JPH1170639A - Register control method and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct and control longitudinal misregistration and twist misregistration at the same time. SOLUTION: A register control apparatus for moving a compensator roll arranged between an objective printing unit and the printing unit of the front stage thereof to adjust the length of a web includes a sensor detecting the misregistrations on both sides of in the lateral direction of the web on the discharge side of the objective printing unit, first and second automatic aligning bearing parts 30A, 30B supporting the rotary shaft of a compensator roll 22 in an arbitrary direction in a rotatable manner on both sides of an axial direction, first and second motors 36A, 36B for moving the bearing parts 30A, 30B respectively independently and a register control part for moving the compensator roll 22 to a position respectively eliminating misregistrations on both sides of the axial direction of the web detected by the sensor by the motors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a register control method and apparatus, and more particularly to a register control method and apparatus suitable for multicolor printing on a web made of paper or plastic film.

[0002]

2. Description of the Related Art In the case of so-called multicolor printing of two or more colors on a web made of paper, plastic film, or the like that is continuously conveyed, a picture of each color is printed at a correct position, and a shift between pictures in each color, That is, it goes without saying that the absence of misregistration is important for the quality of printed matter.

[0003] Generally, as shown in FIG. 4, two color patterns P and P 'are conceptually shown in FIG.
A vertical misregistration A deviating in the flow direction of the web W (vertical direction in the figure), a lateral misregistration B deviating in a direction perpendicular to the flow direction, and a direction in which the pictures P and P 'rotate as shown in FIG. There is a torsional misregistration C.

[0004] The registration of multicolor printing refers to matching the printing position of a basic color (basic color) with the printing position of another color (control color). The expression that the basic color is the first color and the color to be controlled is the second color is mainly used.

[0005] When the above-mentioned misregistration occurs between the first color and the second color, a method of correcting the misregistration is to use a compensator roll for the vertical register to use a pattern between the two colors, that is, a pattern of each color. In general, a method of correcting the length (path length) of the web W between the plate cylinders for printing the image is performed by moving the plate cylinder in the axial direction to correct the lateral registration.

Now, the details of the method of correcting the horizontal register will be omitted, but the method of correcting the vertical register will be described below in detail with reference to FIG. FIG. 6 shows a first printing unit 10 for printing the first color and a second printing unit 10 for the second color located downstream thereof.
1 shows a printing unit 12.

The web W passes between the plate cylinder 14 and the impression cylinder 16 constituting the first printing unit 10, and after the first color is printed, the web W is printed on the plate cylinder 18 and the impression cylinder 20 of the second printing unit 12.
, The second color is printed, and then conveyed in the direction of the arrow to move to the next step.

If there is a vertical misregistration between the printing of the first color and the printing of the second color by the first and second printing units 10, 12, the printing unit is disposed between the two units. The vertical registration error is corrected by moving the compensator roll 22 in the direction of the arrow and adjusting the path length between the two.

FIG. 7 shows the twist register shown in FIG.
As shown in an enlarged view of the second printing unit 12 viewed from an oblique direction, a so-called twist roll 24, which is a kind of guide roll, disposed on the entrance side of the second printing unit 12, is shown in FIG.
The correction is performed by moving one or both sides in the axial direction and moving the web W to the position 24 'shown by the broken line, and changing the path length in the width direction to the state of W' shown by the broken line. be able to.

However, since the twisting roll 24 is a kind of guide roll as described above, it does not have a function of automatically adjusting its position, and is adapted to the characteristics of the web W used by the operator before starting work or during printing. It is merely manually adjusting the position in advance.

For the above vertical register and horizontal register, register correction is generally performed automatically. Specifically, a registration mark called a register mark is printed on the web at a position that does not interfere with the print pattern, and the mark is placed online on the target printing unit side including the entrance and exit sides of the target printing unit. It is widely practiced to perform feedback control so that the misregistration becomes zero while detecting the error.

[0012] For example, regarding the register in the vertical direction of the web, a register mark printed in a second color to be controlled,
Register marks printed in the first color that should be the basis,
For example, the output side of the second printing unit 12 shown in FIG.
That is, detection is performed on the downstream side of the plate cylinder 18, a vertical misregistration is calculated from the distance between the two marks, and the path length between the printing units is changed by the compensator roll 22 so that the misregistration becomes zero. For lateral displacement, control is performed to calculate lateral misregistration from a similarly detected register mark, and to correct the misregistration by moving the plate cylinder in the axial direction so that it becomes zero.

[0013] In addition, since the register shift in the twisting direction cannot be usually detected when the register mark is on only one side of the web, the register shift is performed by, for example, printing the register mark on both side edges in the width direction of the web. It is assumed that the misregistration in the direction can be detected, but automatic control of the misregistration in the torsional direction is also conceivable.

[0014]

However, in order to automatically control the misregistration in the twisting direction by using the twisting roll 24, the twisting roll 24 generally has no automatic position adjustment function as described above. Therefore, there is a problem that an automatic adjustment mechanism for driving the roll 24 in the twisting direction must be added, and in this case, there is a problem that the cost is increased.

