MAGNETIC ROLLING APPARATUS

Abstract: A rolling apparatus applied with magnetic force established between a main roller (11) and a presser roller (13) such that a workpiece (17) undergoes a uniform and predetermined pressure throughout the rolling process, and the magnetic force is controllable by regulating the electric direct current to the magnet. Several ways of establishing magnetic force where the main roller is non-magnetic material and the presser roller is metallic magnetic and where both rollers (11, 13) are metallic magnetic materials are disclosed.

Description: This invention relates according to the precharacterising part of claims 1 and 2 respectively to an apparatus for rolling metal foil, cloth, paper, on the like, for calendering. 2. Description of the Related Art Referring to Fig. 14, one conventional way of rolling metal foil or cloth for calendering is explained. Numerals 1, 2 and 3 denote rollers, numerals 5, 6 and 7 denote guide rollers, and numeral 4 denotes a workpiece. The workpiece 4 is guided by the guide rollers 5, 6 and 7 and rolled by the rollers 1, 2 and 3 respectively such that the workpiece 4 is flattened or calendered. Referring to Fig. 15, one conventional way of pressing the workpiece 4 is explained. A hydraulic pump 8 presses a bearing 1a which supports the roller 1 such that the workpiece 4 is pressed between rollers 1 and 2. It is also possible to press upwardly on a bearing 2a which supports the roller 2 such that the workpiece 4 is pressed in between rollers 1 and 2. However, when rollers 1, 2 and 3 are made of metal, they tend to deflect as shown in Fig. 15 because of the pressure applied to the bearings 1a or 21. So, it is impossible to clamp the workpiece between the rollers with a uniform pressure, resulting in poor performance. Further, the pressure exerted by the hydraulic pump 8 against the bearings 1a or 2a cannot always be maintained at a constant value, so the unbalanced pressure causes an unbalanced rolling as shown in Fig. 17. When one of the rollers 1, 2 and 3 is of an elastic material, for instance, plastic or the like, its surface is easily scratched resulting in a degraded workpiece. Further, since a plastic roller is not heat resistant, when the workpiece is heated during the rolling process, a plastic roller will deteriorate. To avoid the aforementioned disadvantages, some detecting means to detect the scratches in the workpiece is required, as well as frequent replacement of the deteriorated roller resulting DE-A-3404833 representing the closest prior art discloses rolling apparatus comprising two parallel work rollers, adapted to press a workpiece passing between the two rollers. At least one of the work rollers is movable and means are provided for controllably urging the or each movable roller towards the other to press the workpiece. According to one aspect of the present invention, there is provided a rolling apparatus comprising a main roller rotatably supported by a frame and a pressure roller rotatably supported by the frame, the pressure roller being urged towards the main roller under a force, the workpiece being arranged to pass between the pressure and main rollers so as to be pressed, characterised in that the main roller is of non-magnetic material and is hollow, in that a magnet is provided inside the hollow main roller and in that the pressure roller is of magnetic material so that the pressure roller is urged by said magnet towards the main roller to provide said force. According to another aspect of the present invention, there is provided a rolling apparatus comprising a frame and two cylindrical main rollers rotatably supported adjacent and parallel to each other by the frame, at least one of said main rollers being mounted so as to be movable towards and away from the other main roller and being urged towards the other main roller under a force, the workpiece being arranged to pass between the main rollers so as to be pressed, characterised in that the main rollers are of magnetic material, in that the frame has two yokes, each main roller being disposed adjacent to a respective yoke, each yoke having a solenoid wound thereon for magnetising the respective yoke by generating magnetic flux perpendicular to the direction of motion of the workpiece and along a line through the centres of the two main rollers, one of the yokes being magnetised as a north and the other as a south pole, the main rollers being magnetised by the magnetic flux generated by the solenoids so as to be attracted to each other by said force. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following description of the preferred embodiment thereof taken in conjunction with the accompanying drawings in which like reference numerals denote like members and of which: Fig. 1 is a side view of a rolling apparatus according to the first embodiment of the present invention. Fig. 2 is a partial section view of the rollers shown in Fig. 1; Fig. 3 is a partial section view of a yoke portion in a main roller shown in Fig. 2; Fig. 4 is a perspective section view of a yoke shown in Fig. 3; Fig. 5 is an explanatory view showing a magnetic flux line along an axial direction, and around a circumference of a yoke shown in Fig. 3 and Fig. 4; Fig. 6 is a perspective view of a yoke in a main roller according to the second embodiment of the present invention; Fig. 7 is an explanatory view showing a magnetic flux along an axial line and around a circumference of the yoke shown in Fig-. 