EP1570986A2 - Method for controlling the pressing force of an adjustable mounted roll - Google Patents

Abstract

Device for adjusting the pressing pressure between an adjustable first roller (21) and a second roller (22) and/or for adjusting the first roller on the second roller in a printing machine comprises an actuator (34) impinged by a pressure which presses the first roller with an adjustable force in the direction of the second roller. The pressure of the pressure medium can be adjusted using a valve. A switching unit is provided by which the valve is connected to the actuator. An independent claim is also included for a process for adjusting the pressing pressure between an adjustable first roller and a second roller and/or for adjusting the first roller on the second roller in a printing machine. Preferred Features: Two valves are provided to adjust the pressure of actuator. The valves are connected to the actuator of the rollers by switching the switching unit. The valves are formed as flow regulating valves.

Description

The invention relates to a method for adjusting the contact pressure of an adjustable mounted roller according to the preamble of claim 1.

In conventional printing machines, such as web-fed rotary printing presses, There are a variety of rollers available. In particular, ink rollers are provided, the serve the transfer of color from a color memory on the plate cylinder. By the inking rollers can be dosed the color transferred to the plate cylinders, so that the color is transmitted as a uniform film of a certain thickness. Faults, like for example, speed variations and torsional vibrations can thereby be compensated.

In addition, dampening rollers can be provided in the printing press, the a dampening solution, such as water, transferred to the printing unit.

Frequently, pairs of rollers are formed by mutually engaging rollers at where at least one of the rollers has a cylindrical surface of elastic material, so that this cylindrical surface depends on the contact pressure of the opposite roller at least slightly deformed. The result is given by the elastic Deformation of the roll surface extending straight between the rolls Contact area, referred to as a contact strip. The width of the contact strip can be varied by creating the contact pressure between the rollers, the width of the contract strip has a significant influence on the print result Has. For example, if the contact strip is too narrow in an inking unit, it will not enough color transfer, whereas in cases where the contact strip too wide is, the elastic roller can be damaged by the occurring flexing work.

In particular, the strip width depending on the operating conditions, for example, the temperature of the printing machines or their Wear level, to always be able to adjust correctly, it is necessary to use the one roller to be stored in an adjustable position so that they are provided with an actuator with an adjustable force in the direction the opposite roller can be pressed. Is then the right contact pressure found between the two rollers, a fixing device for fixing the pressed first roller relative to the second roller to sustain the contact pressure permanently to obtain.

From DE 197 19 305 A1 is a device for adjusting the contact pressure known between two rollers. In the bearing assembly described there is the Adjustable mounted roller with a spring, located on the frame of the printing press supported, pressed against the opposite roller. As a result, depends on the selected spring characteristic always a certain contact pressure between the two rolls off. To fix the roller in the pressed position is a Clamping mechanism with clamping lever and clamping plate described by the Roll axis can be fixed by friction on the frame of the printing press.

From DE 199 19 733 A1 a device for semi-automatic adjustment of Rollers known in which the adjustably mounted roller held in a roll holder is, which in turn is mounted on a frame-mounted frame holder. Roller holder and frame holder can be moved against each other and are interconnected by elastic means. The elastic means have a certain bias, so that adjustable on the roll holder mounted roller with a certain contact pressure against the opposite Roller can be pressed. To lock the roller holder on the frame holder are Locking bolt provided by the delivery of the roll holder frictionally on Frame holder can be jammed.

DE 38 08 142 A1 describes a device for supporting two cylinders. Here is the contact pressure between two on and off rolls by changing the Pressure of the print medium changeable. Also, a switching device is arranged with which the pressure medium can be guided optionally to different actuators.

DE-OS 16 11 303 discloses a device for turning on and off a Printing cylinder of a gravure printing machine, wherein a pressure reducing valve is provided.

By the US 2,774,301 A and GB 12 13 935 A ink rollers are known by means of pressure-actuable actuators are adjustable. Here is a valve for adjusting the Height of the pressure and at least one shut-off valve provided.

The invention has for its object to provide a method for adjusting the To create contact pressure of an adjustably mounted roller.

The object is achieved by the features of claim 1.

