JP6800819B2 - Die for drawing - Google Patents

Description

The present invention relates to dies, especially those used in drawing.
In the production of wire rods that require linearity, such as for construction, it is common to draw out using a drawing machine and a drawing machine.

FIG. 1 is a schematic view showing the entire structure of the drawing machine. Further, FIG. 2 is a cross-sectional view showing the structure around the die of the drawing machine at the time of use.

In FIG. 1, the drawing die 901 and the die holder 902 are drawn as a cross-sectional view, and the other structures are shown as a top view seen from above. Further, FIG. 1 shows a direction in which the drawing machine 903 pulls the material wire rod A-1 and the finished wire rod A-2. The material wire rod A-1 and the finished wire rod A-2 are collectively referred to as wire rod A.

The drawing machine 900 includes a drawing die 901, a die holder 902, a drawing machine 903, and a guide rail 904.

The drawing die 901 is a die for plastic deformation having a substantially cylindrical shape. A through hole through which the wire rod A to be drawn is passed is provided in the central shaft of this substantially cylindrical shape. The narrowest bearing portion 901b determines the shape and dimensions of the finished wire rod A-2 after molding. And across the bearing portion 901b approach portion 901a and the back relief part 901c, the fitting holes 901d exists.

When manufacturing the twist bar, the entire drawing die 901 is rotated around this substantially cylindrical central axis.

The approach portion 901a is a part of the drawing die 901 which is an entrance for drawing the material wire rod A-1 into the drawing die 901 and narrowing the outer diameter. The approach unit 901a converts the pulling force added by the drawing machine 903 into a compressive force. The die actually used may be provided with an entrance portion having a larger opening than the approach portion. However, in the present specification, the entrance portion is a design matter, and the description and the numbering on the drawings are omitted.

At least the approach portion 901a in contact with the material wire rod A-1 and the bearing portion 901b of the approach portion 901a are formed of cemented carbide. The material wire A-1 is plastically deformed by pressing it against the cemented carbide by drawing, and the cross-sectional area of the material wire A-1 is deformed to that of the finished wire A-2. The portion formed of this cemented carbide is referred to as the cemented carbide portion 901bh.

The bearing portion 901b is a portion of a drawing die 901 that determines the dimensions of the finished wire rod A-2.

The back relief portion 901c is a part of the die 901 tapered so as to be separated from the finished wire A-2 so as not to damage the surface of the finished wire A-2.

Fitting hole 901d is a fitting portion for fixing a die 901 into a die holder 902. Further, when the die holder 902 rotates the die 901 to produce the twisted bar driving force via the engaging hole 901d is transmitted to the die 901.

The die holder 902 is a holding portion for holding the drawing die 901 without losing the pulling force added by the drawing machine 903. Depending on the object, it is possible to manufacture a twist bar by rotating the drawing die 901 according to the position of the drawing machine 903.

The drawing machine 903 is a drawing machine in which the wire rod A is fixed by a carriage that is a part thereof, and the wire rod A after fixing is pulled to plastically deform the wire rod A.

The guide rail 904 is a guide rail for moving the drawing machine on a certain line or a drawing table including the guide rail.

When a steel material such as a rod-shaped material or a wire rod is drawn out by a die, a powdery solid lubricant is generally housed in a box 905 provided on the front side of the die, and the lubricant adheres to the wire rod A. This powdery lubricant becomes an oil film due to the processing heat generated by the approach portion 901a when the drawing machine 903 is pulled out. A powdery lubricant adheres to this oil film to form a lump. This lump becomes enlarged every time the drawing process is continued, and the supply of the lubricant to the surface of the material wire rod A-1 is hindered. As a result, it was considered that the surface of the finished wire rod A-2 was scratched.

In addition, when removing these lumps, it is necessary to temporarily stop the work, and as a result, a decrease in production amount is unavoidable. Especially when manufacturing a twist bar, this adverse effect is remarkable, which is one of the reasons why the manufacturing cost cannot be reduced.