6; Fig. 8 is a perspective view of a yoke according to the third embodiment of the present invention; Fig. 9 is an explanatory drawing showing magnetic flux along an axial line and around a circumference of a yoke shown in Fig. 8; Fig. 10 is a side sectional view of a rolling apparatus according to the fourth embodiment of the present invention; Fig. 11 is a side section view of a rolling apparatus according to the fifth embodiment of the present invention; Fig. 12 is a side sectional view of a rolling apparatus according to the sixth embodiment of the present invention; Fig. 13 is a side view of a rolling apparatus according to the seventh embodiment of the present invention; Fig. 14 is a side sectional view of a conventional rolling apparatus; Fig. 15, Fig. 16, Fig. 17 are explanatory drawings showing inconveniences of operation associated with a conventional rolling apparatus. DETAILED DESCRIPTION OF THE INVENTION Referring to the accompanying drawings, the preferred embodiments of the present invention will be described in detail. Referring to Figs. 1 to 5, the first embodiment of the present invention will be described hereinafter. Numeral 11 (Fig. 2) denotes a main roller which is tubularly shaped and is placed in opposition relation with other pressure rollers and made of non-magnetic materials. The roller rim is preferably thin so that a sufficient magnetic attractive force may be established between the main roller 11 and a pressure roller 13. Although a thin roller rim is preferable, it should be mechanically strong enough to undergo the rolling pressure without excessive deterioration. The main roller 11 is rotatably supported by a frame 12. A suitable number of the pressure rollers 13 which are made of magnetic material are provided around the circumference of the main roller 11. The pressure rollers 13 are rotatably supported by the frame and in pressing relation against the main roller 11. In a hollow portion of the main roller 11, a yoke 14 which consists of magnetic material is inserted and both ends of the yoke 14 are fixed to the frame 12. The yoke 14 is provided with several solenoids 22 which are in opposing relation to the pressure rollers 13. Magnetic flux caused by these solenoids 22 is shown in Fig. 5. A suitable number of guide roller 16 are provided in planetary relation to the main roller 11, and these guide rollers 16 are rotatably supported by the frame 12. Referring to Fig. 1, a workpiece 17 is inserted and passed between the main roller 11 and the pressure roller 13 being guided by the respective guide roller 16. Repeating several equivalent path ways, the workpiece 17 is finally drawn out. The yoke 14 is provided with salient poles 21a which establish a magnetic pole and also with grooves 21b which accommodate the solenoids 22 shaped annularly with the winding coil accommodated therein. The magnetic flux in the yoke, established by the solenoids 22, is shown in Fig. 5. Along the axial line of yoke 14, N-pole and S-pole are alternately established, and around the circumference of the yoke 14, N-pole or S-pole is established. In this drawing, N-pole is shown. It is also possible to eliminate the guide rollers so that the workpiece 17 is advanced along the circumference of the main roller 11 being inserted and pressed between the main roller 11 and the presser roller 13. When the main roller 11 is rotated by any driving source, the workpiece 17 is rolled and advanced. During the rolling process, each pressure roller 13 is attracted to the main roller 11 because of a magnetic force established by the solenoids 22. The pressure roller 13 is rotated by the fractional force between the pressure roller 13 and the workpiece 17. Thus, the pressing of workpiece between the pressure rollers 13 and the main roller 11 is conducted by the magnetic force established by the solenoids 22, and the magnetic force is controlled by regulating the electric direct current to the solenoids. Referring to Fig. 6 and Fig. 7 the second embodiment of the present invention will be described. A yoke 26 is provided with solenoids 25 and with salient poles 26a which establish the magnetic poles and with grooves 26b in which solenoids are accommodated. The magnetic flux in the yoke 26 is shown in Fig. 7. Along the axial line of the yoke 26, N-pole and S-pole are alternately established, and around the circumference of the yoke 26, N-pole or S-pole is established. In this drawing, N-pole is shown. Referring to Fig. 8 and Fig. 9, the third embodiment of the present invention will be described. A yoke 31 is provided with solenoids 32 and salient poles 31b established by the solenoids and grooves 31a grooved in parallel with the axial line of yoke such that the solenoids 32 are accommodated therein. Under such a construction of the yoke 31, the magnetic flux will be as shown in Fig. 9. Along the axial line of yoke 31, N-pole or S-pole is established. In this drawing Fig. 9, N-pole is shown. Around the circumference of yoke 31, N-pole or S-pole is established. According to the above described three embodiments, the yokes 14, 26 and 31 establish a uniform magnetic attractive force in a direction perpendicular to the axis of a yoke such that the presser roller is attracted to the main roller with a uniform attractive force established along its axial line throughout. The uniform magnetic attractive force can be easily controlled by regulating the electric current to the solenoids. In this manner the pressing due to the pressure