ASYMMETRICAL ROLLING DEVICE

Abstract

The present disclosure relates to an asymmetric rolling device capable of enhancing a physical property of materials and may include: a first work roll contacting a first surface of a material to be rolled; a second work roll contacting a second surface of the material to be rolled and having a second radius greater than a first radius of the first work roll so as to asymmetrically roll the material to be rolled; a drive roll contacting the first work roll and formed above or below the first work roll so as to drive the first work roll; a driving device driving the second work roll or the drive roll; and a first idle roll contacting the first work roll and formed at a front or a back of the first work roll to support the first work roll in a longitudinal direction of the material.

Claims

1. An asymmetric rolling device comprising: a first work roll contacting a first surface of a material to be rolled; a second work roll contacting a second surface of the material to be rolled and having a second radius greater than a first radius of the first work roll so as to asymmetrically roll the material to be rolled; a drive roll contacting the first work roll and formed above or below the first work roll so as to drive the first work roll; a driving device driving the second work roll or the drive roll; and a first idle roll contacting the first work roll so as not to interfere with a linear movement path of the material to be rolled and formed at a front or a back of the first work roll to support the first work roll in a longitudinal direction of the material.

2. The asymmetric rolling device of claim 1, wherein the first idle roll is formed to be spaced apart from the drive roll by a first gap and has a third radius smaller than the first radius of the first work roll so as not to interfere with a rolling path of the material to be rolled.

3. The asymmetric rolling device of claim 2, wherein the first idle roll includes: a 1-1 idle roll formed at the front of the first work roll, and of which a second height of a second central axis is formed to be the same as a first height of a first central axis of the first work roll; and a 1-2 idle roll formed at the back of the first work roll, and of which a third height of a third central axis is formed to be the same as the first height of the first central axis of the first work roll.

4. The asymmetric rolling device of claim 1, wherein the driving device drives each of the drive roll and the second work roll so that a first rotational linear velocity of the first work roll is the same as a second rotational linear velocity of the second work roll.

5. The asymmetric rolling device of claim 4, wherein the driving device drives the drive roll and the second work roll at the same rotational angular velocity, and a fourth radius of the drive roll and the second radius of the second work roll are the same to each other so that the first rotational linear velocity of the first work roll is the same as the second rotational linear velocity of the second work roll.

6. The asymmetric rolling device of claim 1, further including a first guide roll contacting the first idle roll and formed at a front or a back of the first idle roll so as to support the first idle roll in a longitudinal direction of the material or in a circumferential direction of the drive roll.

7. The asymmetric rolling device of claim 6, wherein the first guide roll contacts the drive roll and has a fifth radius greater than the first radius of the first work roll or greater than a third radius of the first idle roll so as not to interfere with a rolling path of the material to be rolled.

8. The asymmetric rolling device of claim 7, wherein the first guide roll includes: a 1-1 guide roll formed at the front of the first work roll, and of which a fourth height of a fourth central axis is formed to be greater than a first height of a first central axis of the first work roll; and a 1-2 guide roll formed at the back of the first work roll, and of which a fifth height of a fifth central axis is formed to be greater than the first height of the first central axis of the first work roll.

9. The asymmetric rolling device of claim 6, wherein the first guide roll is formed to be spaced apart from the drive roll by a second gap.

10. The asymmetric rolling device of claim 6, further including a second idle roll contacting the first guide roll and formed at a front or a back of the first guide roll so as to support the first guide roll in the longitudinal direction of the material or the circumferential direction of the drive roll.

11. The asymmetric rolling device of claim 10, further including a second guide roll contacting the second idle roll and formed at a front or a back of the second idle roll so as to support the second idle roll in the longitudinal direction of the material or the circumferential direction of the drive roll.

