Abstract:
An ink transport route switching apparatus in an inking device of a printing press, the inking device being arranged to supply ink to a printing plate via an ink transport route composed of a plurality of ink rollers, and equipped with an ink distribution roller which moves to a first position and a second position to switch the ink transport route between a first ink transport route and a second ink transport route, the ink transport route switching apparatus comprising a control device which finds image area rates or image areas in a plurality of ranges, divided in a lateral direction, of an image to be printed; finds a difference between the image area rates or the image areas in the adjacent ranges; compares the difference between the image area rates or the image areas with a reference value for switching the ink transport route.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to an ink transport route switching method and apparatus in an inking device of an offset printing press, an intaglio printing press, a gravure printing press, etc.  
         [0003]     2. Description of the Related Art  
         [0004]     Generally, an inking device of an offset printing press transports and transfers ink, which is stored in an ink fountain, in a roller arrangement by the following route: ink fountain roller→ink ductor roller→ink distribution roller→ink oscillating roller→ink form roller. In this manner, the inking device supplies ink to a printing plate wound round the circumferential surface of a plate cylinder, and a print (image) is produced on paper in a printing unit.  
         [0005]     With the above-mentioned inking device, printing is performed via the ink transport route in which ink is always supplied, at a predetermined rate, to a plurality of ink form rollers for transfer of the ink, regardless of the image.  
         [0006]     As shown in  FIGS. 5   a ,  5   b , therefore, the following printing troubles may be caused: If the image area (a hatched region in the drawings) is uniform in the sheet width direction, and the amount of dampening water supplied to the printing plate is too large (see  FIG. 5   a ), color irregularities occur. If the image area is nonuniform in the sheet width direction (see  FIG. 5   b ), a ghost appears in which the color density at a portion e, in particular, increases.  
         [0007]     In earlier technologies, as disclosed in Japanese Unexamined Patent Publication No. 1997-272196, an operator confirms the image to be printed. If the image is such that the image area rate is greatly different in the sheet width direction and has a high possibility for ghost occurrence, the operator manually throws a switching roller onto a predetermined ink oscillating roller to supply a larger amount of ink to the ink form roller on the dampening side, thereby establishing an ink roller arrangement in which a ghost minimally appears. If the image is such that the image area rate is uniform in the sheet width direction and has a high possibility for color irregularities, the operator manually throws the switching roller off the predetermined ink oscillating roller to supply a smaller amount of ink to the ink form roller on the dampening side, thereby establishing an ink roller arrangement in which color irregularities minimally occur.  
         [0008]     With the inking device disclosed in Japanese Unexamined Patent Publication No. 1997-272196, however, the operator makes a judgment and carries out switching manually. This has posed a first problem that the operator is burdened, the rate of operation is decreased, and the operator sometimes forgets to do switching, thus performing switching after start of printing. This has led to a further decrease in the rate of operation, and a waste of printing material.  
         [0009]     If the image area rate is low overall, the following second problem is posed: In response to such a low image area rate, an attempt may be made to throw the switching roller onto the above-mentioned ink oscillating roller, thereby supplying a larger amount of ink to the ink form roller on the dampening side. In this case, an excess of dampening water rises into the inking device, emulsifying the ink. This makes the operator&#39;s judgment difficult, increasing burden on the operator and decreasing the rate of operation. Further, a mistake in switching is induced, whereby switching is performed after printing is started. This has led to an even greater decrease in the rate of operation, and a further waste of printing material.  
         [0010]     The present invention has been accomplished in light of the above-described problems with the earlier technologies. The present invention provides an ink transport route switching method and apparatus in the inking device of a printing press, which, before start of printing, automatically perform switching to an ink transport route for supplying ink, at an optimum ink supply rate, to each ink form roller according to printing image conditions, thereby enabling a high quality printing product to be always produced, shortening the printing make-ready time and cutting down on the amount of printed wasted paper.  
       SUMMARY OF THE INVENTION  
       [0011]     A first aspect of the present invention is an ink transport route switching method in an inking device of a printing press, the inking device being arranged to supply ink stored in an ink fountain to a printing plate via an ink transport route composed of a plurality of ink rollers, and the inking device being equipped with a switching roller which moves to a first position and a second position to switch the ink transport route between a first ink transport route and a second ink transport route,  
         [0012]     the ink transport route switching method comprising:  
         [0013]     finding image area rates or image areas in a plurality of ranges, divided in a lateral direction, of an image to be printed;  
         [0014]     finding a difference between the image area rates or the image areas in the adjacent ranges;  
         [0015]     comparing the difference between the image area rates or the image areas with a first reference value for switching the ink transport route; and  
         [0016]     moving the switching roller to the first position or the second position based on results of the comparison.  
         [0017]     A second aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the first aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the difference between the image area rates or the image areas is equal to or greater than, or is greater than, the first reference value, the switching roller is moved to the first position.  
         [0018]     A third aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the first aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the difference between the image area rates or the image areas is equal to or greater than, or is greater than, the first reference value, the switching roller is moved to the first position.  
         [0019]     A fourth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the first aspect, further comprising: finding an average of the image area rates, or an average or a sum of the image areas, of a whole of the image to be printed; comparing the average of the image area rates, or the average or the sum of the image areas, with a second reference value for switching the ink transport route; and moving the switching roller to the first position or the second position based on results of the comparison.  
         [0020]     A fifth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the fourth aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the average of the image area rates, or the average or the sum of the image areas is equal to or greater than, or is greater than, the second reference value, the switching roller is moved to the first position.  
         [0021]     A sixth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the fourth aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the average of the image area rates, or the average or the sum of the image areas is equal to or greater than, or is greater than, the second reference value, the switching roller is moved to the first position.  
         [0022]     A seventh aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the first aspect, wherein the plurality of the ranges divided in the lateral direction are ranges corresponding to ink fountain keys.  
         [0023]     An eighth aspect of the invention is an ink transport route switching method in an inking device of a printing press, the inking device being arranged to supply ink stored in an ink fountain to an ink fountain roller through clearances between ink fountain keys and the ink fountain roller, and supply the ink supplied to the ink fountain roller to a printing plate via an ink transport route composed of a plurality of ink rollers, and the inking device being equipped with a switching roller which moves to a first position and a second position to switch the ink transport route between a first ink transport route and a second ink transport route,  
         [0024]     the ink transport route switching method comprising:  
         [0025]     finding a difference between opening amounts of the adjacent ink fountain keys;  
         [0026]     comparing the difference between the opening amounts of the ink fountain keys with a third reference value for switching the ink transport route; and  
         [0027]     moving the switching roller to the first position or the second position based on results of the comparison.  
         [0028]     A ninth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the eighth aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the difference between the opening amounts of the ink fountain keys is equal to or greater than, or is greater than, the third reference value, the switching roller is moved to the first position.  
         [0029]     A tenth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the eighth aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the difference between the opening amounts of the ink fountain keys is equal to or greater than, or is greater than, the third reference value, the switching roller is moved to the first position.  
         [0030]     An eleventh aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the eighth aspect, further comprising: finding an average or a sum of the opening amounts of all the ink fountain keys for each color; comparing the average or the sum of the opening amounts of all the ink fountain keys for each color with a fourth reference value for switching the ink transport route; and moving the switching roller to the first position or the second position based on results of the comparison.  
         [0031]     A twelfth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the eleventh aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the average or the sum of the opening amounts of all the ink fountain keys for each color is equal to or greater than, or is greater than, the fourth reference value, the switching roller is moved to the first position.  
         [0032]     A thirteenth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the eleventh aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the average or the sum of the opening amounts of all the ink fountain keys for each color is equal to or greater than, or is greater than, the fourth reference value, the switching roller is moved to the first position.  
         [0033]     A fourteenth aspect of the invention is the ink transport route switching method in an inking device of a printing press according to the first or eight aspect, further comprising performing processings for each color.  
         [0034]     A fifteenth aspect of the invention is an ink transport route switching apparatus in an inking device of a printing press, the inking device being arranged to supply ink stored in an ink fountain to a printing plate via an ink transport route composed of a plurality of ink rollers, and the inking device being equipped with a switching roller which moves to a first position and a second position to switch the ink transport route between a first ink transport route and a second ink transport route,  
         [0035]     the ink transport route switching apparatus comprising:  
         [0036]     a control device which  
         [0037]     finds image area rates or image areas in a plurality of ranges, divided in a lateral direction, of an image to be printed,  
         [0038]     finds a difference between the image area rates or the image areas in the adjacent ranges,  
         [0039]     compares the difference between the image area rates or the image areas with a first reference value for switching the ink transport route, and  
         [0040]     moves the switching roller to the first position or the second position based on results of the comparison.  
         [0041]     A sixteenth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the fifteenth aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the difference between the image area rates or the image areas is equal to or greater than, or is greater than, the first reference value, the control device moves the switching roller to the first position.  
         [0042]     A seventeenth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the fifteenth aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the difference between the image area rates or the image areas is equal to or greater than, or is greater than, the first reference value, the control device moves the switching roller to the first position.  
         [0043]     An eighteenth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the fifteenth aspect, wherein the control device finds an average of the image area rates, or an average or a sum of the image areas, of a whole of the image to be printed; compares the average of the image area rates, or the average or the sum of the image areas, with a second reference value for switching the ink transport route; and moves the switching roller to the first position or the second position based on results of the comparison.  
         [0044]     A nineteenth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the eighteenth aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the average of the image area rates, or the average or the sum of the image areas is equal to or greater than, or is greater than, the second reference value, the control device moves the switching roller to the first position.  
         [0045]     A twentieth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the eighteenth aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the average of the image area rates, or the average or the sum of the image areas is equal to or greater than, or is greater than, the second reference value, the control device moves the switching roller to the first position.  
         [0046]     A twenty-first aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the fifteenth aspect, wherein the plurality of the ranges divided in the lateral direction are ranges corresponding to ink fountain keys.  
         [0047]     A twenty-second aspect of the invention is an ink transport route switching apparatus in an inking device of a printing press, the inking device being arranged to supply ink stored in an ink fountain to an ink fountain roller through clearances between ink fountain keys and the ink fountain roller, and supply the ink supplied to the ink fountain roller to a printing plate via an ink transport route composed of a plurality of ink rollers, and the inking device being equipped with a switching roller which moves to a first position and a second position to switch the ink transport route between a first ink transport route and a second ink transport route,  
         [0048]     the ink transport route switching apparatus comprising:  
         [0049]     a control device which  
         [0050]     finds a difference between opening amounts of the adjacent ink fountain keys,  
         [0051]     compares the difference between the opening amounts of the ink fountain keys with a third reference value for switching the ink transport route, and  
         [0052]     moves the switching roller to the first position or the second position based on results of the comparison.  
         [0053]     A twenty-third aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the twenty-second aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the difference between the opening amounts of the ink fountain keys is equal to or greater than, or is greater than, the third reference value, the control device moves the switching roller to the first position.  
         [0054]     A twenty-fourth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the twenty-second aspect, the inkling device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the difference between the opening amounts of the ink fountain keys is equal to or greater than, or is greater than, the third reference value, the control device moves the switching roller to the first position.  
         [0055]     A twenty-fifth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the twenty-second aspect, wherein the control device finds an average or a sum of the opening amounts of all the ink fountain keys for each color; compares the average or the sum of the opening amounts of all the ink fountain keys for each color with a fourth reference value for switching the ink transport route; and moves the switching roller to the first position or the second position based on results of the comparison.  
         [0056]     A twenty-sixth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the twenty-fifth aspect, wherein the first ink transport route is the ink transport route in which a ghost occurs with lower possibility than the second ink transport route, and when the average or the sum of the opening amounts of all the ink fountain keys for each color is equal to or greater than, or is greater than, the fourth reference value, the control device moves the switching roller to the first position.  
