JPS624163A - Intermittent feeder of continuous sheet - Google Patents

Abstract

PURPOSE:To change the intermittent feed length, reduce the interrupt time, and improve accuracy by intermittently driving a pair of pull roll sections provided on the upstream and downstream sides of a machining section machining a running continuous sheet at the synchronous timing in the longitudinal direction. CONSTITUTION:Two pull roll sections 16, 17 intermittently feeding a sheet 3 in the longitudinal direction are arranged on the upstream and downstream sides of a printing section 10, and the sheet 3 is invariably held by them. The sheet 3 is fed forward during the forward acceleration period of the pull roll sections 16, 17, the constant- speed period after acceleration for print-machining, and the deceleration and stop period after the printing is over. Next, the sheet 3 is withdrawn toward the upstream side by the quantity equal to the advance quantity toward the downstream side during the acceleration, deceleration, and stop period via the reverse drive of the pull roll sections 16, 17 to eliminate blank spaces between printed sections on the sheet 3. The intermittent feed timing of the sheet 3 is obtained by adjusting the pull roll section drive timing of a drive unit. Accordingly, the intermittent feed length can be changed, the interrupt time can be reduced, and the intermittent feed accuracy can be improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to machines that process continuous sheets, such as flexo rotary printing presses, lithographic rotary printing presses, rotary die cutters, flat plate punching machines, etc., and is particularly applicable to rotary printing. This invention relates to an intermittent feeding device for continuous sheets for sequentially printing a predetermined size on each printing section of a web or other continuous sheet at any printing length within the circumferential dimension of the printing cylinder of the machine.

[Conventional technology]

FIG. 12 shows a typical continuous sheet (hereinafter referred to as sheet) rotary printing machine. Now, the roll-shaped sheet 1 is axially suspended in the center by the unwinding machine 2, and is pulled and pulled by the pull roller 11, so that it is rotated in the direction of the arrow and rewound.
Proceed in the direction of 0. The rewound sheet 8 passes through the winding roll 4 between the plate cylinder 5 and the impression cylinder 6 of the printing section 10 and is printed. In this example, the printing section 10 is 8 rough watered,
Generally, there are printing areas for three to six colors depending on the number of colors to be printed. The printed sheet 8 has a pair of pullrows tV
11 and pulled, and further by a winder 13,
It is wound up again to the low (low) v12 state. Furthermore, the printing mechanism shown in FIG. 13 transfers the ink 21 in the ink reservoir 8 onto the surface of the printing plate 14 attached to the second plate cylinder 5 by the ink adhesion low/L'7, and further onto the surface of the sheet 3. Printing is done. For ink deposition, excess ink (more than the necessary amount of ink) on the surface of the roller Lv7 is scraped off by the doctor grade 9 and flows back into the ink reservoir 8.

In addition, the outer peripheral surface speeds of the pull roller tL/11, the impression cylinder 6, and the printing plate 14 are matched so that the traveling speed of the sheet 3 matches the surface peripheral speed of printing.

Further, the rewinding machine 2 is equipped with a brake device (not shown) for the roll 1 so that the sheet 3 is unwound more than necessary due to the inertia of the low V1 and the sheet does not become sagging.

The winder 18 is also equipped with a drive device (not shown) for the row 1v12 for winding up the sheet 3 fed through the pull row/l/11.

The length of printing on a sheet in such a rotary printing press is determined by the arc length of the printing plate 14, and this maximum length is less than or equal to the circumferential length πD of the outer diameter of the printing plate.

Now, the repetition length is determined by the arc length of the printing plate 14, but if this length is smaller than the circumference length πD.

There are blank spaces that are not printed. This blank space is completely unnecessary and will be cut and discarded in the next process after printing and winding. Therefore, in the conventional machine, the following proposals have been made to reduce this blank area.

(1) A method of changing the outer diameter dimension (D) of the plate cylinder 5 according to the printing length, that is, a method of replacing the first plate cylinder 5.

(I) A method in which either the upper or lower part of the pull roll, which is rotating at a constant rate as shown in FIG. 14, is moved up and down in accordance with the printing length.

In the example shown in FIG. 14, the lower pull roll clamps and pulls the sheet while it is ascending, and the sheet is stopped while it is descending.

