JPH04332846A - Measuring method of young's modulus and regulating method of tension in printer - Google Patents

Abstract

PURPOSE:To improve machining precision at the time of machining of a punch hole by measuring a Young's modulus of a web in the course of running and by making use of the measured modulus for regulation of tension in a printer equipped with a punch hole machining part. CONSTITUTION:A web 2 is passed on feed rolls 3 and 4 of speeds V1 and V2, tensions T1 and T2 before and behind the feed roll 3 are measured and a Young' s modulus E1 of the before printing is computed from measured values of the speed and the tensions thereof. The web after printing is passed likewise on feed rolls 8 and 13 of speeds V3 and V5, tensions T4 and T5 before and behind the feed roll 8 are measured, and a Young's modulus E2 of the web after printing is computed from measured values of the speed and the tensions thereof. A target value of the tension T5 of the web in a machining part 12 is set by the two Young's modulus E1 and E2 and the tension is regulated so that the target value be attained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the Young's modulus of a web running in a printing press and a method for adjusting the tension of the web in the printing press. Young's modulus measurement method and tension suitable for use in printing machines that have a processing section behind the printing section that performs hole drilling at a constant pitch in the longitudinal direction or perforations (horizontal perforations) at a constant pitch Regarding the adjustment method.

0002

2. Description of the Related Art Conventionally, as shown in FIG. 2, a form printing machine for office use has an infeed section 5 equipped with feed rolls 3 and 4 for feeding out a web 2 from a take-up 1, and a predetermined printing process on the web 2. A printing section 7 equipped with a printing unit 6 for printing, a first outfeed section 9 having a first feed roll 8 that conveys the printed web downstream, and holes (marginal punch holes) at a constant pitch formed in the web 2. A perforation cylinder 10 for forming horizontal perforations at a constant pitch on a web and a perforation cylinder 1 for forming horizontal perforations at a constant pitch on a web.
A second outfeed section 15 is provided with a second feed roll 13 for conveying the web 2 and a winder for winding the web 2 onto a winder 14. 2 is pulled out from the winding 1 by feed rolls 3 and 4, and after predetermined printing is performed by printing units 6 and 6, holes are punched, perforated, etc. are performed in a processing section 12, and the second outfeed is It was supposed to be wound up in section 15. Also known is a structure in which it is folded in a zigzag pattern instead of being rolled up. In such a form printing machine, feed rolls 3, 4, a first feed roll 8,
The second feed rolls 13 are driven synchronously, and the tension of the web at each portion is adjusted by the difference in circumferential speed.

0003

However, such conventional printing machines have a problem with the pitch accuracy of holes, perforations, etc. formed in the processing section. That is, the processing section 12
In this example, the web 2 passing through the web 2 is drilled or horizontally perforated at a constant pitch in the longitudinal direction, but the web 2 passing through the processing section 12 is stretched by the tension. Therefore, when the web shrinks after processing, the amount of shrinkage varies depending on the web, and as a result, the desired pitch accuracy may not be obtained.

Conventionally, an operator measures the pitch deviation and sets the tension in the printing section and processing section by taking into account the amount of deviation, web thickness, width, paper quality, etc., but this method is difficult to achieve the desired result. There were problems such as not being able to obtain pitch accuracy, resulting in a large amount of wasted paper, and requiring skill to perform the work.

[0005] As a result of studies to solve the conventional problems, the present inventor found that the Young's modulus of the web changes due to printing, and the elongation of the web changes due to the change in Young's modulus, making it difficult to set the tension. In addition, if the Young's modulus in the printing part and the processing part can be measured, it is possible to set the tension so that the elongation in the printing part and the processing part are equal based on the Young's modulus, and thereby, It was discovered that the pitch accuracy of punch holes and horizontal sewing machines can be improved.

The present invention was made based on this knowledge, and an object of the present invention is to provide a method for measuring the Young's modulus of a web running in a printing press.

Another object of the present invention is to provide a tension adjustment method for setting the tension of a web so as to improve the pitch accuracy of holes, perforations, etc. processed by a processing section.