         [0057]     A twenty-seventh aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the twenty-fifth aspect, the inking device further comprising a plurality of ink form rollers for supplying the ink to the printing plate, and a dampener for supplying dampening water to the printing plate, wherein the first ink transport route is the ink transport route for supplying a larger amount of the ink to the ink form rollers on a side of the dampener than the second ink transport route, and when the average or the sum of the opening amounts of all the ink fountain keys for each color is equal to or greater than, or is greater than, the fourth reference value, the control device moves the switching roller to the first position.  
         [0058]     A twenty-eighth aspect of the invention is the ink transport route switching apparatus in an inking device of a printing press according to the fifteenth or twenty-second aspect, arranged to perform processings for each color.  
         [0059]     According to the present invention, switching to the ink transport route for supplying ink, at an optimum ink supply rate, to each ink form roller according to printing image conditions can be automatically performed before start of printing, whereby a high quality printing product can be always produced, the printing make-ready time can be shortened, and the amount of printed wasted paper can be decreased. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0060]     The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:  
         [0061]      FIG. 1  is an explanation drawing showing the roller arrangement of an inking device illustrating Embodiment 1 of the present invention;  
         [0062]      FIG. 2  is a developed sectional plan view of an ink transport route switching apparatus;  
         [0063]      FIG. 3  is a side view of the ink transport route switching apparatus;  
         [0064]      FIG. 4  is an explanation drawing of an image area rate difference Dt between adjacent ink fountain keys, and an image area rate average value Dav of the adjacent ink fountain keys;  
         [0065]      FIGS. 5   a  and  5   b  are explanation drawings of printing products having different images;  
         [0066]      FIG. 6   a  is a block diagram of an ink supply amount control device;  
         [0067]      FIG. 6   b  is a block diagram of the ink supply amount control device;  
         [0068]      FIG. 7  is a block diagram of an ink fountain key opening amount control device;  
         [0069]      FIG. 8  is a block diagram of an ink fountain roller rotation amount control device;  
         [0070]      FIG. 9   a  is an action flow chart of the ink supply amount control device;  
         [0071]      FIG. 9   b  is an action flow chart of the ink supply amount control device;  
         [0072]      FIG. 9   c  is an action flow chart of the ink supply amount control device;  
         [0073]      FIG. 10   a  is an action flow chart of the ink supply amount control device;  
         [0074]      FIG. 10   b  is an action flow chart of the ink supply amount control device;  
         [0075]      FIG. 11   a  is an action flow chart of the ink supply amount control device;  
         [0076]      FIG. 11   b  is an action flow chart of the ink supply amount control device;  
         [0077]      FIG. 12   a  is an action flow chart of the ink fountain key opening amount control device;  
         [0078]      FIG. 12   b  is an action flow chart of the ink fountain key opening amount control device;  
         [0079]      FIG. 13  is an action flow chart of the ink fountain roller rotation amount control device;  
         [0080]      FIG. 14   a  is a block diagram of an ink supply amount control device showing Embodiment 2 of the present invention;  
         [0081]      FIG. 14   b  is a block diagram of the ink supply amount control device;  
         [0082]      FIG. 15  is a block diagram of an ink fountain key opening amount control device in Embodiment 2;  
         [0083]      FIG. 16  is a block diagram of an ink fountain roller rotation amount control device in Embodiment 2;  
         [0084]      FIG. 17   a  is an action flow chart of the ink supply amount control device;  
         [0085]      FIG. 17   b  is an action flow chart of the ink supply amount control device;  
         [0086]      FIG. 17   c  is an action flow chart of the ink supply amount control device;  
         [0087]      FIG. 18   a  is an action flow chart of the ink supply amount control device;  
         [0088]      FIG. 18   b  is an action flow chart of the ink supply amount control device;  
         [0089]      FIG. 18   c  is an action flow chart of the ink supply amount control device;  
         [0090]      FIG. 19   a  is an action flow chart of the ink supply amount control device;  
         [0091]      FIG. 19   b  is an action flow chart of the ink supply amount control device;  
         [0092]      FIG. 20   a  is an action flow chart of the ink fountain key opening amount control device;  
         [0093]      FIG. 20   b  is an action flow chart of the ink fountain key opening amount control device;  
         [0094]      FIG. 21  is an action flow chart of the ink fountain roller rotation amount control device;  
         [0095]      FIG. 22   a  is a block diagram of an ink supply amount control device showing Embodiment 3 of the present invention;  
         [0096]      FIG. 22   b  is a block diagram of the ink supply amount control device;  
         [0097]      FIG. 23  is a block diagram of an ink fountain key opening amount control device in Embodiment 3;  
         [0098]      FIG. 24  is a block diagram of an ink fountain roller rotation amount control device in Embodiment 3;  
         [0099]      FIG. 25   a  is an action flow chart of the ink supply amount control device;  
         [0100]      FIG. 25   b  is an action flow chart of the ink supply amount control device;  
         [0101]      FIG. 25   c  is an action flow chart of the ink supply amount control device;  
         [0102]      FIG. 25   d  is an action flow chart of the ink supply amount control device;  
         [0103]      FIG. 25   e  is an action flow chart of the ink supply amount control device;  
         [0104]      FIG. 26   a  is an action flow chart of the ink supply amount control device;  
         [0105]      FIG. 26   b  is an action flow chart of the ink supply amount control device;  
         [0106]      FIG. 26   c  is an action flow chart of the ink supply amount control device;  
         [0107]      FIG. 27   a  is an action flow chart of the ink fountain key opening amount control device;  
         [0108]      FIG. 27   b  is an action flow chart of the ink fountain key opening amount control device;  
         [0109]      FIG. 28  is an action flow chart of the ink fountain roller rotation amount control device;  
         [0110]      FIG. 29   a  is a block diagram of a switching control device showing Embodiment 4 of the present invention;  
         [0111]      FIG. 29   b  is a block diagram of the switching control device;  
         [0112]      FIG. 30  is a block diagram of an ink fountain key opening amount control device in Embodiment 4;  
         [0113]      FIG. 31   a  is an action flow chart of the switching control device;  
         [0114]      FIG. 31   b  is an action flow chart of the switching control device;  
         [0115]      FIG. 31   c  is an action flow chart of the switching control device;  
         [0116]      FIG. 31   d  is an action flow chart of the switching control device;  
         [0117]      FIG. 31   e  is an action flow chart of the switching control device;  
         [0118]      FIG. 32  is an action flow chart of the switching control device; and  
         [0119]      FIG. 33  is an action flow chart of the ink fountain key opening amount control device. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0120]     The ink transport route switching method and apparatus in an inking device of a printing press according to the present invention will be described in detail by embodiments of the invention with reference to the accompanying drawings.  
       Embodiment 1  
       [0121]      FIG. 1  is an explanation drawing showing the roller arrangement of an inking device illustrating Embodiment 1 of the present invention.  FIG. 2  is a developed sectional plan view of an ink transport route switching apparatus.  FIG. 3  is a side view of the ink transport route switching apparatus.  FIG. 4  is an explanation drawing of an image area rate difference Dt between adjacent ink fountain keys, and an image area rate average value Dav of the adjacent ink fountain keys.  FIGS. 5   a  and  5   b  are explanation drawings of printing products having different images.  FIG. 6   a  is a block diagram of an ink supply amount control device.  FIG. 6   b  is a block diagram of the ink supply amount control device.  FIG. 7  is a block diagram of an ink fountain key opening amount control device.  FIG. 8  is a block diagram of an ink fountain roller rotation amount control device.  FIG. 9   a  is an action flow chart of the ink supply amount control device.  FIG. 9   b  is an action flow chart of the ink supply amount control device.  FIG. 9   c  is an action flow chart of the ink supply amount control device.  FIG. 10   a  is an action flow chart of the ink supply amount control device.  FIG. 10   b  is an action flow chart of the ink supply amount control device.  FIG. 11   a  is an action flow chart of the ink supply amount control device.  FIG. 11   b  is an action flow chart of the ink supply amount control device.  FIG. 12   a  is an action flow chart of the ink fountain key opening amount control device.  FIG. 12   b  is an action flow chart of the ink fountain key opening amount control device.  FIG. 13  is an action flow chart of the ink fountain roller rotation amount control device.  
         [0122]     As shown in  FIG. 1 , a roller arrangement for supplying ink stored in an ink fountain  1  to the plate surface (printing plate) of a plate cylinder  7  is composed of an ink fountain roller  2 , an ink ductor roller  3 , ink distribution rollers  4   a  to  4   g , ink oscillating rollers  5   a  to  5   c , and ink form rollers  6   a  to  6   c . In the drawing, the numeral  8  denotes a dampener composed of a water fountain roller  8   a , a ductor roller  8   b , a reciprocating roller  8   c , and a dampening form roller  8   d , and adapted to supply dampening water to the surface of a non-image area in the plate surface of the plate cylinder  7 .  
         [0123]     In the present embodiment, the ink distribution roller  4   e  in constant contact with the ink distribution roller  4   d  disposed ahead of the ink oscillating roller  5   a  can be thrown on and off the ink oscillating roller  5   b  disposed directly behind the ink distribution roller  4   e , and thus functions as a so-called switching roller.  
         [0124]     When the ink distribution roller  4   e  contacts the ink oscillating roller  5   b  at a predetermined pressure (the position of contact: first position), the length of the ink transport route to the ink form rollers  6   b ,  6   c , especially the ink form roller  6   c , on the side of the dampener  8  becomes small, so that a larger amount of ink is supplied to the ink form rollers  6   b ,  6   c , especially the ink form roller  6   c  (namely, the ink transport route for supply of a larger amount of ink to the ink form rollers  6   b ,  6   c  on the side of the dampener  8 : first ink transport route). When the ink distribution roller  4   e  separates from the ink oscillating roller  5   b  (the position of non-contact: second position), on the other hand, the length of the ink transport route to the ink form rollers  6   b ,  6   c , especially the ink form roller  6   c , on the side of the dampener  8  becomes large, so that a smaller amount of ink is supplied to the ink form rollers  6   b ,  6   c , especially the ink form roller  6   c  (namely, the ink transport route for supply of a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the side of the dampener  8 : second ink transport route).  
         [0125]     A switching means for the ink distribution roller  4   e  has opposite end shaft portions of the ink oscillating roller  5   a  journaled pivotably and axially slidably on right and left frames  10  (only the left frame is shown) of the printing press via bearing housings  11 , as shown in  FIGS. 2 and 3 .  
         [0126]     A first lever  12 , formed in a Y-shape, has a base end portion journaled to each of the opposite end shaft portions of the ink oscillating roller  5   a . Opposite end shaft portions of the ink distribution roller  4   d  are pivotably journaled at leading end portions of one side (right-hand side in  FIG. 3 ) of the first levers  12  via flanges  13   a ,  13   b  and bearing caps  14  pivotally supported by the flanges  13   a ,  13   b.    
         [0127]     An intermediate portion (in the right-and-left direction in  FIG. 3 ) of a second lever  15  pivotably supported on the outer periphery of the flange  13   b . Each of the opposite end shaft portions of the ink distribution roller  4   e , as the switching roller, is pivotably supported at one end portion (right-hand portion in  FIG. 3 ) of the second lever  15  via a bearing cap  16 .  
         [0128]     An eccentric bush  17  is unreleasably fitted to a leading end portion on the other side (left-hand side) of the first lever  12 . A base end portion of a switching lever  18  is journaled on an outer end portion of the outer periphery of the eccentric bush  17 . A stud pin  20  with a nut  19  is pivotably and unreleasably fitted into an inner peripheral axial hole of the eccentric bush  17  from the inner end side of the eccentric bush  17 .  
