JPH02192822A - Method and apparatus for cold roll forming - Google Patents

Abstract

PURPOSE:To automatically and suitably adjust the clearance between rolls according to the plate thickness of a steel plate by receiving the forming load of a rolling roll or a working roll with plural belleville springs having a specific spring characteristics when a steel stock is cold-rolled, worked by plural forming units to manufacture a channel steel material, etc. CONSTITUTION:Material 2 to be formed such as steel plate is passed through a guide stand 3 and six stages of horizontal roll stands 4 (P1 - P6) for the special purpose of driving and light weight channel steel, etc., are rolled and worked by non-driven forming units 5 (R1 - R10) equipped in the middle. When the steel plate stock 2 is worked by the forming unit 5 into the channel steel, the load for a web 2a, forming roll 12, a flange 2d, forming roll 13 and an abutting roll 14 for forming a lip part is received by plural belleville springs made of material having specific spring characteristics, each clearance between rolls is adjusted automatically according to the thickness of the steel plate 2 passing through each roll and the plate thickness of a product thin section can be adjusted freely.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cold roll forming method and apparatus, and particularly to a plate thickness adjusting means for adjusting roll clearance in accordance with the plate thickness of a forming material, and The present invention relates to a plate thickness adjusting means suitable for application to a so-called roller die forming apparatus.

[Prior Art] In cold roll forming equipment, when the thickness of the material to be formed changes, it is necessary to adjust the clearance between the upper and lower rolls according to the thickness. The upper roll is rigidly supported so that it can be moved up and down, such as by supporting the upper roll via a reduction screw or by interposing a removable thickness adjustment liner in the support part of the upper roll. It is a structure.

By the way, as a roll forming method suitable for forming lightweight channel steel, etc., the feeding drive of the material is performed using a dedicated roll stand (that is, a feeding unit) that has upper and lower cylindrical drive rolls, and the forming of the material is , a forming unit that functions as a roller die placed between each feeding unit, that is, a set of three reversing rollers that contact the vicinity of the bending corner of the forming material, each of which is movable and adjustable in the width direction of the material. A method of performing this in units has been known for some time.

As an improvement to the molding equipment using this roller die molding method,
The present applicant has provided a forming device having a structure in which an abutment roller that contacts the inside of the corner portion of three idle rollers is rotatably supported in the thickness direction of the corner rounded portion around a fulcrum pin perpendicular to the material advancing direction. In this forming apparatus, the abutment roller is rigidly supported.

[Problems to be Solved by the Invention] The roller die molding method described above has various advantages, as well as the advantage that it is easy to rearrange the product when changing the external size of the product. The above-mentioned optical patent application further increased the advantages of the roller die forming method by making it easier to adjust the roll clearance, that is, adjust the plate thickness, especially when changing the product plate thickness. The support is a rigid support structure, and it is necessary to adjust the plate thickness in response to changes in plate thickness. It would be even more desirable if such plate thickness adjustment work became unnecessary.

The present invention has been made in view of the above circumstances, and includes a cold roll forming method and a cold roll forming method in which thickness adjustment is automatically performed according to the thickness of the formed material to be passed, eliminating the need for sheet thickness adjustment work. The purpose is to obtain equipment.

[Means for Solving the Problem] The invention of claim 1 which solves the above problem is such that the displacement-repulsion force curve representing the relationship between the spring displacement and the spring repulsion force expresses the relationship between the plate thickness of the forming material and the forming load. This cold roll forming method is characterized in that the forming load is applied by a spring having spring characteristics similar to the expressed plate thickness-forming load curve.

According to a second aspect of the invention, the spring is constructed by combining a plurality of disc springs.

A third aspect of the invention is a cold roll forming apparatus that implements the above forming method.

The invention according to claim 4 is applied to a cold roll forming apparatus employing a so-called roller die forming method.

The invention according to claim 5 provides a roller die having a configuration in which a roller holder that supports the abutment roller is rotatably attached to a movable support plate in the thickness direction of the corner rounded portion about a fulcrum pin perpendicular to the direction of movement of the material. In the molding equipment,
The spring is interposed between the roller holder and the movable support plate.

[Function] In the above configuration, each roll is set so that the roll clearance is, for example, zero in a state where the molded material is not passed through. When the formed material is passed through the sheet in this state, the displacement-repulsion force curve of the spring that is present at the part where the forming load is applied is similar to the sheet thickness-forming load curve, so it is rolled by approximately the thickness of the sheet due to the passing. The repulsive force of the spring when a clearance occurs has a magnitude close to the forming load. Therefore, an appropriate roll clearance can be obtained simply by passing the molded material through the plate.

