JP3296322B2 - Gravure printing roll and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight aluminum gravure printing roll having good shape accuracy and a method of manufacturing the same.

[0002]

2. Description of the Related Art A gravure printing roll has a structure in which flanges are attached to openings at both ends of a printing drum which forms irregularities corresponding to a printing pattern on the outer peripheral surface, and bearings are provided in holes formed in the flanges. In recent years, a roll made of aluminum or aluminum alloy (hereinafter, collectively referred to as aluminum) having excellent lightweight properties has been used instead of iron. A gravure printing roll made of aluminum is usually manufactured by a process as shown in FIG. For example, 6000 series-
A roll 10 serving as a base of a printing surface is prepared with an extruded pipe of T5 material, and a DC cast product of 4000 series-T6 material is cut out to prepare a flange 20 (a). In order to spigot-connect the flange 20 to the roll 10, an inner peripheral surface of the end of the roll 10 is cut to form the spigot portion 11, and a hole 21 for mounting a rotating shaft is drilled in the flange 20 (b).
Flange 20 is attached to the spigot part 11 with a step by cutting.
And the flange 20 is joined to the end of the roll 10 by press fitting, shrink fitting, bonding, welding, or the like (c). Next, the outer peripheral surface 12 of the roll 10 and the outer surface 22 of the flange 20 are chamfered (d), and the surfaces are activated by zincate treatment or the like, and then a Cu plating layer of about 60 to 150 μm is formed on the outer peripheral surface 12 and the outer surface 22. 31 is formed (e) and the surface is polished (f) to complete the roll manufacturing process.

When the manufactured roll is used for printing, a thick Cu plating layer 32 used as a printing surface is provided on the Cu plating layer 31 (g). Thick Cu plating layer 32
Is applied with a thickness of 80 to 100 μm. When used for repeated printing, the Cu plating layer 31 is formed by ballad plating so that the thick Cu plating layer 32 can be easily peeled off.
After immersing the roll 10 formed with the above in a silver nitrate solution, the thick Cu plating layer 32 is formed. When the thick Cu plating layer 32 is semipermanently used for a printing surface, the thick Cu plating layer 32 is provided directly on the Cu plating layer 31. Thick film C
A concave portion 33 serving as an ink pit during gravure printing is formed in the u plating layer 32 (h). The recess 33 is a sculpture,
It is formed to a depth of 30 to 60 μm by etching or the like. The thick film Cu plating layer 32 in which the concave portion 33 is formed is subjected to Cr plating in order to increase durability, and gravure printing is performed as a printing surface (i). When changing the printing surface, the thick film Cu
The plating layer 32 is peeled off, a thick Cu plating layer 32 is newly provided on the Cu plating layer 31, and a concave portion 33 having a required pattern is formed (j).

[0004]

During the printing operation, gravure printing rolls are frequently replaced. The workability of the roll exchange can be improved by using a lightweight aluminum roll, but the weight reduction is not limited to the selection of the material, and the roll 10 needs to be thinner. As the thickness of the roll 10 is reduced, it is also desired to improve the joining methods, such as press-fitting, shrink fitting, bonding, and welding, which have been conventionally employed. For example, in the case of press fitting or shrink fitting, it is inevitable that the end opening of the roll 10 is opened, and it is difficult to reduce the wall thickness to 10 mm or less in consideration of the joining strength. In the method of bonding the flange 20 to the roll 10, the adhesive may be dissolved in the solvent of the printing ink, and the bonding strength may be reduced.

[0005] It is known that the flange 20 is melt-bonded to the roll 10 (Japanese Patent Laid-Open No. 1-145196), but distortion tends to occur in the welded portion due to heat input during welding. When the thickness of the roll 10 is reduced, the difference in heat capacity between the roll 10 and the flange 20 increases, so that the distortion generated in the roll 10 also increases. Further, when a heat-treated alloy material is used, the softened area of the heat-affected zone is widened and the strength is reduced. By the way, in the gravure printing roll, if the outer peripheral surface 12 including the vicinity of the end portion is distorted, the ink other than the engraved portion cannot be sufficiently removed by the scraper K (FIG. 6) or the like, resulting in poor printing. The distortion is also a factor that hinders the smooth rotation of the gravure printing roll. Therefore, in the case of ordinary welding, the roll 10 is manufactured by increasing the thickness of the roll 10 and welding it to the flange 20, and after welding, cutting the surface of the roll 10 deeply. However, in this welded product, the heat input is high and the temperature is high, and good dimensional accuracy cannot be obtained due to thermal expansion. Deep surface cutting causes a reduction in productivity in making the roll 10 thinner.