[0008]

[Means for Solving the Problems] The present invention provides a printing press in which a web having a cross-sectional area A is run through a roll having a circumferential speed of V1 and a roll having a circumferential speed of V2 positioned downstream thereof.
At that time, the web tension T1 in front of the upstream roll and the web tension T2 between the two rolls are measured, and a value (EA) proportional to the Young's modulus E of the web is determined by the following formula. The main purpose of this paper is how to measure Young's modulus in printing presses.

Further, the present invention provides a printing machine having a printing section for printing on a web and a processing section for forming holes, perforations, etc. at a constant pitch in the longitudinal direction of the web after printing. A printing machine characterized in that the Young's modulus E1 of the web at and the Young's modulus E2 of the web behind the printing section are measured by the above method, and the web tension in the processing section is set based on the Young's moduli E1 and E2. The gist is the tension adjustment method.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to the drawings. FIG. 1 schematically shows a printing press used to carry out the method of the present invention, and the same parts as those in the conventional printing press shown in FIG. In the printing machine shown in FIG. 1, a speed adjustable first motor 16 is connected to the feed rolls 3 and 4, and a decelerator 17 is arranged between the feed rolls 3 and 4 to give a slight speed difference between the two. has been done. A second motor 18 is connected to the printing units 6 , 6 via a speed reducer 19 . A third motor 20 and a fourth motor 21 whose speeds are adjustable are also connected to the first feed roll 8 and the second feed roll 13, respectively. Furthermore, the feed roll 3 and each motor 16, 18,
20, 21 have speed detectors 23, 24, 25, 26,
27 is connected to detect the speed of the web conveyed by the corresponding roll or printing unit. Tension detectors 29A, 29B, and 29C are installed on the running path of the web 2 to measure the tension of the web at each part.
, 29D, and 29E are arranged.

The control device for controlling each motor of the printing press has a keyboard 31 for input and a control unit 32, and output signals from each speed detector and tension detector are sent to the control unit 32. It is now entered into This control unit 32 has the functions shown in the block diagram in the drawings. These functions will be described in the description of the operation below.

Next, the operation of the printing press having the above configuration will be explained. In addition, in FIG. 1 and the following explanation, V1,
V2, V3, V4, V5 are the web speeds, T
1 , T2 , T3 , T4 , and T5 indicate web tension.

Table 1 storage section 3 of control unit 32
5, item data (paper thickness, paper width, basis weight, paper quality), experience value data, etc. for setting the tension T2 are input in advance from the keyboard 31, and data as shown in Table 1 is stored.

[0014]

[Table 1]

Table 1 shows part of the data stored in the Table 1 storage section 35, and stores T2 tension setting values T2' for various webs. This T2 tension setting value T2' is obtained by calculation from an empirical value and the empirical value, and the calculation will be explained below. In Table 1, the data for high-quality paper and paper thickness 60 mm are obtained from empirical values, and using this as a standard, paper thickness 1
Values for 00mm and 200mm have been calculated. That is, the paper thickness is 60 mm, the paper width is 445 mm,
In order to perform good printing on a web with a basis weight of 52.3 g/m2, it has been confirmed from experience that T2 = 12.7 kg, and this value is the reference value tension Z0 that is the basis of calculation. Become. Further, the value of the cross-sectional area A of this 60 mm paper web web of 26.7 becomes the reference value A0, and the value of the unit thickness basis weight α (details will be described later) of 1.96 becomes the reference value α0. If the suitable tension T2 for a web of a certain cross-sectional area is known, and if the ease of stretching of the web is the same for webs of different paper widths and paper thicknesses, then the tension T2 can be determined by A value proportional to the area may be used. According to this idea, the calculated tension Z in Table 1 is calculated in proportion to the cross-sectional area of the web, based on the reference tension Z0 (=12.7) obtained from empirical values without considering the ease of stretching of the web. A suitable value for the tension T2 was calculated as follows, and the calculation formula is as follows. Z=Z0 ×A/A0 =Z0 ×n

