JP4949726B2 - Printing machine and ink supply method for printing machine - Google Patents

Description

  The present invention relates to a printing press and an ink supply method for the printing press.

In printing factories, suppressing the waste paper generated during printing has become an important issue that leads to a reduction in cost and waste of resources.
There are various types of damaged paper generated during printing, but the percentage of lost paper generated during printing is particularly large.
The cause of paper loss at the time of printing is mainly supply of an inappropriate amount of ink to the printing paper surface. For example, if the ink supply amount is excessive, stains and show-through of the printing paper surface are induced, and if the ink supply amount is insufficient, characters and patterns are lost or drowned.

Therefore, in the printing press, when printing is performed by cleaning the ink roller, since there is no ink in the ink roller group, a required ink film thickness is formed on the ink roller group of the ink supply device before printing. I am doing so. This is called pre-inking work.
In this preliminary ink winding operation, for example, as shown in Patent Document 1, each ink key is set to an opening degree corresponding to the image area ratio of the printing plate in the corresponding portion, and ink is supplied at that setting. There is.
However, this method cannot clearly grasp the total ink supply amount, and therefore cannot grasp the ink film thickness in the ink roller group in which the ink is kneaded before the cylinder is put to have substantially the same film thickness.
For this reason, the ink supply amount at the time of printing tends to be excessive supply or insufficient supply.

In order to solve this problem, there is one in which all the ink keys are supplied to the ink roller group at a constant opening regardless of the image area ratio of the printing plate.
In this case, since it is easy to grasp the ink supply amount, a situation where the ink supply amount is excessively large or insufficient is not reached.
After a predetermined amount of ink is supplied to the ink roller group in this way, each ink key is set to an opening corresponding to the image area ratio of the printing plate in the corresponding portion, and the ink roller group is rotated by the rotation of the ink source roller. To be supplied.

Japanese Patent Laid-Open No. 10-16193

However, in these conventional products, since the rotation speed of the ink base roller is slower than that of the ink roller group, the ink supplied in the width direction distribution according to the image area ratio of the printing plate is supplied to the ink roller group. The time is late. For this reason, there has been a problem in that it takes time to stabilize the printing density due to fluctuations in the ink supply.
In addition, since the cylinder is removed before the printing operation is completed, the ink is not supplied to the printing paper in the ink supply state. For this reason, since excessive ink is accumulated in the ink roller group, when printing is performed without cleaning the ink roller after the printing operation is completed, excessive ink circulation may occur when the ink roller group is initially driven. The ink film thickness at the ink form roller is increased. If the printing operation is performed in this state, the ink will be excessive, so that the surface of the printing paper may be soiled in some cases, and it will take time to stabilize the printing density due to the ink density not falling easily. There was a problem.

In view of the above problems, the present invention is capable of accurately supplying ink at the time of printing and stabilizing the printing density at an early stage, thereby reducing the amount of paper loss at the time of printing and the ink thereof. An object is to provide a supply method.

In order to solve the above problems, the present invention employs the following means.
That is, the printing press according to the present invention is attached to the surface of the plate cylinder via an ink roller group including an ink delivery roller operated in conjunction with a machine speed from an ink fountain having a plurality of ink keys and an ink base roller. An ink supply device for supplying ink to the printing plate, and at least when a predetermined operating speed is reached, and after the first predetermined time has elapsed, the operation of the ink base roller is started, and An ink supply control unit that controls ink supply, and the control unit is configured to start from the cylinder case when printing is performed without cleaning the ink roller after the printing operation is completed. A continuous printing ink supply start mode in which a second predetermined time until the start of operation of the ink source roller is set longer than the first predetermined time is provided.

According to the present invention, after printing is completed, when printing is performed without cleaning the ink roller (hereinafter also referred to as continuous printing), excessive ink is retained in the ink roller group. Ink supply is started in the ink supply start mode.
According to the continuous printing ink supply mode, the second predetermined time from the cylinder loading to the start of the operation of the ink base roller is set longer than the first predetermined time. Ink will be supplied.
If more ink is supplied to the printing plate from the ink roller group, the ink film thickness distribution and ink amount in the ink roller group at the start of operation of the ink source roller will be in good condition, so the printing density will be reduced. It can be stabilized early.
Thereby, the amount of paper loss at the time of printing can be reduced.

