EP1157830B1 - Device and method for changing the printing image during the operation of a printing press - Google Patents

Description

The present invention relates to the field of offset printing. The concerns The present invention relates to a device for changing a print image Plates in an offset printing press when the printing press is in operation.

Offset printing machines are well known in printing technology. In these devices become a blanket cylinder and an image cylinder or plate cylinder for printing on one side of a material web (e.g. paper) that is in contact with the Blanket cylinder is. The blanket cylinder receives a color image from the image cylinder and transfers this image to the material web. The image cylinder usually includes one a plate carrying a printed image on which the image to be printed is located. The Image cylinder can alternatively be a cassette with imageable material that was previously was imaged or imaged by an imaging device in the printing press becomes. There are various ink fountains and inking rollers as well Moist application rollers for transferring the color to the image-bearing plate or the imageable material used on the image cylinder, thereby creating the image cylinder Color for later transfer of the colored image to the blanket cylinder deliver.

In conventional offset printing machines, every blanket cylinder is usually included connected to a single image cylinder. When in these presses the timing has come to replace the image bearing plate or cassette, either due to of maintenance requirements or because a new image needs to be printed, it is necessary to stop the press. Because a single image cylinder to transfer an image is used on the blanket cylinder, it is not possible to Let the press run while the image-bearing plate is on or the cassette in is removed from the image cylinder and replaced.

Stopping the press to replace an image-bearing plate or cassette acts as an interruption in printing that affects the entire printing process slowed down. In addition to the delays caused by changing the image-bearing plate or cassette, there is also the additional risk delays associated with restarting the press. This Delays are the result of the risk of the web breaking if the Printing is started again and the printing press at full speed starts. Starting and stopping the printing press to replace the image-bearing ones Plate or cassette increases the risk of a web break, which in turn leads to additional ones Delays can result when the web is fed back into the press must be removed and possible remnants of web must be removed from it.

The present invention relates to an apparatus and a method for making this possible the exchange of image-bearing plates or cassettes in an offset printing machine, without stopping the press. The present invention is eliminated hence the problems of conventional methods, the possible delays of the Printing process caused because the printing press for removal and Replacing the image-bearing plate or cassette must be stopped.

EP 0 321 360 A1 describes a tandem offset printing unit in which two Plate cylinder with a common blanket cylinder alternately in Active connection can be brought. For this, the two plate cylinders are on a swiveling frame, which allows one at a time of the two plate cylinders on the blanket cylinder and on an application roller a common inking unit of the two plate cylinders. The common inking unit of the two plate cylinders also has a single one Ink fountain unit on. The disclosed printing unit can be achieved by using two Plate cylinders can be used for flying printing plate changes.

EP 0 010 141 A1 also describes a device for producing Known printed products with changing impressions, which a common Has impression cylinder for two blanket cylinders. Each of the two A blanket cylinder is assigned to a respective plate cylinder, which one of them own inking and dampening unit as well as an ink fountain unit specific to it. The device corresponds to the principle of a satellite printing unit, in each case prints only one of the two printing units of the satellite printing unit on the material web, while the other printing unit is in the parked state and with a new one Pressure plate can be provided.

In the present invention, each blanket cylinder is at least two Image cylinders connected, each image cylinder an image-bearing plate or cassette includes. When one of the image cylinders engages ("in press") the blanket cylinder stands, whereby one image is transferred to the web for printing, is the other Image cylinder detached from the blanket cylinder ("out of print"). As a result, the other image cylinders are stopped, causing the image-bearing plate or cassette can be replaced without the entire operation of the printing machine being stopped must become. After changing the image-bearing plate or cassette on the stopped image cylinder can then be brought up to speed and with the Blanket cylinder in a relative angular orientation to ensure the Register accuracy can be engaged while the other image cylinder is disengaged so that thereafter a replacement of the image-bearing plate or Cassette of this image cylinder is possible.

According to the invention, the two image cylinders and a first and a second are for this purpose Ink roller mounted on a movable frame. This can be selective Inserting the first image cylinder ("in print") or the second image cylinder ("in Pressure ") with which at least one blanket cylinder is moved laterally (Change between positions "in pressure" and "out of pressure").

The present invention includes a drive and clutch assembly that Restart and register-accurate engagement of an image cylinder, which can be replaced the image bearing plate or cassette has been disengaged from the Blanket cylinder allows, while the other image cylinder, the Blanket cylinder and printing on the web was switched out of engagement brought and stopped.