roller 12 can be adjusted. It is also possible to use a permanent magnet in lieu of solenoids 22, 25 and 32. Referring to Fig. 10, the fourth embodiment of the present invention will be described. Two main rollers 36, 37 are placed in opposing relation and the distance between these two rollers is adjustable. Electromagnets 38 and 39 are disposed such that an attractive force between these two main rollers 36, 37 is established. To establish the attractive force, the main rollers 36, and 37 are made of magnetic material and are adapted to be moved in the direction of the attractive force and rotatably supported by a frame 40 and 41. One of the main rollers is driven by a belt 42 connected to a drive source 43. The electric magnets 38 and 39 are provided with yokes 44, 45 respectively which are fixed to the frames 40, 41. The yokes 44, 45 are provided with solenoids 46, 47 respectively. Salient poles 44a, 45a are placed adjacent to the main rollers 36 and 37 respectively. It is so adapted that when the electromagnet 39 establishes a N-pole, the electromagnet 38 establishes a S-pole so that both main rollers 36 and 37 attract each other. According to the fourth embodiment, when a workpiece 49 is inserted between the main rollers 36 and 37, and solenoids 46 and 47 are energized, the main rollers 36 and 37 approach each other and clamp the workpiece 49. Further, when the drive motor 43 energizes, the main roller 36 rotates and the workpiece 49 is advanced by the fractional force established between the workpiece and the main roller. Thus the workpiece is rolled and the pressing force by these main rollers is controlled by regulating the electric current to the solenoids 46 and 47. Referring to Fig. 11, the fifth embodiment of the present invention will be explained. A middle roller 50 is placed between main rollers 36 and 37. The middle roller 50 is made of a magnetic material, and is attracted to, in contacting relation with, both main rollers 36, 37 when solenoids 46, 47 are energized. When the main rollers 36 is rotated by a belt 42 driven by a motor 43, a workpiece 49 clamped between the middle roller 50 and the main rollers 36 and 37 is advanced by the fractional force established between the middle roller 50 and the main rollers 36 and 37. According to the fifth embodiment, several guide rollers 48 are placed such that the workpiece 49 is guided between the middle roller and the main roller. When solenoids 46 and 47 are energized, the main roller 36 and 37 tend to approach each other, and the workpiece 49 is pressed between the main roller and the middle roller. Further, when the main roller 36 rotates being driven by a belt 42 connected to a motor 43, the workpiece is advanced by the frictional force established between the main roller and the middle roller. The pressing force against the workpiece can be controlled by regulating the electric current to the solenoids 46 and 47. Referring to Fig. 12 the sixth embodiment of the present invention will be described. Two middle rollers 50a, 50b made of a magnetic material are placed between main rollers 36, and 37. The construction of the sixth embodiment is very similar to that of the fifth embodiment. A workpiece 49 is inserted between the middle roller 50a and a main roller 37 and is drawn out and finally inserted between the middle roller 50a and a main roller 36. When solenoids 46, and 47 energize, an attractive force is established between the main rollers 36, and 37 and between the middle roller 50a, 50b. When the main roller 36 is rotated by a belt connected to a motor 43, the workpiece 49 is advanced by the friction force established between the workpiece and the main roller. The pressing force against the workpiece can be controlled by regulating the electric current to the solenoids 46, and 47. Referring to Fig. 13, the seventh embodiment of the present invention will be described. One object of the seventh embodiment is to increase the quantity of rolling steps. Several auxiliary rollers 51 are disposed between main rollers 36, and 37. The auxiliary rollers 51 are made of magnetic material. Increasing the quantity of auxiliary rollers 51 cause the magnetic force established between solenoids 46, and 47 to be weakened. To strengthen the weakened magnetic force, auxiliary solenoids 52 are placed proximate the auxiliary rollers 51. The auxiliary rollers 51 are rotatably supported by frames 53 and are adapted to be moved vertically. The frames 53 are disposed between the main rollers 36, and 37, and are replaceable. By providing yokes on the frames 53 or substituting the frame for the yoke, the auxiliary solenoids 52 can be eliminated. It is also possible to establish the necessary magnetic force auxiliary solenoids 52. The direction of magnetic force established by the auxiliary rollers 51 is in accordance with the direction of magnetic force established by the solenoids 52. According to the seventh embodiment, as shown in Fig. 13, several guide rollers 48 are located at suitable positions, and a workpiece 49 is inserted between the main roller 37 and the auxiliary roller 51, and further between the main roller 36 and the auxiliary roller 51 being rolled and guided steppingly. When the solenoids 46, and 47 and the auxiliary solenoids 52 are energized, the attractive force between the main rollers 36, and 37 and between the auxiliary rollers 51 are established. When the main roller 36 is rotated by a belt 42 connected to a drive motor 43, the workpiece 49 is