In the devices, the actuator for adjusting the contact pressure in the manner of with a pressurized medium, a biased gas, in particular compressed air acted upon Pressure body formed. To adjust the pressure of the print media to the To be able to change the contact pressure, valves are provided. Because of a wet or Inking a variety of adjustable rollers are provided, would be one of the number the actuators corresponding number of valves normally necessary, giving a meant high equipment expense. This high effort is thereby avoided that a switching device is provided with the control valves optionally connectable to different actuators. This means with others Words that the adjustable rollers are then not all set at the same time can, but only the actuators are actuated, via the switching device connected to the adjusting valves. Depending on the design of the color or However, dampening units are only enough to set the entire inking or dampening system Valves with which successively the contact pressure of the various adjustable Rolling is adjusted.

According to a preferred embodiment, only two valves are provided with which then simultaneously the pressure of two actuators on an adjustable roller is adjustable. To adjust the various adjustable rollers then so Proceeded that in each case an adjustable roller by actuation of the two valves is adjusted and after the adjustment by pressing the fixing the Setting is fixed. After fixation can then with the setting of the next adjustable roller to be continued.

After the process, the angular position of the second roller on which the first roller with adjustable contact pressure is pressed, recorded. By controlling this angular position is it is possible that the pressing or adjusting the adjustable roller then only in certain angular positions of the second roller is performed.

This type of control of the pressure is particularly important in the form of cylinders, at the periphery of fastening means for fixing the printing plates are provided. Namely, the setting or employment of adjustable rollers in a straight Angular position made at which the adjustable roller on the fastening device of the forme cylinder comes to rest, the set values by the changed diameter in the field of fastening device falsified. These Falsification can be excluded by controlling the angular position of the second roller become.

According to another preferred embodiment, the setting of the Contact pressure and / or the employment of the first roller to the second roller at simultaneous rotation of the rolls.

Embodiments of the invention are illustrated in the drawings and are in described in more detail below.

Fig. 1

eine schematisch dargestellte Vorrichtung zum Einstellen des Anpressdrucks zwischen zwei Walzen im Längsschnitt;

Fig. 2

die schematisch im Querschnitt dargestellte Vorrichtung gemäß Fig. 1 in einer Grundstellung;

Fig. 3

die schematisch im Querschnitt dargestellte Vorrichtung gemäß Fig. 1 in einer ausgelenkten Stellung;

Fig. 4

die Vorrichtung gemäß Fig. 1 in einer perspektivischen Ansicht von vorne;

Fig. 5

ein zweites Ausführungsbeispiel eines Aktors für eine Vorrichtung im Querschnitt;

Fig. 6

ein Farbwerk mit mehreren einstellbaren Walzen zur Anstellung an einem Formzylinder;

Fig. 7

eine Umschalteinrichtung zur wahlweisen Umschaltung zweier Ventile zwischen verschiedenen Aktoren.

Show it:

Fig. 1

a schematically illustrated device for adjusting the contact pressure between two rollers in longitudinal section;

Fig. 2

the device shown schematically in cross-section according to Figure 1 in a basic position.

Fig. 3

the device shown schematically in cross-section of Figure 1 in a deflected position.

Fig. 4

the device of Figure 1 in a perspective view from the front.

Fig. 5

a second embodiment of an actuator for a device in cross section;

Fig. 6

an inking unit with several adjustable rollers for employment on a forme cylinder;

Fig. 7

a switching device for selectively switching two valves between different actuators.

In Fig. 1 is a device 20 for adjusting the contact pressure between a first Roller 21 and a second roller 22 are shown. The roller 21 can with the ends of their Axis 23 or pin releasably provided on a device 20 on the Quick release fastened 24. Such quick fasteners are out of the art known in the art and have a semicircular bearing shell, in which the ends the axis 23 can be inserted. By attaching a in Fig. 1 not shown upper bearing shell can then the axis 23 on the quick release 24th be determined.

The device 20 is essentially composed of a frame holder 26 and a Roll holder 27 constructed, the relative to each other in a plane that is perpendicular extends to the drawing plane, can be moved against each other. Of the Frame holder 26 is made of a base plate 28, for example by means of a Swivel arm can be pivotally attached to the frame of a printing press, and a sleeve body 29 constructed. On the side facing the roller 21 has the Sleeve body 29 a recess 31 into which a cylindrical portion 32 of the Roller holder 27 engages. The inner diameter of the recess 31 and the outer diameter of the section 32 is chosen so that a in the Basic position circular cylindrical gap 33 with a gap width of about 1 mm to 10 mm, in particular of about 2 mm. Through the gap 33, the maximum adjustment range for Adjustment of the roller holder 27 relative to the frame holder 26 defined.