Each image cylinder has its own paint application and moisture application device. According to the In the present invention, two image cylinders and ink application devices are combined on a frame for lateral movement relative to the blanket cylinder so attached that the lateral movement of one image cylinder and one Ink application device away from the blanket cylinder and out of engagement with it out a lateral movement of the other image cylinder and the other Ink application device on and in engagement with the blanket cylinder Consequence.

The present invention is more preferred in the following description Embodiments in connection with the attached, listed below Drawings explained in more detail.

Fig. 2A

eine Seitenansicht einer in vorliegender Erfindung verwendeten Hilfsantriebs- und Kupplungsanordnung, wobei sich die Kupplung in Hilfsantriebsposition befindet;

Fig. 2B

eine Seitenansicht der Hilfsantriebs- und Kupplungsanordnung gemäß Fig. 2A, wobei sich die Kupplung zwischen der Hilfsantriebsposition und der Hauptantriebsposition befindet;

Fig. 2C

eine Seitenansicht der Hilfsantriebs- und Kupplungsanordnung gemäß Fig. 2A, wobei sich die Kupplung in der Hauptantriebsposition befindet;

Fig. 3A-3B

ein Ausführungsbeispiel der vorliegenden Erfindung in der ersten bzw. zweiten Position;

Fig. 4

eine Seitenansicht der Hilfsantriebs- und Kupplungsanordnung gemäß Fig. 2A-2C;

Fig. 5

eine Seitenansicht einer Alternative der Hilfsantriebs- und Kupplungsanordnung gemäß Fig. 2A-2C.

Show it:

Figure 2A

a side view of an auxiliary drive and clutch assembly used in the present invention, wherein the clutch is in the auxiliary drive position;

Figure 2B

a side view of the auxiliary drive and clutch assembly of FIG 2A, with the clutch between the auxiliary drive position and the main drive position.

Figure 2C

a side view of the auxiliary drive and clutch assembly of FIG 2A, with the clutch is in the main drive position.

3A-3B

an embodiment of the present invention in the first and second position;

Fig. 4

a side view of the auxiliary drive and clutch assembly of FIGS 2A-2C.

Fig. 5

a side view of an alternative of the auxiliary drive and clutch arrangement according to FIGS. 2A-2C.

An embodiment of the device for switching the operation of the image cylinders P ₁ , P ₂ , P ₃ , P ₄ is shown in detail in FIGS. 2A-2C, 4 and 5. A blanket cylinder BLNKT comprises a shaft 1 which is attached to a blanket cylinder gear 2. In a manner known to the person skilled in the art, the rubber blanket cylinder transmission 2 is driven by known drive devices, which results in the rubber blanket cylinder transmission 2, the shaft 1 and the rubber blanket BLNKT being rotated. Blanket cylinder 2 is carried with a switchable image cylinder gear 3. Shaft 5 of the blanket cylinder BLNKT is connected to a blanket cylinder shaft encoder 13. The image cylinder gear 3 is mounted for rotation on a bearing 4, this bearing being fixed on a shaft 5 of the image cylinder P.

Also on shaft 5 is a coupling device 6, which moves along the length of shaft 5 and rotates with shaft 5. On one side, which faces the image cylinder P ₁ , the coupling device 6 comprises radially outwardly projecting wedges 7 which selectively engage in radially inwardly projecting wedges 8 on the inner circumference of the image cylinder gear 3 when the coupling device 6 is in the position shown in FIG. 2A position shown. The coupling device 6 further comprises, on a side facing away from the picture cylinder P _1, radially outwardly projecting wedges 9, into the radially inwardly projecting wedges 10 on the inner circumference of a first picture cylinder auxiliary drive pulley 11 when the coupling device 6 is shown in that in FIG. 2C Position. The first image cylinder auxiliary drive pulley 11 is mounted for rotation on a bearing 12, this bearing being fixed on the shaft 5 of the image cylinder P ₁ .

A belt or chain 14 is placed over the first image cylinder auxiliary drive pulley 11 entrained, this belt or chain 14 also via a second image cylinder auxiliary drive pulley 11 '(Fig. 4 and 5) and an auxiliary drive pulley 15 is carried. The auxiliary drive pulley 15 is driven by an auxiliary drive 16. In a Embodiment of the invention (FIG. 4), the belt or chain 14 drives a guide pulley 31 on, which is connected to the auxiliary coding device 17. In an alternative Embodiment (Fig. 5), the guide disc 31 is not used, and the auxiliary coding device 17 is connected directly to the auxiliary drive 16. In the alternative 5 can signals from the auxiliary encoder 17, the Reflect speed and phase angle, are processed to ensure that from the rotation of the auxiliary drive 16 derived signals speed and position the auxiliary drive disks 11, 11 'are reflecting.

