JP2017100188A - Manufacturing method and manufacturing device for manufacturing steel plate having embossment shape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method and a manufacturing device which can mold a steel plate having an embossment shape of a sharp appearance while suppressing breakage thereof.SOLUTION: A steel plate 9 is preliminarily molded into a wavy shape in such a manner that the steel plate 9 is passed between a pair of first rolls 1, and a thickness direction pressure is applied onto each portion of the steel plate 9. Next, the steel plate 9 after preliminary molding is passed between a pair of second rolls 2, and the steel plate 9 having a wavy shape is substantially molded to a prescribed embossment shape. The embossment shape is so called a rectangular wavy shape in which plural concave strip parts having a U-shaped cross section are arranged with an interval therebetween.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method and an apparatus for manufacturing a steel plate having an embossed shape, and more particularly, to a method and an apparatus for manufacturing a steel plate having a predetermined embossed shape by performing preforming and main forming.

  Patent Document 1 describes a technique for forming an emboss on a metal strip.

  In this technique, an emboss is formed in a metal strip by passing the metal strip between a pair of rolls provided in the emboss roll.

JP 2002-239629 A

  With the conventional technique described in Patent Document 1, it is difficult to obtain an emboss having a sharp appearance. This is because, in the conventional technology, unless the embossed holes are formed with a shallow slope, the strain tends to concentrate on a part of the metal band, causing damage such as cracks.

  An object of the present invention is to provide a manufacturing method and a manufacturing apparatus capable of forming a steel plate having an embossed shape with a sharp appearance and suppressing the occurrence of breakage during forming. .

  A method for producing a steel plate having an embossed shape according to one aspect of the present invention includes passing a steel plate between a pair of first rolls, and applying a pressure to each part of the steel plate to stretch the steel plate, thereby providing a plurality of preliminary grooves. A preforming step for giving a predetermined corrugated shape with a portion positioned at a distance in one direction, and passing the steel plate with the corrugated shape between a pair of second rolls; A main forming step of providing a predetermined embossed shape in which a plurality of concave strip portions having a U-shaped cross section are positioned at a distance in the one direction by bending by applying pressure. The preliminary groove portion and the concave portion correspond to each other one-to-one, and the depth of the preliminary groove portion is the same as the depth of the corresponding concave portion.

  According to another aspect of the present invention, there is provided a method for manufacturing a steel plate having an embossed shape, wherein a plurality of preliminary recesses are formed on the steel plate while passing the steel plate between a pair of first rolls and applying pressure to various portions of the steel plate. A preforming step for providing a predetermined corrugated shape in which strips are located at a distance in one direction, and passing the steel plate provided with the corrugated shape between a pair of second rolls. And a main forming step in which a plurality of concave strips having a U-shaped cross section are given a predetermined embossed shape with a distance in the one direction by bending the steel sheet with pressure. The preliminary groove portion and the concave portion correspond one-to-one, and the depth of the preliminary groove portion is larger than the depth of the corresponding concave portion.

  The depth of the concave ridge is 2 mm to 4 mm, and the depth of the preliminary concave ridge is larger by 0.5 mm to 1.5 mm than the corresponding depth of the concave ridge, and 5 mm or less. It is preferable that

  An apparatus for manufacturing a steel sheet having an embossed shape according to one aspect of the present invention includes a pair of first rolls that preform a steel sheet and give the steel sheet a predetermined corrugated shape, and the steel sheet after the preforming is fully formed. And a pair of second rolls that give the steel plate a predetermined embossed shape. The pair of first rolls is a mold structure that gives the corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction on the steel sheet by extending the steel sheet by applying pressure to each part of the steel sheet. Have The pair of second rolls has a die structure that gives the embossed shape in which a plurality of concave strip portions having a U-shaped cross section are positioned at a distance in the one direction on the steel plate after the preforming. The preliminary groove portion and the concave portion correspond to each other one-to-one, and the depth of the preliminary groove portion is the same as the depth of the corresponding concave portion.

  An apparatus for producing a steel plate having an embossed shape according to another aspect of the present invention includes a pair of first rolls that preform a steel plate to give the steel plate a predetermined corrugated shape, and the steel plate after the preforming. A pair of second rolls that are shaped to give the steel plate a predetermined embossed shape. The pair of first rolls is a mold structure that gives the corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction on the steel sheet by extending the steel sheet by applying pressure to each part of the steel sheet. Have The pair of second rolls has a die structure that gives the embossed shape in which a plurality of concave strip portions having a U-shaped cross section are positioned at a distance in the one direction on the steel plate after the preforming. The preliminary groove portion and the concave portion correspond one-to-one, and the depth of the preliminary groove portion is larger than the depth of the corresponding concave portion.

  The method for producing a steel plate having an embossed shape according to the present invention can form an embossed shape having a sharp appearance, and has an effect of suppressing breakage during forming.

  The apparatus for producing a steel plate having an embossed shape according to the present invention can form an embossed shape having a sharp appearance, and has an effect of suppressing breakage during forming.