In addition, since printing is performed only while the sheet is running, the sheet intermittent feeding method changes the raising and lowering timing of the pull roll depending on the desired printing length.

saliva) On one side of the pull-row/L' 11 shown in Fig. 15,
The tensioning member 22 of the sheet 3 is attached, and its surface circumferential velocity is made to match the surface velocity of the printing plate 14 (that is, the outer diameters of the pull roll and the plate cylinder are the same and they rotate synchronously), and the tensioning member 22 is The arc length dimension of the member.

A method for intermittent feeding of sheets whose length is longer than the arc length of the printing plate 14.

[Problem that the invention seeks to solve]

The above measures (I), (II), and (Ill) have been proposed in the past, but each had the following problems.

Disadvantages of (1): This method is the most commonly used method, but the work of replacing the plate cylinder every time the printing length changes is complicated, the printing mechanism is complicated, and the most The disadvantage is that a desired number of expensive plate cylinders with different circumferences, ie, diameters, must be prepared.

Therefore, the manufacturing cost of the printing sheet becomes high.

Disadvantages of (I[): This method is an improvement measure to compensate for the disadvantages of (1). In this case, the sheet is clamped and pulled by rolls rotating at a constant speed, so the stopped sheet is instantly accelerated by the pull roll, but strictly speaking, the sheet matches the surface speed of the pull roll. Slip occurs between the pull roll and the sheet, and the amount of slip changes depending on the machine operating speed, sheet thickness, surface condition of the sheet and pull roll, sheet tension, etc., so changes and variations in the amount of slip occur due to the difference in the sheet. Directly linked to changes in repeat feed length. On the other hand, a similar phenomenon occurs when the sheet is stopped, making it impossible to obtain a highly accurate repeated feed length.

Disadvantages of (lit): This GI[) method is also an improvement measure to compensate for the disadvantages of (1). However, as in II), when a stationary sheet is clamped by a tension member attached to a pull roll rotating at a constant speed, slipping occurs between the sheet and the tension member due to the instantaneous acceleration of the sheet. do. Furthermore, since the sheet is accelerated more instantaneously than in case (II), a large tensile force is generated on the sheet during acceleration, causing the sheet to elongate and flutter.

Meandering and the like occurred, making it impossible to obtain a highly accurate repeated feed length, especially at high speeds. In addition, the tension member must be replaced every time the repeated feed length changes, and it is necessary to prepare a desired number of tension members with different arc lengths.

This point had the same drawback as (I). Furthermore, when this tension member is made of plastic, rubber, etc., durability, mainly wear, is a problem. (When worn, the amount of slip changes when the sheet is instantaneously accelerated, further reducing accuracy.) Also, since high precision is required when manufacturing with metal, manufacturing costs will increase. There was a problem to be solved.

[Means for solving problems]

The present invention has been proposed in view of the problems of the prior art, and includes a continuous sheet intermittent feeding device that runs a continuous sheet and processes the same sheet midway through the process. A high-speed, high-precision intermittent feeding device for continuous sheets, which is equipped with a pair of pull rolls that can hold and feed the sheets back and forth, and a drive device that drives the pull rolls intermittently in the front and back directions at synchronized timing. This is what we are trying to provide.

[Effect]

The present invention has two sets of pull roll sections that intermittently feed sheets in the front-back direction, one of which is disposed downstream of the sheet processing section and the other one of which is disposed upstream of the sheet processing section, and each of which continuously feeds the sheet. The sheet is then conveyed forward during the forward acceleration of the pull roll section (that is, acceleration of the sheet), the constant speed period after acceleration (during which sheet processing is performed), and the deceleration and stoppage after completion of processing. Next, the two sets of pull roll units are driven in opposite directions to pull the sheet back upstream by an amount equal to the amount of advance of the sheet sent downstream during the acceleration and deceleration/stop of the pull roll units, thereby moving the sheet to the sheet processing unit. Try to eliminate the blank space in between. This is repeated to feed sheets intermittently. The intermittent sheet feeding timing is performed by adjusting the pull roll drive timing of the drive device.

