JPH03210924A - Manufacture of rib lath - Google Patents

Abstract

PURPOSE:To prevent strain and internal stress from generation and to easily obtain a high-performance rib lath by deviating a group of vertical rib parts on one side arranged every other rib vertically to one side to a group of vertical rib parts on the other side, developing the section vertically and zigzagly, then, correcting the section in the flat shape. CONSTITUTION:A group of vertical rib parts 14a on one side arranged on every other rib by upper and lower development guides 11 is deviated to vertically to the same direction to vertical rib parts 14b on the other side. As the advancing speeds of the group of both vertical rib parts 14a, 14b projected on the surface are kept equal, in the development of the network 8, detour of an amount equivalent to the delay can be made by a locus deviated in one vertical direction for the group of vertical rib parts 14a where the advancing speed is delayed relatively. In this case, since the upper and lower development guides 11 are provided separately in each vertical rib part 14, the amount of detour can correspond strictly to the delay of speed - of each vertical rib part 14a and generation of distorsion can be prevented, the frictional resistance between the guide 11 and each vertical rib part is reduced and residual stress is hardly developed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing metal lath, particularly rib lath having longitudinal ribs at appropriate intervals, used as weir plates of formwork in the construction of concrete structures.

Conventional technology In general, this type of libras is produced by forming a plurality of slit rows consisting of convex-shaped slits cut at regular intervals along the longitudinal direction on a strip-shaped thin metal plate using a press die or roll die, and then running the thin plate. It is manufactured by a method in which one non-slit region is bent into a groove shape to form a plurality of vertical ribs, and the thin plate is stretched in the width direction to develop a mesh.

Conventionally, the mesh development process involves a belt-shaped thin metal plate (
1) is passed through the width determining device (2), and each non-slit area (1b) is formed into a longitudinal rib (4) by using a grooved roll (3). The thin plate (1
) is most commonly used to stretch the material in the width direction by simply passing it through.

In addition to the above method, in order to improve deployment efficiency and shorten the line length, as shown in FIG.
A step-wise development roll (6) in which the small-diameter roll portions (6b) and small-diameter roll portions (6b) are alternately fixed to one shaft is used, and the thin plate (1) is attached to this roll.
A roll part (6) is attached to each vertical rib (4) formed in the same manner as above.
a) By passing with (6b) fitted,
- Deploy it in a zigzag pattern, then horizontally deploy the guide (5
) has also been proposed.

Problems to be Solved by the Invention However, with the developing method as shown in FIG. There was also a problem of low yield and productivity. On the other hand, the development method shown in FIG. 9 alleviates the above-mentioned problems to some extent, but it is not enough, and the ribs obtained are limited to those in which the vertical ribs (4) have a sharp V-shaped cross-section. There was a problem.

According to the studies of the present inventors, the cause of such problems is considered to be as follows.

First, the mechanism of mesh development will be explained by taking as an example the case where a convex-shaped slit (7) formed in a thin plate (1) is divided into two on both sides as shown in Fig. 6(a). In order to develop and form a parallelogram lattice mesh (8) as shown in FIG. 6(b) by stretching the thin plate (1) in the width direction, a part of the strip between the slits (7) (7) is formed. Each horizontal piece (8a) consisting of a vertical rib (4a) or (4b
), and for this purpose, for example, the center point (P
1) and the outer point (P2) are separated as shown in FIG. 6(b). Therefore, in the unfolding process, which is carried out while the thin plate (1) is traveling in the direction of the arrow in the figure, for example, the adjacent vertical ribs (4
There is inevitably a difference in the advancing speed between a) (4b), and the relative advancing speed of the vertical ribs (4a) arranged every other group is forced to be relative to the vertical rib (4b) group located between them. will be delayed.

However, in the development method shown in FIG. 7, the vertical ribs (4
The group a) cannot make a detour and is forced to travel parallel and straight the same distance as the other group of vertical ribs (4b), resulting in large distortions in the entire rib, and as shown in Figure 8, the above distortion becomes severe. Dart phenomenon (
9a) or twisting (9b) of the vertical rib (4a) itself, deteriorating the flatness of the rib (lO), and in severe cases, the distortion cannot be fully absorbed and the vertical rib (8) of the mesh (8) deteriorates.
A break (9c) occurs in the part along 4a), and furthermore, the obtained replus will easily break or change dimensions when external force such as impact is applied during handling or use due to residual stress. . Furthermore, even during deployment, a very large frictional resistance is generated between the vertical rib (4a) and the guide (5) as a reaction force to the above distortion, so that the vertical rib (4a) comes off from the guide (5). There were quite a few accidents, which caused a decline in yield and productivity.