FIG. 1 is a side view schematically showing the manufacturing apparatus of the first embodiment. FIG. 2 is a front view schematically showing a pair of first rolls included in the manufacturing apparatus same as above. FIG. 3 is an enlarged view of a portion P in FIG. FIG. 4 is a front view schematically showing a pair of second rolls included in the production apparatus. FIG. 5 is an enlarged view of a portion Q in FIG. FIG. 6 is an explanatory diagram showing the corrugated shape and the embossed shape in an overlapping manner. FIG. 7A is an explanatory view showing a corrugated shape set at an inclination angle α = 25 °, and FIG. 7B is an explanatory view showing an embossed shape formed through the corrugated shape of FIG. 7A. 8A is a diagram showing a strain distribution generated in the corrugated shape of FIG. 7A, and FIG. 8B is a diagram showing a strain distribution generated in the embossed shape of FIG. 7B. FIG. 9A is an explanatory view showing a corrugated shape set at an inclination angle α = 38 °, and FIG. 9B is an explanatory view showing an embossed shape formed through the corrugated shape of FIG. 9A. 10A is a diagram illustrating a strain distribution generated in the corrugated shape of FIG. 9A, and FIG. 10B is a diagram illustrating a strain distribution generated in the embossed shape of FIG. 9B. FIG. 11A is an explanatory view showing a corrugated shape set at an inclination angle α = 53 °, and FIG. 11B is an explanatory view showing an embossed shape formed through the corrugated shape of FIG. 11A. 12A is a diagram illustrating a strain distribution generated in the corrugated shape of FIG. 11A, and FIG. 12B is a diagram illustrating a strain distribution generated in the embossed shape of FIG. 11B. FIG. 13 is a view showing a steel sheet formed into an embossed shape by a single roll forming. FIG. 14 is a diagram showing a strain distribution of the steel plate of FIG. FIG. 15: is a front view which shows roughly the principal part of the preforming machine with which the manufacturing apparatus of 2nd embodiment is provided. FIG. 16: is a front view which shows a mode that a preforming is performed with the manufacturing apparatus same as the above. FIG. 17: is a front view which shows roughly the principal part of this molding machine with which the manufacturing apparatus same as the above is provided. FIG. 18 is a front view schematically showing how the main forming is performed by the manufacturing apparatus same as above. FIG. 19 is a diagram showing an analysis model of preforming performed by the manufacturing apparatus same as above. FIG. 20A is a diagram illustrating a strain distribution generated in a steel sheet after preforming under the condition of R1 = R2 = 3.5 mm, and FIG. 20B is a diagram illustrating a strain distribution generated after further forming the steel sheet in FIG. 20A. It is. FIG. 21A is a diagram illustrating a strain distribution generated in a steel sheet after preforming under the condition of R1 = R2 = 3.0 mm, and FIG. 21B is a diagram illustrating a strain distribution generated after further forming the steel sheet in FIG. 21A. It is. FIG. 22A is a diagram showing a strain distribution generated in a steel sheet after preforming under the condition of R1 = R2 = 2.5 mm, and FIG. 22B is a diagram showing a strain distribution generated after the steel sheet of FIG. 22A is further fully formed. It is. FIG. 23A is a diagram showing a strain distribution generated in a steel sheet after preforming under the condition of R1 = R2 = 1.5 mm, and FIG. 23B is a diagram showing a strain distribution generated after the steel sheet in FIG. 23A is further fully formed. It is. FIG. 24 is a diagram showing a strain distribution of a steel sheet formed into a similar embossed shape by a single forming. FIG. 25A is a graph showing the relationship between the stroke amount under the conditions of β = 80 ° and D2 = 3.0 mm and the maximum strain after the main forming, and FIG. 25B shows β = 70 ° and D2 = 3.0 mm. FIG. 25A is a graph showing the relationship between the stroke amount under the conditions and the maximum strain after the main molding, and FIG. 25A shows the stroke amount and the maximum strain after the main molding under the conditions of β = 60 ° and D2 = 3.0 mm. It is a graph which shows a relationship. FIG. 26 is a graph showing the relationship between the stroke amount and the maximum strain after the main molding under the conditions of β = 70 ° and D2 = 2.0 mm. FIG. 27 is a graph showing the relationship between the stroke amount and the maximum strain after the main forming under the conditions of β = 60 ° and D2 = 4.0 mm.

(First embodiment)
In FIG. 1, the manufacturing apparatus of the steel plate which has the embossed shape of 1st embodiment is shown.

  In the following, a steel plate having an embossed shape is referred to as an “embossed steel plate”, a device for manufacturing the steel plate is simply referred to as a “manufacturing device”, and a method for manufacturing the same is simply referred to as a “manufacturing method”. The embossed steel sheet of this embodiment is used for various uses such as siding.

  The manufacturing apparatus of the present embodiment sequentially performs the preforming and the main forming on the strip-shaped steel plate 9, thereby suppressing the breakage of the steel plate 9 and making the steel plate 9 a sharp emboss shape F2 (see the solid line in FIG. 6). It is an apparatus which molds into.

  The manufacturing apparatus according to the present embodiment is preformed with respect to an uncoiler 81 for feeding the strip-shaped steel plate 9, a side guide 82 for guiding the steel plate 9 fed from the uncoiler 81, and a thin plate-like steel plate 9 fed from the uncoiler 81. A pre-forming machine 83 that performs the main forming process, a main forming machine 84 that performs the main forming on the pre-formed steel sheet 9, and a drawer roll 85 that further feeds the main formed steel sheet 9.

  The uncoiler 81, the side guide 82, the preliminary molding machine 83, the main molding machine 84, and the drawer roll 85 are arranged in this order along the feeding direction indicated by the white arrow in the drawing. The steel plate 9 sent out from the uncoiler 81 is made of a flat strip-like coated steel plate. The term “flat” used in the present text is not limited to a strictly flat meaning, but includes a case where it is substantially flat.

  The preforming machine 83 includes a pair of upper and lower first rolls 1. Below, the 1st roll 1 located in an upper side among a pair of 1st rolls 1 is called an "upper 1st roll", and the code | symbol 1a is attached | subjected. Of the pair of first rolls 1, the first roll 1 positioned on the lower side is referred to as a “lower first roll” and is denoted by reference numeral 1 b.

