=Paper= {{Paper |id=Vol-2533/paper27 |storemode=property |title=Modeling of the Ink Printing System and Improving the Accuracy of Its Adjustment Based on the Obtained Three-Dimensional Imprints |pdfUrl=https://ceur-ws.org/Vol-2533/paper27.pdf |volume=Vol-2533 |authors=Mykhailo Verkhola,Ulyana Panovyk,Ihor Huk,Myron Kalytka |dblpUrl=https://dblp.org/rec/conf/dcsmart/VerkholaPHK19 }} ==Modeling of the Ink Printing System and Improving the Accuracy of Its Adjustment Based on the Obtained Three-Dimensional Imprints== https://ceur-ws.org/Vol-2533/paper27.pdf
    Modeling of the Ink Printing System and Improving the
     Accuracy of Its Adjustment Based on the Obtained
                 Three-Dimensional Imprints

       Mykhailo Verkhola1[0000-0001-6135-6439], Ulyana Panovyk1[0000-0002-9663-4328],

                Ihor Huk 1[0000-0002-0815-3496], Myron Kalytka 1[0000-0001-7814-7211]
        1
            Ukrainian Academy of Printing, Pid Holoskom, St., 19, 79020 Lviv, Ukraine
                              ulianapanovuk@gmail.com



       Abstract. A mathematical model of the ink printing system of the offset ma-
       chine is developed, which reflects the processes of ink distributing and transfer
       in the circular and axial directions. The model takes into account the operation
       modes of the ink feeder subsystem and the oscillator cylinder and the function-
       ing of all other ink printing system elements. The model reflects the process of
       ink distribution and movement by surfaces of rollers and cylinders in three co-
       ordinates, that is, in three-dimensional space. Based on the mathematical model
       and the functional scheme, a simulator of the ink printing system was construct-
       ed, which reproduces the process of imprints replication and allows changing
       the parameters of the oscillator cylinder operation modes and the ink feeder
       subsystem. Based on the balance of ink supply and the expense, the reliability
       of the developed model of the ink printing system was verified. The simulation
       results in three-dimensional images of the imprints for different axial stroke
       values of the oscillator cylinder. The influence of the oscillator cylinder opera-
       tion mode on the uniformity of the ink thickness on the imprints is conducted.
       The ink relief’s analysis for different axial stroke values of the oscillator cylin-
       der is carried out. The advantages of mathematical representation of ink distri-
       bution and transfer processes in three-dimensional coordinates over two-
       dimensional models are substantiated. Based on the obtained ink thicknesses
       profiles in different zones of three-dimensional imprints, the need for more ac-
       curate adjustment of the ink printing system was established. And this can only
       be done based on information obtained from 3-D images of imprints.

       Keywords: 3-D Images of Imprints, Ink Printing System, Ink Feeder Subsys-
       tem, Oscillator Cylinder, Printing Form, Ink Thickness.


1      Introduction

1.1    Formulation of the problem
The ink transfer at the output of the ink printing system is carried out only on the
printing elements of the form, so on the form rollers are formed corresponding ink

Copyright © 2019 for this paper by its authors. Use permitted under Creative Commons License
Attribution 4.0 International (CC BY 4.0)
2019 DCSMart Workshop.
reliefs. To smooth the ink thickness on the surface of the form rollers are used oscilla-
tor rollers, which simultaneously with the rotational motion carry out an axial recipro-
cating movement. The effectiveness of ink rolling depends on the initial phase of the
motion trajectory and the magnitude of the oscillator's axial stroke, as well as their
number and location in the ink printing system [1]. Consequently, the quality of the
printed products depends significantly on the parameters and topology of the ink
printing system.
    Increasing requirements for print quality are pushing printing machine manufactur-
ers to improve their ink printing systems. The solution to this problem is possible only
if the theoretical principles of analysis and synthesis of ink printing systems are fur-
ther developed. The ink transfer from the ink fountain to the imprints is accompanied
by the sequential imposition (formation) and separation (distribution) of ink at the
contact points of the ink printing system elements [2]. The perturbations that occur in
the ink printing systems from the action of the ink feeder subsystem, the oscillator
cylinders and the printing form cause fluctuations in the ink thickness at the output of
the ink printing system. From the size and uniformity of the ink thickness on the im-
prints directly depends on their quality. Therefore, determining the ink thickness layer
at any point in the imprint is an important task.


