JPH08155576A - Production of deformed cross sectional band material and roll with projecting line - Google Patents

Abstract

PURPOSE: To obtain a deformed cross sectional band material having the same thick parts as the thickness and inclining angle at the difference of step parts with roll-forming by arranging the projecting parts to the suitable positions under consideration of metal flow at each part. CONSTITUTION: The metallic band material is passed through gap between a roll 30 with projections formed with plural projecting parts P31 -P33 and a flat roll 40 through plural grooving parts G1 -G4 in axial direction of the roll. The roll 30 with projections is provided with grooving parts G1 -G4 and the projecting parts P31 -P33 so that the ratio of the cross sectional area of the grooving parts G1 -G4 forming the thick parts S11 -S14 in the product to the integrating value of 1/2 of each cross sectional area of the projecting parts P31 -P33 at both sides becomes the constant in each thick parts S11 -S14 in the product. Further, the projecting parts P41 , P42 for trimming grooves are formed at the outside in the grooving roll axial direction forming the thick parts S11 -S14 in the product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously producing a strip material having a modified cross section having excellent shape accuracy by roll forming and a ridged roll.

[0002]

2. Description of the Related Art A strip material having a modified cross section in which a plurality of thick portions are formed in the width direction is used as a material for a lead frame, a bearing retainer and the like. This type of modified cross-section strip has been conventionally manufactured by a cutting method. In the cutting method, while passing a metal strip in the longitudinal direction, a thin portion in the plate width direction is continuously cut with a cutting tool, a milling cutter, or the like to form a thin portion that partitions the thick portions. However, the work efficiency is poor because cutting chips are generated which hinder the effective use of resources and the maintenance of a good working environment. In addition, burrs, warps, and the like are generated at the cut end portion, which causes deterioration of product quality.

As an alternative to the cutting method, Japanese Patent Publication Sho 53-
In Japanese Patent No. 27234, there is introduced a method for manufacturing a strip material having an irregular cross section by using a mold in which a ridge or a recess whose width gradually increases from the tip is formed. In this method, after feeding the metal strip to be rolled between the reciprocating flat roll and the die, the metal strip is pressed while reciprocating the flat roll, and the stepped portion that follows the cross-sectional shape of the die Is attached to the metal strip. Since this method is a batch method in which molding is performed intermittently, productivity is poor. Also, to prepare a large number of expensive dies corresponding to various target irregular cross-sectional shapes,
This causes an increase in manufacturing cost. Moreover, it is difficult to manufacture a plurality of strips having the same shape and different cross section at the same time, and it is difficult to put them on a mass production system. As a method for solving such a drawback, a method for producing a strip material having a modified cross section by roll forming is introduced in Japanese Patent Publication No. 1-59401 and Japanese Patent Application Laid-Open No. 1-299701.

In Japanese Examined Patent Publication No. 1-59401, a strip having a modified cross section is manufactured in the process shown in FIG. First, a metal strip S having a rectangular cross section is fed between the grooved roll 1a and the flat roll 1b, and the metal strip S of the portion S ₁ which becomes the product thin portion is rolled (FIG. 1a). At this time, in the portion which becomes the product thick portion, the metal strip S is buckled and deformed in the groove of the grooved roll 1a, and the curved portion S ₂ is formed. Then, the metal strip S with a pair of flat rolls 2a, passed during 2b, the upper and lower surfaces of the curved portion S ₂ is rolled to become parallel, to form a thick portion S ₃ (Fig. 1b). After that, the metal strip S is rolled into a product shape by using the finishing grooved roll 3a and the flat roll 3b (FIG. 1c). At this time, since the groove having a shape corresponding to the target irregular cross-sectional shape is formed in the circumferential direction of the finishing grooved roll 3a, the thick portion S ₃
Is formed along the roll profile of the finishing grooved roll 3a and becomes the thick portion S ₄ having the target shape.

