Abstract:
A newspaper producing method can produce a plurality kinds of newspapers different in page numbers and colors by using a single printing unit. This method includes a plurality of printing cycles, each of which produces a plurality of lateral printed rows on each side of a continuous web, with each row having different contents relative to each other, with each row having at least two printed segments in a width direction of the continuous web, and with rows on opposite sides of the continuous web corresponding to each other. This printed continuous web is cut with respect to each of the lateral printed rows and each two-page spread of newspaper, and these cut portions are set and are delivered for every printing cycle. Each set of these portions is folded at a longitudinal central portion of a two-page spread thereof.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method of producing newspaper having a number of pages such as sixteen pages, thirty-two pages, forty pages, etc. 
     2. Related Art 
     In a known art, newspaper is produced by steps of printing a continuous web of paper in a form of a double-width size web sheet (laterally corresponding to four pages of newspaper) by using a rotary press, slitting this printed continuous web in its longitudinal direction into two portions (each laterally corresponding to two pages of newspaper) by using a slitter, overlapping the two portions and then folding them in their longitudinal direction by using a former, cutting this folded paper web in its transverse direction so as to have a predetermined vertical length of the newspaper and then delivering the same. 
     FIG. 4 shows a process explaining the above newspaper producing steps by using a blanket-blanket type offset rotary press. With reference to FIG. 4, the offset rotary press includes two opposed plate cylinders a, each of which is mounted with a printing plate having two lateral printing rows juxtaposed in a circumferential direction, and each of which having four printing surfaces adapted to print four pages of A, B, C and D or E, F, G and H of the newspaper in an axial direction of the plate cylinders. According to complete rotations of two opposed blanket cylinders b, a continuous web of paper c (which will be called hereinlater “continuous web” or merely “web”) is printed by eight pages on respective surfaces of both sides of the continuous web. In such case, the continuous web c has a width twice a lateral width of a newspaper having four pages when the latter is opened, i.e. 1625 mm (64 inches). 
     Thereafter, by using a slitter, the continuous web c is slit into two portions in a longitudinal direction at an intermediate portion in a width direction of the web, and the two portions are overlapped at a gathering (collecting) section using a turn bar e. Thereafter, these overlapped portions are folded in folio in the longitudinal direction by using a former f, and then, this folded web is cut with respect to each row to thereby produce two kinds of newspapers each including eight pages, alternately in order. 
     At a time when the newspaper is produced by using a printing unit of a plate cylinder structure mentioned above, supposing that one printing unit has an ability for printing, for example, two kinds of eight pages, such as mentioned above, when a newspaper of sixteen, thirty-two and forty pages is printed, it is necessary to use a two-unit type, three-unit type or four-unit type rotary press having these two kinds of 8-page printing units, of which the number is increased to two (2), three (3) or 4 (four). 
     FIG. 5 shows a 4-unit type rotary press including four printing units g 1 , g 2 , g 3  and g 4 . Each of continuous webs c printed respectively at the printing units g 1  to g 4  is divided into two parts by a slitter h, and then they are gathered by using a turn bar group of a collection unit i. Thereafter, the continuous webs c are folded in folio by former f and then again folded by a folding apparatus j. 
     As mentioned hereinbefore, when a newspaper is produced by using a conventional plate-cylinder type printing unit, it is necessary to increase a number of printing units every time a number of pages of the newspaper is increased, thus being disadvantageous in production cost and installation space. Particularly, the four-unit type rotary press such as shown in FIG. 5 is considerably large in size, and hence, it requires large installation space and is, moreover, expensive. 
     Furthermore, with such a conventional printing unit, it is difficult to increase pages of a newspaper after a first setting thereof because of limitations with regard to installation space. Moreover, in multi-color printing, since a number of printing units are required, and hence a traveling path for a continuous web is extremely elongated, there results losses in paper and time only in a paper threading process, and furthermore, much paper (web) loss results until a tension is stabilized and a different color registration is made. In addition, it is required to change a printing plate every time contents to be printed are changed, which will not be profitable in production of a small number of lots. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art mentioned above, and to provide a newspaper producing method capable of producing a plurality kinds of newspapers including page numbers and colors different from each other, by utilizing a single printing unit, wherein the method is profitable for printing a small number of lots. 
     This and other objects can be achieved according to the present invention by providing a method of producing newspaper, comprising: 
     printing on both sides of a continuous web repeatedly in a printing direction, which printing includes a plurality of printing cycles each producing a plurality of lateral printed rows on each side of the continuous web, with each row having different contents relative to each other, with each row having at least two printed segments in a width direction of the continuous web, and with rows on opposite sides of the continuous web corresponding to each other; 
     cutting this printed continuous web with respect to each of the lateral printed rows and each two-page spread of newspaper, and setting and delivering a set of these cut portions at every printing cycle; and 
     folding each set of the cut portions at a longitudinally central portion of a two-page spread thereof; 
     whereby a newspaper of pages corresponding to the printing cycle is repeatedly produced. 
