JPH0434942B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application This invention provides a rotary letterpress printing machine, particularly a lightweight letterpress rotary printing machine that does not require adjustment of the amount of ink (keyless) that sends water-based ink using a mesh roller.
The present invention relates to automatic control of the operation, that is, a device equipped with a device that successively sequentially controls each step in the transition from normal stop to steady operation and then to normal stop according to a predetermined procedure.

(b) Prior Art It is known that the use of water-based ink in printing presses, unlike the case of oil-based ink, has the advantage of preventing ink rub-off, staining, etc.

Conventionally, flexographic printing machines that supply water-based ink using an anilox roller are well known, but because the plates are soft, the printed characters and lines appear thick, making it difficult to obtain clear prints.

On the other hand, it is also known that if a water-based ink is used in a letterpress rotary press and the plate is made of a water-resistant material, clear printing can be obtained and the above-mentioned concerns can be resolved.

Furthermore, the ink supply system of the letterpress rotary press includes an anilox roller (also known as
Light-weight letterpress rotary presses that do not require adjustment of the ink amount (commonly known as keyless) and incorporate a mesh roller (mesh roller or mesh roller) are well known (published by the Japan Newspaper Association, "Newspaper Printing" Printing Edition Revised Edition No. 393, and Tokyo Kikai Co., Ltd.) (See "Tokyo Kikai Seisakusho 100 Years of History" No. 354-355 published by Seisakusho).

On the other hand, there is a mechanism (commonly known as a trip) that connects and disconnects the cylinder and rollers of the ink supply system.
Conventionally, these have been mainly attached to the blanket cylinder and inking roller of an offset rotary press (see the above-mentioned ``Newspaper Printing'', Parts 206-207).
However, recently, it has come to be attached to the inking roller and doctor blade of letterpress rotary presses (see the above-mentioned "100 Years of History").

Furthermore, on the other hand, the work of cleaning and removing ink from each cylinder and roller after printing has conventionally been performed on the blanket cylinders of offset printing machines, and has also been carried out on the dampening rollers at appropriate times (see above). (See "Newspaper Printing" No. 251). However, cleaning and removing ink from the drums and rollers of letterpress rotary presses has not been carried out in the past (see "Newspaper Printing", Parts 164 to 168).

(c) Problems to be Solved by the Invention Although the advantages of using water-based ink in a printing press have been described above, there are also disadvantages.
In other words, the water in the excess water-based ink supplied to each roller evaporates over time and solidifies. In particular, when the water-based ink that adheres to the cells (indentations) of the mesh roller hardens, it causes clogging and normal ink flow. It becomes difficult to supply the quantity. Therefore, it is desirable to carefully wash away the water-based ink left on each roller immediately after printing is completed.

However, all conventional cleaning and removal work for water-based ink has been done manually, that is, after the connection between each roller has been manually separated, the surface of each roller has been manually cleaned and removed. Not only is this work time-consuming and labor-intensive, but it is considered dirty work that makes workers feel uncomfortable, and no one likes to do it. Also, due to omissions in cleaning procedures and mistakes, etc.
There was also waste, with a relatively large amount of wasted paper.

Therefore, in order to realize automatic control of the operation of a letterpress rotary printing press that uses water-based ink and does not require ink amount adjustment (keyless), it is necessary to automate the work of cleaning the water-based ink that adheres to each cylinder and roller. Furthermore, in order to enable automatic cleaning, it is a prerequisite to enable automatic trip-on-off means for each cylinder and roller, and these issues must be solved in one step. That was what was hoped for.

(d) Means for Solving the Problems The structure of the present invention is as follows: First, in the initial stage of deceleration when the printing operation is normally stopped, the rotation of the printing press in steady operation is decelerated by inputting an auto-stop ON signal, and the ink is stopped. Then, in the automatic cleaning stage, the cleaning liquid supply system starts cleaning the bottom roller by inputting a signal that detects that the rotational speed of the plate cylinder has been decelerated to less than a certain number of times during steady operation. It operates toward the circumferential surface and stops its operation after a certain period of time or after the number of rotations of the plate cylinder reaches a predetermined number, and further,
In the automatic cleaning auxiliary stage, an automatic control system is provided to trip off one or all of the doctor blade, mesh roller, plate cylinder, and form roller immediately before and after cleaning.