Japanese Patent Application Laid-Open No. 2010-036228 (Prior Document 1) describes a technique of using a liquid lubricant instead of using a powder lubricant.

Japanese Patent Application Laid-Open No. 2010-036228

However, liquids are difficult to handle, and measures against liquid leakage and the like are required.

An object of the present invention is to provide a means for preventing the generation of a lump of lubricant as much as possible, reducing the time required for maintenance thereof as much as possible, and as a result, reducing the manufacturing cost of a wire rod having a polygonal cross section.

Another object of the present invention is to provide a wire mesh using the twist bar at an inexpensive price by using the twist bar with improved mass productivity described above.

The above and other objects and novel features of the present invention will become apparent from the description and accompanying drawings herein.

Twist bar according to the present invention has a generally polygonal cross section, and wherein at least one corner of said substantially polygonal form of the twist bars are rounded from the first drawing direction to the end, the twist bars The drawing die for forming is provided with a fitting portion for fixing to the die holder so as to rotate in the circumferential direction together with the die holder during the drawing process of the material wire, and the opening of the bearing portion of the die is omitted. It has a polygonal cross-sectional shape, the substantially polygonal shape is a polygon in which at least one corner of the base polygon is connected by an arc or a curved line, and the cross-sectional shape of the opening is of the material wire rod. It is the same along the pull-out direction .

With the die according to the present invention, it is possible to reduce the number of times that the work of removing the lump of the lubricant is frequently performed in the past. As a result, the number of wire rods produced can be increased and the manufacturing cost can be reduced.

It is a schematic diagram which shows the whole structure of a drawing machine. It is sectional drawing which shows the structure around the die of the drawing machine at the time of use. It is a front view of the conventional die for drawing process. It is a perspective view of the conventional die for drawing process. It is sectional drawing of the conventional die for drawing process. It is an enlarged view which enlarged the part of the "corner" of the conventional drawing die of the part corresponding to the range x of FIG. It is a front view of the die for drawing process which concerns on this invention. It is a perspective view of the die for drawing process which concerns on this invention. It is sectional drawing of the die for drawing process which concerns on this invention. It is an enlarged view of the part corresponding to the range X of FIG. 7, which is the "corner" part of the drawing die which concerns on this invention. It is a figure showing the bar material having a substantially polygonal cross section manufactured by using the die which concerns on this invention. It is a figure which shows the twist bar which has the substantially polygonal cross section manufactured by using the die which concerns on this invention. It is an enlarged view which shows the cross section of the die of another form which concerns on this invention. It is a front view of the conventional welded wire mesh. It is a front view which shows the 1st wire mesh using the twist bar which concerns on this invention. It is a front view which shows the 2nd wire mesh using the twist bar which concerns on this invention. It is a front view which shows the 3rd wire mesh using the twist bar which concerns on this invention.

An object of the present invention is to prevent the generation of lumps of lubricant as much as possible and to prevent man-hours for maintenance thereof. That is, the number of polygonal cross-section wire rods produced is increased by preventing the powdery lubricant from staying in one place and making it easier for the lumps to fall off when lumps are generated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First Embodiment)

FIG. 3 is a front view of the conventional drawing die 901. Further, FIG. 4 is a perspective view of the drawing die 901. FIG. 5 is a cross-sectional view of the drawing die 901. FIG. 6 is an enlarged view of an enlarged portion of the “corner” portion of the drawing die 901 at the portion corresponding to the range x of FIG.

Further, FIG. 7 is a front view of the drawing die 101 according to the present invention. FIG. 8 is a perspective view of a drawing die 101 according to the present invention. Further, FIG. 9 is a cross-sectional view of the drawing die 101 according to the present invention. FIG. 10 is an enlarged view of an enlarged portion of the “corner” portion of the drawing die 101 according to the present invention, which corresponds to the range X of FIG. 7.

Even with the drawing die 101 according to the present invention, the names of the bearings and other parts do not change. Therefore, the names of each part of the drawing die 101 are described in the 100s, such as the bearing part 101b in the specification.