         [0129]     The nut  19  is attached perpendicularly to the axis of the stud pin  20 . A leading end of an adjusting screw  21  with a knob  22 , which is screwed to the nut  19 , penetrates the stud pin  20 , also penetrates a stud pin  23  unreleasably fitted to and passed through the other end portion (left-hand side in  FIG. 3 ) of the second lever  15 , and is then mounted to be unreleasable. A helical compression spring  24  is wound round the adjusting screw  21  between the stud pins  20  and  23 .  
         [0130]     Thus, by gripping the knob  22  and turning the adjusting screw  21 , the distance between the stud pins  20  and  23  is changed according to the axial movement of the adjusting screw  21 , whereby the second lever  15  swings about the flange  13   a ,  13   b  to adjust the nip pressure of the ink distribution roller  4   e  on the ink oscillating roller  5   b.    
         [0131]     A piston rod tip of an air cylinder  25 - 1  is bound to a leading end portion of the switching lever  18  by a pin  25 . A head portion of the air cylinder  25 - 1  is downwardly bound, by a pin  26   a , to a support lever  26  secured to the first lever  12 .  
         [0132]     In the state of the switching lever  18  (as indicated by solid lines in  FIG. 3 ) in which the air cylinder  25 - 1  is contracted, the ink distribution roller  4   e  is contacted by the ink oscillating roller  5   b . In the state of the switching lever  18  (as indicated by dashed lines in  FIG. 3 ) in which the air cylinder  25 - 1  is expanded, on the other hand, the downward displacement of the adjusting screw  21  according to the eccentric rotation of the eccentric bush  17  pivots the second lever  15  counterclockwise in  FIG. 3  about the flanges  13   a ,  13   b  to separate the ink distribution roller  4   e  from the ink oscillating roller  5   b . The above-described switching means for the ink distribution roller  4   e  is similarly configured on the right frame side which is not illustrated.  
         [0133]     As shown in  FIGS. 6   a  and  6   b , the air cylinder  25 - 1  is driven and controlled by an ink supply amount control device  30  to be capable of automatically performing, before start of printing, switching to the ink transport route (the first ink transport route or the second ink transport route) for supplying ink, at an optimum ink supply rate, to the ink form rollers  6   a ,  6   b ,  6   c  in accordance with printing image conditions as shown in  FIGS. 5   a ,  5   b.    
         [0134]     The ink supply amount control device  30  comprises CPU  31 , RAM  32 , ROM  33 , an input/output device  53 , an input/output device  54 , an interface  55 , and the following memories connected by a bus-line (BUS)  56 , as shown in  FIGS. 6   a  and  6   b : A memory  34  for storing the total value IRs of the image area rates of the respective printing units used in the coming printing; a memory  35  for storing the average value IRam of the image area rates of the respective printing units used in the coming printing; a memory  36  for storing a second reference value R 2   m  for switching corresponding to each ink color ICm; a memory  37  for storing the No. of a printing unit for switching roller throw-on; a memory  38  for storing an image area rate-ink fountain key opening amount conversion table corresponding to each ink color ICm; a memory  39  for storing the ink fountain key opening amount Kmn 2  of each printing unit used in the coming printing; a memory  40  for storing a printing unit No. for setting switching roller throw-on; a memory  41  for storing a reference ink fountain roller rotation amount Rm corresponding to each ink color ICm; a memory  42  for storing the number Mmax of the printing units used in the coming printing; a memory  43  for storing the No. UNm of a printing unit used in the coming printing; a memory  44  for storing the ink color ICm of each printing unit UNm used in the coming printing; a memory  45  for storing an image area rate IRmn in a range corresponding to each ink fountain key of each printing unit UNm used in the coming printing; a memory  46  for storing a count value M; a memory  47  for storing a count value N 1 ; a memory  48  for storing the difference (IRm(n 1 - 1 )−IRmn 1 ) between an image area rate IRm(n 1 - 1 ) in a range corresponding to the (N 1 - 1 )th ink fountain key and an image area rate IRmn 1  in a range corresponding to the N 1 th ink fountain key of each printing unit UNm used in the coming printing; a memory  49  for storing the absolute value |IRm(n 1 - 1 )−IRmn 1 | of the difference between the image area rate IRm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key and the image area rate IRmn 1  in the range corresponding to the N 1 th ink fountain key of each printing unit UNm used in the coming printing; a memory  50  for storing a first reference value R 1   m  for switching corresponding to each ink color ICm; a memory  51  for storing the total number Nmax of the ink fountain keys of each printing unit; and a memory  52  for storing a count value N 2 .  
         [0135]     An input device  57 , such as a keyboard, various switches, and a button, a display device  58 , such as CRT and a lamp, and an output device  59 , such as an F-D drive, and a printer, are connected to the input/output device  53 . To the input/output device  54 , there are connected a valve  60 - 1  for an air cylinder for switching the roller route of the first printing unit through a valve  60 -M for an air cylinder for switching the roller route of the Mth printing unit corresponding to the air cylinder  25 - 1  for switching the roller route of the first printing unit through the air cylinder  25 -M for switching the roller route of the Mth printing unit.  
         [0136]     To the interface  55 , there are connected a printing press control device  61 , a first (first printing unit) ink fountain roller rotation amount control device  63 - 1  through an Mth (Mth printing unit) ink fountain roller rotation amount control device  63 -M, and a first ink fountain key opening amount control device  62 - 1  through an (M×N)th ink fountain key opening amount control device  62 -(M×N).  
         [0137]     The printing press control device  61  controls the entire printing press, including a feeding unit, first to Mth printing units, and a delivery unit which are not shown.  
         [0138]     As shown in  FIG. 7 , the first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) comprise CPU  64 , RAM  65 , ROM  66 , and a memory  67  for storing a received ink fountain key opening amount Kmn, a memory  68  for storing a target ink fountain key opening amount, a memory  69  for storing the count value of a counter, and a memory  70  for storing a current ink fountain key opening amount, which are connected via a bus-line (BUS)  73  together with an input/output device  71  and an interface  72 .  
         [0139]     To the input/output device  71 , an ink fountain key drive motor  74  is connected via an ink fountain key drive motor driver  75 , and an ink fountain key drive motor rotary encoder  76  incorporated in the ink fountain key drive motor  74  is connected via a counter  77 . A detection signal from the ink fountain key drive motor rotary encoder  76  is inputted into the ink fountain key drive motor driver  75 . The aforementioned ink supply amount control device  30  is connected to the interface  72 .  
         [0140]     As shown in  FIG. 8 , the first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M comprise CPU  78 , RAM  79 , ROM  80 , and a memory  81  for storing a received ink fountain roller rotation amount Rm, and a memory  82  for storing a target ink fountain roller rotation amount, which are connected via a bus-line (BUS)  85  together with an input/output device  83  and an interface  84 .  
         [0141]     To the input/output device  83 , an ink fountain roller drive motor  86  is connected via an ink fountain roller drive motor driver  87 , and an ink fountain roller drive motor rotary encoder  88  incorporated in the ink fountain roller drive motor  86  is connected via an F/V converter  89  and an A/D converter  90 . A detection signal from the ink fountain roller drive motor rotary encoder  88  is inputted into the ink fountain roller drive motor driver  87 . The aforementioned ink supply amount control device  30  is connected to the interface  84 .  
         [0142]     Because of the above configuration, the ink supply amount control device  30  acts in accordance with action flows shown in  FIGS. 9   a  through  9   c ,  FIGS. 10   a  and  10   b , and  FIGS. 11   a  and  11   b.    
         [0143]     That is, it is determined in Step P 1  whether an ink preset switch in the input/output device  57  is ON or not. If ON, each memory is initialized in Step P 2 . If not ON, it is determined in Step P 3  whether a printing completion signal has been outputted from the printing press control device  61 . If YES, outputting of a switching signal to the valves  60 - 1  through  60 -M for air cylinders for switching the roller routes of all printing units is stopped in Step P 4 , and the program returns to Step P 1 . If NO, the program immediately returns to Step P 1 .  
         [0144]     Then, in Step P 5 , the number Mmax of the printing units used in the coming printing, the printing unit No. UNm, the ink color ICm of each printing unit UNm, and the image area rate IRmn in a range corresponding to each ink fountain key are inputted, and stored into the memories  42  to  45 . In Step P 6 , 1 is written into the memory  46  for storing the count value M. In Step P 7 , 2 is written into the memory  47  for storing the count value N 1 .  
         [0145]     Then, in Step P 8 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 9 , the image area rate IRm(n 1 - 1 ) in a range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 . Also, in Step P 10 , the image area rate IRmn 1  in a range corresponding to the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 .  
         [0146]     Then, in Step P 11 , the difference (IRm(n 1 - 1 )−IRmn 1 ) between the image area rate IRm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area rate IRmn 1  in the range corresponding to the N 1 th ink fountain key is computed, and stored into the memory  48 . In Step P 12 , the absolute value |IRm(n 1 - 1 )−IRmn 1 | of the difference between the image area rate IRm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area rate IRmn 1  in the range corresponding to the N 1 th ink fountain key is computed, and stored into the memory  49 .  
         [0147]     Then, in Step P 13 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Also, in Step P 14 , the first reference value R 1   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  50 . Then, in Step P 15 , it is determined whether the absolute value |IRm(n 1 - 1 )−IRmn 1 | of the difference between the image area rate IRm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area rate IRmn 1  in the range corresponding to the N 1 th ink fountain key is equal to or larger than the first reference value R 1   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0148]     If YES in Step P 15 , the program shifts to Step P 22  to be described later. IF NO in Step P 15 , 1 is added, in step P 16 , to the count value N 1 , and the sum is written over the memory  47 .  
         [0149]     Then, in Step  17 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step  18 , it is determined whether the count value N 1  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M in Step P 19 , and the sum is written over the memory  46 . If NO, the program returns to Step P 9 .  
         [0150]     Then, in Step P 20 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 21 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the program shifts to Step P 36  to be described later. If NO, the program returns to Step P 7 .  
         [0151]     Then, in Step P 22 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 23 , the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing is initialized. Then, in Step P 24 , the image area rate IRmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 .  
         [0152]     Then, in Step P 25 , the value of the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing is loaded. Then, in Step P 26 , the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is added to the value of the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing, and the sum is written over the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing.  
         [0153]     Then, in Step P 27 , 1 is added to the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 28 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 29 , it is determined whether the count value N 2  is equal to or larger than the total number Nmax of the ink fountain keys of each printing unit.  
         [0154]     Then, in Step P 30 , the value of the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing is loaded. Then, in Step  31 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 32 , the value of the memory  34  for storing the total value IRs of the image area rates of the printing unit UNm used in the coming printing is divided by the total number Nmax of the ink fountain keys of each printing unit to obtain the average value IRam of the image area rate of the Mth printing unit UNm used in the coming printing, and this average value IRam is stored in the memory  35 .  
         [0155]     Then, in Step P 33 , the second reference value R 2   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  36 . Then, in Step P 34 , it is determined whether the average value IRam of the image area rate of the Mth printing unit UNm used in the coming printing is equal to or greater than the second reference value R 2   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0156]     If YES in Step P 34 , the No. UNm of the Mth printing unit used in the coming printing is written into the memory for storing the printing unit No. for switching roller throw-on in Step P 35 . Then, the program returns to Step P 19 . If NO in Step P 34 , the program returns to Step P 16 .  
         [0157]     If YES in Step  21 , 1 is written into the memory  46  for storing the count value M in Step P 36 , and 1 is written into the memory  52  for storing the count value N 2  in Step P 37 . Then, in Step P 38 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 .  
         [0158]     Then, in Step P 39 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 40 , the image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  38 . Then, in Step P 41 , the image area rate IRmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 .  
         [0159]     Then, in Step P 42 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is found from the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing by use of the image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the printing unit UNm used in the coming printing.  
         [0160]     Then, in Step P 43 , 1 is added to the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 44 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 , and in Step P 45 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color.  
         [0161]     If YES in Step P 45 , 1 is added to the count value M, and the sum is written over the memory  46  in Step P 46 . If NO in Step P 45 , the program returns to Step P 39 .  
