurrence of defective products. <1> A technical means of the present invention for solving the above-mentioned problem is that "the dark layer (15) is injection-molded with a resin material on the surface of the ceiling wall (91)".

According to the above technical means, the case body (10)
Since the dark layer (15) on the surface of the ceiling wall (91) is molded from a resin material, when manufacturing the outer case (1), the case body (1) is used.
A dark layer is formed on the inner peripheral wall of the segment accommodation hole (11) formed in (0).
There is no worry that the material of (15) will hang down and spread as it travels.

Further, since the dark layer (15) is resin-molded on the surface of the ceiling wall (91) of the case main body (10), even when the surface of the case main body (10) is wavy, the above-described coating is applied. Dark layer (1
5) The worries of the surface are reduced.

[0010]

The present invention has the following specific effects. When manufacturing the outer case (1), there is no fear that the material of the dark layer (15) will hang down and spread over the inner peripheral wall of the segment accommodating hole (11) formed in the case main body (10), and Even if the surface of the case main body (10) is wavy, the surface of the outer case (1) can be less wavy by molding the dark layer (15) with resin, thereby reducing the occurrence of defective products. Can be.

Further, since the dark color layer (15) is formed by resin molding, the bonding strength of the dark color layer (15) to the case main body (10) is increased as compared with the conventional case where the dark color layer (15) is formed by paint. The layer (15) becomes difficult to peel off.

Further, in the above-described conventional device, if the paint for the dark-colored layer (15), in particular, the paint in an undried state dries until the paint is hit by an obstacle before the paint is dried, The fabric of the case main body (10) is exposed to the scar. On the other hand, according to the above-mentioned technical means, the dark layer (15) is already hardened at the completion of molding and has a predetermined surface hardness, so that the problem of the above-mentioned damage due to collision of an obstacle is reduced.

In the prior art described above, if the surface of the case main body (10) is wavy due to sink during resin molding, the paint cannot be applied to the entire surface and the surface of the case main body (11) is exposed. There are cases. That is, the dark layer (15) may be partially missing. In contrast, in the present invention, the dark layer (15)
Injection molding, the case main body by the above sink (10)
Even if the surface is wavy, the dark layer (15) can be formed on the entire surface, and there is no fear that a missing portion of the dark layer (15) occurs. <Item 2> In the above item 1, the method for injection-molding the dark layer (15) with a resin material on the surface of the ceiling wall (91) conforms to the peripheral wall shape of the segment accommodation hole (11). A male mold having an outer peripheral projection and molding the back surface of the case body (10), a primary molding female mold for molding the surface shape of the case body (10), and the dark layer (15) Prepare a female mold for secondary molding to mold the surface shape of, form the resin of high brightness color in the molding space surrounded by the male mold and the female mold for primary molding to form the case main body (10) A first forming step of forming;
After the molding step, a mold opening step of separating the female mold for primary molding from the male mold with the case main body (10) remaining in the male mold, and after the mold opening step, the male mold and the second mold are separated. And a second molding step of forming a dark-colored layer (15) by forming a low-brightness color resin in the secondary molding female mold by matching the secondary molding female mold. " Can be.

In this apparatus, a resin of a high brightness color such as white is formed in a molding space surrounded by a male mold for molding the back side shape of the segment accommodating hole (11) and a female mold for primary molding. When the forming step is performed, the case main body (10) is formed by these two dies. Next, a mold opening step of separating the female mold for primary molding from the male mold is performed with the case main body (10) remaining on the male mold side. When the case main body (10) remains on the male side, the corresponding male convex portion is densely inserted into the segment accommodation hole (11) of the case main body (10). ing. Next, in place of the female mold for primary molding, a female mold for secondary molding is matched with the male mold, and a resin of low lightness color for the dark layer (15) is placed in the female mold for secondary molding. Shape. Then
At this time, since the corresponding male protrusion is densely inserted into the segment accommodation hole (11),
There is no concern that the low-brightness color resin will enter the segment receiving hole (11). That is, there is no inconvenience that the resin of the low brightness color drips on the peripheral wall in the segment accommodation hole (11).

<Item 3> In the above item 1 or 2, it is assumed that “the segment wall (11) is formed in the ceiling wall (91) with seven segment accommodation holes (11) arranged in a figure eight shape”. For example, an outer case for a 7-segment numerical display can be manufactured. <Item 4> When the invention of the above-mentioned item 1 is carried out, the segment housing hole (11) for housing the light emitting segment is formed in the ceiling wall (91) of the case main body (10) made of a resin material of a high brightness color. A dark layer (15) resin-molded around the segment accommodation hole (11) on the surface of the ceiling wall (91), penetrating both sides.
Are overlapped on each other "to obtain an outer case of a light-emitting display. In this case, since the dark-colored layer (15) is a multi-color molded article formed by resin molding on the surface of the ceiling wall (91) of the case main body (10), the dark-colored layer (15) and the case main body (10) are formed. Are securely bonded, and the dark-colored layer (15) is hardly peeled off.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described together with the illustrated example. FIG. 2 is a partially cutaway perspective view of an outer case (1) of a light-emitting display device for explaining an embodiment of the present invention, and shows a light-emitting diode type light-emitting segment (21) (21).
The segment receiving holes (11) and (11) for accommodating the ceiling wall (91)
A rectangular box-shaped case main body (10) with an open bottom formed in
A dark layer (15) molded of resin on the surface of the case body (10)
Is provided. In addition, a segment receiving hole (13) for a decimal point is formed near the formation area of the segment receiving holes (11) and (11), and these segment receiving holes (11) (11) (13)
The light-emitting diode type light-emitting segments (21) and (21) are accommodated therein.