In other words, the plate thickness is automatically determined! 1u11 is performed.

According to the method of configuring the above-mentioned spring by combining a plurality of disc springs, it is easy to obtain a spring having a desired displacement-repulsion force curve corresponding to different molding loads for each molding unit.

In addition, in the case of a roller die forming apparatus having a structure in which a roller holder supporting the abutting roller is rotatably attached to the movable support plate side in the thickness direction of the corner round part around a fulcrum pin, changes in the plate thickness may occur. The present invention is easy to apply and is extremely effective as an automatic plate thickness adjustment means because only one adjustment point is required (namely, only the rotational movement around the fulcrum pin of the roller holder). be.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 11.

FIG. 1 is an overall side view of a cold roll forming apparatus according to an embodiment of the present invention, and 1 is a forming machine base. On the molding machine base 1, a material to be molded 2 (hereinafter simply referred to as the material, the same reference numeral 2 is used for both the stage of a flat plate before molding and the stage of advanced molding).
A guide stand 3 that defines the widthwise position of the roller (indicated by ), and horizontal roll stands 4 dedicated to driving, for example, six stages, designated P+ to P, are installed, and between each roll stand 4 dedicated to driving, R3-R3° A non-driven molding unit 5 shown by is provided. In addition, on the exit side of the drive-only roll stand P6 in the final stage, there is an overvent unit 6 indicated by R1+ for preventing springback, and an RI
A bending-back unit 7 indicated at 2 is provided. In addition,
In this embodiment, as shown in the drawing, a lip channel steel having a web portion 2a, a flange portion 2d, and a lip portion 2C is formed.

As shown in the front view in FIG. 2, the guide stand 3 guides both side edges of the material 2 by means of left and right guide rolls 3a. The drive-only roll stand 4 is shown in FIG. 3, which shows two stages P, , P (i.e., before the start of bending the flange part), and FIG. As shown, material 2
The flat portion of the mold is sandwiched between horizontal upper and lower feed drive rolls 4a and 4b to perform feeding drive, and as shown in the figure, it is only a feeding drive and does not participate in forming.

The molding unit 5 will be described in detail.
As shown in FIG. 5 for No. 3-R7, a first face plate 8 is provided which serves as a common base for two adjacent molding units 5. This first face plate 8 is provided perpendicularly to the upper and lower frames 9 fixed to the drive-only roll stand 4 in front and rear thereof,
The surface is perpendicular to the direction of progress of the molded material (direction of arrow (A) in FIG. 1). Further, the first face plate 8 is provided with a material passage hole through which the material passes. Each first face plate 8 is provided with a pair of left and right second face plates (movable support plates) 11 that are guided by guides 10 and movable in the width direction of the material (for example, in the left-right direction in FIG. 5). . This second
The face plate 11 has material passage holes 11 for passing the material through.
A is open. Further, although not shown, a drive mechanism for moving the second face plate 11 left and right is provided. Further, as shown in FIG. 1, the second face plates 11 are provided on both sides of each first face plate 8. That is, the molding units 5 are provided on both sides of each first face plate 8, respectively.

The second face plate 11 includes an idling cylindrical receiving roller 12 that contacts the bottom surface of the bottom portion (lip channel steel web portion) 2a of the formed material 2 near the corner portion 2b, and a side portion (lip groove). An idling cylindrical side forming roller 13 that contacts the outer surface of the flange portion 2d of the shaped steel, and an idling acute-angled abutting roller 14 that contacts the inner radius of the corner portion 2b are respectively rollers. They are stored as a set via holders 15, 16, and 17. The shaft 18 of the receiving roller 12 is parallel to the bottom side 2a. The axis 19 of the side forming roller 13 is parallel to the side portion 2d.

The axis 20 of the abutment roller 14 is perpendicular to the direction of the bisector of the angle θ of the corner portion 2b. Therefore, the abutting roller 14 rotates within a plane that includes the bisector of the angle θ of the corner portion 2b, as shown in an enlarged view in FIG. 6(A). The radius of curvature of the acute-angled outer peripheral tip edge of the abutting roller 14 is preferably about 1t radius to 3t radius with respect to the plate thickness t.

The roller holder 17, which rotatably supports the abutment roller 14, has an abbreviated shape when viewed from the side as shown in FIG. The lower end of the roller holder receiver 22 is rotatably connected via a fulcrum pin 23 parallel to the shaft 20 of the abutment roller 14, and the other upper end is connected to the bracket 22a of the roller holder receiver 22 as a support mechanism. 24.