         [0162]     Then, in Step P 47 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 48 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the contents of the memory  37  for storing the printing unit No. for switching roller throw-on are written, in Step P 49 , into the memory  40  for storing the printing unit No. for setting switching roller throw-on. If NO, the program returns to Step P 37 .  
         [0163]     Then, the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting is loaded in Step P 50 . Then, in Step P 51 , a switching signal is outputted to the valves  60 - 1  through  60 -M for the roller route switching air cylinder of the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting. Then, in Step P 52 , the first printing unit No. is deleted from the memory  40  for storing the printing unit No. for switching roller throw-on setting.  
         [0164]     Then, in Step P 53 , the contents of the memory  40  for storing the printing unit No. for switching roller throw-on setting are checked. Then, in Step P 54 , it is determined whether the stored printing unit No. is absent in the memory  40  for storing the printing unit No. for switching roller throw-on setting. If YES, 1 is written into the memory  46  for storing the count value M in Step P 55 . If NO, the program returns to Step P 50 .  
         [0165]     Then, in Step P 56 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 57 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 58 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 .  
         [0166]     Then, in Step P 59 , the opening amount Kmn 2  of the ink fountain key is transmitted to the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm. Then, if a reception confirmation signal is transmitted from the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm in Step P 60 , 1 is added to the count value N 2 , and written over the memory  52 , in Step P 61 .  
         [0167]     Then, in Step P 62 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 63 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and written over the memory  46 , in Step P 64 . If NO, the program returns to Step P 58 .  
         [0168]     Then, in Step P 65 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 66 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M in Step P 67 . If NO, the program returns to Step P 56 .  
         [0169]     Then, in Step P 68 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 69 , the reference rotation amount Rm of the ink fountain roller corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  41 . Then, in Step P 70 , the rotation amount Rm of the ink fountain roller is transmitted to the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm.  
         [0170]     Then, if a reception confirmation signal is transmitted from the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm in Step P 71 , 1 is added to the count value M, and the sum is written over the memory  46 , in Step P 72 . Then, in Step P 73 , the number Mmax of the printing units used in the coming printing is read from the memory  42 .  
         [0171]     Then, in Step P 74 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the program returns to Step P 1 . If NO, the program returns to Step P 68 . Thereafter, this procedure is repeated.  
         [0172]     The first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) act in accordance with action flows shown in  FIGS. 12   a  and  12   b.    
         [0173]     That is, if the opening amount Kmn 2  of the ink fountain key is transmitted from the ink supply amount control device  30  in Step P 1 , the opening amount Kmn of the ink fountain key is received, and stored in the memory  67  for storing the opening amount Kmn of the ink fountain key in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0174]     Then, in Step P 4 , the received opening amount Kmn of the ink fountain key is written into the memory  68  for storing the target ink fountain key opening amount. Then, in Step P 5 , the count value of the counter  77  is loaded. Then, in Step P 6 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0175]     Then, in Step P 7 , it is determined whether the target ink fountain key opening amount is equal to the current opening amount of the ink fountain key. If YES, the program returns to Step P 1 . If NO, it is determined in Step P 8  whether the target ink fountain key opening amount is larger than the current opening amount of the ink fountain key.  
         [0176]     If YES in Step P 8 , a command for normal rotation is outputted to the ink fountain key drive motor driver  75  in Step P 9 . If NO, a command for reverse rotation is outputted to the ink fountain key drive motor driver  75  in Step P 10 .  
         [0177]     Then, in Step P 11 , the count value of the counter  77  is loaded, and stored in the memory  69 . Then, in Step P 12 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0178]     Then, in Step P 13 , it is determined whether the current opening amount of the ink fountain key is equal to the target ink fountain key opening amount. If YES, a command for drive stop is outputted to the ink fountain key drive motor driver  75  in Step P 14 . Then, the program returns to Step P 1 . If NO, the program returns to Step P 11 . Thereafter, this procedure is repeated.  
         [0179]     The first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M act in accordance with an action flow shown in  FIG. 13 .  
         [0180]     That is, if the rotation amount Rm of the ink fountain roller is transmitted from the ink supply amount control device  30  in Step P 1 , the rotation amount Rm of the ink fountain roller is received, and stored in the memory  81  for storing the received rotation amount Rm of the ink fountain roller in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0181]     Then, in Step P 4 , the received rotation amount Rm of the ink fountain key is written into the memory  82  for storing the target ink fountain roller rotation amount, and stored. Then, in Step P 5 , the target rotation amount of the ink fountain roller is read from the memory  82 .  
         [0182]     Then, in Step P 6 , a rotational speed command on the target rotation amount of the ink fountain roller is outputted to the ink fountain roller drive motor driver  87 , and the program returns to Step P 1 . Thereafter, this procedure is repeated.  
         [0183]     In the present embodiment described above, as shown in  FIG. 4 , the image area rate (IRmn) in the range corresponding to each ink fountain key of each printing unit is found, and the difference Dt (IRm(n 1 - 1 )−IRmn 1 ) between the image area rates of the adjacent ink fountain keys is found. If this difference (absolute value) is equal to or greater than a certain value (first reference value R 1   m : first reference value in the claim) in even one of the ranges (see  FIG. 5   b ), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). If there is no such range (see  FIG. 5   a ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where color irregularities or the like minimally occur (i.e., second ink transport route).  
         [0184]     By so doing, the burden on the operator is lightened, and the rate of operation is increased. Furthermore, forgetting to do switching is avoided, thus eliminating a waste of printing material.  
         [0185]     If, in the present embodiment described above, the difference Dt (IRm(n 1 - 1 )−IRmn 1 ) between the image area rates of the adjacent ink fountain keys is equal to or greater than the certain value (first reference value R 1   m ), as shown in  FIG. 4 , the average of the image area rates (IRmn) of the entire image is obtained. Only when the obtained average value Dav (IRam) is equal to or greater than a certain value (second reference value R 2   m : second reference value in the claim), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). When the average value Dav is smaller than the certain value (second reference value R 2   m ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where the ink is minimally emulsified (i.e., second ink transport route).  
         [0186]     By so doing, the operator&#39;s judgment becomes unnecessary, the burden on the operator is lightened, the operator&#39;s mistake in switching is avoided, and the rate of operation is further increased. Also, a waste of printing material is eliminated further. In the above embodiment, the ink distribution roller  4   e  is thrown on the ink oscillating roller  5   b  when the image area rate difference Dt is equal to or greater than the first reference value and the average value Dav is equal to or greater than the second reference value. However, the ink distribution roller  4   e  may be thrown on the ink oscillating roller  5   b  when the image area rate difference Dt is greater than the first reference value and the average value Dav is greater than the second reference value.  
       Embodiment 2  
       [0187]      FIG. 14   a  is a block diagram of an ink supply amount control device showing Embodiment 2 of the present invention.  FIG. 14   b  is a block diagram of the ink supply amount control device.  FIG. 15  is a block diagram of an ink fountain key opening amount control device in Embodiment 2.  FIG. 16  is a block diagram of an ink fountain roller rotation amount control device in Embodiment 2.  FIG. 17   a  is an action flow chart of the ink supply amount control device.  FIG. 17   b  is an action flow chart of the ink supply amount control device.  FIG. 17   c  is an action flow chart of the ink supply amount control device.  FIG. 18   a  is an action flow chart of the ink supply amount control device.  FIG. 18   b  is an action flow chart of the ink supply amount control device.  FIG. 18   c  is an action flow chart of the ink supply amount control device.  FIG. 19   a  is an action flow chart of the ink supply amount control device.  FIG. 19   b  is an action flow chart of the ink supply amount control device.  FIG. 20   a  is an action flow chart of the ink fountain key opening amount control device.  FIG. 20   b  is an action flow chart of the ink fountain key opening amount control device.  FIG. 21  is an action flow chart of the ink fountain roller rotation amount control device.  
         [0188]     The configuration of the switching means for the ink transport route in the present embodiment is the same as that in Embodiment 1. Thus, duplicate explanations will be omitted by reference to FIGS.  1  to  3 .  
         [0189]     The ink supply amount control device  30  of the present embodiment comprises CPU  31 , RAM  32 , ROM  33 , an input/output device  53 , an input/output device  54 , an interface  55 , and the following memories connected by a bus-line (BUS)  56 , as shown in  FIGS. 14   a  and  14   b : A memory  36  for storing a second reference value R 2   m  for switching corresponding to each ink color ICm; a memory  37  for storing a printing unit No. for switching roller throw-on; a memory  38  for storing an image area rate-ink fountain key opening amount conversion table corresponding to each ink color ICm; a memory  39  for storing the ink fountain key opening amount Kmn 2  of each printing unit used in the coming printing; a memory  40  for storing a printing unit No. for switching roller throw-on setting; a memory  41  for storing a reference ink fountain roller rotation amount Rm corresponding to each ink color ICm; a memory  42  for storing the number Mmax of the printing units used in the coming printing; a memory  43  for storing the No. UNm of a printing unit used in the coming printing; a memory  44  for storing the ink color ICm of each printing unit UNm used in the coming printing; a memory  45  for storing an image area rate IRmn in a range corresponding to each ink fountain key of each printing unit UNm used in the coming printing; a memory  46  for storing a count value M; a memory  47  for storing a count value N 1 ; a memory  50  for storing a first reference value R 1   m  for switching corresponding to each ink color ICm; a memory  51  for storing the total number Nmax of the ink fountain keys of each printing unit; a memory  52  for storing a count value N 2 ; a memory  91  for storing the average value IAam of the image areas of the respective printing units used in the coming printing; a memory  92  for storing the area IAmax in a range corresponding to the ink fountain key; a memory  93  for storing an image area IAmn in a range corresponding to each ink fountain key of each printing unit UNm used in the coming printing; a memory  94  for storing the difference (IAm(n 1 - 1 )−IAmn 1 ) between an image area IAm(n 1 - 1 ) in a range corresponding to the (N 1 - 1 )th ink fountain key and an image area IAmn 1  in a range corresponding to the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing; a memory  95  for storing the absolute value |IAm(n 1 - 1 )−IAmn 1 | of the difference between the image area rate IAm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key and the image area rate IAmn 1  in the range corresponding to the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing; and a memory  96  for storing the total value IAs of the image areas of the respective printing units used in the coming printing.  
         [0190]     An input device  57 , such as a keyboard, various switches, and a button, a display device  58 , such as CRT and a lamp, and an output device  59 , such as an F-D drive, and a printer, are connected to the input/output device  53 . To the input/output device  54 , there are connected a valve  60 - 1  for an air cylinder for switching the roller route of the first printing unit through a valve  60 -M for an air cylinder for switching the roller route of the Mth printing unit corresponding to the air cylinder  25 - 1  for switching the roller route of the first printing unit through the air cylinder  25 -M for switching the roller route of the Mth printing unit.  
         [0191]     To the interface  55 , there are connected a printing press control device  61 , a first (first printing unit) ink fountain roller rotation amount control device  63 - 1  through an Mth (Mth printing unit) ink fountain roller rotation amount control device  63 -M, and a first ink fountain key opening amount control device  62 - 1  through an (M×N)th ink fountain key opening amount control device  62 -(M×N).  
         [0192]     The printing press control device  61  controls the entire printing press, including a feeding unit, first to Mth printing units, and a delivery unit which are not shown.  
         [0193]     As shown in  FIG. 15 , the first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) comprise the following: CPU  64 , RAM  65 , ROM  66 , and a memory  67  for storing a received ink fountain key opening amount Kmn, a memory  68  for storing a target ink fountain key opening amount, a memory  69  for storing the count value of a counter, and a memory  70  for storing a current ink fountain key opening amount are connected via a bus-line (BUS)  73  together with an input/output device  71  and an interface  72 .  