FIG. 1 is a partial sectional view of a main part of a two-color molding machine for injection-molding the outer case (1). In this one,
A mold (51) is provided between a fixed platen (41) attached to the tip of the first and second cylinders (31) and (32) of the injection machine and a movable platen (40) as an output unit of a mold clamping device (not shown). ) And a mold reversing device (61). [About the mold (51)] The mold (51) is a pair of male molds (55a) (5
5b) and a fixed mold (64) having a female mold for primary molding (65a) and a female mold for secondary molding (65b). * Movable mold (54) The movable mold (54) is provided with a male mold (55a) (55b) that is matched with the female mold for primary molding (65a) and the female mold for secondary molding (65b). At the same time, the molding surfaces of these male molds (55a) and (55b) have the same three-dimensional shape. These males (55a) (5
5b), a molding part (57) for molding the back surface shape of the case main body (10) to be molded is formed, and the molding part (57) is formed.
The segment housing hole (1
1) A convex portion (58) having an outer peripheral shape corresponding to the peripheral wall shape of (11).
(58) is protruding. That is, the outer shapes of the male molds (55a) and (55b) are, as shown in FIG. 2, the lower vertical plane (26) of the lower open vacant chamber (12) formed in the case main body (10) and the upper end thereof. From the back surface (17) of the ceiling wall (91) which is continuous in the horizontal direction and the peripheral side walls (18) (18) of the segment accommodation holes (11) (11) following the ceiling wall (91). * Fixed mold (64) The fixed mold (64) has a female mold for primary molding that fits externally with the male mold (55a) of the first molding station (A) for molding the case body (10).
(65a) and a second forming station for forming the dark layer (15)
A female mold for secondary molding (65b) that fits over the male mold (55b) of (B) is provided, and the former female mold for primary molding (65a) matches the outer shape of the case body (10). It has an inner surface shape.

On the other hand, the female mold for secondary molding (65b) has a dark color layer (15).
The female mold for secondary molding (65b) is a small convex which abuts against the convex portions (58) and (58) of the male mold (55b) located at the second molding station (B). The part (60) (60) protrudes from the bottom wall and is a darker layer (15) than the primary molding female mold (65a).
The molding recess (62) is deeper by the thickness of the mold. [About the mold reversing device (61)] The movable mold (5
The mold reversing device (61) to which 4) is attached is fixed to the movable platen (40) which is the output part of the mold clamping device, and the movable mold (54)
With the fixed mold (64) separated from the movable mold (54),
It has a function of moving the male molds (55a) and (55b) between the first molding station (A) and the second molding station (B) by sequentially rotating the molds in the unit of 0 degrees. [Regarding the molding operation] Next, the molding operation of the outer case of the light emitting display will be described.

First molding station (A) in the injection machine
The first cylinder (31) on the side is filled with a high-brightness color (white in this embodiment) thermoplastic resin, and the other second cylinder (31) is filled with thermoplastic resin.
The second cylinder (32) on the molding station (B) side is filled with a low-brightness (black in this embodiment) thermoplastic resin.

First, the movable mold (54) approaches the fixed mold (64) fixed to the fixed platen (41), and the male mold (55a) (55
b) and female mold for primary molding (65a) and female mold for secondary molding (65b)
To match. Next, when the plasticized thermoplastic resin is injected from the first and second cylinders (31) and (32) by the screws (71) and (72) of the injection machine, the high-brightness thermoplastic resin is injected into the runner (4).
4) From the male mold (55a) located at the first molding station (A)
Then, it is shaped into a molding space surrounded by the female mold for primary molding (65a) to form the case main body (10) (first molding step). On the other hand, in the secondary molding female mold (65b) located at the second molding station (B), a thermoplastic resin of low lightness color is formed from the first cylinder (31) via the runner (45), Thereby, the dark layer (15) is injection-molded on the surface of the case main body (10) (second molding step). Next, the mold clamping device is operated to move the movable mold (5
With 4), the movable platen (40) is retracted to the state shown in FIG. 3 (mold opening step). At this time, the outer case (1) consisting of the case main body (10) and this and the dark layer (15) due to the mold gradient
Spontaneously remain on the male (55a) (55b) side. In this state, remove the outer case from the male mold (55b) of the second molding station (B).
(1) Take out.

