FOLDING MACHINE IN A ROTARY PRESS

Abstract: A folding machine in a rotary press of the type that a printed paper web (W) is twice-folded and then cut into folded sheets by means of cutter drums (10,11), and the folded sheets (SA,SB) are conveyed through a distributor section (D) on the downstream side to a pair of ejected paper sheet runners (22,23) as pinched by belts (12,13), is improved in the following points. That is, conveyor means for conveying the folded sheets (SA,SB) is composed of a pair of first conveyor belts (12,13) between the outlet side of the cutter drums (10,11) and the upper stream of the distributor section (D), a pair of distributor belts (16, 17) form­ ing the distributor section (D) jointly with a triangular guide (26) disposed on the downstream side thereof, two pairs of second conveyor belts (18,20) between the down stream of the dis­ tributor section (D) and the inlet sides of the pair of ejected paper sheet runners (22,23), and guide belts (14,15) or fixed guide members between the upper stream of the distributor section (D) and the inlet side of the distributor section (D) and between the outlet side of the distributor section (D) and the lower stream of the distributor section (D). These belt pairs are formed respectively as independent closed routes. The pair of distributor belts (16, 17) are respectively provided with uneven portions along the belt length adapted to be meshed with each other and having a length equal to the length of the folded sheets (SA, SB), and flat portions having a length equal to the length of the folded sheets (SA, SB) at a pinching section for the folded sheets (SA, SB), and adapted to pinch the opposite edge portions of the folded sheets (SA, SB). Preferably, the pair of distributor belts (16, 17) are made to run at a higher speed than the pair of first conveyor belts (12, 13), and the two pairs of second conveyor belts (18, 20) are made to run at a higher speed than the pair of distributor belts (16, 17).

Description: BACKGROUND OF THE INVENTION: Field of the Invention: The present invention relates to a folding machine in a rotary press. Description of the Prior Art: One example of the known folding machine in a rotary press in the prior art is illustrated in Fig. 5(a). In this figure, successive sheets cut out from a web by means of a pair of rotating cutter drums 10 and 11 are led to a distributor section D as pinched between a pair of conveyor belts 12 and 13, and here they are distributed alternately to different directions. The cut sheets distributed to one direction are pinched between another conveyor belt 25 and the conveyor belt 12 on the downstream side of a tapered guide 23 and conveyed to a rotary runner 34 in a gathering station at the lower stream. The remainder of the cut sheets distributed to the other direction are likewise pinched between another conveyor belt 26 and the conveyor belt 13 on the downstream side of the tapered guide 23 and conveyed to a rotary runner 50 at the lower stream. In this way, the successive sheets cut out by the cutter drums 10 and 11 are distributed alternately to different directions and gathered at different gathering stations. A detailed structure of the distributor section D is shown in Figs. 6 and 7. On shafts 62 and 63 disposed in parallel to each other and simultaneously driven, are mounted guide rolls 19 and 20 for guiding conveyor belts 12 and 13, respectively, and a pair of rotary sheet diverters 60 and 61 disposed coaxially with the guide rolls 19 and 20, and these rotary sheet diverters 60 and 61 are respectively provided with protruded cam surfaces 60a and 61a and recessed portions 60b and 61b. In addition, a tapered guide 23 having a pair of diverging sheet guide surfaces 23a and 23b consisting of concave surfaces is provided between the conveyor belts 12 and 13 tracing diverging routes just downstream of the rotary sheet diverters 60 and 61. Since the rotary guide rolls 19 (20) and the rotary sheet diverters 60 (61) are disposed alternately on the shaft 62 (63), the belt 12 (13) guided by the rotary guide rolls 19 (20) and the cam surfaces 60a (61a) provided on the rotary sheet diverters 60 (61) are adapted to be interlaced with each other in the widthwise direction of the sheet. Distribution of the sheets is carried out in the following manner. When the cut sheets SA and SB (See Fig. 5(b)) are alternately and continuously fed to between the rotary sheet diverters 60 and 61 by the conveyor belts 12 and 13, the initial sheet SA is diverted into the flow path formed between the sheet guide surface 23a and the conveyor belt 12 by the protruded cam surface 61a of the rotary sheet diverter 61, subsequently the sheet SA is delivered into a sheet receiving gap formed by the conveyor belts 12 and 25, and thereafter it is sent to the rotary runner 34 existing on the downstream side as pinched by the belts 12 and 25. In succession, the next cut sheet SB is sent to between the rotary sheet diverters 60 and 61, but at this time the protruded cam surface 61a has