  An upper mold 11a for preforming is provided on the outermost layer of the upper first roll 1a. A lower mold 11b for preforming is provided on the outermost layer of the lower first roll 1b.

  Both the upper mold 11a and the lower mold 11b for preforming are molds having continuous gentle irregularities such as so-called sine waves (see FIG. 3), and the steel plate 9 is moved in the vertical direction (steel plate). The steel sheet 9 is roll-formed until it reaches a predetermined corrugated shape F1 (see the chain line in FIG. 6). That is, the upper die 11a and the lower die 11b constitute a die structure 11 for preforming the steel plate 9 into the corrugated shape F1.

  The main molding machine 84 includes a pair of upper and lower second rolls 2. Of the pair of second rolls 2, the second roll 2 positioned on the upper side is referred to as an “upper second roll” and is denoted by reference numeral 2 a. Of the pair of second rolls 2, the second roll 2 positioned on the lower side is referred to as a “lower second roll” and is denoted by reference numeral 2 b.

  An upper mold 21a for main forming is provided on the outermost layer of the upper second roll 2a. Similarly, the lower mold 21b for main molding is provided on the outermost layer of the lower second roll 2b.

  Both the upper mold 21a and the lower mold 21b for main molding are molds having continuous right and left irregularities such as so-called rectangular waves (see FIG. 5). Then, the steel sheet 9 having the corrugated shape F1 is roll-formed until reaching a predetermined emboss F2. That is, the upper die 21a and the lower die 21b constitute a die structure 21 for main forming the steel plate 9 into a predetermined emboss shape F2 (see the solid line in FIG. 6).

  The embossed steel plate 9 is obtained by cutting the steel plate 9 formed into the embossed shape F2 into a predetermined dimension in a later step. The obtained embossed steel sheet is used, for example, as metal siding. Alternatively, a core material and a sheet material which are laminated in this order in a subsequent process on the obtained embossed steel sheet and cut into a predetermined dimension may be used as metal siding. The core material is a heat insulating material using, for example, a foamed resin, and the sheet material is, for example, a metal panel or a backing paper.

  In the former case, the finally obtained metal siding is a coated steel sheet formed into an embossed shape F2. In the latter case, the finally obtained metal siding is a sandwich panel in which a core material is sandwiched between a coated steel sheet and a sheet material formed into an embossed shape F2.

  Next, the corrugated shape F1 and the embossed shape F2 will be described in more detail.

  In FIG. 6, the corrugated shape F1 and the embossed shape F2 are shown in an overlapping manner. The chain line in the figure is the corrugated shape F1 steel plate 9, and the solid line in the figure is the embossed shape F2 steel plate 9.

  As shown in the drawing, the height of the unevenness (the height in the vertical direction) is the same in the steel plate 9 at the stage formed into the corrugated shape F1 and the steel plate 9 formed into the embossed shape F2. The term “same” used in the present text is not limited to the same in a strict sense, but includes a case where they are substantially the same.

  The corrugated shape F1 of the present embodiment is a shape in which the flat steel plate 9 is rolled in the vertical direction between the upper die 11a and the lower die 11b, and is stretched and bent. It continuously has gentle irregularities such as so-called sine waves.

  The steel plate 9 formed into the corrugated shape F1 is curved in an arc shape so as to project in a direction opposite to the predetermined direction (downward) from the preliminary protruding portion 31 curved in an arc shape so as to protrude in a predetermined direction (upward). The preliminary recessed streak portions 32 have a structure in which they are alternately formed via the connecting walls 33.

  The connecting wall 33 is an inclined portion that smoothly connects the adjacent preliminary ridge portions 31 and the preliminary concave ridge portions 32, and is inclined with respect to a plane (horizontal plane) orthogonal to the thickness direction (vertical direction) of the steel plate 9. Only tilted and located. The inclination angle α is 45 °, for example.

  The embossed shape F2 of the present embodiment is a shape formed by rolling the steel plate 9 of the corrugated shape F1 in the vertical direction between the upper die 21a and the lower die 21b and applying bending. It has sharp irregularities like a so-called rectangular wave continuously.

  The steel plate 9 formed into the embossed shape F2 has a shape in which a plurality of concave strip portions 41 having a U-shaped shape are arranged at a predetermined distance along one direction 900 (the width direction of the steel plate 9). is there.

  Each concave strip 41 includes a flat bottom wall 411 and a pair of vertical walls 412 that rise from both ends of the bottom wall 411 in one direction, and has an opening on the opposite side (upper side) of the bottom wall 411. A flat upper wall 42 is formed between a pair of concave strips 41 adjacent in one direction.

  The top wall 42 is parallel to the bottom wall 411 of the concave strip 41 adjacent thereto. The term “parallel” used in the present text is not limited to parallel in a strict sense, but includes a case of being substantially parallel.

  According to the manufacturing apparatus of the present embodiment, the steel plate 9 is first stretched and formed into the corrugated shape F1, and then bent until reaching the embossed shape F2. It is possible to obtain an embossed steel plate with a good appearance.

  In order to suppress breakage during molding more effectively, it is preferable to set the inclination angle α of the connecting wall 33 of the corrugated shape F1 to a range of 20 ° or more and within 60 °. A more preferable setting is to set the inclination angle α within a range of 30 ° or more and 45 ° or less.

  Next, the strain distribution of the steel plate 9 obtained by numerical analysis will be described. 7 to 12 show the strain distribution of the steel sheet 9 generated by the corrugated shape F1 and the embossed shape F2 by setting a plurality of inclination angles α. The thickness of the steel plate 9 is set at 0.27 mm. FIGS. 13 and 14 show a strain distribution when the steel plate 9 is formed into the embossed shape F2 by a single roll forming as a comparative example.