         [0194]     To the input/output device  71 , an ink fountain key drive motor  74  is connected via an ink fountain key drive motor driver  75 , and an ink fountain key drive motor rotary encoder  76  incorporated in the ink fountain key drive motor  74  is connected via a counter  77 . A detection signal from the ink fountain key drive motor rotary encoder  76  is inputted into the ink fountain key drive motor driver  75 . The aforementioned ink supply amount control device  30  is connected to the interface  72 .  
         [0195]     As shown in  FIG. 16 , the first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M comprise CPU  78 , RAM  79 , ROM  80 , and a memory  81  for storing a received ink fountain roller rotation amount Rm, and a memory  82  for storing a target ink fountain roller rotation amount connected via a bus-line (BUS)  85  together with an input/output device  83  and an interface  84 .  
         [0196]     To the input/output device  83 , an ink fountain roller drive motor  86  is connected via an ink fountain roller drive motor driver  87 , and an ink fountain roller drive motor rotary encoder  88  incorporated in the ink fountain roller drive motor  86  is connected via an F/V converter  89  and an A/D converter  90 . A detection signal from the ink fountain roller drive motor rotary encoder  88  is inputted into the ink fountain roller drive motor driver  87 . The aforementioned ink supply amount control device  30  is connected to the interface  84 .  
         [0197]     Because of the above configuration, the ink supply amount control device  30  acts in accordance with action flows shown in  FIGS. 17   a  through  17   c ,  FIGS. 18   a  to  18   c , and  FIGS. 19   a  and  19   b.    
         [0198]     That is, it is determined in Step P 1  whether an ink preset switch in the input/output device  57  is ON or not. If ON, each memory is initialized in Step P 2 . If not ON, it is determined in Step P 3  whether a printing completion signal has been outputted from the printing press control device  61 . If YES, outputting of a switching signal to the valves  60 - 1  through  60 -M for air cylinders for switching the roller routes of all printing units is stopped in Step P 4 , and the program returns to Step P 1 . If NO, the program immediately returns to Step P 1 .  
         [0199]     Then, in Step P 5 , the number Mmax of the printing units used in the coming printing, the printing unit No. UNm, the ink color ICm of each printing unit UNm, and the image area IAmn in a range corresponding to each ink fountain key are inputted, and stored into the memories  42  to  44  and  93 . Then, in Step P 6 , 1 is written into the memory  46  for storing the count value M. In Step P 7 , 2 is written into the memory  47  for storing the count value N 1 .  
         [0200]     Then, in Step P 8 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 9 , the image area IAm(n 1 - 1 ) in a range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  93 . Also, in Step P 10 , the image area IAmn 1  in a range corresponding to the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  93 .  
         [0201]     Then, in Step P 11 , the difference (IAm(n 1 - 1 )−IAmn 1 ) between the image area IAm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area IAmn 1  in the range corresponding to the N 1 th ink fountain key is computed, and stored into the memory  94 . In Step P 12 , the absolute value |IAm(n 1 - 1 )−IAmn 1 | of the difference between the image area IAm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area IAmn 1  in the range corresponding to the N 1 th ink fountain key is computed, and stored into the memory  95 .  
         [0202]     Then, in Step P 13 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Also, in Step P 14 , the first reference value R 1   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  50 . Then, in Step P 15 , it is determined whether the absolute value |IAm(n 1 - 1 )−IAmn 1 | of the difference between the image area IAm(n 1 - 1 ) in the range corresponding to the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the image area IAmn 1  in the range corresponding to the N 1 th ink fountain key is equal to or larger than the first reference value R 1   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0203]     If YES in Step P 15 , the program shifts to Step P 22  to be described later. IF NO in Step P 15 , 1 is added to the count value N 1 , and the sum is written over the memory  47 , in Step P 16 .  
         [0204]     Then, in Step P 17 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 18 , it is determined whether the count value N 1  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M in Step P 19 , and the sum is written over the memory  46 . If NO, the program returns to Step P 9 .  
         [0205]     Then, in Step P 20 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 21 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the program shifts to Step P 36  to be described later. If NO, the program returns to Step P 7 .  
         [0206]     Then, in Step P 22 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 23 , the memory  96  for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing is initialized. Then, in Step P 24 , the image area IAmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  93 .  
         [0207]     Then, in Step P 25 , the value of the memory  96  for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing is loaded. Then, in Step P 26 , the image area IAmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is added to the value of the memory  96  for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing, and the sum is written over the memory  96  for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing.  
         [0208]     Then, in Step P 27 , 1 is added into the memory  52  for storing the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 28 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 29 , it is determined whether the count value N 2  is equal to or larger than the total number Nmax of the ink fountain keys of each printing unit.  
         [0209]     Then, in Step P 30 , the value of the memory  96  for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing is loaded. Then, in Step P 31 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 32 , the value of the memory for storing the total value IAs of the image areas of the printing unit UNm used in the coming printing is divided by the total number Nmax of the ink fountain keys of each printing unit to obtain the average value IAam of the image areas of the Mth printing unit UNm used in the coming printing, and this average value IAam is stored in the memory  91 .  
         [0210]     Then, in Step P 33 , the second reference value R 2   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  36 . Then, in Step P 34 , it is determined whether the average value IAam of the image areas of the Mth printing unit UNm used in the coming printing is equal to or greater than the second reference value R 2   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0211]     If YES in Step P 34 , the No. UNm of the Mth printing unit used in the coming printing is written into the memory  37  for storing the printing unit No. for switching roller throw-on in Step P 35 . Then, the program returns to Step P 19 . If NO in Step P 34 , the program returns to Step P 16 .  
         [0212]     If YES in Step P 21 , 1 is written into the memory  46  for storing the count value M in Step P 36 , and 1 is written into the memory  52  for storing the count value N 2  in Step P 37 . Then, in Step P 38 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 .  
         [0213]     Then, in Step P 39 , the area IAmax in a range corresponding to the ink fountain keys is read from the memory  92 . In Step P 40 , the image area IAmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  93 .  
         [0214]     Then, in Step P 41 , the image area IAmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is divided by the area IAmax in the range corresponding to the ink fountain keys to compute the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing, and the result is stored in the memory  45 . Then, in Step P 42 , 1 is added to the count value N 2 , and written over the memory  52 .  
         [0215]     Then, in Step P 43 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 44 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and written over the memory  46 , in Step P 45  If NO, the program returns to Step P 39 .  
         [0216]     Then, in Step P 46 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 47 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M, in Step P 48 . If NO, the program returns to Step P 37 .  
         [0217]     Then, in Step P 49 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 50 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 .  
         [0218]     Then, in Step P 51 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 52 , the image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  38 . Then, in Step P 53 , the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 .  
         [0219]     Then, in Step P 54 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is found from the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing by use of the image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the printing unit UNm used in the coming printing, and the result is stored in the memory  39 .  
         [0220]     Then, in Step P 55 , 1 is added to the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 56 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 , and in Step P 57 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color.  
         [0221]     If YES in Step P 57 , 1 is added to the count value M, and the sum is written over the memory  46  in Step P 58 . If NO in Step P 57 , the program returns to Step P 51 .  
         [0222]     Then, in Step P 59 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 60 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the contents of the memory  37  for storing the No. of the printing unit for switching roller throw-on are written, in Step P 61 , into the memory  40  for storing the No. of the printing unit for setting switching roller throw-on. If NO, the program returns to Step P 49 .  
         [0223]     Then, the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting is loaded in Step P 62 . Then, in Step P 63 , a switching signal is outputted to the valves  60 - 1  through  60 -M for the roller route switching air cylinder of the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting. Then, in Step P 64 , the first printing unit No. is deleted from the memory  40  for storing the printing unit No. for switching roller throw-on setting.  
         [0224]     Then, in Step P 65 , the contents of the memory  40  for storing the printing unit No. for switching roller throw-on setting are checked. Then, in Step P 66 , it is determined whether the stored printing unit No. is absent in the memory  40  for storing the printing unit No. for switching roller throw-on setting. If YES, 1 is written into the memory  46  for storing the count value M in Step P 67 . If NO, the program returns to Step P 62 .  
         [0225]     Then, in Step P 68 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 69 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 70 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 .  
         [0226]     Then, in Step P 71 , the opening amount Kmn 2  of the ink fountain key is transmitted to the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm. Then, if a reception confirmation signal is transmitted from the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm in Step P 72 , 1 is added to the count value N 2 , and written over the memory  52 , in Step P 73 .  
         [0227]     Then, in Step P 74 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 75 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and written over the memory  46 , in Step P 76 . If NO, the program returns to Step P 70 .  
         [0228]     Then, in Step P 77 , the number Nmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 78 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M in Step P 79 . If NO, the program returns to Step P 68 .  
         [0229]     Then, in Step P 80 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 81 , the reference rotation amount Rm of the ink fountain roller corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  41 . Then, in Step P 82 , the rotation amount Rm of the ink fountain roller is transmitted to the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm.  
         [0230]     Then, if a reception confirmation signal is transmitted from the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm in Step P 83 , 1 is added to the count value M, and the sum is written over the memory  46 , in Step P 84 . Then, in Step P 85 , the number Mmax of the printing units used in the coming printing is read from the memory  42 .  
         [0231]     Then, in Step P 86 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the program returns to Step P 1 . If NO, the program returns to Step P 80 . Thereafter, this procedure is repeated.  
         [0232]     The first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) also act in accordance with action flows shown in  FIGS. 20   a  and  20   b.    
         [0233]     That is, if the opening amount Kmn 2  of the ink fountain key is transmitted from the ink supply amount control device  30  in Step P 1 , the opening amount Kmn of the ink fountain key is received, and stored in the memory  67  for storing the opening amount Kmn of the ink fountain key in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0234]     Then, in Step  4 , the received opening amount Kmn of the ink fountain key is written into the memory  68  for storing the target ink fountain key opening amount. Then, in Step P 5 , the count value of the counter  77  is loaded, and stored into the memory  69 . Then, in Step P 6 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0235]     Then, in Step P 7 , it is determined whether the target ink fountain key opening amount is equal to the current opening amount of the ink fountain key. If YES, the program returns to Step P 1 . If NO, it is determined in Step P 8  whether the target ink fountain key opening amount is larger than the current opening amount of the ink fountain key.  
         [0236]     If YES in Step P 8 , a command for normal rotation is outputted to the ink fountain key drive motor driver  75  in Step P 9 . If NO, a command for reverse rotation is outputted to the ink fountain key drive motor driver  75  in Step P 10 .  
         [0237]     Then, in Step P 11 , the count value of the counter  77  is loaded, and stored in the memory  69 . Then, in Step P 12 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0238]     Then, in Step P 13 , it is determined whether the current opening amount of the ink fountain key is equal to the target ink fountain key opening amount. If YES, a command for drive stop is outputted to the ink fountain key drive motor driver  75  in Step P 14 . Then, the program returns to Step P 1 . If NO, the program returns to Step P 11 . Thereafter, this procedure is repeated.  
         [0239]     The first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M act in accordance with an action flow shown in  FIG. 21 .  
         [0240]     That is, if the rotation amount Rm of the ink fountain roller is transmitted from the ink supply amount control device  30  in Step P 1 , the rotation amount Rm of the ink fountain roller is received, and stored in the memory  81  for storing the received rotation amount Rm of the ink fountain roller in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0241]     Then, in Step P 4 , the received rotation amount Rm of the ink fountain key is written into the memory  82  for storing the target ink fountain roller rotation amount, and stored. Then, in Step P 5 , the target rotation amount of the ink fountain roller is read from the memory  82 .  
         [0242]     Then, in Step P 6 , a rotational speed command on the target rotation amount of the ink fountain roller is outputted to the ink fountain roller drive motor driver  87 , and the program returns to Step P 1 . Thereafter, this procedure is repeated.  
