DD157899A1 - METHOD AND DEVICE FOR ARCING IN MULTICOLOR ARC PRINTING MACHINES - Google Patents

Abstract

The invention relates to the sheet turning in multi-color sheet-fed rotary printing presses for printing the sheet back side. The aim of the invention is to ensure a register accurate two-sided printing with high working speeds, while minimizing Druckflaechenverlust. The task is to detect during the movement phase of the largest paper train during Bogenuebernahme the sheet trailing edge of the entire sheet width almost completely over-printing suction section. This is achieved according to the invention in that the sheet trailing edge on the advance printing cylinder is detected by a suction path formed rectilinearly over the entire sheet width by the first suction system and a second suction system and pivoted in the direction of the cylinder interior, with the second suction system halfway for the transfer to the gripper system, the sheet loosens and stops and the sheet is continued by the first suction system and passed to the gripper system.

Description

The invention relates to a method and apparatus for sheet turning in multicolor sheet-fed rotary printing presses.

In perfecting machines that allow a two-sided printing in a sheet pass for the purpose of reducing transfers with only a sheet guiding cylinder between two printing cylinder, the pressure-free sheet trailing edge is removed on the straight printing page with suction from the closed surface of the sheet guiding cylinder upstream impression cylinder. ; ,

Characteristic of the known technical solutions

There are already known sheet guiding cylinder, in which the printed and turned sheet, removed by a suction system from the preceding printing cylinder and passed during des.Einschwenkens to the gripper system (DD-PS 54 703), the disadvantage here is that the Saugersystern large • Intermediate spaces must-must, so that the necessary space is available for the gripper in the sheet transfer. In order to ensure the required holding force of the teat system, it is therefore necessary to make the suction surfaces of the individual teat very wide. This, however, further disadvantages that once the pressure-free space at the sheet trailing edge must be kept wider and on the other hand, that in rigid printing material, during pivoting of the teat system by the existing bending stress, the holding force of the sucker is partially or completely overcome and the printing material therefore shifts or * chatters.

Object of the invention

The aim of the invention is to provide a method and a device for improving the sheet turning operation, whereby a register-accurate two-sided printing is made possible at high working speeds with at the same time minimum printing surface loss.

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Essence of the invention

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The invention has for its object the sheet guiding cylinder in such a way that is detected in the phase of movement of the largest paper train during the sheet transfer, the sheet trailing edge of the entire sheet width almost completely covering the suction path. For this purpose, according to the invention, the sheet trailing edge on the advance printing cylinder formed by a ausdem first suction system and a second suction system, over the entire bow width rectilinearly extending suction path and pivoted toward the cylinder interior, the second sucker sy st em on half Y / eg Transfer to the gripper system lets go of the bow, and stops and the sheet is continued solely by the first suction system and passed to the gripper system "The first yerschwenkbaren suction system is in the space provided for the transfer to the gripper system spaces a second, separately controlled, swiveling suction system assigned "The suckers of the first suction system are mounted on the mounted in the end walls of the sheet guiding cylinder tube. The suckers of the second suction system are rotatably arranged on the tube shaft and connected to each other by a square cross-member. The pivoting movement of the second suction system is controlled by means of a curve attached to the side wall and a mounted on the tube shaft of the sheet guiding cylinder roller lever lever and coupling rods. The common time of the suction start at the sheet takeover for the first suction system and for the second suction system and the time for the Saugende for.das first Saugersystern in the sheet delivery to the gripper system is controlled by a arranged in the sheet guiding cylinder valve. To control the time for the suction of the second Saugersystems the valve is followed by a disc valve. The disc valve is mounted on the tube shaft and forms with a sucker of the second teat system a face-side sealing surface,

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The non-rotatable disc valve has a kidney-shaped opening on the plan side, which cooperates with a lateral bore in the adjacent nipple of the second nipple system and the same is determined by pivoting the suction end.

embodiment

The invention will be explained in more detail below using an exemplary embodiment.