1.2    Analysis of literary data and problem statement

The existing methods and means of determining the ink layer thickness on the im-
prints through optical density give only integral information about the ink thickness,
so this problem can only be done by computer simulation. And this requires the de-
velopment of mathematical models that must accurately describe the process of ink
distribution and transfer, taking into account the operation modes of the ink fountain
subsystem and oscillator cylinders.
    The work [3] is devoted to the ink printing system research of different structures.
A mathematical model with a discrete and continuous ink supply system has been
developed. As a result of the simulation, it is established that the ink supply system,
the parameters of the oscillator cylinder, filling the form with printing elements have
a significant impact on the dynamic properties. It was found that with increasing the
frequency of the ink supply, the time of the system to enter the operating mode de-
creases, and accordingly the costs of the ink decrease. In [4], the study results of an
offset printing ink printing system dynamic properties are presented. Computer simu-
lation investigated the influence of oscillator cylinders and printing form on the dura-
tion of the ink printing system set mode. It is established that in the absence of the
axial stroke of the oscillator cylinders, the time of the transition process is inversely
proportional to the density of the form's printing elements filling. Article [5] investi-
gates the distribution of ink supplied from the ink feeder device to the printed im-
prints. It is established that part of the ink, which should come in zones with higher
coefficients of the printing elements form's filling, is transferred to zones with the
fewer coefficients of the printing elements form's filling. Therefore, the change in the
ink thickness on the imprint due to the redistribution between the zones with different
intensities of printing elements form's filling should be compensated by the input task.
In [6], to improve the properties of the ink printing system, the structural elements of
the ink feeder device used in the offset printing machine were analyzed. A computer
simulation and printing experiment were performed to test the dynamic features of the
printing system. The research showed that the ink transfer from the inking feeder
device to the printing imprints is affected by the rotation of the vibrator roller, the
duration of its cycle and the plate cylinder gap. As the oscillation of the vibrator roll-
er, the axial stroke of the oscillator cylinders and the plate cylinder gap cannot be
eliminated in a sheet printing machine, therefore it is necessary to carry out a study of
the imprint's quality taking into account the effect of these negative factors. In [7], a
neural network model of an ink printing system was proposed, with the help of which
a research of the distribution process and ink transfer from the input of the system to
imprints was carried out. The neural model is built based on a three-layer perceptron
of direct propagation, so it cannot take into account the circulation of back ink flows,
nor does it take into account the action of the feeder device and the plate cylinder gap.
   In all the publications discussed above, the average zonal values of the ink thick-
nesses within individual zones are used for research and analysis of the ink printing
systems. Since the width of the ink supply zone in different offset machines is differ-
ent and maybe several centimeters, and the length of the form is several tens of cen-
timeters, the ink thickness on the imprint within one particular zone may vary signifi-
cantly. Therefore, to research the process of ink transfer and the quality of imprints, it
is necessary to develop mathematical models that would detail reflect printed imprints
in three-dimensional space.


