GB2253592A

GB2253592A - Rotary sheet printing press.

Info

Publication number: GB2253592A
Application number: GB9200872A
Authority: GB
Inventors: Willi Jeschke; Anton Rodi
Original assignee: Heidelberger Druckmaschinen AG
Current assignee: Heidelberger Druckmaschinen AG
Priority date: 1991-01-20
Filing date: 1992-01-16
Publication date: 1992-09-16
Also published as: GB9200872D0; JPH04308752A; DE4102472A1; FR2671759A1

Description

1 e25^,5'r2 Rotary printing press for the processing of sheets The

invention relates to a rotary printing press for the processing of sheets with a drive unit, with at least one printing unit with an impression cylinder, with first sheet-transfer means, positioned before the printing unit, for loading the impression cylinder with sheets removed singly from a pile and aligned in the longitudinal and transverse directions, with second sheet-transfer means, positioned after the printing unit, for accepting printed sheets from the impression cylinder and for delivering them, with a first geardrive section for driving the printing unit, with a second gear-drive section for driving the first sheettransfer means and with a third gear-drive section for driving the second sheet-transfer means.

For ordinary operating conditions, known multi-unit printing presses with two or more in-line printing units, which are mechanically connected to one another by means of intermediate gear drives, are provided with a main drive unit which acts, for example, on a middle printing unit and which drives all printing units of the printing press, while additional drive units are provided for the other printing units, which can be decoupled from one another and from the middle printing unit, saild other printing units each being able to be driven separately by said additional drive units for the purpose of maintenance and setting-up operations. Such multi-unit printing presses are known, for example, from DE-OS 15 61 030. If in the engaged (coupled) operating state, the additional drive units can also be used to support the main drive unit in order in this manner to accept some of the resistance offered by the respective printing units. This makes it possible to reduce the loads acting on the intermediate gear drives and on the corresponding couplings.

From DE-PS 487 530 it is known, for the sheet delivery of a high-speed cylinder press, to provide a conveying apparatus which moves independently of the transport of the sheets and by means of which the printed sheets are removed from the high-speed press. Said conveying apparatus is an assembly of tapes, positioned after a chain delivery, of a so-called Babcock printed-side-up delivery, with the sheets that have been released from the chain delivery being deposited on said assembly of tapes. In this connection, the printed-side-up delivery is disposed in such a manner that the sheets that are deposited on its tapes are transported transversely to the previous direction of sheet transport.

In order to prevent torque surges, occurring in a folding machine in time with the blade, from reacting on the printing units, it is known in reelfed gravure presses to decouple the drive of the folding machine from that of the printing units, to drive it separately and to synchronize it with the preceding printing unit by means of a synchro control ("Multi- Motor Drive for Rotary Printing Presses", Siemens-Zeitschrift 51 (1977) No. 5, p. 387-394).

The invention proposes a rotary printing press whose advantages consist, firstly, in that there is a reduction in the load on a gear train of intermeshed driving gears, particularly in multi-colour rotary printing presses, and, secondly, in that more printing units can be driven with basically the same loading on gear trains.

Further advantages consist in that mechanically decoupled functional units can be set without major effort to defined operating states and in that it is possible to dispense with certain mechanical assemblies that are required in conventional rotary printing presses of the aforementioned kind.

For example, if there is mechanical decoupling of a suction head, used to single the piled sheets, from driving means for the remainder of the first sheettransfer means, it is possible to make adjustments to the suction head with the printing units stationary and to dispense with a valve for suction air for supplying the suction head.

A further mechanical assembly that can be dispensed with if use is made of the invention is, for example, an assembly, operating usually with adjustable chain drive, for setting the mutual phase positions of the first printing unit and of the first sheet-transfer means.

Specimen embodiments of the invention are described in greater detail in the following with reference to the drawings, in which: Figs. la and lb together comprise Fig. 1 which shows a diagram of a delivery module, said delivery module being mechanically decoupled from the drive unit of a printing-unit module and being equipped with an additional drive unit; Figs. 2a and 2b together comprise Fig. 2 which shows a developed view of drive-gear trains for a module arrangement according to Fig. 1; Fig. 3 shows a block diagram of a known analogue standard rotational- speed feedback control for 4 direct-current shunt-wound motors and a superimposed, known hybrid angle- position feedback control for coordinating the mutual phase positions of a drive unit and of an additional drive unit according to Fig. 1; Fig. 4 shows a diagram of a feeder module, said feeder module being mechanically decoupled from the drive unit of a printing-unit module and being equipped with an additional drive unit; Fig. 5 shows a diagram of a feeder module, said feeder module being mechanically decoupled from the drive unit of a printing-unit module and being equipped with additional drive units for mechanically decoupled partial sections of the first sheet-transfer means.

