JPS63283411A - Manufacture of duct for wirings - Google Patents

Abstract

PURPOSE:To obtain a duct for long wirings continued by the repetition of molding by forming an uneven surface on the molding face of the end of the duct of a metal mold for the end face. CONSTITUTION:The end 32 of a metal mold 31 for molding one longitudinal end face of a duct has the same sectional shape as that of a duct body to be molded, and an injection molding space is formed between it and the molded resin 33. The molding face of the end of the duct of the end 32 has a protrusion 34 at the thicknesswise center, and faces 35, 36 parallel to the longitudinal surface of the duct on both inner and outer faces of the protrusion 34. The thickness X and the depth Y of the protrusion are determined at the optimum values by the thickness (t) and the material of the resin of the duct, and may obtain thermal capacity to melt the surface layer of the molded resin by the melted resin. Thus, the duct for long wirings continued by the repetition of the injection moldings can be manufactured.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method of manufacturing a wiring duct, and more specifically,
This invention relates to a method for manufacturing a wiring duct using a plastic injection molding method.

<Prior Art> As shown in FIG. 5, a wiring duct has electric wire outlet ports 4 continuously bored in both side walls 2.3 of the bottom surface 1 of a long, curved main body. A fitting part 8.9 for fitting with the lid 7 is formed on the upper edge of . have. When the main body is in use with M7 fitted, both side walls 2 and 3
are parallel to each other, but in the unfitted state, the upper edges are shaped to expand slightly to generate the frictional force for fitting.

In the conventional manufacturing method of such a wiring duct, the entire duct is molded by extrusion molding, and then the wire outlet 4-4 is punched out using a press.

In response to this, the present inventor has separately proposed a method for manufacturing a long wiring duct using a novel plastic injection molding method (unpublished).

<Problems to be solved by the invention> According to this prior invention, since the next injection molding is performed with the injection molded product displaced in the longitudinal direction of the duct, the end face of the previous molded product and the newly injected product are A problem arises in joining with the molten resin.

An object of the present invention is to provide a manufacturing method in which the bond between a molded resin and a molten resin is strengthened by means of an hour wheel.

<Means for Solving the Problems> The manufacturing method of the present invention has a long gutter shape in which left and right side walls rise from both sides of the bottom plate and a fitting portion is formed on the upper edge of the side walls. An injection molding method for a wiring duct having a wire outlet formed in the side wall, which includes a side mold for molding both the inner and outer surfaces of the bottom plate and left and right side walls, and an end face mold for suppressing one end face in the longitudinal direction of the duct. Using a mold device equipped with a mold, after injection molding, the side mold is released, and then,
In a method for manufacturing a continuous molded body by displacing the molded body in the longitudinal direction, and then performing the next injection molding with the side mold being set to a state before release, the duct of the end face mold is It is characterized in that an uneven portion including surfaces parallel to the surfaces of the bottom plate and the left and right side walls is formed on the molded surface of the end face.

The formation of an uneven portion including surfaces parallel to the surfaces of the bottom plate and left and right side walls of the duct main body means that the convex portion 34 is formed at the center in the thickness direction as shown in FIG. When surfaces 35 and 36 parallel to the duct surface are formed on both sides of the convex part, as shown in FIG. When surfaces 38 and 39 parallel to the duct surface are formed, as shown in Figure fC1 of the same figure, a convex portion 40 is formed on the inner surface of the duct, and a surface 41 parallel to the duct surface is formed on the outside of the convex portion. In this case, as shown in FIG. 4D, a convex portion 42 may be provided on the outer surface of the duct, and a surface 43 parallel to the duct surface may be formed inside the convex portion.

Effect> According to the method of the present invention, when the newly injected molten resin comes into contact with the end of the duct body that has already been molded, the surface of the molded resin melts and softens due to the heat of the molten resin, and during that time, A strong bond with no interface can be obtained.

<Example> FIG. 1 shows a cross-sectional view of a mold apparatus used for carrying out the method of the present invention.

The mold is assembled in an inverted position with the bottom 1 of the duct body facing upward, and an injection port (not shown) is provided on the top surface of the bottom 1. The first mold 11 molds the outer surface of the bottom, the second mold 12 molds the outer surface of one side wall, the third mold 13 molds the outer surface of the other side wall, and the fourth mold 14 molds the outer surface of one side wall. The fifth mold 15 molds a portion of the inner surface and the bottom inner surface of the other side wall and a portion of the bottom inner surface.

The fourth and fifth molds 14 and 15 are located above the inside of the duct (first
Projections 21 and 22 are integrally formed and extend outward from the left and right from the bottom (in the figure), and elongated holes 23 and 24 having long diameters in the projecting direction are formed at the bases of the projections 21 and 22, and the fixing shaft 17, 18 is inserted through the elongated hole and supported with a degree of freedom. Compression springs 19 and 20 are provided at the tip of the protrusion 21.22 to press the protrusion 21.22 toward the center, and compression springs 19 and 20 are provided below the tip of the protrusion 21.22. Springs 25 and 26 are provided to apply a pressing force in a direction to release the mold on the inner surface of the duct side wall.