2      Materials and methods

2.1    The operation algorithm of the ink printing system
We will demonstrate the solution of this problem on the example of an ink printing
system, the functional scheme of which is presented in Fig. 1. Unit 1 of the input zon-
al task is a set of regulators that can be driven by cam mechanisms or stepper motors.
The number of such regulators corresponds to the number of zones for regulating the
ink supply. Adjustment of the ink supply is made by changing the size of the gap
between the fountain blade and the fountain roller. The composition of the ink feeder
subsystem (block 2) in addition to the fountain cylinder also includes a ductor roll-
er [8]. The fountain cylinder has a rotating motion, and the ductor roller in addition to
the rotating one is also oscillating. The ductor roller transfers ink from the fountain
cylinder obtained during its rotation in contact with the fountain cylinder and trans-
mits it to the subsystem (block 3) during joint movement with the first distributing
roller of this subsystem. The ink distributing and transfer subsystem includes a group
of rollers with a rubber surface, which are driven in a friction-rotating manner in a
circular direction. In this subsystem, ink during transferred from block 2 to block 4 is
superimposed and splits at the contact points of the rollers, forming direct and reverse
ink flows circulating in a circular direction. The subsystem of ink distributing and
transfer in an axial direction (block 4) is implemented based on oscillator cylinders,
which are driven by the main electric drive of the ink printing system. The oscillator
cylinders simultaneously with the rotary motion carry out also an axial reciprocating
movement. This subsystem makes it possible to adjust the initial phase and the ampli-
tude of the axial movement of the oscillator cylinders. The oscillator cylinders in
contact with the rollers of the ink distributing and accumulation subsystem (block 5)
align an ink in the axial direction on the surface of the form rollers. The form rollers,
in contact with the printing form (block 6), transfer the ink to the surface of the print-
ing elements. The subsystem of ink transferring from printing form to paper (block 6)
includes a form cylinder with a printing form fixed to its surface and an offset cylin-
der, which are rotated from the main drive of the ink printing system. The ink from
the surface of the printing form is transmitted through the offset cylinder to the paper,
forming the imprints. Since all the elements of the printing system have rotational
motion, the part of ink that is transmitted from the ink feeder subsystem to the im-
prints will be rotated back to the ink fountain.



                hd1 (z)       hd2 (z)        hd3 (z)                                          hdn (z)



            Pd j (z), Rdj (z), Pn (z), Pn (z), Pn* (z), Rn* (z), Pnd ( z ), P1n ( z ), Rn1 ( z ), Rdn
                                                                                                          
                                                                                                             ( z)



                     Pi b1 (z), Rib1 (z), , Pi b k (z), Rib k (z), , Pi b nk (z), Rib nk (z)



                                                       Pmb1 qi (z), Rmb 1 qi (z)



                                                            Pmbi1 (z), Rmb1i (z)



                                    Pf ( z ), Rf ( z ), Pof ( z ), Rof ( z ), Pc ( z )



               hcb 1 (z)      hcb  2 (z)                          hcb  k (z)                         hcb  nk (z)



                            Fig. 1. Functional scheme of the ink printing system.


