JPH01165440A - Ink transfer roll oscillating control device - Google Patents

Abstract

PURPOSE:To accomplish optimal ink supply so as to improve printing quality by controlling the oscillating operation of an ink transfer roll oscillating device on the basis of a pattern area to be printed with an ink transfer roll being in contact with ink feeding and ink mixing rolls. CONSTITUTION:Printing speed is obtained from a signal sent from a near-by switch 10 for measuring the number of revolutions of a printing cylinder driving system, and the number of oscillating revolutions of an ink transfer roll 3 is controlled to remain constant. The average pattern area rate is operated for each color by means of a pattern area rate meter 16 for storing together with the printing speed in a memory table 12. Contacting time T1, T2 when the ink transfer roll 3 is allowed to come into contact with an ink feeding roll 2 and an ink mixing roll 4 are obtained from the printing speed, average pattern area rate and paper quality, ink quality tables as correcting values for the coefficient of the ink speed, and a solenoid of a four-way changeover valve 8 is ON/OFF controlled on the basis of these contacting times so obtained. The ink transfer roll 3 is oscillated at a predetermined oscillation cycle so as to accomplish optimal ink supply with the contacting time T1 and T2 when the ink transfer roll 3 is allowed to come into contact with the ink feeding roll 2 and the ink mixing roll 4, respectively, being maintained.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to an ink transfer device that swings between an ink dispenser roll and an ink mixer roll provided in an inking device of a rotary offset printing press to supply optimal ink. The present invention relates to a roll swing control device.

[Prior Art] As is well known, the ink transfer roll of an offset rotary printing press swings between the ink dispenser roll and the ink mixer roll by a driving force branched from the drive system that drives the ink roller group, etc., and supplies ink. An ink transfer device was used. For this reason, the ink roll's oscillation cycle increases in proportion to the printing speed, resulting in an excessive amount of ink being supplied to the printing plate, making it difficult to supply the optimal ink, and it is hoped that the printing quality will be improved. It was rare.

In general, if the oscillation cycle of the ink transfer roll is constant, the rotational speed of the ink ductor roll, the contact time of the ink ductor roll, and the contact ratio of the ink mixer roll are constant, the amount of ink supplied will not be optimal. Therefore, the amount of ink supplied onto the printing plate is not optimal.

In addition, the relationship between the printing speed and the swing cycle of the ink transfer roll is that the contact time between the ink transfer roll, the ink fountain roll, and the ink mixer roll is constant, and the number of swings of the ink transfer roll is proportional to the printing speed. When the amount of ink increases, the amount of ink supplied to the printing plate tends to be excessive and the printing quality tends to deteriorate.

[Problems to be solved by the invention] The present invention has been made in view of the above-mentioned conventional technology, and its purpose is to, independently of the drive system that drives the ink roller group, A drive source for swinging the ink transfer roller is provided, and by this driving force, the ink transfer roll is pivotally supported by a pair of spin farms that can swing around a fulcrum, and the ink transfer roll moves between the ink dispenser roll and the ink transfer roller. Control the contact time of the ink transfer roll to control the contact time of the ink transfer roll and use the data in the paper quality and ink quality tables as correction values based on the printing plate image area ratio for each color to be printed. The aim is to supply optimal ink and improve printing quality.

A further object of the present invention is to have the same configuration as the ink transfer roll device described above, to maintain a constant contact time between the ink transfer roll or the ink fountain roll and the ink mixer roll, and to optimize the image area ratio based on the printing speed. The aim is to improve printing quality by supplying suitable ink.

[Means for Solving the Problems] The ink transfer roll swing control device of the present invention has an ink transfer roll positioned between an ink dispenser roll and an ink mixer roll, and the ink transfer roll is connected to a pair of swing arms. Both ends are supported, the swing arm is connected by a connecting shaft, and the swinging operation of the ink fountain roll is controlled by an air cylinder connected to the swing arm and a directional switching valve that switches the operation of the air cylinder. In the ink transfer roll swinging device, a control device is provided for controlling the swinging operation of the ink transfer roll based on the pattern area to be printed while the ink transfer roll is in contact with the ink dispenser roll and the ink mixer roll, respectively.