Alternatively, in addition to the above configuration, as an automatic control system during the development of printing operation, first, the printing press is started by inputting an auto-run on signal, and then,
a startup stage in which the speed is automatically increased; a stage immediately after the startup in which the mesh roller and/or doctor blade is tripped on before the ink supply is turned on; and a stage immediately after startup in which the plate cylinder and/or form roller are tripped on before or after the ink supply is turned on; A steady operation stage is provided in which the speed increases to a constant speed upon input of a signal that detects that the rotational speed of the engine has reached a specific value.

(e) Function A cleaning liquid supply system is specially installed near the circumferential surface of the lowest roller, for example, a mesh roller, so that the cleaning liquid is sequentially transferred from the lowest roller to the upper rollers and the cylinder. Therefore, in order to prevent the diluted surplus water-based ink from remaining on the circumferential surface of each roller and cylinder, the connection between each roller and cylinder was tripped off to promote liquid dispensing, so that the peripheral surface of each roller and cylinder was Since the residual water-based ink is automatically washed off according to the ink washing mode according to the soiling condition, a route for supplying an appropriate amount of ink is secured.

The tripped-off rollers and cylinders are automatically tripped-on before and after ink supply before entering steady operation, so ink is supplied and printing becomes possible.

(f) Embodiment FIG. 1 shows a keyless letterpress rotary printing press according to the present invention, in which left and right printing units PU1 and PU2 are installed together, so that monochrome printing is performed on both the front and back sides of the web W, and each printing unit PU1 and PU2 each have only five rollers and cylinders, namely, plate cylinder 1, impression cylinder 2, form rollers 3 and 4, and mesh roller 5.
, an ink supply section 6 with a doctor blade, a cleaning liquid supply section 7, and a pan 8 for collecting washed waste liquid containing surplus ink.

The plate cylinder 1 is attached to a regular letterpress, water-resistant letterpress or flexographic plate on its circumferential surface, no cushion material is placed in the plate, and the left and right shafts supporting the plate cylinder are air cylinders, etc. (not shown). is tripped by the fluid actuator and the link mechanism, and the plate cylinder 1 is displaced between the solid line and the broken line by the trip.

The impression cylinder 2 is equipped with a conventionally known letterpress blanket on its circumferential surface. However, when using a flexo plate, the blanket is not attached and the metal plate is used as is, as is the case in the past.

The two form rollers 3 and 4 are each equipped with a trip mechanism (not shown) so that they can be displaced between the inner solid line position and the outer broken line position.The mesh roller 5 has fine uniform cells on its circumferential surface. (dents) are uniformly scattered at a density of, for example, 150 to 500 dents per inch, and the entire circumferential surface of the roller, including the inner surface of the cells, is made of a material that is both hydrophilic and wear-resistant, such as chromium or ceramic. It is coated with Metsuki.

As shown in the figure, the mesh roller 5 is provided with a trip mechanism (not shown) that can move vertically (indicated by solid lines and broken lines).

The ink supply section 6 supplies water-based ink to the circumferential surface of the mesh roller 5 while circulating ink at a required level using a pump, and the water-based ink supplied to the circumference of the mesh roller 5 is stored in the upper part of the ink supply section 6 It is immediately scraped off with the tip of a doctor blade (not shown). Therefore, the water-based ink that is allowed to pass is limited to that within the cells (recesses) on the circumferential surface of the mesh roller 5. This limitation is as accurate as if it were measured by a scale, and therefore the appropriate amount of ink to be supplied is determined at once, and there is no need for any subsequent adjustment to increase or decrease the amount of ink. In the present invention, a trip mechanism (not shown) is provided so that the ink supply section with a doctor blade can be angularly displaced between a solid line position and a broken line position about the shaft 6a, and the trip mechanism is operated by pneumatic means. or similar means and a linkage mechanism.

The doctor blade is pressed against the circumferential surface of the mesh roller 5 at a reverse angle, and the material of the blade may be steel, but water-resistant material is more preferable, and plastic material can also be used. The doctor blade can also be tripped on and off by air pressure, etc., which is useful for other purposes during cleaning.
It also works effectively when replacing blades.

The advantages and disadvantages of using water-based ink are as described above.

