EP0131110B1 - Inking device for letter press and offset printing machines - Google Patents

Abstract

The invention relates to an inking mechanism for letterpress and offset printing machines comprising a vibrator having a plurality of discs which are disposed side by side and which are adapted to reciprocate individually and independently of one another between a duct roller and a transfer roller, and the width of each of which corresponds to a specific inking zone. The disc each consist of a middle part and an outer ring with a covering and are disposed side by side without gaps on a stationary carrier tube. Each middle part is mounted movably on the carrier tubes and has a circular outer periphery on which the outer ring is rotatably mounted and a drive for the individual movement of the middle part is provided inside each disc.

Description

Ink metering device for book and offset printing presses consisting of an ink fountain, an ink fountain roller, a squeegee and an ink fountain, the ink lifter consists of disks arranged side by side, which oscillate individually and independently of each other between the ink fountain roller and a transfer roller and the width of which corresponds to a certain ink zone.

In order to be able to achieve good ink transfer for a given print job, a wide variety of solutions in the form of split lifter rollers have become known.

For example, CH-PS 169 362 shows an inking unit for rotary printing presses with a plurality of individually adjustable and detachable lifter rollers arranged on a common shaft, the lengths of which correspond to the width of a printing plate. For each lifting roller, a control disk with several cams of different sizes lying next to one another is arranged on a common shaft so as to be longitudinally displaceable and adjustable.

With this device it should be possible to be able to regulate the coloring of each individual page in relation to the color strip position during operation from a central point.

DD-PS 104 259 is intended to solve the problem of being able to program predetermined and / or calculated dosed amounts of ink in a programmed manner, and to be able to eliminate inking disturbances during production by means of control technology with machine-technical requirements.

This is to be achieved by means of a device for zoneless screw and ink knife-free ink metering on printing presses in offset printing and letterpress printing. In order to achieve a predetermined uniform coloration on the printing sheet when printing solid areas, an ink layer thickness required for each ink-paper combination used is provided by finely adjusting a roller gap between the ductor and a counter roller and / or by a speed difference between these two rollers. The zone slides are only guided on one side.

In DE-OS 2 924 635 the object is to be achieved with a color metering device in book and offset printing presses, which should consist of a low susceptibility to faults against paper components and fountain solution and which should enable a color requirement of the printing form to be provided with a corresponding ink supply.

This is to be achieved by an ink metering device which consists of an ink fountain with ink knife and an ink fountain roller with ink lifter for electronic ink zone remote controls for book and offset printing presses and in which several ink lifter wheels are provided which oscillate individually and independently of one another and their width in each case a specific ink zone corresponds.

All of the above-mentioned devices divide the lifter roller into a plurality of transfer rollers which are arranged next to one another in the manner of disks and which each have to be held laterally for driving. This means a large gap between the individual ink transfer rollers when the ink transfer rollers are held on both sides. Nevertheless, the stability of the bracket is not sufficient with the size of the lever arm to be able to absorb the forces when transferring the ink from the box roller to the grater. A lateral deflection while touching the ink lifter discs on the grater is therefore not inevitable with the narrow mounting plates, since this deflection occurs during each contact with the grater, there is a risk of the mounting plate breaking permanently. No concrete statements have been made about the control of the paint regulator disc wheels.

Proceeding from this prior art, the object of the invention is to create a compact and stable, zone-by-zone ink transfer which is easily adjustable and can be easily installed in the printing press by the printer.

The solution of the problem is achieved in a color metering device of the type mentioned above by the features of the characterizing part of claim 1.

The discs consist of a central part and an outer ring with a coating and are arranged side by side without a gap on a stationary support tube. No color can thus settle between the individual disks during the printing process, which later has to be removed in complex cleaning processes.

The cylindrical outer ring with cover is attached to the middle part and can be freely rotated. Depending on the design of the disc, the outer ring runs on a roller bearing, or if the middle part consists of a compact plastic or plain bearing material, on this plastic, e.g. Turcite. The freely rotatable outer rim enables the peripheral speed to be immediately adapted to the peripheral speed of adjacent rollers.

