JP4416118B2 - Theta for printing press - Google Patents

Description

  The present invention relates to a sheeter for a printing press that uses air flow to guide the travel of a web or cut sheet. More specifically, the present invention relates to the rotation of a cutter cylinder by installing an air guide downstream of the cutter cylinder. The present invention relates to a sheeter for a printing press that suppresses the jumping or fluttering of the web or cut paper leading edge, prevents paper damage or paper jamming, and enables smooth high-speed running.

  A theta for a printing press includes an infeed portion having a plurality of draw rollers for taking in a web supplied at high speed from the printing press, a cutting portion for cutting the web into sheets of a predetermined size with a cutter cylinder, and the cut High-speed conveying means provided on the downstream side of the unit, low-speed conveying means for conveying the cut sheets in a tiled state, and a stack unit for stacking the conveyed cut sheets. Such a printer theta is usually installed on the downstream side of the offset rotary printing press, but may be installed offline.

  Here, the high-speed conveyance means bridges between the cut portion and the low-speed conveyance means, and has a function of conveying the web or the cut sheet at high speed in a tension state. For example, a lower air blow located on the downstream side of the cutter cylinder, an upper first vacuum drum facing the lower air blow, and an upper second vacuum drum located on the lower side facing the low speed conveying means and located on the upper side. A peeling projection arranged on the outer periphery of the second vacuum drum in parallel with the rotary shaft pushes down the rear end of the cut sheet that travels at a high speed so that the cut sheet is transferred from the high-speed conveyance means to the low-speed conveyance means and is stacked To. Such a printing machine sheeter is described in, for example, Japanese Patent Application Laid-Open No. H10-228707.

  The web or cut paper that has passed through the cutter cylinder rides on the air layer formed by the lower air blow, and is fed to the upper second vacuum drum while being sucked by the upper first vacuum drum. The cutter cylinder operates at about 500 rpm in synchronization with the rotary printing press. However, in recent years, with the further increase in the speed of the offset rotary printing press, operation at a speed of 600 to 800 rpm or more is increasing. Further, thin paper is often used for printing webs from the viewpoint of economy and the like.

  By the way, it is necessary to leave a certain distance between the cutter cylinder and the upper first vacuum drum and between the upper first vacuum drum and the upper second vacuum drum because of the mechanism for running the cut sheet. However, when the thin paper is conveyed at a high speed, the leading end of the traveling web springs up in association with the rotation of the cutter cylinder and collides with the upper first vacuum drum at an angle, which may damage the leading end of the traveling web. Alternatively, the leading end of the traveling web may greatly fluctuate and cannot pass through the upper first vacuum drum, causing a paper jam. Such trouble is likely to occur particularly when a thin and weak paper is conveyed at high speed. A paper jam can occur not only on the inlet side of the upper first vacuum drum, but also on the inlet side of the upper second vacuum drum, depending on the paper quality, paper thickness, operating conditions, and the like.

When a paper jam occurs, the operation must be stopped immediately and the jammed paper must be removed. In high-speed operation, the amount of waste paper is significant, and there is a possibility of causing great damage to the theta component. Above all, work efficiency is significantly reduced. In the future, where the trend toward thinner paper and higher speed will further increase, these are major technical issues that cannot be avoided in order to achieve long-term continuous high-speed operation.
JP 2004-26340 A

  The problem to be solved by the present invention is that, in the prior art, particularly in an operation situation in which a thin and weak cut sheet is conveyed at high speed, damage due to the jumping of the leading end of the running web on the downstream side of the cut portion with the rotation of the cutter cylinder Or, a paper jam is likely to occur.