Reference numeral 7 denotes a cleaning liquid supply section, which is installed toward the circumferential surface of the lowest roller of the ink supply system, for example, the mesh roller in the illustrated embodiment, for example, the mesh roller 5 in the illustrated embodiment, and is independent as shown in the figure. Alternatively, the mesh roller 5 can be installed in the ink supply unit 6 to save space, and the mesh roller 5 can be sprayed with an aqueous cleaning liquid, or sprayed with a roller or other means, and then the foam roller 3 and the mesh roller 5 can be installed. 4. In some cases, plate cylinder 1
and wash off excess water-based ink adhering to their surrounding surfaces.

The washed waste liquid containing excess ink washed off from the circumferential surface of each roller is basically scraped off with a doctor blade and flows down into the pan 8 provided below the mesh roller 5, and the drained waste liquid is drained into the drain 8a. The ink and the like flow out through the piping to the ink mixing device. Note that the waste liquid on the circumferential surface of the roller can also be removed by being transferred and adhered to paper (web).

Figure 2 is a time chart showing each stage of automatic operation control in relation to the passage of time and the rotational speed (rpm) of plate cylinder 1.The trip-on state of each part during steady operation (center of Figure 2) is The trip-off state of each part at the time of stop (left end and right end in FIG. 2), which is indicated by the solid line position in FIG. 1, is classified and shown in FIG. 3.
The trip-off state of each part during washing (front of the right end in Figure 2) is classified and shown in Figure 5, and the automatic control means (for example, 10 The flowchart in Figure 4 shows the automatic control procedures (for example, 100 steps, some of which are omitted) from steady operation (center of Figure 2) to normal stop (right end of Figure 2) through cleaning.
is shown in the flowcharts of FIGS. 6 and 7. However, the illustrated procedure is merely an example, and the illustrated flow does not necessarily have to be followed at each stage, and the trip sequence of each part can be replaced as appropriate.

Therefore, the automatic motion control procedure according to the present invention will be summarized below.

First, in FIG. 3, the state of each part when stopped is a state S9 where all trips are on and a state S8 where all trips are off, and intermediate states S1 and S8 where some trips are on and other trips are off.
There are 10 types in total: 2, S3, S4, S5, S6, S7, S10.

Next, in FIGS. 2 and 4, after inputting an autorun on signal to the printing machines in the various stopped states S1 to S10 shown in FIG. 3 to start them,
To automatically increase speed and to automatically start ink supply in the middle of the speed increase. They are always executed regardless of the solar differences of each stop. If there is trip-off in one or all of the parts when stopping, in order to make them trip-on, the mesh roller and/or doctor blade should be trip-on before the ink supply is turned on, and before or after that, Trip-on the plate cylinder and/or form roller.

Furthermore, returning to FIG. 2, when the trip-on of each part is completed and the rotation speed of the plate cylinder reaches a specific value, for example 600 rpm in the illustrated embodiment, the speed is changed from increased speed to constant speed by inputting a signal to detect this. and then perform steady operation.

Now, when it is desired to stop the printing press normally, as shown in Fig. 1, all the parts during steady operation are in the trip-on state (solid line positions). Under such conditions, as shown in FIGS. 2 and 6, an auto-stop ON signal is input to the printing press to automatically decelerate and stop the ink supply.

Next, the number of rotations of the plate cylinder is less than or equal to a certain number of times during steady operation, for example, in the illustrated embodiment, it is 1/10 or less.
Upon input of a signal that detects deceleration to 60 rpm or less, the cleaning liquid supply unit 7 operates toward the bottom roller, that is, the circumferential surface of the mesh roller 5, and supplies cleaning liquid, and after a certain period of time, for example, 30 seconds, the operation stops automatically. Immediately before and/or immediately after the cleaning, one or all of the doctor blade, mesh roller, plate cylinder, and form roller are tripped off (the first (See Figures 6 and 7). FIG. 5 shows the trip-off state of each part during cleaning, with a state W1 of all trip-on and a state W9 of all trip-off being the two extremes, and an intermediate state W of partial trip-off and other trip-on states.
2, W3, W4, W5, W6, W7, W8, W1
0, there are 10 types in total.

Immediately after cleaning, there are 10 trip-off states for each part for each of the 10 cleaning states, ie, a total of 100 states, and 10 stop states are reached from these 100 states (see FIGS. 6 and 7).

(g) Effects of the invention As detailed above, when water-based ink is used in a simple, lightweight letterpress rotary printing press that uses a mesh roller and a doctor blade and does not require ink amount adjustment (keyless), it is possible to prevent ink rub-off and stain-through. However, unlike oil-based ink, water-based ink has the advantage that excess water-based ink that remains on various parts of the roller after printing dries and hardens relatively quickly, and especially cells (dents) on the mesh roller. If it adheres to the inside of the ink and hardens, it will cause clogging, making it difficult to supply a normal amount of ink, and conventionally all excess water-based ink has been washed and removed manually.