been rotated to a position outside of the route for the sheet SB and instead the protruded cam surface 60a of the rotary sheet diverter 60 has entered the route for the sheet SB, hence the sheet SB is diverted into the flow path formed between the sheet guide surface 23b and the conveyor belt 13, and it is sent to the rotary runner 50 that is different from that for the sheet SA by the conveyor belts 13 and 26. Still further, when the sheet SA subsequent to the last-mentioned sheet SB has been sent to the rotary sheet diverter D, the protruded cam surface 60a has been rotated to a position outside of the route for the sheet SA, hence the cam surface 61a again returns into the traveling route for the sheet SA, and the above-described sequence of operations is repeated. In addition, after the conveyor belts 12 and 13 have been formed into converging routes by means of a pair of rolls 14 and 15 for the purpose of receiving the successive sheets, they are further formed into parallel routes close to each other by means of rolls 17 and 18, and then they are led into the distributor section D. Subsequently, the conveyor belt 12 is formed into one route of divergent routes by means of the rotary guide rolls 19 and 20 combined with the distributor section D, and on the downstream side of the tapered guide 23 it forms a closed route jointly with another belt 25 and cooperates therewith to send the distributed sheets to the collecting station. Likewise, after passing through the rotary guide rolls 19 and 20, the conveyor belt 13 cooperates with another belt 26 to send the distributed sheets to the collecting station. In this way, the conveyor belts 12 and 13 form a continuous closed route extending from the position for receiving the cut sheets through the distributor section D up to the sheet collecting station, further passing through returning guide rolls and returning to the position for receiving the cut sheets. However, the cam surfaces in the distributor section in the prior art merely perform distribution of sheets in the diverging space formed by a pair of conveyor belts, they do not have a capability of conveying a sheet as positively holding it, accordingly upon passing through the distributor section, a thin paper sheet or a sheet having a small area was liable to produce waving, scratching, creasing and paper blocking, and so, a stability was poor. Also, since the cam plates and the conveyor belts are disposed in a meshed condition in the widthwise direction of the sheets, it was impossible that both the cam plate surface and the conveyor surface support the sheet edge portions which present the most unstable behavior among the entire width of the sheets, and accordingly, there was a risk that the edge of the sheet may be folded either in the distributor section on in the route of the conveyor belts. Furthermore, since each of the pair of conveyor belts is formed of a single belt continuing over the route extending from the position for receiving the cut sheets through the distributor section up to the sheet collecting station, the belts are compelled to run at a predetermined equal speed through the entire route, consequently a waving condition of a sheet generated in the direction of the sheet flow in the space within the diverging belt route before and behind the distributor section would be led to the downstream conveyor belts without being eliminated, and there was a risk that creases may be introduced to the sheet in the direction perpendicular to the flow direction. Document GB-A-13 11 483 discloses diverting means used in folders for printing presses, wherein two rotating disk shaped cam plates of a diverter alternatingly divert and guide folded sheets supplied by a main conveyor to two branch conveyors. SUMMARY OF THE INVENTION: It is therefore one object of the present invention to provide an improved folding machine in a rotary press, in which successive printed and cut sheets can stably pass through a distributor section without producing waving, scratching, creasing and paper blocking. Another object of the present invention is to provide a folding machine in a rotary press, in which conveyor belts for conveying successive printed and cut sheets through a distributor section can run at different speeds in the respective sections of a conveying route, and thereby the risk of generating creases in the direction perpendicular to the flow direction of the sheets can be eliminated. According to one feature of the present invention there is provided a folding machine in a rotary press of the type that a printed paper web is twice-folded and then cut into folded sheets by means of cutter drums, and the folded sheets are conveyed through a distributor section on the downstream side to a pair of ejected paper sheet runners as pinched by belts, improved in that conveyor means for conveying the folded sheets is composed of a pair of first conveyor belts between the outlet side of the cutter drums and the upper stream of the distributor section, a pair of distributor