JPH0217315B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a processing method for chamfering a side hole formed in a side wall of a gutter-like wiring duct made of a resin material.

PRIOR ART When a side hole is formed in the side wall of a gutter-like wiring duct and the electric wire inside the wiring duct is pulled out from this side hole, the resin coating of the electric wire comes into contact with the peripheral corner of the side hole. This may cause damage and the inconvenience of exposing the core wire.

In order to eliminate this inconvenience, the peripheral corner of the side hole is chamfered.

In this case, in the conventional processing method, a punch or die having a tapered portion that is compatible with the side hole is inserted into the side hole and press-welded.

This processing method is effective when the side hole is formed independently, but if the side hole is connected to the upper end of the side wall of the wiring duct by a cut groove, chamfering is not possible. It has the disadvantage of not being possible.

That is, as shown in FIG. 7, a wiring duct made of a resin material such as vinyl chloride has a side hole 11A formed in the side wall 11 of a gutter-shaped duct body 10, and the upper end of the side hole 11A is connected to the side wall 11. It has a structure in which it communicates with the upper edge through a cut groove 11B, and in normal use, the electric wires inside the duct body 10 can be pulled out from the side hole 11A in the same way as in conventional wiring ducts. When drawing out the wire, the wire is inserted into the side hole 11A through the cut groove 11B, or if the wire is thicker than the groove width of the cut groove 11B, the upper end of the wall 12 between adjacent side holes 11A, that is, the cut By bending both sides of the groove 11B in opposite directions to widen the width of the cut groove 11B and inserting the wire therethrough, there is an advantage that there is no need to insert the wire from the end of the wire to be drawn out into the side hole 11A. ing.

Furthermore, when a large number of electric wires are to be drawn out from one side hole 11A, the two adjacent side holes can be separated by breaking off the wall portion 12 adjacent to the side hole 11A from its base end. If the wires are substantially connected to form one large space, it is convenient that a large number of electric wires can be drawn out from the space.

In a wiring duct with such a configuration,
As in the past, when a punch or die having a tapered portion that is compatible with the side hole 11A is inserted and pressed into the side hole 11A, the wall portion 12 is pushed and moved according to the gap between the grooves 11B. Therefore, the pressure welding process required for chamfering becomes impossible.

Therefore, even in a wiring duct in which the side hole 11A is connected to the upper end of the side wall 11 by the cut groove 11B, the side hole of the wiring duct allows the peripheral corner of the side hole 11A to be reliably chamfered. A chamfering method has already been proposed by the present inventor (Japanese Patent Publication No. 33260/1983).

In this prior art, after forming a side hole 11A and a cut groove 11B extending from the side hole 11A to the upper edge of the wiring duct body 10 in the side wall 11 of a gutter-shaped wiring duct body 10 made of a resin material, The wall portion 12 between adjacent side holes 11A is connected to both side holes 1.
Press from the 1A side with a punch or die, and by the pressure, both holes 11
The opposing peripheral corners of A are chamfered.

Problems to be Solved by the Invention However, in the above-mentioned prior art, the side hole 11A and the cut groove 11B extending from the side hole 11A to the upper edge of the wiring duct body 10 are formed in the side wall 11 of the wiring duct body 10. From there, chamfering is performed.

That is, two adjacent mutually already formed
The protrusions of the punch and die are fitted into each of the side holes 11A in such a way that they are aligned so as to touch the peripheral corner of one side hole 11A and the peripheral corner of the other side hole 11A. Wall portion 1 between both side holes 11A
2 from both sides, and the circular arc portions press the opposing circumferential corner portions of the both side holes 11A from the left and right to chamfer the holes.

Therefore, the already formed side hole 11A
If the position of the punch or die is not aligned with the position of the chamfer, proper chamfering cannot be performed.
However, in practice this alignment is extremely difficult. Further, there is a problem in that the end face is unnecessarily raised when the punch or die is pressed, spoiling the appearance.

Therefore, the present invention has been made in view of the background of these conventional techniques, and provides a method for machining a side hole in a wiring duct, in which the above-mentioned positioning can be easily performed and chamfering can be performed with a good appearance. The purpose is to

Means for Solving the Problems The method for processing side holes in a wiring duct according to the present invention includes:
A gutter-shaped wiring duct body made of a resin material is heated and softened, and a pair of mold members are pressed against each other from both sides in the thickness direction at predetermined positions on the side wall of the heated and softened wiring duct body, and the mold members are pressed against each other from both sides in the thickness direction. A side hole or a side hole and a recess corresponding to the outer contour of a kerf extending from the side hole to the upper end edge of the wiring duct body are formed by a recess forming blade protruding from the opposing surface, and at least the recess is formed. After chamfering the corners of the outer periphery of the side hole using an arc-shaped pressing surface continuous to the outer periphery of the blade, the blank surrounded by the recess is punched out and removed. It is something to do.

According to the present invention, the wiring duct body is connected to the wiring duct body from the side hole or the side hole and the side hole by the depression forming blade portions which are provided at predetermined positions of the wiring duct body on the opposing surfaces of the pair of mold members. A recess corresponding to the outer contour of the kerf extending to the upper edge is formed, and the corner of the outer peripheral edge of the side hole is neatly chamfered by a pressing surface continuous to at least the outer peripheral part of the recess forming blade part. .