The basic configuration is the same for the drawing die 101 and the drawing die 901. As can be seen from FIGS. 4 and 8, each die has a substantially cylindrical shape, and a bearing portion that determines the cross-sectional shape of the finished wire rod A-2 after molding on the central axis of the substantially cylindrical shape. The opening is open.

However, the features of the present invention can be understood by looking at FIGS. 6 and 10.

In the conventional drawing die 901, for the purpose of making the corners of the bar members at right angles, the two sides of the cross section of the bearing portion 901b are directly abutted without processing. Therefore, when the cross-sectional shape of the bearing portion 901b is a quadrangular cross section as shown in FIGS. 3 and 6, the sides intersect at right angles.
Here, the cross-sectional shape of the opening of the bearing portion 901b of the die 901 shown in FIG. 6 is a quadrangle which is a kind of polygon. This is called the "basic polygonal cross section".

On the other hand, FIGS. 7 and 10 show the bearing portion 101b of the drawing die 101 according to the present invention. The cross-sectional shape of the bearing portion 101b according to the present invention is characterized in that the portion corresponding to the "corner" of the "basic polygonal cross section" shown in FIG. 6 is replaced with an arc, that is, a curved line. Specifically, when creating a bar having a quadrangular cross section with a side of 4 mm, one "corner" of the opening of the bearing portion 101b of the drawing die 101 is an arc (curve) having a radius of about 0.8 mm. ).
As a result, the lumps of lubricant accumulated in the "corners" are less likely to solidify in one place.

In the drawing die 101 according to the present invention, all four "corners" of the quadrangular cross section, which is the "basic polygonal cross section", are processed in this way. As a result, it becomes difficult for the lubricant to collect at all positions of the die.

In the present specification, a shape in which at least one corner of a "quadrangle" is rounded, that is, a shape in which one "corner" or all "corners" are rounded is also referred to as a "substantially quadrangle". Similarly, a shape obtained by rounding one "corner" to all "corners" of a polygon including a quadrangle is referred to as a "substantially polygon".

Similarly, a triangle with rounded corners is called a "approximately triangle", and a hexagon with rounded corners is called a "approximately hexagon". Hereinafter, even if the polygon has more corners, it will be referred to in the same manner.

This eliminates the "corners" where the lubricant accumulates. As a result, the die 101 behaves in the same manner as a circular cross-section die, making it difficult for a lump of lubricant to form.

In addition, the following measures are taken in the present invention.
The length of the approach portion 101a of the drawing die 101 is shortened as much as possible, and the angle of the half-width β / 2, which is the approach angle (= opening degree), is made as wide as possible. That is,

Fig. 9 (uppercase beta) / 2> Fig. 5 (lowercase beta) / 2 (Equation 1)
L1 <l1 (Equation 2)

Will be. As a result, even if a lump of lubricant is formed, it will easily come off naturally. In the applicant's experiment, when L1 is set to about 1.5 mm and the dice half-width ((lowercase beta / 2 in FIG. 5) or (uppercase beta in FIG. 9) / 2) is 5 degrees or more, a lump of lubricant is formed. Even if it was done, it tended to be easy to drop out.

Further, the same process is applied to the back relief portion 101c as well as the approach portion 101a. That is, the length of the back relief portion 101c is shortened, and the angle (opening) of the back relief is adjusted accordingly.

(Uppercase gamma) / 2 in Fig. 9> (Lowercase gamma) / 2 in Fig. 5 (Equation 3)
L2 <l2 (Equation 4)

Take as wide as possible. This prevents the lubricant from forming lumps on the back relief side as well.

As a result, by taking the correspondence between the approach portion 101a and the back relief portion 101c as described above, the width w of the conventional drawing processing die 901 shown in FIG. 4 and the drawing processing according to the present invention shown in FIG. 8 The width W of the die 101 is

W <w (Equation 5)

This is because This can be realized by comparing FIGS. 4 and 8.

