JPH0643054B2 - Through-hole drilling method for cement-based building boards - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming through holes such as nail holes in a cement-based building board such as a roof tile.

[Background Art] Conventionally, when a through-hole is drilled in a cement-based building board, the through-hole is punched in a hardened cement-based building board with a punch pin. There was a drawback that chipping occurred. In order to eliminate this drawback, the green sheet before hardening of the cement-based building board is also punched with a punch pin, but since it is punched with a solid punch pin, it corresponds to the punch pin on the lower mold that supports the green sheet. A die hole must be provided to allow punching waste to be removed from the die hole, and there is a drawback that it is difficult to adjust the punching pin and the die hole when punching.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to enable punching waste to be discharged from a hollow portion of a punching pin when punching with a punching pin, and a carrier plate. Another object of the present invention is to provide a method for punching through holes in a cement-based building board, which can easily punch through holes in a green sheet placed on.

DISCLOSURE OF THE INVENTION The method for punching through holes in a cement-based building board according to the present invention is a green sheet 2 for a cement-based building board placed on a carrier board 1.
At the time of lowering the punching pin 3 from above to punch the through hole 4, the upper surface 8 is provided with the patterning surface 9 on the lower surface and the punching pin 3 having the hollow portion 5 vertically penetrating from the patterning surface 9. Using, the upper die 8 is lowered onto the green sheet 2 to press the pattern surface 9 against the green sheet 2 to form a pattern, and the punching pin 3 is used to punch through holes 4 in the green sheet 2 to form the green sheet 2. Through hole 4
The present invention is characterized in that the punching scraps 6 generated when the holes are punched are discharged upward from the hollow portion 5 of the punching pin 3, and the drawbacks of the conventional example are solved by the configuration described above. That is, the punching pin 3 having the hollow portion 5 penetrating vertically is used, and the punching dust 6 generated when the through hole 4 is punched in the green sheet 2 is discharged upward from the hollow portion 5 of the punching pin 3. The through holes 4 can be formed in the green sheet 2 simply by placing them on the carrier plate 1, so that the through holes 4 can be easily formed. Further, the pattern surface 9 is provided on the lower surface and the punching pin 3 is formed from the pattern surface 9. Using the vertically arranged upper die 8, the upper die 8 is lowered onto the green sheet 2 to press the pattern surface 9 against the green sheet 2 to form a pattern, and the punching pin 3 is used to form the through hole 4 in the green sheet 2. By punching, the pattern can be applied to the upper surface of the green sheet 2 at the same time when the through hole 4 is punched by the punching pin 3.

Hereinafter, the present invention will be described in detail with reference to Examples.

First, a through hole punching device for a cement-based building board for carrying out the present invention will be described. An upper die 8 is mounted on the lower surface of a mounting base 7 that is vertically driven by a pressing device, and a pattern surface 9 for forming a pattern on the green sheet 2 is formed on the lower surface of the upper die 8. The punching pin 3 is provided on the upper die 8 at a position corresponding to the position where the through hole 4 of the green sheet 2 is opened.
Is embedded, and the punching pin 3 is formed with a hollow portion 5 penetrating vertically. The tip of the punching pin 3 is a punching portion 3a, which projects from the lower surface of the upper die 8 by substantially the same thickness as the green sheet 2. Punching part 3a
Has a tapered cylindrical shape whose diameter becomes slightly smaller toward the tip, and the peripheral edge of the tip of the punched portion 3a is sharp. The mounting base 7 is provided with a discharge groove 10 for communicating the hollow portion 5 of the punching pin 3 with the side end surface of the mounting base 7. The carrier plate 1 is formed of a plate material like an iron plate, and a felt 11 for dehydration is laid on the carrier plate 1. Felts 11 are not laid on the carrier plate 1 at positions corresponding to the punching pins 3 but a rubber plate 12 such as urethane rubber is laid. The rubber plate 12 has a disc shape, and is attached to the carrier plate 1 at appropriate positions on the periphery by attaching screws 13. The diameter of the rubber plate 12 is considerably larger than the diameter of the punching pin 3.