  As shown in FIGS. 13 and 14, when the embossed shape F <b> 2 is formed by a single roll forming, pulling and bending occur at the shoulder portion 45 at the same time, and tensile strain and bending strain are superimposed. The thickness of the portion 45 is remarkably reduced, and breakage such as cracking and breaking is likely to occur.

  On the other hand, as shown in FIGS. 7 to 12, the strain is suppressed from being concentrated on the shoulder portion 45 by performing the preliminary molding before the main molding.

  The example shown in FIGS. 7 and 8 is an example in which the inclination angle α of the corrugated shape F1 steel plate 9 is set to 25 °, and the curvature radius of the shoulder portion 35 is 10.0 mm. This curvature radius is larger than the curvature radius (= 1.0 mm) of the shoulder portion 45 of the embossed shape F2.

  The example shown in FIGS. 9 and 10 is an example in which the inclination angle α of the corrugated shape F1 steel plate 9 is set to 38 °, and the curvature radius of the shoulder 35 is 3.0 mm. This curvature radius is larger than the curvature radius (= 1.0 mm) of the shoulder portion 45 of the embossed shape F2.

  The example shown in FIGS. 11 and 12 is an example in which the inclination angle α of the corrugated shape F1 steel sheet 9 is set to 53 °, and the curvature radius of the shoulder 35 is 1.5 mm. This curvature radius is larger than the curvature radius (= 1.0 mm) of the shoulder portion 45 of the embossed shape F2.

  From the above calculation results, it can be seen that it is less likely to cause damage when the steel plate 9 is formed into the embossed shape F2 by the pre-forming and the main forming than when the steel plate 9 is formed into the embossed shape F2 by one roll forming.

  Further, it can be seen that even when the preforming and the main forming are performed, the breakage is less likely to occur when the inclination angle α is set in the range of 30 ° to 45 °. When the inclination angle α is smaller than 30 °, strain concentration tends to occur at the shoulder 45 during the main forming. When the inclination angle α exceeds 45 °, strain concentration tends to occur in the shoulder portion 35 during the preforming.

  In addition, when the tolerance | permissible_range of thickness reduction of the shoulder part 45 is less than 50%, you may set inclination-angle (alpha) to the range which is 20 degrees or more and 60 degrees or less.

  Similar results are confirmed in experiments.

(Second embodiment)
Next, the manufacturing apparatus and manufacturing method of 2nd embodiment are demonstrated based on FIGS.

  In addition, about the structure similar to 1st embodiment among the structures of this embodiment, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. In the following, the configuration different from the first embodiment will be described in detail.

  The manufacturing apparatus of this embodiment includes an upper mold 11a and a lower mold 11b for preforming whose main parts are shown in FIGS. 15 and 16, and further, for main molding whose main parts are shown in FIGS. The upper mold 21a and the lower mold 21b are provided.

  The upper mold 11 a for preforming has a plurality of convex portions 115 a having a circular arc cross section that press against the steel plate 9 in the thickness direction (downward) at a distance in one direction 900. The radius R1 of the convex portion 115a is, for example, 3.5 mm.

  The lower mold 11b for preforming has a plurality of convex portions 115b having a circular arc cross section that press against the steel plate 9 in the thickness direction (upward) at a distance in one direction 900. The radius R2 of the convex portion 115b is, for example, 3.5 mm.

  In one direction 900, the convex portions 115a of the upper mold 11a and the convex portions 115b of the lower mold 11b are alternately positioned with a predetermined pitch P1. The predetermined pitch P1 may be different between the adjacent convex portions 115a and 115b, or may be the same.

  In the preforming step, the upper convex portion 115a hits the upper surface of the steel plate 9, and the lower convex portion 115b hits the lower surface of the steel plate 9, so that the upper convex portion 115a is shown by a white arrow in FIG. The portion 115a moves relative to the lower convex portion 115b downward. The stroke amount S1 with which the upper convex portion 115a relatively moves downward is, for example, 4.5 mm.

  As shown in FIG. 16, the portion of the steel plate 9 against which the upper convex portion 115 a is pressed becomes a preliminary concave portion 32 that is recessed downward in an arc shape. The portion of the steel plate 9 where the lower convex portion 115b is pressed becomes the preliminary convex strip portion 31 protruding upward in an arc shape.

  In the pre-forming step, the entire steel plate 9 is uniformly stretched and the entire steel plate 9 is gently bent so that the pre-recessed ridge portion 32 and the pre-protruded ridge portion 31 are in one direction 900. A smooth wave shape F1 like a sine wave, which is alternately arranged in FIG. In one direction 900, the length of the steel plate 9 formed into the corrugated shape F1 is substantially the same as the length of the flat steel plate 9 before the preforming.

  In the corrugated shape F1, the depth D1 of the preliminary recess 32 is equal to the stroke amount S1 in the preliminary molding step, for example, 4.5 mm.

  As shown in FIGS. 17 and 18, the upper mold 21 a for main molding is a rectangular wave in which convex portions 215 a having a U-shaped cross section and concave portions 217 a having a U-shaped cross section are alternately provided in one direction 900. The cross-sectional shape is as follows.

  The lower mold 21b for main molding has a cross-sectional shape like a rectangular wave in which convex portions 215b having a U-shaped cross section and concave portions 217b having a U-shaped cross section are alternately provided in one direction 900.

  The upper mold 21a and the lower mold 21b have dimensions that match each other.

  The convex portion 215a of the upper mold 21a has a one-to-one correspondence with the concave portion 217b of the lower mold 21b. Corresponding convex portions 215a and concave portions 217b are in a positional relationship opposite to each other in the vertical direction, and have dimensions that match each other.