The present invention provides an infeed portion for taking in a web, a cut portion for cutting the web into sheets of a predetermined size by a cutter cylinder, a high-speed conveying means positioned on the downstream side of the cut portion, and stacking the cut paper sheets. A low-speed conveying means for conveying the sheet in a state, and a stack portion for stacking cut sheets. The high-speed conveying means is opposed to a lower air blow having a plurality of air outlets on the upper surface for forming an air flow in the web running direction. An upper first vacuum drum and an upper second vacuum drum positioned on the upper side facing the low-speed conveying means on the downstream side of the upper first vacuum drum are transported while pulling the front end of the web by the air flow by the lower air blow. The trailing edge of the cut sheet is pushed down by the separation protrusions arranged on the outer periphery, so that the cut sheet is transferred from the high-speed conveying means to the low-speed conveying means to be in a tiled state. In theta printing machine, above the traveling web or cut sheet between the first vacuum drum and on the cutter cylinder, located a box-like air guide extending in the sheet width direction, the air guide is lower bottom toward the downstream side It is provided as (forwardly downward) inclined to, and the bottom surface of the air guide with a large number of the nozzle holes for blowing out flat the error a to the running direction of the web or cut sheet is dispersed form, of the air guide and guide plates extending to opposed the vicinity of the lower air blow of the upper first vacuum drum is provided from the downstream end of the bottom surface, each of the web leading end to be Haneagaro with the rotation of the cutter cylinder air guide guided to the downstream side while suppressing an air flow blown out from the nozzle holes, the air web or cut sheet is due to the air layer and the air guide according to the lower air blow travels A theta printing machine is characterized in that so as to be sandwiched guided onto the first vacuum drum at. Here, the inclination angle of the bottom surface of the air guide is preferably set to about 10 to 20 degrees.

  In addition, a box-shaped second air guide extending in the paper width direction is slightly above the running web or cut paper between the upper first vacuum drum and the upper second vacuum drum and is slightly parallel to the surface of the web or cut paper. It is preferable to install through a gap. A number of nozzle holes for blowing air in a flat manner are also distributed and formed on the bottom surface of the second air guide.

  In the sheeter for a printing press according to the present invention, an air guide is installed between the cutter cylinder and the upper first vacuum drum in a forward and downward direction toward the traveling direction of the web or cut paper. The cut paper runs between the air layer formed by the lower air blow and the air layer formed by the air guide. Therefore, the web tip is not damaged and paper jams can be prevented regardless of the paper quality, paper thickness, and operating conditions.

  In addition, if the second air guide is installed between the upper first vacuum drum and the upper second vacuum drum, the cut paper travels in a more stable state, and paper jams near the upper second vacuum drum are ensured. Can be prevented. As a result, it is possible to almost completely eliminate the occurrence of waste paper in the high-speed conveying means, and it is not necessary to dispose of the waste paper. Therefore, the work efficiency is improved, and high-speed continuous operation can be easily performed for a long time.

  The sheeter for a printing press includes an infeed portion having a plurality of draw rollers for taking in the web, a cut portion for cutting the web into sheets of a predetermined size with a cutter cylinder, and a high-speed conveying means positioned on the downstream side of the cut portion And a low-speed conveying means for conveying the cut sheets in a tiled state, and a stack unit for stacking the cut sheets. Here, the high speed conveying means includes a first air blow located on the lower side, an upper first vacuum drum facing the first air blow, and an upper second vacuum drum located on the lower side facing the low speed conveying means. Yes. Separation protrusions (for example, brushes) are arranged on the outer periphery of the upper second vacuum drum in parallel with the rotation shaft, and the rear edge of the cut sheet is pushed down by the separation protrusions so that the cut sheet is removed from the high-speed conveying means. Transfer to a low-speed transport means and put it in a tiled state.

  In the present invention, a box-shaped first air guide extending in the paper width direction is installed above the running web or cut paper between the cutter cylinder and the upper first vacuum drum. Here, the air guide is positioned such that its bottom surface is inclined forward and downward in the running direction of the web or cut sheet. Therefore, the air guide may be installed obliquely, or an air guide having a slope only on the bottom surface may be used. On the bottom surface of the air guide, a large number of nozzle holes for blowing out air in a flat direction forward are formed in a distributed manner. The inclination angle of the bottom surface of the air guide is set to 10 to 20 degrees (typically about 15 degrees). Accordingly, the air is blown forward and downward (along the bottom surface of the air guide).