  Further, the printing press according to the present invention has an initial printing ink supply start mode including an ink winding process in which a plurality of ink keys are set to a substantially constant predetermined opening and a predetermined amount of ink film thickness is formed in the ink roller group in advance. Furthermore, it is provided.

According to the present invention, when printing with ink roller cleaning (hereinafter also referred to as initial printing), ink is not held in the ink roller group, so that the cylinder is removed (the ink supply device does not contact the plate cylinder). ) State, ink supply is started in the first printing ink supply start mode.
Since ink is not held in the ink roller group, first, the ink key is set to a substantially constant opening degree by the ink winding process, the ink source roller and the ink roller group are driven for a predetermined time, and a predetermined amount is applied to the ink roller group. Supply ink. Since the supplied ink is not supplied from the ink roller group to the printing plate, an ink film having a substantially constant predetermined film thickness is formed on the rotating ink roller group.
Thus, since the ink key is set to a substantially constant predetermined opening, the amount of ink to be supplied can be set strictly. For this reason, it is possible to prevent the ink supplied to the printing plate from becoming excessive or insufficient.
Next, when the opening of a plurality of ink keys is set according to the pattern of the printing plate in the corresponding part, and the ink supply roller is driven to rotate for a predetermined time by the early supply process, for example, the ink according to the set opening The ink film whose film thickness fluctuates in the width direction of the original roller reaches the engagement point with the ink delivery roller.
When the cylinder is placed in this state, the ink in the ink roller group is supplied to the printing plate, and the ink film thickness of the ink roller group gradually becomes thinner toward the plate cylinder side. When the operation of the ink fountain roller is started after the passage of the first predetermined time after the cylinder is placed, the ink film thickness set according to the pattern of the printing plate is located at the engagement point with the ink delivery roller, It will be supplied to the delivery roller.
As described above, when the operation of the ink source roller is started, the ink film thickness set according to the pattern of the printing plate is immediately supplied to the ink delivery roller, so that the printing density can be stabilized at an early stage.
Thereby, the amount of paper loss at the time of printing can be reduced.

  Further, in the printing press according to the present invention, the ink wrapping step is performed when the ink priming roller is stopped after a predetermined time has elapsed, the ink key is closed, and the ink key is closed. And a step of rotating for a predetermined time.

Further, in the printing press according to the present invention, the initial printing ink supply start mode is configured such that the ink base roller is driven to rotate for a predetermined time by an ink key opening set corresponding to the pattern of the printing plate before the cylinder insertion. And an early supply process, and the early supply process is performed following the ink winding process.
According to the present invention, when initial printing is performed, ink roller cleaning is performed, and ink is not held in the ink roller group, so that the ink winding is performed in a state of cylinder removal (the ink supply device does not contact the plate cylinder). Perform the process.
Since ink is not held in the ink roller group, first, the ink key is set to a substantially constant predetermined opening, the ink source roller and the ink roller group are driven for a predetermined time, and a predetermined amount of ink is supplied to the ink roller group. . Since the supplied ink is not supplied from the ink roller group to the printing plate, an ink film having a substantially constant predetermined film thickness is formed on the rotating ink roller group.
Thus, since the ink key is set to a substantially constant predetermined opening, the amount of ink to be supplied can be set strictly. For this reason, it is possible to prevent the ink supplied to the printing plate from becoming excessive or insufficient.
Next, an early supply process is performed. That is, when the opening of a plurality of ink keys is set according to the pattern of the printing plate in the corresponding part and the ink fountain roller is driven to rotate for a predetermined time, for example, the width direction of the ink fountain roller according to the set opening Thus, the ink film whose film thickness fluctuates at the end reaches the point of engagement with the ink delivery roller.
When the cylinder is placed in this state, the ink in the ink roller group is supplied to the printing plate, and the ink film thickness of the ink roller group gradually becomes thinner toward the plate cylinder side. When the operation of the ink fountain roller is started after the passage of the first predetermined time after the cylinder is placed, the ink film thickness set according to the pattern of the printing plate is located at the engagement point with the ink delivery roller, It will be supplied to the delivery roller.
As described above, when the operation of the ink source roller is started, the ink film thickness set according to the pattern of the printing plate is immediately supplied to the ink delivery roller, so that the printing density can be stabilized at an early stage.
Thereby, the amount of paper loss at the time of printing can be reduced.