The middle part is movably mounted on a support tube. Different types of movement are possible. On the one hand, the middle part can be mounted eccentrically on the round support tube, or oscillates or oscillates around the round support tube, or it performs a linear movement on the square support tube.

A drive for adjusting the central part is provided within each slide. The drive can be an electrical coil with a magnetic core, in which the middle part is magnetically attracted, or a rectified electromagnet, if the middle part is formed from a plastic. The drive in a pneumatic version consists of a piston with a return spring inside a cylinder in the middle of the carrier tube. Pen the middle part delt here around the support tube and is suspended from this in the middle and positively guided on its underside on a plain bearing.

Another option provides a stepper motor for targeted control of the disk. The inner ring of the stepper motor is shrunk onto the central cylindrical carrier shaft, the outer ring of the stepper motor is inserted into the eccentric movable part of the slide. The connection for the electrical control of the individual disks is via a common plug-in device, so that the fixed central axis, that is, the support tube, makes it easy and quick to install and remove for a wide variety of purposes. The entire unit can be easily removed from the printer without an installer, since the entire transfer rollers are arranged compactly on the carrier tube. This leads to a significant reduction in set-up times, since the entire zonal presetting of the color knife is no longer necessary.

All disks can be washed with the existing washing device as with a normal conventional lifter, which leads to a further significant reduction in makeready time on the printing press. A special control circuit allows the disks on the carrier tube to be placed on the same level, so that they work as a whole as a conventional, known lifter.

With the electrical control it is also possible to control the angle of rotation of the individual ink transfer rollers and the stop time on the box roller and to check the amount of ink strips in the ink control system. This sensing unit is built into each individual pane and allows the smallest angle differences here e.g. Compensate for errors or differences in the transmitted film length. This scanning takes place over several cylinder revolutions, so that only one evaluation unit is required for "n" disks.

The accuracy or sensitivity of the color metering device is significantly increased, so that the different color strips can be specifically controlled at different stroke frequencies.

E.g. an angular step encoder, which runs synchronously with the printing form carrier coupled with a simple computer, allows this to counteract color fluctuations that occur in a color zone. The computer must be programmed with the behavior data of the inking unit. By controlling the point of use of the corresponding ink transfer rollers or regulating their stroke frequency and changing the color stripe to be transported, a zone-by-zone different color profile can be generated not only axially but also radially on the printing form. Given the high accuracy of the color metering device, detection of the color temperature by indirect measurement of the temperature via the disks is provided. The regulation of the pre-metering mechanisms and the ink transfer roller rotation angle on the ink fountain roller is derived from these values. This eliminates manufacturing inaccuracies, assembly quantities, storage inaccuracies, wear and temperature influences. In a particularly advantageous manner, this means a device which is much cheaper and more robust. Another reduction in price is the greater tolerance training of the individual finished parts.

Furthermore, the ink zone division can be carried out much smaller than the previous division, since the zone division now customary in offset printing results from the flexibility of the ink knife, i.e. Due to the high spring stiffness of the color knife, it is practically impossible to select smaller delivery zones when viewed in the axial direction, although this would allow the printer to adjust its color profile more specifically to the image to be printed. The wear on the disks and on the ink fountain roller is almost zero compared to the known metering elements, since there is no friction. As mentioned above, this is a great advantage on the temperature influences of the work process, because the temperature remains essentially constant over longer periods. As mentioned above, the closely spaced panes do not form any gaps in the color transfer. The ink transfer is thus optimally uniform across the entire machine width. This means that the rubbing can be carried out minimally, or the rubbing to level the color in the area of the color transfer is completely dispensed with, since the rubbing on the plate is sufficient for the optimal color transfer.

Another advantage of the particularly uniform ink transfer is that there is no need to destroy the cleavage, ie the ink that runs back in the roller train after the application. This makes it possible to provide a short inking unit on the printing press for certain requirements.