To explain the details of the support mechanism 24, the roller holder 1
The flange 25a side of the guide shaft 25 with a flange, which is slidably fitted into the hole 22b made in the bracket 22a, is inserted into the recess 17a made in 7, and the guide shaft 25
A plurality of disc springs 26 and washers 27 are fitted in the holder. As will be described later, this disc spring 26 has a displacement of -
They are combined so that the repulsion force curve (straight line) approximates the plate thickness-forming load curve. A load cell 28 for measuring forming load is installed on the lower surface side of the collar 25a of the guide shaft 25. Two pull-out stops are attached to the upper part of the guide shaft 25.

Next, the operation will be explained.

In FIG. 1, a material 2 is continuously fed out from a material supply device (not shown), its position in the width direction is regulated by a guide stand 3, and fed into a drive-only roll stand 4, followed by a forming unit 5, a drive-only roll. It passes through the stand 4 one after another, and predetermined molding is performed. As shown in FIG. 3 or 4, the drive-only roll stand 4 is a feed drive system in which the flat portion of the material is sandwiched between upper and lower flat feed drive rolls 4a and 4b to simply feed the material. Due to the feed drive of the dedicated roll stand 4, the material is transferred to R1-R.
The material passes through each forming unit 5 of 5°, and the left and right sets of three rollers, the receiving roller 12, the side forming roller 13, and the abutment roller 14 function as roller dies, and the material is sequentially bent and formed. go. In this molding,
Since the abutting roller 14 contacts the corner radius portion in a narrow area, bending by the three rollers 12, 13, and 14 is performed with a small forming force, and sharp bending is possible.

In the above forming apparatus, changing the external size of a product with a similar cross-sectional shape, for example, changing the web part using the same lip shaped steel,
When changing to a product with different dimensions for the flange portion and lip portion, adjust the second face plate 11 by moving it left and right in the forming unit 5 of each stage, and adjust the size of the receiving roller 12, side forming roller 13, and abutting roller. Set of 14 on the left and right
It is moved and adjusted together with the face plate 11 to bring it to the bending position in the forming stage. In this way, by simply adjusting the movement of the second face plate 11, it is possible to mold a wide variety of products with similar cross-sectional shapes and different external sizes.

Then, plate thickness adjustment for adjusting roll clearance in accordance with the plate thickness of the molded material is automatically performed.

That is, each roller is set so that the roll clearance is, for example, zero in a state where the forming material is not passed through. When the forming material is passed through the plate in this state, the abutting roller 14 that receives the forming load rotates upward around the fulcrum pin 23 until the forming load and the reaction force of the disc spring 26 are balanced, and responds to the forming load. Create a gap, or roll clearance. In this case, the displacement-repulsion force curve of the disc spring 26 is equal to the plate thickness-
Since it is similar to the forming load curve, the repulsive force of the disc spring 26 when a roll clearance is generated by the thickness of the plate due to the threading is close to the forming load.

Therefore, an appropriate roll clearance can be obtained simply by passing the molded material through the plate. In other words, the plate thickness is automatically adjusted.

In addition, in the above-mentioned plate thickness adjustment, since the moving direction of the abutment roller 14 is the direction of the bisector of the angle θ of the corner portion, the plate thickness changes in the vertical direction (plate thickness change at the web portion 2a).
It is possible to not only deal with this, but also appropriately deal with changes in plate thickness in the left-right direction (changes in plate thickness at the flange portion 2d). Therefore, the present invention is extremely suitable when applied to a roller die forming apparatus in which the roller holder 17 is rotatable about the fulcrum pin 23 in the direction of the bisector of the angle θ of the corner radius portion, as in this embodiment. It is. In other words, with a normal forming machine that performs forming using upper and lower horizontal rolls, the roll clearance for changes in plate thickness! Il adjustment (thickness adjustment) is necessary not only in the vertical direction but also in the roll width direction (usually done by inserting a liner between rolls divided in the width direction), so adjustment in the roll width direction must be done manually. Adjustment is required, and therefore the effect of automatic sheet thickness adjustment using disc springs is weak, but in the roller die forming apparatus like the example, only one adjustment point is required in response to changes in sheet thickness. , manual adjustment is not required at all, and the effects of the present invention are extremely large.