In Japanese Patent Laid-Open No. 1-299701, FIG.
A strip material having a modified cross section is manufactured by the process shown in FIG. First, the metal strip S is rolled between the grooved roll 4a and the ridged roll 4b and rolled (FIG. 2a). The grooved roll 4a has a plurality of groove portions extending in the circumferential direction with a predetermined curvature in the axial direction. The ridged roll 4b has a plurality of ridges extending in the circumferential direction and having a predetermined curvature at positions corresponding to the grooves of the grooved roll 4a. After passing between the grooved roll 4a and the ridged roll 4b, a curved portion S ₂ having a predetermined curvature is formed on the metal strip S.
Next, the metal strip S is applied to the pair of flat rolls 5a, 5b.
And then rolled until the upper and lower surfaces of the curved portion S ₂ are parallel to each other to form a thick portion S ₃ (FIG. 2b). After that, the metal strip S is rolled into a product shape by using the finishing ridged roll 6a and the flat roll 6b (FIG. 1c).

[0006]

In the conventional roll forming method, in any of the methods shown in FIGS. 1 and 2, (1) only the thin portion is rolled to buckle the thick portion, or the thin portion is deformed. At least three steps of bending rolling, (2) rolling the buckled and deformed thick portion or curved rolled thin portion until the upper and lower surfaces are parallel, and (3) finishing rolling into a product shape Needed. The large number of steps necessitates preparing a large number of plural types of rolls to be used in each step, which becomes a bottleneck in improving productivity. Further, when a strip material having a different cross-section is manufactured by the conventional roll forming method, a stepped portion having a greatly different inclination angle is likely to be formed between the thick portion and the thin portion. Moreover, the respective thick portions do not match the recess depths of the grooved roll and the ridged roll, and the plate thicknesses are different from each other.

The low shape accuracy causes a decrease in reliability when the obtained profiled cross-section strip material is used as a product. For example, when slitting a profile strip to the product width and cutting out a single or multiple profile strips, the inclination angle of the step on both sides of the thin part and the plate thickness of the thick part are not the same. The reduction in the dimensional accuracy of the groove portion defined by the thin portion and the step portions on both sides of the thin portion directly reduces the product value. Specifically, in the bearing retainer manufactured from this modified cross-section strip, since the dimensional accuracy of the groove portion is different, smooth rolling of the bearing is hindered and the performance of the bearing itself is deteriorated. The present invention has been devised to solve such a problem, and by using a ridged roll having a profile designed so that the metal flow in each thick portion is uniform, It is an object of the present invention to obtain a deformed cross-section plate material having good shape accuracy in which the inclination angle of the step portion is constant without causing a lack of thickness in the meat portion.

[0008]

In order to achieve the object, a method for manufacturing a strip material having a modified cross section according to the present invention has a plurality of protrusions formed in the axial direction of the roll through a plurality of groove portions. When a strip material having a different cross-section is manufactured by roll forming with a strip roll and a flat roll, 1 of the cross-sectional area of the grooved portion forming the product thick portion and the cross-sectional area of each of the ridges on both sides of the grooved portion
Grooves and ridges are provided so that the ratio to the integrated value of / 2 is constant in each product thick part, and for the waste groove on the roll axial direction outer side of the groove forming the product thick part Using a ridged roll having a ridged portion, a metal strip at least equal to the distance between the waste groove ridges on both sides is passed between the ridged roll and the flat roll. Characterize. The ridged roll used in this method has a ratio of the cross-sectional area of the grooved portion forming the product thick portion to the integrated value of 1/2 of the cross-sectional area of each ridged portion on both sides of the grooved portion. So as to be constant in each product thick portion, a plurality of ridges are provided through a plurality of groove portions along the roll axial direction, and the roll axial direction of the groove portion forming the product thick portion A ridge portion for a waste groove is formed on the outside.