On the other hand, in the development as shown in FIG. 9, the circumferential speed of each roll portion (6a) (6b) of the stepped development roll (6) that rotates integrally with each vertical rib (4) of the thin plate (1) to be developed in a zigzag pattern.
Since the traveling speed does not match the advancing speed, the strain is not completely eliminated, and in addition, a large frictional resistance is generated between the roll portion (6a) and the vertical rib (4a), so it is difficult to remove the residual stress. could not. In addition, due to the above-mentioned frictional resistance, it is necessary to increase the accuracy and strength of the clearance of the deployment guide (5), and the vertical rib (4) is
), and the contact area is small, the cross-sectional shape must be a sharp V-shape, etc., and those having vertical ribs with a U-shaped cross-section, which are particularly useful, cannot be targeted. There wasn't.

In view of the above-mentioned circumstances, this invention prevents the occurrence of distortion in the unfolding process with a simple device, has excellent flatness and high commercial value in terms of appearance, and also prevents breakage during handling or use due to residual stress. It is an object of the present invention to provide a method for easily and stably producing ribrus that is less susceptible to dimensional changes and has no restrictions on the cross-sectional shape of the longitudinal ribs.

Means for Solving the Problems, that is, the manufacturing method of Ribrass according to the present invention, in order to achieve the above object, eight-figure slits (7) are cut at regular intervals along the longitudinal direction of the strip-shaped thin metal plate (1). After forming a plurality of slit rows (1a), the thin plate (1) is run and its non-slit area (1b) is curved into a groove shape to form a plurality of vertical ribs (4). , the thin plate (
1) in the width direction to develop and form the mesh (8).
One vertical rib part (
14a) group to the other vertical rib portion (
14b) Vertical development guides (11) and (12) that are shifted upward and downward to one side with respect to the group are individually provided in each vertical rib part (14), and by passing the thin plate (1) through these guides, a vertical zigzag shape is formed. The structure is characterized in that the material is expanded in the width direction and then flattened.

Function: The vertical expansion guides (11) and (12) shift one group of vertical ribs (14a), which are arranged every other time, to one side above and below with respect to the other vertical ribs (14b).
While the advancing speed projected onto the plane of both vertical rib sections (14a) and (14b) group is the same, the longitudinal rib section (14a) whose advancing speed should be relatively delayed in the development of the mesh (8)
) group can be detoured by a trajectory that is shifted upward or downward in one direction by an amount corresponding to the amount of delay. Moreover, in this case, since the vertical deployment guides (11) and (12) are individually provided for each vertical rib portion (14), the amount of detour described above is adjusted to the amount of speed delay of each vertical rib portion (14a). This makes it possible to ensure exact correspondence, thereby completely preventing the occurrence of distortion, and the frictional resistance between the guides (11, 12) and each vertical rib (14) is extremely small, minimizing residual stress. Does not occur.

Therefore, at the stage of the vertical zigzag development, the development in the width direction that should be finally stretched is completed, and in the next step, it is only necessary to straighten the zigzag shape to a flat shape. Almost no stress is generated.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

Fig. 1 shows the first embodiment of the unfolding process in the method of the present invention, in which the width determining device (2), the grooved and dual-purpose feed A roll (13), a vertical deployment guide (11), and a horizontal deployment guide (15) are provided. However, thin plate (1)
A plurality of slit rows (1a) consisting of 8-shaped slits (7) (Fig. 3) are formed at regular intervals along the longitudinal direction using a press mold or a roll mold according to a conventional method. These slit rows (la) (l
The longitudinally continuous band-shaped non-slit regions (1b) existing between the gaps a) and on both sides of the thin plate (1) become the longitudinal rib portions (14) forming the above-mentioned longitudinal ribs (4).