         [0243]     In the present embodiment, as described above, the image area (IAmn) in the range corresponding to each ink fountain key of each printing unit is found, and the difference (IAm(n 1 - 1 )−IAmn 1 ) between the image areas of the adjacent ink fountain keys is found. If this difference (absolute value) is equal to or greater than a certain value (first reference value R 1   m : first reference value in the claim) in even one of the ranges, the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). If there is no such range, on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where color irregularities or the like minimally occur (i.e., second ink transport route).  
         [0244]     By so doing, the burden on the operator is lightened, and the rate of operation is increased. Furthermore, forgetting to do switching is avoided, thus eliminating a waste of printing material.  
         [0245]     If, in the present embodiment, the difference (IAm(n 1 - 1 )−IAmn 1 ) between the image area rates of the adjacent ink fountain keys is equal to or greater than the certain value (first reference value R 1   m ), the average of the image areas (IAmn) of the entire image is further obtained. Only when the obtained average value (IAam) is equal to or greater than a certain value (second reference value R 2   m : second reference value in the claim), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). When the average value is smaller than the certain value (second reference value R 2   m ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  oil the dampening side, thus establishing the ink transport route where the ink is minimally emulsified (i.e., second ink transport route). Furthermore, the average value (IAam) of the image areas (IAmn) is the value obtained by dividing the total value (IAs) of the image areas by the total number Nmax of the ink fountain keys of the respective printing units. Since the total number Nmax of the ink fountain keys of the respective printing units is a constant value, it goes without saying that the total value (IAs) may be obtained instead of the average value (IAam) of the image areas (IAmn), and this total value (IAs) may be compared with the certain value (second reference value R 2   m ).  
         [0246]     By so doing, the operator&#39;s judgment becomes unnecessary, the burden on the operator is lightened, the operator&#39;s mistake in switching is avoided, and the rate of operation is further increased. Also, a waste of printing material is eliminated further. In the above embodiment, moreover, the ink distribution roller  4   e  is thrown oil the ink oscillating roller  5   b  when the image area rate difference Dt is equal to or greater than the first reference value and the average value Dav is equal to or greater than the second reference value. However, the ink distribution roller  4   e  may be thrown on the ink oscillating roller  5   b  when the image area rate difference Dt is greater than the first reference value and the average value Dav is greater than the second reference value.  
       Embodiment 3  
       [0247]      FIG. 22   a  is a block diagram of an ink supply amount control device showing Embodiment 3 of the present invention.  FIG. 22   b  is a block diagram of the ink supply amount control device.  FIG. 23  is a block diagram of an ink fountain key opening amount control device in Embodiment 3.  FIG. 24  is a block diagram of an ink fountain roller rotation amount control device in Embodiment 3.  FIG. 25   a  is an action flow chart of the ink supply amount control device.  FIG. 25   b  is an action flow chart of the ink supply amount control device.  FIG. 25   c  is an action flow chart of the ink supply amount control device.  FIG. 25   d  is an action flow chart of the ink supply amount control device.  FIG. 25   e  is an action flow chart of the ink supply amount control device.  FIG. 26   a  is an action flow chart of the ink supply amount control device.  FIG. 26   b  is an action flow chart of the ink supply amount control device.  FIG. 26   c  is an action flow chart of the ink supply amount control device.  FIG. 27   a  is an action flow chart of the ink fountain key opening amount control device.  FIG. 27   b  is an action flow chart of the ink fountain key opening amount control device.  FIG. 28  is an action flow chart of the ink fountain roller rotation amount control device.  
         [0248]     The configuration of the switching means for the ink transport route in the present embodiment is the same as that in Embodiment 1. Thus, duplicate explanations are omitted by reference to FIGS.  1  to  3 .  
         [0249]     The ink supply amount control device  30  of the present embodiment comprises CPU  31 , RAM  32 , ROM  33 , an input/output device  53 , an input/output device  54 , an interface  55 , and the following memories connected by a bus-line (BUS)  56 , as shown in  FIGS. 22   a  and  22   b : A memory  36  for storing a second reference value R 2   m  for switching corresponding to each ink color ICm; a memory  37  for storing a printing unit No. for switching roller throw-on; a memory  38  for storing an image area rate-ink fountain key opening amount conversion table corresponding to each ink color ICm; a memory  39  for storing the ink fountain key opening amount Kmn 2  of each printing unit used in the coming printing; a memory  40  for storing a printing unit No. for switching roller throw-on setting; a memory  41  for storing a reference ink fountain roller rotation amount Rm corresponding to each ink color ICm; a memory  42  for storing the number Mmax of the printing units used in the coming printing; a memory  43  for storing the No. UNm of a printing unit used in the coming printing; a memory  44  for storing the ink color ICm of each printing unit UNm used in the coming printing; a memory  45  for storing an image area rate IRmn in a range corresponding to each ink fountain key of each printing unit UNm used in the coming printing; a memory  46  for storing a count value M; a memory  47  for storing a count value N 1 ; a memory  50  for storing a first reference value R 1   m  for switching corresponding to each ink color ICm; a memory  51  for storing the total number Nmax of the ink fountain keys of each printing unit; a memory  52  for storing a count value N 2 ; a memory  97  for storing the total value Ks of the ink fountain keys of each printing unit used in the coming printing; a memory  98  for storing the average value Kam of the ink fountain keys of the respective printing units used in the coming printing; a memory  99  for storing the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key and the opening amount Kmn 1  of the N 1 th ink fountain key of each printing unit UNm used in the coming printing; and a memory  100  for storing the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key and the opening amount Kmn 1  of the N 1 th ink fountain key of each printing unit UNm used in the coining printing.  
         [0250]     An input device  57 , such as a keyboard, various switches, and a button, a display device  58 , such as CRT and a lamp, and an output device  59 , such as an F-D drive, and a printer, are connected to the input/output device  53 . To the input/output device  54 , there are connected a valve  60 - 1  for an air cylinder for switching the roller route of the first printing unit through a valve  60 -M for an air cylinder for switching the roller route of the Mth printing unit corresponding to the air cylinder  25 - 1  for switching the roller route of the first printing unit through the air cylinder  25 -M for switching the roller route of the Mth printing unit.  
         [0251]     To the interface  55 , there are connected a printing press control device  61 , a first (first printing unit) ink fountain roller rotation amount control device  63 - 1  through an Mth (Mth printing unit) ink fountain roller rotation amount control device  63 -M, and a first ink fountain key opening amount control device  62 - 1  through an (M×N)th ink fountain key opening amount control device  62 -(M×N).  
         [0252]     The printing press control device  61  controls the entire printing press, including a feeding unit, first to Mth printing units, and a delivery unit which are not shown.  
         [0253]     As shown in  FIG. 23 , the first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) comprise the following: CPU  64 , RAM  65 , ROM  66 , and a memory  67  for storing a received ink fountain key opening amount Kmn, a memory  68  for storing a target ink fountain key opening amount, a memory  69  for storing the count value of a counter, and a memory  70  for storing a current ink fountain key opening amount are connected via a buts-line (BUS)  73  together with an input/output device  71  and an interface  72 .  
         [0254]     To the input/output device  71 , an ink fountain key drive motor  74  is connected via an ink fountain key drive motor driver  75 , and an ink fountain key drive motor rotary encoder  76  incorporated in the ink fountain key drive motor  74  is connected via a counter  77 . A detection signal from the ink fountain key drive motor rotary encoder  76  is inputted into the ink fountain key drive motor driver  75 . The aforementioned ink supply amount control device  30  is connected to the interface  72 .  
         [0255]     As shown in  FIG. 24 , the first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M comprise CPU  78 , RAM  79 , ROM  80 , and a memory  81  for storing a received ink fountain roller rotation amount Rm, and a memory  82  for storing a target ink fountain roller rotation amount connected via a bus-line (BUS)  85  together with an input/output device  83  and an interface  84 .  
         [0256]     To the input/output device  83 , an ink fountain roller drive motor  86  is connected via an ink fountain roller drive motor driver  87 , and an ink fountain roller drive motor rotary encoder  88  incorporated in the ink fountain roller drive motor  86  is connected via an F/V converter  89  and an A/D converter  90 . A detection signal from the ink fountain roller drive motor rotary encoder  88  is inputted into the ink fountain roller drive motor driver  87 . The aforementioned ink supply amount control device  30  is connected to the interface  84 .  
         [0257]     Because of the above configuration, the ink supply amount control device  30  acts in accordance with action flows shown in  FIGS. 25   a  through  25   e  and  FIGS. 26   a  to  26   c.    
         [0258]     That is, it is determined in Step P 1  whether an ink preset switch in the input/output device  57  is ON or not. If ON, each memory is initialized in Step P 2 . If not ON, it is determined in Step P 3  whether a printing completion signal has been outputted from the printing press control device  61 . If YES, outputting of a switching signal to the valves  60 - 1  through  60 -M for air cylinders for switching the roller routes of all printing units is stopped in Step P 4 , and the program returns to Step P 1 . If NO, the program immediately returns to Step P 1 .  
         [0259]     Then, in Step P 5 , the number Mmax of the printing units used in the coming printing, the printing unit No. UNm, the ink color ICm of each printing unit UNm, and the image area rate IRmn in a range corresponding to each ink fountain key are inputted, and stored into the memories  42  to  45 . Then, in Step P 6 , 1 is written into the memory  46  for storing the count value M. In Step P 7 , 1 is written into the memory  52  for storing the count value N 2 .  
         [0260]     Then, in Step P 8 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 9 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 10 , an image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  38 .  
         [0261]     Then, in Step P 11 , an image area rate IRmn 2  in a range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  45 . Then, in Step P 12 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is found from the image area rate IRmn 2  in the range corresponding to the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing by use of the image area rate-ink fountain key opening amount conversion table corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing, and the opening amount Kmn 2  is stored in the memory  39 .  
         [0262]     Then, in Step P 13 , 1 is added to the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 14 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 , and in Step P 15 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color.  
         [0263]     If YES in Step P 15 , 1 is added to the count value M, and the sum is written over the memory  46  in Step P 16 . If NO in Step P 15 , the program returns to Step P 9 .  
         [0264]     Then, in Step P 17 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 18 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M, in Step P 19 . If NO, the program returns to Step P 7 .  
         [0265]     Then, in Step P 20 , 2 is written into the memory  47  for storing the count value N 1 . Then, in Step P 21 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 22 , the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 .  
         [0266]     Then, in Step P 23 , the opening amount Kmn 1  of the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 . Then, in Step P 24 , the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is computed, and stored into the memory  99 .  
         [0267]     Then, in Step P 25 , the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is computed, and stored into the memory  100 . Then, in Step P 26 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 .  
         [0268]     Then, in Step P 27 , the first reference value R 1   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  50 . Then, in Step P 28 , it is determined whether the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is equal to or larger than the first reference value R 1   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0269]     If YES in Step P 28 , 1 is written into the memory  52  for storing the count value N 2  in Step P 29 . If NO, the program shifts to Step P 43  to be described later.  
         [0270]     Then, in Step P 30 , the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is initialized. Then, in Step P 31 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 . Then, in Step P 32 , the value of the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is loaded.  
         [0271]     Then, in Step P 33 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is added to the value of the memory for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing, and the sum is written over the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing. Then, in Step P 34 , 1 is added to the count value N 2 , and the sum is written over the memory  52 .  
         [0272]     Then, in Step P 35 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 36 , it is determined whether the count value N 2  is equal to or greater than the total number Nmax of the ink fountain keys of each printing unit. If YES, the value of the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is loaded in Step P 37 . If NO, the program returns to Step P 31 .  
         [0273]     Then, in Step P 38 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 39 , the value of the memory for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is divided by the total number Nmax of the ink fountain keys of each printing unit to obtain the average value Kam of the opening amounts of the ink fountain keys of the Mth printing unit UNm used in the coming printing, and the average value Kam is stored in the memory  98 .  
