JP6941320B2 - Anchor nails for ground laying materials and their nail making methods - Google Patents

Description

The present invention relates to an anchor nail for fixing a net-shaped, mat-shaped or sheet-shaped ground laying material laid on a slope (slope) or a flat surface (flat surface), and a method for making the nail.

In recent years, the purpose of early greening and protection of embankments and cut slopes and flat surfaces of roadsides and reclaimed land, embankment slopes of rivers and ponds and subsequent flat surfaces, collapsed slopes in mountains and slopes after excavation work, etc. As a result, a method of laying a vegetation sheet / mat holding seeds and fertilizer on the entire slope is being widely used. In addition, on these slopes and flat surfaces, weed-proof sheets are laid to prevent germination and growth of unnecessary grass seeds contained in the original soil, and tarpaulins are installed to prevent rainwater from penetrating into the ground. It may be laid.

However, these vegetation sheets / mats / nets, erosion prevention sheets / mats, weed-proof sheets, tarpaulins, etc. (hereinafter collectively referred to as ground laying materials) are laid on the ground such as slopes and flat surfaces. It needs to be fixed to the ground to keep it stable. As the fixing means, a method of driving an L-shaped anchor pin into the ground at a key point of a ground laying material has been widely used (for example, FIGS. 2, 4 and 5 of Patent Document 1 and FIGS. 3 and 3 of Patent Document 2). 8, 9). This L-shaped anchor pin is generally made of a mild steel wire having a wire diameter of 9 to 16 mm and a length of 200 to 400 mm. By hitting it with a hammer or the like and hitting it into the ground, the underground holding power is secured by its thickness and length.

Japanese Unexamined Patent Publication No. 2014-114651 Japanese Unexamined Patent Publication No. 2016-223265

However, while the conventional general-purpose L-shaped anchor pin is excellent in locking property to the ground laying material and holding force in the ground, it has a large unit weight (for example, the minimum size of wire diameter 9 mm and length 200 mm is about 110 g). There is a problem that the workability of driving is poor and the burden on the workers engaged in the construction is large. In other words, since it is necessary to fix the laid ground laying material at many places in order to keep it stable, the operator stops while moving on the slope in small steps while holding a large number of heavy anchor pins. In addition to securing a posture each time to perform the driving work, the driving work hits the base end of the anchor pin that is bent in an L shape, so the hitting point deviates from the underground traveling direction of the anchor pin and hits that much. In addition to the large loss of force, there were many cases where the upper side was bent and it became impossible to drive when the soil was hard or when the tip encountered gravel or rocks in the ground.

In view of the above circumstances, the present invention can secure a locking property to the ground laying material and a large underground holding force even if the unit weight is small as compared with the conventional general-purpose L-shaped anchor pin, and moreover, the driving workability can be secured. It is an object of the present invention to provide an anchor nail for a ground laying material which is excellent in the above and can significantly reduce the burden on an operator, and a nail making method for surely and easily manufacturing such an anchor nail.

If the means for achieving the above object is shown with reference numerals in the drawings, the anchor nails 1A and 1B for the ground laying material according to the invention of claim 1 have a diameter D: 6 to 9 mm and a length L: 150. A nail head 12 having a flange diameter (major axis) E1: 17 mm or more is provided on one end side of a nail shaft portion 11 having a diameter of about 300 mm, and the other end side of the nail shaft portion 11 has a tip 13 and a nail head. A plurality of ridges 2 are engraved in parallel on at least one of the front surface 12a side and the back surface 12b side of the portion 12, and a large number of rings arranged at at least the tip 13 side half of the nail shaft portion 11 at a constant pitch. The shape protrusion 4 or the screw portion 5 is provided, and the nail head 12 has an elliptical flange shape, and the ridge 2 is formed along the major axis E1 direction of the elliptical shape .

According to the second aspect of the present invention, in the anchor nails 1A and 1B for the ground laying material according to the first aspect, the ridge 2 has a height of 0.1 to 0.2 mm and a width of 0.20 to 0.40 mm. It has a structure.

The invention of claim 3 has a configuration in which the elliptical major axis of the anchor nails 1A and 1B for the ground laying material according to claim 1 or 2 is 20 mm or more.

The invention of claim 4 has the ridges 2 on the front surface 12a side and the back surface 12b side of the nail head 12 in the anchor nails 1A and 1B for the ground laying material according to any one of claims 1 to 3, and the surface surface 12a. The number of ridges 2 on the side is 10 to 20 at a constant pitch, and the number of ridges 2 on the back surface 12b is 8 to 12.

In the invention of claim 5, in the anchor nail 1A for the ground laying material according to any one of claims 1 to 4 , the ring-shaped protrusion 4 has a triangular chevron cross section, and the nail head side slope 4a in the triangular chevron cross section has a tip. The slope is steeper than the side slope 4b.