2.2    Mathematical model of the ink printing system with a three-dimensional
       reflection of imprints
When constructing the model, we accept the following assumptions: the diameters of
the ink rollers and cylinders are different; the linear speeds of the rollers, the oscillator
cylinder, plate cylinder with the form fixed to its surface and the offset cylinders are
equal; the axial stroke value of the oscillator cylinder can be set arbitrarily; no-slip at
the points of the ink printing system elements contact; the ink flow thickness supplied
to the inlet of the ink printing system within a separate regulation zone is constant; the
surfaces of the ink rollers, the oscillator cylinder, the plate and the offset cylinder are
conditionally divided in a circular direction into m zones, which are additionally di-
vided into b microflows within a separate j-th zone; the ink microflows thickness on
the surface of the ink printing system elements as it moves between the points of their
contacts is constant.
   Based on works [9, 10] and the operation algorithm of the ink printing system, the
functional scheme of which is presented in Fig. 1, we form a system of equations,
which describes the process of ink circular and axial distribution and its transfer to the
printing form and further through the offset cylinder on paper.
   For the first microflow of the first zone:
          xnb 1 ( z )  Pgb 1 ( z ) Pdb 1 ( z )hdb 1 ( z )  ldn
                                                                  b 1
                                                                       ( z );
             b 1
            hnd   ( z )  Pnb 1 ( z ) x1b 1 ( z ); ldb 1 ( z )  Rdb 1 ( z ) xnb 1 ( z );
             b 1
            ldn   ( z )  Rnb 1 ( z ) Pgb 1 ( z )hnd
                                                    b 1            b 1
                                                         ( z )  ( Rdn   ( z )  Rnb 1 ( z ) Rnb11 ( z ) Ppb 1 ( z ))lnb11 ( z );
            h1bn1 ( z )  ( P1bn1 ( z )  Pn*( b 1) ( z ) Pndb1 ( z) Pgb 1 ( z ))hnd
                                                                                       b 1
                                                                                            ( z )  Pn*(b 1) ( z ) Ppb 1 ( z )lnb11 ( z);
            x1b 1 ( z )  h1bn1 ( z )  l1b 1 ( z ); lnb11 ( z )  Rn*(b 1) ( z ) x1b 1 ( z );
           h1b 1 ( z )  P1b 1 ( z ) x1b 1 ( z ); x2b 1 ( z )  h1b 1 ( z )  l2b 1 ( z );
           ...........................................................
           hmb 12 ( z )  Pmb21 ( z ) xmb 12 ( z ); lmb 13 ( z )  Rmb 13 ( z ) xmb 12 ( z );
            xmb 11 g (z)   g r (z) ( z )  hmb 12 ( z )  lmb 11 g (z)   g r (z) ( z );
              b 1 g (z)   g p (z)              b 1 g p (z)
            hm 1                       ( z )  Pm 1               ( z ) xmb 11 g (z) ( z ); lmb 12 ( z )  Rmb 12 ( z ) xmb 11 ( z );
              b 1 g (z)   g p (z)              b 1 g (z)  g p (z)
            xm                          ( z )  hm 1                       ( z )  lmb 1 ( z );
            hmb 1 ( z )  Pmb 1 ( z ) xmb 1 ( z ); lmb 11 g (z)   gr (z) ( z )  Rmb 11  gr (z) ( z ) xmb 1 g (z) ( z );
            xbf 1 ( z )  hmb 1 ( z )  l bf 1 ( z );
            hbf 1 ( z )  Pfb 1 ( z ) xbf 1 ( z ); lmb 1 ( z )  Rmb 1 ( z ) xbf 1 ( z );
            xofb 1 ( z )  hbf 1 ( z )  lofb 1 ( z );
            hofb 1 ( z )  Pofb 1 ( z ) xofb 1 ( z );
            xсb 1 ( z )  hofb 1 ( z ); lofb 1 ( z )  Rofb 1 ( z ) xсb 1 ( z );
        hcb 1 ( z )  Pcb 1 ( z ) xcb 1 ( z );
  For k microflow of the first zone:
        xnb  k ( z )  Pgb  k ( z ) Pdb  k ( z )hdb  k ( z )  ldn
                                                                    bk
                                                                        ( z );
             bk
            hnd  ( z )  Pnb  k ( z ) x1b  k ( z ); ldb  k ( z )  Rdb  k ( z ) xnb  k ( z);
             bk
            ldn  ( z )  Rnb  k ( z ) Pgb  k ( z ) hnd
                                                      bk            b k
                                                          ( z )  ( Rdn   ( z )  Rnb  k ( z ) Rnb1 k ( z ) Ppb  k ( z ))lnb1 k ( z );
            h1bn k ( z )  ( P1bn k ( z )  Pn*(b  k ) ( z ) Pndb  k ( z ) Pgb  k ( z ))hndb  k ( z )  Pn*(b  k ) ( z ) Ppb  k ( z )lnb1 k ( z );
             x1b  k ( z )  h1bn k ( z )  l1b  k ( z ); lnb1 k ( z )  Rn*(b  k ) ( z ) x1b  k ( z );
            h1b  k ( z )  P1b  k ( z ) x1b  k ( z ); x2b  k ( z )  h1b  k ( z )  l2b  k ( z );
            ...........................................................
              b  k  g (z)   g p (z)          b  k  g(z)   g p (z)
            xm                          ( z )  hm 1                     ( z )  lmb  k ( z );
             hmb  k ( z )  Pmb  k ( z ) xmb  k ( z ); lmb 1k  g (z)  gr (z) ( z )  Rmb 1k  gr (z) ( z ) xmb  k  g (z) ( z );
             x bf  k ( z )  hmb  k ( z )  l bf  k ( z );
             hbf  k ( z )  Pfb  k ( z ) xbf  k ( z ); lmb  k ( z )  Rmb  k ( z ) xbf  k ( z );
             xofb  k ( z )  hbf  k ( z )  lofb  k ( z );
             hofb  k ( z )  Pofb  k ( z ) xofb  k ( z );
             xсb  k ( z )  hofb  k ( z ); lofb  k ( z )  Rofb  k ( z ) xсb  k ( z );
         hсb  k ( z )  Pсb  k ( z ) xсb  k ( z );
   For k microflow of n zone:
         xnb  nk ( z )  Pgb  nk ( z ) Pdb  nk ( z)hdb  nk ( z )  ldn
                                                                        b  nk
                                                                               ( z );
              b  nk
             hnd     ( z )  Pnb  nk ( z ) x1b  nk ( z ); ldb  nk ( z )  Rdb  nk ( z ) xnb  nk ( z );
             ldnbnk ( z)  Rnbnk ( z)Pgbnk (z)hndbnk ( z)  ( Rdnbnk ( z)  Rnbnk ( z) Rnb1nk ( z)Ppbnk ( z))lnb1nk ( z);
             h1bnnk (z)  (P1bnnk ( z)  Pn*(bnk ) (z)Pndbnk (z)Pgbnk (z))hndbnk (z)  Pn*(bnk ) (z)Ppbnk ( z)lnb1nk (z);
             x1b  nk ( z )  h1bn nk ( z )  l1b  nk ( z ); lnb1 nk ( z )  Rn*( b  nk ) ( z ) x1b  nk ( z );
            h1b  nk ( z )  P1b  nk ( z ) x1b  nk ( z ); x2b  nk ( z )  h1b  nk ( z )  l2b  nk ( z );
            ..............................................................
            hmb nk2 ( z )  Pmb2nk ( z ) xmb nk2 ( z ); lmb nk         b  nk        b  nk
                                                                    3 ( z )  Rm  3 ( z ) xm  2 ( z );