     In a preferred embodiment of this newspaper producing method, both sides of the continuous web are printed at a portion thereof traveling in a vertical direction. This printing is performed by using a digital printing machine including printing heads opposed to both sides of the continuous web, respectively, wherein each printing head is arranged opposite to another printing head at the same level in vertical direction. The printing may also be performed by using a digital printing machine including printing heads opposed to both sides of the continuous web, respectively, wherein the printing heads are offset relative to one another in a printing direction. 
     According to the present invention including the features mentioned above, both sides of a continuous web are printed repeatedly, by using a digital printing machine, in a printing direction such that this printing step includes a plurality of printing cycles each of which produces a plurality of lateral printed rows on each side of the continuous web, with each row having different contents relative to each other, with each row having at least two printed segments in a width direction of the continuous web, and with rows on opposite sides of the continuous web corresponding to each other. Therefore, a number of printed rows in a printing direction produced during a printing cycle mentioned above can be changed, and hence, it becomes possible to optionally produce newspapers different in pages and/or colors by using one set of a web feeding section and printing section. Thus, it is not necessary to increase a number of printing units, as with the conventional printing method using a rotary press, in conformity with pages and/or colors, and hence, according to the present invention, a newspaper can be produced at a reduced production cost and reduced printing system installation space. 
     Moreover, use of a digital printing machine makes it possible to easily change contents to be printed without changing a printing plate or the like, as with the conventional rotary press, and accordingly, only one lot printing can be performed with commercial profit. 
     Furthermore, since multi-color printing can be performed by using a digital printing machine which is compact, allowed for is a printing system that has a reduced web traveling path, and which can be operated with stable tension and reduced paper (web) loss during a web feeding process or different color registration process. 
     Further, the above and other objects, many other characteristic features and advantageous effects and the like of the present invention will be made more clear from the following descriptions made with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings: 
     FIG. 1 is an illustration for explanation of an embodiment according to the present invention; 
     FIG. 2 is a schematic view showing a setting and delivering section, and a chopper folding section, of a printing system for explaining the embodiment of the present invention; 
     FIG. 3 is a view along arrow X in FIG. 2; 
     FIG. 4 is a schematic view of a printing system of conventional structure; and 
     FIG. 5 is a front view of a conventional rotary press. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     One embodiment of the present invention will be described hereunder with reference to a case of producing newspaper of thirty-two pages which is foldable in folio. 
     With reference to FIG. 1, reference numeral  1  denotes a continuous web for double-width type newspaper. The continuous web  1  is subjected to double-side surface (perfect) printing by a double-side printing machine  2  disposed at a printing section, and the web  1  is dried by passing through a drier  3  and then split into two parts in a longitudinal direction thereof by a splitter  4 . Thereafter, the two parts are overlapped at a gathering section  5  by using a turn bar (not shown) then cut by a cutter  6  so as to have a predetermined length (vertical dimension of the newspaper) and, thereafter, stacked on a conveyor  7  for making sets of newspapers each composed of a predetermined number of papers. These newspaper sets on the conveyor  7  are delivered and discharged in a shifted state for every newspaper set. 
     The double-side printing machine  2  is arranged at a position at which the continuous web  1  is traveling in a substantially vertical direction. This double-side printing machine  2  employs a digital printer such as an ink-jet printer or electro-photography printer which can change, at random, contents on each page of the newspaper to be printed by using an on-demand controller without using printing plates. 
     The double-side printing machine  2  has printing heads  2   a  and  2   b , one of which is disposed opposed to one of both (two) sides of the continuous web  1 . However, in a case of large volume of printing contents or multi-color printing, two to four printing heads may be additionally arranged along a printing direction (traveling direction of the continuous web  1 ) as occasion demands. 
     Further, it is not absolutely necessary for the printing heads  2   a  and  2   b  disposed on respective sides in an opposing manner to be arranged at the same positions along the printing direction, and the printing heads  2   a  and  2   b  may be arranged in an offset manner in the printing direction so long as a printing timing of both printing heads can be controlled so that both printed surfaces of both sides of the newspaper correspond to each other. 
     At a double-side printing section by using the double-side printing machine  2 , one side of the continuous web  1  is provided with printed segments being arranged in four lateral rows juxtaposed in the printing direction, with each row including four printed segments corresponding to pages A-D, E-H, I-L or M-P, and this four-row printing is repeatedly performed. On the other hand, the other side of the continuous web  1  is also printed in a manner substantially identical to that mentioned above. That is, four lateral rows, each including four printed segments corresponding to those of the above-mentioned one side, are printed in the printing direction, and this lateral four-row printing is repeatedly performed, and a pair of four-row printings on both sides of the continuous web  1  are performed as one printing cycle for the newspaper, and this cycle is repeated so as to print a required number of newspaper sets. 