Embodiment FIG. 1 shows a gutter-shaped wiring duct body 1 made of a resin material. In the figure, the side wall 2 of the wiring duct body 1 is formed with a side hole 2A shown by a phantom line and a cut groove 2B extending from the side hole 2A to the upper edge of the wiring duct body 1. The peripheral corners are chamfered.

FIG. 2 is a front view showing an example of a recess forming chamfering device, in which 3 and 4 indicate a pair of mold members, one mold member, that is, the upper mold 3, and the other mold member, that is, the lower mold 4. They are placed facing each other vertically. Then, on the mold surface of the upper mold 3, the side hole 2A and the cut groove 2 shown in FIG.
Hollow forming blade part 3 having a shape corresponding to the outline of B
a is provided in a protruding manner, and the mold surface of the lower mold 4 is also provided with a similar recess forming blade portion 4a as described above.

Arc-shaped pressing surfaces 3b and 4b are formed on the outer periphery of each of the depression forming blade portions 3a and 4a that form the outer contour of the side hole 2A in both mold members 3 and 4, respectively.

The upper mold 3 is attached to a ram (not shown) and moves up and down together with the ram. Further, the lower die 4 is fixed to a bolster (not shown). Then, the wiring duct main body 1 is heated and softened in advance and is positioned at the position shown in FIG. 2, and then intermittently transferred in the direction of the arrow.
The upper die 3 is raised and lowered in synchronization with this transfer.

That is, by lowering the upper mold 3, as shown in FIG.
Recesses 5 and 6 corresponding to the outer contour of the kerf 2B extending from A to the upper edge are formed, and the corners of the outer peripheral edge of the side hole 2A are chamfered by the arcuate pressing surfaces 3b and 4b.

In this way, depressions 5,
FIG. 4 shows a plan cross-sectional view of the wiring duct main body 1 on which the wiring duct 6 is formed and chamfered.

Next, as shown in FIG. 5, the blank 9 is punched out using a punch 7 and a die 8 to obtain a finished product shown in FIG. 6. That is, according to the present invention, chamfering can be performed without positional deviation with respect to the side hole 2A, and the end face can be prevented from becoming unnecessarily raised.

In the above embodiment, only the outer circumferential corner of the side hole 2A is chamfered, but according to the present invention, it is also possible to simultaneously chamfer the outer circumferential corner of the cut groove 2B. It is.

Further, the cut groove 2B can be omitted, only the side hole 2A can be formed independently, and the outer peripheral corner of the side hole 2A can also be chamfered in the same manner.

Furthermore, although it has been explained that the wiring duct body 1 is heated and softened in advance to form a recess and be chamfered, it is possible to perform the above-mentioned processing more easily by heating the upper mold 3 and the lower mold 4. Not even.
Normally, duct molded products made of vinyl chloride, etc., have a fine texture on the outer surface that comes into contact with the surface of the mold during molding, resulting in a smooth surface, but the inside is rougher than the surface, and the cross section when cut is the inner surface. appears, making it rough. Because of this rough surface, burrs are likely to occur when cutting at room temperature, which may damage the surface coating of the wire. However, in the present invention, since the depressions are formed and the chamfering process is performed in a heated and softened state, the surface is finished beautifully and smoothly, and there is an advantage that the above-mentioned wire coating is not damaged.

Effects of the Invention As explained above, according to the present invention, the chamfering process is performed at the same time as forming the side hole or the depression corresponding to the outer contour of the side hole and the cut groove extending from the side hole to the upper edge. , positioning is easy, and the inconvenience that the end face is unnecessarily raised can be eliminated, and the finishing accuracy can be improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a wiring duct body with side holes processed according to the present invention, FIG. 2 is a schematic front view showing an example of a recess forming chamfering device, and FIG.
The figure is a front view of the hollow and chamfering process, Figure 4 is a cross-sectional view of the same, Figure 5 is an explanatory diagram of the blank removal process, and Figure 6 is a cross-sectional view of the processed wiring duct.
FIG. 7 is a perspective view showing an example of a conventional wiring duct. 1...Wiring duct body, 2...Side wall, 2A...
Side hole, 2B...cut groove, 3, 4...pair of mold members,
3a, 4a...dent forming blade portion, 3b, 4b...pressing surface, 5, 6...dent, 9...blank.

Claims (1)

[Claims] 1. A gutter-shaped wiring duct body made of a resin material is heated and softened, and a pair of mold members are pressed against each other from both sides in the thickness direction at predetermined positions on the side walls of the heated and softened wiring duct body, thereby forming both mold members. A side hole or side hole and a recess corresponding to the outer contour of the cut groove extending from the side hole to the upper end edge of the wiring duct body are formed by a recess forming blade protruding from the opposing surface of the wiring duct body, and at least the recess After chamfering the corner of the outer periphery of the side hole using an arcuate pressing surface continuous to the outer periphery of the forming blade, the blank surrounded by the recess is punched out and removed. A method for machining side holes in wiring ducts.