Even if the width of the dice is thinned in this way, it is unlikely to cause a problem in actual operation. The pressure applied to the die is such that the wire rod A undergoes plastic deformation.
When controlling the accuracy of the finished wire A-2, it is necessary to replace it at regular intervals, but in the present invention, it is assumed that the die itself is replaced in 1-2 days, and such a short time. This is because the entire drawing die will not be broken in time.

With these measures, the work pause time for removing the lump of the lubricant can be reduced, and the entire work time can be effectively utilized for manufacturing. As a result, it becomes possible to reduce the manufacturing cost of the steel bar having a polygonal cross section.

FIG. 11 is a perspective view showing a bar material produced by the above-mentioned drawing die 101. As can be seen in this figure, the corners of the bar are rounded.

In addition, by rounding the "corners" of the die, the corners of the steel bar having the completed polygonal cross section are also rounded. As a result, when the user holds the steel rod with his / her bare hands, he / she does not have to cut his / her hand, and has a secondary effect that the safety can be improved.

The above measures are similarly effective when manufacturing a twist bar.

The twist bar can be manufactured by the die holder 902 continuously rotating the die according to the position of the guide rail 904 in which the drawing machine 903 is present. At this time, it can be easily applied by changing the die set in the die holder 902 from the die 901 to the drawing die 101.

As described above, since the opening of the bearing portion 101b of the drawing die 101 has no corner, even if the drawing die 101 is rotated, the lubricant does not accumulate in one place, resulting in a lump of lubricant. Is difficult to do. In addition, by widening the angle of approach and the angle of back relief, even if a lump is formed, it can easily fall off naturally. Of course, these are also effective in the production of twist bars.

On the contrary, when the twist bar is produced, the drawing die 101 always keeps rotating around the central axis of the substantially cylindrical shape. Due to the rotational force on the drawing die 101, the lumps of the lubricant accumulated in the approach portion 101a are reduced from staying in one place, and the lumps of the lubricant are less likely to be formed. Further, the lump of the lubricant once accumulated is likely to fall off from the opening of the approach portion 101a. As a result, when the twist bar is produced, there is an effect that the lump of the lubricant is less likely to accumulate in the approach portion 101a.

Furthermore, from the viewpoint of the finished product, there is an advantage over the bar material in manufacturing the twist bar. FIG. 12 is a perspective view of a twist bar created by using the drawing die 101 according to the present invention.

When using rods, they are often used for concrete reinforcing bars. In this case, since there are "corners" in the bar material, concrete is caught and the pull-out strength is maintained.

Therefore, rounding the corners may be disadvantageous in terms of pull-out strength. However, when the reinforcing bar is knitted using the twist bar, the pull-out strength is increased by the “twist” of the twist bar itself, so that even if the corners are rounded, there is no problem in terms of strength. In addition, "twisting" is defined as applying force to both ends of a "slender object" and turning them in opposite directions (Shogakukan "Daijisen"). Therefore, please be careful not to make an interpretation contrary to this meaning.

Further, even in the twist bar manufactured by the manufacturing method of the present application, by rounding the "corners" of the die, the corners of the completed twist bar are also rounded. As a result, as with the steel bar having a polygonal cross section, the user does not have to cut his / her hand when holding the twist bar with his / her bare hands, and the safety can be improved.

It goes without saying that the invention relating to the present embodiment is not limited to the above-described embodiment, and various changes can be made without departing from the gist thereof.

In the above, an arc was used to erase the "angle", but it may be configured as a set of obtuse angles.
FIG. 13 is a diagram showing a set of obtuse angles. That is, it is also included in the range of the present invention that a "corner" composed of one 90-degree angle is composed of nine obtuse angles so as not to accumulate in one place. Moreover, there is no problem even if the "corner" is replaced with a free curve, not limited to an arc.

Also, depending on the situation, even one with only one or two rounded corners may withstand use. This is because when making a bar, if only the corner that comes to the bottom of the die is rounded, the lubricant may not collect.

Further, a drawing machine using the drawing die 101 according to the present invention is naturally included in the range of the present invention.