             xmb nk
                   1
                       g (z)   g r (z)
                                          ( z )  hmb nk2 ( z )  lmb 1nk  g (z)   g r (z) ( z );
                 b  nk  g (z)  g p (z)               b  nk  g p (z)
             hm 1                            ( z )  Pm 1                  ( z ) xmb nk
                                                                                         1
                                                                                             g (z)
                                                                                                    ( z ); lmb nk2 ( z )  Rmb nk2 ( z ) xmb nk
                                                                                                                                                   1 ( z );
                 b  nk  g (z)   g p (z)             b  nk  g (z)  g p (z)
             xm                               ( z )  hm 1                         ( z )  lmb  nk ( z );
                b  nk                 b  nk         b  nk              b  nk  g (z)   g r (z)
             h  m        ( z)  P      m        (z) x m        ( z ); l   m 1                         ( z )  Rmb 1nk   gr (z) ( z ) xmb  nk  g (z) ( z );
             xbf  nk ( z)  hmb  nk ( z )  l bf  nk ( z );
             hbf  nk ( z )  Pfb  nk ( z ) xbf  nk ( z ); lmb  nk ( z )  Rmb  nk ( z ) xbf  nk ( z );
             xofb  nk ( z)  hbf  nk ( z )  lofb  nk ( z );
             hofb  nk ( z )  Pofb  nk ( z ) xofb  nk ( z );
             xсb  nk ( z )  hofb  nk ( z ); lofb  nk ( z )  Rofb  nk ( z ) xсb  nk ( z );
             hcb  nk ( z )  Pcb  nk ( z ) xcb  nk ( z ),                                                                                                        (1)
where xi ( z ), xn ( z ), xf ( z ), xof ( z ), xc ( z ) – z-image of the ink flow thickness at the
            


contact points of the ink printing system elements (i=1, 2, 3,…, m) within the ν-th
microflow (ν=1, 2, 3,…, nk); Pd j ( z ) , Rdj ( z ) – operators of ink transfer by fountain
roller (j - number of ink supply zone); Pn ( z ) , Rn ( z ) and P *n ( z ) , R *n ( z ) – opera-
tors of ink transfer by ductor roller during contact with a fountain roller and the first
distributing roller; Pnd ( z ) , P1n ( z ) і Rn1 ( z ) , Rdn ( z ) – operators of ink transfer by the
ductor roller from the fountain roller to the distributing roller and in the opposite di-
rection to the fountain roller; Pi ( z ) , Ri ( z ) – operators of transferring the direct and
reverse ink microflows by rollers in a circular direction; Pf ( z ) , Pof ( z ) , Rf ( z ) ,
Rof ( z ) – operators of transferring the direct and reverse microflows by surfaces of
the plate and offset cylinders; Pc ( z ) – operator of transferring the ink microflows
from an offset cylinder to paper; hdj ( z ) – z-image of the ink thickness on the surface
of the fountain roller at the exit of the gap between the fountain blade and the ductor
within j-th zone of its supply; hc ( z ) – z-images of ink thicknesses transmitted to
paper along the printing direction within the width of the ν-th microflow;
   b   g ( z )
 Pm 1 p ( z ) , Rmb 1  gr ( z ) ( z ) – operators of transfer the direct and reverse ink micro-
flows by an oscillator cylinder in the axial direction; b – the number of microflows in
a separate zone; g ( z ) - movement of the oscillator cylinder in the axial direction;
g r ( z ) , g p ( z ) - movement of the direct and reverse ink microflows by an oscillator
cylinder between its contact points with adjacent rollers.