In the accompanying drawings show;

Pig "1 is a schematic representation of a printing unit of a multicolour Bogenrotations- . , printing press

Pig · 2 the sheet guiding cylinder -

Phase of pivoting of the teat system. to the gripper system

Pig · 3 the Bow Guidance Linder -

Phase of the sheet transfer from the suction system to the gripper system and to the subsequent impression cylinder

) 'Pig' 4 the disc valve according to section AA of [ Pig. 5

Pig · 5 like a longitudinal section through the sheet guiding cylinder · "Section B-B of Pig. 3

The sheet 1 to be printed is transferred from the feed drum 2 to the printing cylinder 3 and printed in the contact zone between the latter and the blanket cylinder 4.

When perfecting the "sheet 1 after the first print on the printing cylinder 3 is performed until the .Bogen- ', trailing edge of the sieh over the entire sheet width extending suction section 5 of Bogenführungszyliiiders 6 near the tangent point of both cylinders 6) (Pig, 1) The suction section 5 is formed by a first suction system 7 and a second suction system 8. The first suction system 7 and the second suction system 8 jointly feed the sheet 1 over half the pivoting path (FIG. Then, the second sucker system 8 is released and the pivotal movement is completed * The sheet 1 is then guided to the transfer point 9 to the gripper system 9 (Fig. 3) alone on the second half of the pivoting path through the first suction system 7. The sheet guiding cylinder 6 is constructed so that the tube 10 is fixedly connected on both sides to the pins 11, 12. The end walls 13, 14 are also firmly connected to the tube 10. The sheet guide is mounted 6 in the bearing bushes 15 »16» which are fastened in the side walls 17 »18. The suction cups 19 of the first suction system 7 are rotationally rigidly connected to the tube shaft 20 mounted in the end walls 13. The suckers 21 which form the second suction system 8 are all firmly connected to the square cross member 22. The center of the tubular shaft 20 is also used as the pivoting center for the second suction system 8. Therefore, the respective outer suction cups 21 are provided with a housing 23 in which a bearing bore 24 is provided which serves to guide on the tubular shaft 20. The pivotal movement of the second teat system 8 is generated by the cam 25 mounted on the cam follower 26 attached to the side wall 17 (FIG. 3). The transfer takes place through the roller lever 27 of the one mounted in the end walls 13, 14 Tube shaft 28 is fastened. Two levers 29 mounted on the tube shaft 28 are articulated via the coupling rods 30 to the hubs 31 of two suckers 21. The frictional engagement of the roller 32 of the roller lever 27 to the curve 25 is generated by the mounted in the tube shaft 28 torsion bar 33.

The pivoting movement for each correlatively cooperating teat and gripper systems 7, 9 is determined by the curve 34, the

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mounted on the side wall 18 cam carrier 35 is generated. The transmission takes place by the ball lever and the tooth segments 37 »38, 39, 40. The pivoting of the suction systems 7, 8 must take place in the area of the common bowing from the transfer point to the middle pivoting path, ie within the angle Qf ₇ at absolutely the same speed To achieve this, the curve 25 is formed and adjusted so that the second suction system 8 would precede the first suction system 7 by a small distance. Since an elastic member has been inserted in the motion transmission from the curve 25, with the compression spring 41 interposed on the coupling rod 30, it is possible to apply the second suction system 8 to the first suction system 7 with a pressure determined by the compression spring 41. This measure eliminates unavoidable production tolerances and ensures absolute speed synchronization of the two suction systems 7> 8 in the area of the angle.

