DE2235768C2 - Control system of a convertible multi-color sheet-fed rotary offset printing machine - Google Patents

Description

The invention relates to a control system of a convertible. Multi-color sheet-fed rotary offset printing machine for either perfecting or perfecting with a turning drum and one made of part registers existing shift registers, with the sub-registers query stages for actuating the printing units are assigned to the individual functional groups of the printing units at the correct time.

For actuation of the printing units or the individual functional groups of the printing units in the correct sequence control systems are used in which the initiation command (on-off) is synchronized with the respective revolution and phase within the revolution at which the command is to be executed (DE-OS 22 20 601).

jo With these control systems there is a constant allocation a certain revolution and a certain phase to the respective initiation command Actuation of the function group to be controlled.

In printing machines for optional perfecting and perfecting printing is a control system with constant Assignment cannot be used.

With these machines, the sheet is transferred from the printing cylinder of one of the straight printing machines Printing unit via a transfer drum to the printing 4ü cylinder of the next printing unit, the Sheet is passed with its leading edge in the transfer area of the cylinder and the drum.

When switching to front and back printing, the end of the sheet is taken from the impression cylinder of one printing unit transferred via the transfer drum, which is equipped as a turning drum, to the next printing cylinder, d. H. there is a phase shift in the temporal sequence of movements, which is different due to the sheet format to be processed is not constant. A similar variable phase shift results also with the optional use of a drying unit or another inserted processing station.

The object of the invention is to compensate for the change from perfect to perfect resulting phase shifts in the work cycle of the printing units following the turning drum.

According to the invention, the object is achieved by the characterizing part of claim 1, with further selections) arrangements in the characterizing part of claims 2-7 are described.

In the following, the invention will be based on an exemplary embodiment explained. It shows

Fig. I Principle of a printing machine for optional (i5 perfecting.

Fig. 2 Principle of the shift register with an intermediate shift register.

F i g. 3 Principle of the shift register with query

window displacement,

F i g. 4 shift registers with intermediate clocking,

F i g. 5 control level.

The sheet 6 fed to the feed drum 3 via the feed table 1 and the pre-gripper 2 is attached to the first Hand over gripper system 4 of the printing cylinder 5 of the omen printing unit. After being in the first printing unit has been printed, it is attached to the first gripper system 7 of the turning drum 8 and from there the first gripper system 9 of the printing cylinder 10 of the second printing unit pass over.

If the machine has been switched to perfecting, the sheet is turned in a known manner. For this purpose, the sheet 6 is not attached to the first gripper system 7 transferred to the turning drum 8, but continued until the end of the sheet at the transfer point lies

Now the end of the sheet is removed from the first suction system 31, which is in the transfer point has been moved, detected and after the gripper systems 7 have been put together; 11 to the first gripper system 7 passed. All firing operations to actuate the one lying after the turn of the bow Assemblies are phase-shifted by the angle of rotation corresponding to the respective sheet format.

In the case of straight printing, the signal processing takes place by means of a shift register 12.1 ; 12.2. The shift register is divided into bits, the bits required are query levels 13.1; 13.2 assigned to the actuation of the individual function groups.

The first bit of the shift register is a clock signal input 14 and two information inputs 15.1; 15.2 assigned for the arc signal. The query levels 13.1; 13.2 can be designed as clocked or non-clocked query levels.

Changeover variant 1

When changing over to front and back printing, the shift register 12.1; 12.2 divided into two sub-registers 12.1 and 12.2 . The sub-register 12.1 is used to operate the function groups which are located in front of the turning drum and the sub-register 12.2 is used to operate the function groups which are located after the turning drum.

The shift clock and information transfer between the registers 12.1 and 12.2 is interrupted by means of a first key switch 16 and at the same time the information outputs of the last bit of the register 12.1 are connected to the information outputs of an intermediate register 17. The outputs of the intermediate register 17 are connected to the inputs of the sub-registers 12.2 .

The clock signal input 18 of the intermediate register 17 is either connected to the clock signal 14 of the shift register 12.1; 12.2 or connected to a known additional pulse stage, not shown.

The following sub-variants can occur with this variant.

Sub-variant 1.1

The clock inputs 14 and 18 are connected to one another; the intermediate register 17 is designed according to the integer part of the quotient of the phase shift and the clock frequency and the query stage 13.2 as a clocked query stage. Example: phase shift 130 °, clock frequency 30 °; This results in an intermediate register 17 with 4 bits and a residual phase shift at the clock input 19 of the interrogation stage 13.2 compared to straight printing of 10 °.

Sub-variant 1.2

If the clock frequency is correspondingly low, so that only a very small residual phase shift remains, this remainder can also remain unbalanced ίο or due to the mechanical design of the actuation of the functional groups are balanced.