To realize the required in the setting of the roller 21 actuating movements can or the desired contact pressure between the roller 21 and to apply the roller 22 are distributed in the gap 33 over the circumference total four actuators 34 in the form of pressure hoses 34, of which in FIG. 1 only two are shown in section, arranged. About not shown in Fig. 1 Feed lines 48 (see FIG. 4) can be formed by the walls of the actuators 34 Pressure chambers 36 are pressurized. Depending on the particular Pressure conditions in the four actuators 34 acts on the roll holder 27 a resulting force, so by appropriate control of the pressure in the actuators 34, the roller 21 is pressed against the roller 22 with the desired contact pressure can be. Because the air cushion pressurized in the actuators 34 is compressible is, mechanical disturbances can be caused by the resulting spring action be intercepted.

For fixing the roller holder 27 relative to the frame holder 26 are on the roll holder 27 Lammellenelemente 37 attached to the attached to the sleeve body 29 Lammellenelementen 38 arranged to form a Lammellenpakets combing are. For frictional obstruction of the Lammellenelementen 37 and 38th formed Lammellenpakets 37 and 38 is a cross-sectionally T-shaped punch 39th provided, the circular punch head 40 with an annular flange 41 at the outermost Lammellenelement 37 and 38 of the Lammellenpakets to the plant comes. At the opposite end of the punch 39, a pressure plate 42 is attached, on which the spring force of a trained in the manner of a plate spring package 43 Spring element 43 acts. The spring element 43 is biased between the pressure plate 42 and the sleeve body 29 mounted so that of the Lammellenelementen 37 and 38 formed Lammellenpaket by the spring force from the punch 39 on the Lammellenelemente 37 and 38 is transmitted, is clamped.

For adjusting the roller holder 27 relative to the frame holder 26, in particular during Adjusting the contact pressure between the rollers 21 and 22 must be that of the Lammellenelementen 37 and 38 or the punch 39 and the pressure plate 42 formed fixing device can be solved. This is in the base plate 28 a Pressure port 44 is provided through which a pressure chamber 46 between the Pressure plate 42 and the base plate 28 with a pressure medium, such as compressed air can be applied. As soon as the pressure acting on the pressure plate 42 the air pressure Spring force of the spring element 43 exceeds, the punch 39 is far from the outermost Lammellenelement 37 and 38 lifted, that this no longer frictionally clamped are and can be moved relative to each other.

The adjustment of the contact pressure between the rollers 21 and 22 takes place, for example in the following way. First, the pressure chamber 46 with a sufficient pressure acted upon, so that the Lammellenelemente 37 and 38 no longer frictionally be pinched. Subsequently, the actuators 34 each with just as much pressure urges that the desired contact pressure between the rollers 21 and 22 or between the roller 21 and others, not shown in Fig. 1 Rolling forms and leads to a contact strip of the desired width. As soon as the correct setting with the desired contact pressure between the rollers 21 and 22 is found, the pressure chamber 46 is depressurized, whereby the punch 39 the Lammellenelemente 37 and 38 clamped together, so that the roller holder 27 relative is fixed to the frame holder 26 in the desired position. Last will be the actors 34 depressurises.

In Fig. 2 and 3, the operating principle of the device 20 in the required adjusting movement shown in a schematic way. Fig. 2 shows the frame holder 26 with the Recess 31 and the engaging portion 32 of the roller holder 27. Through the choice of dimensions is between the frame holder 26 and the section 32nd the roller holder 27, a gap 33 is formed, in which the in Figs. 2 and 3 only schematically indicated by force arrows actuators 34 are arranged. The possible Adjusting movements between the frame holder 26 and the roll holder 27 are by an actuating plane, which is in the representation of Fig. 2 and 3 in the plane of the drawing extends, defined, wherein the adjustment range of the adjusting movements by the width of Slits 33 is limited.

As shown by way of example in FIG. 3, the roll holder 27 and, as a result, the attached thereto roller 21 are laterally offset relative to the frame holder 26, which by a corresponding control of the actuators 34 and the consequent Force effect on the section 32 is effected. Once the desired position of Roller holder 27 is found relative to the frame holder 26, which can be from the Lammellenelementen 37 and 38 or the punch 39 and the pressure plate 42 formed fixing device are actuated, so that the position is permanently fixed and the actuators 34 need not be driven further.