In the invention of claim 6, in the anchor nails 1A and 1B for the ground laying material according to any one of claims 1 to 5 , the ridge 2 on the back surface 12b side of the nail head 11 is an elliptical center portion in the minor axis direction. It is configured to be engraved on both sides except for the flat portion Z having a width substantially corresponding to the diameter D of the nail shaft portion 11 provided in the above.

The invention of claim 7 is the anchor nail 1A, 1B for the ground laying material according to any one of claims 1 to 6 , which protrudes higher than the ridge 2 on both sides of the nail head 12 on the back surface 12b side. It has a structure having a stop protrusion 3.
The anchor nails 1A and 1B for ground laying materials according to the invention of claim 8 have a flange diameter (major axis) E1: 17 mm on one end side of a nail shaft portion 11 having a diameter D: 6 to 9 mm and a length L: 150 to 300 mm. The nail head 12 having the above-mentioned flange shape is provided, the other end side of the nail shaft portion 11 forms a tip 13, and a plurality of protrusions 2 are engraved in parallel on the back surface 12b side of the nail head 12. At least on the tip 13 side half of the nail shaft portion 11, a large number of ring-shaped protrusions 4 or screw portions 5 arranged at a constant pitch are provided, and the ridge 2 on the back surface 12b side of the nail head 11 is elliptical. It is assumed that the nail shaft portion 11 provided at the center portion in the minor axis direction of the shape is engraved on both sides except for the flat portion Z having a width substantially corresponding to the diameter D of the nail shaft portion 11.

In the invention of claim 9, the metal wire 10 is fed to the cutting position, and the tip side of the metal wire 10 is partially projected by a pair of dies 6 on the front side of the cutting position. The nail head 12 is formed by striking the protruding tip of 10 with a punch 7 on the front side of the cutting position, and then the metal wire 10 is fed for a predetermined length and then cut by the cutting device 8 at the cutting position. In a nail making method in which an end portion is cut into a tip 13 shape, a die 6 and a punch 7 having a plurality of recesses 61 and 71 formed on at least one of the facing surfaces thereof are used, and the diameter of the metal wire rod 10 is 10. D: By striking with a punch 7 using a mild steel wire of 6 to 9 mm, the nail head 12 has an elliptical flange shape, and the ridge 2 is formed along the major axis E1 direction of the elliptical shape. , the molding surface 12a side and the back surface 12b side plurality of ridges 2 parallel engraved by Tsuba径17mm or more collar-shaped nail head 12 to at least one of the length of the Kugijiku 11 After cutting the nail shaft portion 11 into a tip 13 shape with a cutting end of 150 to 300 mm, a large number of ring-shaped protrusions 4 or screw portions 5 arranged at a constant pitch by rolling are formed at least on the tip 13 side half of the nail shaft portion 11. It is characterized by doing.
According to the invention of claim 10, the metal wire 10 is fed to the cutting position, and the tip end side of the metal wire 10 is partially projected by a pair of dies 6 on the front side of the cutting position. The nail head 12 is formed by striking the protruding tip of 10 with a punch 7 on the front side of the cutting position, and then the metal wire 10 is fed for a predetermined length and then cut by the cutting device 8 at the cutting position. In a nail making method in which an end portion is cut into a tip 13 shape, a die 6 and a punch 7 having a plurality of recesses 61 and 71 formed on at least one of the facing surfaces thereof are used, and the diameter of the metal wire rod 10 is 10. D: By striking with a punch 7 using a mild steel wire of 6 to 9 mm, the ridge 2 on the back surface 12b side of the nail head 11 has the diameter of the nail shaft 11 provided in the central portion in the minor axis direction of the oval shape. A nail head 12 having a flange diameter of 17 mm or more and having a plurality of protrusions 2 engraved in parallel on the back surface 12b side so as to be engraved on both sides except for the flat portion Z having a width substantially corresponding to D. Is formed, the length of the nail shaft portion 11 is 150 to 300 mm, the cut end portion is formed into a tip 13 shape, and after cutting, a large number of nail shaft portions 11 are arranged at a constant pitch by rolling at least on the tip 13 side half. It is characterized in that the ring-shaped protrusion 4 or the screw portion 5 of the above is formed.

