JPH0443614Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to nails, particularly nails suitable for fixing relatively fragile board materials such as particle boards and cement product boards, which have poor nail holding power, to wooden columns and the like.

Conventionally, when fixing cement-based boards with nails, it was difficult to maintain sufficient holding force when using ordinary straight nails, so spiral protrusions were often formed on the peripheral surface, known as screw nails. is used. However, even if such nails are used, especially when driving with an air gun, the driving speed of the nail is fast, so the nail cannot be expected to rotate according to the lead of the spiral protrusion during driving, and boards Since the nail is driven in such a manner as to destroy the inner surface of the peripheral wall of the guide hole to be drilled, there is a problem in that the desired fixing force, that is, the nail holding force cannot be achieved.

In order to solve the above-mentioned problems, this idea was developed by changing the shape of the nail shaft in various ways and repeating many experiments.The idea was to achieve an excellent holding force that is most suitable for fixing boards. This was completed by finding a shape of the shaft that could be provided with a band.

As shown in the illustrated embodiment, the inclination angle of the leading side flank 4a is adjusted in the lower part A from the middle in the length direction of the shaft part 1, which has a head part 2 and a tip part 3 on the upper and lower sides. A plurality of annular protrusions 4 having a serrated cross section with θ set to 50° or more are formed, and a holding force reinforcing portion 6 consisting of a group of many radial protrusions 5 long in the axial direction is provided on the upper portion B. A plurality of 6 are provided at predetermined intervals in the axial direction, and
In the holding reinforcement parts 6, 6, the height of the radial ridges 5 is gradually increased from the lower level to the upper level, and the diameter of the circle connecting the apexes is gradually increased. The nail is characterized in that the diameter of the lowermost radial projection 5 is slightly larger than the diameter of the uppermost annular projection 4.

In the illustrated embodiment, the annular protrusions 4 all have the same diameter, but the annular protrusions 4 may have larger diameters as they go higher. Further, a predetermined interval may be formed between the annular projections 4, 4 adjacent to each other in the upper and lower directions. The inclination angle θ of the leading side flank 4a of the annular projection 4 is formed to be 50° or more, and the trailing side flank 4
b is horizontal or facing the center line of shaft part 1 from 5 to
It is preferable to form it in a slightly downwardly inclined shape of about 10°.

The holding force reinforcing parts 6, 6, . . . each have a large number of radial protrusions 5, 5, . Each of these radial protrusions 5 has a triangular cross section, and each of the holding force reinforcement portions 6,
In No. 6..., the number is the same and they are arranged in a straight line parallel to the axis, but the heights in the cross-sectional shape are different. That is, as is clear from the comparison of the cross-sectional shapes of the individual holding force reinforcing parts 6, 6... shown in FIGS. 3 to 6 (excluding FIG. 4), the holding force of the plurality of The radial protrusions 5,
The height of the cross-sectional shape of 5... is made high. That is, the degree of outward protrusion is gradually increased. Therefore, each holding force reinforcement part 6,6
... is such that the apex angles of the radial protrusions 5, 5... gradually become smaller and the diameter of the circle connecting the apexes becomes gradually larger as one goes from the lower one to the higher one. There is. Moreover, the diameter of the lowermost radial protrusion 5 is formed to be slightly larger than the diameter of the uppermost annular projection 4.

Although it is preferable that the cross-sectional shape of the radial protrusions 5 be formed into a triangular shape as shown in the figure, the cross-sectional shape is not limited to this, and for example, the cross-sectional shape may be formed into a circular arc shape.

Since the nail according to this invention has the above-mentioned structure, for example, as shown in Fig. 7, a structurally relatively weak plate-like building material made of a cement product board or the like is attached to a wooden pillar or a frame. When used for fixing to a mating material such as wood, first, when driving the lower part A of the shaft part 1 into the plate-shaped building material A, the inclination angle θ of the advancing side flank 4a of the annular protrusion 4 is 50° or more. Because it is formed in a gentle taper shape, the annular protrusion 4 can be attached to the building material A without significantly destroying the building material A.
A circular guide hole corresponding to the diameter of is formed. Then, as the driving of the nail further progresses, the holding force reinforcing parts 6, 6, . At this time, first, the lowermost holding force reinforcing portion 5 having the radial protrusion 5 with a diameter slightly larger than the diameter of the hole enters the guide hole, and then the radial protrusion 5
Since the upper holding force reinforcing part 6 whose height is gradually increased enters the upper holding force reinforcing part 6, the upper holding force reinforcing part 6 is driven into the building material A with an expansion action that forcibly expands the guide hole. Therefore, in the driven state, each of the holding force reinforcement parts is firmly held inside the building material etc. in a state where it is strongly tightened from the surroundings.

On the other hand, the lower part A of the shaft part 1 is driven into a mating material such as wood, but in this driving state, due to the locking action of the annular protrusion 4, a large resistance force is generated exclusively against the force in the direction of nail removal. do. In particular, since the inclination angle θ of the advancing side flank 4a is set to 50° or more, it is possible to generate a much larger resistance against the force in the withdrawal direction than when the inclination angle θ is small.

As mentioned above, in the nail according to this invention, the lower part A of the shaft part 1 that enters into the mating material achieves an excellent retaining effect, while the upper part B
Even when the nail is driven into a structurally weak building material, the hole formed in the building material, that is, the structure of the peripheral wall facing the nail, is not destroyed and a good close contact is maintained. It is secured and mainly achieves an excellent retention effect on the building material. Therefore, as a result, the driving state is reliably maintained,
It can serve an excellent adhesion purpose.

[Brief explanation of drawings]

Fig. 1 is a front view of an embodiment of this invention, Fig. 2 is a longitudinal sectional view thereof, Figs. FIG. 7 is a sectional view of the device in use. 1...Shaft part, 2...Head part, 3...Point part, 4...
... annular projection, ... radial protrusion, 6 ... holding force reinforcement part.

Claims (1)

[Scope of utility model registration request] A plurality of serrated sections are provided in a portion A below the middle in the length direction of the shaft portion 1 having a head portion 2 and a tip portion 3 at the upper and lower sides, and exhibiting a serrated cross section with an inclination angle θ of 50° or more of the advancing side flank 4a. In the upper part B where the annular protrusion 4 is formed, a plurality of holding force reinforcing parts 6, 6 each consisting of a large number of groups of radial protrusions 5 that are long in the axial direction are provided at predetermined intervals in the axial direction, and In the holding force reinforcement parts 6, 6, the height of the radial protrusions 5 is gradually increased from the lower to the upper part, and the diameter of the circle connecting the apexes is gradually increased. A nail characterized in that the diameter of the lowermost radial protrusion 5 is slightly larger than the diameter of the uppermost annular protrusion 4.