In Fig. 4, the device 20 with base plate 28 in a perspective view of shown in front. The sleeve body 29 is by means of four fastening screws 47 on the Base plate 28 attached (see Fig. 1, shown schematically). Between the Sleeve body 29 of the frame holder 26 and the roller holder 27, on the after Front side of the half-shell-shaped quick release 24 partially visible is (see Fig. 1), the four formed in the manner of pressure hoses 34 actuators 34 arranged, which can be acted upon via leads 48 with compressed air. through the pressure plate 42, the recognizable Lammellenelemente 37 and 38 relaxed become.

One recognizes the extremely compact design of the device 20, due to their total rotationally symmetrical design (apart from the base plate 28) a smaller diameter than the roller 21 itself (see Fig.1).

FIG. 5 shows a second exemplary embodiment of an actuator 50 for a device 20 in FIG Cross-section. The basic structure of the device 20 with frame holder 26, Roller holder 27 and a fixing device for fixing the roller holder 27 relative to the roll holder 26 corresponds to the structure described with Fig. 1 and therefore must will not be explained further. To form the actuator 50 is in the gap 33 a cylindrical membrane 51, whose upper and lower edges with the inner diameter the sleeve body 29 is connected (not shown in Fig. 5) arranged. The Membrane 51 is also in four strip-shaped areas 52 with the Inner diameter of the sleeve body 29 connected, for example glued, so As a result, through the sleeve body 29 and the diaphragm 51 four pressure chambers 53rd are formed, which are distributed uniformly over the circumference of the gap 33. The Pressure chambers 53 can each have pressure inlet openings 54 with compressed air be acted upon, so depending on the pressure in the four pressure chambers 53, a resultant force acts on the portion 32 of the roll holder 27.

In Fig. 6, an inking unit 56 is shown, with which of a roller 57 printing ink on a can be transferred in the manner of a forme cylinder 22a formed roller 22a. to Transfer of ink are in the inking unit 56 five adjustable rollers 21a; 21b; 21c; 21d; 21e provided. The ends of the adjustable rollers 21a to 21e are respectively in FIG Devices 20 mounted, which indicated in Fig. 6 by the corresponding actuators 34 is.

Also, four or five rollers 21a; 21b; 21c; 21d; 21e, For example, set up a dampening roller and three or four inking rollers become.

By pressurizing the respective actuators 34, the rollers 21a; 21c; 21e are employed on the roller 22a. After employment of the rollers 21a; 21c; 21e can by pressurizing the various actuators 34 on the rollers 21a to 21e, the contact pressure between the various rollers 57; 21a to 21e; 22a be set.

On the roller 22a is one or more fasteners 58 or Interruptions 58 are provided, which are designed in particular in the manner of a gap 58 is. In the fastening device 58, the front and rear edge of a Pressure plate are fixed to attach the pressure plate to the roller 22a. Of the Rotation angle of the roller 22a is detected by a sensor, not shown, and to the Control forwarded. When adjusting the rollers 21a; 21c; 21e or at the Adjustment of the contact pressure of these rollers 21a; 21c; 21e will be the respective Angle of rotation of the roller 22a taken into account, thereby preventing the rollers 21a; 21c; 21e when hiring or when adjusting the contact pressure at the Interrupt 58 are present. The setting of the rollers 21a to 21e or their Adjustment to the roller 22a can also be used with a rotating printing unit with a rotating roller 22a done. The adjustment of the contact pressure and / or the employment of the first Rolls 21a to 21e to the second roller 22a takes place at low speeds, especially at 3,000 to 5,000 U / h ..

The switching device 59 shown in Fig. 7 is suitable for driving the a total of 20 actuators on the adjustable rollers 21a to 21e on one side. The Switching device 59 is shown only schematically and is below briefly explained.

From a pressure accumulator 61, a pressure medium, such as compressed air with be taken sufficiently high pressure level. Via two valves 62; 63 in particular pressure control valves 62; 63, the pressure medium flows into two separate Pressure chambers 64; 66, in which, depending on the position of the pressure control valves 62 and 63 there is a corresponding pressure level. Associated with each actuator 34 Pressure lines 67, the set in the pressure chambers 64 and 66, the pressure to the Actuators 34 are transmitted.

The changeover of the changeover device 59 is clocked. The duration of a time clock for Adjustment of an adjustable roller 21a to 21e of the inking unit 56 or dampening unit is 0.1 to 2 seconds, especially 0.5 seconds.