Next, the method of the present invention will be described using the apparatus configured as described above. The green sheet 2 of the cement-based building board is formed by paper-making a cement-based material, and the formed green sheet 2 is placed on the carrier board 1 and conveyed.
The carrier plate 1 on which the green sheet 2 is placed is placed and set under the upper mold 8 of the pressing device. In this state, as shown in FIG. 1, the mounting base 7 is lowered to press the upper die 8 against the green sheet 2 and the punching portion 3a of the punching pin 3 is cut into the green sheet 2. A pattern is imparted to the green sheet 2 by pressing the upper die 8 and the tip of the punched portion 3a reaches the rubber plate 12, and the through hole 4 is formed in the green sheet 2 at the punched portion 3a as shown in FIG. Perforated. The punching waste 6 punched through the through hole 4 enters the hollow portion 5. In this manner, when the green sheets 2 are sent one after another and the through holes 4 are punched, the punching scraps 6 are sequentially pushed up inside the hollow portion 5 and reach the discharge groove 10. The punching waste 6 is the discharge groove 10
The air pressure or water pressure, the punching waste 6 in the discharge groove 10
Are ejected and discharged to the outside of the mounting base 7. The through holes 4 are punched in the green sheet 2 as described above. However, since the upper die 8 gives a pattern to the upper surface at the same time when the through holes 4 are punched, the number of steps required for processing can be reduced.
Moreover, the through hole 4 and the pattern are synchronized with each other, and the green sheet 2 does not need to be accurately positioned, and the through hole and the pattern can be accurately formed. Further, since the carrier plate 1 has the rubber plate 12, the impact of the tip of the punching portion 3a of the punching pin 3 is buffered and the punching pin 3 is less likely to be damaged. Moreover, since the diameter of the rubber plate 12 is comparatively large, the punching pin 3 surely corresponds to the rubber plate 12 even if the position of the carrier plate 1 is slightly displaced.

FIG. 4 shows another embodiment. In the case of this embodiment, a mark giving die 14 is provided on the outer circumference of the punching pin 3, and a mark giving ridge 15 is formed on the outer circumference of the lower surface of the mark giving die 14. By doing so, an annular mark groove is formed when the through hole 4 is drilled, and the position of the through hole 4 becomes clear.

EFFECTS OF THE INVENTION The present invention uses a punching pin having a hollow portion that vertically penetrates as described above, and punching dust generated when a through hole is punched in a green sheet is discharged upward from the hollow portion of the punching pin. Through holes can be easily drilled by simply lowering the punching pin from the top of the green sheet on the carrier plate. As in the conventional method, a lower die with die holes can be used or complicated alignment can be performed. It is not necessary, and it does not cause chipping like punching after curing, and uses an upper mold that has a pattern surface on the lower surface and punch pins are hung from the pattern surface. Since it goes down on the green sheet and presses the pattern surface against the green sheet to form a pattern, and punch holes are used to punch through holes in the green sheet.
A pattern can be applied to the upper surface of the green sheet at the same time when the through hole is punched by the punching pin, and the punching of the through hole and the patterning can be performed in the same process, and the process required for processing can be reduced. Through holes and patterns can be synchronized to form accurate through holes and patterns without requiring accurate positioning of the green sheet.Furthermore, the pattern surface of the upper die is pressed against the green sheet to give a pattern. Since the punching pin exists in the through hole of the green sheet when the green sheet is present, the through hole having an accurate size is formed without the through hole being contracted and deformed by the pressing.

[Brief description of drawings]

FIG. 1 is a sectional view of an apparatus for carrying out the method of the present invention, FIG. 2 is a sectional view of a green sheet having through holes formed therein, and FIG.
The figure is a cross-sectional view of the above carrier plate, and FIGS. 4 (a) and 4 (b) are cross-sectional views and bottom views of another example of the above, where 1 is a carrier plate, 2 is a green sheet, 3 is a punch pin Reference numeral 4 is a through hole, 5 is a hollow portion, 6 is punching waste, 8 is an upper die, and 9 is a patterned surface.

Claims (1)

[Claims] 1. When punching a through hole by lowering a punching pin from above a green sheet of a cement-based building board placed on a carrier board, a punching is provided with a pattern surface on the lower surface and a hollow portion penetrating vertically. Using an upper mold in which pins are hung from the pattern surface, the upper mold is lowered onto the green sheet to press the pattern surface against the green sheet to form a pattern, and punch holes are used to punch through holes in the green sheet, A method for punching a through hole in a cement-based building board, characterized in that punching waste generated when the through hole is punched in the green sheet is discharged upward from the hollow portion of the punching pin.