The grooved dual-purpose feed roll (13) mentioned above is the feed roll (
13a) and grooved rolls (13b) are attached alternately to two rotating shafts, and by passing the thin plate (1) positioned by the width determining device (2), the multiple rows of rolls (13b) are attached alternately to the rotating shaft. Grooving of every other row of the non-slit area (1b), that is, a group of vertical rib portions (14b), is performed using a roll (13
b) is formed into a vertical rib (14) shape with a U-shaped cross section, and a feed roll (13a) rolls into contact with the rows of non-slit areas (1b) between them, that is, the group of vertical ribs (14a) to form a flat surface. I'll send it out in a state.

As shown in FIG. 2, the vertical deployment guide (11) alternately moves a pair of independent push-down rolls (11a) and a horizontal feed roll (llb), and the latter (llb).
is at the same level as the thin plate (1) into which the former (lla
) are arranged at different levels so that they are a predetermined distance lower than the level.

Thus, each push-down roll (lla) applies each horizontal feed roll (llb) to each longitudinal rib (14a) of the thin plate (1).
) are similarly set at positions corresponding to each of the vertical rib portions (14b), and the former (lla) has a flat circumferential shape in order to sandwich the flat vertical rib portion (14a), The latter (llb) is a vertical rib part (14) with a U-shaped cross section.
b') has a circumferential surface with vertical unevenness.

In this vertical development guide (11), the thin plate (1) fed out from the grooved and dual-purpose feed roll (13) has vertical rib portions (14b) set to the horizontal feed roll (llb) group so that the thin plate (1) is at the feeding level. While it is held in place, press the vertical rib part (
Since the groups 14a) are each pushed down and guided downward by the push-down rolls (lla), the distance between the adjacent vertical ribs (14a) and (14b) expands diagonally up and down, as shown in FIG. Each slit row (
As a result of expanding the slits (7) of 1a) and developing the mesh (8), a vertically zigzag-like expanded form is formed with the vertical rib portions (14b) as the peaks and the vertical rib portions (14a) as the valleys. Note that the amount of development of the mesh (8) is set to correspond to the amount of development in the finally obtained librus (10).

Here, the vertical rib portion (14a) is forcibly delayed in its advancing speed relative to the vertical rib portion (14b) during the above development process, but the length corresponds to the amount of this speed delay. Since the displacement is set to match the increase in moving distance due to the downward detour by the push-down roll (lla), the planar projection speed is the same as that of the vertical rib portion (14b). Therefore, in the above development process, both vertical rib portions (14a) (14
b) No distortion occurs due to the speed difference, and each roll (
Since the frictional resistance in 11a) (llb) is very small and the developed state of the mesh (8) is the same V as the final developed state in the replus (10), almost no residual stress is generated.

Each horizontal deployment guide (15) is composed of a pair of upper and lower strip pieces, and the number of strips corresponding to the number of vertical ribs (14b) (four in the figure) are the upper and lower deployment guides (11).
) are arranged so as to spread radially in a horizontal plane toward the feed downstream side from immediately after each horizontal roll (llb), and are fitted from above and below into vertical rib portions (14b) each having a U-shaped cross section to form the vertical ribs. The direction of movement of the portion (14b) is regulated. However, the vertical expansion guide (15)
The thin plate (1) sent out in a vertical zigzag pattern is gradually flattened in the process of passing through this horizontal expansion guide (15) and becomes a planar replus (10), but in this process it is substantially stretched. Since the zigzag shape is simply corrected into a flat shape without being subjected to any action, almost no distortion or residual stress is generated.

The flat vertical rib portion (14a) is fed out from the horizontal expansion guide (15) and then formed into a U-shaped cross section by a grooved roll (not shown) to form the vertical rib (4). It turns out.

FIG. 4 shows a second embodiment of the unfolding step in the method of the present invention, which is similar to the first embodiment except that the roll-type vertical unfolding guide (11) is replaced with the fixed-type upper-lower unfolding guide (12) shown in the figure. It has the same configuration as the embodiment.

That is, the vertical expansion guide (12) of this second embodiment has downwardly curved push-down guiding slits (16) at positions corresponding to the respective vertical ribs (14a) of the thin plate (1).
A guide plate (12a) is arranged, and a horizontal deployment guide (12a) is arranged at a position corresponding to each vertical rib part (14b).
A guide portion (12b) constituted by the extension portion of 5) is arranged.