Sub-variant 13

Formation of the intermediate register 17 according to the integer quotient from the phase shift and clock frequency and compared to the clocking at the clock input 14 phase-shifted clocking by the remaining amount at clock input 18.

The format-dependent change in the phase shift (approx. 100 ") with variant 1, either the query level is changed by changing the timing or the intermediate register balanced.

In variant 1, the query levels for perfecting and perfecting are subordinate to the same bit.

Changeover variant 2

When switching to perfecting, the interrogation stages 13.2 which actuate the function groups after the sheet is turned are shifted by the amount of the phase shift, ie appended to the corresponding subsequent bits.

Here, too, there are various sub-variants.

Sub-variant 2.1

The query stages 13.2 are shifted by the quotient of the phase shift and clock frequency, ie for example from the seventh bit to the tenth bit and the residual phase shift is achieved by clocking the query stage 13.2 out of phase with the front print. The changeover to the corresponding bit takes place by means of the third key switch 20.

Sub-variant c 2.2

so At a low clock frequency, the residual phase shift can also remain unbalanced or due to the mechanical actuation of the functional groups are compensated.

Sub-variant 3

When switching to front and back printing, the shift register 12.1; 12.2 separated by means of the second key switch 21, as in variant 1, and the partial register 12.2 is clocked with the phase shift that occurs during perfecting via the clock input 27.

The pulse stage which supplies the phase-shifted clock signals is known.
h5 A control stage 23 is arranged upstream of the respective query stages 13.2 in order to determine a sheet loss after the sheet has been turned.

The control level consists of an I \ nr \ -C \\ pA ">&.

with two inputs, the first input is formed by the scanning head 25 to determine the sheet loss and the second input via an inverter 26 from the L output of the interrogation stage 13.2.

The following signal definition applies: ^r ,

If the sheets are in order, both the interrogation stages and the scanning head carry an O signal.

Shutdown only occurs if the scanning head detects an arc loss and thus an I. signal leads and the query stage O signal, d. H. Arc should be ok be present, leads. Only in this case does the output of the control stage carry an L-signal and reset takes place the query level. The reset reverses the signal position. thereby also the blocking of the Actuation is automatically canceled. 15th

For this purpose 3 sheets of drawings

Claims (7)

Patent claims: 1. Control system of a convertible multi-color sheet-fed rotary offset printing machine for optional straight or perfecting with a reversing drum and a shift register consisting of sub-registers, the sub-registers being assigned query stages for operating the printing units or the individual functional groups of the printing units at the correct time , characterized in that between a sub-register (12.1 ) switching the printing units or functional groups before the turning drum (8) and a sub-register (12.2) of the shift register (12.1; 12.2) which resounds the printing units or functional groups after the turning drum (8), there is an output cable with the Intermediate register (17) connected to the inputs of the subordinate sub-register (12.2) to compensate for the variable phase shift that occurs when the machine is changed over is inserted, and the inputs of the intermediate register (17) to the outputs via a first key switch (16) to be actuated during the changeover n of the upstream sub-register (12.1) are connected. 2. Control system of a convertible multi-color sheet-fed rotary offset printing machine for optional straight or perfecting with a reversing drum and a shift register consisting of sub-registers, the sub-registers being assigned query stages for operating the printing units or the individual functional groups of the printing units at the correct time , characterized in that the interrogation stages (13.1; 13.2 ) switching the printing units or functional groups after the turning drum (8) to compensate for the variable phase shift occurring when changing over the turning drum (8) via third key switches (20) with the subsequent sub-register which are to be actuated when changing over (12.2) are connected. 3. Control system according to claim I or 2, characterized in that the phase shift is the Adjustment angle of the turning drum (8) is analogous. 4. Control system according to claim 1 or 2, characterized in that the number of bits of the intermediate register (17) or the number of bits between the two switch positions of the third key switch (20) is analogous to the integer quotient of phase shift and clock frequency. 5. Control system according to claim 4, characterized in that the query stages (13.2) of the converted and the following units are designed as clocked query stages, the clock signal inputs (18) with an additional pulse stage, which clock signals with the non-integer part of the quotient from phase shift and clock frequency provides shifted amount, are connected. 6. Control system according to Claim 4, characterized in that a clock signal input (18) of the intermediate register (17) or a clock signal input (27) of the first bit of the sub-register (12.2) of the shift register (12.1; 12.2) which resounds the functional groups of the converted and the following units ) with an additional pulse stage, which phase shifts analogous to the respective phase shift. bene provides clock signals, is connected 7. Control system according to claim 1 or 2, characterized in that a first input (22) of the query stage (13.2) is an output of a control stage (23). consisting of an AND element (24), the first input of which is formed downstream of a scanning head (25) for determining the sheet loss in the converted and subsequent units and the second input of which is formed by the L output of the interrogation stage via an inverter (26)