rolled by the main rollers and auxiliary rollers, guided by guide rollers. The workpiece 49 is advanced by the frictional force established between the workpiece and the opposing roller. In this embodiment, the solenoids 46, and 47 and the auxiliary solenoids 52 are used but these solenoids can be replaced by permanent magnets. According to the aforementioned embodiments, the presser rollers undergo the forced drive. As aforementioned, according the present invention of a rolling apparatus applying a magnetic force between the main roller and the presser roller, uniform pressure can be applied perpendicularly on the workpiece clamped between the main roller and the pressure roller and the pressure can be freely controlled by regulating the electric current to the solenoid. Further, where both the main roller and the pressure roller are made of metals, the workpiece is pressed between the main roller and the presser roller by the magnetic attractive force established therebetween, and the problem of shorter roller life is eliminated although the pressing force is considerably strong, and the frequency of exchanging rollers becomes less because the rollers are made of hard metals. As many apparently widely different embodiments of this invention amy be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

Claims: A rolling apparatus comprising a main roller (11) rotatably supported by a frame and a pressure roller (13) rotatably supported by the frame, the pressure roller (13) being urged towards the main roller (11) under a force, the workpiece being arranged to pass between the pressure and main rollers so as to be pressed, characterised in that the main roller is of non-magnetic material and is hollow, in that a magnet (22) is provided inside the hollow main roller (11) and in that the pressure roller (13) is of magnetic material so that the pressure roller (13) is urged by said magnet (22) towards the main roller to provide said force. A rolling apparatus comprising a frame (40, 41) and two cylindrical main rollers (36, 37) rotatably supported adjacent and parallel to each other by the frame (40, 41), at least one of said main rollers being mounted so as to be movable towards and away from the other main roller and being urged towards the other main roller under a force, the workpiece (49) being arranged to pass between the main rollers (36, 37) so as to be pressed, characterised in that the main rollers (36, 37) are of magnetic material, in that the frame has two yokes (44, 45), each main roller (36, 37) being disposed adjacent to a respective yoke (44, 45), each yoke having a solenoid (46, 47) wound thereon for magnetising the respective yoke by generating magnetic flux perpendicular to the direction of motion of the workpiece (49) and along a line through the centres of the two main rollers (36, 37), one of the yokes being magnetised as a north and the other as a south pole, the main rollers (36, 37) being magnetised by the magnetic flux generated by the solenoids (46, 47) so as to be attracted to each other by said force. A rolling apparatus according to claim 2, characterised by comprising a middle roller (50) rotatably supported on the frame (40, 41) and disposed adjacent to each of the two main rollers (36, 37), and a plurality of guide rollers (48) mounted rotatably on said frame (40, 41) at positions remote from the middle roller (50), the workpiece (49) being guided by the guide rollers (48) between one of the two main rollers (40, 41) and the middle roller (50) and subsequently guided by the guide rollers (48) between the main roller and the middle roller (50). A rolling apparatus according to claim 2, characterised by comprising two middle rollers (50a, 50b) rotatably supported on the frame, each middle roller being disposed adjacent to said two main rollers (36, 37), and a plurality of guide rollers (48) rotatably mounted on the frame (40, 41) at positions remote from the middle rollers (50a, 50b), the workpiece being guided by the guide rollers (48) between one of the two main rollers (36, 37) and the two middle rollers and then subsequently guided between the other main roller and the two middle rollers. A rolling apparatus according to claim 2, characterised by comprising a plurality of auxiliary rollers (51) of magnetic material disposed one after the other between the two main rollers (36, 37), a plurality of auxiliary frames (53) disposed between the two main rollers and each rotatably supporting a respective auxiliary roller (51), a plurality of solenoids (52) each disposed on a respective auxiliary frame (53) for magnetising the respective auxiliary roller (51), and a plurality of guide rollers (48) rotatably supported on the frame at locations remote from the auxiliary rollers (51), the workpiece (49) being guided by the guide rollers (48) between one of the two main rollers and one of the auxiliary rollers (51) and then guided by the guide rollers (48) between each pair of auxiliary rollers (51) until it passes between the other main roller and the adjacent auxiliary roller (51). A rolling apparatus according to any of claims 2 to 5, characterised in that the pressing force applied to the workpiece (49) can be controlled by controlling the electric current supplied to the solenoids (46, 47).

Inventors: SUZUKI, HIDEO, SUZUKI, HIDEO, C/O BELLMATIC LIMITED
Applicants: BELLMATIC LIMITED
Application year: 1990
Main classification: B21B13
IPC codes: B21B27, F16C13, B21B1, B21B13, D21G1, B21B31, D06C15