However, if the elongation of the webs differs, it is not preferable to use the calculated tension Z in Table 1 as is as the T2 tension setting value, and for webs that are easy to elongate, it is necessary to correct the tension to reduce it. be. In general, webs tend to stretch easily when they have a small unit thickness and a small weight per unit area (unit thickness basis weight α in Table 1).
The calculated tension Z obtained by calculation is calculated based on this unit thickness basis weight α
It is necessary to correct it by The T2 tension setting value T2' in Table 1 is a value obtained by correcting the calculated tension Z by the unit thickness basis weight α, and its calculation formula is expressed as T2'=Z×α/α0=Z×m. Good printing can be achieved by adjusting the web tension T2 at the position where the web enters the printing unit so as to achieve this tension setting value T2'. In the Table 1 storage unit 35, such a tension setting value T2' is determined and stored from empirical values for various webs or by calculation based thereon.

Initial line operating conditions are also input into the control unit 32 in advance.

When starting the operation of the printing press, the operator first inputs the paper thickness, paper width, basis weight, and paper quality using the keyboard 31. The third calculation section 36 of the control unit 32 is
Based on the input conditions, a T2 tension setting value T2' suitable for the web is determined from Table 1. If there is no data corresponding to Table 1, the T2 tension setting value T2' is calculated using the formula shown in Table 1.

Next, when the printing press starts operating, the motors 16, 18, 20, and 21 are controlled by the first motor control section 38, the second motor control section (reference speed control section) 39, and the third motor control section, respectively. The web is controlled by a fourth motor control section 40 and a fourth motor control section 41 to run the web and perform printing and processing. At this time, the second motor control section 39, the third motor control section 40
, the fourth motor control section 41 respectively controls the corresponding motor 18.
, 20, 21 are controlled according to initial line operating conditions. On the other hand, the first motor control unit 38 controls the first motor 16 to vary the speed V2 and control the web tension so that the web tension T2 becomes the above-mentioned T2 tension setting value T2'.

After the web 2 starts running, the tension detectors 29A to 29E arranged at each position measure the web tension, and the tensions T0 and T1 are inputted to the first calculation section 43. Further, the speed detectors 23 to 27 measure the web speed of each section, and among them, the speeds V1 and V2 are also input to the first calculation section 43.

By the way, generally speaking, the speed of the web is V1
When traveling through a roll located downstream of V2 and a roll located downstream thereof, the web tension in front of the upstream roll is T0, and the web tension between the two rolls is T1. , the web cross-sectional area A, and the web Young's modulus E have the following relationship.

Therefore, if the Young's modulus in the infeed section 5 of the printing press in FIG. 1 is E1, the speeds of the first feed roll 3 and the second feed roll 4 are V1 and V2.
, the tension T0 and T1 before and after the first feed roll 3, the web cross-sectional area A, and the web Young's modulus E1.
Similar to equation 1), there is the following relationship. The first calculation unit 43 calculates the tension T0, T1
, speeds V1 and V2 are input, and the above equation (2) is calculated. As a result, the web (
A value proportional to Young's modulus E1 (web before printing) (E1
A) is required. The obtained value is output to the divider 45.

On the other hand, the first feed roll 8 downstream of the printing section 7
, the speeds V4, V5 of the second feed roll 13, and the tensions T4, T5 before and after the first feed roll 8 are input to the second calculation unit 46. The above-mentioned ( The same relationship as in equation 1) holds true, and therefore the following equation holds. The second calculation unit 46 calculates the input tension T4
, T5, speed V4, V5 to calculate equation (3),
A value (E2 A) proportional to the Young's modulus E2 of the web (web after printing) in the processing section 12 is obtained, and the value is output to the divider 45.

The divider 45 divides the input values E1A and E2
From A, calculate. This value E3 indicates the rate at which the Young's modulus changes due to printing, and if there is no change in paper quality due to ink, moisture, etc., E3 =1.

The value E3 obtained by the divider 45 is calculated by the multiplier 48.
is input. At the same time, the multiplier 48
Input the T2 tension setting value T2' output from 6,
From both input values, E3 ×T2 ′=T5 ′
(5) is calculated, and the obtained value T5' is output to the fourth motor control section 41 as the T5 tension target value.