Next, the effects of the present invention will be specifically described with reference to the drawings. According to the anchor nails 1A and 1B for ground laying materials according to the inventions of claims 1 and 8 , a nail shape having a large flange diameter of 17 mm or more is provided on one end side of a nail shaft portion 11 having a specific diameter D and length L. Since it is a peculiar form having a nail head 12 and a large number of ring-shaped protrusions 4 or screw portions 5 arranged at a constant pitch at least on the tip 13 side half of the nail shaft portion 11, it is a conventional general-purpose anchor. Although the unit weight is smaller than that of the pin, the nail head 12 can sufficiently secure the locking property of the ground laying material (vegetation mat M) and the nail shaft 11 can sufficiently secure the underground holding force. Since the point of impact when driving into the nail matches the direction of travel of the nail in the ground, there is no loss of striking force, and even if the soil is hard or the tip encounters gravel or rocks in the ground, the shaft portion 11 It can be rushed in, has excellent driving workability, and can significantly reduce the labor burden on workers engaged in construction. The plurality of ridges 2 engraved on at least one of the front surface side 12a and the back surface side 12b of the nail head 12 are hit by the punch 7 of the metal wire rod 10 corresponding to the nail shaft portion 12 in nail making. It is necessary to form the nail head 12 having a large collar diameter. Further, in the anchor nails 1A and 1B for the ground laying material according to the invention of claim 1, the nail head 12 has an elliptical flange shape, and the ridges 2 are formed along the elliptical major axis E1 direction. Therefore, the metal material can be easily spread along the ridges 2 during nail making, and thus a nail head 12 having a large major axis E1 can be reliably manufactured. On the other hand, in the anchor nails 1A and 1B for the ground laying material according to the invention of claim 8, the ridges 2 on the back surface 12b side of the nail head 11 are engraved on both sides except the flat portion Z in the central portion. There is an advantage that cracks can be avoided due to stress concentration on the die 6 side during nail making.

The anchor nails 1A and 1B for ground laying materials according to the invention of claim 2 can be reliably manufactured to include a nail head 12 having a large flange diameter because the height and width of the groove 2 are within a specific range.

Since the anchor nails 1A and 1B for the ground laying material according to the invention of claim 3 have a nail head 12 having an elliptical major axis of 20 mm or more, the locking property of the ground laying material (vegetation mat M) is particularly high. It will be excellent.

The anchor nails 1A and 1B for ground laying materials according to the invention of claim 4 have ridges 2 on the front surface side 12a and the back surface side 12b of the nail head 12, and the ridges 2 on the front surface side 12a and the back surface side 12b are formed. With a specific number and arrangement, it is possible to more reliably manufacture a nail having a collar-shaped nail head 12 having a large collar diameter.

In the anchor nail 1A for a ground laying material according to the invention of claim 5 , the ring-shaped protrusion 4 has a triangular chevron shape in cross section, and the nail head side slope 4a has a steeper slope than the tip side slope 4b. The resistance is small and it is easy to drive in, but the large resistance acts in the pulling direction, so it has excellent underground holding power.

The anchor nails 1A and 1B for the ground laying material according to the invention of claim 6 are made by engraving the ridges 2 on the back surface 12b side of the nail head 11 on both sides except the flat portion Z in the central portion. There is an advantage that cracks can be avoided in the stress concentration on the die 6 side at the time.

The anchor nails 1A and 1B for the ground laying material according to the invention of claim 7 have locking protrusions 3 protruding higher than the ridges 2 on both side surfaces of the nail head 12 on the back surface side 12a, and thus the ground laying material. There is an advantage that the locking property with respect to is further improved.

According to the method for making anchor nails for ground laying materials according to the inventions of claims 9 and 10 , a plurality of protrusions 2 are engraved in parallel on at least one of the front surface side 12a and the back surface side 12b, and the collar diameter is 17 mm. Anchor nails for ground laying materials having the above-mentioned elliptical nail head 12 and having a nail shaft portion 11 having a diameter of 6 to 9 mm can be stably manufactured. Further, according to the invention of claim 9, since the collar shape of the nail head 12 is elliptical and the ridge 2 is formed along the major axis E1 direction of the ellipse, a metal material is used at the time of nail making. Is easy to spread along the ridge 2, so that a nail head 12 having a large major axis E1 can be reliably manufactured. On the other hand, according to the invention of claim 10, the ridges 2 on the back surface 12b side of the nail head 11 are engraved on both sides except the flat portion Z in the central portion, so that the stress on the die 6 side during nail making is obtained. There is an advantage that cracks can be avoided in concentration.

Anchor nails for ground laying materials according to the first embodiment of the present invention are shown, (a) is a side view, (b) is a front view of a nail head, and (c) is an arrow of the XX line of (a). It is a sectional view. The formed portion of the ring-shaped protrusion on the nail shaft portion of the anchor nail for the ground laying material is enlarged and shown, (a) is a side view, and (b) is a longitudinal side view. It is a side view of the anchor nail for the ground laying material which concerns on the 2nd Embodiment of this invention. It is a schematic vertical sectional view which shows the fixed state to the ground of the vegetation mat by the anchor nail for the ground laying material which concerns on this invention. It is a nail making process diagram which shows typically the nail making method which concerns on this invention. The nail-making operations in the same nail-making method are shown in sequence. It is a side view. A die used for forming a nail head in the same nail operation is shown, (a) is a plan view, and (b) is a cross-sectional view taken along the line YY of (a). A punch used for forming a nail head in the same nail operation is shown, (a) is a plan view, and (b) is a cross-sectional view taken along the line ZZ of (a). The rolling operation of the ring-shaped protrusion of the nail shaft in the same nail manufacturing method is shown. It is a side view of each stage.