  The concave portion 217a of the upper mold 21a has a one-to-one correspondence with the convex portion 215b of the lower mold 21b. Corresponding concave portions 217a and convex portions 215b are in a positional relationship facing each other in the vertical direction, and have dimensional shapes that match each other.

  Furthermore, the convex portion 215a of the upper mold 21a for main molding has a one-to-one correspondence with the convex portion 115a of the upper mold 11a for preforming. The convex portion 215b having a U-shaped cross section included in the lower mold 21b for main molding has a one-to-one correspondence with the convex portion 115b included in the lower mold 11b for preforming.

  In one direction 900, the convex portions 215a of the upper mold 21a and the convex portions 215b of the lower mold 21b are alternately positioned with a predetermined pitch P2. The pitch P2 between the convex portions 215a and 215b in the main molding step is the same as the pitch P1 between the convex portions 115a and 115b in the preforming step corresponding to the convex portions 215a and 215b, and is, for example, 7 mm.

  In the main forming step, the upper convex portion 215a hits the upper surface of the steel plate 9 formed into the corrugated shape F1, and the lower convex portion 215b hits the lower surface of the steel plate 9 from the state shown in FIG. As shown by white arrows, the upper mold 21a moves relative to the lower mold 21b downward. The stroke amount by which the upper mold 21a relatively moves downward is, for example, 1.5 mm.

  At this time, the top portion 312 of the preliminary ridge portion 31 included in the corrugated steel sheet 9 having the corrugated shape F1 hits the concave portion 217a of the upper mold 21a and is pushed downward, and the top 322 of the preliminary concave portion 32 included in the steel plate 9 is removed. A portion 324 that approaches the preliminary ridge portion 31 hits a corner portion of the convex portion 215a of the upper mold 21a and is pushed downward.

  Similarly, the top portion 322 of the preliminary concave portion 32 included in the corrugated F1 steel plate 9 presses against the concave portion 217b of the lower mold 21b, and the preliminary convex portion 31 included in the steel plate 9 is spared from the top portion 312. The portion 314 approaching the concave stripe portion 32 presses against the corner portion of the convex portion 215b of the lower mold 21b.

  Thereby, the steel plate 9 preformed into the corrugated shape F1 is finally formed into an embossed shape F2 as shown in FIG. In one direction 900, the length of the steel plate 9 formed into the embossed shape F2 is substantially the same as the length of the steel plate 9 before and after the preforming.

  The concave portion 41 of the steel plate 9 having the embossed shape F2 is rolled up and down between the convex portion 215a of the upper die 21a and the concave portion 217b of the lower die 21b, and is subjected to bending so that the cross section It is a part that is molded in a U shape.

  The plurality of concave strip portions 41 included in the steel plate 9 having the embossed shape F2 correspond one-to-one with the plurality of preliminary concave strip portions 32 included in the steel plate 9 having the corrugated shape F1. The depth D2 of the concave stripe portion 41 is smaller than the depth D1 of the corresponding preliminary concave stripe portion 32. That is, when the steel plate 9 at the stage preliminarily formed into the corrugated shape F1 is compared with the steel plate 9 at the stage finally formed into the embossed shape F2, the unevenness is formed deeper in the pre-forming stage.

  According to the manufacturing apparatus of the present embodiment, the steel plate 9 is first stretched uniformly and greatly into a corrugated shape F1, and then bent up to the embossed shape F2 while being crushed in the vertical direction. It is possible to suppress damage due to concentration of strain.

  In addition, in the main forming step, when rolling the steel sheet 9 having the corrugated shape F1 between the upper mold 21a and the lower mold 21b, the upper and lower apexes 312 and 322 of the steel sheet 9 are pushed in the vertical direction. It is. Of the preliminary ridge portion 31 of the steel plate 9, a portion 314 bent by hitting the corner portion of the lower mold 21b and a portion 324 bent by hitting the corner portion of the upper die 21a tend to reduce thickness due to concentration of strain. Although it is a part, compressive strain is given to these parts 314 and 324 from the tops 312 and 322 side, and when the material flows, concentration of strain and reduction in thickness are suppressed.

  Next, the strain distribution of the steel plate 9 obtained by numerical analysis will be described.

  The analysis here is performed by using the model shown in FIG. 19 and changing the radii R1 and R2 of the convex portions 115a and 115b in the preforming in a plurality of stages, and further, the stroke amount S1 of the convex portion 115a (that is, the preliminary groove). The depth D1) of the portion, the depth D2 of the concave strip 41 after the main forming, and the inclination angle β of the vertical wall 412 were changed in a plurality of stages. The pitch P1 between the convex portions 115a and 115b was fixed at 7 mm.

  The results shown in FIGS. 20A to 23B are obtained by calculating the strain distribution of the steel sheet 9 generated by the corrugated shape F1 and the embossed shape F2 by changing the radii R1 and R2 between 3.5 and 1.5 mm. .

  FIG. 24 shows, as a comparative example, a strain distribution when the steel plate 9 is formed into a similar embossed shape F2 by a single forming (only main forming) as in the prior art. As shown in FIG. 24, when the embossed shape F2 is formed by a single molding, strain concentrates on the rectangular wave shoulder and the vertical wall, and breakage or the like is likely to occur. In the result of FIG. 24, the maximum strain is 57.5%.

  On the other hand, as shown in FIG. 20A to FIG. 23B, the strain is suppressed from being concentrated on a specific portion of the steel plate 9 by performing the preforming before the main forming.