In a further embodiment, a holding magnet can be articulated in the carrier tube with a lever transmission in order to achieve greater disc heights with a small stroke of the drive.

Further advantages and essential features of the invention emerge from the subclaims and the following description of the figures of the exemplary embodiments.

• Fig. 1 eine Übersichtszeichnung der einzelnen zonalen Scheiben auf einem Trägerrohr zwischen einer Kasten- und Übertragwalze in perspektivischer Darstellung,
• Fig. 2 eine Scheibe die auf einem quadratischen Trägerrohr und einem Mittelteil aus Kunststoff geradlinig mittels Elektromagnet bewegbar ist,
• Fig. 3 eine pneumatisch mit einem Kolben und Rückholfeder um einen oberen Aufhängepunkt schwenkbare Scheibe,
• Fig. 4 eine Schnittdarstellung durch mehrere exzentrisch gelagerte Scheiben die mit einem Schrittschaltmotor auf einem runden Trägerrohr gelagert sind,
• Fig. 5 eine exzentrisch gelagerte Scheibe mit einem Gleitlager im Trägerrohr und einem Rollenlager unter dem Außenkranz mit Überzug,
• Fig. 6 Scheiben, bei denen mit einem Haftmagnet und einer Hebelübertragung die Hubbewegung erzeugt wird.

It shows:

• 1 is an overview drawing of the individual zonal slices on a support tube between a box and transfer roller in a perspective view,
• 2 shows a disk which can be moved in a straight line by means of an electromagnet on a square support tube and a central part made of plastic,
• 3 shows a disc which can be swiveled pneumatically with a piston and return spring about an upper suspension point,
• Fig. 4 is a sectional view through several eccentrically mounted discs with one Stepper motor are mounted on a round support tube,
• 5 is an eccentrically mounted disc with a slide bearing in the support tube and a roller bearing under the outer ring with a cover,
• Fig. 6 discs in which the lifting movement is generated with a holding magnet and a lever transmission.

1 shows a box roller 1 and a transfer roller 1.1 of an ink metering device for book and offset printing machines, between which individual disks 3 are movably arranged on a carrier tube 7 for zonal ink transfer. The disks 3 lie closely next to one another and transfer the ink without empty gaps from the box roller 1 with a well reproducible control to the transfer roller 1.1.

The control of the disks 3 in the form of electrical signal processing is digitized and related to the machine speed. Different designs on different carrier tubes are possible as drives for the disks, depending on the intended use.

The carrier tube 7 with the disks 3 can be installed and removed by the printer without significant expenditure of time.

FIG. 2 shows a disk 2 which is mounted so that it can move in a straight line on a square support tube 7. The disc 2 has a cylindrical outer ring 11 with a coating 12, which receives the color depending on the investment time on the box roller 1. Around the support tube 7 is a central part 14, which is made of a self-lubricating sliding material e.g. Turcite is arranged. For this purpose, the central part 14 has a right-angled recess 38, which is made larger on one side by a stroke width 39 than the carrier tube 7.

Thus, the central part 14 can execute the stroke width 39 in a straight line on the carrier tube 7 if the corresponding impulse is exerted on the disk 2 by a drive 19. The drive 19 is an electromagnet 32, which transmits the lifting movement via a plunger 33 to a cross bar 34, which in turn is anchored in the central part 14. The resetting of the stroke width 39 takes place via springs 37. In each middle part 14 of the disk 2, a lubrication and air ring line 35, 36 is arranged around the support tube 7, in such a way that the middle parts can move past one another in a slightly sliding manner. The lubrication and air ring line 35, 36 consists of a circular half-sided recess on each side of the central part 14, the semi-circular recesses being connected to one another by four transverse bores which lead through the central part 14.