12. The asymmetric rolling device of claim 1, wherein the first work roll includes: a rolling portion contacting the material to be rolled so as to roll the material to be rolled; a joint portion formed in the rolling portion so that the rolling portion is joint-moved articulated in the longitudinal direction of the material; and a sliding portion formed in the rolling portion so that the rolling portion slides in an axial direction while rotating.

13. The asymmetric rolling device of claim 12, wherein the joint portion is formed by selecting at least one of a joint ball, an angular contact bearing, and combinations thereof, which is installed in a shaft hole portion concavely formed at an end portion of the rolling portion.

14. The asymmetric rolling device of claim 13, wherein the sliding portion includes: a sleeve loosely inserted into the shaft hole portion of the rolling portion; a sleeve rotation shaft installed on the sleeve so as to rotate freely; a guide bush fixed to a cassette body or formed so as to rotate freely and supporting the sleeve rotation shaft so as to be rotatable and slidable; and a damping device installed on the sleeve rotation shaft and returning a sliding position of the sleeve rotation shaft when no load is applied while alleviating vibration and noise.

15. The asymmetric rolling device of claim 14, wherein the damping device includes: a compression spring installed at one side of the sleeve rotation shaft and an elastic restoring force acts thereon during compression; and an extension spring installed at the other side of the sleeve rotation shaft and an elastic restoring force acts thereon during expansion.

16. The asymmetric rolling device of claim 14, wherein the sliding portion further includes: at least one deep groove ball bearing formed between the sleeve and the sleeve rotation shaft; and a thrust bearing formed between the guide bush and a bush cap.

17. The asymmetric rolling device of claim 6, wherein the first guide roll includes: a contact portion in which at least one rolling oil injecting groove portion is formed and contacting the first idle roll; a shaft portion in which one end portion is fixed to a cassette body and the other end portion is inserted into a concave portion concavely formed at an end portion of the contact portion; and at least one self-aligning bearing formed between the contact portion and the shaft portion so that a rotation center of the contact portion is aligned and rotated.

18. The asymmetric rolling device of claim 17, wherein the rolling oil injecting groove portion includes a circumferential linear groove portion formed in a ring-type linear groove shape along a circumference of the contact portion so that an injected rolling oil passes through the rolling oil injecting groove portion, passes a first gap between the first idle roll and the drive roll, and is directly injected into the first work roll.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a perspective view showing an asymmetric rolling device according to some embodiments of the present disclosure.

[0028] FIG. 2 is a cross-sectional view showing the asymmetric rolling device of FIG. 1.

[0029] FIG. 3 is an enlarged cross-sectional view showing the asymmetric rolling device of FIG. 2.

[0030] FIG. 4 is a cross-sectional view showing an asymmetric rolling device according to some other embodiments of the present disclosure.

[0031] FIG. 5 is a cross-sectional view showing an asymmetric rolling device according to some embodiments or still other embodiments of the present disclosure.

[0032] FIG. 6 is a cross-sectional view showing a first work roll of the asymmetric rolling device of FIG. 1.

[0033] FIG. 7 is an enlarged cross-sectional view showing a part of the first work roll of the asymmetric rolling device of FIG. 6.

[0034] FIG. 8 is a cross-sectional view showing a first idle roll of the asymmetric rolling device of FIG. 1.

[0035] FIG. 9 is a cross-sectional view showing a first guide roll of the asymmetric rolling device of FIG. 1.

[0036] FIG. 10 is a cross-sectional view showing a state in which rolling oil is directly injected into a first work roll through a rolling oil injecting groove portion of the asymmetric rolling device of FIG. 9.

[0037] FIG. 11 is a cross-sectional view showing another example of the rolling oil injecting groove portion of the asymmetric rolling device of FIG. 1.

MODE FOR INVENTION

[0038] Hereinafter, various preferred embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0039] Various embodiments of the present disclosure may be embodied in many different forms and should not be construed as being limited to the example embodiments set forth herein. Rather, these example embodiments of the disclosure are provided so that this disclosure will be thorough and complete and will convey inventive concepts of the disclosure to those skilled in the art. Also, in the drawings, the thicknesses or sizes of layers are exaggerated for clarity.