The part of a sheet-processing rotary printing press shown schematically in Fig. 1 is divided into printingunit modules 1, 2 and a delivery module 3. The printing-unit modules each comprise a transfer cylinder 4, 5, an impression cylinder 6, 7, a rubber-blanket cylinder 8, 9 and a plate cylinder 10, 11. The associated inking and damping units as well as possible varnishing units and washing apparatuses are, for the sake of clarity, not shown.

The cylinders of each printing unit are intermeshed via gearwheels in the assignment shown in Fig. 1. Likewise, there is intermeshing between the impression cylinder of a preceding printing unit and the transfer cylinder between the preceding and following printing units. Furthermore, the gearwheel of the transfer cylinder 4 meshes with the pinion 12 of a drive unit 13.

- The printing-unit module 2 is adjoined by a delivery module 3 with a chain drive 14, the grippers 15 of which accept the printed sheets f rom the grippers 16 of the impression cylinder 7 of the preceding printingunit module.

According to Fig. 2, there is no torque-transmitting connection between the impression cylinder 7, borne by the impress i on-cyl inder shaft 22, and the chain drive 14. Rather, the chain drive is assigned an additional drive unit 18, which, through the intermediary of a pinion 19, drives a gearwheel 21 connected to the chainwheel shaft 2d.

The impression-cylinder shaft 22 of the printing unit 2 immediately preceding the delivery module, and the chain-wheel shaft 20 are each assigned an incremental pickup 23, 34. Said pickups serve to measure the angleof-rotation deviations between the aforementioned shafts 20 and 22. With the aid of the signals from said pickups and with the aid of a known hybrid angleposition feedback control, which processes said signals and which is superimposed in known manner on a likewise known analogue standard rotational-speed feedback control, it is possible to achieve highly accurate synchronization of the impression cylinder 7 and of the chain-wheel pair 17, 17'.

Direct-current shunt-wound motors 25, 26 are provided as motors for the two drive units, as is usual for the driving of printing presses. The gearing-related conditions for the agreement between the circumferential speed of the impression cylinder 7 and the path speed of the grippers 15, required for correct sheet transfer to the chain delivery, given identical rotational speeds of said two motors, can be created by a suitable choice - 6 of the pitch-circle diameter of the chain-wheel pair 17, 17' and a suitable transmission ratio between the drive shaft of the motor 26 and the chain-wheel shaft 20.

With reference to the example of drive units equipped with direct-current shunt-wound motors 25, 26, Fig. 3 shows, in the form of a block diagram, the control means for coordinating the mutual phase positions of drive unit 13 and additional drive unit 18 by synchronization of the chainwheel shaft 20 with the impression-cylinder shaft 22.

In the specimen embodiment, the motor 25 driving the printing units serves as the master drive and the motor 26 driving the delivery serves as the slave drive. The two motors are each connected to the mains 29 via an analogue rotational-speed feedback-control apparatus 27, 28. By means of said apparatuses, the analogue signal picked off by a pickup 32 for the rotational-speed reference variable is compared with the rotational- speed actual value of the respective motor 25, 26, obtained with the aid of a tachometer generator 30, 301, and, from this, a control voltage is derived for a converter 31, 31', said converter 31, 31' feeding the respective motor.

In the block diagram, the shafts 22 and 20 to be synchronized are schematically connected, on the one hand, to the motors 25 and 26 and, on the other hand, to the associated incremental pickups 24 and 23.

The construction and operating principle of the angleposition feedbackcontrol apparatus 33 need not be explained in greater detail here, because this is a known apparatus that is described in detail in the publication "Multi-Motor Drive for Rotary Printing Presses", Siemens-Zeitschrift 51 (1977) No. 5, p. 387394.

The angle-position feedback-control apparatus 33 processes the signals from the incremental pickups 23, 24 to form an angle-correction signal which is additionally applied via the line 34 to the comparator 35 of the rotation-speed feedback-control apparatus 28.

The chain-wheel pair 17, 17' is part of the third geardrive section for driving the second sheet-transfer means in the form of a chain delivery. In the previously described specimen embodiment, said third gear-drive section is mechanically decoupled in its entirety from the first geardrive section, which, in the example, is formed by a gearwheel train for driving the cylinders of the two printing-unit modules 1 and 2. The gearwheels of said gearwheel train, partially reproduced in Fig. 2, are each coaxial with the cylinders of the printing-unit modules.

Provided in the specimen embodiment shown in Fig. 4 is a feeder drum 37 which is mechanically coupled to an impression cylinder 38 and which, in the initially described sense, is to be counted as part of the first sheet-transfer means. Remaining partial sections of the second gear-drive section are mechanically decoupled from the feeder drum 37 and thus from the drive unit 13 (see Fig. 1) and are driven by an additional drive unit 44. Consequently, connected before a printing-unit module 36 is a feeder module 39 which, as a partial section of the second gear-drive section and being mechanically decoupled from the drive unit 13, comprises, in particular, a chain drive 40 for driving a suction head 41 for singling the sheets from a pile 42 and a tape drive 43 for transporting the sheets towards the feeder drum 37, which serves as the feeding means.