     With reference to FIG. 1, the continuous web  1  of double-width size (including four lateral pages of newspaper), after images have been printed on both its sides, is then dried by the drier  3 . The continuous web  1  of double-width size is slit into two parts by virtue of slitter  4  so as to provide two continuous webs each having a two-page spread width of the newspaper, which webs are then superimposed as a two-ply web at gathering section  5 . Thereafter, the superimposed webs are cut by the cutter  6  so as to provide a two-page spread of newspaper each having a stacked vertical dimension as the newspaper, which are then stacked on the setting and delivering conveyor  7 . 
     This setting and delivering conveyor  7  is operated intermittently. That is, at a time when the continuous web  1  (sheets of newspaper pages) cut by the cutter  6  are stacked on the conveyor by eight sheets, i.e. thirty-two pages, which corresponds to a printed amount in one printing cycle mentioned above, the conveyor is slightly moved so that the stacked newspaper sheets are slightly moved. This process is repeated and, then, sets of the newspapers, each including thirty-two pages, are piled and moved, having a slightly shifted state relative to each other, in a delivering direction. The newspapers on the conveyor are delivered in this state by a predetermined stroke or to a terminal end of the conveyor  7 , and then removed one by one each as one set of newspaper. 
     In the described embodiment, for example, if it is required to produce a newspaper of sixteen pages, the number of lateral rows to be printed by one printing cycle is set to two (two lateral rows), and on the other hand, in a case of a newspaper of forty pages, the number of lateral rows to be printed by one printing cycle is set to five (five horizontal rows). In these states, printing is performed repeatedly in both cases. 
     Moreover, in the described embodiment, although there is described an example using the double-width continuous web  1 , a single-width continuous web may also be used. Accordingly, in a case of a single-width web, the number of printed segments in each lateral row in the double-side printing machine  2  is half (½) of a double-width web, so that the number of lateral rows to be printed in one printing cycle becomes twice that the case of the double-width web. 
     FIG. 2 shows an arrangement of another example of a setting and delivering process. With reference to FIG. 2, cut portions  1   a  cut by cutter  6  are delivered intermittently one by one on an intermittently operated impeller device  9  via a delivering belt conveyor  8  at a delivering speed V 2 , which is slightly (about 5%) greater than an operating speed V 1  of the printing machine itself. The cut webs  1   a  abut a blade or vane, in an upright attitude, of an upstream side impeller  9   a  and are then stacked on other blades, in a horizontal attitude, opposing each other, of a downstream side impeller  9   b  and the upstream side impeller  9   a . Further, in FIG. 2, reference numeral  10  denotes a striker and  11  denotes a guide belt. 
     In this example of FIG. 2, the cut portions  1   a  stacked on the impeller device  9  are counted by a sensor  12  provided for the delivering belt conveyor  8 , and for example, when four sets of two-ply cut portions  1   a  for a preset number of pages (sheets) of for example a 32-page newspaper pass the sensor  12 , a servo-motor  13  instantaneously drives the impeller device  9  to thereby rotate both the impellers  9   a  and  9   b  by 90 degrees so as to move opposing blades in a horizontal attitude downwardly. Accordingly, the newspapers drop onto an intermittently driven conveyor  14  for every one set. 
     The conveyor  14  is intermittently driven by a servo-motor  15 , and according to this intermittent motion, a set  1   b  dropped onto the conveyor  14  is delivered to a chopper folding device  16  disposed on a downstream side of the conveyor  14 . Then, at this position, the set  1   b  is folded in folio, by a chopper blade  17  moving downwardly, at just an intermediate position in a width direction thereof, and discharged onto a delivery conveyor  20  along a guide  19  by virtue of chopper roller  18 . 
     The conveyor  14  comprises a plurality of timing belts  14   a  which are horizontally arranged spaced from each other, and pressing plates  14   b  for feeding the set  1   b  under a pressed state are provided for surfaces of the timing belts  14   a . The chopper folding device  16  is provided with a bottom board or plate  21  for supporting the set  1   b.    
     Further, in the described embodiment, as a device for setting and delivering the cut portions  1   a , cut by the cutter  6 , onto the conveyor  14 , as shown in FIG. 2, there is utilized an intermittently driven impeller device comprising a pair of impellers which intermittently rotate. However, this device may be a known continuous rotary-type impeller device, having a number of blades in its circumferential direction, wherein cut portions are subsequently inserted into a portion between blades of the continuous rotary-type impeller device and then the cut portions abut a baffle plate according to rotation of the impeller device and drop onto the conveyor  14 . 
     It is further noted that, although the present invention is disclosed with reference to the preferred embodiment of a newspaper producing method, the present invention is not limited to such a specific embodiment, and many other applications will be suggested for those skilled in the art. Furthermore, there will be cause for experts in this art field to make various amendments, modifications and changes in details of the illustrated and described embodiment so as to conform with design or the like, or with necessity of applications.