JP3811264B2 - Box structure by resin molding and method for manufacturing the box structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a box structure integrally formed of a synthetic resin and a method for manufacturing (manufacturing) the box structure.
[0002]
[Prior art]
For box-shaped devices, such as portable portable devices such as portable broadcasting devices, it is necessary to use a box-type structure with a storage space for storing accessories such as power cords, microphones, spare batteries, etc. There is.
10 shows a perspective view of a conventional box-type structure as viewed from above, and FIG. 11 shows a perspective view as seen from the back side. 10 and 11, the recess 14 formed on the upper surface plate 10 of the box-type structure leaving the band-like portions 12 at both ends is used as a storage space for accessories and the like.
[0003]
[Problems to be solved by the invention]
In the conventional box-type structure described above, there is a dead space 16 that is an unnecessary space such as a hatched portion, and there is a problem in that the box-type structure is increased in size and weight.
In order to eliminate the dead space, when the box-type structure as shown in FIG. 12 and FIG. 13 is used, the movable side mold has a shape as shown in FIG. Since it is not supported, a large force is applied in either the outer or inner direction due to the injection pressure during resin molding, which reduces the accuracy of the product (box structure) and significantly shortens the life of the mold. was there. In addition, when the mold leg portion 18 is made thick in order to ensure the strength of the mold leg portion 18, there is an inconvenience that the mold becomes large and the manufactured box-type structure also becomes large.
[0004]
The present invention has been made in view of the above points, and an object of the present invention is to eliminate dead space by eliminating dead space, and thus to achieve downsizing and weight reduction. Resin that can prevent damage to the mold, improve durability, and prevent distortion of the mold during molding to ensure the accuracy of the product (box structure) An object of the present invention is to provide a box structure by molding and a method for manufacturing the box structure.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the resin-molded box-shaped structure of the present invention is made of a resin-made upper box-type body on the upper surface plate, leaving a part of the upper surface plate as a band at both ends. The concave portion is formed integrally by resin molding, and the thickness of the side plate of the upper box type main body is larger than the thickness of the side plate of the concave portion in the cross-sectional shape of the belt-like portion and the concave portion. It is comprised so that several biting holes may be provided in the connection part (refer FIGS. 1-4).
In the above box structure, the side plate of the upper box type main body is inclined so as to be positioned outward as it goes downward, and the concave side plate is inclined so as to be positioned inside as it goes downward. (See FIGS. 2 to 4).
[0006]
In the method for manufacturing a box-shaped structure according to the present invention, a resin concave portion is integrally formed on a top plate of a resin upper box type main body by resin molding, leaving a part of the top plate as a strip at both ends. In the manufacturing method of the box-type structure,
The movable side mold and the fixed side mold for forming the side plate of the upper box type main body, the side plate of the concave portion and the bottom plate of the concave portion, and the gap for forming the side plate of the upper box type main body form the side plate of the concave portion. The movable side mold is covered with the fixed side mold so that the gap is larger than the gap, and a plurality of cutouts are provided inside the upper end of the movable side mold, and the fixed side mold is fitted with these cutout parts. It is characterized by injecting molten resin from the upper gate of the movable side mold after providing a plurality of projections to be joined and restricting the movable side mold from falling inward (see FIGS. 1 to 9). .
[0007]
In the above box structure manufacturing method, the movable side mold is formed so as to spread downward, and the fixed side mold forms the side plate of the upper box type main body with this movable side mold. In order to form a gap for forming the gap and a gap for forming the side plate of the recess, it is preferable to have a space that expands downward (see FIGS. 8 and 9).
By using such a mold, the molten resin can be poured smoothly while restricting the movable mold from falling inward.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications.
1 shows a perspective view of a box-type structure according to a first embodiment of the present invention, FIG. 2 shows a cross section taken along line AA, FIG. 3 shows a cross section taken along line BB, and FIG. The enlarged perspective view of the part enclosed with the chain-line circle is shown.