  In addition, a box-shaped second air guide extending in the paper width direction is also slightly above the traveling web or cut paper between the upper first vacuum drum and the upper second vacuum drum, almost parallel to the surface of the web or cut paper. Install through a gap. A large number of nozzle holes for blowing air forward are also formed in a distributed manner on the bottom surface of the second air guide.

  With this configuration, the web or the cut sheet is in a state where it travels being sandwiched between the air layer formed by the lower air blow and the air layer formed by the first and second air guides, and is prevented from jumping up and fluttering. It is possible to proceed in the direction of the tangential line, etc., so that a stable running state can be maintained and paper jams can be prevented. In particular, the first air guide suppresses the leading end of the traveling web from greatly jumping, and prevents damage due to a collision with the upper first vacuum drum and a paper jam. The reason why the inclination angle of the bottom surface of the air guide is set to 10 to 20 degrees is that such an inclination angle is particularly effective for preventing damage to the leading edge of the traveling web and preventing paper jams.

  First, an outline of the entire theta for a printing press will be described. FIG. 1 shows an overall configuration of an example of a printing machine sheeter. The printing machine sheeter includes an infeed unit 10 that captures a web discharged at high speed from an offset rotary printing press (not shown), a cut unit 12 that cuts the captured web 11 into sheets of a predetermined size, A high-speed conveying means 13 provided on the downstream side of the cutting section 12, a low-speed conveying means 14 for conveying the cut sheets in a tiled state, and a stack section 16 for stacking the cut sheets 15 are provided. It has been broken. The high speed conveyance means 13 and the low speed conveyance means 14 are shown in FIG.

  The infeed unit 10 has a web take-in mechanism composed of a plurality of free rollers, draw rollers, nip rollers, and various sensors, and is a portion that appropriately feeds the web 11 discharged from the rotary printing machine at a high speed to the cut unit 12. is there. The cutting part 12 has a lower fixed blade 18 and a rotary blade 20 mounted on an upper cutter cylinder 19, and cuts the web 11 into sheets of a predetermined size by rotating at the same speed as a rotary printing press. It is a part to do. The next high-speed conveying means 13 mainly includes a lower first air blow 21, an upper first vacuum drum 22, an upper second vacuum drum 23, and the like. This is a portion that improves the cutting accuracy and presses the trailing edge of the cut paper after cutting to the low-speed conveying means 14 side with the peeling protrusion 24 that rotates synchronously.

  The low-speed conveying means 14 hangs a vacuum belt 28 between the front tip pulley 25 and tension pulley 26 and the rear vacuum drum 27, installs a vacuum box 29 on the inner upper side of the vacuum belt 28, and The second air blow 30 is installed. As a result, the speed of the cut sheet is reduced to about 1/10 to 1/20 of the web line speed. The cut sheets pressed by the peeling projections 24 are partially overlapped with each other, and about 40 mm on the rear end side of the cut sheet is adsorbed by the vacuum belt 28, while the upper surface of the front end of the cut sheet is second upper air blow It is pulled by the Coanda effect by 30 and is sequentially conveyed to the next stack unit 16.

  The stack unit 16 includes two bar-shaped paper guides 34 erected at the entrance, two exit joggers 35 positioned at the exit to face the paper guides 34, and left and right in the running direction of the cut sheet. A pair of variable-width side joggers 36 are provided, and the cut sheets entering the stack unit 16 are aligned and stacked on a pallet 37 positioned below. The pallet 37 is installed on the main pile raising / lowering plate 38 located at the bottom of the stack part 16 and is driven by the main pile raising / lowering mechanism. As a result, the upper surface level of the cut paper 15 on the pallet 37 can be automatically lowered while keeping the surface constant.

  A temporary stacking fork 42 is located below the vacuum box 30 of the low speed conveying means 14. The temporary stacking fork 42, when taking out the main pile (cut sheets stacked on the pallet), is inserted into the stack portion and temporarily receives the cut paper being conveyed, while the main pile is taken out together with the pallet. Next, a new pallet can be installed in the stack.