Further details of the drive of the suction head 41 emerge, for example, from DE-PS 19 29 714, with the result that there is no further discussion of it here.

The gear-drive parts for operating front and side lays for aligning the sheets supplied to the feeder drum 37 as well as said guide lays themselves are not shown. Further details in this respect can be obtained, for example, from DE-PS 251 468 with regard to the front lays and, for example, from DE-PS 22 21 186 with regard to the side lays.

Accordingly, the movements of the aforementioned guide lays are each derived from a rotating part of a printing unit. While maintaining this, in the specimen embodiment shown in Fig. 4, merely that partial section of the second gear-drive section for driving the first sheet-transfer means for loading the impression cylinder with sheets removed singly from the pile and aligned in the longitudinal and transverse directions is disposed without power transmission from the drive unit 13 and is connected to an additional drive unit 44 which serves to drive the suction head 41 and transport tapes 45 which transport the sheets, removed singly by means of the suction head 41, towards the feeder drum 37.

The means for synchronizing said partial section of the second gear-drive section with the first gear-drive section may be the same as those for synchronizing the chain drive 14 of the delivery module 3 with the first gear-drive section.

Within the framework of the invention, the movements of the guide lays may also be derived from a rotating part of the second gear-drive section. . In particular, these movements may be picked off from the rotational movement of the feeder drum 37, which is likewise part of those sheettransfer means by means of which the impression cylinder 38 is loaded with sheets.

In a further specimen embodiment (not shown in the drawings), there is then a torque-transmitting connection between all partial sections of the second gear-drive section, with parts of said gear-drive section serving to drive the guide lays and with said second gear-drive section being mechanically decoupled in its entirety from the first gear-drive section and being connected to the additional drive unit 44. In this regard, the mechanical decoupling.is performed between the impression cylinder 38 and the feeder drum 37.

As for the rest, with regard to the direct transfer of the sheets to the impression cylinder 38, the invention is not limited to the means of feeding used in the previously described embodiments being in the form of a feeder drum.

Whereas, in the embodiment shown in Fig. 4, gear-drive means of a plurality of functional units (in this case of the suction head 41 and of the tape drive 43) of the first sheet-transfer means are combined to form a partial section of the second gear-drive section, said partial section being mechanically decoupled from the drive unit 13, and are driven by a common additional drive unit 44, there is, in the specimen embodiment according to Fig. 5, a further mechanical decoupling to the extent that the second gear-drive section is divided into a plurality of partial sections each equipped with an additional drive unit. In this connection, one of the independent partial sections comprises gear-drive means provided for driving the suction head 41 and is equipped with an additional drive unit 46 provided exclusively for driving said geardrive means. This results, in particular, in the previously mentioned advantages with regard to the adjustment of the suction head 41 and with regard to the possible dispensing with a valve for supplying the suction head 41 with suction air. It will be appreciated that the foregoing has been described by way of example only and that changes can be made without departing from the scope of the invention as defined by the claims.

11

Claims

1 CLAIMS

1. A rotary printing press for the processing of sheets with a drive unit, comprising:

at least one printing unit with an impression cylinder; first sheet-transfer means, positioned before the printing unit, f or loading the impression cylinder with sheets removed singly from a pile and aligned in the longitudinal and transverse directions; second sheet-transfer means, positioned after the printing unit, for accepting printed sheets from the impression cylinder and for delivering them; a first gear-drive section for driving the printing unit; a second gear-drive section for driving the first sheet-transfer means; and a third gear-drive section for driving the second sheet-transfer means; in which at least one partial section of at least one of the gear-drive sections for driving the sheet-transfer means is disposed without power-transmitting means between the partial section and the drive unit and is driven by an additional drive unit; and in which the mutual phase positions of the drive unit and an additional drive unit are coordinated by control means.

2. A rotary printing press according to claim 1, further comprising a delivery module which is mechanically decoupled from the drive unit and which is driven by the additional drive unit.

3. A rotary printing press according to claim 1, further comprising a feeder module which is mechanically decoupled from the drive unit and which is driven by the additional drive unit.

A rotary printing press according to claim 3, further 12 including a suction head for singling the piled sheets, said suction head being mechanically decoupled f rom the additional drive unit of the feeder module and being driven by a further additional drive unit.

5. A rotary printing press substantially as hereinbef ore described, with reference to f igures 1 to 3, or to f igure 4, or to figure 5 of the drawings.