belts forming the distributor section jointly with a triangular guide disposed on the downstream side thereof, two pairs of second conveyor belts between the down stream of the distributor section and the inlet sides of the pair of ejected paper sheet runners, and guide belts or fixed guide members between the upper stream of the distributor section and the inlet side of the distributor section and between the outlet side of the distributor section and the lower stream of the distributor section, these belt pairs are formed respectively as independent closed routes, and the pair of distributor belts are respectively provided with uneven portions along the belt length adapted to be meshed with each other and having a length equal to the length of the folded sheets, and flat portions having a length equal to the length of the folded sheets at a pinching section for the folded sheets, and adapted to pinch the opposite edge portions of the folded sheets. According to another feature of the present invention, there is provided the above-featured folding machine in a rotary press, further improved in that the pair of distributor belts are made to run at a higher speed than the pair of first conveyor belts, and the two pairs of second conveyor belts are made to run at a higher speed than the pair of distributor belts. According to the present invention having the above-described structural feature, the folded sheets fed from the cutter drums are at first conveyed to the upper stream of the distributor section by the first conveyor belts, and they enter the distributor section as guided by either the guide belts or the fixed guide members. The folded sheets having entered the distributor section are distributed to predetermined directions under the condition of being firmly pinched between the mutually meshing uneven portions of the distributor belts having a length equal to the length of the folded sheet, and then they enter the second conveyor belts as guided by the guide belts or the fixed guide members and would be conveyed to the ejected paper sheet runners. In addition, by making the first conveyor belts, the distributor belts and the second conveyor belts run at successively increased speeds, the waving condition of the folded sheet can be eliminated and creasing can be prevented. According to the present invention, owing to the above-described structural features and inherent operations, a waving condition of the sheet generated in the flow direction of the sheet can be eliminated, the sheet can be more sufficiently and even in the case of thin paper sheets or small-sized sheets, the fear of producing waving scratching, creasing and paper blocking can be obviated, and further, the fear of the sheet edge being folded would be eliminated. The above-mentioned and other objects, features and advantages of the present invention will become more apparent by reference to the following description of one preferred embodiment of the invention taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS: In the accompanying drawings: Fig. 1(a) is a general structural view of a folding machine in a rotary press according to one preferred embodiment of the present invention; Fig. 1(b) is a schematic view showing a series of cut folded sheets; Fig. 2 is an enlarged front view of a distributor section D in Fig. 1(a); Fig. 3 is a side view of the distributor section D in Fig. 2; Fig. 4 is a structural view of a triangular guide; Fig. 5(a) is a general structural view of a folding machine in a rotary press in the prior art; Fig. 5(b) is a schematic view showing a series of cut folded sheets; Fig. 6 is an enlarged front view of a distributor section D in Fig. 5(a); and Fig. 7 is a side view of the distributor section D in Fig. 6. DESCRIPTION OF THE PREFERRED EMBODIMENT: In the following, the present invention will be described with reference to Figs. 1 to 4 of the accompanying drawings. As will be seen from these figures, a web W twice-folded by means of a triangular plate (not shown) is cut into a preset length by cutter drums 10 and 11 after it has entered between a pair of first conveyor belts 12 and 13, and becomes folded sheets (hereinafter called simply "sheets") SA and SB, and thereafter as soon as the folded sheet is released from the first conveyor belts 12 and 13 at rolls 30a and 36a, it is sent to a distributor section D as guided by a pair of guide belts 14 and 15, which are led by rolls 30b and 36b provided on the same shafts as the rolls 30a and 36a, respectively. The sheets SA and SB sent to the distributor section D are distributed alternately to the left and to the right with respect to a central running position (that is, the position on the straight line passing a central point between the axes of rolls 40 and 43 and a central point between the axes of rolls 41 and 44). At the just lower stream of the distributor section D, a pair of guide belts 14 and 15 are guided in a diverging manner by rolls 47b and 59b, and within the diverging routes of the guide belts is disposed a