JP2005186430A - Grooved kneading roller for printing and ink arrangement using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make uniform the amount of transfer of ink in the axial direction of a kneading roller for printing and also onto upper and lower plates and thereby to make the density of printed matter stable. <P>SOLUTION: This grooved kneading roller for printing has at least one or more first grooves formed in the surface of the roller and at least one or more second grooves so formed as not to intersect the first grooves. The first and second grooves form prescribed angles (θ) to the axial direction of the kneading roller, and they are so formed as to extend to the opposite ends of the kneading roller, at one end thereof at least. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a kneading roller for printing which is provided with a groove for uniformly transferring ink in a printing machine, and an ink supply apparatus using the same.

  In general, an ink supply device of a printing press has a structure as shown in FIG. 1, and the unevenness of the ink transfer amount is reduced by the gold roller i and the gold roller j being stroked in the roller axial direction. . (Hereafter, this is called a single inker.)

Further, as shown in FIG. 2, an ink supply device has been devised that supplies ink from two different ink fountains to two upper and lower plates via one roller. (For example, Patent Document 1) This ink supply apparatus is structurally designed so that the amount of ink transferred to the upper and lower plates is equal due to the effect of the roller g.
(Hereafter, this is called a double inker.)

  As a technology to reduce ink density unevenness in the axial direction of the roller, spiral grooves are formed on the diagonal line, and the ink is scraped off at the edges of the intersections, and the ink is transferred in the axial direction by evenly dispersing the edges. The amount is made uniform. (For example, Patent Document 2)

JP 2000-85095 A JP 2002-52694 A

However, in a single inker, since the ink transfer amount in the axial direction is uniform only in a range corresponding to the stroke amount in the above structure, in the case of multi-sided printing such as securities, the entire surface can be made to have a uniform ink transfer amount. Have difficulty.
Further, in the double inker, the amount of ink transferred to the lower plate increases due to the influence of gravity or the like, and a phenomenon that the density of the printed matter becomes unstable has occurred.

  Conventionally, as a countermeasure against this, the nip width (roller-to-roller) of the lower plate printing rollers a ″ and b ″ in FIG. 2 (which is a roller for applying ink to the printing plate, hereinafter referred to as a printing roller). The contact width when contacting with a certain pressure, hereinafter referred to as the nip width), or by adjusting the upper and lower ink transfer amounts by increasing the nip width of the upper printing rollers a ′ and b ′. Was. However, with such an adjustment method, it takes time to adjust the plate-forming roller and the work efficiency is poor. Further, since there is a difference in thermal expansion between the upper and lower plate form rollers, the difference in the amount of ink transfer is not completely eliminated. Furthermore, since the plate-forming roller having a larger nip width is likely to thermally expand during printing, there is a problem that the contact with the plate surface becomes strong and the plate surface is clogged with excess ink.

  The technique disclosed in Japanese Patent Application Laid-Open No. 2002-52694 is not intended to reduce the difference in the amount of ink transferred to the upper and lower plates, so it is very difficult to process in this way in consideration of the ink transfer rate to the upper and lower plates. When applied to the printing kneading roller f shown in FIG. 1, and the printing kneading roller f ′ and the printing kneading roller f ″ shown in FIG. It is presumed that durability cannot be obtained.

  The present invention has been proposed in consideration of such circumstances, and it is possible to make the ink transfer amount in the roller axis direction uniform and uniform the ink transfer amount to the upper and lower plates, thereby stabilizing the density of the printed matter. Is an issue.

The kneading roller for printing provided in the ink supply section of the printing machine was subjected to the following groove processing.
A printing kneading roller provided in an ink supply unit of a printing press, wherein the at least one first groove formed on the surface of the printing kneading roller is formed so as not to intersect the first groove. The kneading roller has at least one or more second grooves, and the first groove and the second groove form predetermined angles (θ) and (θ ′) with respect to the axial direction of the printing kneading roller. A kneading roller for printing subjected to groove processing, characterized in that at least one end of a first groove and a second groove is formed up to both ends.
Here, the first groove and the second groove of the printing kneading roller include not only continuous grooves but also intermittently formed grooves, and are not limited to straight lines.

  In the present invention, the predetermined angle (θ) of the first groove and the predetermined angle (θ ′) of the second groove are −90 ° <θ ′ <0 ° with respect to the axial direction of the printing kneading roller. And a kneading roller for printing with groove processing, characterized in that 0 ° <θ <90 °.

  The present invention is also a printing kneading roller subjected to groove processing, wherein the first groove and the second groove are symmetrical with respect to the roller axis, and the groove width and the number of grooves are the same.

  In addition, the present invention is a kneading roller for printing that has been subjected to groove processing, wherein the bottom surfaces of the first groove and the second groove are curved surfaces.