Hereinafter, the anchor nail for the ground laying material and the method for producing the anchor nail according to the embodiment of the present invention will be specifically described with reference to the drawings.

As shown in FIGS. 1 (a) to 1 (c), the anchor nail 1A for the ground laying material of the first embodiment has an elliptical collar-shaped nail head on one end side of the round shaft-shaped nail shaft portion 11. It has a portion 12, and the other end side of the nail shaft portion 11 forms a tip 13. Reference numeral 11a is a diameter-expanded portion that shifts from one end side of the nail shaft portion 11 to the nail head portion 12. The nail head 12 has a plurality of (11 in the figure) ridges 2 engraved in parallel on the front surface 12a side along the major axis E1 direction at a constant pitch, and the nail shaft 12 is also engraved on the back surface 12b side. Except for the central region Z having a width corresponding to the diameter D of the portion 11, a plurality of ridges 2 (4 on each side in the figure) along the major axis E1 direction are engraved in parallel on both sides at a constant pitch. Further, a large number of ring-shaped protrusions 4 arranged at a constant pitch are formed on the substantially half portion of the nail shaft portion 11 on the tip 13 side, while both side portions in the minor axis E2 direction on the back surface 12b side of the nail head portion 12. A ridge 3 is formed in the center of the ridge 2 along the major axis E1 direction.

Here, the nail shaft portion 11 of the anchor nail 1A has a diameter D: 6 to 9 mm and a length L: 150 to 300 mm. If the diameter D is too large or the length L is too long, the single weight will be excessive. Be strong. On the contrary, if the diameter D is too small or the length L is too short, the underground holding force becomes insufficient.

Further, the nail head 12 of the anchor nail 1A is not limited to the elliptical shape illustrated by the collar shape and may be circular, but the flange diameter (major diameter E1 in the illustrated elliptical shape) is 17 mm or more. If the collar diameter is less than 17 mm, a sufficient fixing force cannot be obtained due to insufficient contact width with the ground laying material. In particular, it is recommended that the major axis E1 of the illustrated elliptical nail head 12 is 20 mm or more. The minor axis E2 of the elliptical nail head 12 is not particularly limited, but is usually in the range of 17 to 19 mm due to the restrictions on nail making. The thickness of the nail head 12 is also not particularly limited, but is preferably in the range of 1.5 to 2.5 mm in terms of nail making property and mechanical strength.

Regarding the ridges 2 on the front surface 12a side and the back surface 12b side of the nail head 12, the height of each of the ridges 2 is preferably in the range of 0.05 to 0.30 mm and the width is preferably in the range of 0.25 to 0.40 mm. If the depth and width are out of the above range, it becomes difficult to form a large elliptical nail head 12 having a major axis E1: 20 mm or more. Further, the number of ridges 2 corresponds to the range of 10 to 20 on the front surface 12a side of the nail head 12 and the diameter D of the nail shaft 11 on the back surface 12b side in order to perform stable nail making. It is preferable to have a total of 8 to 12 nails on both sides excluding the flat portion Z in the center of the width.

Regarding the locking projection 3 on the back surface 12b side of the nail head 12, the amount of protrusion from the back surface 12b shall be 0.5 to 1.0 mm, the length shall be 3 to 10 mm, and the width shall be 0.3 to 0.8 mm. However, if the protrusion amount, length and width are too small, sufficient locking property with respect to the ground laying material cannot be secured, and conversely, if the protrusion amount, length and width are too large, a nail head 12 having a large flange diameter can be reliably formed at the time of nail making. It will be difficult.

As shown in FIGS. 2A and 2B, each ring-shaped protrusion 4 of the nail shaft portion 11 has a triangular chevron cross section, and the slope 4a on the nail head side has a steeper slope than the slope 4b on the tip side. ing. The valley between the adjacent ring-shaped protrusions 4 and 4 is lower than the blank surface of the nail shaft portion 11.

In the anchor nail 1B for the ground laying material of the second embodiment, the surface of the majority portion of the nail shaft portion 11 on the tip 13 side forms the screw portion 5, but other than that, the anchor nail 1B for the ground laying material of the first embodiment described above. Since it is exactly the same as the anchor nail 1A, the description of the form of the nail head 12 and the dimensions of each part will be omitted. Thus, in the screw portion 5 of the anchor nail 1B, the ridge portion 5a is generally higher and the valley portion 5b is lower than the blank surface of the nail shaft portion 11.