As in the case of the first embodiment, the thin plate (1) fed out from the grooved and dual-purpose feed roll (13) passes through this vertical development guide (12), thereby allowing the vertical rib portion (14b ) group is held at the feeding level by the guide part (12b) group, and the vertical rib part (14a) group is pushed down and guided downward by the guide slit (IB) of the guide plate (12a) group. , the mesh (8
) is expanded and formed into an upper and lower zigzag shape,
Thereafter, it is corrected to be flat by a horizontal expansion guide (15).

Of course, in this case as well, the length displacement corresponding to the delay in the advancing speed due to the expansion of the vertical rib portion (14a) is caused by the length displacement of the guide plate (12a).
) is set to match the increase in travel distance due to the induction slit (16), and therefore almost no distortion or residual stress occurs.

Note that the form and structure of the vertical expansion guide employed in the method of this invention are not limited to those of the first and second embodiments described above, and can be modified in various ways. You may also do so. In addition, in the two embodiments described above, the vertical rib (
14a) By introducing the group into the unfolding process in a flat state, the resistance to vertical displacement by the upper and lower unfolding guides is minimized. It is also possible to form it in advance into a vertical rib shape such as a U-shape in cross section and then lead it to the unfolding process. Furthermore, in this invention, detailed configurations such as a horizontal expansion guide for flattening a zigzag shape, a means for forming a vertical rib shape, the number of divisions of convex slits formed in a thin plate, and the width and number of slit rows are as follows. Various settings can be changed other than those shown in the example.

Effects of the Invention According to the method of the present invention, the strip-shaped metal strips each having a row of slits are arranged in every other strip by passing through the upper and lower expansion guides provided individually corresponding to each vertical rib portion of the strips. After shifting one group of vertical ribs to one side up and down with respect to the other group of vertical ribs and developing it in a vertical zigzag shape in cross section,
Since it is straightened into a flat shape, it is possible to completely prevent the occurrence of distortion and internal stress during the unfolding process.It has excellent flatness and has high commercial value in terms of appearance, and it also prevents breakage and dimensional changes during handling and use. In addition to being able to easily and inexpensively provide extremely high-performance repluses that are unlikely to occur, there is no risk of the vertical ribs coming off from the deployment guide, etc. during deployment, and the yield and productivity of replus production can be dramatically increased compared to conventional methods. It is possible. In addition, the method of the present invention has the advantage that there is no restriction on the cross-sectional shape of the longitudinal ribs of the ribs to be obtained, and even ribs having a U-shaped cross section, which is highly useful, can be stably manufactured at a low location.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a first embodiment of the unfolding step in the method of the present invention, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG.
FIG. 3 is a perspective view of the main parts showing the unfolding operation of the thin metal plate in the same embodiment, FIG. 4 is a perspective view showing the second embodiment, and FIG.
The figure is a cross-sectional view taken along line V-v in FIG. 4, FIG. 6(a) is a plan view showing an example of a thin metal plate before development, and FIG. 6(b) is a plan view of Replus after development. Fig. 7 is a perspective view showing an example of a developing process in a conventional method, Fig. 8 is a perspective view of a main part showing a defective state of librus obtained by the conventional method, and Fig. 9 is a perspective view showing an example of a developing process in another conventional method. It is a perspective view showing an example. (1)...Metal thin plate, (1a)...Slit row, (
1b)...Non-slit area, (4)...Vertical rib, (
7)...Slit, (8)...Mesh, (10)
... rib brass, (11) (12) ... vertical development guide, (14) (14a) (14b) - vertical rib portion.

Claims (1)

[Claims] After forming a plurality of slit rows consisting of V-shaped slits cut at regular intervals along the longitudinal direction on a strip-shaped thin metal plate, the thin plate is run and the non-slit area is bent into a groove shape to form a plurality of vertical slits. In the replus manufacturing method, in which ribs are formed and the thin plate is stretched in the width direction to develop and form a mesh, one group of longitudinal ribs arranged every other time is placed at the end of the opening of the mesh between them. Each vertical rib section is individually provided with a vertical expansion guide that is moved upward or downward to one side with respect to the other vertical rib group, and the thin plate is passed through these guides to expand it in an up and down zigzag pattern. A method for manufacturing replus, which is characterized by expanding in the direction and flattening it.