In the switching device 59 are now in Fig. 7, not shown shut-off devices, For example, provided shut-off valves, so that optionally different to the Pressure chambers 64 and 66 connected pressure lines 67 are shut off can. If now the contact pressure to be set on an adjustable roller 21, so All pressure lines 67 are shut off, which lead to actuators 34, for the Setting are not required. In the result it follows that the by the Pressure control valves 62; 63 regulated air pressure transmitted only to the actuators 34 be involved in the setting of each desired roller 21. After Setting this roller 21, the corresponding contact pressure by pressing the Fixed fixing, so that by switching the switching device 59th then the next adjustable roller 21 can be adjusted.

Instead of the switching device 59 with shut-off device is the following alternative possible.

The of both pressure control valves 62; 63 set air pressures are applied simultaneously the actuators 34; 50 of several adjusters. Only with the Adjustments in which the fixing is opened is done a setting.

The roller 21 to be started; 21a; 21b; 21c; 21d; 21e, the lateral surface of the second roller 22; 22a with respect to the circumferential direction at a distance of less than 20 mm from the leading end of the interruption 58 takes place.

Adjusting the contact pressure means that the contact pressure in the salaried state (in contact) of the roller to another roller before hiring or hired Condition is changeable, d. H. the surface pressure of the roller is in addition to parked condition changeable.

LIST OF REFERENCE NUMBERS

01 to 19

-

20

contraption

21

roller

22

roller

23

axis

24

quick release

25

-

26

frame holder

27

roller holder

28

Base plate (26)

29

Sleeve body (26)

30

-

31

Recess (26)

32

Section (27)

33

gap

34

Actuator, pressure hose

35

-

36

pressure chamber

37

Lammella element (27)

38

Lamellar element (26)

39

stamp

40

ram head

41

Flange (40)

42

printing plate

43

Spring element, plate spring package

44

pressure connection

45

-

46

pressure chamber

47

fixing screw

48

supply

49

-

50

actuator

51

membrane

52

attachment section

53

pressure chamber

54

Pressure inlet port

55

-

56

inking

57

roller

58

Fastening device, interruption, gap

59

switchover

60

-

61

accumulator

62

Valve, pressure control valve

63

Valve, pressure control valve

64

pressure chamber

65

-

66

pressure chamber

67

pressure line

21a

roller

21b

roller

21c

roller

21d

roller

21e

roller

22a

Roller, forme cylinder

Claims (7)

Method for adjusting the contact pressure between an adjustably mounted first roller (21; 21a; 21b; 21c; 21d; 21e) and at least one second roller (22; 22a) and / or for turning on or off the first roller (21; 21a; 21b; 21c; 21d; 21e) to the second roller (22; 22a) in a printing machine, with at least one actuator (34; 50) to which the first roller (21; 21a; 21b; 21c; 21d; an adjustable force is pressed in the direction of the second roller (22; 22a), wherein the second roller (22; 22a) has an interruption (58) on its lateral surface, characterized in that the adjustment of the first roller (21; 21a; 21b 21c; 21d; 21e) takes place only at certain angular positions of the second roller (22; 22a) outside the interruption (58). Method according to Claim 1, characterized in that a plurality of rollers (21; 21a; 21b; 21c; 21d; 21e) are placed against the second roller (22; 22a) and the adjustment of these rollers (21; 21a; 21b; 21c; 21d 21e) takes place outside the interruption (58). A method according to claim 1, characterized in that the second roller (22a) in the form of a forme cylinder (22a) with a fastening device (58) for fixing the pressure plate on the forme cylinder (22a) is formed, and the adjustment of the contact pressure and / or 21e; 21e; 21e; 21e; 21e; 21e) on the forme cylinder (22a) only in angular positions in which the first roller (21a; 21b; 21c; 21d; 21e) does not rest against the fastening device (58) Plant can come. Method according to claim 1 or 3, characterized in that the adjustment of the contact pressure takes place with rotating rollers (21; 21a; 21b; 21c; 21d; 21e; 22; 22a). A method according to claim 4, characterized in that the setting of the contact pressure and / or the setting of the first roller (21; 21a; 21b; 21c; 21d; 21e) to the second roller (22; 22a) at low speeds, in particular at 3,000 up to 5,000 U / h., takes place. A method according to claim 1, characterized in that the roller (21; 21a; 21b; 21c; 21d; 21e) to be set is at a distance of less than 20 mm from the leading end relative to the peripheral direction of the lateral surface of the second roller (22; 22a) the interruption (58) touched. Method according to Claim 5, characterized in that all rollers (21a, 21c, 21e) which can be set against a forme cylinder (22; 22a) have their own actuator (34; 50).

Images