FIG. 4 illustrates a fixed form of the vegetation mat M by the anchor nail for the ground laying material of the present invention. Hereinafter, the anchor nails of the present invention including the anchor nails 1A and 1B of the first and second embodiments will be collectively referred to as an anchor nail 1 for a ground laying material. The vegetation mat M to be applied is composed of a mat-shaped embankment portion t, a polyethylene net n covering the mat-shaped embankment portion t, and fertilizer bags b arranged at substantially regular intervals along the inclination direction, and each fertilizer bag b is composed of. It consists of a long tubular object that is continuous in the substantially horizontal direction, and is laid as a whole from the top surface S1 of the embankment portion S to be protected to the slope or the flat surface S2 that follows the slope. Then, in each of the fertilizer bag b portions of the upper and lower plurality of stages of the vegetation mat M, the anchor nail 1 for the ground laying material is used, and the fertilizer bag b is penetrated from above the net n to the top surface S1 and the slope. By driving into the embankment portion S perpendicularly to the flat surface S2, the vegetation mat M is fixed to the embankment portion S, and each fertilizer bag b is fixed at a required position in the vegetation mat M.

In the fixing of the vegetation mat M by the anchor nail 1 for the ground laying material described above, since the flange diameter of the flange-shaped nail head 12 in the anchor nail 1 is as large as 17 mm or more, the locking property to the vegetation mat M is sufficiently sufficient. A large number of ring-shaped protrusions 4 or screw portions 5 which can be secured, the nail shaft portion 11 has a diameter D: 6 to 9 mm, a length L: 150 to 300 mm, and are arranged at a constant pitch on the tip 13 side half. Since it has a large underground holding force, there is no concern that the nail head 12 will come off the net n or the anchor nail 1 itself will come out of the filling portion S even if external forces in various directions are applied to the laid vegetation mat M. The vegetation mat M can be maintained in a stable laid state until the soil on the top surface S1 and the ground S2 is irreversibly strengthened by rooting due to the growth of vegetation from the tension turf portion t.

On the other hand, since the anchor nail 1 for the ground laying material is thinner and shorter than the conventional general-purpose anchor pin, the unit weight is small. The carrying load is small for the worker, and since the hitting point when driving into the ground coincides with the underground traveling direction of the nail, there is no loss of striking force, so the soil is hard or the tip is underground. Even if the shaft portion 11 is rushed into the shaft even if it encounters gravel or rocks, the workability of driving is excellent, so that the labor burden on the operator can be significantly reduced.

Incidentally, the weight of the conventional general-purpose L-shaped mild steel anchor pin having a wire diameter of 9 mm and a length of 200 mm was 109.4 g, whereas the weight of the mild steel anchor nail 1A of the first and second embodiments was 109.4 g. , 1B, the major axis E1 of the elliptical nail head 12 is 21 mm, the blank diameter D of the nail shaft 11 is 7 mm, and the length L is 200 mm, both of which weigh 62.4 g, that is, about 57% of the anchor pin. It was the weight of.

As such an anchor nail 1 for a ground laying material, one having a large number of ring-shaped protrusions 4 arranged on the nail shaft portion 11 at a constant pitch as in the first embodiment, and a nail shaft as in the second embodiment. Any one having a screw portion 5 in the portion 11 can be used, but the former one having a ring-shaped protrusion 4 is preferable because it is superior in underground holding power. In particular, in a form such as the anchor nail 1A of the first embodiment, in which the nail head side slope 4a in the triangular chevron cross section of the ring-shaped protrusion 4 has a steeper slope than the tip side slope 4b, the resistance in the driving direction is small. While it is easy to insert, it has the advantage of being excellent in underground holding force because a large resistance acts in the pulling direction. Further, like the anchor nails 1A and 1B of the first and second embodiments, those having locking projections 3 along the major axis E1 direction on both sides of the back surface side 12a of the elliptical nail head 12 in the minor axis E2 direction. Then, there is an advantage that the locking property to the ground laying material is further improved.

In the fixing of the vegetation mat M illustrated in FIG. 4, the anchor nail 1 is driven into each fertilizer bag b portion, but it goes without saying that the anchor nail 1 may be driven into a position separated from the fertilizer bag b. Further, the ground laying material to which the anchor nail 1 of the present invention is applied is not limited to the illustrated vegetation mat M, but also a weed-proof sheet for preventing germination and growth of unnecessary grass seeds contained in the original soil, and ground. It includes those laid on the ground for various purposes, such as waterproof sheets for suppressing the penetration of rainwater into the inside.