  Next, the high-speed transport means 13 constituting the main part of the present invention will be described in more detail with reference to FIG. As described above, the high-speed conveying means 13 is located on the downstream side of the cut portion 12. The first air blow 21 located on the lower side, the upper first vacuum drum 22 facing the first air blow 21, and the downstream side thereof. An upper second vacuum drum 23 is provided on the side facing the vacuum drum 27 of the low-speed conveying means. Further, in the present invention, a box-shaped first air guide 50 extending in the paper width direction is installed above the traveling web or cut paper between the cutter cylinder 19 and the upper first vacuum drum 22, and the upper first vacuum drum 22 A box-shaped second air guide 52 extending in the paper width direction is installed above the traveling web or cut paper between the upper second vacuum drums 23. FIG. 4 shows the first air guide 50 and the second air guide 52 in a plan view. A first entrainment prevention plate 54 is provided on the downstream side in the vicinity of the upper first vacuum drum 22, and a second entrainment prevention plate 56 is provided on the downstream side in the vicinity of the upper second vacuum drum 23 (FIG. 2).

  The first air blow 21 is inclined slightly downward from the position about 3 mm immediately below the web or cut paper on the downstream side of the fixed blade 18 of the cut portion 12, almost horizontally or toward the flow direction of the web or cut paper. Is provided. Although square pipe-like air blows divided into 8 to 10 in the width direction may be arranged with a slight gap, in this embodiment, one box-like air blow without division is used. The length with respect to the cut sheet flow direction is roughly up to the rear of the upper first vacuum drum 22, but the upper surface extends as a guide plate 21a to the vicinity of the upper second vacuum drum 23. A large number of air outlets 21b are formed on the upper surface of the first air blow 21 in the running direction of the web, and air is blown from a blower (not shown) through a duct 58 toward the flow direction of the lower surface of the cut sheet from each air outlet 21b. A flat, high-speed air flow. Due to the Coanda effect of this high-speed air flow, the cutter cylinder 19 conveys the leading end of the web that is about to spring up in the direction of rotation to the first air blow 21 in the downstream direction. Here, in the section near the cutter cylinder between the cutter cylinder 19 and the upper first vacuum drum 22 and in the section near the upper first vacuum drum between the upper first vacuum drum 22 and the upper second vacuum drum 23, The outlets 21b are distributed in 10 to 12 rows.

  The first air guide 50 has a box shape extending in the paper width direction, and is positioned between the cutter cylinder 19 and the upper first vacuum drum 22 on the upper side facing the lower first air blow 21 and has a bottom surface. Is installed so as to incline forward and downward in the running direction of the web or cut paper (at an inclination angle of 10 to 20 degrees). On the bottom surface of the first air guide 50, a large number of nozzle holes 50a for blowing air forward are formed in a distributed manner. Air is blown from a blower (not shown) through the duct 50b, and a flat high-speed air flow is blown out from each nozzle hole 50a along the bottom surface of the air guide (that is, forward and downward).

  The front end of the web that is going to spring up with the rotation of the cutter cylinder 19 is attracted by the first air blow 21, but even if it is not attracted by the paper quality, paper thickness, operating conditions, etc. Since the high-speed airflow is blown out from each nozzle hole 50a, it is suppressed by the airflow generated so as to flow from the vicinity of the cutter cylinder 19 toward the nozzle hole 50a in the direction of each nozzle hole 50a, and guided downward and forward. Then, the web or the cut sheet is sandwiched between the air layer formed by the first air blow 21 and the air layer formed by the first air guide 50 and guided to the upper second vacuum drum 22. In order to make the guide function more effective, a guide plate 50 c extending to the very vicinity of the second vacuum drum 22 is provided at the tip of the first air guide 50.