FIG. 3 shows a disk 3 which is arranged on a cylindrical support tube 8 and can be moved back and forth by the drive 20 so as to oscillate about the support tube 8. The disc 3 consists of a cover, an outer ring 11 located underneath, which is arranged on a roller bearing 31 so that it can rotate easily on a central part 15. The middle part 15 in turn is arranged centrally on a guide roller 29 on the support tube 8. The carrier tube 8 is flattened on its underside and the middle part 15 is slidably guided by a sliding roller 29.1 during a pendulum movement. The pendulum movements are generated by a pneumatic reciprocating piston 28 which transmits its movements to a piston tappet 30, the piston tappet 30 acting on the central part 15 through a bore in the carrier tube 8. The pendulum movement is reset via a spring 28.1 and a plunger 30.1 which is exactly as the reciprocating piston 28 is guided in the drive 20 in the carrier tube 8. The pneumatic controls of the drive 20 are laid in the cavity of the support tube 8. The exhaust air from the pneumatic drive is used as a forced ventilation of the cavity in the carrier pipe in order to be able to dissipate any heat.

Similar forced ventilation is provided in the other exemplary embodiments for heat dissipation, this is a particularly favorable equalization of the temperature within the paint metering device.

4 several disks 4 are shown lying side by side in section on a support tube 9. The disks 4 show different contact positions according to their respective rotational positions by means of a drive 21. The disks 4, like all other disks, have the coating 12 and the cylindrical outer ring 11. The cylindrical outer ring 11 runs on an eccentric central part 16, so that the actuating movements of the drive 21 for ink transfer between the box roller 1, not shown, and the transfer roller 1.1 is possible. The drive 21 is a stepping motor, which is composed of an inner ring 40 and an outer ring 41. The inner ring 40 is shrunk onto the carrier tube 9, the outer ring 41 is fastened in the eccentric central part 16. The discs 4 are fixed on the support tube 9 by a side bracket 42. The side bracket 42 is also the connection for the lubrication and air ring line 35, 36 which go between the individual disks and through the adjacent disks 4.

FIG. 5 shows a disk 5 consisting of the cover 12 and the cylindrical outer ring 11 which, as already shown in FIG. 3, is rotatably mounted on a roller bearing 31 on a central part 17. The middle part 17 is mounted eccentrically on a support tube 10. A slide bearing 26 is arranged between the round support tube 10 and the eccentrically mounted central part 17. The middle part 17 additionally has a free space 27 in which a drive 22 is arranged. The drive 22 consists of a coil 24 and a magnetic core 25. The disc 5 has a seal 5.1 on one side. The seal 5.1 prevents the penetration of paint and at the same time promotes the free movement of the panes among themselves.

FIG. 6 shows a sectional view through two disks 6 which are mounted on a square support tube 7 similar to FIG. 2. The discs 6 again consist of the cover 12 and the cylindrical outer ring 11 which is slidably mounted here on a middle part 18, since the middle part 18 is made of a sliding material e.g. Turcite exists. The middle part 18 executes a linear movement on the carrier tube 7. The stroke width 39 is the max. rectilinear movement of the middle parts 18 or the disks 6 on the carrier tube 7. The movement of the disks 6 are generated by an electric drive 23. The drive 23 is in this case a holding magnet 43 fastened on one side within the carrier tube 7. The holding magnet 43 is enclosed and guided by an outer sleeve 43.1. The minimum stroke movement of the holding magnet 43 is transferred to a roller 47 via a lever 44 which passes through a slot 45 in the carrier tube and is simultaneously articulated on the inside of the carrier tube 7. The roller 47 is guided in a guide 46 of the middle part 18 of the disks 6. The minimum stroke movement of the holding magnet 43 can thus be increased to the stroke width 39 via the lever 44.