The fourth motor control unit 41 controls the web tension T5 in front of the second feed roll 13 to the above-mentioned target value T5'.
The fourth motor 21 is controlled to vary the speed V5 so that the tension of the web is controlled.

As described above, before the start of operation, the T2 tension setting value T2' is determined, and at the beginning of the start of operation, the Young's modulus E1, E2 (strictly speaking, E1 A, E2
A) is measured, and the target tension value T5' is determined from that value. After that, the web tensions T2 and T5 are controlled to the set value T2' and target value T5', and printing and processing are performed. be exposed. Thereby, the amount of elongation of the web 2 in the printing section 7 and the amount of elongation in the processing section 12 can be made approximately equal, and highly accurate processing can be performed. Note that the second motor 18 and the third motor 20 continue to be operated under the initial line operating conditions by the second motor control device 39 and the third motor control device 40, respectively.

Next, as described above, the web tensions T2 and T
The reason why the amount of elongation of the web 2 in the printing section 7 and the amount of elongation in the processing section 12 are approximately equal when the amount of elongation of the web 2 is controlled to be the set value T2' and the target value T5' will be briefly explained. Web tension T3 in printing section 7
is approximately equal to the previous web tension T2, and the web tension T2 is controlled to a set value T2',
Furthermore, since its Young's modulus is E1, the elongation δ1 per unit length of the web in the printing section 7 is δ1 = T2 /E1 = T2 '/E1
(6) becomes. On the other hand, the tension in the processing section 12 is approximately equal to the web tension T5 downstream thereof, and the web tension T5 is controlled to the target value T5', and its Young's modulus is E2, so the web tension in the processing section 12 is The elongation δ2 per unit length is δ2 = T5 /E2 = T5 '/E2
(7). Substituting equations (4) and (5) above into equation (7), δ2 = E3 ×T2 ′/E2 = E3 ×T2 ′/E1 ×E3 = T2 ′/E1
(8) From equations (6) and (8), δ1 = δ2
becomes. That is, the amount of elongation of the web 2 in the printing section 7 and the amount of elongation in the processing section 12 are approximately equal.

In the above explanation, it is assumed that the web tension T3 in the printing section 7 is approximately equal to the previous web tension T2, and that the tension in the processing section 12 is approximately equal to the web tension T5 downstream thereof. Perhaps because there are some differences in the target value T
5' and control the web tension T5 so as to match the target value, the processing accuracy may be slightly degraded. In that case, T5 ′=E3 ×T2 ′×C (9
) is preferable to calculate the target value T5'. Here, C is a correction coefficient, and this correction coefficient C is determined empirically.

In the above embodiment, Young's modulus E1 and E2 are measured at the start of operation of the printing press, and T is determined from the Young's modulus.
The target value of T5 is calculated, and the tension is then controlled to reach the target value.
The calculation of T5' may be performed not only at the start of operation of the printing press but also at appropriate intervals during operation, and if the obtained target value T5' is different, a new target value may be used.

[0031] The web tensions T2 and T5 are set to their set values T.
2', control and operate so that the target value T5' is achieved,
After confirming that good printing and processing have been performed, by pressing the learning instruction button on the keyboard 31, the set value T2' at that time is input into the Table 1 storage section 35. Also,
If the machining accuracy is poor, slightly modify the set value T2' and operate, and even if a good result is obtained, by pressing the learning instruction button on the keyboard 31, the current set value T2 can be changed.
' is stored in the Table 1 storage unit 35. In this way,
A good T2 tension setting T2' based on experience can be written into the Table 1 storage.