  Next, the upper first vacuum drum 22 is positioned on the web or cut paper on the downstream side of the cut portion 12, and includes a rotating vacuum drum main body 60, a hollow fixed shaft 61, and the like. A large number of suction holes 62 are opened on the surface of the vacuum drum main body 60 and penetrate to the inside. The hollow fixed shaft 61 penetrates a dozen or more vent holes 62 in a straight line in the axial direction, and two grooves parallel to the axial direction are provided on both sides thereof. A separator 64 is inserted into the groove via a wave spring 63. One space is formed by the separator 64 and the labyrinth seals on both sides, and a duct from the exhaust fan is connected to one open end of the hollow fixed shaft 61. The web or cut paper is adsorbed through the suction hole of the vacuum drum main body 60 within the range of the vent hole 62 of the hollow fixed shaft 61 and both separators 64 by the operation of the exhaust fan. There is no suction from most suction holes that are not in communication with the vents.

  The upper first vacuum drum 22 is rotated at a peripheral speed about 1.5% faster than the line speed by the drive timing pulley. The front end of the web that has passed through the cut portion 12 is sent to the downstream side while being adsorbed by the vacuum drum main body 60. At this time, since the peripheral speed of the upper first vacuum drum 22 is slightly higher than the web line speed, the web is tensioned. Therefore, since the cut portion 12 cuts, the size of the cut sheet is always constant. In the cut paper, the peripheral speed of the upper first vacuum drum 22 is faster than the web speed, so that the distance between the cut paper and the web tip is little by little. This eliminates the interference between the cut paper and the web at the cut paper transfer position by the separation projection 24.

  In addition, 20 or more concave grooves for preventing winding are provided on the outer periphery of the vacuum drum main body 60 so that the front end of the web moves straight in cooperation with the first winding preventing plate 54. The first winding prevention plate 54 is located immediately downstream of the upper first vacuum drum 22, and the tip of the web is wound around the vacuum drum main body 60 by inserting the tip of the comb portion into the concave groove of the vacuum drum main body 60. It is carried on the high-speed air flow of the first air blow 21 while being transported in the direction of the upper second vacuum drum 23 by the Coanda effect while preventing it from going upward.

  Further, the second air guide 52 has a box shape extending in the paper width direction, and a slight gap is provided between the upper first vacuum drum 22 and the upper second vacuum drum 23 substantially in parallel with the surface of the web or cut paper. Installed above. The second air guide 52 is located immediately above the portion of the guide plate 21 a of the first air blow 21. A number of nozzle holes 52 a for blowing air forward are also formed in a distributed manner on the bottom surface of the second air guide 52. Air is blown from a blower (not shown) through the duct 52b, and a flat high-speed air flow is blown out from each nozzle hole 52a along the bottom surface of the second air guide (that is, forward). The cut sheet that runs at high speed is sandwiched between the air layer formed by the lower air blow 21 and the air layer formed by the second air guide 52, and is guided to the upper second vacuum drum 23 without fluttering. The second air guide 52 is also provided with a guide plate 52c on the downstream side, thereby improving the guide efficiency.

  The upper second vacuum drum 23 is provided on the downstream side of the upper first vacuum drum 22 at a position within the cut sheet length from the fixed blade 18 of the cutting portion 12. The second vacuum drum 23 includes a vacuum drum main body 65, a peeling projection 24, a hollow fixed shaft 66, and the like. On the surface of the vacuum drum main body 65, a number of suction holes 69 are opened and penetrated to the inside except for the position of attaching the peeling projection. The hollow fixed shaft 66 has ten or more vent holes penetrating in a straight line in the axial direction, and two grooves parallel to the axial direction are provided on both sides thereof. A separator 75 is accommodated in the groove via a wave spring 74. One space is formed by the separator 75 and the labyrinth seals on both sides, and a duct from the exhaust fan is connected to one open end of the hollow fixed shaft 66. The web or cut paper is adsorbed through the air holes 70 of the hollow fixed shaft 66 and the suction holes within the range of both separators 75 by the operation of the exhaust fan. Suction from most suction holes that do not communicate with the vent holes does not occur.