  The printing press according to the present invention is characterized in that, in the early supply step, the rotation speed and rotation time of the ink base roller are set so that the ink reaches the ink delivery roller.

  An ink supply method for a printing press according to the present invention includes a plate cylinder via an ink roller group including an ink delivery roller operated in conjunction with a machine speed from an ink fountain having a plurality of ink keys and an ink base roller. An ink supply device for supplying ink to the printing plate attached to the surface of the ink, and at least when a predetermined operating speed is reached, after the first predetermined time has elapsed, the ink source roller is started to operate, and the ink An ink supply method for a printing press that starts supply, and when printing is performed without cleaning an ink roller after a printing operation is completed, after the cylinder reaches the predetermined operation speed, the first predetermined The operation of the ink source roller is started after the elapse of a second predetermined time set longer than the time.

When continuous printing is performed without cleaning the ink roller after the printing operation is completed, excess ink is held in the ink roller group.
According to the present invention, since the second predetermined time from the cylinder insertion to the start of operation of the ink base roller is set longer than the first predetermined time, more ink is transferred from the ink roller group to the printing plate during that time. Will be supplied.
If more ink is supplied to the printing plate from the ink roller group, the ink film thickness distribution and ink amount in the ink roller group at the start of operation of the ink source roller will be in good condition, so the printing density will be reduced. It can be stabilized early.
Thereby, the amount of paper loss at the time of printing can be reduced.
The ink supply method for a printing press according to the present invention is characterized in that a plurality of the ink keys are set to a substantially constant predetermined opening, and a predetermined amount of ink film thickness is previously formed on the ink roller group.
Further, the ink supply method of the printing press according to the present invention is to rotate the ink base roller for a predetermined time by an ink key opening set corresponding to the pattern of the printing plate before the cylinder insertion, Following the formation of a predetermined amount of ink film thickness on the ink roller group, the ink source roller is driven to rotate for a predetermined time by the ink key opening set corresponding to the pattern of the printing plate before the cylinder insertion. (Early supply process).

  According to the present invention, it is possible to accurately supply ink at the time of printing and to stabilize the printing density at an early stage. As a result, the amount of lost paper during printing can be reduced.

Embodiments according to the present invention will be described below with reference to the drawings.
[First embodiment]
Hereinafter, a rotary printing press 1 used for newspaper printing according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a front view showing an overall schematic configuration of a rotary printing press 1.
The rotary printing machine 1 is provided with a plurality of paper feeding devices 3, a printing unit 5, a turn bar row unit 7, and a folding machine 9.

The paper feeding device 3 includes three pairs of arms 15 that rotatably hold a web 13 on which a web 11 is wound in a roll shape, and a paper splicing device (not shown).
When the web 11 is being fed from the web 13 attached to the arm 15a positioned at the paper feed position, the web 13 is waiting for the web 15 being prepared for paper splicing at the arm 15b located at the paper splicing position. .
When the web 11 of the rolled-up paper 13 that has been fed out decreases, the web 11 of the web 13 that is waiting is spliced.
In this way, the web 11 is continuously fed from the paper feeding device 3 to the printing unit 5.

The printing unit 5 includes a multi-color printing unit 5a that performs double-sided four-color printing and a two-color printing unit 5b that performs double-sided two-color printing.
The multi-color printing unit 5a and the two-color printing unit 5b are only examples, and appropriate printing units such as a single-color printing unit that performs double-sided monochromatic printing and a printing unit that performs four-color one-sided and two-sided printing are provided. Can be used.
The multi-color printing unit 5 a and the two-color printing unit 5 b perform predetermined printing on the web 11 supplied from the paper feeding device 3 and supply the web 11 to the turn bar array unit 7.

The turn bar row unit 7 includes a number of turn bars (not shown), and is configured to change the travel route of the web 11 from each printing unit 5a, 5b and change the overlapping order.
The folding machine 9 stacks a plurality of webs 11 sent from the turn bar row section 7 and vertically cuts them, vertically folds them with a triangular plate, further cuts horizontally and folds, and discharges them as a desired folded book. It is configured.