In the above embodiment, the control unit 32 is provided with a calculation function, and the tension setting value T2 is
' and T5 The tension target value T5' is automatically calculated by the control unit 32 and the tension is controlled accordingly, but the present invention is not limited to this case. It is also possible to provide only a display function and a function to control the tensions T2 and T5, and allow the operator to calculate the T2 tension set value T2' and the T5 tension target value T5'. That is, the operator first obtains the T2 tension setting value T2' from the web conditions, inputs it into the printing machine, operates the printing machine, and then calculates the T5 tension target value T5' from the displayed Young's moduli E1 and E2. It is also possible to calculate T5, input it into the printing press, and then operate the printing press so that the tension target value T5' is achieved. Furthermore, in the embodiment described above, the speeds of the first motor 16 and the second motor 20 are controlled by changing the speeds of the first motor 16 and the second motor 20 so that the web tensions T2 and T5 become the predetermined T2 tension set value T2' and T5 tension target value T5', respectively. However, the tension control does not necessarily need to be performed accurately all the time, and after determining the T2 tension set value T2' and T5 tension target value T5', the T2 tension and T5
The tension is set at each set value T2' and target value T5'
Automatically or manually adjust the speed of the motors 16, 20 so that
You may drive.

In the above embodiment, T2 tension setting value T2
Although a case has been described in which E1 is determined based on Table 1, it is also possible to determine it using the measured Young's modulus E1 as a reference instead. In other words, it is preferable to adjust the tension in the printing section so that the elongation is constant regardless of the type of web, so calculate the tension value that will make the elongation constant from the Young's modulus E1, and use that tension value as T2. Tension setting value T2'
May be used as

In the printing press shown in FIG. 1, independent variable speed motors 16, 17, 20, 2 are used to drive each roll.
1 is used, however, instead of this, it is also possible to use a line shaft driven by a common main motor as in a conventional printing press. In that case, a continuously variable transmission may be interposed between the line shaft and the second feed roll 4 and between the line shaft and the second feed roll 13, thereby making it possible to adjust or control the speeds V2 and V5. Bye.

[0035]

As described above, according to the method for measuring Young's modulus of the present invention, a web is run through a roll having a circumferential speed of V1 and a roll having a circumferential speed of V2 located downstream thereof, and By measuring the web tension T1 in front of the side roll and the web tension T2 between the two rolls, and calculating from the obtained values, the running web (cross section A) is calculated.
It is possible to measure a value proportional to Young's modulus E (EA), and has the effect that, for example, the Young's modulus of a web before printing or a web after printing in a printing machine can be measured.

Further, according to the tension adjustment method of the present invention, in a printing machine provided with a processing section behind the printing section for forming holes, perforations, etc. at a constant pitch in the longitudinal direction of the web after printing, the printing section By measuring the Young's modulus E1 of the web in front of the web and the Young's modulus E2 of the web behind the printing section, and setting the web tension in the processing section based on the Young's moduli E1 and E2, the elongation in the printing section and the processing section can be reduced. can be kept almost constant, and has the effect of increasing the pitch accuracy of holes, perforations, etc. machined by the processing section.

[Brief explanation of drawings]

FIG. 1: Schematic diagram of a printing press and its control device used to carry out the method of the present invention

[Figure 2] Schematic side view of a conventional printing press

[Explanation of symbols]

1 Winding 2. Web 3 First feed roll 4 Second feed roll 5 Infeed section 6 Printing unit 7 Printing Department 8 First feed roll 9 First outfeed section 12 Processing section 13 Second feed roll 14 Winding 15 Second outfeed section 16 First motor 17 Second motor 20 Third motor 21 Fourth motor 24-27 Speed detector 29A-29E Tension detector 31 Keyboard 32 Control unit

Claims (2)

[Claims] Claim 1: In a printing press, a web with a cross-sectional area A is moved between a roll having a peripheral speed V1 and a roll located downstream thereof having a peripheral speed V2.
The web tension T1 in front of the upstream roll and the web tension T2 between the two rolls are measured, and the value proportional to the Young's modulus E of the web (EA) is calculated as follows: A method for measuring Young's modulus in a printing press, characterized in that the Young's modulus is determined by the formula. Claim 2: A printing unit that performs printing on the web;
In a printing machine that has a processing section that forms holes, perforations, etc. at a constant pitch in the longitudinal direction of the web after printing, the Young's modulus E1 of the web in front of the printing section and the Young's modulus E2 of the web behind the printing section are calculated. A method for adjusting tension in a printing press, comprising measuring by the method according to claim 1 and setting web tension in a processing section based on the Young's moduli E1 and E2.