         [0274]     Then, in Step P 40 , the second reference value R 2   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  36 . Then, in Step P 41 , it is determined whether the average value Kam of the opening amounts of the ink fountain keys of the Mth printing unit UNm used in the coming printing is equal to or greater than the second reference value R 2   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0275]     If YES in Step P 41 , the No. UNm of the Mth printing unit used in the coming printing is written into the memory  37  for storing the printing unit No. for switching roller throw-on in Step P 42 . Then, the program shifts to Step P 46  to be described later. If NO, 1 is added to the count value N 1 , and the sum is written over the memory  47 , in Step P 43 .  
         [0276]     Then, in Step P 44 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 45 , it is determined whether the count value N 1  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and the sum is written over the memory  46 , in Step P 46 . If NO, the program returns to Step P 22 .  
         [0277]     Then, in Step P 47 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 48 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the contents of the memory  37  for storing the printing unit No. for switching roller throw-on are written into the memory  40  for storing the printing unit No. for switching roller throw-on setting in Step P 49 . If NO, the program returns to Step P 20 .  
         [0278]     Then, the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting is loaded in Step P 50 . Then, in Step P 51 , a switching signal is outputted to the valves  60 - 1  through  60 -M for the roller route switching air cylinders of the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting. Then, in Step P 52 , the first printing unit No. is deleted from the memory  40  for storing the printing unit No. for switching roller throw-on setting.  
         [0279]     Then, in Step P 53 , the contents of the memory  40  for storing the printing unit No. for switching roller throw-on setting are checked. Then, in Step P 54 , it is determined whether the stored printing unit No. is absent in the memory  40  for storing the printing unit No. for switching roller throw-on setting. If YES, 1 is written into the memory  46  for storing the count value M in Step P 55 . If NO, the program returns to Step P 50 .  
         [0280]     Then, in Step P 56 , 1 is written into the memory  52  for storing the count value N 2 . Then, in Step P 57 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 58 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 .  
         [0281]     Then, in Step P 59 , the opening amount Kmn 2  of the ink fountain key is transmitted to the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm. Then, if a reception confirmation signal is transmitted from the N 2 th ink fountain key opening amount control devices  62 - 1  through  62 -(M×N) of the printing unit of the printing unit No. UNm in Step P 60 , 1 is added to the count value N 2 , and written over the memory  52 , in Step P 61 .  
         [0282]     Then, in Step P 62 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 63 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and written over the memory  46 , in Step P 64 . If NO, the program returns to Step P 58 .  
         [0283]     Then, in Step P 65 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 66 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M in Step P 67 . If NO, the program returns to Step P 56 .  
         [0284]     Then, in Step P 68 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 . Then, in Step P 69 , the reference rotation amount Rm of the ink fountain roller corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  41 . Then, in Step P 70 , the rotation amount Rm of the ink fountain roller is transmitted to the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm.  
         [0285]     Then, if a reception confirmation signal is transmitted from the ink fountain roller rotation amount control devices  63 - 1  through  63 -M of the printing unit of the printing unit No. UNm in Step P 71 , 1 is added to the count value M, and the sum is written over the memory  46 , in Step P 72 . Then, in Step P 73 , the number Mmax of the printing units used in the coming printing is read from the memory  42 .  
         [0286]     Then, in Step P 74 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the program returns to Step P 1 . If NO, the program returns to Step P 68 . Thereafter, this procedure is repeated.  
         [0287]     The first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) also act in accordance with action flows shown in  FIGS. 27   a  and  27   b.    
         [0288]     That is, if the opening amount Kmn 2  of the ink fountain key is transmitted from the ink supply amount control device  30  in Step P 1 , the opening amount Kmn of the ink fountain key is received, and stored in the memory  67  for storing the opening amount Kmn of the ink fountain key in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0289]     Then, in Step P 4 , the received opening amount Kmn of the ink fountain key is written into the memory  68  for storing the target ink fountain key opening amount. Then, in Step P 5 , the count value of the counter  77  is loaded, and stored into the memory  69 . Then, in Step P 6 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0290]     Then, in Step P 7 , it is determined whether the target ink fountain key opening amount is equal to the current opening amount of the ink fountain key. If YES, the program returns to Step P 1 . If NO, it is determined in Step P 8  whether the target ink fountain key opening amount is larger than the current opening amount of the ink fountain key.  
         [0291]     If YES in Step P 8 , a command for normal rotation is outputted to the ink fountain key drive motor driver  75  in Step P 9 . If NO, a command for reverse rotation is outputted to the ink fountain key drive motor driver  75  in Step P 10 .  
         [0292]     Then, in Step P 11 , the count value of the counter  77  is loaded, and stored in the memory  69 . Then, in Step P 12 , the current opening amount of the ink fountain key is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0293]     Then, in Step P 13 , it is determined whether the current opening amount of the ink fountain key is equal to the target ink fountain key opening amount. If YES, a command for drive stop is outputted to the ink fountain key drive motor driver  75  in Step P 14 . Then, the program returns to Step P 1 . If NO, the program returns to Step P 11 . Thereafter, this procedure is repeated.  
         [0294]     The first ink fountain roller rotation amount control device  63 - 1  through the Mth ink fountain roller rotation amount control device  63 -M act in accordance with an action flow shown in  FIG. 28 .  
         [0295]     That is, if the rotation amount Rm of the ink fountain roller is transmitted from the ink supply amount control device  30  in Step P 1 , the rotation amount Rm of the ink fountain roller is received, and stored in the memory  81  for storing the received rotation amount Rm of the ink fountain roller in Step P 2 . Then, in Step P 3 , a reception confirmation signal is transmitted to the ink supply amount control device  30 .  
         [0296]     Then, in Step P 4 , the received rotation amount Rm of the ink fountain key is written into the memory  82  for storing the target ink fountain roller rotation amount, and stored. Then, in Step P 5 , the target rotation amount of the ink fountain roller is read from the memory  82 .  
         [0297]     Then, in Step P 6 , a rotational speed command on the target rotation amount of the ink fountain roller is outputted to the ink fountain roller drive motor driver  87 , and the program returns to Step P 1 . Thereafter, this procedure is repeated.  
         [0298]     In the present embodiment, as described above, the opening amount (Kmn) of each ink fountain key of each printing unit is found, and the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amounts of the adjacent ink fountain keys is found. If this difference (absolute value) is equal to or greater than a certain value (first reference value R 1   m : third reference value in the claim) in even one of the ranges (see  FIG. 5   b ), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). If there is no such range (see  FIG. 5   a ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where color irregularities or the like minimally occur (i.e., second ink transport route).  
         [0299]     By so doing, the burden on the operator is lightened, and the rate of operation is increased. Furthermore, forgetting to do switching is avoided, thus eliminating a waste of printing material.  
         [0300]     If, in the present embodiment, the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amounts of the adjacent ink fountain keys is equal to or greater than the certain value (first reference value R 1   m ), the average of the opening amounts of the respective ink fountain keys is obtained. Only when the obtained average value (Kam) is equal to or greater than a certain value (second reference value R 2   m : fourth reference value in the claim), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). When the average value is smaller than the certain value (second reference value R 2   m ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where the ink is minimally emulsified (i.e., second ink transport route). Furthermore, the average value (Kam) of the opening amounts of the ink fountain keys is the value obtained by dividing the total value (Ks) of the opening amounts of the ink fountain keys by the total number Nmax of the ink fountain keys of the respective printing units. Since the total number Nmax of the ink fountain keys of the respective printing units is a constant value, it goes without saying that the total value (Ks) may be obtained instead of the average value (Kam) of the opening amounts (Kmn) of the ink fountain keys, and this total value (Ks) may be compared with the certain value (second reference value R 2   m ).  
         [0301]     By so doing, the operator&#39;s judgment becomes unnecessary, the burden on the operator is lightened, the operator&#39;s mistake in switching is avoided, and the rate of operation is further increased. Also, a waste of printing material is eliminated further. In the above embodiment, moreover, the ink distribution roller  4   e  is thrown on the ink oscillating roller  5   b  when the opening amount difference (Km(n 1 - 1 )−Kmn 1 ) is equal to or greater than the first reference value and the average value (Kam) is equal to or greater than the second reference value. However, the ink distribution roller  4   e  may be thrown on the ink oscillating roller  5   b  when the opening amount difference (Km(n 1 - 1 )−Kmn 1 ) of the ink fountain key is greater than the first reference value and the average value (Kam) is greater than the second reference value.  
       Embodiment 4  
       [0302]      FIG. 29   a  is a block diagram of a switching control device showing Embodiment 4 of the present invention.  FIG. 29   b  is a block diagram of the switching control device.  FIG. 30  is a block diagram of an ink fountain key opening amount control device in Embodiment 4.  FIG. 31   a  is an action flow chart of the switching control device.  FIG. 31   b  is an action flow chart of the switching control device.  FIG. 31   c  is an action flow chart of the switching control device.  FIG. 31   d  is an action flow chart of the switching control device.  FIG. 31   e  is an action flow chart of the switching control device.  FIG. 32  is an action flow chart of the switching control device.  FIG. 33  is an action flow chart of the ink fountain key opening amount control device.  
         [0303]     In the present embodiment, the configuration of the switching means for the ink transport route is the same as that in Embodiment 1, except that the roller route switching air cylinders  25 - 1  to  25 -M of the first to Mth printing units in Embodiment 1 are driven and controlled by a switching control device  30 A to be described later. Thus, duplicate explanations will be omitted by reference to FIGS.  1  to  3 .  
         [0304]     The switching control device  30 A of the present embodiment comprises CPU  31 , RAM  32 , ROM  33 , an input/output device  53 , an input/output device  54 , an interface  55 , and the following memories connected by a bus-line (BUS)  56 , as shown in  FIGS. 29   a  and  29   b : A memory  36  for storing a second reference value R 2   m  for switching corresponding to each ink color ICm; a memory  37  for storing a printing unit No. for switching roller throw-on; a memory  39  for storing the ink fountain key opening amount Kmn 2  of each printing unit used in the coming printing; a memory  40  for storing a printing unit No. for switching roller throw-on setting; a memory  42  for storing the number Mmax of the printing units used in the coming printing; a memory  43  for storing the No. UNm of a printing unit used in the coming printing; a memory  44  for storing the ink color ICm of each printing unit UNm used in the coming printing; a memory  46  for storing a count value M; a memory  47  for storing a count value N 1 ; a memory  50  for storing a first reference value R 1   m  for switching corresponding to each ink color ICm; a memory  51  for storing the total number Nmax of the ink fountain keys of each printing unit; a memory  52  for storing a count value N 2 ; a memory  97  for storing the total value Ks of the ink fountain keys of each printing unit used in the coming printing; a memory  98  for storing the average value Kam of the ink fountain keys of the respective printing units used in the coming printing; a memory  99  for storing the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key and the opening amount Kmn 1  of the N 1 th ink fountain key of each printing unit UNm used in the coming printing; and a memory  100  for storing the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key and the opening amount Kmn 1  of the N 1 th ink fountain key of each printing unit UNm used in the coming printing.  
         [0305]     An input device  57 , such as a keyboard, various switches, and a button, a display device  58 , such as CRT and a lamp, and an output device  59 , such as an F-D drive, and a printer, are connected to the input/output device  53 . To the input/output device  54 , there are connected a valve  60 - 1  for an air cylinder for switching the roller route of the first printing unit through a valve  60 -M for an air cylinder for switching the roller route of the Mth printing unit corresponding to the air cylinder  25 - 1  for switching the roller route of the first printing unit through the air cylinder  25 -M for switching the roller route of the Mth printing unit.  
         [0306]     To the interface  55 , there are connected a printing press control device  61 , and a first ink fountain key opening amount control device  62 - 1  through a (M×N)th ink fountain key opening amount control device  62 -(M×N).  