[0040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise. It will be further understood that the terms comprises and/or comprising used herein specify the presence of stated shapes, numbers, steps, operations, members, elements, and/or groups thereof, but do not preclude the presence or addition of one or more other shapes, numbers, steps, operations, members, elements, and/or groups thereof.

[0041] Embodiments of the disclosure are described herein with reference to schematic illustrations of idealized embodiments (and intermediate structures) of the disclosure. In the drawings, for example, according to the manufacturing technology and/or tolerance, variations from the illustrated shape may be expected. Thus, the embodiments of the disclosure should not be construed as limited to the particular shapes of regions illustrated herein, but are to include deviations in shapes that result, for example, from manufacturing.

[0042] FIG. 1 is a perspective view showing an asymmetric rolling device 100 according to some embodiments of the present disclosure, FIG. 2 is a cross-sectional view showing the asymmetric rolling device 100 of FIG. 1, and FIG. 3 is an enlarged cross-sectional view showing the asymmetric rolling device 100 of FIG. 2.

[0043] First, as shown in FIGS. 1 to 3, the asymmetric rolling device 100 according to some embodiments of the present disclosure may broadly include a first work roll WR1, a second work roll WR2, a drive roll DR, a driving device 70, a first idle roll IR1, and a first guide roll GR1.

[0044] For example, the first work roll WR1 may be a rolling roll contacting a first surface 1a, that is, an upper surface of a material to be rolled 1 having a panel shape.

[0045] The second work roll WR2 corresponding to this may be a rolling roll contacting a second surface 1b, that is, a lower surface of the material to be rolled 1, and may have a second radius R2 greater than a first radius R1 of the first work roll WR1 so as to asymmetrically roll the material to be rolled 1.

[0046] In the drawing, the first work roll WR1 is positioned above the material to be rolled 1, and the second work roll WR2 is positioned below the material to be rolled 1, but it is not necessarily limited thereto, and the first work roll WR1 may be positioned below the material to be rolled 1, and the second work roll WR2 may be positioned above the material to be rolled 1. Alternatively, the first work roll WR1 may be positioned at one side of the material to be rolled 1, and the second work roll WR2 may be positioned at the other side of the material to be rolled 1.

[0047] Therefore, the material to be rolled 1 may be rolled thinly from a first thickness T to a second thickness t by passing through between the first work roll WR1 and the second work roll WR2, and at this time, since radii of two rolling rolls for rolling the material to be rolled 1 are different from each other, a shear deformation force acting on the material to be rolled 1 may act differently from each other to make a structure of the material more dense, and accordingly, the physical property of materials may be more enhanced.

[0048] Such enhancement of the physical property of materials may vary depending on a type, thickness, specification, process environment such as process temperature, etc. of the material to be rolled 1, and thus a diameter or the like of the first work roll WR1 and the second work roll WR2 may be optimized and designed according to the type, thickness, specification, process environment such as process temperature, etc. of the material to be rolled 1.

[0049] Meanwhile, for example, the drive roll DR may be a kind of an auxiliary roll contacting the first work roll WR1 and formed above or below the first work roll WR1 so as to drive the first work roll WR1 and may be driven by the driving device 70.

[0050] In addition, for example, the driving device 70 may be a device driving the second work roll WR2 and the drive roll DR, and may drive each of the drive roll DR and the second work roll WR2 so that a first rotational linear velocity V1 of the first work roll WR1 is the same as a second rotational linear velocity V2 of the second work roll WR2.

[0051] More specifically, for example, the driving device 70 may include a first actuator 71 including a motor for driving the first work roll WR1 or a power transmission device, a second actuator 72 including a motor for driving the second work roll WR2 or a power transmission device, and a drive control unit 73 for controlling the first actuator 71 and the second actuator 72.