FIG. 2 is a front view showing a schematic configuration of one printing unit at the bottom of the printing unit 5b.
In the printing section, a plate cylinder 17 on which a printing plate 16 for forming a printed image is mounted, a blanket cylinder 19 for transferring an image formed on the printing plate of the plate cylinder 17 to the web 11, and a printing on the plate cylinder 17 are printed. An ink supply device 21 that supplies ink K to the image line portion of the plate and a dampening device 23 that supplies dampening water to the non-image line portion of the plate cylinder 17 are provided.

The ink supply device 21 includes ink form rollers 25 and 27, ink reciprocating rollers 29 and 31, ink kneading rollers 33 and 35, an ink delivery roller 37, an ink source roller 39, an ink key 41, and an ink fountain 43. And are provided.
The ink form rollers 25 and 27, the ink reciprocating rollers 29 and 31, the ink kneading rollers 33 and 35, and the ink delivery roller 37 constitute an ink roller group according to the present invention.
The ink reciprocating rollers 29 and 31 are made of metal and supported so as to be rotatable with respect to the frame and slidable in the axial direction. The ink reciprocating rollers 29 and 31 are configured to be rotated at substantially the same peripheral speed as the peripheral surface of the plate cylinder 17 and to be reciprocated in the axial direction by a drive source of the machine (not shown).

The ink kneading rollers 33 and 35 are made of rubber and are rotatably mounted. The ink kneading roller 33 is configured to be rotated with these rollers by being pressed against the ink reciprocating rollers 29 and 31.
The ink kneading roller 35 is configured to be rotated with these rollers by being pressed against the ink reciprocating roller 31 and the ink delivery roller 37.

The ink form rollers 25 and 27 have a rubber surface and are rotatably supported by a frame. The ink form rollers 25 and 27 are configured to be rotated by being pressed against the ink reciprocating roller 29 and the plate cylinder 17.
The ink delivery roller 37 is made of metal, is rotatably supported with respect to the frame, and is configured to be rotated at substantially the same peripheral speed as the peripheral surface of the plate cylinder 7 by a drive source of this machine (not shown).
The ink delivery roller 37 is installed so as to leave a minute gap with respect to the ink base roller 39.

The ink base roller 39 is made of metal and is rotatably provided. The ink source roller 39 is configured to be driven independently from the printer by a drive source (not shown). In this case, for example, during the printing operation, the printing machine is rotated while maintaining a certain relationship with the speed of the apparatus.
A plurality of, for example, 32 ink keys 41 are arranged side by side in the axial direction of the ink source roller 39 on the opposite side of the ink source roller 39 with respect to the ink delivery roller 37.
An ink fountain 43 is constituted by the ink source roller 39, the plurality of ink keys 41, and a side plate (not shown).

  The ink key 41 is made of metal and is a plate-like member. The ink key 41 is supported by a driving means (not shown) so as to be swingable with an end portion on the side away from the ink base roller 39 as a fulcrum. Each ink key 41 is swung by this driving means, and a gap (opening degree of the ink key 41) S between the tip of the ink key 41 and the ink source roller 39 is set.

The dampening device 23 includes a swim roller 45, a water reciprocating roller 47, and a spray dampener 49.
The water reciprocating roller 47 is made of metal and is supported so as to be rotatable with respect to the frame and slidable in the axial direction. The water reciprocating roller 47 is configured to be rotated at substantially the same peripheral speed as the peripheral surface of the plate cylinder 17 and reciprocated in the axial direction by a driving source (not shown).

The swim roller 45 is rotatably attached to the frame. The swimsuit roller 45 is configured to be rotated by being pressed against the water reciprocating roller 47 and the plate cylinder 17.
The spray dampener 49 is configured to spray and supply water to the water reciprocating roller 47.

The rotary printing press 1 is provided with a control unit that controls operation and the like, and an ink supply control unit 50 is provided therein.
The ink supply control unit 50 controls the ink supply to the printing plate 16, sets the gap S of each ink key 41, adjusts the speed of the ink roller group (drive control of this machine), and rotates the ink source roller 39. It has a function to perform control and the like.

