JPH10159821A - Drilling screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drilling screw by which a gypsum board can be threadedly fixed to a lightweight channel steel by means of a driving-type thread fastener. SOLUTION: A drilling screw 1 is formed in such a way that the diameter thereof is reduced from the parallel thread part 4 on the head side through the intermediates taper thread part 5, and that it is formed in a stepped shape from a small-diameter parallel thread part 6 up to the forefront end taper thread part 7. When driven both to a gypsum board and to a lightweight channel steel by a driving-type thread fastener, the forefront end taper thread part 7 penetrates through the steel sheet. Since the forefront end and the small- diameter parallel thread part are small in diameter, the steel sheet is hardly subjected to deformation. In the turning stroke after driven, the parallel thread part 4 is screwed into the lightweight channel steel for combining the gypsum board with the lightweight channel steel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a drilling screw, and more particularly to a drilling screw for fixing a gypsum board to a thin metal plate.

[0002]

2. Description of the Related Art The applicant of the present invention has disclosed a method of forming a 0.5 mm
Alternatively, a drilling screw suitable for screwing work for fixing a gypsum board to a lightweight channel steel having a thickness of 0.8 mm has been proposed (Japanese Patent Application No. 7-21780). The purpose of the drilling screw is to improve the efficiency of the screw tightening operation by enabling the gypsum board screwing operation by the driving-type screw tightening machine that has a shorter stroke time than the power screw tightening machine that only rotates.

[0003] That is, when a gypsum board screwing operation is performed by a conventional drilling screw and a driving screw driver, the previously tightened drilling screw is loosened by the impact of the next drilling screw driving or buried in the gypsum board. Thus, there was a problem that the load-bearing capacity was greatly reduced, and the gypsum board screwing operation by the driving screw tightening machine was impossible.

[0004] The drilling screw proposed by the present applicant is:
In order to solve the above-mentioned problem, the diameter is reduced from the large-diameter parallel screw portion having the trumpet head to the small-diameter parallel screw portion via the tapered screw portion, and a sharp tapered bit portion is formed at the tip of the small-diameter parallel screw portion. It is.

When a gypsum board is overlaid on a lightweight channel steel and the above-mentioned drilling screw is driven by a driver of a drive-type screw tightening machine, a tapered bit portion and a small-diameter parallel thread portion penetrate the gypsum board and the lightweight channel steel. Subsequently, the driver rotates the drilling screw, and the fine thread of the small-diameter parallel thread generates a thrust in the penetrating direction, and the tapered thread taps while expanding the through hole of the lightweight channel steel, and the parallel thread becomes Drilling screws are firmly fastened by penetrating the lightweight channel steel.

The above-mentioned drilling screw has a lighter channel compared to a conventional simple-shaped drilling screw in which a parallel thread portion and a tapered tip portion are continuously formed by forming a small-diameter parallel thread portion and a tapered bit portion. The deformation and vibration of the steel plate due to the impact when driving into steel were reduced, the deterioration of the fastening force and the load capacity was eliminated, and the installation by the driving type screw tightening machine, which was impossible with the conventional drilling screw, became possible.

However, when the drilling screw is screwed into the side plate portion of the lightweight channel steel, the side plate portion having a lower shape retention strength than the bottom portion is distorted by the impact of the drilling screw, or the gypsum board floats from the channel steel. May be. In such a case, the driving amount of the drilling screw into the channel steel is insufficient, and the small-diameter parallel screw portion may not penetrate the steel plate. In the rotation process, the driving force is not generated in the drilling screw and the drilling screw idles without being screwed. Will be.

Therefore, even in the case described above, there arises a technical problem to be solved so that the gypsum board and the channel steel can be securely fastened. The present invention solves the above problem. Aim.

[0009]

SUMMARY OF THE INVENTION The present invention proposes to achieve the above-mentioned object. The present invention is directed to a tapered tip threaded portion from a parallel threaded portion having a trumpet head at one end to an intermediate tapered threaded portion and a small-diameter parallel threaded portion. The present invention provides a drilling screw having a shape reaching

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, the drilling screw 1 has a parallel screw portion 4 at a lower portion of a trumpet head 3 provided with a cross hole 2, and the parallel screw portion 4 is connected to a small-diameter parallel screw portion 6 via an intermediate taper screw portion 5. The diameter is reduced, and a tapered tip thread portion 7 is formed via the small-diameter parallel thread portion 6.