Next, a nail-making method for the anchor nail 1 for the ground laying material of the present invention will be described. In the nail making process diagram shown in FIG. 5, reference numeral 10 denotes a metal wire made of a nail material, which is unwound around the wire frame 100 and fed to the nail making machine N. In the nail making machine N, the metal wire 10 is straightened from a curved shape to a linear shape through a plurality of rollers 101a of the straightening device 101, and then intermittently sent to the nail making portion 103 via the wire sending device 102. In the nail making portion 103, a holding device 60 composed of a pair of dies 6 and 6 that can be opened and closed sequentially from the upstream side in the feeding direction of the metal wire 10, a cutting device 80 equipped with a pair of tooth bodies 8 and 8, and a punch 7 A punching device 70 equipped with the above is arranged, and a nail blank 1a is produced from the metal wire 10. Then, the nail blank 1a produced by the nail making portion 103 is ring-processed or screw-processed in the rolling mill R to become the ground laying material anchor nail 1 of the present invention.

Explaining the operation of the nail making portion 103 in detail, first, as shown in FIG. 6A, the metal wire 10 is squeezed from both sides by closing the pair of tooth bodies 8 and 8 of the cutting device 80 from the open state. It is cut so that it is sandwiched and squeezed. Subsequently, as shown in FIG. 6B, both dies 6 and 6 of the sandwiching device 60 are closed with the opening of both tooth bodies 8 and 8, and the metal wire 10 is sandwiched between the dies 6 and 6. The punch 7 of the punching device 70 moves forward and hits the cut end portion 10a of the metal wire 10 protruding from the tip surfaces of both dies 6 and 6 only once to form the nail head 11. Next, as shown in FIG. 6 (c), both dies 6 and 6 are opened, and as the punch 7 retracts, the metal wire 10 having the nail head 12 formed at the tip thereof is connected by the wire transmission device 102 (see FIG. 5). It is sent for the specified length. Then, as shown in FIG. 6D, the tooth bodies 8 and 8 of the cutting device 80 are closed to cut the metal wire 10, and at the same time, the tip 13 of the nail blank 1a is formed, and the cut end side is the nail blank. It falls as 1a.

Therefore, in the nail making method of the present invention, it is necessary to form a large elliptical nail head 12 having a flange diameter of 17 mm or more like the anchor nails 1A and 1B of the first and second embodiments described above. be. However, with general specifications for both dies 6, 6 and punch 7, that is, those with flat contact surfaces with each other, when the blank diameter D of the nail shaft portion 11 is about 7 mm, the flange diameter is 17 mm or more. It has been found that the nail head 12 of the above cannot be formed. That is, the formation of the nail head 12 by punching is usually due to the metal material forming the cut end portion 10a of the metal wire 10 protruding from the tip surfaces of both dies 6 and 6 spreading to the periphery by striking pressure. With the striking force of, the nail head 12 having a large diameter cannot be obtained due to insufficient spreading, but when the striking force is increased, the die 6 and the punch 7 are damaged.

Under these circumstances, in order to realize a nail head 12 having a sufficient diameter, the present inventors variously change the form of the contact surface between the die 6 and the punch 7 and perform an enormous molding test. Repeated trial and error. In the process, in order to facilitate the spread and movement of the metal material of the metal wire 10 to the periphery when punching to form the nail head 12, the morphology of the contact surface of the die 6 and the punch 7 was diligently examined. As a result, by using a die 6 and a punch 7 in which a plurality of recesses 61 and 71 are formed in parallel on at least one of the facing surfaces thereof, the metal material of the metal wire 10 can be easily spread and moved. Therefore, it has been clarified that the anchor nail 1 for the ground laying material of the present invention can be stably mass-produced without causing damage to the die 6 and the punch 7.

Further, from a new idea that the nail head 12 is made elliptical instead of circular and the locking width with respect to the ground laying material is secured on the major axis side thereof, a concave groove formed on at least one of the facing surfaces of the die 6 and the punch 7. By shaping 61 and 71 along the elliptical major axis E1, we succeeded in forming an elliptical nail head 12 having a major axis E1 of 20 mm or more. 7 and 8 illustrate the dies 6 and the punch 7 used in one embodiment of the method for making anchor nails for ground laying materials according to the present invention.

In FIGS. 7A and 7B, a pair of both dies 6 and 6 are shown in a closed state, and a round hole 6a for sandwiching a metal wire 10 (see FIG. 6) is formed between the two dies 6 and 6. A diameter-expanded portion 6b corresponding to the diameter-expanded portion 11a of the anchor nail 1 [see FIGS. 1 (a) and 3] is provided at the tip-side opening edge of the round hole 6a. Then, on the tip surfaces of both dies 6 and 6 (opposite surfaces with the punch 7), on both sides except the central portion of the width corresponding to the diameter of the round hole 6a, in the direction of the junction surface of both dies 6 and 6. A plurality of recesses 61 (four on each side in the figure) are formed at a constant pitch, and recesses 62 slightly wider and deeper than the recesses 61 are joined to the center of the outermost recesses 61. It is formed along the plane direction.