[0052] Therefore, the first actuator 71 and the second actuator 72 may control a rotational angular velocity of each of the first work roll WR1 and the second work roll WR2 so that the first rotational linear velocity V1 of the first work roll WR1 is the same as the second rotational linear velocity V2 of the second work roll WR2.

[0053] Alternatively, the driving device 70 may drive the drive roll DR and the second work roll WR2 at the same rotational angular velocity in the same or opposite direction, and a fourth radius R4 of the drive roll DR and the second radius R2 of the second work roll WR2 may be the same to each other so that the first rotational linear velocity V1 of the first work roll WR1 is the same as the second rotational linear velocity V2 of the second work roll WR2.

[0054] The definition of same herein should be understood as a practical meaning of identity that includes not only complete identity but also identity within a process margin caused by inevitable errors implied due to the nature of a mechanical apparatus, even though an operator controlled a signal of a control unit with an intention of making the angular velocity of both rolls the same. The term same with respect to the rotational linear velocity of the first work roll WR1 and the second work roll WR2 may be applied in the same meaning hereinafter.

[0055] However, in other embodiments of the present disclosure, the first rotational linear velocity V1 of the first work roll WR1 and the second rotational linear velocity V2 of the second work roll WR2 may not be the same for various intentions. For example, the first rotational linear velocity V1 and second rotational linear velocity V2 may be controlled to have a slight difference, for example, a difference within a range of 10%, in order to make a difference in shear deformation above and below the material to be rolled 1 or to control the warpage of the material to be rolled 1.

[0056] In addition, although not shown, various power transmission devices such as a gear combination, a belt pulley combination, a chain sprocket wheel combination, a wire pulley combination, a movable base and a screw rod combination, in addition to a motor may be applied to the first actuator 71 and the second actuator 72.

[0057] In addition, for example, the first idle roll IR1 may be a kind of an auxiliary rolling roll contacting the first work roll WR1 so as not to interfere with a linear movement path of the material to be rolled 1 and formed at a front or a back the first work roll WR1 to support the first work roll WR1 in the longitudinal direction of the material.

[0058] Here, the first idle roll IR1 may be a rolling roll formed to be spaced apart from the drive roll DR by a first gap D1 and having a third radius R3 smaller than the first radius R1 of the first work roll WR1 so as not to interfere with the rolling path of the material to be rolled 1.

[0059] More specifically, for example, the first idle roll IR1 may include a 1-1 idle roll IR1-1 formed at the front of the first work roll WR1, and of which a second height H2 of a second central axis C2 is formed to be the same as a first height H1 of a first central axis C1 of the first work roll WR1, and a 1-2 idle roll IR1-2 formed at the back of the first work roll WR1, and of which a third height H3 of a third central axis C3 is formed to be the same as the first height H1 of the first central axis C1 of the first work roll WR1.

[0060] Therefore, the 1-1 idle roll IR1-1 and the 1-2 idle roll IR1-2 may support the first work roll WR1 to rotate more firmly not only in the longitudinal direction, that is, at the front of the first work roll WR1, but also in the longitudinal direction, that is, at the back of the first work roll WR1.

[0061] In addition, for example, the first guide roll GR1 may be a kind of auxiliary rolling roll contacting the first idle roll IR1 and formed at a front or a back of the first idle roll IR1 so as to support the first idle roll IR1 in the longitudinal direction of the material or in a circumferential direction of the drive roll DR.

[0062] The first guide roll GR1 may be a rolling roll contacting the drive roll DR for a more firm rotation supporting force and having a fifth radius R5 greater than the first radius R1 of the first work roll WR1 or greater than the third radius R3 of the first idle roll IR1 so as not to interfere with the rolling path of the material to be rolled 1.