triangular guide 26 with one apex of the triangle placed on the above-mentioned central running positions and directed to the upstream side. The sheet SA distributed to one direction at the distributor section D passes through the path between one guide surface 26a and the guide belt 14 and is sent to between a pair of second conveyor belts 18 and 20 on one hand at the lower stream, while the succeeding sheet SB is distributed to the other direction, than passes through the path between the other guide surface 26b and the guide belt 15 and is sent to between a pair of second conveyor belts 19 and 21 on the other hand at the lower stream. In this way, the sheets SA and SB which have been guided through the same route up to the first conveyor belts are alternately distributed to different routes, that is, to the route of one pair of second conveyor belts 18 and 20 and to the route of the other pair of second conveyor belts 19 and 21, the sheet SA is discharged via an ejected paper sheet runner 22 onto an ejected paper sheet conveyor 24 and then sent to one collecting station, and likewise the sheet SB is discharged via an ejected paper sheet runner 23 onto an ejected paper sheet conveyor 25 and then sent to another collecting station. Now, the distributor section D consists of a pair of distributor belts 16 and 17, and rolls 40, 41a and 42a and rolls 43, 44a and 45a for respectively guiding these distributor belts to run, and on the same shafts as the rolls 41a and 42a and the rolls 44a and 45a are respectively provided rolls 41b and 42b and rolls 44b and 45b for guiding a pair of guide belts 14 and 15, respectively. The running path of the distributor belt 16 between the rolls 40 and 41a and the running path of the distributor belt 17 between the rolls 43 and 44a are held in parallel to each other, and thus form a parallel running section of the sheets SA and SB. The pair of distributor belts 16 and 17, respectively, have uneven portions consisting of thick parts 16a and 17a and thin parts 16b and 17b along the belt length, and they revolve synchronously so that the thick part 16a and the thin part 17b, and the thin part 16b and the thick part 17a may mesh with each other with the sheets SB and SA, respectively, pinched therebetween in the above-mentioned parallel running section. As a matter of course, these uneven portions of the distributor belts 16 and 17 have a sufficient length for pinching the sheet SA or SB over its entire length. When the sheets SA and SB have been fed to the distributor section D constructed as described above, at first the sheet SA is pinched between the thin part 16b and the thick part 17a of the distributor belts 16 and 17, respectively, and is sent to the lower stream under the condition of being shifted from the above-mentioned central running position towards the distributor belt 16, and therefore, it advances into the gap between one guide surface 26a (on the side of the distributor belt 16) of the triangular guide 26 having its upstream side apex placed at the above-mentioned central running position, and one guide belt 14 guided in a diverging manner. The next succeeding sheet SB is now pinched between the thick part 16a and the thin part 17b of the distributor belts 16 and 17, respectively, and is sent to the lower stream under the condition of being shifted from the above-mentioned central running position towards the distributor belt 17, and therefore, it advances into the gap between the other guide surface 26b (on the side of the distributor belt 17) of the triangular guide 26 and the other guide belt 15. In this way, for the sheets being fed continuously to the distributor section D, the alternate distributing operations as described above in connection to the sheets SA and SB are repeated. In addition, as shown in Fig. 3, the distributor belt 16 (17) in the distributor section D is disposed so as to pinch the opposite edge portions of a sheet like the first conveyor belt 12 (13) at the upper stream and the second conveyor belts 18 and 20 (19 and 21) at the lower stream, and thereby unstable behaviors of the opposite edge portions of a sheet during high speed conveyance can be prevented. Furthermore, since the pair of first conveyor belts 12 and 13, the pair of distributor belts 16 and 17, and the two pairs of second conveyor belts 18 and 20, and 19 and 21 are guided so as to run respectively through independent closed routes, and adapted to be driven respectively by independent drive rolls, the first conveyor belts 12 and 13 can be made to run at several percent to ten and several percent higher speed than the running speed of the web W before cutting for the purpose of broadening a sheet interval after cutting to several tens millimeters, the pair of distributor belts 16 and 17 can be made to run at several tenths percent to several percent higher speed than the running speed of the first conveyor belts 12 and 13, and the second conveyor belt pairs 18 and 20, and 19 and 21 can be made to run at several tenths percent to several percent