The suction air supply of both suction systems 7, 8 takes place from the outside and is supplied via the bore 42 of the pin 11 to the interior · 43 of the pipe 10 and from there via the pipe 44 to the valve 45. The valve 45 controls the time of the common suction start when taking over the trailing edge of the sheet 1 for the first and second suction system 7 »8. Also by the valve 45, the time of the suction end for the first suction system 7 at the end of swinging and transfer to the Gripper system 9 controlled. The valve 45 is fixedly connected to a support wall 46 fixed to the pipe 10. The suction air controlled by the valve 45 passes through the bore 47 into the manifold 48 mounted on the tubular shaft 20 and from there into the interior 49 of the pipe shaft 20. The suckers 19 of the first suction system 7 are connected via the bore 50 with the interior 49 of the tubular shaft 20. Via a second outlet of the valve 45, the disc valve 52 mounted on the tube shaft 20 is connected through the hose line 51. This disc valve 52 and the hub 53 of the adjacent suction device 21 are on the plan side as sealing surfaces

formed through a kidney-shaped opening 54 of the Scheibenventils.52 and through holes 55, - 56, 57, the suction air enters the interior 58 of the Yierkanttraverse 22,. The time of the suction end for the second suction system 8 is determined by the pivot position. When the sheet is taken over, the bore 55 is located in the lower region of the kidney-shaped opening 54. · At the suction end, ie with passage of the angle (FIG. 4), there is no overlap between the bore 55 and the kidney-shaped opening 54 Accordingly, the second suction system 8 is replaced by covering the swivel angle <X.

Broken · Immediately afterwards it comes to a standstill.

The supply of the individual suction cups 21 with controlled suction air takes place through the bores 57, 59 '' leading into the interior 58 of the traverse 22.

Claims (1)

~ 7 - • invention claims 1 # Method for sheet-fed in multi-color sheet-fed rotary printing presses on the principle of trailing edge when transferring from one printing unit to another for the purpose of printing the sheet back, with a suction system, which correlatively with a gripper system cooperates, characterized in that the sheet trailing edge on the advance. Pressure cylinder (3) by a from the first suction system (7) and a second suction system (8) formed, over the entire arc width straight " linig extending suction section (5) is detected and is pivoted in the direction of the cylinder interior, wherein the second suction system (8) half way to handover to the gripper system (9) the sheet (1) goes and stops and the sheet (1) continued solely by the first suction system (6) and transferred to the gripper system (9). 2 »device for sheet turning in multi-color sheet-fed rotary printing presses on the principle of trailing edge when transferring from one printing unit to another, with two arranged in the sheet guiding cylinder, each oscillating sheet holding systems, each of which ). Sucker system decreases the bow from the preceding printing cylinder and the gripper system for forwarding to the ) Gripper system of the subsequent printing cylinder passes, characterized in that the first pivotable Saugersystera (7.) in the space provided for the transfer to the gripper system (9) spaces a second, separately controlled, swiveling suction system (8) is assigned » 3 «Device according to point 2, characterized in that the suckers (19) of the first suction system (7) are mounted on the in the end walls (13, 14) of the sheet guiding cylinder (6) mounted tubular shaft (20) and the suckers (21) of the second suction system (8) rotatable on the tube shaft u. 8th - (2Q) are arranged and connected by the square crossbar (22) « 4 device according to point 2 and 3 characterized in that the second suction system (8) by means of a on the side wall (17) fixed curve (25) and on the tube shaft (20) of the sheet guiding cylinder (6) mounted roller lever (2?) controlled by lever (29) and coupling rods (30) * Device according to points 2 to 4, characterized in that a common time of the start of suction at the sheet takeover for the first suction system (7) and for the second suction system (8) and the time for the suction for the first suction system (7) in the sheet delivery to the gripper system (9) controlling valve (45) in the sheet guiding cylinder (6) is arranged and that a suction of the second suction system (8) controlling disc valve (52) is connected downstream » 6. The device according to item 5, characterized in that the on the tube shaft (20) mounted disc valve (52) and a sucker (21) of the second suction system (8) plane in the contact surface have a seal and that the nichtverdrehbare disc valve (52) on the plan side has a kidney-shaped opening (54) and in the suction (21) of the second suction system (8) by pivoting the same the suction end determining side bore (55) is arranged « Hsarzu ... ^ 3 ...: Be drawings! - 9 -