Even if an automatic adjusting mechanism can be added to the twisting roll 24, it is difficult to individually control the twisting register and the vertical register, and if the twisting register 24 corrects the twist register deviation, There is also a problem that it is difficult to appropriately control both at the same time because it affects the register in the vertical direction.

Further, when the automatic adjusting mechanism is installed on the twisting roll as described above, the twisting roll 24 is usually disposed immediately before the printing press, that is, the plate cylinder, so that the work space for the operator is reduced. However, there is also a problem that the work becomes difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and provides a register control method and apparatus capable of simultaneously correcting a vertical register shift and a twist register shift without reducing an operator's working space. The task is to provide.

[0018]

SUMMARY OF THE INVENTION According to the present invention, when printing is performed sequentially on two or more printing units on a continuously conveyed web, the target printing is performed based on the amount of misregistration detected on the target printing unit side. In a register control method for moving a compensator roll disposed between a unit and a preceding printing unit and adjusting a web length between the two printing units, the target printing unit side includes a web in both sides in the width direction of the web. The above problem has been solved by detecting the misregistration occurring in each of the above, and by independently moving the compensator rolls on both sides in the axial direction to positions where the detected misregistration is eliminated.

According to the present invention, when printing is performed sequentially on two or more printing units on a continuously conveyed web, the target printing unit and its preceding stage are determined based on the amount of misregistration detected on the target printing unit side. In the register control method for moving the compensator roll disposed between the printing units and adjusting the length of the web between the printing units, the target printing unit side is formed on both sides in the width direction of the web. A control means for detecting the misregistration, and independently moving the compensator rolls on both sides in the axial direction at positions where the detected misregistration is eliminated. It is.

In the present invention, a drive mechanism for supporting the rotating shaft of a compensator roll used for longitudinal register control by an automatic centering bearing portion rotatable in the front-rear and left-right directions and adjusting the position of the compensator roll. Are installed independently on both sides in the axial direction, so even if different vertical misregistrations occur on both sides in the width direction of the web, each misregistration amount is independently applied to the compensator roll drive units on both sides in the axial direction. It is possible to provide feedback,
Using the compensator roll, it is possible to perform automatic control for simultaneously correcting the misregistration in the vertical direction and the twist direction.

In the present invention, the target printing unit side is, as described above, a predetermined range including the entrance side and the exit side of the printing unit to be controlled, in the vicinity of the unit where the register mark can be detected. I do.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic perspective view showing a main part of a register control device according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a compensator roll of the register control device and a driving device thereof. It is a schematic front view.

The register control apparatus of the present embodiment controls the second printing unit 12 which is substantially the same as that shown in FIG.
A vertical register control compensator roll 22 disposed upstream of a guide roll 26 (corresponding to the twist roll 24) on the entry side of the printing unit 12;
On the output side of the printing unit 12, a pair of sensors (detection means) 28 for respectively detecting misregistration on both sides in the width direction of the web W are provided.

As shown in FIG. 2, the register control device according to the present embodiment is arranged such that the rotation axis of the compensator roll 22 is
The first and second self-aligning bearing portions 30A rotatably supported in arbitrary directions on both sides in the axial direction shown as A side and B side in the drawing,
30B.

Further, the register control device includes the first and second registers.
As a drive mechanism (means) for independently moving the self-aligning bearing portions 30A and 30B, the two bearing portions 30A and 30B
First and second brackets 32 to which B is respectively fixed
A, 32B and first and second ball screws 34A, 34B screwed to the brackets 32A, 32B, respectively.
And the first and second motors 36A, 36A that respectively move the first and second self-aligning bearing portions 30A, 30B independently by rotating the ball screws 34A, 34B.
B.

The register control device moves the first and second self-aligning bearing portions 30A and 30B by the first and second motors 36A and 36B, and the signals are detected by the pair of sensors 28. A register control unit (control means, not shown) for controlling the movement of the compensator roll 24 to a position for eliminating the register shift on both sides in the width direction of the web W.
And

That is, the compensator roll 22 comprises:
The first and second self-aligning bearing portions 30A and 30B are rotatably supported on both axial sides corresponding to the torsion direction,
The first and second brackets 32A, 32B supporting the bearing portions 30A, 30B can be independently changed in position on both axial sides by motors 36A, 36B via ball screws 34A, 34B.

Although not shown, the bearing 30A,
At least one of the bracket 30B and the brackets 32A, 32B is provided with a mechanism that is slidable in the axial direction of the compensator roll 22, whereby the rotation axis of the compensator roll 22 is not necessarily in the flow direction of the web W, that is, the vertical arrow in the figure. The first and second motors 36 for feeding the compensator roll 22 are rotatable even if they are not perpendicular to the stroke direction of the roll shown in FIG.
A and 36B can be independently driven.

Therefore, the first and second printing units 1 shown in FIG.
0, 12, the register marks M1, M2 printed on both sides of the web W in the width direction, that is, the shift between M1A and M2A on the right side in FIG. When a misregistration is detected on the B side, control can be performed to appropriately correct the path lengths on both sides in the width direction of the web W according to the amount of the misregistration.