The ink supply control unit 50 is provided with an ink supply start mode for starting operation and supplying ink to the printing plate 16 at a predetermined timing. In the ink supply start mode, there are provided an initial printing ink supply start mode J and a continuous printing ink supply start mode H in which the time from the cylinder loading to the start of operation of the ink source roller 39 is extended.
In the initial printing ink supply start mode J, an ink winding process M for forming a predetermined amount of ink film thickness on an ink roller group in advance and a printing plate pattern before cylinder transfer are set to a substantially constant predetermined opening degree. In this order, an early supply process N for rotating the ink base roller 39 for a predetermined time by the opening degree of the ink key 41 set in the above manner is provided.

The operation of the rotary printing press 1 according to the present embodiment configured as described above will be described.
The web 11 fed out from the web 13 held by the arm 15 in each paper feeding device 3 is sent to the multi-color printing unit 5a or the two-color printing unit 5b.
In the multi-color printing unit 5a or the two-color printing unit 5b, the following printing operation is repeatedly performed.

Each member of the printing unit is rotated as indicated by the arrows in FIG.
Water is supplied from the dampening device 23 to the non-image area of the printing plate 16 attached to the peripheral surface of the plate cylinder 17.
In the dampening device 23, the water reciprocating roller 47 rotates at substantially the same peripheral speed as the plate cylinder 17 while reciprocating in the axial direction, and the swim roller 45 is applied to the plate cylinder 17 and the water reciprocating roller 47 at a predetermined nip pressure. By being pushed and rotated, the plate cylinder 17 rotates at substantially the same peripheral speed.
The water sprayed from the spray dampener 49 is supplied to the water reciprocating roller 47, and the amount transferred to the water adhering roller 45 is adjusted by the nip pressure between the water reciprocating roller 47 and the water adhering roller 45. The water transferred to the swim roller 45 is supplied to the non-image portion of the printing plate attached to the plate cylinder 17 rotating at substantially the same peripheral speed.

The ink K is supplied to the image line portion of the printing plate by the ink supply device 21 to the printing plate in which water is supplied to the non-image area.
In the ink supply device 21, the gap S between the tip of each ink key 41 and the ink base roller 39 is set according to the line area ratio (picture) of the corresponding part of the printing plate 16 of each ink key 41. .
Each ink key 41 is set (preset) by a driving means (not shown) so as to be large when the required gap S, that is, the image area ratio of the corresponding portion is large, and small when it is small.

The ink K stored in the ink fountain 43 is drawn out by the ink source roller 39 through the position P between the tip of the ink key 41 and the ink source roller 39.
A part of the ink K on the ink source roller 39 is delivered to the ink delivery roller 37 at a position W where the ink source roller 39 and the ink delivery roller 37 are engaged.
The ink delivered to the ink delivery roller 37 is transmitted to the ink kneading roller 35, the ink reciprocating roller 31, the ink kneading roller 33, and the ink reciprocating roller 29.
The ink is supplied from the position T where the ink form rollers 25 and 27 and the plate cylinder 17 are engaged to the image line portion of the printing plate 16 attached to the peripheral surface of the plate cylinder 17.

At this time, the supply amount of the ink K supplied by the ink supply device 21 is adjusted by the gap S between the tip of the ink key 41 and the ink original roller 39 and the ink original roller 39 rotating at a low speed. The nip between the rollers is kneaded so as to gradually become thinner while the supply amount is reduced. The ink reciprocating rollers 31 and 29 reciprocate in the axial direction to further enhance the kneading effect.
This change in the ink film thickness is as shown in FIG.
In this way, the ink K (image) transferred to the image line portion of the printing plate 16 is transferred to the blanket cylinder 19. The image transferred to the blanket cylinder 19 is transferred to both surfaces of the web 11 running between the blanket cylinders 19 and 19 from bottom to top. Thereby, printing of one color is performed on both surfaces of the web 11.

  In this way, the web 11 that is color-printed on both front and back sides by the multicolor printing unit 5a and the web 11 that is two-color or single-color printed on the front and back sides by the two-color printing unit 5b are routed by the turn bar in the turn bar row unit 7. The order of overlap is adjusted according to the page structure of the newspaper.

  The plurality of webs 11 sent from the turn bar row portion 7 to the folding machine 9 are vertically folded and transversely cut. The cut web 11 is laterally folded by a folding cylinder to form a folded book and conveyed outside the machine.