〔Example〕

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

FIG. 1 shows the configuration of a sheet rotary printing press showing an embodiment of the present invention. In FIG. 1, a roll-shaped sheet 12 is unwinded by a device 2. Printing section 10 (plate cylinder 5°, impression cylinder 6. Ink adhesion roll 7, ink reservoir 8° doctor blade 9. printing plate 14.
The configuration of the ink 21) 1 wound roll) V 12 + take-up machine 13 is the same as the conventional one.

Now, in FIG. 1, it is between the rewinding machine 2 and the printing section 10.

An infeed draw 1v15 is provided, and a pair of pull rolls 16 are provided between the infeed draw/L' 15 and the printing section 10.

Furthermore, a pair of pull rolls 17 are provided between the printing section 10 and the winding machine 18.
and a sheet feed roll 18 are provided.

Here, the pull roll 16 holds the sheet 3, stops rotating intermittently, and feeds the sheet 3 in the direction of the arrow (toward the printing section 10).

The pullrow/1z16 has a function of not only intermittently feeding the sheet 3 in the direction of the arrow, but also reversing the sheet 3 in the opposite direction of the arrow, that is, toward the infeed roll, and pulling back the sheet 8. Infeed row) v15 is also sheet 3
The sheet 3 is constantly rewound from the rolled sheet 1 and sent to the pull roll side at a preset constant speed. On the other hand, sheet feed Jiro/L/18 and printing section 10
The pull row/L'17 installed between them rotates intermittently in the forward and reverse directions at a timing and speed completely synchronized with the aforementioned pull row/L/16. The sheet feed row 1v18, like the infeed row/I/15, clamps the sheet 8 and constantly feeds the sheet to the winder 18 at a preset constant speed. The measuring car 20 is in the seat 8.

The speed, direction, and amount of progress are measured.

Next, the operation of the embodiment configured as above will be explained. The continuous sheet 3 is clamped by an infeed draw/L/15 and sent to a pull draw/L/16. Pullo/L/1
6.17 is controlled by synchronous rotation and intermittently feeds the sheet 8 in the sheet feed direction /L/18 direction, and the sheet feed direction /L'
18 constantly sends out the sheet 3 to the winder 13.

Here, each function will be explained in detail.

FIG. 2 is a speed diagram of the seat 3 when it stops running. The solid line represents the sheet speed between each pull row 1v16.17, and the one-dot line represents the speed of the sheet 8 passing through the infeed roll 15 and the sheet feed roller/I/18 section. The sheet 8 is pulled by the unwinding machine 2 by an infeed draw /l/15, and the sheet 1 in the shape of a zigzag μ is constantly fed in the direction of the pull-row zv16. As shown by the dotted line in FIG. 2, the speed of this infeed roll 15 is set to the average speed of the sheet speed that runs intermittently between each pull row /I/16. The sheet amount between 1v16 is kept constant on average. This means that the sheet behavior between the infeed draw/l/15 and the pull row Iv16 during operation is such that when the pull roll 16 is rotating, the amount of retention is small as shown by the solid line in Figure 1, and when the pull roll 16 is stopped or reversed, the amount of retention is small as shown by the dotted line. A large amount of slack means a large amount of retention. Furthermore, infeed low/L
The speed of /15 is automatically controlled so that the sheet retention amount falls within a preset upper and lower limit range. Next, the speed of the sheet feed roller /L/18 is infeed roller /1
/15 (!: Similarly, as shown by the dotted line in FIG.
The sheet amount between /17 is kept constant on average. This means that while the pull roll is rotating, the amount of retention increases as shown by the solid line in FIG. 1, and while the pull roll is stopped or reversed, the amount of retention decreases as shown by the dotted line. Note that, similarly to the infeed roll ztz 15, the speed of the sheet feed roll 18 is automatically controlled so that the sheet retention amount falls within a preset upper and lower limit range. The sheet 8 that has passed through the feed roll 18 is wound up again in a low/1/12 state by the winder 13, but the sheet speed is the same as the speed at which it passes through the feed roll 1v18. (Since the diameter of the take-up row/l/12 gradually increases, the speed of the take-up machine is automatically controlled so that the sheet speed remains constant but the rotational angular velocity of row/L'12 gradually decreases. ) In synchronization with such behavior of the sheet 8, printing is performed while the sheet 8 is traveling between each pull row 1v16.17, excluding the acceleration and deceleration periods shown in Fig. 2, that is, during a constant speed V. A printing plate 14 is attached to each plate cylinder 5 so as to perform the same operation. 9 In the case of eight-color printing (having three sets of printing units 10) as in this embodiment, the printing point A for the first color and the printing point A for the second color shown in FIG. The position of the winding roll 4 is intermittently changed as shown by the dotted line in FIG. 1 so that each sheet retention length between printing points B and C of the third color coincides with the sheet advance amount for each time. Now, the sheet progress per rotation is determined by the sheet length between each printing point A and 8, the sheet length between B and 0, and the printing plate wrapped around the plate cylinder 5 shown in FIG. 14, and furthermore, if this is shown in the velocity diagram of Fig. 2, the sheet will move for 2 hours (the time during which the sheet 3 matches the surface rotation peripheral speed of the printing plate 14). The amount of advance of the traveling seat 8, that is, the traveling speed (■) x the waiting time 2. Pull-low/l/16 and 17 are driven by separate drive motors (not shown), but the two rotations are completely synchronous rotations, and this rotation control is performed according to the speed line in Figure 2. As shown in the figure, the sheet 3 held between the pull rolls 16 and 17 from a stopped state is accelerated in the direction of the arrow shown in FIG. (As mentioned above, the speed V during this period coincides with the circumferential speed of the rotating surface of the printing plate 14, and printing is performed during this time t2.) Next, the sheet 3 is moved again during time 8. Decelerate and stop. Pullo #16.1 stopped temporarily after this.
7 is then reversely rotated for 4 hours to pull the sheet 3 back in the opposite direction, that is, in the direction opposite to the arrow direction of the sheet traveling direction shown in FIG.
Stop.