Next, by rotating the mold reversing device (61), the first
The male mold (55a) of the molding station (A) is moved to the second molding station (B) and the second molding station (B) is moved.
The male mold (55b) of (B) is moved to the first molding station (A), and then the movable mold (54) is moved closer to the fixed mold (64) to make the male mold (55).
(55a) (55b), the female mold for primary molding (65a) and the female mold for secondary molding (65b) are matched, and the first and second cylinders (31) (3)
Inject thermoplastic resin from 2). Then, when shaping the resin for the dark layer (15) in the female mold for secondary molding (65b),
Male type (55b) in segment housing hole (11) of case main body (10)
Since the convex portions (58) and (58) of the segment are densely inserted, the plasticizing resin for the dark layer (15) is
(11) There is no fear of adhering to the inner peripheral wall. That is, the case subject
Unlike the above-described conventional one in which the undried paint applied to the surface of the ceiling wall (91) of (10) runs down the inner peripheral wall of the segment accommodation hole (11) and drips, the segment accommodation hole (11 ) Makes it difficult for the material of the dark layer (15) to adhere to the inner peripheral wall. Also, even if the surface of the case main body (10) is wavy due to sink during molding,
The dark layer (15) is formed by resin molding the dark layer (15) on the surface.
Can be made smooth.

By repeating the above injection molding operation, the outer case (1) of the luminous display as shown in FIG. 2 in which the segment accommodation holes (11) and (11) penetrating from front to back are arranged in a figure eight shape is formed by the second molding. It can be taken out from the male mold (55b) of the station (B) sequentially.

In the above embodiment, two male models (55
a) A movable mold (54) having (55b) and a female mold (65
The outer case (1) was molded using a mold comprising a) and a fixed mold (64) having a female mold for secondary molding (65b). However, the mold for molding the case body (10) and the case body (1
Separately prepare molds for forming the dark layer (15) on the surface of (0),
The case body (10) formed by the former mold may be inserted into the latter mold to form the dark layer (15) on the ceiling wall (91).

Further, in the above embodiment, the outer case (1) is manufactured by the core rotation method in which the movable mold (54) is rotated. However, after the case main body (10) is formed, the male mold is slightly retracted. And the space formed by the receding dark layer (1
The core back method of injecting the resin for 5) may be adopted.

It is also possible to adopt a method of simultaneously injecting the materials of the case main body (10) and the dark layer (15) from different injection mechanisms. In the above embodiment, a light emitting diode is used as the light emitting segment (21). However, the light emitting segment (21) is not limited to the light emitting diode as long as it is a light emitting source.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of an injection molding machine illustrating an embodiment of the present invention.

FIG. 2 is a perspective view of a partially cutout of an outer case of the light emitting display formed by the injection molding machine of FIG.

FIG. 3 is an explanatory diagram of an injection molding operation.

FIG. 4 is an explanatory view of a conventional example.

[Explanation of symbols]

(10) ・ ・ ・ Case main body (11) ・ ・ ・ Segment accommodation hole (21) ・ ・ ・ Light emitting segment (51) ・ ・ ・ Dark color layer (91) ・ ・ ・ Ceiling wall

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/00-45/84 G09F 9/00

Claims (4)

(57) [Claims] 1. A segment accommodating hole (11) for accommodating a light-emitting segment penetrates a ceiling wall (91) of a case main body (10) made of a resin material of a high brightness color from front to back. (91) on the surface of the segment accommodation hole (1
In the method for manufacturing an outer case of a light-emitting display in which a dark layer (15) overlaps around 1), the dark layer (15) is injection-molded with a resin material on a surface of the ceiling wall (91). A method for manufacturing an outer case of a light emitting display. 2. The method of manufacturing an outer case of a light-emitting display according to claim 1, wherein the method of injection-molding the dark layer (15) with a resin material on the surface of the ceiling wall (91) comprises: A male mold having a convex portion having an outer peripheral shape corresponding to the peripheral wall shape of the housing hole (11) and molding the back surface shape of the case main body (10); and a primary molding for molding the surface shape of the case main body (10). Female mold, and a secondary molding female mold for molding the surface shape of the dark layer (15) is prepared, and a high-brightness color resin is formed in a molding space surrounded by the male mold and the primary molding female mold. Forming a case body (10) by shaping; and after the first forming step, the case body (10) is formed on the male mold.
A mold opening step of separating the female mold for primary molding from the male mold in a state where the resin remains, and after the mold opening step, the male mold and the female mold for secondary molding are mold-matched to form the secondary molding. A method for manufacturing an outer case of a light emitting display, comprising a second molding step of shaping a resin having a low lightness color into a female mold to form the dark layer (15). 3. The method for manufacturing an outer case of a light-emitting display device according to claim 1, wherein the ceiling wall (91) has seven segment accommodation holes (8) arranged in a figure eight shape. 11) A method for manufacturing an outer case of a light-emitting display device, wherein (11) is formed. 4. A segment accommodating hole (11) for accommodating a light-emitting segment penetrates through a ceiling wall (91) of a case main body (10) made of a resin material of a high brightness color from front to back. (91) on the surface of the segment accommodation hole (1
An outer case for a light-emitting display, in which a resin-molded dark layer (15) overlaps around 1).