higher speed than the running speed of the distributor belts 16 and 17, it is possible to eliminate a waving condition of the sheets and to prevent creasing of the sheets. In addition, if the triangular guide 26 is designed to be a triangular guide provided with nozzle holes 26c, 26d and 26e and nozzle holes 26f, 26g and 26h, respectively, on the guide surfaces 26a and 26b as shown in Fig. 4 according to necessity, then by blowing out pressurized air from these holes, the sheets can be made to pass without coming into contact with the guide surfaces 26a and 26b, and also by blowing out charged air, state electricity on the sheets can be removed. In order that the gap distance of the sheet pinching portions of the first conveyor belts 12 and 13, the distributor belts 16 and 17, the second conveyor belts 18 and 20, and 19 and 21, and the guide belts 14 and 15 are made variable depending upon the thickness and the property of the sheets, the structure is such that the roll groups for guiding these belts are respectively mounted to separate frames (not shown), and the whole frames can be moved to the left or to the right. It is to be noted that while the guide belts 14 and 15 running nearly at the same speed as the distributor belts 16 and 17 are employed in the illustrated embodiment, in the case where the stiffness of the paper sheet to be handled is not small, in place of the guide belts 14 and 15, fixed paper sheet guides could be disposed between the first conveyor belts 12 and 13 and the distributor belts 16 and 17, and along the guide surfaces 26a and 26b of the triangular guide 26 between the distributor belts 16 and 17 and the respective second conveyor belts 18 and 20, and 19 and 21, respectively. As described in detail above, in the folding machine in a rotary press according to the present invention, since the conveyor means for the sheets extending from the cutter drums to the ejected paper sheet runners is composed of first conveyor belts, distributor belts, the second conveyor belts and guide belts (or fixed guide members), a waving condition of the sheet generated in the flow direction of the sheet can be eliminated by selecting the conveying speed on the downstream side a little faster than that on the upstream side, also by forming a flat portion having a length equal to the sheet length at the sheet pinching portion by means of the distributor belts, the sheet can be sufficiently pinched by the distributor belts, hence even in the case of thin paper sheets or small-sized sheets the fear of waving, scratching, creasing and paper blocking can be eliminated, and further, since the opposite edge portions of the sheet which present the most unstable behavior during conveyance are pinched except for the guide belts, the fear of the sheet edge portions being folded would disappear.

Claims: A folding machine in a rotary press, in which a printed paper web (W) is twice-folded and then cut into folded sheets by means of cutter drums (10, 11), and said folded sheets (SA, SB) are conveyed through a distributor section (D) on the downstream side to a pair of ejected paper sheet runners (22, 23) as pinched by belts (12, 13; 16, 17); characterized in that conveyor means for conveying said folded sheets (SA, SB) is composed of a pair of first conveyor belts (12, 13) between the outlet side of said cutter drums (10, 11) and the upper stream of said distributor section (D), a pair of distributor belts (16, 17) forming said distributor section (D) jointly with a triangular guide (26) disposed on the downstream side thereof, two pairs of second conveyor belts (18, 20; 19, 21) between the down stream of said distributor section (D) and the inlet side of said pair of ejected paper sheet runners (22, 23), and guide belts (14, 15) or fixed guide members between the outlet of the upper stream and the inlet of the lower stream, these belt pairs are formed respectively as independent closed routes, and said pair of distributor belts (16, 17) are respectively provided with uneven portions (16a, 17a, 16b, 17b) along the belt length adapted to be meshed with each other and having a length equal to the length of said folded sheets (SA, SB), and flat portions having a length equal to the length of said folded sheets (SA, SB) at a pinching section of said folded sheets (SA, SB), and adapted to pinch the opposite edge portions of said folded sheets (SA, SB). A folding machine in a rotary press as claimed in Claim 1, wherein the pair of distributor belts (16, 17) are made to run at a higher speed than the pair of first conveyor belts (12, 13), and the two pairs of second conveyor belts (18, 20; 19, 21) are made to run at a higher speed than the pair of distributor belts (16, 17).

Inventors: MORITA, YASUO C/O MIHARA MACHINERY WORKS, NOMI, KAZUTOSHI C/O MIHARA MACHINERY WORKS, SATO, MANABU C/O MIHARA MACHINERY WORKS, SHOJI, YUKIKAZU C/O MIHARA MACHINERY WORKS
Applicants: MITSUBISHI JUKOGYO KABUSHIKI KAISHA
Application year: 1988
Main classification: B41F13
IPC codes: B65H29, B41F13, B65H5