  The upper second vacuum drum 23 rotates at a peripheral speed about 2% faster than the web line speed by the drive timing pulley. The front end of the web that has passed through the cut portion 12 is sent to the downstream side while being adsorbed by the upper first vacuum drum 22, and then adsorbed by the upper second vacuum drum 23, and is further cut by the cut portion 12 in a tension state. . The upper second vacuum drum 23 and the upper second vacuum drum 23 together with the intermediate tension at the upper first vacuum drum 22 are cut while being more reliably pulled, so that the cutting accuracy is ensured in a stable form.

  A second anti-winding plate 56 is also located immediately downstream of the upper second vacuum drum 23, thereby preventing the tip of the web or cut paper from going upward while being wound around the vacuum drum main body 65. 2 The cut paper is conveyed above the stack portion by the Coanda effect that allows the air blow 30 to be smoothly delivered and sucked by the high-speed air flow of the second air blow 30.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to such a configuration. A specific configuration (for example, an infeed unit, a cut unit, a low-speed conveying unit, etc.) of the premise printer theta may be arbitrary. The structure and mounting angle of the air guide, the number of air nozzles, the arrangement status, and the like can be changed as appropriate.

Explanatory drawing which shows the whole schematic structure of an example of theta for printing machines. The schematic block diagram of the high-speed conveyance means and low-speed conveyance means. Detailed explanatory drawing of a high-speed conveyance means. The top view of an air guide.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Infeed part 11 Web 12 Cut part 13 High-speed conveyance means 14 Low-speed conveyance means 15 Cut paper 16 Stack part 19 Cutter cylinder 21 First air blow 22 Upper first vacuum drum 23 Upper second vacuum drum 37 Pallet 42 Temporary stacking fork 50 First 1 air guide 52 2nd air guide

Claims (3)

An infeed unit that takes in the web, a cut unit that cuts the web into sheets of a predetermined size with a cutter cylinder, a high-speed conveyance unit that is located downstream of the cut unit, and the cut sheets are conveyed in a stacked state. A low-speed conveying means; and a stack portion for stacking cut sheets, wherein the high-speed conveying means includes a lower air blow having a plurality of air outlets on the upper surface for forming an air flow in the web running direction, and an upper first vacuum opposed thereto. A drum and an upper second vacuum drum positioned on the upper side facing the low-speed conveying means on the downstream side thereof are transported while pulling the front end of the web by the air flow by the lower air blow, and are arranged on the outer periphery of the upper second vacuum drum For printing presses that push down the trailing edge of the cut sheet with the peeling protrusion and transfer the cut sheet from the high-speed conveyance means to the low-speed conveyance means to put it in a tiled state In over data,
Above the traveling web or cut sheet between the cutter cylinder and the upper first vacuum drum, located a box-like air guide extending in the sheet width direction, the air guide is inclined such bottom is lower toward the downstream side installation is, and the with a number of the nozzle holes for blowing air guide d a is the bottom surface flat in the running direction of the web or cut sheet is dispersed form, first above the downstream end of the bottom surface of the air guide and guide plates extending to opposed the vicinity of the lower air blow of the vacuum drum is provided, downstream while suppressing an air flow for blowing the web leading end to be Haneagaro with the rotation of the cutter cylinder from the nozzle holes of the air guide and guided to the guide web or cut sheet is traveling to the upper first vacuum drum is sandwiched by the air layer due to the air layer and the air guide by the lower air blow Theta for a printing press, characterized in that the the As.   The theta for a printing press according to claim 1, wherein an inclination angle of a bottom surface of the air guide is 10 to 20 degrees. A box-shaped second air guide that extends in the paper width direction above the running web or cut paper between the upper first vacuum drum and the upper second vacuum drum has a slight gap substantially parallel to the surface of the web or cut paper. The printing machine sheeter according to claim 1 or 2, wherein a plurality of nozzle holes are formed on the bottom surface of the second air guide to blow out air in the running direction of the web or cut paper in a distributed manner.

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