[0063] More specifically, for example, the first guide roll GR1 may include a 1-1 guide roll GR1-1 formed at the front of the first work roll WR1, and of which a fourth height H4 of a fourth central axis C4 is formed to be greater than the first height H1 of the first central axis C1 of the first work roll WR1, and a 1-2 guide roll GR1-2 formed at the back of the first work roll WR1, and of which a fifth height H5 of a fifth central axis C5 is formed to be greater than the first height H1 of the first central axis C1 of the first work roll WR1.

[0064] Therefore, the 1-1 guide roll GR1-1 and the 1-2 guide roll GR1-2 may support the first work roll WR1 and the first idle roll IR1 to rotate more firmly not only in the longitudinal direction, that is, at the front of the first work roll WR1, but also in the longitudinal direction, that is, at the back of the first work roll WR1.

[0065] Thus, according to the present disclosure, since the first work roll WR1 may be supported in a triangular arrangement to be in contact with each other by using the first idle rolls IR1 and the first guide rolls GR1 capable of supporting the first work roll WR1 in the longitudinal direction, it is possible to firmly respond to a reaction force of the longitudinal direction, and to minimize the deformation of the longitudinal direction of the first work roll WR1, and thereby increasing the strength and durability of components and precisely controlling a shape of a plate material produced by preventing a defective phenomenon.

[0066] FIG. 4 is a cross-sectional view showing an asymmetric rolling device 200 according to some other embodiments of the present disclosure.

[0067] As shown in FIG. 4, a first guide roll GR1 of the asymmetric rolling device 200 according to some other embodiments of the present disclosure may be formed to be spaced apart from the drive roll DR by a second gap D2.

[0068] Therefore, it is also possible to induce cooling and smooth operation of the rolling rolls by passing through a rolling oil between the second gap D2 using the first guide roll GR1 that is spaced apart from the drive roll DR.

[0069] FIG. 5 is a cross-sectional view showing an asymmetric rolling device 300 according to some embodiments or still other embodiments of the present disclosure.

[0070] As shown in FIG. 5, the asymmetric rolling device 300 according to some embodiments or still other embodiments of the present disclosure may further include a second idle roll IR2 contacting the first guide roll GR1 and formed at a front or a back of a first guide roll GR1 so as to support the first guide roll GR1 in a longitudinal direction of the material or in a circumferential direction of the drive roll DR, and a second guide roll GR2 contacting the second idle roll IR2 and formed at a front or a back of a second idle roll IR2 so as to support the second idle roll IR2 in the longitudinal direction of the material or in the circumferential direction of the drive roll DR.

[0071] More specifically, for example, the second idle roll IR2 may include a 2-1 idle roll IR2-1 formed at a front of the first guide roll GR1 and a 2-2 idle roll IR2-2 formed at a back of the first guide roll GR1.

[0072] In addition, the second guide roll GR2 may include a 2-1 guide roll GR2-1 formed at a front of the second idle roll IR2 and a 2-2 guide roll GR2-2 formed at a back of the second idle roll IR2.

[0073] Therefore, since the first work roll WR1 may be supported in a multi-triangular arrangement to be in contact with each other by using the first idle roll IR1, the first guide rolls GR1, the second idle roll IR2, and the second guide rolls GR2 capable of supporting the first work roll WR1 the longitudinal direction, it is possible to firmly respond to a reaction force of the longitudinal direction, and to minimize the deformation of the longitudinal direction of the first work roll WR1, and thereby increasing the strength and durability of components and precisely controlling a shape of a plate material produced by preventing a defective phenomenon.

[0074] FIG. 6 is a cross-sectional view showing a first work roll WR1 of the asymmetric rolling device 100 of FIG. 1, and FIG. 7 is an enlarged cross-sectional view showing a part of the first work roll WR1 of the asymmetric rolling device 100 of FIG. 6.

[0075] As shown in FIGS. 1 to 7, the first work roll WR1 of the asymmetric rolling device 100, 200, and 300 according to various embodiments of the present disclosure may include a rolling portion 10 contacting a material to be rolled 1 so as to roll the material to be rolled 1, a joint portion 20 formed in the rolling portion 10 so that the rolling portion 10 may be joint-moved in the longitudinal direction of the material, and a sliding portion 30 formed in the rolling portion 10 so that the rolling portion 10 slides in an axial direction while rotating.