In addition, not only in the case of the embodiment, but in a roller die forming apparatus, for example, when forming channel steel or channel steel with a lip, the relationship between the plate thickness of the forming material and the forming load is determined for each forming unit. The present invention is easy to apply because it can be determined,
In this respect, it is appropriate to apply the present invention to a roller die forming apparatus.

Next, an example of a method for selecting the above-mentioned spring will be explained.

Figure 7 shows a plate with an outer diameter of 25 mm, an inner diameter of 12.2 mm, and a plate thickness of 1.
6mm, height 2.15mm (i.e. maximum displacement 10.
A load test was conducted on each combination of two disc springs (55mm) facing each other, stacking two disc springs facing each other, stacking two disc springs facing each other, and stacking two disc springs facing each other.The horizontal axis is the spring displacement x, 1! The repulsive force is y. In FIG. 8, the curve is a graph showing the relationship between the molding material plate thickness t and the molding load at R3 of the molding unit (for R3, the bending angle α=6
7.5° (=180”-θ)), and in a forming unit with this plate thickness-forming load curve, for example, eight disc springs are stacked in two layers in four layers as shown in the figure. This combination of disc springs is selected so that the slope of the displacement-repulsion force curve (straight line) P approximates the approximate slope of the plate thickness-forming load curve. When the plate is not threaded, the washer 27 and bracket 22a
A predetermined gap a (Fig. 8) is set to exist between the bottom surface of the recess 22c and the bottom surface of the recess 22c.In this way, no repulsive force is generated until the roll clearance reaches the predetermined value a, and then the spring Since a repulsive force is generated according to the amount of deflection of the plate, the spring characteristic is essentially shown by the broken line P° in Fig. 8, and the plate thickness -
Approximate to the forming load curve. Therefore, when forming using this combination of disc springs, the appropriate roll clearance according to the thickness of the forming material to be passed is automatically obtained, and the forming load at that time is the same as that required for forming the forming material. It's the size.

In addition, in FIG. 9, the curve is a graph showing the plate thickness-forming load curve at R1 of the forming unit, and this R6
In the molding stand, six disc springs 26 are arranged in two stacks in three stages as shown in the figure. The displacement-repulsion force straight line of this combination of disc springs is as shown by P in Fig. 9, and the washer 2 when the plate spring is not threaded is similar to the above.
When the gap at the 7th part is b, the actual spring characteristic is shown by the broken line P.
Thus, a spring characteristic that approximates the plate thickness-forming load curve can be obtained, and by using a disc spring of this combination, an appropriate roll clearance can be automatically obtained.

In addition, in the explanation of FIGS. 8 and 9 above, it is not taken into consideration that the outer radius of the bent part of the formed material (the bending radius on the outer surface side of the bent part) changes depending on the plate thickness. When considering the change in outer radius due to plate thickness, the first
As shown in Figure 0, when the plate thickness increases by δT from T+ to T2, the required roll clearance change amount (flat spring displacement amount) δC is larger than δT, although details are omitted, and δC = δT. /cos(α/2>), so it is desirable to select a spring with a spring coefficient corresponding to this.Specifically, it is desirable to select a spring with a spring coefficient that is smaller than the straight line p(p') in FIGS. (small spring coefficient)
A spring will be used.

Also, depending on where the spring is placed, the change in plate thickness or the amount of displacement of the spring placement area may be expanded or contracted (
(depending on the distance from the fulcrum pin 23), select a spring with a corresponding spring coefficient.

Note that the method of combining disc springs is not limited to combining only disc springs of the same type, but also disc springs with different spring coefficients can be combined. Thereby, it is also possible to further approximate the plate thickness-forming load curve. Figure 11 shows an example of stacking two stacked sheets, one with two sheets facing each other and one with two sheets facing each other. In this case, in the area of small displacement, the disc spring with a small spring coefficient (two sheets facing each other) acts mainly. After this disc spring with a small spring coefficient collapses flat, the disc spring with a large spring coefficient (two stacked facing each other) acts mainly to form a straight line with a steep slope. According to experiments, the spring repulsion force does not change in a polygonal line as shown by a dashed line, but changes in a curve as shown in a solid line.

Further, the locations where the disc springs are arranged are not limited to those of the above embodiments, and various other locations may be considered. In short, it may be any location that is located between the roller holder 17 and the second face plate 11 and receives the entire forming load.

