JPH11257322A - Wood screw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a torque increase in a driver by forming a driving part whose diameter is enlarged from a tip end to a screw thread on an axial part tip end part, end forming an acute-angled blade in a screwing rotational direction on a circumferential surface of the driving part. SOLUTION: A screw thread 22 is formed around an axial part 21 of a wood screw 20, a driving part 23 whose diameter is enlarged is formed on a tip end part of the axial part 21 so as to bend from a tip end to an axial part 21, and a blade 24 having an acute angle in a rotational direction is formed around the driving part 23 in order to drive a screw in an object material. When a wood screw 20 is driven down into the object material by a driver, the wood screw 20 can be driven with a low resistance if the object material is made of sheet metal since the tip end part of the driving part 23 is formed in a sharply acute shape like an artillery shell shape. Also, if a conventional wall thickness part is generated on a penetrating hole formed on the sheet metal by a blade 24, the wall thickness part can be cut. Even if the wood screw 20 is completely screwed in the object material, the axial part 21 is fastened tightly on an edge part of the penetrating hole. It is thus possible to prevent increase of rotating resistance, and it is also possible to prevent a torque increase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wood screw used for an air motor or an electric automatic driver, and more particularly, to a method of driving a screw once into an object by an automatic driver and then performing a rotation operation to screw the screw. Wood screws.

[0002]

2. Description of the Related Art Conventionally, a so-called self-drilling screw (hereinafter referred to as SDS) has been known as a wood screw used for an air motor or an electric automatic driver device.
In this SDS, as shown in FIG. 8, the tip 2 of the screw 1 has the same diameter as the shaft 3, and the tip 2 is formed with a cutting blade 4 for driving a sheet metal or the like. This screw 1
The screw 1 can be screwed by bringing the cutting blade 4 into contact with an object such as a sheet metal and applying a rotational force in a direction of screwing into the head 5 of the screw 1.

However, with the SDS screw 1, the blade of the screwdriver cannot be driven into the head 5 of the screw 1 and the tip of the screw 1 cannot be driven into an object such as a sheet metal.
There is a problem that it takes time to penetrate the object by the cutting blade 4.

Therefore, as shown in FIG. 9, there is known a screw 6 in which a tip 7 is formed in a shell shape. The screw 6 is caused to collide the cutting edge of the driver of the automatic driver device with the head 8 of the screw 6 and penetrate an object 9 such as a metal plate (see FIG. 10), and then rotate the driver to remove the screw 5. It is screwed into the object 9.

[0005]

However, even with the wood screw 6 shown in FIG. 9, when the wood screw 6 is driven into the object 9 such as a sheet metal by the blade of a screwdriver, a burr is formed on the edge of the through hole of the sheet metal. A thick portion 10 is formed. Since the thick portion 10 fastens the shaft portion 11 of the wood screw 5, the wood screw 6
When the gypsum board 12 or the like is screwed, the shaft portion 11 of the wood screw 6 is overloaded with the gypsum board 12, while the gypsum board 12 is screwed. Since the gypsum board 12 is firmly held by the thick part 10 and cannot move freely, when the gypsum board 12 vibrates up and down due to an earthquake or the like, there is a concern that the bending force acts on the shaft part 11 repeatedly to break the shaft part 11.

The present invention has been made in view of such a problem. When an automatic screwdriver is used to screw a wood screw, the blade of the screwdriver is hit on the screw head and the tip of the screw is set on the object. When a screw is driven into an object such as a sheet metal, the occurrence of a thick portion is prevented to prevent an increase in the torque of the driver, and when the object vibrates up and down, the screw is screwed down. It is an object of the present invention to provide a wood screw that is hardly bent and applied to a shaft portion of the wood screw.

[0007]

According to a first aspect of the present invention, a wood screw is provided on a tip of a shank on which a thread is formed, from a tip to be screwed into an object to a thread. A driving part whose diameter increases is formed,
A blade having a sharp angle in the rotation direction at the time of screwing is formed on the peripheral surface of the driving portion.

According to the wood screw of the first aspect of the present invention, a driving portion whose diameter increases from the front end to the screw thread is formed at the tip of the wood screw, and a cutting blade is formed on the outer peripheral surface of the driving portion. When a wood screw is driven into an object such as a sheet metal by an automatic screwdriver, the thick part of the object is cut, and the force with which the shaft is tightened by the object is reduced, preventing an increase in driver torque when screwing. In addition, when the object vibrates up and down, the shaft portion of the screw is hardly bent and overloaded.