Further, when making a twist bar using the drawing die 101 according to the present invention, 1) rotating the drawing die 101 according to the position of the drawing machine 903 on the guide rail 904 (explained). 2) The die holder rotates the drawing die 101 according to the present invention according to the elapsed time from the work start time, and 3) the drawing die 101 according to the distance traveled by the drawing machine after the start of machining. Of course, the rotation of the present invention is also included in the range of the present invention.

Furthermore, it has been described whether the drawing machine 900 that moves linearly is used in the embodiment. This is because the linearity of the finished wire A-2 is taken into consideration. However, if the linearity of the finished wire A-2 is not a concern, the drawing machine 900 is replaced with a drawing device that winds the finished wire A-2 around a drum driven by an electric motor. A processing machine may be used. When making a twist bar using a drum, the die holder 102 rotates the drawing die 101 according to 4) the number of rotations of the drum, 5) the elapsed time from the start of work, and 6) the angular velocity of the drum. Will let you.

(Second Embodiment)
Hereinafter, the second embodiment will be described.

As described above, it has been described that the twist bar can be manufactured at low cost by using the first embodiment of the present invention (see FIG. 12).
In the second embodiment of the present application, the manufacture of wire mesh using this inexpensive twist bar will be described.

"Welded wire mesh" refers to a wire mesh in which iron wires are arranged orthogonally and their intersections are electrically resistance welded to form a grid. Conventionally, the welded wire mesh shown in JIS G 3551 (non-patent document) and the like has been created by combining "round iron wires" in a grid shape.

FIG. 14 is a front view of a conventional welded wire mesh.
The welded wire mesh shown in FIG. 14 is manufactured by using round iron wire and combining them in a grid shape. Here, the "round iron wire" refers to an iron wire having a circular cross-sectional shape (defined in JIS G 3551).

In JIS G 3551, among the reinforcing bars that make up the reinforcing bar grid in the wire net, the "vertical line" is the iron wire or bar wire in the manufacturing direction (machine feed direction), and the horizontal line is perpendicular to the manufacturing direction (machine feed direction). Defined as a directional iron wire or bar wire. However, it should be noted that in the present specification, among the iron wires constituting the wire mesh, those arranged in any one direction are defined as "vertical lines", and the iron wires in the direction orthogonal to the vertical lines are defined as "horizontal lines".

The vertical lines 501a, 501b, 501c, 501d and the horizontal lines 502a, 502b, 502c, 502d made of the "round iron wire" represented by FIG. 14 are shown in FIG. 12 of the first embodiment of the present invention. The second embodiment of the present application is to replace it with a twist bar having a polygonal cross section.

FIG. 15 is a front view showing a first wire mesh using a twist bar according to the present invention. As is clear from this figure, all the vertical and horizontal lines shown in FIG. 14 are replaced with vertical lines 601a, 601b, 601c, 601d and horizontal lines 602a, 602b, 602c, 602d, and joined by a pneumatic multi-spot welder or the like. To do.

As described above, when the reinforcing bar is knitted using the twist bar, the pull-out strength is increased by the twisting itself of the twist bar. Further, according to the first embodiment, the yield at the time of manufacturing the twist bar is improved, and as a result, the cost price of the wire mesh using the twist bar is also reduced.

By doing so, it is possible to reduce the weight per unit length while maintaining the same strength as the conventional round iron wire. As a result, the weight of the entire welded wire mesh can be reduced.

Further, FIG. 16 is a front view showing a second wire mesh using the twist bar according to the present invention. In this figure, it is the figure which shows the welded wire mesh when the horizontal lines 502a, 502b, 502c, 502d of FIG. In this figure, the vertical lines 701a, 701b, 701c, and 701d are round iron wires. Of course, there is no problem applying the twist bar only to the vertical lines.
By doing so, it is possible to provide wire mesh having different characteristics in the vertical line direction and the horizontal line direction.