Operation of the auxiliary drive and clutch assembly of the present invention will now be described with reference to Figures 2A-2C and Figures 4 and 5. 2A shows the present invention in a position in which the image cylinder P _{1 is} "in print" and is driven by the blanket cylinder BLNKT. In Fig. 2A it can be assumed that a second image cylinder P ₂ (not shown in Fig. 2A, shown in Figs. 4 and 5) is simultaneously "out of pressure" and is not driven by the blanket cylinder BLNKT, as above and below in described. In the position of the coupling device 6 shown in FIG. 2A, the wedges 7 and 8 engage in one another and thereby connect the shaft 5 to the image cylinder gear 3. As a result of this connection and the entrainment of the image cylinder gear 3 with the blanket cylinder gear 2, the image cylinder P ₁ becomes through and with the Blanket cylinder BLNKT driven. At the same time, the image cylinder P _{2 is} "out of print" and is not driven by the blanket cylinder BLNKT, ie a corresponding coupling device 6 connected to the image cylinder P ₂ is in the position shown in FIG. 2C, and the image cylinder P ₂ is slightly from the blanket cylinder BLNKT offset (ie "pivoted" by conventional pivoting devices to move an image cylinder for changing the plate on the image cylinder away from a blanket cylinder). In the position of the coupling device 6 shown in FIG. 2A, the shaft 5 is not coupled to the first image cylinder auxiliary drive pulley 11, which is why the auxiliary drive 16 has no influence on the image cylinder P ₁ .

If it is desired to bring the image cylinder P ₁ "out of pressure" and stop driving the image cylinder P ₁ with the blanket cylinder BLNKT in order to replace the image on this image cylinder, to replace the plate on or the cassette in the image cylinder in question or the inking roller For cleaning this cylinder, the image cylinder P _{2 is} brought up to speed with the blanket cylinder by operating the auxiliary drive 16 when the coupling device for the image cylinder P _{2 is} in the position shown in FIG. 2C. A control unit (not shown) compares the speed measured by the auxiliary coding device 17, which is connected either to the guide pulley 31 carried by the belt or chain 14 (FIG. 4) or directly to the auxiliary drive 16 (FIG. 5) and phase with the speed and phase measured by the blanket cylinder shaft encoder 13 and adjusts the speed of the auxiliary drive 16 so that a speed adjustment of the interlocking parts (wedges 7 and 8 or wedges 9 and 10) is achieved for engaging and disengaging. The auxiliary encoder 17 measures the speed of the auxiliary drive 16 and therefore the speed of the drive pulley 11, while the blanket cylinder shaft encoder 13 measures the speed of the blanket cylinder BLNKT and therefore of the transmission 3.

Register accuracy can be achieved in one of two ways. First, the angular position or phase angle of the auxiliary drive 16 can be adjusted to achieve register accuracy. This register accuracy is brought about by comparing the angular position measured by the auxiliary coding device 17 with the angular position measured by the coding device 13 of the blanket cylinder shaft, which rotates once per revolution of the blanket cylinder BLNKT, and adjusting the phase angle of the auxiliary drive 16 until register accuracy is achieved. Second, the wedges 7, 8 may include a guide member which allows a degree of relative rotation after engagement and which engages only in a specific angular position by guiding the wedges to this engagement. The wedges 7 and 8 are designed so that coupling is only possible in one position of the relative angles of rotation of the image cylinders P ₁ , P ₂ and the blanket cylinder BLNKT in order to ensure the image adjustment.

The coupling device 6 for the image cylinder P ₂ is then moved to the position shown in FIG. 2A, whereby a drive of the image cylinder P _{2 is} effected by the blanket cylinder gear ₂ . Next, the image cylinder P ₂ goes "in print". At the same time, the image cylinder P _{1 is} pivoted away from the blanket cylinder BLNKT, thereby "goes out of pressure", and the coupling device 6 for the image cylinder P ₁ is moved to the position shown in FIG. 2C. The auxiliary drive 16 is then slowed down until the rotation of the image cylinder P _{1 is} stopped. The plate on or the cassette in the image cylinder P ₁ can then be replaced and the inking unit for this image cylinder can then be cleaned. Alternatively, a cassette (not shown) can be contained in an image cylinder P ₁ and actuated to position a virgin layer of an imageable material or a pre-imaged layer on the periphery of the image cylinder P ₁ . In this embodiment, the cassette only needs to be replaced when all of the material in the cassette has been used up. After a cassette has been replaced, the auxiliary drive 16 can be used to drive the image cylinder P ₁ while it is being imaged by an imaging device I. If it is desired that printing is then started with image cylinder P ₁ and ended with image cylinder P ₂ , the method described above can of course be reversed.