Reference symbol list

• 1 box roller
• 1.1 transfer roller
• 2 disc
• 3 _"
• 4 _"
• 5 _"
• 6 _"
• 7 support tube
• 8th
• 8th
• 9
• 10th
• 11 outer wreath
• 12 coating
• 13
• 14 middle section
• 15 _"
• 16
• 17th
• 18th
• 19 drive
• 20th
• 21st
• 22
• 23
• 24 coil
• 25 magnetic core
• 26 plain bearings
• 27 Freezer room
• 28 reciprocating pistons
• 28.1 spring
• 29 Leadership role
• 29.1 Roller
• 30 piston tappets
• 30.1
• 31 roller bearings
• 32 electromagnets
• 33 plungers
• 34 crossbar
• 35 lubrication-36 air ring line
• 37 springs
• 38 recess
• 39 stroke width
• 40 inner ring
• 41 outer ring
• 42 side bracket
• 43 holding magnet
• 43.1 outer shell
• 44 levers
• 45 slot
• 46 leadership
• 47 roll

Claims (10)

1. Ink metering device for letterpress and offset printing presses with an ink vibrator which consists of discs (2-6) arranged adjacent one another which are movable individually and independently to one another between an ink fountain roller (1) and a transfer roller (11) and the width of which in each cae corresponds to a given ink zone, characterised in that the discs (2-6) consist in each case of a centre part (14-18) and an outer ring (11) with a cover (12) and are arranged practically without gaps lying adjacent one another on an inner lying stationary carrier tube (7-10), that the centre part (14-18) is mounted radially movably but axially fixedly on the carrier tube (7-10), that the middle part (14-18) has a circular exterior periphery, on which the outer ring (11) is rotatably mounted and that within each disc (2-6) a drive (19-23) is provided for adjustment of the middle part (14-18).

2. Ink metering device according to Claim 1, characterised in that on the carrier rube (10) an eccentrically bored out middle part (17) is movably mounted via a sliding bearing (26) and that the middle part (17) has a free space (27) in the region of the drive (19-23) of ca. 1/3 of a revolution.

3. Ink metering device according to Claim 1 or 2, characterised in that on the round carrier tube (10) corresponding to the width of each disc (5) there is arranged in each case a coil (24) with a magnetic core (25), that a sliding bearing (26) is fixed around the carrier tube (10) over a pivotal range of the disc (5) and that on one side of each disc (5) there is fixed a seal (5.1).

4. Ink metering device according to Claim 1, characterised in that in the round carrier tube (8) is arranged a one side sprung piston (28), that the carrier tube (8) is flattened on its underside in the swinging region, that on its upper side at the carrier tube (8) the round centre portion (15) of the disc (31) is borne on a guide roll (29) and on the underside is guided by a sliding roll (29.1), that piston rods (30, 30.1) bear on both sides via the carrier tube (8) on the centre portion (15) and that the cylindrical outer ring (11) is mounted on a roller bearing (31).

5. Ink metering device according to Claim 1, characterised in that in the quadrangular carrier tube (7) electromagnets (32) are arranged mounted, that a push rod (33) of the electromagnet (32) is fixed to a transverse bar (34) which is arranged within the centre part (14) guided in a straight line on the carrier tube (7), and that the cylindrical outer ring (11) is slidably mounted on the centre part (14).

6. Ink metering device according to Claim 1 and 5, characterised in that between the centre parts (14, 16) there is arranged a connected together lubrication (35) or air circuit connection (36) which can be connected to a side holder (42) for the discs (21) fixed to the carrier tube (7, 9).

7. Ink metering device according to Claim 1, 5 and 6, characterised in that the centre part (14) is constructed of a sliding bearing material and that a rectangular aperture (38) of the centre part (14) in the straight line direction of movement of the disc (2) is cut out larger in terms of the stroke width (39) than the carrier rube (7) in its exterior dimension.

8. Ink metering device according to Claim 1, characterised in that the drive (21) of the disc (4) is a switched stepping motor of an inner ring (40) shrunk onto the carrier tube (9) and an outer ring (41) shrunk onto the eccentric centre portion (16).

9. Ink metering device according to Claim 1, characterised in that the drive (23) is an engaging magnet (43) on one side of which a lever (44) pivoted to the carrier tube (7) is fixed and that the lever (44) is arranged with its free end movably guided on the centre part (18) through a slot (45) of the carrier tube (7).

10. Ink metering device according to at least one of the preceding Claims, characterised in that the discs (2-6) have a measuring device for noting the rotational angle and that the carrier tubes (7-10) can be force ventilated.

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