Further, FIG. 17 is a front view showing a third wire mesh using the twist bar according to the present invention. FIG. 17 is a diagram showing a welded wire mesh when the ratio of the round iron wire and the polygonal cross-section metal wire is 1: 1 for both the vertical line and the horizontal line. That is, the vertical lines 501b and 501d and the horizontal lines 502b and 502d in FIG. 14 are replaced with the twist bars according to the present invention.

That is, the twist bar according to the present invention is used for the vertical lines 801b and 801d and the horizontal lines 802b and 802d. On the other hand, round iron wires are used for the vertical lines 801a and 801c and the horizontal lines 802a and 802c. By doing so, it is possible to provide a wire mesh that can be used without being aware of the vertical line direction and the horizontal line direction.

Further, in FIG. 17, the ratio of the round cross-section metal wire to the twist bar was 1: 1. However, the ratio may be changed to 1: 2 or 2: 1 (of course, other ratios are possible) as appropriate. Further, the ratio of the round cross-section metal wire and the twist bar may be changed between the vertical line and the horizontal line. By using wire rods with different characteristics in this way, it is possible to make a lightweight wire mesh while having a certain degree of resistance to "drawing".

Further, the characteristics of the entire wire mesh can be easily adjusted by the ratio of the round iron wire and the twist bar according to the present invention. As a result, it becomes possible to give variety to the wire mesh and develop various products.

Further, although only the round iron wire and the twist bar related to the present invention have been described above, the polygonal cross-sectional wire rod (not twisted) related to the present invention, the polygonal cross-sectional wire rod not related to the present invention, and the present invention Not a twist bar, one using a deformed iron wire defined by JIS G 3551 also naturally falls within the range of the present invention. Further, one wire mesh may be manufactured by three or more kinds instead of two kinds.

As described above, the mixing of the round cross-section metal wire and the twist bar in one wire mesh is also included in the range of the present invention. On the contrary, it is also possible to adjust the properties by mixing as shown in FIG. 17 and increase the development of product variations without using the polygonal cross-section wire rod or the twist bar included in the first embodiment of the present invention. It can be said that it is included in.

When used as the foundation of a building, even if the configuration is as shown in FIGS. 16 and 17, by using the twist bar according to the present invention, the adhesiveness with concrete can be ensured.

As described above, the welded wire mesh using the twist bar according to the present invention makes it possible to produce a low-priced and lightweight welded wire mesh having high adhesion to concrete without using an expensive "deformed iron wire".

Although the invention made by the present inventor has been specifically described above based on the embodiment, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof. Needless to say, there is.

The present invention is used for improving the die used in the drawing process and reducing the cost of the finished wire rod A-2 manufactured by using the die.

A: Wire rod,
A-1: Material wire rod,
A-2: Completed wire rod,
101a, 901a: Approach section,
101b, 901b: Bearing part,
101c, 901c: Back relief part,
101d, 901d: the fitting hole,
501a, 501b, 501c, 501d: vertical lines,
502a, 502b, 502c, 502d: horizontal line,
601a, 601b, 601c, 601d: vertical line,
602a, 602b, 602c, 602d: horizontal line,
701a, 701b, 701c, 701d: vertical lines,
702a, 702b, 702c, 702d: horizontal line,
801a, 801b, 801c, 801d: vertical line,
802a, 802b, 802c, 802d: horizontal line,
900: Extraction machine,
101, 901: Die for drawing process,
902: Die holder,
903: Drawing machine,
904: Guide rail,
905: Box.

Claims (1)

A drawing for forming a twist bar having a substantially polygonal cross section, wherein at least one corner of the substantially polygonal shape of the twist bar is rounded from the beginning to the end in the drawing direction. It is a die for processing
The die is provided with a fitting portion for fixing to the die holder so as to rotate in the circumferential direction together with the die holder during the drawing process of the material wire.
The opening of the bearing portion of the die has a substantially polygonal cross-sectional shape, and the substantially polygonal shape is obtained by replacing at least one corner of the underlying polygon with an arc or a curved line. A die for drawing, in which the cross-sectional shape of the opening is the same along the drawing direction of the material wire.

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