  Furthermore, the present invention is an ink supply device comprising a printing kneading roller subjected to the groove processing described above.

According to the present invention, in the single inker, the ink transfer amount in the axial direction of the printing kneading roller f can be made uniform.
Further, in the double inker, the ink transfer amount in the axial direction of the printing kneading roller f ′ and the printing kneading roller f ″ can be made uniform, and the difference in the ink transfer amount between the upper and lower inkers can be eliminated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 3 shows an outline view and a development view of the surface of a kneading roller for printing as one embodiment of the present invention. However, the shapes shown here are those when applied to a printing machine disclosed in Japanese Patent Laid-Open No. 2000-85095. If the shape of the kneading roller for printing of the present invention is satisfied, the shape is adapted to each printing machine. The shape of the case is not limited.

  As shown in FIG. 3, the printing kneading roller of the present invention has a predetermined distance with respect to a center line ab from one end 1a to the other 1b at both ends in the axial direction of the printing kneading roller and passing through the center of the shaft of the printing kneading roller. With the angle θ, the first groove 1 formed on the surface of the printing kneading roller and the first groove 1 in the winding direction symmetrical to the first groove 1 with respect to the center line ab passing through the center of the axis of the printing kneading roller. The second groove 2 formed from 2b to 2a so as not to intersect with the first groove 1 is processed.

Here, the groove width D and the predetermined angles θ (0 ° <θ <90 °) and θ ′ (−90 ° <θ ′ <0 °) of the first groove 1 and the second groove 2 are preferably When the first groove 1 and the second groove 2 do not intersect with each other and when the printing kneading roller and the adjacent roller are in contact with each other, there is no problem such as rattling, and smooth rotation is possible. It is obtained from the formula.
D <(φπ / 4) (1)
tan ⁻¹ (D / A) <θ <tan ⁻¹ (φπ / 2A) (2)
(More preferable ranges are 5 mm <D <50 mm, −12 ° <θ ′ <− 5 °, and 5 ° <θ <12 °.)

  Next, the action of the kneading roller for printing of the present invention formed as described above will be described by taking as an example a case where it is used for a single inker.

  In the kneading roller for printing of Example 1 in FIG. 3, when the roller length A = 790 mm and the roller diameter φ = 110 mm, Equation (1) is D <86.4 mm and Equation (2) is 1.7 ° <θ <. 12.3 °, so that this condition is satisfied, a predetermined angle θ is formed with respect to a center line ab from one end 1a to the other end 1b of the printing kneading roller in the axial direction and passing through the center of the printing kneading roller shaft. A first groove 1 formed at an angle of 8.8 ° and having a groove width D of 23 mm and a predetermined angle θ ′ with respect to the roller axial direction from one end 2b to the other end 2a of the printing kneading roller in the axial direction. With the angle of −8.8 °, the groove width D is 23 mm, and the second groove 2 is formed in a symmetrical winding direction so as not to intersect the first groove 1.

  When this shape is used for a single inker printing kneading roller f shown in FIG. 1, the ink flow is canceled by the first groove 1 and the second groove 2 as shown in FIG. The amount of transfer is made uniform.

In addition, it is also possible to use a printing kneading roller having a groove shape that is curved and intermittent, as follows, for the single inker printing kneading roller f.
As shown in FIG. 4, a predetermined angle θ is 0 ° <0 ° with respect to a center line ab from one end 1a of the printing kneading roller in the axial direction toward the intermediate point 1c and passing through the center of the shaft of the printing kneading roller. A first groove 1A having a groove width D of 23 mm and an intermediate point 1d between the printing kneading rollers and θ <90 ° and a predetermined angle θ ′ changing in a range of −90 ° <0 <0 °. The first groove 1A with respect to the groove 1B having the same shape as the first groove 1A toward the other axially 1b of the printing kneading roller and the center line ab passing through the center of the shaft of the printing kneading roller And second grooves 2A and 2B formed in a symmetrical winding direction so as not to intersect with the first groove 1B.

  Here, changing the predetermined angle θ results in a curved shape as shown in a development view (Y) of FIG. Further, although the groove is divided at the intermediate point in the axial direction, the ink transfer amount is made uniform in the range of one half on each side.

  The shape of the bottom surface of the groove was a curved surface as shown in FIG. When the square groove as shown in FIG. 6 is used, the ink is deposited on the edge portion, and if the ink is peeled off during printing, the printing density may be unstable. However, the shape shown in FIG. Occurrence can be prevented.

  Next, the operation of the kneading roller for printing of the present invention formed as described above will be described by taking as an example a case where it is used for a double inker.