[0006]

SUMMARY OF THE INVENTION The present invention has been devised to solve such a problem. By improving the heat balance between the roll and the flange, the present invention can reduce the thickness of the roll. An object of the present invention is to provide a gravure printing roll that suppresses the occurrence of welding distortion, is lightweight, and can be easily replaced. The gravure printing roll of the present invention, in order to achieve the object, an aluminum roll having a spigot portion formed at the inner surface of both ends, an aluminum flange fitted to the spigot portion and welded to the inner peripheral surface of the aluminum roll. Wherein a groove or a concave portion for reducing diffusion of heat energy applied during welding by heat transfer is formed on the outer surface and / or outer peripheral surface of the flange near the welded portion. A plurality of grooves or a single groove may be formed on the outer surface or outer peripheral surface of the flange, and may be either a continuous groove or an intermittent groove.

[0007] This gravure printing roll forms a stepped inset portion on both inner surfaces of an aluminum roll,
Manufactured by fitting a flange with grooves or recesses on the outer surface or outer peripheral surface located near the welded part into the spigot part of the aluminum roll, and welding between both end surfaces of the aluminum roll and the outer surface of the flange. Is done.
The roll and the flange can be welded at a high speed at a welding speed of 2 to 7 m / min. In the case of high-speed welding, the influence of thermal imbalance between the roll and the flange is reduced, so that welding distortion is reduced without forming a groove or a recess in the flange. However, when the improvement of the heat balance by forming the groove or the concave portion and the high-speed welding are used together, the welding distortion is further reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS When the flange 20 is welded to the roll 10, distortion occurs on the outer peripheral surface of the roll 10 at the welded portion due to poor heat balance between the roll 10 and the flange 20. The roll 10 usually has a thickness of 20 to
Since the thickness is thinner than that of the flange 20 of 30 mm, the heat input at the time of welding becomes larger in the roll 10 by an amount corresponding to a smaller heat transfer amount than in the flange 20. Therefore, the roll 10 which becomes a thin joining portion is exposed to a high temperature for a long time. As a result, the thermal expansion of the roll 10 increases, and remains as distortion after welding. As the roll 10 is made thinner for weight reduction, the heat balance becomes more disturbed, and the occurrence of welding distortion becomes remarkable. Therefore, in the present invention, by forming a groove or a concave portion that reduces the effective heat capacity of the flange 20 that affects the thermal deformation during welding, or by adopting high-speed welding that does not give a large amount of heat to the welded portion. Roll 10
To improve the heat balance between
Welding distortion that tends to occur at zero is suppressed.

The groove formed on the outer surface 22 of the flange 20 is, for example, a ring-shaped continuous groove 23 (FIG. 2) formed near the outer peripheral surface of the flange 20 near the welded portion W between the roll 10 and the flange 20. is there. The formation of the continuous groove 23 narrows the heat flow path through which the heat input to the welded portion W escapes to the main body side of the flange 20, and reduces the effective heat capacity of the flange 20. As a result, the heat balance between the roll 10 and the flange 20 is improved, and the thermal deformation due to the heating of the roll 10 and thus the welding distortion are suppressed. The size of the continuous groove 23 varies depending on the material and size of the roll 10 and the flange 20 to be welded and the processing conditions, and is not determined uniquely. For example, the groove width is 3 to 30 mm and the groove depth is 2 to 2.
10 mm, 3 to 15 inside the outer peripheral surface 28 of the flange 20
When formed at the position of mm, the effective heat capacity is effectively reduced.

Instead of the continuous groove 23, the recess 24 (FIG. 3) may be formed in the central portion by increasing the thickness only in the vicinity of the welded portion W. The groove and the concave portion are the intermittent groove 25 (FIG. 4a) or the intermittent concave portion 2.
6 (FIG. 4b) on the outer surface of the flange 20, and a plurality of continuous grooves 23 or intermittent grooves 25 may be formed concentrically. Furthermore, even if the circumferential groove 27 (FIG. 5) is formed on the outer peripheral surface 28 of the flange 20, the roll 10 and the flange 20
And the heat balance is improved. Similarly, a plurality of circumferential grooves 27 can be formed on the outer peripheral surface 28 of the flange 20 along the center axis direction. The grooves and recesses are effective not only for improving the heat balance, but also for reducing the weight of the flange 20, which is effective for reducing the weight of the gravure printing roll. Above all, except for the vicinity of the outer peripheral surface 28, the concave portion 24 that makes the flange 20 substantially thin has a great effect of weight reduction.

