JPH0643532Y2 - Drill screw with stopper - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drill screw with a stopper suitable for attaching a soft member such as a corrugated plate or a heat insulating board used for a building roofing material or a wall material to a structure.

[0002]

2. Description of the Related Art Conventionally, as a drill screw with a stopper of this kind, a shank has a head portion provided with an engaging portion for a rotary tool, and the other end portion is continuous with the drill portion. It is known that a threaded portion and an annular stopper adjacent to the end of the threaded portion and having a diameter larger than the outer diameter of the threaded portion are provided, and the stopper is brought into contact with the structure to prevent overtightening. (See, for example, Japanese Utility Model Laid-Open No. 54-37764 and Japanese Utility Model Publication No. 2-27206).

[0003]

By the way, when attaching a corrugated plate or the like to a structure using such a drill screw with a stopper, if the structure is a thick plate such as an angle member, tapping resistance due to the screw portion is small. Therefore, the diameter of the pilot hole in the drill part should be as large as possible, while on the other hand, if the structure is a thin plate such as an aluminum sash, the diameter of the pilot hole in the drill part should be small, and the screw part should be tightened so that it spreads out. Is being prevented. Therefore, even with the same screw diameter,
It is necessary to change the diameter of the drill part for thick plates and thin plates,
Variety increased and inventory management was difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drill screw with a stopper, which has one kind of diameter for a thick plate and can be used for a thin plate.

[0005]

In order to achieve the above object, a drill screw with a stopper according to the present invention comprises a straight screw portion in which the screw portion taps into a prepared hole formed in the drill portion, Consisting of a straight thread portion and a taper thread portion whose diameter gradually increases toward the annular stopper, the maximum thread root diameter of the taper thread portion adjacent to the annular stopper is smaller than the diameter of the drill portion. It is characterized in that the outer diameter is set to be large and smaller than the outer diameter of the annular stopper.

[0006]

With the above construction, when used for a thick plate, after the straight screw portion is screwed into the prepared hole formed by the drill portion with a small tapping resistance, the screwing resistance is gradually increased at the taper screw portion. As a result, the stopper function works and the impact load due to the annular stopper coming into contact with the structure can be alleviated or avoided.
On the other hand, when used for a thin plate, the straight screw part passes with a slight tapping resistance with respect to the prepared hole drilled by the drill part, and the taper screw part radially pushes the peripheral part of the prepared hole. It is screwed in while being expanded, and idling due to over-tightening is prevented by the cooperation of the taper screw portion and the annular stopper.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a drill screw with a stopper according to the present invention. The drill screw 1 has a hexagonal head 3 at one end of an elongated shank 2 and a drill portion 4 at the other end.
And a configuration in which a threaded portion 5 continuous with the drill portion 4 and an annular stopper 6 adjacent to the end of the threaded portion 5 and having a diameter larger than the outer diameter of the threaded portion 5 are provided as a conventional drill screw with a stopper. Although the same, it is characterized by the structure of the screw portion 5.

That is, the threaded portion 5 is continuous with the straight threaded portion 7 that taps into the prepared hole projecting from the drill 4 and the straight threaded portion 7, and the diameter gradually increases toward the annular stopper 6. The taper screw portion 8 and the taper screw portion 8 adjacent to the annular stopper 6 have a root diameter d of the maximum thread 8a larger than the diameter C of the drill portion 4 and an outer diameter D larger than the outer diameter F of the annular stopper 6. It is configured to be small. The outer diameter of the straight screw portion 7 is set to be slightly larger than the diameter C of the drill portion 4 to reduce the tapping resistance for the prepared hole drilled by the drill portion 4.

FIG. 2 shows a usage example of the drill screw 1 with a stopper constructed as described above.

When the drill screw 1 is attached and fixed to the structure of the thick plate 11, the straight screw portion 7 is screwed into the prepared hole formed by the drill portion 4 with a small tapping resistance, and then the taper screw portion 8 is used. The screwing resistance gradually increases and the stopper function works, and it stops before contacting the annular stopper 6, or even when it stops by contacting the annular stopper 6, it abuts without applying a large impact load as in the conventional case, It is firmly and surely fixed to the thick plate 11.

On the other hand, when mounting and fixing to a thin plate 12 such as an aluminum sash, after the straight screw portion 7 passes through the prepared hole made by the drill portion 4 with a slight tapping resistance, the taper screw portion 8 becomes the prepared hole. The peripheral portion is expanded and screwed into the thin plate 12 in the vicinity of the maximum screw thread 8a, and the annular stopper 6 abuts against the thin plate 12, and the maximum screw thread 8a of the taper screw portion 8 and the annular stopper 6 cooperate with each other. , Around the hole due to over-tightening is prevented, and it is firmly and securely fixed.

[0013]

As described above, the drill screw with a stopper according to the present invention can use one type of screw for both thick and thin plates, and is very convenient to use and handle. It is also advantageous for inventory management.

[Brief description of drawings]

FIG. 1 is a front view of a drill screw with a stopper according to the present invention.

FIG. 2 is an enlarged front view of a main part showing the same usage state.

[Explanation of symbols]

 1 Drill screw with stopper 2 Shank 3 Head 4 Drill part 5 Screw part 6 Annular stopper 7 Straight screw part 8 Tapered screw part 8a Maximum screw thread

Claims (1)

[Scope of utility model registration request] 1. A shank having a head portion provided with an engaging portion for a rotary tool at one end thereof, a drill portion at the other end, a screw portion continuous with the drill portion, and an end of the screw portion. And a stopper-equipped drill screw provided with an annular stopper having a diameter larger than the outer diameter of the threaded portion, wherein the threaded portion is a straight threaded portion that taps into a prepared hole formed in the drilled portion, and the straight threaded portion. Continuing to the portion, consisting of a taper screw portion whose diameter gradually increases toward the annular stopper, the root diameter of the maximum thread of the taper screw portion adjacent to the annular stopper is larger than the diameter of the drill portion, A drill screw with a stopper having an outer diameter smaller than that of the annular stopper.