[0009]

The present inventors investigated the influence of the roll profile on the product shape when producing a strip having a modified cross section by roll forming. Then, it was found that the shape accuracy is improved when roll-forming a strip material having a plurality of irregular cross sections having a plurality of thick portions in the plate width direction. For example, as shown in FIG. 3, the ridged roll 10 provided with a plurality of ridges 11, 12, and 13 in the axial direction at intervals corresponding to the target thin portion is opposed to the flat roll 20. Roll 10,
The metal thick strip S that has passed between 20 has a thick central portion S ₁₁ ,
S ₁₂ and end thick portions S ₂₁ , S ₂₂ are formed, and each thick portion S
Thin portions S ₃₁ , S ₃₂ and S ₃₃ are formed between ₁₁ , S ₁₂ , S ₂₁ and S ₂₂ . However, the modified cross-section strip produced by this method is
The slope angle of the slope is different for each step. At the central step, the grooved roll 10 has an inclination angle θ ₃ ,
A step portion having the same inclination angle as θ ₄ is formed on the metal strip S, but at the step portions located at both ends, the inclination angles θ ₁ , θ ₂ , θ ₅ , θ ₆ of the grooved roll 10 Also tends to have large inclination angles θ ₁ ′, θ ₂ ′, θ ₅ ′, θ ₆ ′. Further, the end thick portions S ₂₁ and S ₂₂ are also thinner than the central thick portions S ₁₁ and S ₁₂ .

The increase in the inclination angle and the insufficient thickness of the thick end portions S ₂₁ and S ₂₂ result in a metal flow outward in the width direction caused by the open ends of the metal strip S. to cause. That is, in the groove between the ridges 11 and 12 and between the protrusions 12 and 13, the groove space is filled with the metal flow from the thin portions S ₃₁ , S ₃₂ , and S ₃₃ , and the central thick portion S ₁₁ , S.
₁₂ are formed along the roll profile. On the other hand, at the edge portion in the plate width direction, the influence of the metal flow flowing in one direction on the side surface is large, and the inclination angles θ ₁ ′ and θ ₆ ′ increase and the edge thick portion S increases.
_21, appears as a meat shortage of S _22. Further, in the portions where the metal flows on the left and right sides are different, the inclination angles θ ₂ 'and θ ₅ ' increase at the step portion where the material is less filled. Therefore, if the metal flow generated at both ends in the plate width direction can be regulated, the increase of the inclination angle and the lack of the thickness of the thick end portions S ₂₁ , S ₂₂ can be eliminated. Therefore, the present inventors further investigated and studied the influence of the roll profile on the shape accuracy of the modified cross-section strip material, and found that the metal flow generated during rolling was P ₃₁ , P ₃₂ , It was found that it depends on P ₃₃ and the cross-sectional area ratio of the voids. Also, theoretically, the effect of the cross-sectional area ratio on the metal flow is confirmed.

That is, when the cross-sectional area ratios are different, the portion having a large amount of metal flow fills the gap portion before the portion having a small amount of metal flow, so that rolling is selectively performed in the gap portion of the hole-type roll. On the other hand, the part with less metal flow is stretched in the rolling direction without being filled,
Further, the tendency of not being filled is promoted. As a result, the plate thickness of the unfilled portion does not match the groove of the holed roll. Due to such a phenomenon, the plate thickness and the inclination angle at each thick portion in the plate width direction of the product become uneven, and a predetermined product shape cannot be obtained. Specifically, it has been found that the ridged roll 30 having the profile shown in FIG. 4 is effective for improving the shape accuracy. The ridged roll 30 is
The ridges P ₃₁ , P ₃₂ , which form the thin portions S ₃₁ , S ₃₂ , S ₃₃ ,
A convex cross-sectional area of the P _33, adjoin in succession with protrusions _{P 31, P 32, P 33} , the thick-walled portion _{S 11, S 12, S 13} , groove portion G ₁ to form a S ₁₄ ~ The protrusions so that the ratio with the value obtained by integrating 1/2 of the recess cross-sectional area of each G ₄ is constant in any of the protrusions P ₃₁ , P ₃₂ , P ₃₃ and the groove portions G _{1 to} G ₄ . Article P
₃₁ , P ₃₂ , P ₃₃ and groove portions G _{1 to} G ₄ are designed. Outside the left and right thick-walled portions S ₁₁ and S ₁₄ , cut-out portions S ₅₁ and S _{52 in} which the thin-walled portions S ₄₁ and S ₄₂ are formed by the waste groove projections P ₄₁ and P ₄₂ are provided.