As is clear from the above explanations, the displacement-repulsion curve representing the relationship between spring displacement and spring repulsion approximates the thickness-forming load curve representing the relationship between the thickness of the forming material and the forming load. ``has spring characteristics'' means within the applicable plate thickness range, and not only when the lines on both sides are directly superimposed to form a nearly similar shape;
This includes the case where the shape becomes almost similar when the coordinates of the spring displacement are shifted, as shown by the broken line P'' in FIG. 9, or the case where the shape becomes almost similar when the coordinates of the spring displacement are multiplied by a certain coefficient.

Further, although it is convenient to always have a load cell disposed in order to select an appropriate spring, it is not always necessary.

In addition, although the above embodiment describes the case where it is applied to a roller die forming method, the present invention is not limited to this, and it goes without saying that it can also be applied to a normal cold roll forming method in which forming is performed using upper and lower horizontal rolls. be. In this case, the spring is preferably interposed between the upper surface of the chock that supports the upper roll shaft and the lower surface of the stand cap.

[Effects of the Invention] Since the present invention is configured as described above, the following effects are achieved.

With a configuration in which the forming load is received by a spring, an appropriate roll clearance is automatically created according to the forming load when the sheet is passed through, so there is no need to adjust the sheet N when changing the product sheet thickness.

According to the method of configuring the spring by combining disc springs, it is easy to obtain a spring having a desired displacement-repulsion force curve corresponding to the molding load of each molding stand.

In addition, in the case of a roller die forming apparatus having a structure in which a roller holder supporting the abutting roller is rotatably attached to the movable support plate side in the thickness direction of the corner round part around a fulcrum pin, changes in the plate thickness may occur. Since only one adjustment point is required (that is, only the rotational movement of the roller holder around the fulcrum pin), the present invention is easy to apply and is extremely effective as an automatic plate thickness adjustment means. It is.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of a cold roll forming apparatus showing an embodiment of the method and apparatus of the present invention, and 2nd Uf! i is a front view of the guide stand, Figure 3 is a front view of the drive-only roll stand for P1 to P2, Figure 4 is a front view of the drive-only roll stand for P, ~P6, and Figure 5 is the molding of Rs to Rt. A perspective view of the unit, FIG. 6(a) is an enlarged front view of the abutment roller in FIG. 5, FIG. 6(b) is a side view of the same, FIG. Figures 8 and 9 are diagrams for explaining the method of selecting disc springs; Figure 8 is for forming unit R1, Figure 9 is for forming unit R6,
Fig. 10 is a diagram explaining another method of selecting a disc spring, Fig. 11
The figure is a diagram illustrating yet another method of selecting a disc spring. 2... Material (molding material), 4... Roll stand exclusively for feed drive (feed unit), 5... Molding unit, 8
... first face plate, 11... second face plate (movable support plate),
12... Receiving roller, 13... Side forming roller,
14... Abutment roller, 17... Roller holder,
22... Roller holder receiver, 22a... Buffet, 23... Fulcrum pin, 24... Support mechanism, 25...
・Guide shaft, 25a...Brim, 26...Disc spring, 2
7...Washer, 28...Load cell.

Claims (1)

[Claims] 1. A spring characteristic in which a displacement-repulsion force curve representing the relationship between spring displacement and spring repulsion force approximates a plate thickness-forming load curve representing the relationship between the plate thickness of the molded material and the forming load. A cold roll forming method characterized by receiving the forming load using a spring. 2. A cold roll forming method characterized in that the spring is constructed by combining a plurality of disc springs. 3.Claim 1 on the part of the molding device where the molding load is applied
Or a cold roll forming device characterized by interposing the spring according to 2. 4. The above-mentioned forming apparatus has a plurality of feeding units that only drive the feeding of the material, and a non-driving forming unit that bends and forms the material, which is placed between the feeding units. A cold roll forming apparatus for forming a lightweight section steel having a cross-sectional shape having side portions bent on both sides, the forming unit being in contact with an outer surface near a corner portion of a bottom portion to receive free rotation. A left and right movable roller that can adjust the movement in the width direction of the material, an idling side forming roller that contacts the outer surface of the side part, and an idling abutting roller that contacts the inner radius of the corner part. 4. The cold roll forming apparatus according to claim 3, wherein the cold roll forming apparatus is configured such that the set is attached to the support plate via a roller holder so that the movement can be adjusted integrally. 5. A roller holder that supports the abutting roller is attached to the movable support plate so as to be rotatable in the thickness direction of the corner rounded portion about a fulcrum pin perpendicular to the material advancing direction, and the roller holder and the movable support 5. The cold roll forming apparatus according to claim 4, wherein the spring according to claim 1 or 3 is interposed in a portion that receives a forming load between the cold roll forming apparatus and the plate.