3       Results of modeling

Based on the three-dimensional mathematical model (1) we build a simulator of the
ink printing system in the Matlab Simulink software package. Sets in the simulator
parameters of geometric sizes of the ink printing system elements through the corre-
sponding transport delays of the ink transfer between the rollers and cylinders contact
points; transmission coefficients of forward and reverse ink flows in a circular direc-
tion are 0,5; transmission coefficients on paper transfer – 0,7; the maximum axial
stroke value of the oscillator cylinder bos max is considered equal to the width of the
ink supply zone.
   For research, we develop a test form, which is shown in Fig. 2. Using the computer
program “InkUnit” [11] determines the density of the form's zonal filling with print-
ing elements. Using the technology proposed in [12], we determine the parameters of
the input zonal task for different axial stroke value of the oscillator cylinder (table 1).
   In determining the parameters of the input task, the average values of the form fill-
ing density with printing elements and the ink thickness in the respective zones of the
imprint were used. In the simulation, the average values of the ink thicknesses error
did not exceed 3%, which is significantly less than the allowable value of the predict-
ed standard ISO 12647-1, i.e. 5%. Given that the area of one zone is large enough and
can be tens of centimeters square, such accuracy is not a guarantee that individual
parts of the image within the same zone or adjacent zones will not exceed the permis-
sible limits.
                              1   2       3     4      5      6      7        8   9




                                          A            B             C
                                              Fig. 2. Test form.

             Table 1. Input task parameters for two modes of oscillator cylinder operation.

№ zone          1         2           3          4           5            6           7      8        9
         j
    k   z     0,0916    0,3215    0,3073      0,3144       0,2987    0,3006       0,2932   0,2261   0,0490
                                                       0,1 bos max
hdj , μm        9,1      30,8      30,0        28,8         27,9         28,4      27,9     22,0     6,9
                                                           bos max
  j
hd , μm        15,0      22,4      27,6        28,8         27,9         27,7      25,2     19,3     15,2

Such assumptions can only be verified if 3-D imprints are obtained. In Fig. 3 presents
a three-dimensional image of the imprints obtained as a result of modeling the ink
printing system at the maximum axial stroke value of the oscillator cylinder.
   Since one of the objects that generate significant technological perturbations to the
ink transfer process is the oscillator cylinder, so we will investigate its effect on the
accuracy of reproduction of imprints. To analyze the influence of the operation mode
the oscillator cylinder on the ink transfer on the imprints, we derive the longitudinal
profiles of the ink microflows at different axial stroke values of the oscillator cylinder
(Fig. 4). The cross sections of the imprint’s ink thickness obtained for positions A, B,
and C of the printing form shown in Fig. 2.
                      Fig. 3. Three-dimensional image of the imprint.

The profiles of the imprints intersections for the two variants of the axial stroke coin-
cide. However, as can be seen from Fig. 4a, the deviation of the ink thickness in the
middle zone of the imprint (position B) is in the range -8÷5% of the standard value
ISO 12647-1. At the left edge of the imprint (position A), the deviation is from -11%
to 13%. At the right edge of the imprint (position C) – from -13% to 12%. A similar
character of the change in the ink thickness in the corresponding positions of different
imprint zones is observed even with the maximum value of the axial stroke (Fig. 4b).
The research confirmed that the magnitude of the axial stroke greatly affects the redis-
tribution of ink flows at the output of the ink printing system both longitudinally and
across the imprint. Therefore, this factor must be taken into account when setting up
ink printing systems. As shown by the simulation results, the correction of the axial
stroke value influence obtained based on the average values of the ink flows thick-
nesses in the zones, i.e. based on two-dimensional models, does not provide the re-
quired accuracy of the imprints.
                         a)                                              b)
              Fig. 4. Ink sections in different areas of three-dimensional imprint:
          a) at the axial stroke value 0,1 bos max ; b) at the axial stroke value bos max .