Considering the process of forming the thick portion S ₁₁ on the left side, the metal flow from the left and right thin portions S ₃₁ and S ₄₁ is added to the original thickness of the metal strip S corresponding to that portion. Further, the thick portion S _{12 at} the center is thickened by the metal flow from the left and right thin portions S ₃₁ , S ₃₂ . Therefore, as shown in FIG. 4B, half of the cross-sectional area of the protrusion P ₄₁ is A, half of the cross-sectional area of the groove portion G ₁ is B and C, and half of the cross-sectional area of the protrusion P _31. , D and E, F and G half of the cross-sectional area of the groove G ₂ , H and I half of the cross-sectional area of the ridge P ₃₂ , and J and K half of the cross-sectional area of the groove G ₃ . Ridge P ₃₃
When the half of the cross-sectional area of the groove portion is L and M, the half of the cross-sectional area of the groove portion G ₄ is N and O, and the half of the cross-sectional area of the ridge P ₄₂ is P, the formation of the thick portion S ₁₁ is affected. Cross-sectional area ratio (A + D) / (B + C) in the region to be formed, cross-sectional area ratio (E + H) / (F + G) in the region that affects the formation of thick portion S ₁₂ , thick portion S
Cross-sectional area ratio (I + L) / in the area that affects the formation of ₁₃
(J + K) and the cross-sectional area ratio (M + P) / (N + O) in the region that affects the formation of the thick portion S ₁₄ are set to the same value. In this way, when the flat roll 40 is made to face the roll with ridges 30 in which the ridge portion and the groove portion are designed, and the metal strip S is formed, the thick portion S ₃₁ , in the formed deformed cross-section strip, The plate thicknesses of S ₃₂ and S ₃₃ correspond to the heights H _{1 to} H ₄ from the peripheral surface of the flat roll 40 to the respective groove portions G _{1 to} G ₄ and have the same thickness. In addition, the inclination angle of the step portion θ ₁ ~
θ ₆ is the side surface F ₃₁ , F ₃₂ , F of the protrusions P ₃₁ , P ₃₂ , P _33.
It corresponds to the inclination angles θ _{1 to} θ ₆ of ₃₃ . As a result, a modified cross-section strip having a cross-sectional shape with high dimensional accuracy is manufactured.

In FIG. 4 (a), thin-walled portions S ₃₁ , S are provided at the center.
_It shows a case where three strips of irregular cross-section having ₃₂ and S ₃₃ are manufactured, and the metal strip after roll forming is slit into each strip. However, the present invention is not limited to this, a method for simultaneously molding a plurality of strips,
As shown in FIG. 5 (a), it is also applied to the case where a plurality of modified cross-section strip materials having two thin-walled portions are simultaneously manufactured. In this case, a cut-off portion S ₅₃ is provided between each of the modified cross-section strip materials to be a product, and a thin-walled portion S ₄₃ for regulating the metal flow is cut-off portion S _53.
To form. Corresponding to this, the ridged roll 40,
As shown in FIG. 5B, a waste groove protrusion P ₄₃ is formed in the center. As the material of the modified cross-section strip material, a simple material made of Cu, Cu alloy, Al, Al alloy, steel, Fe alloy, or the like, or a composite material combining these can be used. The width of the deformed metal strip including the cut-off portions S ₅₁ and S ₅₂ , or a strip having a width larger than that, is passed between the ridge roll 30 and the flat roll 40, and then, as shown in FIGS. It is molded into the modified cross section shown in. Then, the cut-off portions S ₅₁ , S ₅₂ , and S ₅₃ are separated to obtain a product strip.