The heat balance between the roll 10 and the flange 20 is also improved by high-speed welding. The inventors of the present invention disclosed in Japanese Patent Application Laid-Open No. 8-197225 high-speed welding of aluminum materials.
The welding method introduced in the official gazette, the welding speed is 2-7m
When performing TIG or MIG welding at a high setting of / min, deformation and distortion due to welding are suppressed, and a weld bead having a good appearance and a narrow width is formed. Due to the high-speed welding with increased energy density, the roll 10 and the flange 20 are locally heated for a short time, and the total heat input is reduced, so that the heat balance between the roll 10 and the flange 20 is improved. As a result, distortion of the roll 10 that tends to occur after welding is suppressed.

In high-speed welding, MIG having a high energy density is used.
Using welding, welding current 200-400A, welding voltage 19
The roll 10 and the flange 20 are welded at about 30V. During welding, the weld is shielded with an inert gas as necessary. By adopting such welding conditions, the welding speed is reduced to 2
It is possible to increase the height to about 7 m / min, and a welded portion W without welding distortion is formed. By setting the welding speed to 2 m / min or more, the welded portion W is formed before the heat input is diffused into the flange 20 by the heat transfer, so that the distortion generated in the roll 10 is also reduced. However, at a welding speed exceeding 7 m / min, the welding conditions become unstable, and a sound welded portion W cannot be obtained. High-speed welding is performed by forming a groove or
Combined with reducing the effective heat capacity of zero,
Generation of welding distortion is further suppressed, and a sound welded portion W is formed. When welding the flange 20 to the roll 10 according to the present invention, a welded portion W with suppressed welding distortion is formed. Therefore, the surface grinding of the welded roll 10 is reduced or omitted, and a gravure printing roll that sufficiently satisfies the required characteristics even when the roll 10 is thinned can be obtained.

[0013]

EXAMPLE 1 An aluminum alloy extruded pipe (6063-T5 material) having a diameter of 194 mm, a circumference of 609 mm, and a wall thickness of 7 mm was used as the roll 10. As the flange 20, a disk having a diameter of 180 mm and a height of 20 mm was cut out from an aluminum DC casting, and a rotary shaft mounting hole 21 having a tapered center portion was opened. The inner peripheral surface of the end of the roll 10 is cut and processed to have an axial length of 20 mm and a step of 1.5 m.
The m spigot part 11 was formed. A groove width of 5 m is provided on the outer surface 22 of the flange 20 at a position 8 mm away from the outer peripheral surface 28.
m, a continuous groove 23 having a groove depth of 5 mm was formed. Flange 2
0 was fitted into the spigot portion 11 of the roll 10, and welding was performed at a welding current of 200A, a welding voltage of 23V, and a welding speed of 0.6m / min. When the shape of the roll 10 was measured after welding,
The roundness was 0.05 mm and the straightness was 0.1 mm / m, and the deformation due to welding distortion was very small. Therefore, 0.
After adjusting the outer peripheral surface of the roll 10 with a surface cutting amount of 25 mm, it could be sent to the next Cu plating layer 31 forming step (FIG. 1e).

On the Cu plating layer 31, a film thickness of 80 to 120
A thick Cu plating layer 32 having a thickness of μm was formed, a concave portion 33 for gravure printing was formed in the thick Cu plating layer 32, and Cr plating was performed. The obtained gravure printing roll R is immersed in the ink I stored in the ink pan P as shown in FIG.
The pressing roller B was opposed. While continuously feeding the printing sheet S between the gravure printing roll R and the pressing roll B, the gravure printing roll R is rotated clockwise to lift up the ink I, and scraping off excess ink I with the scraper K. Attached to the printing sheet S. Observation of the print pattern applied to the printing sheet S revealed that the pattern of the concave portion 33 applied to the gravure print roll R was accurately transferred, and the print finish was uniform in the width direction.

For comparison, the same flange 20 was used except that the continuous groove 23 was not provided, and was welded to the roll 10 under the same conditions. Between the roll 10 and the flange 20 after welding, the flange 20 was not melted due to insufficient heat input and could not be joined.