3A and 3B show an embodiment of the present invention. By doing 3 is a blanket cylinder blanket in engagement with a web W. Above the blanket cylinder BLANKET is a side Slidable frame 23 on which a first inking and imaging device 21 and a second inking and imaging device 22 are attached. The inking unit Imaging devices 21, 22 each comprise their own inking roller (D, F, J, K, L) and its own plate cylinder. Is fixed over the frame 23 a common ink fountain unit 20. FIG. 3A shows a first position of the frame 23, and Fig. 3B shows a second position of the frame 23. In the first position of the Frame 23 connects the first inking and imaging device 21 Ink fountain unit 20 with the blanket cylinder BLANKET, while the second Inking unit and imaging device 22 of the ink fountain unit 20 and the Blanket cylinder BLANKET is separated. According to the first position of the frame 23 Fig. 3A can the image-bearing plate or cassette on the second inking and Imaging device 22 are replaced, and the second inking and Imaging device 22 can be cleaned. In the second position of the frame 23 connects the second inking and imaging device 22 to the ink fountain unit 20 with the blanket cylinder BLANKET, while the first inking and Imaging device 21 of the ink fountain unit 20 and the blanket cylinder BLANKET is separated. In the second position of the frame 23 according to FIG. 3B, the Image-bearing plate on or cassette in the first inking and imaging device 21 can be replaced, and the first inking and imaging device 21 can getting cleaned.

LIST OF REFERENCES

BLNKT

Blanket cylinder

P ₁ , P ₂

image cylinder

D, F, J, K, L

Rolling the ink roller

M, N, P

Rolling the dampening roller train

Plate

Plate cylinder / image cylinder

Blanket

Blanket cylinder

S

Sprühauftragwalze

A

Ink fountain rollers

B

ink metering

W

train

1

wave

2

Blanket cylinder gear

3

Image cylinder gear

4

camp

5

wave

6

coupling device

7

wedges

8th

wedges

9

wedges

10

wedges

11

Image cylinder auxiliary drive pulley

11 '

second image cylinder auxiliary drive pulley

12

camp

13

Blanket cylinder shaft encoder

14

Strap or chain

15

Auxiliary drive pulley

16

auxiliary drive

17

Auxiliary encoder

20

Ink fountain unit

21

first inking and imaging device

22

second inking and imaging device

23

frame

31

idler

Claims (18)