The punches 7 shown in FIGS. 8 (a) and 8 (b) are columnar, and a plurality of punches (11 in the figure) along the elliptical major axis direction, that is, the conjunction surface direction of both dies 6 and 6 are formed on the entire end surface thereof. The recesses 71 are formed at a constant pitch.

Then, in the nail making shown in FIGS. 6A to 6D described above, the ridges 61 and 71 of both the dies 6 and 6 shown in FIG. 7 and the punch 7 shown in FIG. 8 are oriented in the same direction. When used in this arrangement, the nail head 12 formed by punching becomes elliptical, and the front and back surfaces thereof correspond to the respective recesses 61 and 71, as shown in FIGS. 1 (b) and 1 (c). A plurality of ridges 2 along the major axis E1 direction are engraved in parallel, and locking protrusions 3 corresponding to the recesses 62 of each die 6 are formed at both side positions of the back surface of the nail head 12. become.

The plurality of recesses 61 and 71 along the major axis direction of the ellipse may be provided on either side of the punch 7 and both dies 6 and 6, but the punch 7 and both dies 6 may be provided as illustrated. It is preferable to provide them on both sides of, 6 because the metal material of the metal wire 10 is more easily spread and moved during punching. Further, as the metal wire 10, a mild steel wire is generally used.

Thus, the nail blank 1a provided with the large elliptical nail head 12 is subjected to ring processing or screw processing in the rolling mill R as described above to obtain the anchor nail 1 for the ground laying material of the present invention. 9 (a) to 9 (d) exemplify the ring processing by the rolling mill R in the order of processes. In this ring processing, first, as shown in FIG. 9A, the nail blank 1a is sequentially extruded from the tip of the blank supply guide 104 by the feed arrow 105, and is in a vertical state between the pair of ring forming plates 9a and 9b arranged in parallel. Insert with. The plates 9a and 9b for forming both rings are each provided with a basis weight on the facing surfaces thereof. One plate 9a is on the fixed side and the other plate 9b is on the movable side with respect to the plate 9a on the fixed side. The inserted nail blank 1a is sandwiched at a position where the movable plate 9b is retracted to the maximum. Next, at the same time as the feed arrow 105 retracts, as shown in FIG. 9B, the movable plate 9b starts to move forward, and the nail blank 1a rotates between the two plates 9a and 9b accordingly. In the process of advancing, the basis weight pattern on the facing surfaces of the plates 9a and 9b is transferred to the nail shaft portion 11 of the nail blank 1a. Then, when the rotating nail blank 1a reaches the end of the fixed side plate 9a as shown in FIG. 9C, the movable side plate 9b further advances as shown in FIG. 9D. An anchor nail 1A for a ground laying material having a large number of ring-shaped protrusions 4 on a substantially half portion of the nail shaft portion 11 on the tip 13 side is released.

In addition, like the anchor nail 1B for the ground laying material of the second embodiment, the nail shaft portion 11 having the screw portion 5 in the substantially half portion on the tip 13 side is for forming a pair of rings in the rolling mill R. Instead of the plates 9a and 9b, fixed-side and movable-side plates having screw-shaped basis weight processing on their facing surfaces may be used.

Next, the holding force and the driving property of the conventional general-purpose L-shaped anchor pin and the anchor nails 1A and 1B according to the first and second embodiments of the present invention described above were tested. The results are shown in Table 1 below along with the size and weight. All of the test anchors are manufactured using mild steel wire. Both the anchor nails 1A and 1B are provided with the nail heads 12 shown in FIGS. 1 (b) and 1 (c), and each of the ridges 2 has a width of 0.3 mm and a depth of 0.2 mm. In both tests, wood was used as an alternative because the properties of the soil to be driven vary greatly in the original soil. The test method is as follows.

[Holding power test]
After each anchoring tool was hammered vertically into a thick plate of SPF204 material to a depth of 100 mm, the force required for pulling out was measured as a holding force using a tensile tester. The ratio is a comparison with the holding force of the anchor pin as 100%.

[Drivability test]
Each anchor is held vertically on a thick plate of SPF204 material, and a cylindrical weight with a weight of about 2 kg and a diameter of 25 mm is dropped from a height of 1 m via a hollow rod for guidance to hit the top of each anchor. By the method, the amount of impact by 10 hits was examined. The ratio is a comparison in which the driving amount of the anchor pin is 100%.

As is clear from Table 1, the anchor nails 1A and 1B according to the present invention are lighter than the conventional general-purpose L-shaped anchor pin, but have a larger holding force than the anchor pin. It is also excellent in driving performance. The anchor pin was in a state where it could not be further driven because the upper side was bent by 10 hits in the driving property test.