[0076] For example, the rolling portion 10 of the first work roll WR1 may be a portion formed in an overall cylindrical shape that contacts the first surface 1a of the material to be rolled 1.

[0077] In addition, for example, as shown in FIG. 6, the joint portion 20 of the first work roll WR1 is formed between the rolling portion 10 and the sliding portion 30, and as shown in FIG. 7, the joint portion 20 may be formed by selecting at least one of a joint ball 21, an angular contact bearing 22, and combinations thereof, which is installed in a shaft hole portion 10a concavely formed at an end portion of the rolling portion 10 to enable joint movement of the rolling portion 10.

[0078] Here, as shown in an enlarged right portion of FIG. 7, a steel ball bearing inserted into the shaft hole portion 10 may be applied to the joint ball 21, and an angular contact ball bearing or an angular contact roller bearing consisting of an inner ring 221 having one side protruded and an outer ring 222 having the other end protruded so as to withstand a thrust load and balls 223 or rollers installed therebetween may be applied to the angular contact bearing 22.

[0079] However, the joint ball 21 and the angular contact bearing 22 are not necessarily limited to the drawing, and a wide variety of forms of bearings that may rotate while withstanding both the rolling load and the thrust load may be applied.

[0080] In addition, for example, as shown in FIG. 7, the sliding portion 30 of the first work roll WR1 may include a sleeve 31 loosely inserted into the shaft hole portion 10a of the rolling portion 10, a sleeve rotation shaft 32 installed on the sleeve 31 so as to rotate freely, a guide bush 33 fixed to a cassette body 81 or formed so as to rotate freely and supporting the sleeve rotation shaft 32 so as to be rotatable and slidable, and a damping device 34 installed on the sleeve rotation shaft 32 and returning a sliding position of the sleeve rotation shaft 32 when no load is applied while alleviating vibration and noise.

[0081] More specifically, for example, the damping device 34 may include a compression spring 35 installed at one side of the sleeve rotation shaft 32 and an elastic restoring force acts thereon during compression, and an extension spring 36 installed at the other side of the sleeve rotation shaft 32 and an elastic restoring force acts thereon during expansion.

[0082] Therefore, the sleeve 31 may be installed independently from the rolling portion 10 so as to rotate freely, and the sleeve rotation shaft 32 may rotate and slide based on a guide bush 33 so as to be slidable and rotatable in the axial direction together with joint movement of the joint portion 20 described above, and the damping device 34 may be used to returning the sliding position of the sleeve rotation shaft 32 when no load is applied.

[0083] Here, the sleeve 31, the sleeve rotation shaft 32, the guide bush 33 and the damping device 34 may be installed on left and right end portions of the rolling portion 10, respectively, so that when the rolling portion 10 slides to the left, a restoring force acts in the right direction, and when the rolling portion 10 slides to the right, a restoring force acts in the left direction, thereby restoring the sliding position.

[0084] Therefore, the damping device 34 may respond to the thrust load by acting as a damper that repeats compression and expansion, and may prevent damage to the bearing by reducing a bearing load concentrated on the bearing.

[0085] In addition, as shown in FIG. 7, the sliding portion 30 of the first work roll WR1 may further include at least one deep groove ball bearing 37 formed between the sleeve 31 and the sleeve rotation shaft 32, and a thrust bearing 38 formed between the guide bush 33 and a bush cap BC.

[0086] More specifically, for example, as shown in an enlarged central portion of FIG. 7, the deep groove ball bearing 37 is a bearing consisting of an inner ring 371 in which a groove is formed, an outer ring 372 in which a groove is formed, and balls 373 inserted between the grooves, and may minimize a friction force generated between the sleeve 31 and sleeve rotation shaft 32 when a rolling load is generated.