  In a printing machine equipped with a double inker, the groove width of the kneading roller f ″ for printing was changed, and the density of the printed material was measured. As a result, as shown in FIG. This is the reduction rate of the surface area of the kneading roller f ″, which is hereinafter referred to as a cut rate), and the relationship between the printing density and the printing density was obtained. Here, the print density difference is obtained by subtracting the print density of the lower inker from the print density of the upper inker. As can be seen from this figure, the printing density of the upper and lower plates can be made uniform by reducing the surface area of the lower kneading roller f ″ by about 13% with respect to the upper kneading roller f ′.

  In the kneading roller for printing of Example 2, in FIG. 3, when the roller length A = 790 mm and the roller diameter φ = 110 mm, Formula (1) is D <86.4 mm, Formula (2) is 1.7 ° <θ < 12.3 °, so that this condition is satisfied, a predetermined angle θ is formed with respect to a center line ab from one end 1a to the other end 1b of the printing kneading roller in the axial direction and passing through the center of the printing kneading roller shaft. A first groove 1 formed at an angle of 8.8 ° and having a groove width D of 23 mm and a predetermined angle θ ′ with respect to the roller axial direction from one end 2b to the other end 2a of the printing kneading roller in the axial direction. Due to the angle of −8.8 °, the groove width D is 23 mm, and the second groove 2 is formed in a symmetrical winding direction so as not to intersect the first groove 1. If the kneading roller for printing f ″ having this shape is used, the surface area is reduced by about 13% with respect to the kneading roller for printing f ′. In a printing press equipped with a double inker, the ink transfer amount of the upper and lower inkers is reduced. The difference can be eliminated.

  In the shape shown in FIG. 8, the groove width of the first groove 1 and the groove width D of the second groove 2 are each equally divided into two, and the groove width (D / 2) is 11.5 mm. Even in this shape, the formulas (1) and (2) are satisfied, and the cut rate of the groove is equal to the cut rate of the shape shown in FIG. 3, so the same effect as the shape shown in FIG. 3 is obtained. It is done.

In a printing machine equipped with a double inker, the following printing kneading roller is used as the printing kneading roller f ′ of the upper inker.
In FIG. 3, when the roller length A = 790 mm and the roller diameter φ = 110 mm, the equation (1) is D <86.4 mm and the equation (2) is 1.7 ° <θ <12.3 °. A predetermined angle θ is formed at an angle of 8.8 ° with respect to a center line ab from one end 1a to the other end 1b at both ends in the axial direction of the printing kneading roller and passing through the center of the shaft of the printing kneading roller. The groove width D is determined by the first groove 1 having a diameter of 23 mm and the angle θ ′ of −8.8 ° with respect to the roller axial direction from one end 2b to the other end 2a of the printing kneading roller in the axial direction. It has a second groove 2 formed in a symmetrical winding direction so as not to intersect the first groove 1 at 23 mm.
The following printing kneading roller is used as the printing kneading roller f ″ for the lower inker. This shape reduces the surface area by about 13% from the printing kneading roller f ′.

  In a printing machine equipped with a double inker, by using the printing kneading roller f ′ and the printing kneading roller f ″, the amount of ink transferred in the roller axial direction of the upper inker and the lower inker is made uniform, and the upper and lower inkers The difference in the amount of ink transfer can be eliminated.

Ink supply device (single inker) Ink supply device (double inker) Grooving shape 1 of kneading roller for printing Grooving shape 2 of kneading roller for printing Cross-sectional view of groove processing shape of printing kneading roller 1 Cross-sectional view of groove shape of kneading roller for printing 2 Relationship between cut rate of kneading roller f '' for printing and difference in printing density between upper and lower inker Grooving shape 3 of printing kneading roller

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st groove | channel 2 2nd groove | channel i, j Gold roller a, b Plate-forming roller f Kneading roller for printing A Length of kneading roller D Groove width (theta), (theta) 'Predetermined angle

Claims (5)

A printing kneading roller provided in an ink supply unit of a printing press, wherein at least one first groove formed on a surface of the printing kneading roller is formed so as not to intersect the first groove At least one second groove, and the first groove and the second groove have predetermined angles (θ) and (θ ′) with respect to the axial direction of the printing kneading roller. A kneading roller for printing with groove processing, wherein at least one end of the first groove and the second groove is formed to both ends of the kneading roller. The predetermined angle (θ) of the first groove and the predetermined angle (θ ′) of the second groove are −90 ° <θ ′ <0 ° with respect to the axial direction of the printing kneading roller. The kneading roller for printing according to claim 1, wherein 0 ° <θ <90 °. 3. The printing kneading roller according to claim 1, wherein the first groove and the second groove are axisymmetric with respect to the roller axis, and the groove width and the number of grooves are the same. 4. The kneading roller for printing according to claim 1, wherein the bottom surfaces of the first groove and the second groove are curved surfaces. An ink supply apparatus comprising the kneading roller for printing according to any one of claims 1 to 4.

Images