That is, the second printing unit 12 shown in FIG.
When a misregistration occurs between a picture (not shown) printed by the first printing unit (not shown in the figure) located immediately before and a picture printed by the plate cylinder 18 of the second printing unit 12. , The misregistration between the two colors is the registration mark M
1, M2 can be detected by reading online with a pair of sensors 28 in the width direction, and correction while printing can be performed through a register control unit (not shown).

For the sake of convenience, the explanation will be made by omitting the lateral register. If only the register misalignment in the vertical direction occurs from the register marks M1 and M2 detected by the sensor 28, the compensator roll 22 is moved in parallel to the web W. , Vertical register adjustment length D
The movement can be corrected by changing the path length at the same rate in the width direction of the web W by moving it in parallel to the position indicated by the solid line indicated by reference numeral 22A.

On the other hand, if there is a difference in the vertical misregistration on both sides from the register marks detected on both sides in the width direction of the web W in addition to the above-mentioned misregistration, the misregistration is caused in the twist direction. The compensator roll 22 is recognized as a deviation, and the compensator roll 22 is further moved on one side thereof by the twist register adjustment length E, and corrected to the position indicated by the broken line 22B.

As described above, according to the present embodiment, the vertical register on both sides in the width direction of the web W can be controlled independently, so that the vertical register and the twist register can be simultaneously corrected. Become.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, in the above embodiment, in order to measure the misregistration on both sides in the width direction of the web, the first color and the second color are used.
The registration mark is printed for each color, that is, the so-called two-mark method has been described. However, the registration mark of the first color, which is used when the registration mark of the second color cannot be used for some reason, is detected by a sensor at a predetermined position. The so-called one-mark method of measuring the misregistration from the difference between the actually measured phase and the target phase of the second color plate cylinder at the point of time may be applied to the present invention. In the case of this one mark method,
Detecting misregistration on the entrance side of the target printing unit is also performed.

In the above embodiment, the longitudinal register marks are printed on both sides in the width direction of the web, and the motor is controlled using the detection results to feed the bearings of the compensator rolls on the corresponding side independently. Although the case has been shown, the register marks are not necessarily limited to those printed on both side edges of the web, but may be printed on an appropriate empty area. Further, the register mark itself may be, for example, a so-called triangular mark, instead of the so-called register mark shown in the embodiment.

One or more marks capable of simultaneously detecting the vertical register and the twist register are printed on one side of the web, and the detection result is converted into the vertical register shift on both sides of the web, and the motor is used by using the conversion result. You may make it control.

[0039]

As described above, according to the present invention,
The vertical misregistration and the twist misregistration can be corrected simultaneously. Therefore, it is possible to reduce the misregistration defect that occurs during printing and improve the productivity.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a main part of a register control device according to an embodiment of the present invention.

FIG. 2 is a schematic front view showing a driving mechanism of a compensator roll.

FIG. 3 is an explanatory diagram showing an example of a register mark printed on both sides of a web.

FIG. 4 is an explanatory view conceptually showing each misregistration in a vertical direction and a horizontal direction.

FIG. 5 is an explanatory view conceptually showing a misregistration in a twisting direction.

FIG. 6 is an explanatory diagram showing a general vertical register control method.

FIG. 7 is a schematic perspective view showing a method of correcting a twist register shift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... 1st printing unit 12 ... 2nd printing unit 14, 18 ... Plate cylinder 16, 20 ... Impression cylinder 22 ... Compensator roll 24 ... Twist roll 26 ... Guide roll 28 ... Sensor 30A, 30B ... 1st, 1st automatic adjustment Core bearing portions 32A, 32B: first and second brackets 34A, 34B: first and second ball screws 36A, 36B: first and second motors

Claims (3)

[Claims] When printing is sequentially performed on two or more printing units on a continuously conveyed web, the target printing unit and a preceding printing unit are determined based on the amount of misregistration detected on the target printing unit side. In the register control method of moving the compensator roll disposed between the two printing units and adjusting the length of the web between the two printing units, the target printing unit side is provided with a register shift generated on both sides in the width direction of the web. A register control method, comprising: detecting and moving the compensator roll independently on both sides in the axial direction to a position where the detected register shift is eliminated. 2. The method according to claim 1, wherein when printing is performed sequentially on two or more printing units on the continuously conveyed web, the target printing unit and a preceding printing unit are determined based on the amount of misregistration detected on the target printing unit side. A register control device that moves a compensator roll disposed between the two printing units and adjusts a web length between the two printing units, wherein a detection unit that detects a register shift on both sides in a width direction of the web on a target printing unit side; A first and a second self-aligning bearing portions for rotatably supporting the rotating shaft of the compensator roll in arbitrary directions on both sides in the axial direction; and independently moving the first and the second self-aligning bearing portions. A driving means for causing the first and second self-aligning bearings to move by the driving means so as to eliminate the misalignment on both sides in the width direction of the web detected by the detecting means. And a control means for moving the compensator roll. 3. The bracket according to claim 2, wherein said driving means is respectively threaded through first and second brackets to which said first and second self-aligning bearing portions are fixed, respectively. A register control device comprising: first and second ball screws; and first and second motors for respectively rotating the two ball screws.