1,1A, 1B Anchor nail for ground laying material 10 Metal wire 11 Nail shaft 12 Nail head 12a Front surface 12b Back surface 13 Tip 2 Convex 3 Locking protrusion 4 Ring-shaped protrusion 4a Nail head side slope 4b Tip side slope 5 Screw Part 6 Punch 61 Concave 7 Die 71 Concave 8 Cutting device D Nail shaft diameter (blank diameter)
E1 major diameter (brimmed diameter)
E2 short diameter Z flat part

Claims (10)

A nail shaft having a diameter of 6 to 9 mm and a length of 150 to 300 mm has a collar-shaped nail head having a collar diameter of 17 mm or more, and the other end of the nail shaft has a tip. A plurality of ridges are engraved in parallel on at least one of the front surface side and the back surface side of the nail shaft, and a large number of ring-shaped protrusions or screw portions arranged at a constant pitch are formed at least on the tip side half of the nail shaft portion. Provided ,
Anchor nail for ground laying material in which the collar shape of the nail head is elliptical and the ridges are formed along the major axis direction of the ellipse. The anchor nail for a ground laying material according to claim 1, wherein the ridge has a height of 0.05 to 0.30 mm and a width of 0.25 to 0.40 mm . The anchor nail for a ground laying material according to claim 1 or 2 , wherein the elliptical major axis is 20 mm or more. It has the ridge on the first surface and the second surface of the nail head, the surface side of the projections 10 to 20 present, according to any one of claims 1 to 3 back side of the ridge is 8 to 12 present Anchor nails for ground laying materials. The anchor nail for a ground laying material according to any one of claims 1 to 4 , wherein the ring-shaped protrusion has a triangular chevron shape in cross section, and the slope on the nail head side in the triangular chevron cross section is steeper than the slope on the tip side. Claims 1 to 5 are formed by engraving the ridges on the back surface side of the nail head on both sides except for a flat portion having a width substantially corresponding to the diameter of the nail shaft portion provided in the central portion in the minor axis direction of the ellipse. Anchor nails for ground laying materials described in any of. The anchor nail for a ground laying material according to any one of claims 1 to 6 , wherein the nail head has locking protrusions protruding higher than the protrusions on both sides on the back surface side. A nail shaft having a diameter of 6 to 9 mm and a length of 150 to 300 mm has a collar-shaped nail head having a collar diameter of 17 mm or more, and the other end of the nail shaft has a tip. A plurality of ridges are engraved in parallel on the back surface side of the nail shaft, and a large number of ring-shaped protrusions or screw portions arranged at a constant pitch are provided at least on the tip side half of the nail shaft portion.
The ridges on the back surface side of the nail head are anchors for ground laying materials, which are engraved on both sides except for a flat portion having a width substantially corresponding to the diameter of the nail shaft provided in the central portion in the minor axis direction of the ellipse. nail. The metal wire is fed to the cutting position, and the tip side of the metal wire is partially projected by a pair of dies on the front side of the cutting position, and the protruding tip of the metal wire is held on the front side of the cutting position. In the nail making method, the nail head is formed by striking with a punch in the above, and then the metal wire is fed to a predetermined length, and then the cut end is cut into a tip shape by a cutting device at the cutting position.
As the die and punch, a plurality of recesses formed in parallel on at least one of the facing surfaces of both are used, and a mild steel wire having a diameter of 6 to 9 mm is used as a metal wire and hit with a punch to hit the nail head. The nail shape is elliptical, and a plurality of ridges are engraved in parallel on at least one of the front side and the back side so that the ridges are formed along the major axis direction of the oval. A flange-shaped nail head of 17 mm or more is formed, the length of the nail shaft is 150 to 300 mm, the cut end is made into a tip shape, and after cutting, at least the tip side half of the nail shaft is fixed by rolling. A method for making anchor nails for ground laying materials, which comprises forming a large number of ring-shaped protrusions or screw portions arranged at a pitch. The metal wire is fed to the cutting position, and the tip side of the metal wire is partially projected by a pair of dies on the front side of the cutting position, and the protruding tip of the metal wire is held on the front side of the cutting position. In the nail making method, the nail head is formed by striking with a punch in the above, and then the metal wire is fed to a predetermined length, and then the cut end is cut into a tip shape by a cutting device at the cutting position.
As the die and punch, a plurality of recesses formed in parallel on at least one of the facing surfaces of both are used, and a mild steel wire having a diameter of 6 to 9 mm is used as a metal wire and the nail head is hit with a punch. Multiple protrusions on the back surface side so that the ridges on the back surface side are engraved on both sides except for the flat portion having a width substantially corresponding to the diameter of the nail shaft portion provided in the central portion in the minor axis direction of the elliptical shape. A nail head with a flange diameter of 17 mm or more in which strips are engraved in parallel is formed, the length of the nail shaft is 150 to 300 mm, the cut end is made into a tip shape, and then at least the nail shaft is cut. A method for making anchor nails for ground laying materials, which comprises forming a large number of ring-shaped protrusions or screw portions arranged at a constant pitch by rolling on the tip side half portion.

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