1. An apparatus for changing images during operation of a printing press, whereby the apparatus comprises at least one blanket cylinder (Blanket, BLNKT), at least one ink fountain unit (20), a first image cylinder (Plate, P₁) and a second image cylinder (Plate, P₂), which can be selectively engageable with the at least one blanket cylinder, whereby the first image cylinder (Plate, P₁) may be disengaged from the at least one blanket cylinder (Blanket, BLNKT) when the second image cylinder (Plate, P₂) is engaged with the at least one blanket cylinder (Blanket, BLNKT), and whereby the second image cylinder (Plate, P₂) may be disengaged from the at least one blanket cylinder (Blanket, BLNKT) when the first image cylinder (Plate, P₁) is engaged with the at least one blanket cylinder (Blanket, BLNKT),
   characterized in
   a movable frame (23), whereby the first image cylinder (Plate, P₁) and second image cylinder (Plate, P₂), a first ink train (21) and a second ink train (22) are mounted on the movable frame (23) and whereby the movable frame (23) can be laterally shifted for selectively engaging the first image cylinder (Plate, P₁) or the second image cylinder (Plate, P2) with the at least one blanket cylinder (Blanket, BLNKT).
2. The apparatus according to claim 1,
   characterized in that the movable frame (23) can be moved from a first position, where the image cylinder (Plate, P₁) is engaged with the at least one blanket cylinder (Blanket, BLNKT), to a second position, where the second image cylinder (Plate, P₃) is engaged with the at least one blanket cylinder.
3. The apparatus according to claim 2,
   characterized in that in the first position of the movable frame (23), the ink fountain unit (20) supplies ink to the first image cylinder (Plate, P₁), and in the second position of the movable frame (23), the ink fountain unit (20) supplies ink to the second image cylinder (Plate, P₃).
4. The apparatus according to claims 1, 2, or 3,
   which further comprises a second ink fountain unit (20), whereby the at least one ink fountain unit (20) supplies ink to the first image cylinder (Plate, P₁) and the second ink fountain unit (20) supplies ink to the second image cylinder (Plate, P₃).
5. The apparatus according to one of the preceding claims, which is further connected with the at least one blanket cylinder (Blanket, BLNKT), a first image cylinder gear (3) selectively connectable to the first image cylinder (Plate, P₁), and a second image cylinder gear (3) selectively connectable to the second image cylinder (Plate, P₃), the first image cylinder gear (3) and the second image cylinder gear being entrained with the image blanket cylinder gear (2), a first clutch (6) selectively coupling the first image cylinder gear (3) to the first image cylinder (Plate, P₁), and a second clutch selectively coupling the second image cylinder gear to the second image cylinder (Plate, P₃).
6. The apparatus according to claim 5,
   characterized in that the first clutch (3) and the second clutch comprise mating splines (7, 8, 9, 10).
7. The apparatus according to claim 6,
   characterized in that the mating splines (7, 8, 9, 10) comprise a piloting element.
8. The apparatus according to claim 5, which further comprises a first auxiliary image pulley (11) selectively connected to the first image cylinder (Plate, P₁), the first clutch (6) selectively coupling the first auxiliary image pulley (11) to the first image cylinder (Plate, P₁), and a second auxiliary image pulley (11') selectively connected to the second image cylinder (Plate, P₃), the second clutch selectively coupling the second auxiliary image pulley (11') to the second image cylinder (Plate, P₃).
9. The apparatus according to claim 8, which further comprises an auxiliary drive (16), the auxiliary drive (16) driving the first and second auxiliary image pulleys (11, 11').
10. The apparatus according to claim 9, which further comprises a belt (14) or a chain (14), the belt (14) or chain (14) being connected between the auxiliary drive (16) and the first and second image cylinder gears.
11. The apparatus according to claim 8, which further comprises an auxiliary encoder (17), the auxiliary encoder (17) measuring the speed and position of the first auxiliary image cylinder pulley (11) and the second auxiliary image cylinder pulley (11').
12. The apparatus according to claim 10, which further comprises an auxiliary encoder (17), the auxiliary encoder (17) measuring the speed and position of the first auxiliary image cylinder pulley and the second auxiliary image cylinder pulley (11'), and further comprising an idler pulley (31) entrained with the belt (14) or chain (14), the auxiliary encoder (17) being connected to the idler pulley (31).
13. The apparatus according to claim 9, which further comprises an auxiliary encoder (17), the auxiliary encoder (17) measuring the speed and position of the first auxiliary image cylinder pulley (11) and the second auxiliary image cylinder pulley (11'), wherein the auxiliary encoder (17) is connected to the auxiliary drive (16).
14. A method for changing images during the operation of a printing press, comprising the following steps:

    providing at least one blanket cylinder (Blanket, BLNKT), providing at least one ink fountain unit (20);

    providing a first image cylinder (Plate, P₁) and a second image cylinder (Plate, P₂), the first image cylinder (Plate, P₁) and

    the second image cylinder (Plate, P₂) being selectively engageable with the at least one blanket cylinder (Blanket, BLNKT),

    disengaging the first image cylinder (Plate, P₁) from the at least one blanket cylinder (Blanket, BLNKT) when the second image cylinder (Plate, P₂) is engaged with the at least one blanket cylinder (Blanket, BLNKT)

    characterized in

    mounting the first image cylinder (Plate, P₁) and the second image cylinder (Plate, P₂) on a movable frame;

    mounting a first ink train (21) and a second ink train (22) to the movable frame (23);

    laterally shifting the movable frame (23) for selectively engaging the first image cylinder (Plate, P₁) or the second image cylinder (Plate, P₂) with the at least one blanket cylinder (Blanket, BLNKT).
15. The method according to claim 14, which further comprises the following steps:

    moving the movable frame (23) from a first position where the first image cylinder (Plate, P₁) is engaged with the at least one blanket cylinder (Blanket, BLNKT), to a second position, where the second image cylinder (Plate, P₃) is engaged with the at least one blanket cylinder (Blanket, BLNKT).
16. The method according to claim 15, which further comprises the following steps:

    connecting the ink fountain unit (20) to the first image cylinder (Plate, P₁) in the first position of the movable frame (23), and connecting the ink fountain unit (20) to the second image cylinder (Plate, P₃) in the second position of the movable frame (23).
17. The method according to claim 14, which further comprises the following steps:

    providing a second ink fountain unit (20), and supplying ink to the first image cylinder (Plate, P₁) using the at least one ink fountain unit and (20), and supplying ink to the second image cylinder (Plate, P₃) using the second ink fountain unit (20) .
18. An offset printing press, especially a rotary printing press,
    characterized in
    an apparatus according to one of claims 1 to 13.

Images