  20A and 20B, the conditions in the pre-forming are set to radius R1 = R2 = 3.5 mm and the stroke amount S1 = 4.5 mm, and the conditions in the main forming are the depth D2 = 3 mm and the inclination angle β = The result when set to 70 ° is shown. In this case, the maximum strain in the embossed shape F2 in FIG. 20B is 41.4%.

  Similarly, in FIG. 21A and FIG. 21B, the conditions in the pre-forming are set to radius R1 = R2 = 3.0 mm and the stroke amount S1 = 4.5 mm, and the conditions in the main forming are the depth D2 = 3 mm, the inclination The results when the angle β is set to 70 ° are shown. In this case, the maximum strain in the embossed shape F2 in FIG. 21B is 35.0%.

  22A and 22B, the conditions for the pre-forming are set to radius R1 = R2 = 2.5 mm and the stroke amount S1 = 4.5 mm, and the conditions for the main forming are the depth D2 = 3 mm and the inclination angle β = The result when set to 70 ° is shown. In this case, the maximum strain in the embossed shape F2 in FIG. 22B is 32.5%.

  In FIG. 23A and FIG. 23B, the conditions in the pre-forming are set to radius R1 = R2 = 1.5 mm and the stroke amount S1 = 4.5 mm, and the conditions in the main forming are the depth D2 = 3 mm and the inclination angle β = The result when set to 70 ° is shown. In this case, the maximum strain in the embossed shape F2 in FIG. 23B is 38.8%.

  From the above analysis results, the steel plate 9 is once stretched to the corrugated shape F1 by pre-forming rather than forming the steel plate 9 to the embossed shape F2 by one forming as shown in FIG. It can be seen that the concentration of strain can be suppressed by forming the rectangular wave type embossed shape F2 while crushing 9 upward and downward.

  Further, from the above analysis results, it can be seen that when the radii R1 and R2 of the convex portions 115a and 115b in the preforming change, the strain concentration portion of the corrugated shape F1 steel sheet 9 changes. In general, as the radii R1 and R2 are reduced, the strain concentration portion is closer to the top portions 312 and 322 of the preliminary projection 31 and the preliminary recess 32.

  Therefore, if the strain concentration site in the corrugated shape F1 of the steel plate 9 is provided so as to be away from the corner portion (portion that becomes a rectangular corrugated shoulder) in the emboss shape F2, the specific site of the steel plate 9 after the main forming is provided. It is possible to prevent the strain from concentrating on.

  For example, when the corrugated shape F1 obtained by preforming is a shape close to a sine wave, distortion due to rolling tends to be concentrated in the intermediate region between the convex and concave portions, but the corrugated shape obtained by preforming When the shape F1 is a shape in which a linear portion exists at a large ratio between the convex portion and the concave portion, the strain due to the rolling process tends to concentrate on the convex portion and the concave portion. In the latter case, in the main forming after the pre-forming, by rolling the linear portion of the corrugated shape F1, the steel plate 9 formed into the embossed shape F2 is strained throughout, and the workability is improved. Contributes to improvement.

  Tables 1 and 2 below show the maximum strain and the reduction rate in the embossed shape F2 after the main molding when the analysis was performed by changing each condition stepwise. The value of the reduction rate indicates a rate at which the maximum strain is reduced by performing the pre-forming with the maximum strain when the steel plate 9 is formed into the embossed shape F2 (comparative example) only by the main forming as 1.

  The graphs shown in FIGS. 25A to 25C are graphs summarizing how the maximum strain after the main forming changes according to the change in the stroke amount S1 in the pre-forming.

  FIG. 25A shows the case where the inclination angle β of the vertical wall 412 after the main forming is 80 ° and the depth D2 of the concave strip portion 41 is 3.0 mm. FIG. 25B shows a case where the inclination angle β after main molding is 70 ° and the depth D2 of the concave stripe portion 41 is 3.0 mm. FIG. 25C shows the case where the inclination angle β after the main forming is 60 ° and the depth D2 of the concave strip portion 41 is 3.0 mm.

  Also from these graphs, the stroke amount S1 (that is, the depth D1 of the preliminary concave portion 32) in the preliminary molding is set to be larger than the depth D2 (= 3.0 mm) of the concave portion 41 after the main molding. Sometimes it can be seen that the maximum strain is reduced. In addition, when the inclination angle β = 80 °, 70 °, or 60 °, the stroke amount S1 (depth D1 of the preliminary concave ridge portion 32) is set within the range of 3.5 to 4.5 mm. That is, it can be seen that the maximum strain is effectively reduced when the depth D2 of the recess 41 is set within a range exceeding 0.5 to 1.5 mm. Furthermore, when the stroke amount S1 (depth D1) is set within a range that exceeds the depth D2 of the groove 41 by 1.0 to 1.5 mm, the maximum strain may be more effectively reduced. Recognize.

  The graph shown in FIG. 26 shows that after the main forming, the inclination angle β after the main forming is 70 ° and the depth D2 of the concave portion 41 is 2.0 mm, depending on the change in the stroke amount S1 in the pre-forming. It is the graph which summarized how the maximum strain value of changed. As shown in Table 2, when the inclination angle β is 70 ° and the depth D2 is 2.0 mm, the maximum strain is 38.4% in the comparative example in which only the main forming is performed.

  From this graph, even in the case of D2 = 2.0 mm, the stroke amount S1 (depth D1 of the preliminary concave stripe portion 32) is within the range exceeding the depth D2 of the concave stripe portion 41 by 0.5 to 1.5 mm (that is, It can be seen that the maximum strain is effectively reduced when set within the range of 2.5-3.5 mm. Furthermore, the stroke amount S1 (depth D1 of the preliminary groove portion 32) is within a range exceeding the depth D2 of the groove portion 41 by 1.0 to 1.5 mm (that is, within a range of 3.0 to 3.5 mm). It can be seen that the maximum strain is more effectively reduced when set at).