[0009]

Next, a wood screw according to a preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a side view of a wood screw according to the first embodiment, in which a screw thread 22 is formed around a shaft 21 of a wood screw 20, and the tip of the shaft 21 is formed from the tip. A driving portion 23 whose diameter increases so as to bend toward the shaft portion 21 is formed. A blade 24 having a sharp angle in the rotation direction when the screw is screwed into the object is formed on the peripheral surface of the driving portion 23. The head 25 of the wood screw 20 is formed with a cross-shaped groove 26 shown in FIGS.
A cross-shaped blade at the tip of a driver (not shown) is fitted into the cross-shaped groove 26. As shown in FIG. 4, the blade 24 of the driving portion 23 has a sharp edge in the direction in which the wood screw 20 is rotated and screwed in. In this embodiment, the blade 24 is formed at an intermediate portion of the driving portion 23.

When the wood screw 20 is driven into an object by an air motor or a driver of an electric automatic driver device, the tip of the driving portion 23 of the wood screw 20 is sharply pointed like a shell shape. Even with this, it is possible to drive with low resistance, and since the blade 24 is formed around the driven portion 23, even if a thick portion as in the past is formed in the through hole formed in the sheet metal or the like, this can be achieved. The thick part is cut by the blade 24. For this reason, even if the wood screw 20 is completely screwed into the object, it is possible to prevent the shaft portion 21 from being tightened tightly by the edge of the through hole, thereby preventing the rotational resistance of the driver from increasing, and preventing an increase in torque.

When the wood screw 20 is screwed into an object such as a sheet metal through a gypsum board or the like, the thick portion of the through hole of the sheet metal is cut by 24. Is the thickness in the thickness direction corresponding to the sheet metal. For this reason, the target object extends in the vertical direction, such as a wall material. Even if the wall material vibrates in the vertical direction due to an earthquake or vibration, the vertical movement of the shaft portion 21 is allowed. The bending load applied to the portion 21 can be reduced.

FIG. 5 shows a wood screw according to a second embodiment. In the wood screw 30, a driving portion 33 is formed at a tip end of a shaft portion 32 having a thread 31, and a pair of blades 34 which are sharp in a screwing direction are formed on an outer peripheral surface of the driving portion 33 as shown in FIG. 6. ing. This blade 34 has a driving portion 3
3 is formed over almost the entire area in the vertical direction. The head 35 of the wood screw 30 is formed in a hexagonal shape as shown in FIG. 7, and the head 35 is rotated by a socket wrench or the like and screwed into an object.

In this wood screw 30, the wood screw 2 shown in FIG.
As in the case of 0, since the hole to be driven by the blade 34 when screwing is cut and enters the object, a thick portion is formed in the through hole of the sheet metal even if the object is like a sheet metal. Is prevented, and the area of the portion for restraining the shaft portion 32 is small, so that an increase in the rotational torque of the driver can be prevented.
Therefore, even if the object vibrates in the lateral direction, the behavior of the shaft portion 32 is allowed, and the bending load applied to the shaft portion 32 can be reduced.

[0015]

According to the wood screw of the first aspect of the present invention, the spindle-shaped driving portion is formed at the tip of the wood screw, and the cutting edge is formed on the outer peripheral surface of the driving portion. When a wood screw is driven into an object such as a sheet metal, the thick part of the object is cut, and the force with which the shaft is tightened by the object is reduced. When the object vibrates up and down, the shaft portion of the screw is less likely to be bent and overloaded.

[Brief description of the drawings]

FIG. 1 is a side view of a wood screw according to a first embodiment of the present invention.

FIG. 2 is a plan view of the head of the wood screw shown in FIG. 1;

FIG. 3 is a sectional view of the wood screw head of FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV of FIG. 1;

FIG. 5 is a side view of a wood screw according to a second embodiment of the present invention.

FIG. 6 is a plan view of the head of the wood screw in FIG. 5;

FIG. 7 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 8 is a side view of a conventional SDS type screw.

FIG. 9 is a side view of a conventional wood screw.

FIG. 10 is an enlarged view of a thick portion generated when the wood screw shown in FIG. 9 is driven into a sheet metal.

[Explanation of symbols]

 Reference Signs List 20 Wood screw 21 Shaft part 22 Thread 23 Driving part 24 Blade

Claims (1)

[Claims] 1. A driving part whose diameter is increased from a tip to be screwed into an object to a thread is formed at a tip part of a shaft part where a thread is formed.
A wood screw characterized by forming a blade having a sharp angle in the rotation direction when screwing.