In addition, the control device of the present invention improves the conventional technology by:
a detection pattern area ratio meter for detecting the plate cylinder rotation speed of the printing press;
The relationship between the contact time ratio of the paper quality and ink quality table with predetermined stages of paper quality and ink quality, the contact time ratio of the ink transfer roll in contact with the ink dispenser roll and the ink mixer roll, and the pattern area ratio, using the printing speed as a parameter, is expressed by a functional formula. The contact time of the ink transfer roll is determined from the memory table using the data in the paper quality and ink quality tables as correction values based on the printing speed obtained based on the rotation speed obtained from the detection means. A calculation unit that calculates the contact time and a control unit that controls ON/OFF of the solenoid of the directional switching valve via a timer based on the contact time.

Furthermore, the control device of the present invention improves upon the prior art by:
A detection means for detecting the number of rotations of the plate cylinder of the printing press during operation, and a pattern surface tI for determining the pattern area of each color by separating the pattern to be printed on printing paper into each color! [A rate meter, a function table that determines the stages of paper quality and ink quality, a memory file that stores a relational expression between printing speed and ink transfer roll oscillation cycle with the average image area ratio as a parameter, and the same detection means. The calculation unit calculates the oscillation cycle from the printing speed obtained based on the rotation speed obtained from the paper quality and ink quality table using the data in the table as a correction value, and calculates the time of 1 cycle corresponding to the same cycle. Turn on the solenoid of the directional control valve via the timer based on the cycle time.
A control section for FF control was provided.

Note that the functional expression can also be constructed as shown below.

(1) The oscillation cycle of contacting and oscillating the ink transfer roll, ink fountain roll, and ink mixer roll, respectively, is constant, and the relationship between the contact time ratio of the ink transfer roll and the average pattern area ratio is determined using the printing speed as a parameter. , a plurality of linear function equations are applied using a plurality of average picture area ratios as boundaries.

(2) Assuming that the contact time during which the ink transfer roll, ink fountain roll, and ink mixer roll contact each other and swing is constant, the relationship between the printing speed and the swing cycle of the ink transfer roll is calculated using the average pattern area ratio as a parameter. , multiple linear function equations are applied with multiple printing speeds as boundaries.

The control device is preferably a control device with a built-in computer.

[For production] The printing speed is determined from the rotation signal of the plate cylinder drive system detection means.

Next, the oscillation cycle of the ink transfer roll is controlled to a constant level,
The pattern area ratio is calculated for each color by calculating the pattern area ratio and stored in a memory table together with the printing speed. Furthermore, the functional expression of the image area and contact time ratio, the coefficient b (9) representing the paper quality and the ink quality, and the contact time of the ink transfer roll, ink fountain roll, and ink mixing roll are determined, and the directional control valve is controlled via a timer. Controls the solenoid ON/OFF.

This control signal controls the directional valve to supply the compressed air supplied from the pneumatic source to the piston or rod side of the air cylinder, and determines the time of contact with the ink transfer roll or the ink ductor roll and the ink mixer roll. It is possible to supply the optimum amount of ink by swinging in a predetermined operating cycle while maintaining contact time with the ink.

Further, another aspect of the invention is as follows. The contact time of the ink transfer roll is kept constant and the swing cycle of the ink transfer roll is controlled.

That is, a signal that detects the number of plate cylinder rotations is converted into a printing speed and stored in a memory table. In this memory table, the relationship between the printing speed and the swing cycle of the ink transfer roll wheel is stored using pattern side 1 as a parameter.
Memorizes function formulas.

The functional formula stores the picture area ratio as a coefficient. Based on this functional formula, find the oscillation cycle of the ink transfer roll,
The oscillating operation of the ink transfer roll is controlled by roughly determining the time of one cycle corresponding to the oscillating cycle and controlling the solenoid of the directional control valve ON10 FF through the timer based on the time of the same cycle. The optimum amount of ink was then supplied from the ink dispenser roll to the ink mixer roll.

Hereinafter, embodiments of the present invention will be described in detail with reference to one drawing. Note that a microcomputer is used as the control device.

[First Example] In this example, the oscillation cycle of the ink transfer roll is constant,
This is an example of controlling the contact time of the ink transfer roll.

FIG. 1 shows a schematic diagram of a swinging device and a swinging control device for an ink transfer roll in a rotary offset printing press;
The figure shows a perspective view of the swinging device for the ink transfer roll.