To correct this problem, it is necessary to improve the accuracy of the ink printing
system adjustment, which can only be realized if the 3-D model is developed and
applied.


4      Conclusions

The functional scheme of the ink printing system was constructed, which reflects the
interaction of all components of the system. A mathematical model has been devel-
oped that takes into account the operation of each element ink printing system, de-
scribes in detail the process of discrete ink transfer from the fountain roller to the ink
distributing subsystem and the operation modes of the oscillator cylinder, which per-
forms axial displacement by sinusoidal law. The model reflects the process of ink
distribution and movement by surfaces of rollers and cylinders in three-dimensional
space. A simulator for the ink printing system was built. The influence of the axial
stroke value of the oscillator cylinders on the uniformity of the imprint's ink thickness
is simulated and researched.
    Based on the analysis of obtained results, it was established that determining the
parameters of the input task using a two-dimensional model of the ink printing system
does not provide an acceptable by the standard ISO 12647-1 of imprints accuracy. In
two-dimensional models, the influence of the oscillator cylinder operation mode was
taken into account due to the corresponding change in the transmission coefficients of
the forward and reverse ink flows in the axial direction. Therefore, in two-
dimensional models, individual ink transfer zones are only displayed by their profile.
Three-dimensional models make it possible to take into account not only the width of
the supply zones and ink transportation to imprints but also to reproduce three-
dimensional images of imprints that give complete information about the surface re-
lief of the imprint. Therefore, three-dimensional models should be used for a more
accurate set-up of ink printing systems.


References
 1. Kenneth, F. Hird: Offset Lithographic Technology. Goodheart-Willcox Company (2000).
 2. Kipphan, H.: Handbook of Print Media. Springer-Verlag, New York (2001).
 3. Mei Ni Guo: The Dynamic Property Analysis of Ink System in Offset Press. Advanced
    Materials Research, vols. 199-200, pp. 132-136. Trans Tech Publications, Switzer-
    land (2011).
 4. Qiu Min Wu, Ji Mei Wu, Rui Wang: Study for Dynamic Property of the Inking System of
    Offset Press Based on Matlab. Applied Mechanics and Materials, vols. 121-126, pp. 392-
    396. Trans Tech Publications, Switzerland (2012).
 5. Jieyue Yu, Pengxiang Wei: Simulation the axial oil distribution of offset printing. 2011 In-
    ternational Conference on Electrical and Control Engineering, pp.: 4968-4971. Yichang,
    China (2011).
 6. ZHAO Ji-bin, TONG Cheng-nan: Research on Properties of Intermittent Transferring Ink-
    ing system. Journal of Beijing Institute of Graphic Communication vol.16. China (2008).
    Homepage, http://en.cnki.com.cn, last accessed 2019/10/12.
 7. Jieyue Yu, Liu Zhen: Study on the ink flow model of Lithographic Printing. 2011 4th In-
    ternational Congress on Image and Signal Processing, vol. 4, pp. 1757-1761. Shanghai,
    China (2011).
 8. Shtolyakov, V., Rumyantsev, V.: Printing equipment. Moscow State University of Print-
    ing, Moscow (2011).
 9. Verkhola, M., Guk, I., Spolyak, R.: Information technology for determining the effect of
    the ink transfer between elements of the ink printing systems on the thickness of its layer
    on the imprints. Computer technologies of printing 28, 31-40 (2012).
10. Verkhola, M., Guk, I., Panovyk, U., Spolyak, R.: Information technology of verification of
    models authenticity of ink printing systems with the drum cylinders. Technological com-
    plexes 1/1(11), 53-63 (2015).
11. Verkhola, M., Spoljak, R.: The computer program for automatically determining the zonal
    filling coefficients of printing forms “InkUnit”. Ukraine, assignee. Patent 58823.
    26.02.2015. Print.
12. Verkhola, M., Spoljak, R.: Automatic detection of input task of a consistent ink printing
    system for different loads. Computer technologies of printing 25, 20-30 (2011).