In contrast, in the present invention, while automating the trip on/off means of each part, an automatic cleaning means for supplying cleaning liquid to the roller circumferential surface is incorporated in connection with the automation, and the rotary letterpress printing machine is operated based on these automatic cleaning means. By achieving automatic control, we no longer need to carry out time-consuming dirty work, and at the same time, we are able to reduce the number of workers involved. The automatic operation control according to the present invention applies to all letterpresses that use water-based inks,
That is, it can be used in letterpress printing machines that also include flexographic plates.

[Brief explanation of drawings]

The drawings show a specific embodiment of the invention. FIG. 1 is an explanatory diagram showing the configuration of each part of a sequence-controlled keyless lightweight letterpress rotary printing press in its steady operating state (solid line, ie, trip-on), and the broken line shows the trip-off state during stoppage. Fig. 2 is a time chart showing each stage of control in relation to the passage of time and the plate cylinder rotation speed, Fig. 3 S1 to S10 are explanatory diagrams categorizing the states of each part during stoppage by trip, and Fig. 4 is a flowchart from various stop states to startup to steady operation, Figure 5 W1 to W10 is an explanatory diagram classifying each part by trip during cleaning, and Figure 6 is from steady operation to cleaning to stop. The flowchart of FIG. 7 is a flowchart of the case from the cleaning state W9 of FIG. 6 to the stop. W...web, PU1 and PU2...printing department, 1
...Print cylinder (with trip mechanism), 2...Impression cylinder, 3
and 4...form roller (with trip mechanism),
5...Mesh roller (with trip mechanism), 6
...Ink supply unit with doctor blade (equipped with trip mechanism), 6a... Base shaft for trip, 7...
...Washing liquid supply unit, 8...Pan for collecting washed waste liquid containing excess ink, 8a...Drain, S1-S1
0... Printing press trip-off stop status, W1~
W10: Trip-off cleaning status of the printing press.

Claims (1)

[Scope of Claims] 1. In the ink supply system of a letterpress rotary printing press that is equipped with a mesh roller and uses water-based ink, the following automatic control system that operates when the printing operation is normally stopped, that is, during steady operation by inputting an auto-stop ON signal, The initial stage of deceleration slows down the rotation of the printing press and stops the supply of ink, and the cleaning liquid is supplied by inputting a signal that detects that the rotation speed of the plate cylinder has been decelerated to less than a certain number of times during normal operation. an automatic cleaning stage in which the system operates toward the circumferential surface of the lowest roller and stops its operation after a certain period of time or after the number of rotations of the plate cylinder reaches a predetermined number; and immediately before and/or after the cleaning. A rotary letterpress printing press having an automatic control system comprising an automatic cleaning auxiliary stage for tripping off one or all of the doctor blade, mesh roller, plate cylinder and form roller. 2. In the ink supply system of a rotary letterpress printing press that is equipped with a mesh roller and uses water-based ink, the following automatic control system is activated when the printing operation progresses: the printing press is started by inputting an autorun ON signal, and then the speed is automatically increased. a starting stage in which the mesh roller and/or doctor blade is tripped on before the ink supply is turned on; a stage immediately after the startup in which the plate cylinder and/or form roller is tripped on before or after the ink supply is turned on; The automatic control system consists of a steady operation stage in which the speed increases to a constant speed upon input of a signal that detects that the printing operation has been reached, and the next automatic control system that operates when printing operation normally stops, that is, the automatic An initial stage of deceleration in which the rotation of the printing press during steady operation is automatically decelerated by input and the supply of ink is stopped;
Upon input of a signal that detects that the rotational speed of the plate cylinder has been reduced to a certain fraction of that during steady operation, the cleaning liquid supply system operates toward the circumferential surface of the lowest roller, and after a certain period of time has elapsed or An automatic cleaning stage in which the plate cylinder stops its operation after reaching a predetermined number of revolutions, and an automatic cleaning aid in which one or all of the doctor blade, mesh roller, plate cylinder, and form roller are tripped off immediately before and/or immediately after the cleaning. A letterpress rotary printing press equipped with an automatic control system consisting of stages and.