As shown in FIGS. 1 to 4, a part of the upper surface plate 22 is left on both ends (both sides) as band-shaped portions (band-shaped plates) 24 on the upper surface plate 22 of the resin upper box type main body 20. The recess 26 is integrally formed by resin molding. This recess 26 becomes a storage space for accessories and the like. A storage space is also formed below the remaining top plate 22.
[0009]
2 and 3, the thickness t ₂ of the side plate 28 and the band-shaped portion 24 of the upper box-type main body is larger than the thickness t ₁ of the side plate 30 of the recessed portion 26 in the cross-sectional shape of the band-shaped portion 24 and the concave portion 26 shown in FIGS. Largely formed. In addition, a plurality of biting holes 32 are provided in the connecting portion between the belt-like portion 24 and the side plate 30 of the concave portion 26. It is preferred that the thickness of the bottom plate 34 of the recess and t _1, thicker than t _1, or may be thinned. Reference numeral 36 denotes a gate position.
[0010]
The side plate 28 of the upper box-type main body is inclined so as to spread and be located outside as it goes downward, and the side plate 30 of the recess 26 is inclined so as to be located inside as it goes downward. A bottom plate 34 is connected to the lower ends of the side plates 30 and 30 of the recess 26.
[0011]
Next, an example of a method for manufacturing the box structure will be described with reference to FIGS.
A movable side mold 38 (see FIG. 6) and a fixed side mold 40 (see FIG. 5) for forming the side plate 28 of the upper box body, the side plate 30 of the recess 26 and the bottom plate 34 (see FIG. 2) are shown in FIG. As shown in FIGS. 7 to 9, the movable side mold 38 is fixed so that the gap 42 for forming the side plate 28 of the upper box mold main body is larger than the gap 44 for forming the side plate 30 of the recess. Cover with the side mold 40 and arrange. Further, as shown in FIGS. 6 and 8, a plurality of biting portions 48 are provided inside the upper end of the mold leg 46 of the movable mold 38, and as shown in FIGS. 5 and 8, the fixed mold 40 is fixed. A plurality of protrusions 50 that closely fit these cut-out portions 48 are provided. 52 is a gap for forming the belt-like portion 24.
In this way, after restricting the movable side mold 38 from falling inward (right side in FIG. 8), the molten resin is injected from the upper gate (pouring gate) of the fixed side mold to integrate the box-type structure. To form.
[0012]
As shown in FIGS. 8 and 9, the movable side mold 38 is formed so as to expand (thicken) as it goes downward, and the fixed side mold 40 is interposed between the movable side mold 38 and the movable side mold 38. There is a space 54 that expands downward as the gap 42 for forming the side plate of the upper box type main body, the gap 44 for forming the side plate of the concave portion, and the gap 52 for forming the strip-shaped portion are formed. is doing.
With this configuration, the molten resin flows first in the direction of the wide gap 42, and the movable side mold 38 tends to fall inward (rightward in FIG. 8) by the injection pressure. Since 50 is closely fitted, the movable mold 38 is restricted from falling inward. For this reason, damage to the mold is prevented, and the accuracy of the product (box structure) itself can be ensured. Since the molten resin first flows into the wide gap 42 and then flows into the narrow space 44, the movable mold 38 does not fall outward (leftward in FIG. 8). 5 is combined with the movable mold 38 shown in FIG. 6, the fixed mold 40 shown in FIG. 5 is turned upside down and upside down in FIG. Thus, it is combined with the movable mold 38 shown in FIG. Reference numeral 56 denotes a bottom plate forming portion for forming the bottom plate of the recess.
The box-type structure obtained by the above manufacturing method has the same height between the lower end of the side plate 28 of the upper box-type main body and the bottom plate 34 of the recess. However, as shown in FIG. A box-shaped structure in which the lower end of the side plate 28 is located below the side plate 34 can be manufactured by the same method as described above by deforming the fixed side mold and the movable side mold.
[0013]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects.
(1) Since unnecessary space (dead space) can be reduced, it is possible to reduce the size and weight of equipment using a box-type structure.