[0087] In addition, for example, as shown in an enlarged left portion of FIG. 7, the thrust bearing 38 is a bearing consisting of a fixed ring 381 installed on the bush cap BC, a rotating ring 382 installed on the guide bush 33 side, and a ball 383 installed therebetween, and in a case where the guide bush 33 is rotated when a rotation load is generated, a friction force generated between the fixed bush cap BC and the guide bush 33 may be minimized.

[0088] However, the deep groove ball bearing 37 and the thrust bearing 38 are not necessarily limited to the drawings, and a wide variety of forms of bearings that may rotate while withstanding both the rolling load and the thrust load may be applied.

[0089] Therefore, by using the joint portion 20 and the sliding portion 30 of various forms suitably disposed for each portion, the joint movement, rotational movement, and sliding in axial direction of the rolling portion 10 may be made possible, and accordingly, it is possible to be aligned and returned to the original position in an active response even when a large deformation occurs in the first work roll WR1 due to a strong rolling load, and thereby increasing the strength and durability of the components and precisely controlling the shape of the plate material produced by preventing a defective phenomenon.

[0090] FIG. 8 is a cross-sectional view showing a first idle roll IR1 of the asymmetric rolling device 100 of FIG. 1.

[0091] As shown in FIG. 8, the first idle roll IR1 of the asymmetric rolling device 100, 200, and 300 according to various embodiments of the present disclosure may include an idle portion IRa contacting the first work roll WR1, a tapered portion IRb having a radius that is gradually reduced from the idle portion IRa to alleviate a corner stress concentration phenomenon, a cap CP installed on the rotation shaft in order to fix the shaft position and prevent bearing detachment, and a deep groove ball bearing 39 installed on the rotation shaft.

[0092] As shown in FIG. 8, the deep groove ball bearing 39 may be installed in different numbers, such as three installed on the left and four installed on the right depending on the stress concentration phenomenon.

[0093] The deep groove ball bearing 39 of FIG. 8 may have the same configuration and function as the deep groove ball bearing 37 of FIG. 7, and a detailed description is omitted.

[0094] FIG. 9 is a cross-sectional view showing a first guide roll GR1 of the asymmetric rolling device 100 of FIG. 1, and FIG. 10 is a cross-sectional view showing a state in which rolling oil 2 is directly injected into a first work roll WR1 through a rolling oil injecting groove portion 41 of the asymmetric rolling device 100 of FIG. 9.

[0095] As shown in FIGS. 9 and 10, the first guide roll GR1 of the asymmetric rolling device 100, 200, and 300 according to various embodiments of the present disclosure may include a contact portion 40 in which at least one rolling oil injecting groove portion 41 is formed and contacting the first idle roll IR1, a shaft portion 50 in which one end portion is fixed to a cassette body 81 and the other end portion is inserted into a concave portion 40a concavely formed at an end portion of the contact portion 40, and at least one self-aligning bearing 60 formed between the contact portion 40 and the shaft portion 50 so that a rotation center of the contact portion 40 may be aligned and rotated.

[0096] Here, the self-aligning bearing 60 may have a configuration in which an inner ring is formed to be tiltable based on an outer ring, and a ball or a roller is double installed to be inclined so as to be returned to the original position during tilting.

[0097] However, the self-aligning bearing 60 is not necessarily limited thereto, and a wide variety of forms of bearings that may rotate while withstanding the tilting load may be applied.

[0098] More specifically, for example, the rolling oil injecting groove portion 41 may include a circumferential linear groove portion formed in a ring-type linear groove shape along the circumference of the contact portion 40 so that the injected rolling oil 2 may pass through the rolling oil injecting groove portion 41, pass a first gap D1 between the first idle roll IR1 and the drive roll DR, and be directly injected into the first work roll WR1.