  The graph shown in FIG. 27 shows that after the main forming according to the change in the stroke amount S1 in the pre-forming, when the inclination angle β after the main forming is 60 ° and the depth D2 of the concave portion 41 is 4.0 mm. 6 is a graph summarizing how the maximum strain of the material changes. As shown in Table 2, when the inclination angle β is 60 ° and the depth D2 is 4.0 mm, the maximum strain is 66.1% in the comparative example in which only the main forming is performed.

  From this graph, even in the case of D2 = 4.0 mm, the stroke amount S1 (depth D1 of the preliminary concave ridge portion 32) is within a range exceeding the depth D2 of the concave ridge portion 41 by 0.5 to 1.0 mm (that is, It can be seen that the maximum strain is effectively reduced when set within the range of 4.5-5.0 mm. Note that the maximum strain greatly increases when the stroke amount S1 exceeds 5 mm due to molding limitations.

  In summary, when the depth D2 of the groove 41 is within the range of 2.0 to 4.0 mm, the stroke amount S1 (depth D1 of the preliminary groove 32) is the depth of the groove 41. When D2 exceeds 0.5 to 1.5 mm (more preferably 1.0 to 1.5 mm) and is set within a range of 5 mm or less, the maximum strain after the main molding is effectively reduced. .

  Further, from the results shown in Tables 1 and 2, when the inclination angle α after the preforming is set within a range of 30 to 50 ° (more preferably 34.2 to 41.4 °), a large reduction rate. It can be seen that

  Similar results are confirmed in experiments.

  As described above, as described with reference to the accompanying drawings, the manufacturing method of the first embodiment includes a preforming step and a main forming step.

  In the preforming process, the steel plate 9 is passed between the pair of first rolls 1 and a plurality of preliminary concave portions 32 are spaced apart in one direction 900 on the steel plate 9 while applying pressure to various portions of the steel plate 9 and extending it. This is a step of providing a predetermined corrugated shape F1 positioned at a position.

  In the main forming step, the steel plate 9 provided with the corrugated shape F1 is passed between the pair of second rolls 2 and is bent by applying pressure to various portions of the steel plate 9 so that the steel plate 9 has a U-shaped cross section. This is a step of providing a predetermined embossed shape F2 in which a plurality of concave strip portions 41 are positioned at a distance in one direction 900.

  The preliminary groove portions 32 and the concave groove portions 41 correspond one-to-one, and the depth D1 of the preliminary groove portions 32 is the same as the depth D2 of the corresponding concave groove portions 41.

  Therefore, according to this manufacturing method, the pre-forming step and the main step are sequentially performed on the flat steel plate 9, and the steel plate 9 is uniformly stretched in the pre-forming step to form the corrugated shape F1. Since it is bent into the embossed shape F2 having the same depth, the steel plate 9 can be formed into an embossed shape F2 having a sharp appearance while suppressing the concentration of strain on a specific portion of the steel plate 9 during forming.

  Moreover, the manufacturing method of the second embodiment includes a preforming step and a main forming step.

  In the pre-forming step, the steel plate 9 is passed between the pair of first rolls 1 and the steel plate 9 is stretched by applying pressure to various portions of the steel plate 9 so that a plurality of preliminary concave portions are spaced apart in one direction 900. This is a step of providing a predetermined corrugated shape F1.

  In the main forming step, the steel plate 9 provided with the corrugated shape F1 is passed between the pair of second rolls 2 and is bent by applying pressure to various portions of the steel plate 9 so that the steel plate 9 has a U-shaped cross section. This is a step of providing a predetermined embossed shape F2 in which a plurality of concave strip portions 41 are positioned at a distance in one direction 900.

  The preliminary ridge portions 32 and the concave ridge portions 41 correspond one to one, and the depth D1 of the preliminary ridge portions 32 is larger than the depth D2 of the corresponding concave ridge portions 41.

  Therefore, according to this manufacturing method, the preforming step and the main step are sequentially performed on the flat steel plate 9, and the steel plate 9 is uniformly extended in the preforming step to form the corrugated shape F1. Since it is bent into a shallow embossed shape F2, the steel plate 9 can be formed into an embossed shape F2 having a sharp appearance while suppressing the concentration of strain at a specific portion of the steel plate 9 during forming.

  In the manufacturing method according to the second embodiment, the depth D2 of the concave stripe portion 41 is 2 mm to 4 mm, and the depth D1 of the preliminary concave stripe portion 32 is larger than the depth D2 of the corresponding concave stripe portion 41. It is preferably 0.5 mm to 1.5 mm and 5 mm or less.

  By setting the depths D1 and D2 in this way, it is possible to effectively suppress the strain from being concentrated on a specific portion of the steel plate 9 after the main forming.

  Moreover, the manufacturing apparatus of 1st embodiment carries out the main shaping | molding of the steel plate 9 after a pair of 1st roll 1 which preforms the steel plate 9, and gives the predetermined corrugated shape F1 to the steel plate 9, A pair of second rolls 2 that give the steel plate 9 a predetermined emboss shape F2 are provided.

  The pair of first rolls 1 is a metal that gives a corrugated shape F1 in which a plurality of preliminary recessed streak portions 32 are positioned at a distance in one direction 900 on the steel plate 9 by applying pressure to each part of the steel plate 9 and extending it. It has a mold structure 11.

  The pair of second rolls 2 has a mold structure 21 that gives an embossed shape F2 in which a plurality of concave strips 41 having a U-shaped cross section are positioned at a distance in one direction 900 on the steel plate 9 after preforming. .