[0014]

EXAMPLE In this example, as shown in FIG.
A ridged roll 30 having a thin-walled portion-forming ridge P ₃₁ , P ₃₂ , P ₃₃ and two waste groove-forming ridges P ₄₁ , P ₄₂ formed in a body portion having a diameter of 400 mm was used. . Ridge P ₃₁ ,
P ₃₂ and P ₃₃ have a height of 1.75 mm, a length of the top surface in the roll axial direction of 11.5 mm, and inclination angles θ of the slopes F ₃₁ , F ₃₂ , and F _33.
The trapezoidal cross section was symmetrical with _{1 to} θ ₆ of 30 degrees. The groove portions G _{1 to} G ₄ all have a length in the roll axial direction of 13.88.
It was set to mm. The lengths of the protrusions P ₄₁ and P ₄₂ for forming the waste groove in the roll axial direction of the top surface are set to 6 mm. At this time,
Area cross-sectional area ratio (A + D) / (B + C), area cross-sectional area ratio (E + H) / (F + G), area cross-sectional area ratio (I
+ L) / (J + K), cross-sectional area ratio (M + P) /
(N + O) has the same value of 0.83. For comparison, a projection for forming a waste groove having a top surface with a roll axis length of 6 mm at a position where the cross-sectional area ratios (A + D) / (B + C) and (M + P) / (N + O) of the area are 0.65. Article P
₄₁ , P ₄₂ formed ridged roll (Comparative Example 1), area and sectional area ratio (A + D) / (B + C) and (M +
Roll with ridges, in which protrusion grooves P ₄₁ , P ₄₂ for forming a waste groove having a roll axial length of 6 mm on the top surface are formed at a position where P) / (N + O) is 1.2 (Comparative Example 2) It was used.

Each of the ridged rolls was opposed to a flat roll, and a plain steel strip having a plate thickness of 2.3 mm and a plate width of 110 mm was passed as a strip to be rolled to produce a strip having a modified cross section. FIG. 6 shows the result of measuring the shape of each part of the obtained strip material having a modified cross section. As shown in FIG. 6 (a), the strip material having a modified cross section manufactured by using the roll with ridges according to the present invention corresponds to the inclination angles of the slopes F ₃₁ , F ₃₂ , F ₃₃ of the step portion, and The tilt angle was also a substantially constant value of 35 degrees. On the other hand, Comparative Example 1 in which the protrusion groove portions P ₄₁ and P ₄₂ for the waste groove are brought close to the central portion of the roll
Then, the inclination angle of the central step portion becomes large, and the inclined surface F ₃₂
Is larger than the angles θ ₃ and θ ₄ . On the other hand, in Comparative Example 2 in which the salient groove projections P ₄₁ and P ₄₂ are spread from the center of the roll to both sides, the inclination angles of the stepped portions on both sides are large, and the angles θ _{1 of} the inclined surfaces F ₃₁ and F ₃₃ are It became larger than θ ₆ .
From this, it can be understood that the influence of the metal flow flowing in the left-right direction is significantly manifested when the waste groove projections P ₄₁ and P ₄₂ are not at the proper positions.

Forming the projection groove portions P ₄₁ , P ₄₂ for the waste groove at appropriate positions is performed by forming the thick wall portions S ₃₁ , S ₃₂ , S ₃₃ in FIG. 6B.
It is also effective in achieving a uniform wall thickness as shown in. That is, when using the ridged roll according to the present invention,
The thick portions S ₃₁ , S ₃₂ , and S ₃₃ have a height H ₁ from the flat roll 40 to the groove portions G _{1 to} G ₄ of the ridged roll 30.
It was 2.5 mm, which is almost equal to H ₄ . Incidentally, outside the thin-walled portions S ₄₁ , S ₄₂ , the thicknesses t ₁ , t ₂ were reduced to 2.4 mm due to the influence of the lateral metal flow. However, since the irregular cross-section strip material is obtained by removing the cut-off portions S ₅₁ and S ₅₂ , the shortage of the thicknesses t ₁ and t ₂ has no influence on the product quality. On the other hand, in Comparative Example 1 in which the protrusion groove portions P ₄₁ and P ₄₂ for the waste groove are brought close to the central portion of the roll,
The influence of the metal flow flowing outward in the plate width direction was not completely removed, and the thick portions S ₁₁ and S ₁₄ on both sides were insufficient in thickness. On the other hand, in Comparative Example 2 in which the salient groove projections P ₄₁ and P ₄₂ are spread from the central portion of the roll to both sides, on the contrary, the central thick portions S ₁₂ and S ₁₃ are insufficient in thickness. The meat shortage, a large amount of metal flow occurs toward the thin portion S _31, S ₃₃ to the thick portion S _11, S _14, thin part S ₃₁ by that amount, S
It is considered that the metal flow from ₃₃ to the thick portions S ₁₂ and S ₁₃ decreased.