In both figures, the ink in the ink fountain 1 is in contact with the ink ductor roll 2, and the ink on the outer periphery of the rotating ink ductor roll 2 is transferred to the rotating ink mixing roll 4 via the swingable ink transfer roll 3. It is configured to transfer.

The ink transfer roll 3 is pivotally supported by a pair of swing arms 6 that are swingably supported by a connecting shaft 5, and the lower end of the swing arms 6 is engaged with an end of a rod 7a of an air cylinder tough.

The piston side and rod side of this cylinder tough are connected to an air pressure source via a four-way switching valve 8. The rotational speed of the plate cylinder drive system is detected by the proximity switch IO, inputted to the control device 11, and stored.

As shown in FIG. 3, the memory table 12 stores an optimal function table 12a, a function equation table 12b, a coefficient b table 12e, and a paper quality and ink quality table 12c. The contact time of the ink transfer roll 3 when the printing speed is set as a parameter and the oscillation cycle is constant is determined by =bS in the function formula in the function formula table 12b and data b+, bi, bi of the coefficient b chifur 12e. It is determined. That is, in the above relational expression, =bS is the contact time ratio K (however) as shown in FIG.

T is the time that the ink transfer roll 3 is in contact with the ink dispenser roll 2, and T2 is the average picture area that is the average of the time that the ink transfer roll 3 is in contact with the ink mixing roll 4 and the picture area ratio measured by the picture area ratio meter 16. The relationship between ratio (%) S is shown. Coefficients bl, b2 . in the coefficient b table 12e. b...
is a constant determined by printing speed.

The contact time ratio K (%) and the average picture area ratio S (%) are ratios when the printing press capacity is 100%. paper quality,
The ink quality table 12C includes correction values C+ and C2 for correcting the coefficient b (coefficient determined by the plate cylinder rotation speed) of =bS in the above relational expression.

C3 is memorized. A timer 13 controls the contact time T, , T, during which the ink transfer roll contacts the roll. 14 performs calculation processing necessary for controlling the ink transfer roll.

15 is a control unit that processes control signals for the ink transfer roll 3; Reference numeral 16 denotes a pattern area ratio meter, which separates the pattern to be printed on printing paper into each color and calculates the pattern area ratio of each color.

Note that the rotational speed of the ink ductor roll 2 is assumed to increase in proportion to the printing speed, and is within a range where the ink transfer roll 3 can come into contact with the ink film of the ink ductor roll.

Note that the paper quality and ink quality table 12C includes newspaper,
The rank of paper quality determined by coated paper, art paper, etc.
Ink color, e.g. red, blue.

It stores data that is converted into coefficients based on a combination of ranks based on physical properties such as yellow.

This data has been converted into a coefficient at the same level as the coefficient S, and is used as a value for correcting the coefficient of =bS in the function equation.

Next, the swinging operation of the ink transfer roll of the first embodiment will be described.

The printing speed is determined from a signal from a proximity switch 10 that measures the rotational speed of the plate cylinder drive system. Next, the number of rotations of the ink transfer roll 3 is controlled to be constant, and the image area ratio for each color is calculated using the image area ratio meter, and the average image area ratio is calculated in the calculation section, and is stored together with the printing speed in the memory table. . Furthermore, the function formula (
4) and a printing speed coefficient b table 12e. Then, there is a paper quality and ink quality table 12 as correction values for printing speed, average picture area ratio, and the coefficients.
The contact time T, , T, during which the ink transfer roll 3 contacts the ink ductor roll 2 and the ink mixer roll 4 is calculated from c. Then, based on this contact time T I and T 2,
The solenoid of the four-way switching valve 8 is turned to O via the timer 13.
N/OFF control.

This control signal controls the four-way switching valve 8 to supply compressed air from the pneumatic source to the piston side or rod side of the air cylinder tuff, so that the ink transfer roll 3 comes into contact with the ink fountain roll 2. While maintaining the contact time T and the contact time T2 with the ink mixing roll 4, the ink can be oscillated in a predetermined oscillation cycle to supply the optimum ink.

[Second Example] In this example, the same ink transfer roll device as in the first example is used, the contact time of the ink transfer roll 3 is kept constant,
A control device 11 is used to control the swing cycle of the ink transfer roll.

In FIG. 1, reference numeral 10 denotes a proximity switch that detects the number of rotations of the plate cylinder of the printing press during operation, and the signal detected by the proximity switch IO is processed into a printing speed V in the control device 11 and recorded in the memory table 12. be attacked. In this memory table 12, as shown in FIG. Formula N=
aV is stored in the optimum amount formula table 12b.