The above operation will be explained in detail in connection with the sheet 8 pull roll 16, 17 and the plate cylinder 5.

Now, the sheet 3 fed from the infeed draw/L/15 at an average speed is retained between the infeed draw/1/15 and the pull roll 16. On the other hand, the second plate cylinder 5 rotates in the direction of the arrow in FIG. 3 at a constant rotational speed equal to the surface circumferential speed V of the printing plate 14, and each pull roll 16, 17 stops, and therefore the sheet 3 between each pull roll also stops. are doing. Now 1
As shown in Fig. 3, the rotation timing of the plate cylinder 5 is such that the printing start point of the printing plate 14 reaches the position 1 from the printing point 1-A (or B, O) of each printing section, that is, the end of the printing plate reaches the position 11. When,
Each pull roll 16,17 is as shown in FIG.

Driving is started, the speed is accelerated, and after 1+ hours, when the speed ■ is reached, this speed V is maintained. On the other hand, when the pullrow/L/16.17 reaches the speed V, the printing plate 14 on the plate cylinder 5 moves to the printing point 1-A (or B) as shown in FIG.

C) is reached and printing is started. Next, seat 8 is speed■
While traveling, the printing plate 14 comes into contact with the sheet 8 as described above, printing is performed, and then the rear end of the printing plate 14 reaches the printing point as shown in FIG.

When printing is completed, in other words, when the sheet 3 completes traveling by the L dimension, each pull row/L'16 and 17 starts decelerating again and stops after 1 hour ts. During this taO period, the plate cylinder 5 continues to rotate at a constant speed and reaches a position advanced by 12 dimensions as shown in FIG. What has been stated above can be summarized as follows.

11=vxt+x' (Sheet advancement amount during acceleration from sheet stop) L = V X tz (Sheet speed ■, that is, sheet advancement amount during printing) lx = V X ts When the sheet behaves like this, the printing state on the sheet 3 is as shown in FIG. 7. , lh, there will be a blank space that is not printed.This is because, if left as is, it would not be consistent with the objective of the present invention, which is to reduce or eliminate this blank space.