[0017]

As described above, in the present invention, the ridged roll having the ridges for the waste groove formed at the proper positions on both sides of the ridge for forming the thin portion is opposed to the flat roll. By passing the strip to be rolled, the influence of the metal flow outward in the plate width direction is eliminated, and the metal flow from each thin portion to the thick portion is adjusted. As a result, a sufficient amount of meat is supplied to the groove-shaped space of the ridged roll, the profile of the ridged roll is accurately transferred, and a deformed cross-section strip material having good shape accuracy is manufactured. According to this method, it is not necessary to prepare various rolls for manufacturing one kind of modified cross-section strip material, and a modified cross-section strip material suitable as a lead frame, a bearing retainer or the like can be obtained with high productivity. In addition, since a strip material having a different cross-section having a different shape can be manufactured simply by exchanging the ridged rolls, it is possible to perform the production according to various needs.

[Brief description of drawings]

FIG. 1 is a step of manufacturing a strip material having a modified cross section according to a conventional method.

FIG. 2 is a step of manufacturing a strip material having a modified cross section according to another conventional method.

[Fig. 3] State in which a strip having a modified cross section is manufactured using a roll with ridges

FIG. 4 shows a state in which a strip with a ridge according to the present invention is made to face a flat roll to produce a strip with a modified cross section, a cross-sectional area ratio of each part (b), and the appearance of the roll with a ridge ( c)

FIG. 5 shows a state in which two strips of irregular cross-section having two thin portions are simultaneously formed (a) and the appearance of a ridged roll to be used (b).

FIG. 6 is a graph comparing the inclination angle (a) of the step portion and the plate thickness (b) of the thick portion of the strip material with a modified cross section manufactured in the example of the present invention, in comparison with the comparative example.

[Explanation of symbols]

S: metal strip S ₁₁ ~S _14: product thick-walled portion S ₃₁ ~S
₃₃ : Thin part S ₄₁ , S ₄₂ : Thin part for cutting S ₅₁ ,
S ₅₂ : Cut-off portions t ₁ , t ₂ : Plate thickness of cut-off portion 30: Roll with protrusions according to the present invention P _{31 to} P ₃₃ :
Ridges P ₄₁ , P ₄₂ : Ridges for ridges G _{1 to} G
₄ : Grooves F _{31 to} F ₃₃ , F ₄₁ , F ₄₂ : Slope of stepped portion θ _{1 to} θ ₆ : Inclination angle of slope H _{1 to} H ₄ : Height from flat roll to grooved portion (≒ product Thickness of thick part) 40: Flat roll

Claims (2)

[Claims] 1. A thick part of a product when a deformed cross-section strip is manufactured by roll molding with a roll with a ridge having a plurality of ridges formed in the axial direction of the roll through a plurality of grooves and a flat roll. The groove-shaped portion is formed so that the ratio of the cross-sectional area of the groove-shaped portion that forms the groove and the integrated value of 1/2 of the cross-sectional area of each of the ridges on both sides of the groove-shaped portion is constant in each product thick portion. And a protrusion-provided roll in which a protrusion groove portion for forming a waste groove is formed on the outer side in the roll axial direction of a groove portion forming a product thick portion, and the protrusion grooves for waste groove on both sides are used. A method of manufacturing a strip material having a different cross-section, comprising: passing a metal strip material having a distance equal to or more than a distance between the ridged roll and the flat roll. 2. A roll which is arranged opposite to a flat roll and which forms a strip material having an irregular cross section having a plurality of thick portions,
The ratio of the cross-sectional area of the groove-like portion forming the product thick-walled portion to the integrated value of 1/2 of the cross-sectional area of each of the ridges on both sides of the groove-like portion is constant in each product thick-walled portion. A plurality of ridges are provided along the roll axial direction via a plurality of groove-shaped portions, and a waste groove ridge is formed outside the groove-shaped portion forming the product thick portion in the roll axial direction. Roll with ridges.