  The preliminary groove portions 32 and the concave groove portions 41 correspond one-to-one, and the depth D1 of the preliminary groove portions 32 is the same as the depth D2 of the corresponding concave groove portions 41.

  Therefore, according to this manufacturing apparatus, the pre-forming step and the main step are sequentially performed on the flat steel plate 9, and the steel plate 9 is uniformly extended in the pre-forming step to form the corrugated shape F1. Since it is bent into the embossed shape F2 having the same depth, the steel plate 9 can be formed into an embossed shape F2 having a sharp appearance while suppressing the concentration of strain on a specific portion of the steel plate 9 during forming.

  In addition, the manufacturing apparatus of the second embodiment pre-forms the steel plate 9 and main-forms the pair of first rolls 1 that give the steel plate 9 a predetermined corrugated shape F1, and the pre-formed steel plate 9. A pair of second rolls 2 that give the steel plate 9 a predetermined emboss shape F2 are provided.

  The pair of first rolls 1 is a metal that gives a corrugated shape F1 in which a plurality of preliminary recessed streak portions 32 are positioned at a distance in one direction 900 on the steel plate 9 by applying pressure to each part of the steel plate 9 and extending it. It has a mold structure 11.

  The pair of second rolls 2 has a mold structure 21 that gives an embossed shape F2 in which a plurality of concave strips 41 having a U-shaped cross section are positioned at a distance in one direction 900 on the steel plate 9 after preforming. .

  The preliminary ridge portions 32 and the concave ridge portions 41 correspond one to one, and the depth D1 of the preliminary ridge portions 32 is larger than the depth D2 of the corresponding concave ridge portions 41.

  Therefore, according to this manufacturing apparatus, the pre-forming step and the main step are sequentially performed on the flat steel plate 9, and the steel plate 9 is uniformly extended in the pre-forming step to form the corrugated shape F1, and then Since it is bent into a shallow embossed shape F2, it is possible to form the steel plate 9 into a sharp embossed shape F2 while suppressing the concentration of strain on a specific part of the steel plate 9 during forming.

  As mentioned above, although the manufacturing method and manufacturing apparatus of the embossed steel plate were demonstrated, the manufacturing method and manufacturing apparatus of an embossed steel plate are not limited to above-described embodiment, What performed the appropriate design change and application of a well-known technique also. It is included in the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 1 1st roll 11 Mold structure 2 2nd roll 21 Mold structure 31 Preliminary convex part 41 Convex part 9 Steel plate 900 One direction D1 depth D2 depth F1 Corrugated shape F2 Embossed shape

Claims (5)

While passing a steel plate between a pair of first rolls and applying pressure to various portions of the steel plate and extending it, the steel plate has a predetermined corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction. Giving a preforming step;
By passing the steel plate provided with the corrugated shape between a pair of second rolls and bending the steel plate by applying pressure to each part of the steel plate, the steel plate has a plurality of concave portions having a U-shaped cross section. Providing a predetermined embossed shape positioned at a distance in the one direction,
The preliminary groove portion and the groove portion have a one-to-one correspondence, and the depth of the preliminary groove portion is the same as the depth of the corresponding concave portion,
A method for producing a steel sheet having an embossed shape. While passing a steel plate between a pair of first rolls and applying pressure to various portions of the steel plate and extending it, the steel plate has a predetermined corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction. Giving a preforming step;
By passing the steel plate provided with the corrugated shape between a pair of second rolls and bending the steel plate by applying pressure to each part of the steel plate, the steel plate has a plurality of concave portions having a U-shaped cross section. Providing a predetermined embossed shape positioned at a distance in the one direction,
The preliminary groove portion and the concave portion correspond to each other one by one, and the depth of the preliminary groove portion is larger than the depth of the corresponding concave portion,
A method for producing a steel sheet having an embossed shape. The depth of the concave portion is 2 mm to 4 mm,
A depth of the preliminary groove portion is larger by 0.5 mm to 1.5 mm than a corresponding depth of the groove portion, and is 5 mm or less,
The manufacturing method of the steel plate which has the emboss shape of Claim 2. A pair of first rolls that preform a steel plate and give the steel plate a predetermined corrugated shape,
A main roll of the steel plate after the preforming, and a pair of second rolls that give the steel plate a predetermined embossed shape,
The pair of first rolls includes:
By applying pressure to each part of the steel plate and extending the steel plate, the steel plate has a mold structure that gives the corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction,
The pair of second rolls is
The steel plate after the preforming has a mold structure that gives the embossed shape in which a plurality of concave portions having a U-shaped cross section are located at a distance in the one direction,
The preliminary groove portion and the groove portion have a one-to-one correspondence, and the depth of the preliminary groove portion is the same as the depth of the corresponding concave portion,
An apparatus for producing a steel plate having an embossed shape. A pair of first rolls that preform a steel plate and give the steel plate a predetermined corrugated shape,
A main roll of the steel plate after the preforming, and a pair of second rolls that give the steel plate a predetermined embossed shape,
The pair of first rolls includes:
By applying pressure to each part of the steel plate and extending the steel plate, the steel plate has a mold structure that gives the corrugated shape in which a plurality of preliminary concave portions are positioned at a distance in one direction,
The pair of second rolls is
The steel plate after the preforming has a mold structure that gives the embossed shape in which a plurality of concave portions having a U-shaped cross section are located at a distance in the one direction,
The preliminary groove portion and the concave portion correspond to each other one by one, and the depth of the preliminary groove portion is larger than the depth of the corresponding concave portion,
An apparatus for producing a steel plate having an embossed shape.