As described below, the sheet 3 corresponding to the margin is pulled back in the opposite direction. Now, after printing, Pulllow/L'16,1
At the moment when the plate 7 stops (after time t8 in FIG. 2, ie, the moment when the pull roll stops), the positional relationship between the sheet 3 and the plate cylinder 5 is in the state shown in FIG. 8. The rear end 1a' of the printed portion overruns the printing point A (or B, C) by 42 dimensions and stops. If you move on to the next sheet running printing process again in this state, 1. The dimension parts are added, and a margin of II112 dimensions is created. Then, the sheet 3 is pulled back in the direction opposite to the arrow, as shown in FIG. 9, and the printing trailing edge position a' is pulled back upstream by υg1 dimension from the printing point A (or B, C), and then the pull roll is accelerated again as described above. When the printing trailing edge position 1a' reaches the printing point) A (or B, C), the printing plate front edge position for the primary printing reaches the printing point as shown in Figure 4, and there is no margin. The next print is performed. The amount of pulling back of the sheet 80 in the opposite direction of the arrow lI+112 is the time t shown in FIG.
This corresponds to the amount by which the pull row L/16°17 is driven in reverse for 44 hours to advance the sheet in the opposite direction of the arrow.

This behavior of the seat 3 is measured by the measuring wheel 20 shown in FIG. 2, which determines the direction and speed of the seat 8.

Detect and measure the amount of progress and move the plate cylinder 5. It sends a signal to control the pull-low/L46, 1γ drive motor.

Also, the sheet pull-back operation is performed when the rotational position of the first plate cylinder 5 is at the 8th rotation position.
Since the printing is performed between FIG. 9 and FIG. 9, that is, when the printing plate 14 is in the non-printing position, the 9th plate cylinder circumference πD is the actual printing length L and the sheet advancement amount during acceleration is 11. In addition to the sheet advance amount 12 at the time of deceleration and stop, the time taken to pull back the sheet is also an amount corresponding to the angle θ at which the plate cylinder rotates at a constant rotational speed in 4 hours, that is, πD×
It is assumed that θ÷360° or more.

In addition, each control condition 1, for example, t+, tz, ta,
t4゜V, etc. are set in advance or adjusted during operation to obtain the best printing accuracy, taking into account various conditions such as sheet width, tsubo weight, strength, print length, and print design. It is arbitrarily adjusted accordingly.

2. In this embodiment, a method was described in which the sheet was conveyed intermittently by being held by a pull roll, but instead of the pull roll, a suction conveyor was used as shown in Figs. 10 and 11.
It is also possible to use a method of holding the sheet by adsorbing the sheet to the belt surface or a method of adsorbing the sheet to the low μ surface using a sacsilane roll to provide the holding force necessary for feeding.

〔Effect of the invention〕

As described above, according to the present invention, the intermittent feed length can be changed by adjusting the intermittent drive timing of the pull roll section, so there is no need to prepare extra replacement parts, which is economical.

Intermittent feed length can be easily changed, reducing interruption time in sheet processing. In addition, the distance between the processed parts is corrected by driving the pull row 2 part in the front and back direction within one feed cycle, that is, by feeding the sheet in the advancing direction and then pulling it back in the opposite direction to the advancing direction. There is no need to instantaneously accelerate the current seat or instantaneously stop the traveling seat, and the amount of slip changes due to the above operations.

There is no stretching, flapping, meandering, etc. of the sheet due to sudden tensile force applied to the sheet, and the accuracy of intermittent feeding is improved.

[Brief explanation of the drawing]

1 to 9 show one embodiment of the present invention, FIG. 1 is a side sectional view, FIG. 2 is an explanatory view showing the operating state, and FIGS. 3 to 6 are front views of the seat of this embodiment. FIG. 7 is a plan view illustrating the state of printing on a sheet; FIGS. 8 and 9 are side views illustrating the state of the printing section when the sheet is pulled back; FIG. , FIG. 10 and FIG. 11 are side views showing other embodiments of the pull roll section, FIG. 12 is a side sectional view showing a conventional continuous sheet rotary printing press, and FIG. 18 is a side view showing another embodiment of the pull roll section, and FIG. Detailed drawing of, No. 14
1 and 15 are side views showing different examples of conventional pull roll sections, respectively. 8...Sheet, 10...Printing department, 16.17...
・Pullow bucket・Y

Claims (1)

[Claims] In an intermittent feeding device for continuous sheets that runs a continuous sheet and processes the same sheet along the way, a pair of pull roll sections are provided on the upstream and downstream sides of the processing section, respectively, to hold the sheet and feed it back and forth. 1. An intermittent feeding device for continuous sheets, comprising: a drive device that intermittently drives a pull roll portion in the front and back direction at synchronized timing.