(2) Since the mold can be prevented from falling down, the mold can be prevented from being damaged, and the durability of the mold can be improved and the life can be extended.
(3) Since the mold is not distorted during resin molding, the accuracy of the product (box structure) can be ensured.
[Brief description of the drawings]
FIG. 1 is a perspective view of a box-shaped structure formed by resin molding according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a cross-sectional view taken along line BB in FIG.
4 is an enlarged perspective view of a portion surrounded by a chain line circle in FIG. 3;
FIG. 5 is a perspective view of a fixed-side mold.
FIG. 6 is a perspective view of a movable mold.
7 is a conceptual cross-sectional view when the movable side mold shown in FIG. 6 is cut along line CC in a state where the fixed side mold and the movable side mold are combined. FIG.
FIG. 8 is a cross-sectional view of the main part in a state where the movable side mold and the fixed side mold are combined, and around the biting portion.
FIG. 9 is a cross-sectional view of a main part in a state where the movable side mold and the fixed side mold are combined, and a part other than the cut-out part.
FIG. 10 is a perspective view showing an example of a conventional box-type structure as viewed from above.
11 is a perspective view of the box-shaped structure shown in FIG. 10 as viewed from the bottom.
FIG. 12 is a perspective view showing another example of a conventional box structure as viewed from above.
13 is a perspective view of the box-type structure shown in FIG. 12 as seen from the bottom surface.
14 is a cross-sectional explanatory view of a movable side mold when the box-shaped structure shown in FIGS. 12 and 13 is molded. FIG.
[Explanation of symbols]
10, 22 Top plate 12, 24 Band-shaped part (band-shaped plate)
14, 26 Recess (storage space)
16 Dead space 18, 46 Mold leg 20 Upper box mold body 28 Side plate 30 of upper box mold body Side plate 32 of recessed portion Cutout hole 34 Bottom plate of recessed portion 36 Gate (pouring gate) position 38 Movable side mold 40 Fixed side mold 42 Wide gap 44 Narrow gap 48 Cut-out portion 50 Projection 52 Gaps 54 for forming the band-shaped portion Widening space 56 Bottom plate forming portion

Claims (4)

  On the upper surface plate of the resin upper box type main body, a resin concave portion is integrally formed by resin molding leaving a part of the upper surface plate as a band portion at both ends, and in the cross-sectional shape of the band portion and the concave portion, A box formed by resin molding, wherein the thickness of the side plate of the upper box-type main body is formed to be larger than the thickness of the side plate of the concave portion, and a plurality of biting holes are provided at the connecting portion between the belt-like portion and the concave portion. Mold structure.   2. By resin molding according to claim 1, wherein the side plate of the upper box-shaped main body is inclined so as to be positioned outward as it goes downward, and the side plate of the concave portion is inclined so as to be positioned as it goes downward. Box structure. In the manufacturing method of the box-shaped structure in which the resin concave portion is integrally formed by resin molding, leaving a part of the upper surface plate as a strip at both ends on the upper surface plate of the resin upper box type main body,
A movable side plate for forming the side plate of the upper box type main body, the side plate of the concave portion, and the bottom plate of the concave portion so that the thickness of the side plate of the upper box type main body of the box structure is larger than the thickness of the side plate of the concave portion. The movable mold is covered with the fixed mold so that the gap for forming the side plate of the upper box mold main body is larger than the gap for forming the concave side plate. After providing a plurality of cutouts inside the upper end of the movable mold, and providing a plurality of protrusions that fit into these cutouts on the fixed mold to restrict the movable mold from falling inward A method for producing a box structure by resin molding, characterized in that molten resin is injected from an upper gate of a movable mold.   The movable side mold is formed so as to expand as it goes downward, and the fixed side mold forms a gap and a side plate of a recess for forming a side plate of the upper box mold body between the movable side mold and the movable side mold. The method for producing a box-shaped structure by resin molding according to claim 3, wherein a space that expands downward is formed so that a gap is formed.

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