The printing speed (%) and swing cycle (%) are expressed as a ratio when the maximum printing speed V of the printing press and the upper limit of the capacity of the swing cycle N are set to 100%. The above functional formula N
= The coefficient a of aV is a l + a Q + a 3...
* is selected from the coefficient a table 12d, and the swing cycle N of the ink transfer roll is determined from the printing speed V and the coefficient a.

3. The paper quality and ink quality table 12c is newspaper,
The rank of paper quality determined by coated paper, art paper, etc.
Stored is data that is converted into coefficients based on combinations of ranks based on physical properties of ink colors, such as red, blue, and yellow.

This data has been converted into a coefficient at the same level as the coefficient a, and is used as a value for correcting the coefficient a of the function equation N=aV.

Next, the swinging operation of the ink transfer roll of the second embodiment will be described.

First, the printing speed V is determined from the signal of the proximity switch IO. Then, the timer 13 is set so that the contact times T, , T, between the ink transfer roll 3 and the ink mixing roll 4 are constant. Furthermore, the pattern area ratio of the printing plate for each color is measured using a pattern area ratio meter 16. The same pattern area rate is obtained by calculating the average pattern area rate S using the calculation unit 14, and then using the relationship between the plate cylinder printing speed V and the average pattern area rate S, the ink transfer oscillation cycle N (
%). The time of one cycle corresponding to the swing cycle is determined from this swing cycle, and the solenoid of the directional control valve 7 is controlled to turn ON/OFF via the timer 13 and the control unit 15 based on the time of the cycle. The swinging motion of the ink transfer roll 3 is controlled to supply optimal ink from the ink dispenser roll 2 to the ink mixing roll 4.

[Third Embodiment] This embodiment is the same as the first embodiment in that the swing control of the ink transfer roll is performed using the ink roll device and the ink roll swing control device.

In this embodiment, the oscillation cycle of the ink transfer roll is kept constant, the contact times T, , T2 are changed, and a plurality of =BSs are combined to perform optimal control of the ink.

That is, as shown in FIG. 6, with a plurality of average picture area ratios Sl and S2 as boundaries, the −th order function is expressed as =Br St ,
Apply 3 = B3 S3 to Kz = B2 S2,
A relationship is formed between the average picture area ratio S and the contact time ratio. Then, by adding the correction coefficient in the 1 paper quality 2 ink table 12C to the above coefficient,
r, 2=B2°SR, and 3=B3°S:l, and the contact time between the ink transfer roll or ink ductor roll 2 and the ink mixing roll 4 was controlled.

[Fourth Embodiment] This embodiment is the same as the second embodiment in that the swing control of the ink transfer roll is performed using the ink roll device and the ink roll swing control device.

In this example, the contact time T r of the two ink transfer rolls,
Optimum control of the ink is performed by keeping T* constant, changing the same oscillation cycle N, and combining a plurality of -order intervals N=AV.

That is, as shown in FIG. 7, multiple printing speeds (%)
With Vl and Vl as boundaries, -order function N, = A, V, , N2
=A2V2, N3 =A3V, to form a relationship between the swing cycle N and the printing speed V. Then, the correction coefficients C+, C2, in the paper quality and ink quality table 12c,
Adding C3 to the above coefficient, the above - order number 2N□' = A
+"V 1', N 2'=A2'V, °, N i
' = A : s' V : l' and correct it as ink transfer roll 3 or ink discharge roll 2 and ink mixing roll 4.
The contact time can now be controlled.

In all of the above-mentioned Examples 1, 2, and 3.4, the ink fountain roll 2 is connected to the plate cylinder drive system so that the number of revolutions increases slightly in proportion to the printing speed. Furthermore, in the case of a double-sided printing machine in which inking devices are installed above and below within the same printing unit during double-sided printing, if the swing cycle of the ink transfer roll 3 is the same, an impact force is simultaneously applied to the plate cylinder of the printing unit. In addition, both plate cylinders may resonate and cause tabling.

Therefore, by applying the same pattern with a delay time added to the contact time pattern, a phase difference is given to the oscillation cycle of the ink transfer roll 3, the vibration is alleviated, and printing quality is thereby improved. There is.