The dimensions of the drilling screw 1 are 26.5 m in total length.
m, the outer diameter of the trumpet head 3 is 8 mm, the outer diameter of the parallel screw portion 4 is 3.5 mm, and the outer diameter of the small diameter parallel screw portion 6 is 2.5 mm. The double thread 8 continuous from the parallel thread 4 to the distal end of the tapered thread 7 has a taper angle of 15 degrees at the intermediate tapered thread 5 and a taper angle of 25 degrees at the tapered thread 7. The root diameter of the parallel screw part 4 is 2.4 mm, and the root diameter of the small diameter parallel screw part 6 is 1.7 mm.

A gypsum board (9.5 mm or 1 mm thick) is formed on a lightweight channel steel (sheet thickness 0.5 mm or 0.8 mm) by using a driving air driven screw tightening machine and a drilling screw 1.
2.5mm) when screwing, as shown in FIG.
The drilling screw 1 is driven into the gypsum board 9 with the coated paper by the driver of a driving-type air-driven screw tightening machine (not shown), and the tapered tip portion 7 drills a hole in the lightweight channel steel 10. As shown, the small diameter parallel screw portion 6
Stops while penetrating the lightweight channel steel 10. still,
11 is a board coated paper.

Further, as shown in FIG. 3, the driving amount may be insufficient due to the floating of the gypsum board or the deformation of the lightweight channel steel, and only the tip tapered thread portion 7 may penetrate the lightweight channel steel 10.

Subsequently, when the driver of the screw tightener fits into the cross hole of the trumpet head 3 and rotates the drilling screw 1, the screw fits into the lightweight channel steel 10 in either of the states shown in FIGS. Due to the thread 8 of the drilling screw 1 being engaged, a driving force is generated in the drilling screw 1 in the penetrating direction, and tapping is performed while expanding the through hole of the lightweight channel steel 10.

[0015] The parallel thread portion 4 is made of the lightweight channel steel 1.
0, the trumpet head 3 enters the gypsum board 9 and the propulsion resistance increases, and as shown in FIG. 4, the height of the trumpet head 3 becomes almost the same as the surface of the gypsum board 9 and stops rotating. I do.

[0016] As a result of an experiment in which the light-weight channel steel and the gypsum board were fastened by a driving-type screw tightening machine using the drilling screw 1, a relaxation torque value equal to or higher than the screw tightening result by the screw driver was 2.5 kgf.・ It was confirmed that the requirement of cm or more was satisfied. Also,
The amount by which the relaxation torque of the previously drilled screw is reduced by the driving vibration of the next drilling screw is also 1.4 kgf.
cm or less, and data equivalent to the drilling screw proposed by the applicant of the present application (Japanese Patent Application No. 7-21780) were obtained.
The same applies to the case where the coating paper 11 of the gypsum board 9 does not break or the screws do not float, and even if the driving amount is insufficient due to the deformation of the lightweight channel steel 10 or the floating of the gypsum board 9 shown in FIG. We can now conclude.

[0017]

As described above, the drilling screw according to the present invention has a small diameter at the tip and is less deformed and vibrated by the impact when driven into a lightweight channel steel. And lightweight channel steel can be fastened, and can be reliably fastened even when the amount of driving is insufficient due to the floating of the gypsum board, thereby contributing to prevention of occurrence of fastening failure and improvement of construction efficiency.

[Brief description of the drawings]

FIG. 1 shows a drilling screw of the present invention, wherein (a) is a plan view and (b) is a front view.

FIG. 2 is a sectional view showing a use state of the drilling screw of FIG. 1 and showing an example of a state at the time of driving.

FIG. 3 is a cross-sectional view showing a use state of the drilling screw of FIG. 1 and showing another example of a state at the time of driving.

FIG. 4 is a sectional view showing a state where the drilling screw is rotated and fastened from the state of FIG. 2 or FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling screw 2 Cross hole 3 Trumpet head 4 Parallel screw part 5 Intermediate taper screw part 6 Small diameter parallel screw part 7 Tip taper screw part 8 Double thread thread 9 Plaster board 10 Lightweight channel steel 11 Board coated paper

Claims (1)

[Claims] 1. A drilling screw having a shape extending from a parallel thread portion (4) having a trumpet head (3) at one end to a tip taper thread portion (7) through an intermediate taper thread portion (5) and a small-diameter parallel thread portion (6). .