Next, the ink supply operation at the time of printing will be described.
First, the ink roller cleaning is performed to wash out the ink of the previous printing operation. Therefore, ink is not held in the ink roller group.
In this case, the ink supply control unit 50 starts ink supply in the initial printing ink supply start mode J.

  FIG. 4 shows the flow of the initial printing ink supply start mode J. In the initial printing ink supply start mode J, first, the ink winding process M is performed. FIG. 5 shows the state change of each part with the elapsed time at this time and the film thickness change state of the ink K in the ink supply device 21.

With the cylinders removed, all ink keys are set to a certain opening, for example, 50%, and the rotation speed of the ink source roller 39 is set to a predetermined speed, for example, 20% of the maximum speed. To start supplying ink (step S1).
At this time, the ink roller group (the ink delivery roller 37, the ink reciprocating rollers 31, 29, the ink kneading rollers 35, 33, and the ink application rollers 25, 27) is accelerated for a predetermined time, for example, 36 seconds, and then, the predetermined speed, For example, it is operated so that 60,000 revolutions / hour is maintained for a predetermined time, for example, 20 seconds, and then decelerated for a predetermined time, for example, 36 seconds.
At this time, like the ink roller group, the plate cylinder 17 driven by this machine is also rotated at the same peripheral speed as the ink roller group.

When the ink source roller 39 is operated for a predetermined time, for example, 3.5 seconds, the rotation of the ink source roller 39 is stopped (step S2).
The predetermined time for stopping the ink source roller 39 is set so that a predetermined amount of ink can be supplied.
The ink key 41 starts to be closed when the ink base roller 39 is stopped.
At this time, the ink K exists in a thickness corresponding to the opening degree of the ink key 41 set from the position P to the position W on the ink source roller 39, and the ink roller group is slightly tapered depending on the amount of ink supplied. Exists in a state.

Next, with the ink key 41 completely closed, the ink source roller 39 is rotated at the same constant speed as in Step S1 (Step S3).
Along with the stop of the ink roller group, the ink source roller 39 is also stopped (step S4).
During this time, the ink K from the position P to the position W of the ink source roller 39 is transferred to the ink transfer roller 37, while the ink key 41 is closed, so that the position from the position P to the position W of the ink source roller 39 is closed. In this state, ink K is not present.
Since the ink K is circulated in the ink roller group, an ink film having substantially the same thickness is formed in each part.

As a result, the ink roller group is supplied with ink for a predetermined time (that is, a predetermined rotation amount: a predetermined distance) at a constant ink key 41 opening S, and the ink winding process M is completed.
Thus, in the ink winding process M, since the ink key 41 is set to a substantially constant predetermined opening S, the amount of ink to be supplied can be set strictly.
For this reason, it is possible to prevent the ink supplied to the printing plate from becoming excessive or insufficient.

Next, the opening S of each ink key 41 is set according to the image area ratio (picture) of the corresponding part of the printing plate 16 (step S5).
Thus, when the ink base roller 39 rotates, ink having a distribution in which the thickness varies in the width direction according to the opening S of each ink key 41 is supplied onto the ink base roller.
At this stage, the ink film thickness in the ink roller group does not vary greatly.

Next, the early supply process N is started.
First, the printer is driven and a printing operation is started (step S6). Along with this, the ink roller group is accelerated.
Next, the ink source roller 39 is operated at a predetermined speed, for example, 40% of the maximum speed, for a predetermined time t0, for example, 4.2 seconds (step 7).
As a result, an ink having a distribution whose thickness varies in the width direction corresponding to the pattern area ratio of the printing plate 16 is supplied onto the ink base roller 39, and finally the ink having this distribution from the position P to the position W. (Indicated by diagonal lines in the ink film thickness of FIG. 5).
The rotation speed and rotation time t0 of the ink base roller 39 are preferably set so that the ink reaches the position W.

Next, cylinder filling is performed, and the ink form rollers 25 and 27 are brought into contact with the printing plate 16 mounted on the surface of the plate cylinder 17 (step S8).
As a result, the ink K is supplied from the ink form rollers 25 and 27 to the printing plate 16.
Accordingly, the ink film thickness in the ink roller group changes so as to taper toward the plate cylinder 17.