[0016]

Embodiment 2 The same roll 10 and flange 2 as in Embodiment 1
0 and the flange 2 on the spigot part 11 of the roll 10
0 was inserted, and high-speed welding was performed at a welding current of 310 A, a welding voltage of 26 V, and a welding speed of 3 m / min. When the shape of the roll 10 was measured after welding, the roundness was 0.02 mm and the straightness was 0.04 mm / m, and the deformation caused by welding distortion was very small. Therefore, after adjusting the outer peripheral surface of the roll 10 with a surface cutting amount of 0.1 mm, the roll 10 could be sent to the next Cu plating layer 31 forming step (FIG. 1E). For comparison, the welding speed was set to a normal speed of 0.6 m / min.
Was welded to the roll 10. The roll 10 after welding has deteriorated in roundness of 0.4 mm and straightness of 1 mm / m.
In order to correct the outer peripheral surface of the roll 10 into a perfect circle and a straight line, a surface cutting amount of 2.5 mm was required.

[0017]

As described above, in the gravure printing roll of the present invention, the flange is welded to the roll while the heat balance between the roll and the flange is improved. Therefore, welding distortion, which is likely to be caused by heat input during welding, is suppressed, and surface cutting of the roll after welding is reduced or omitted. Therefore, a thin roll can be used, and the handleability of the gravure printing roll in which the roll is frequently changed is improved in combination with the fact that the roll is frequently made of aluminum.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram of a gravure printing roll

FIG. 2 is a partial cross-sectional view of a gravure printing roll obtained by welding a flange having a continuous groove to the roll according to the present invention (a) and a perspective view of the flange (b).

FIG. 3 is a partial cross-sectional view of a gravure printing roll obtained by welding a flange having a concave portion to the roll according to the present invention (a) and a perspective view of the flange (b).

FIG. 4 shows a flange provided with an intermittent groove (a) or an intermittent recess (b).

FIG. 5 is a partial cross-sectional view of a gravure printing roll obtained by welding a flange having a groove on an outer peripheral surface to the roll (a) and a perspective view of the flange (b).

FIG. 6 is a schematic diagram of a main part of a gravure printing apparatus.

[Explanation of symbols]

10: Roll 11: Inlay part 12: Outer peripheral surface 20: Flange 21: Rotating shaft mounting hole 22:
Outer surface 23: continuous groove 24: concave 25: intermittent groove 26: intermittent concave 2
7: circumferential groove 28: outer peripheral surface 31: Cu plating layer 32: thick film Cu plating layer 3
3: recess for ink pit

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Akiya 2-2-2-20 Higashi-Shinagawa, Shinagawa-ku, Tokyo Inside Nihon Light Metal Co., Ltd. (72) Keiichi Sato 2-2-2, Higashi-Shinagawa, Shinagawa-ku, Tokyo No. Nippon Light Metal Co., Ltd. (56) References JP-A-61-272148 (JP, A) JP-A-62-13627 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41F 13/11 B23K 9/173 B23K 9/23 B41N 1/06 B23K 103: 10

Claims (6)

(57) [Claims] 1. An aluminum roll having a spigot portion formed on the inner surface of both ends, and an aluminum flange fitted to the spigot portion and welded to the inner peripheral surface of the aluminum roll. A gravure printing roll in which a groove or a concave portion for reducing diffusion due to heat transfer is formed on an outer surface and / or an outer peripheral surface of a flange near a welded portion. 2. The gravure printing roll according to claim 1, wherein one or more continuous or interrupted grooves are formed on the outer surface of the flange concentrically with the outer peripheral surface of the flange. 3. The gravure printing roll according to claim 1, wherein one or more grooves extending from the outer peripheral surface of the flange toward the center are formed on the outer peripheral surface of the flange. 4. The gravure printing roll according to claim 1, wherein a concave portion having a step from the vicinity of the welded portion is formed on the outer surface of the flange. 5. A flange formed with a stepped inner surface on both inner surfaces on both sides of an aluminum roll, and a groove or a recess formed on an outer surface or an outer peripheral surface located near a welded portion, is fitted into the inner surface of the aluminum roll. And a method for manufacturing a gravure printing roll for welding between both end surfaces of an aluminum roll and an outer surface of a flange. 6. A stepped spigot portion is formed on both inner surfaces of an aluminum roll, and an aluminum flange is fitted into the spigot portion, and a welded portion between both end surfaces of the aluminum roll and the outer surface of the flange is welded. Speed 2
A method for producing a gravure printing roll, comprising welding at 7 m / min.