         [0307]     The printing press control device  61  controls the entire printing press, including a feeding unit, first to Mth printing units, and a delivery unit which are not shown.  
         [0308]     As shown in  FIG. 30 , the first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) comprise the following: CPU  64 , RAM  65 , ROM  66 , and a memory  69  for storing the count value of a counter, and a memory  70  for storing a current ink fountain key opening amount are connected via a bus-line (BUS)  73  together with an input/output device  71  and an interface  72 .  
         [0309]     To the input/output device  71 , an ink fountain key drive motor  74  is connected via an ink fountain key drive motor driver  75 , and an ink fountain key drive motor rotary encoder  76  incorporated in the ink fountain key drive motor  74  is connected via a counter  77 . A detection signal from the ink fountain key drive motor rotary encoder  76  is inputted into the ink fountain key drive motor driver  75 . The aforementioned switching control device  30 A is connected to the interface  72 .  
         [0310]     Because of the above configuration, the switching control device  30 A acts in accordance with action flows shown in  FIGS. 31   a  through  31   e  and  FIG. 32 .  
         [0311]     That is, it is determined in Step P 1  whether a switching control start switch in the input/output device  57  is ON or not. If ON, each memory is initialized in Step P 2 . If not ON, it is determined in Step P 3  whether a printing completion signal has been outputted from the printing press control device  61 . If YES, outputting of a switching signal to the valves  60 - 1  through  60 -M for air cylinders for switching the roller routes of all printing units is stopped in Step P 4 , and the program returns to Step P 1 . If NO, the program immediately returns to Step P 1 .  
         [0312]     Then, in Step P 5 , the number Mmax of the printing units used in the coming printing, the printing unit No. UNm, and the ink color ICm of each printing unit UNm are inputted, and stored into the memories  42  to  44 . Then, in Step P 6 , 1 is written into the memory  46  for storing the count value M. Also, in Step P 7 , 1 is written into the memory  52  for storing the count value N 2 .  
         [0313]     Then, in Step P 8 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 9 , a command for transmitting the opening amount Kmn 2  of the ink fountain key is outputted to the N 2 th ink fountain key opening amount control devices  62 - 1  to  62 -(M×N) of the printing unit of the printing unit No. UNm. Then, if, in Step P 10 , the opening amount Kmn 2  of the ink fountain key is transmitted from the N 2 th ink fountain key opening amount control devices  62 - 1  to  62 -(M×N) of the printing unit of the printing unit No. UNm, the opening amount Kmn 2  of the ink fountain key is received from the N 2 th ink fountain key opening amount control devices  62 - 1  to  62 -(M×N) of the printing unit of the printing unit No. UNm, and stored in the memory  39 , in Step P 11 .  
         [0314]     Then, in Step P 12 , 1 is added to the count value N 2 , and the sum is written over the memory  52 . Then, in Step P 13 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 , and in Step P 14 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys for each color.  
         [0315]     If YES in Step P 14 , 1 is added to the count value M, and the sum is written over the memory  46  in Step P 15 . If NO in Step P 14 , the program returns to Step P 9 .  
         [0316]     Then, in Step P 16 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 17 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, 1 is written into the memory  46  for storing the count value M, in Step P 18 . If NO, the program returns to Step P 7 .  
         [0317]     Then, in Step P 19 , 2 is written into the memory  47  for storing the count value N 1 . Then, in Step P 20 , the No. UNm of the Mth printing unit used in the coming printing is read from the memory  43 . Then, in Step P 21 , the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 .  
         [0318]     Then, in Step P 22 , the opening amount Kmn 1  of the N 1 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 . Then, in Step P 23 , the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is computed, and stored into the memory  99 .  
         [0319]     Then, in Step P 24 , the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is computed, and stored into the memory  100 . Then, in Step P 25 , the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  44 .  
         [0320]     Then, in Step P 26 , the first reference value R 1   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  50 . Then, in Step P 27 , it is determined whether the absolute value |Km(n 1 - 1 )−Kmn 1 | of the difference between the opening amount Km(n 1 - 1 ) of the (N 1 - 1 )th ink fountain key of the Mth printing unit UNm used in the coming printing and the opening amount Kmn 1  of the N 1 th ink fountain key is equal to or larger than the first reference value R 1   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0321]     If YES in Step P 27 , 1 is written into the memory  52  for storing the count value N 2  in Step P 28 . If NO, the program shifts to Step P 42  to be described later.  
         [0322]     Then, in Step P 29 , the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is initialized. Then, in Step P 30 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is read from the memory  39 . Then, in Step P 31 , the value of the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is loaded.  
         [0323]     Then, in Step P 32 , the opening amount Kmn 2  of the N 2 th ink fountain key of the Mth printing unit UNm used in the coming printing is added to the value of the memory for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing, and the sum is written over the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing. Then, in Step P 33 , 1 is added to the count value N 2 , and the sum is written over the memory  52 .  
         [0324]     Then, in Step P 34 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 35 , it is determined whether the count value N 2  is greater than the total number Nmax of the ink fountain keys of each printing unit. If YES, the value of the memory  97  for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is loaded in Step P 36 . If NO, the program returns to Step P 30 .  
         [0325]     Then, in Step P 37 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 38 , the value of the memory for storing the total value Ks of the opening amounts of the ink fountain keys of the printing unit UNm used in the coming printing is divided by the total number Nmax of the ink fountain keys of each printing unit to obtain the average value Kam of the opening amounts of the ink fountain keys of the Mth printing unit UNm used in the coming printing, and the average value Kam is stored in the memory  98 .  
         [0326]     Then, in Step P 39 , the second reference value R 2   m  for switching corresponding to the ink color ICm of the Mth printing unit UNm used in the coming printing is read from the memory  36 . Then, in Step P 40 , it is determined whether the average value Kam of the opening amounts of the ink fountain keys of the Mth printing unit UNm used in the coming printing is equal to or greater than the second reference value R 2   m  for switching corresponding to the ink color of the Mth printing unit UNm used in the coming printing.  
         [0327]     If YES in Step P 40 , the No. UNm of the Mth printing unit used in the coming printing is written into the memory  37  for storing the printing unit No. for switching roller throw-on in Step P 41 . Then, the program shifts to Step P 45  to be described later. If NO, 1 is added to the count value N 1 , and the sum is written over the memory  47 , in Step P 42 .  
         [0328]     Then, in Step P 43 , the total number Nmax of the ink fountain keys of each printing unit is read from the memory  51 . Then, in Step P 44 , it is determined whether the count value N 1  is greater than the total number Nmax of the ink fountain keys for each color. If YES, 1 is added to the count value M, and the sum is written over the memory  46 , in Step P 45 . If NO, the program returns to Step P 21 .  
         [0329]     Then, in Step P 46 , the number Mmax of the printing units used in the coming printing is read from the memory  42 . Then, in Step P 47 , it is determined whether the count value M is greater than the number Mmax of the printing units used in the coming printing. If YES, the contents of the memory  37  for storing the printing unit No. for switching roller throw-on are written into the memory  40  for storing the printing unit No. for switching roller throw-on setting in Step P 48 . If NO, the program returns to Step P 20 .  
         [0330]     Then, the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting is loaded in Step P 49 . Then, in Step P 50 , a switching signal is outputted to the valves  60 - 1  through  60 -M for the roller route switching air cylinders of the first printing unit No. stored in the memory  40  for storing the printing unit No. for switching roller throw-on setting. Then, in Step P 51 , the first printing unit No. is deleted from the memory  40  for storing the printing unit No. for switching roller throw-on setting.  
         [0331]     Then, in Step P 52 , the contents of the memory  40  for storing the printing unit No. for switching roller throw-on setting are checked. Then, in Step P 53 , it is determined whether the stored printing unit No. is absent in the memory  40  for storing the printing unit No. for switching roller throw-on setting. If YES, the program returns to Step P 1 . If NO, the program returns to Step P 49 .  
         [0332]     The first ink fountain key opening amount control device  62 - 1  through the (M×N)th ink fountain key opening amount control device  62 -(M×N) also act in accordance with an action flow shown in  FIG. 33 .  
         [0333]     That is, if the opening amount Kmn 2  of the ink fountain key is transmitted from the switching control device  30 A in Step P 1 , the count value of the counter  77  is loaded, and stored in the memory  69  in Step P 2 . Then, in Step P 3 , the current ink fountain key opening amount is computed from the count value of the counter  77 , and stored in the memory  70 .  
         [0334]     Then, in Step P 4 , the opening amount Kmn 2  of the ink fountain key is transmitted to the switching control device  30 A. Thereafter, this procedure is repeated.  
         [0335]     In the present embodiment, as described above, the opening amount (Kmn) of each ink fountain key of each printing unit is found, and the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amounts of the adjacent ink fountain keys is found. If this difference (absolute value) is equal to or greater than a certain value (first reference value R 1   m : third reference value in the claim) in even one of the ranges (see  FIG. 5   b ), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). If there is no such range (see  FIG. 5   a ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing an ink transport route where color irregularities or the like minimally occur (i.e., second ink transport route).  
         [0336]     By so doing, the burden on the operator is lightened, and the rate of operation is increased. Furthermore, forgetting to do switching is avoided, thus eliminating a waste of printing material.  
         [0337]     If, in the present embodiment, the difference (Km(n 1 - 1 )−Kmn 1 ) between the opening amounts of the adjacent ink fountain keys is equal to or greater than the certain value (first reference value R 1   m ), the average of the opening amounts of the respective ink fountain keys is obtained. Only when the obtained average value (Kam) is equal to or greater than a certain value (second reference value R 2   m : fourth reference value in the claim), the ink distribution roller  4   e  is automatically thrown on the ink oscillating roller  5   b  to supply a larger amount of ink to the ink form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where a ghost or the like minimally occurs (i.e., first ink transport route). When the average value is smaller than the certain value (second reference value R 2   m ), on the other hand, the ink distribution roller  4   e  is automatically thrown off the ink oscillating roller  5   b  to supply a smaller amount of ink to the ink, form rollers  6   b ,  6   c  on the dampening side, thus establishing the ink transport route where the ink is minimally emulsified (i.e., second ink transport route). Furthermore, the average value (Kam) of the opening amounts of the ink fountain keys is the value obtained by dividing the total value (Ks) of the opening amounts of the ink fountain keys by the total number Nmax of the ink fountain keys of the respective printing units. Since the total number Nmax of the ink fountain keys of the respective printing units is a constant value, it goes without saying that the total value (Ks) may be obtained instead of the average value (Kam) of the opening amounts (Kmn) of the ink fountain keys, and this total value (Ks) may be compared with the certain value (second reference value R 2   m ).  
         [0338]     By so doing, the operator&#39;s judgment becomes unnecessary, the burden on the operator is lightened, the operator&#39;s mistake in switching is avoided, and the rate of operation is further increased. Also, a waste of printing material is eliminated further. In the above embodiment, moreover, the ink distribution roller  4   e  is thrown on the ink oscillating roller  5   b  when the opening amount difference (Km(n 1 - 1 )−Kmn 1 ) is equal to or greater than the first reference value and the average value (Kam) is equal to or greater than the second reference value. However, the ink distribution roller  4   e  may be thrown on the ink oscillating roller  5   b  when the opening amount difference (Km(n 1 - 1 )−Kmn 1 ) of the ink fountain key is greater than the first reference value and the average value (Kam) is greater than the second reference value.  
         [0339]     Furthermore, in the present embodiment, unlike Embodiment 3, the actual ink fountain key opening amount (Kmn) is detected by the detection signal from the ink fountain key drive motor rotary encoder  76 , without using the image area rate-ink fountain key opening amount conversion table corresponding to each ink color ICm. Thus, there is the advantage that the control device can be simplified.  
         [0340]     The invention thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.