After a lapse of a predetermined time (first predetermined time) t1, for example, 4 seconds, from the cylinder insertion, the ink source roller 39 is driven to rotate at a constant ratio with respect to the plate cylinder peripheral speed (step 9).
At this time, the ink K having a distribution in which the thickness varies in the width direction corresponding to the pattern area ratio of the printing plate 16 exists up to the position W on the ink source roller 39, so that the ink source roller 39 starts rotating. Immediately, the ink is supplied to the ink delivery roller 37.
As described above, when the operation of the ink source roller 39 is started, the ink film thickness set according to the pattern of the printing plate is immediately supplied to the ink delivery roller 37, so that the printing density can be stabilized at an early stage. .
As a result, the amount of lost paper at the time of printing can be significantly reduced.

On the other hand, after printing is completed, when printing is performed without performing ink roller cleaning, the ink supply control unit 50 starts ink supply in the continuous printing ink supply start mode H.
FIG. 6 shows the flow of the continuous printing ink supply start mode H. FIG. 7 shows the state change of each part with the elapsed time at this time and the film thickness change state of the ink K in the ink supply device 21.
In the continuous printing ink supply mode H, the printing plate 16 may be used as it is or may be replaced. However, the ink roller cleaning is not performed anyway, and the opening degree S of the ink key 41 is usually set. If not changed.

A stop signal is transmitted from the control means (not shown) to the rotary printing press 1 during the printing operation (step S11).
Thereby, the cylinder is removed and the operation of the rotary printing press 1 that has been decelerated is stopped.
Since there is a little time from the drum removal to the stop of the ink source roller 39 and the ink roller group, the ink is transferred from the ink source roller 39 to the ink delivery roller 37 and the presence of the ink stored in the ink roller group For this reason, when the operation is stopped, a predetermined amount or more of ink remains in the ink roller group.
Further, since the ink K is circulated to some extent in the ink roller group, the thickness is being made uniform in each part.

Next, the printer is driven and a printing operation is started (step S12). Along with this, the ink roller group is accelerated.
At this time, since the ink base roller 39 is not driven to rotate and is not encased, the ink K is circulated in the ink roller group, and the thickness is made uniform in each part.
When the operating speed reaches a predetermined speed, cylinder filling is performed, and the ink form rollers 25 and 27 are brought into contact with the printing plate 16 mounted on the surface of the plate cylinder 17 (step S13).
As a result, the ink K is supplied from the ink form rollers 25 and 27 to the printing plate 16.
Accordingly, the ink film thickness in the ink roller group changes so as to taper toward the plate cylinder 17.

After a lapse of a predetermined time (second predetermined time) t2, for example, 9 seconds, from the cylinder insertion, the ink source roller 39 is driven to rotate at a constant ratio with respect to the plate cylinder peripheral speed (step 14).
The predetermined time t2 from the cylinder insertion to the start of the operation of the ink source roller 39 is set to be longer than, for example, 9 seconds and the predetermined time of the initial printing ink supply start mode J, for example, 4 seconds. Therefore, more ink K is supplied to the printing plate 16 (web 11).
When more ink K is supplied from the ink roller group to the plate 16, the ink K in the ink roller group is reduced by the start of operation of the ink source roller 39. Since ink is supplied from the ink form rollers 25 and 27 to the printing plate 16, the film thickness distribution of the ink K is tapered toward the ink form rollers 25 and 27.
As described above, since the film thickness distribution and the ink amount of the ink K are in a good state, the printing density can be stabilized at an early stage.
Thereby, the amount of paper loss at the time of printing can be reduced.

  In addition, although the above-mentioned each predetermined time and predetermined speed give the number as an example, these are suitably changed according to printing conditions.

In the present embodiment, the ink supply control unit 50 includes the initial printing ink supply start mode J and the continuous printing ink supply start mode H, but may include either one.
Depending on the status of the printing operation of the rotary printing press 1, for example, if there is almost new printing, even if only the initial printing ink supply start mode J is provided, the same effect of reducing the waste paper can be obtained.