[Effects of the Invention] As described above, according to the present invention, a drive source is provided independently of the drive system that drives the ink roller group, and this drive force makes it possible to swing around the fulcrum. By swinging the ink dispenser roll and the ink roll of the ink transfer roll which are pivotally supported by a pair of swinging arms, the optimum amount of ink can be supplied from the ink dispenser roll to the ink picker roll, resulting in high printing quality. can be improved.

Similarly, in the present invention, the ink transfer roll or the ink fountain roll and the ink mixer roll are brought into contact with each other at an optimal oscillation cycle to supply optimal ink, thereby improving printing quality.

[Brief explanation of the drawing]

FIG. 1 shows a swinging device and a swinging control device for an ink transfer roll of a rotary offset printing press. FIG. 2 is a perspective view showing the swinging device of the ink transfer roll, FIG. 3 is a diagram showing details of the memory table 12 in FIG. 1,
Figures 4 and 6 are diagrams showing the relationship between average pattern area ratio S and contact time ratio, and Figures 5 and 7 are diagrams showing the relationship between printing speed (%) and ink transfer roll oscillation cycle N. .

Claims (6)

[Claims] (1) An ink transfer roll is located between the ink dispenser roll and the ink mixer roll, and the ink transfer roll is supported at both ends by a pair of swing arms, and the swing arms are connected by a connecting shaft, and the ink transfer roll is connected to the swing arms. In the ink transfer roll swing device, the ink transfer roll swinging device is configured to control the swinging operation of the ink dispenser roll by an air cylinder and a directional switching valve that switches the operation of the air cylinder.
An ink transfer roll, characterized in that it is provided with a control device that controls the swinging operation of the ink transfer roll based on the picture area of the printing plate to be printed while the ink transfer roll is in contact with the ink fountain roll and the ink mixing roll, respectively. Swing control device. (2) The control device includes a detection means for detecting the rotation speed of the plate cylinder drive system of the printing press, and calculates the pattern area ratio of each color by separating the pattern on the printing plate to be printed on printing paper into each color. Image area ratio meter, paper quality with predetermined stages of paper quality and ink quality,
An ink quality table, a memory table storing a functional formula for the relationship between the contact time ratio of the ink transfer roll in contact with the ink dispenser roll and the ink mixer roll and the average pattern area ratio using the printing speed as a parameter, and the detection means. a calculation unit that calculates the contact time of the ink transfer roll from the memory table using the data in the paper quality and ink quality tables as correction values based on the rotation speed determined by the rotation speed; and a direction switching unit that uses a timer based on the contact time. Turn the valve solenoid to O
2. The ink transfer roll swing control device according to claim 1, further comprising a control section that performs N/OFF control. (3) The control device includes a detection means for detecting the number of revolutions of the plate cylinder drive system of the printing press during operation, and a pattern for each color obtained by separating the pattern on the printing plate to be printed on printing paper into each color. A pattern area ratio meter for calculating the area ratio, a function table that determines the stages of paper quality and ink quality, and a memory table that stores the relational expression between printing speed and ink transfer roll oscillation cycle with the average pattern area ratio as a parameter; a calculation unit that calculates an oscillation cycle based on the rotational speed obtained from the detection means, using the printing speed, paper quality, and data in the ink quality table as correction values, and calculates the time of one cycle corresponding to the oscillation cycle; and,
2. The ink transfer roll swing control device according to claim 1, further comprising a control unit that controls ON/OFF of a solenoid of the directional control valve via a timer based on the time of one cycle. (4) The oscillation cycle in which the ink transfer roll contacts and oscillates with the ink dispenser roll and the ink mixer roll is constant, and the relationship between the contact time ratio of the ink transfer roll and the average pattern area ratio is determined using the printing speed as a parameter. 3. The ink transfer roll swing control device according to claim 2, wherein a plurality of linear function equations are applied with a plurality of average pattern area ratios as boundaries. (5) Assuming that the contact time during which the ink transfer roll contacts and oscillates with the ink dispenser roll and the ink mixer roll is constant, the relationship between the printing speed and the ink transfer roll oscillation cycle is expressed using the average pattern area ratio as a parameter; 4. The ink transfer roll swing control device according to claim 3, wherein a plurality of linear function equations are applied at a plurality of printing speeds. (6) The ink transfer roll swing control device as set forth in claims 1, 2, 3, 4, and 5, wherein the control device is a computer.