In order to allow rotation of the fourth and fifth molds 14 and 15, the second
Recesses 27 and 28 are formed between the third mold and the third mold. The sixth mold 16 is wedge-shaped and penetrates between the fourth and fifth molds 14 and 15.
The overlapping of the fifth and sixth molds defines the distance between the inner surfaces of the left and right side walls of the duct.

FIG. 2 shows the mold release state of this mold apparatus.

The first mold 11 moves upward, and the second and third molds 12,1
3 is displaced outward to the left and right and released from the mold. When the sixth mold retreats significantly downward, a space is created between the fourth and fifth molds 14 and 15, and the molds 14 and 15 are pushed into the elongated holes 23 and 20 by the pressing force of the compression springs 19 and 20. is displaced toward the center within an allowable range, and rotated around the shaft 17.18, which serves as a fulcrum, by the pressing force of the compression springs 25 and 26, until the tips 29.30 forming the bottom surface of the duct come into contact. to release the mold from the inside of the duct.

FIG. 3 shows a longitudinal cross-sectional view (cross section AA in FIG. 1) of a seventh mold for molding one end surface in the longitudinal direction of the duct. The tip 32 of the seventh mold 31 has the same cross-sectional shape as the duct body to be molded, and an injection molding space is formed between this and the molded resin 33. Figure 4 (Figure 81 shows the tip 3
An enlarged view of the molded surface of the duct end face of No. 2 is shown. It has a convex portion 34 at the center in the thickness direction, and surfaces 35 and 36 parallel to the longitudinal surface of the duct are formed on both the inner and outer surfaces of the convex portion 34.

The optimal values for the thickness X of the convex portion 34 and the depth Y of the convex portion are determined by the thickness t of the duct, the material of the resin, etc., but in short, the heat capacity is sufficient to melt the surface layer of the molded resin with the molten resin. It is enough if you can get it.

Fig. 4(b), (C1) and (d1) show examples of modification of the molding surface of the duct end face. In each figure, 3B, 39.41
43 represents a plane parallel to the longitudinal surface of the duct.

<Effects of the Invention> According to the present invention, a continuous long wiring duct can be manufactured by repeating injection molding, and at that time, the boundary between the molded part and the new molded part is integrated by fusion bonding. A strong wiring duct can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the molding state of the mold device used for carrying out the present invention, FIG. 2 is a cross-sectional view showing the molding state of the mold device shown in FIG. 1, and FIG. , A-A sectional view in Figure 1, Figure 4 (a) is an enlarged view of section B in Figure 3, Figure 4 (b)
, (C) , (D1 is an enlarged view showing a modified example of FIG. 4FA1, and FIG. 5 is a perspective view showing an example of a wiring duct manufactured by the method of the present invention.1... Bottom plate 2.3... Side wall 11.12.13.14.15... Side mold 31.
... End face mold 35.36, 38, 39.41.43 ... Surfaces parallel to the longitudinal surface of the duct 34.37, 40.42 ... Uneven portion Patent applicant Ashiwa Denki Co., Ltd. Patent Attorney Nishi 1) Shin■ Figure 3 Figure 2 Figure 4 Figure 5 7

Claims (2)

[Claims] (1) Injection of a wiring duct that has a long gutter shape with left and right side walls rising from both sides of the bottom plate and a fitting part formed on the upper edge of the side walls, and an electric wire outlet formed in the left and right side walls. The molding method uses a mold device equipped with a side mold for molding both the inner and outer surfaces of the bottom plate and left and right side walls, and an end mold for suppressing one end surface in the longitudinal direction of the duct, and after injection molding. Continuous molding is performed by releasing the side mold, then displacing the molded body in the longitudinal direction, and then setting the side mold to the state before releasing and performing the next injection molding. In the method for manufacturing a wiring duct, the molding surface of the end face of the duct of the end face mold is formed with an uneven portion including a surface parallel to the bottom plate and the surfaces of the left and right side walls. Production method. (2) The side molds include a first mold for molding the outer surface of the bottom surface, second and third molds for molding the outer surfaces of the left and right side walls, and the right and left molds for molding the outer surfaces of the left and right walls. A mold for molding the inner surfaces of both side walls, in which left and right protrusions extending from above the upper edges of the side walls outward to the left and right are integrally formed, and fourth and fifth molds each having a fulcrum at the root of the protrusions. A wiring duct according to claim 1, comprising a sixth mold that penetrates between the fourth and fifth molds and is displaced in the vertical direction of the duct. Production method.