Further, in the present embodiment, the present invention is applied to the rotary printing press 1 for newspaper printing, but it may be applied to a commercial offset rotary printing press or a sheet-fed offset rotary printing press.
In this case, even if the ink supply device is configured to reciprocate the ink delivery roller to supply ink from the ink source roller to the ink roller group, the number of reciprocations or the reciprocation time is set, and the ink to the ink roller group is set. By controlling the supply amount, the same effect as in the present embodiment is brought about.
Of course, various modifications can be made without departing from the scope of the present invention.

1 is a front view showing an overall schematic configuration of a rotary printing press according to an embodiment of the present invention. It is a partial front view which shows schematic structure of the printing part concerning one Embodiment of this invention. It is a schematic diagram which shows the ink film thickness distribution of the ink roller group at the time of printing. It is a flowchart of the first printing ink supply start mode of one Embodiment of this invention. It is a schematic diagram which shows the state change of each part with the elapsed time at the time of the first printing ink supply start mode of one Embodiment of this invention, and the film thickness change of the ink in an ink supply apparatus. It is a flowchart of the continuous printing ink supply start mode of one Embodiment of this invention. It is a schematic diagram which shows the state change of each part with the elapsed time at the time of the continuous printing ink supply start mode of one Embodiment of this invention, and the film thickness change of the ink in an ink supply apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotary printing machine 16 Plate 17 Plate cylinder 21 Ink supply device 37 Ink delivery roller 39 Ink original roller 41 Ink key 43 Ink fountain 50 Ink supply control part H Continuous printing ink supply mode J Initial printing ink supply mode K Ink M Ink winding process N Early supply process

Claims (8)

Ink that supplies ink to a printing plate attached to the surface of the plate cylinder through an ink roller group including an ink delivery roller operated in conjunction with a machine speed from an ink fountain having a plurality of ink keys and an ink base roller A feeding device;
And an ink supply control unit that controls the supply of ink to the printing plate and starts the operation of the ink base roller after the first predetermined time has elapsed, at least when the predetermined operation speed is reached. Printing press,
In the control unit,
When printing is performed without cleaning the ink roller after the printing operation is completed, the continuous printing in which the second predetermined time from the cylinder insertion to the start of the operation of the ink source roller is set longer than the first predetermined time. A printing machine comprising an ink supply start mode.   An initial printing ink supply start mode further comprising an ink winding step in which a plurality of ink keys are set to a substantially constant predetermined opening and a predetermined amount of ink film thickness is formed in the ink roller group in advance is further provided. The printing machine according to claim 1. The ink winding step is
The ink source roller is stopped after a predetermined time and the ink key is closed;
The printing press according to claim 2, further comprising a step of rotating the ink base roller for a predetermined time in a state where the ink key is closed. The first printing ink supply start mode is
And an early supply step of rotating the ink source roller for a predetermined time by an ink key opening set corresponding to the pattern of the printing plate before the cylinder filling, and the early supply step following the ink winding step The printing press according to claim 2, wherein the printing press is implemented.   5. The printing press according to claim 4, wherein in the early supply step, the rotation speed and the rotation time of the ink base roller are set so that the ink reaches the ink delivery roller. Ink that supplies ink to a printing plate attached to the surface of the plate cylinder through an ink roller group including an ink delivery roller operated in conjunction with a machine speed from an ink fountain having a plurality of ink keys and an ink base roller A supply device,
At least the ink supply method of a printing press that starts the operation of the ink source roller after the first predetermined time has elapsed after the cylinder is put in at a time when the predetermined operation speed is reached, and starts the ink supply,
After printing, when printing without performing ink roller cleaning, after entering the predetermined operating speed, after the second predetermined time set longer than the first predetermined time, An ink supply method for a printing press, wherein the operation of an ink base roller is started.   7. The ink supply method for a printing press according to claim 6, wherein the plurality of ink keys have a substantially constant predetermined opening, and a predetermined amount of ink film thickness is formed in advance on the ink roller group.   Before the cylinder insertion, the ink source roller is rotated for a predetermined time by the ink key opening set corresponding to the pattern of the printing plate, and a predetermined amount of ink film thickness is formed in the ink roller group in advance. 8. The printing press according to claim 7, wherein the ink fountain roller is driven to rotate for a predetermined time by an ink key opening set corresponding to a pattern of the printing plate before the cylinder insertion. Ink supply method.

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