[0099] Therefore, as shown in FIG. 10, the injected rolling oil 2 may pass through the rolling oil injecting groove portion 41, pass the first gap D1 between the first idle roll IR1 and the drive roll DR, and be directly injected into the first work roll WR1 to facilitate the supply of the rolling oil 2, thereby increasing heat dissipation and reducing friction force to significantly improve the rolling performance.

[0100] FIG. 11 is a cross-sectional view showing another example of the rolling oil injecting groove portion 41 of the asymmetric rolling device 100 of FIG. 1.

[0101] As shown in FIG. 11, the rolling oil injecting groove portion 41 of the first guide roll GR1 may be formed in a spiral shape, a tapered portion 42 for preventing corner stress concentration may be integrally formed in a contact portion 40, and a plurality of self-aligning bearings 60 may be formed on a rotation shaft.

[0102] However, the self-aligning bearing 60 is not necessarily limited thereto, and a wide variety of forms of bearings that may rotate while withstanding the tilting load may be applied.

[0103] Therefore, the material to be rolled 1 that is rolled by the asymmetric rolling device 100, 200, and 300 of the present disclosure may include magnesium or a magnesium alloy having a hexagonal close-packed (HCP) structure. Recently, magnesium, which has been studied as a next-generation lightweight member, has a density of 1.74 g/cm.sup.3 which is lighter than iron having a density of 7.90 g/cm.sup.3 or aluminum having a density of 2.7 g/cm.sup.3, and may also have excellent specific strength and specific elastic modulus. In addition, magnesium has excellent absorption capability for vibration, shock, electromagnetic wave, etc. and excellent electrical and thermal conductivity, and thus it may be applied not only to lightweight material such as automobiles and aircrafts, but also to electronic industries such as mobile phones and laptops.

[0104] Meanwhile, the material to be rolled 1 in which the rolling is performed by the asymmetric rolling device 100, 200, and 300 of the present disclosure may also roll the same material to be rolled 1 a plurality of times. Performing such plurality of times of rolling may be performed to prevent problems that occur when a sudden rolling reduction is applied by sequentially applying a rolling reduction adjusted to an appropriate level to the material to be rolled.

[0105] At this time, the plurality of times means that the total number of rolling times of the material to be rolled 1 is two or more times by putting the material to be rolled 1 rolled by the work rolls WR1, WR2 into the same work rolls WR1, WR2 again or passing the material to be rolled 1 the work rolls WR1, WR2 provided in plural, and in this case, the process of putting the rolled material to be rolled 1 into the work rolls WR1, WR2 may include both continuous or intermittent cases.

[0106] In addition, the plurality of times may also include not only a case in which the material to be rolled 1 is physically separated from the work rolls WR1, WR2 and then fed again, but also a case in which the material to be rolled 1 is fed again between the work rolls as the rotation direction of the work rolls WR1, WR2 is reversed while still positioned between the work rolls WR1, WR2.

[0107] Therefore, it is preferable that the first idle roll IR1 and the guide roll GR1 are disposed at the front and the back of the above-described first work roll WR1, respectively.

[0108] Meanwhile, it is obvious that the material to be rolled 1 in which the rolling is performed by the asymmetric rolling device 100, 200, and 300 of the present disclosure, may be applied to any material that controls the texture of the rolled material in addition to the above-described magnesium or magnesium alloy. For example, it may be applied even when the material to be rolled 1 is a metal material having a hexagonal close-packed crystal structure including titanium Ti or titanium alloy, a metal material including aluminum, aluminum alloy, or FeSi alloy in which the crystal orientation of the rolled material affects magnetic properties.

[0109] The present disclosure has been described with reference to the embodiments illustrated in the drawings, but these embodiments are merely illustrative and it should be understood by a person with ordinary skill in the art that various modifications and equivalent embodiments can be made without departing from the scope of the present disclosure. Therefore, the true technical protective scope of the present disclosure should be determined based on the technical concept of the appended claims.