EP0713771B1 - Cleaning device for rotating elements in printing machines - Google Patents

Description

The invention relates to a washing device for Rotary body in printing machines according to the preamble of claim 1.

A comparable washing device of this type is out German patent DE 40 10 957 C2, DE 39 03 434 C2 and EP 0 573 801 A1. You serve for cleaning blanket cylinders in an offset printing machine.

However, the present invention is not based on the Cleaning of blanket cylinders in offset printing machines limited, but can generally in Printing machines for washing rotating bodies are used, for example by Blanket cylinders, printing plate cylinders, Impression cylinders, inking rollers, Dampening rollers, idlers etc.

The washing device according to DE 40 10 957 C2 contains a washing roller, which in a tub-like housing is rotatably mounted. Both extend in the essentially over the entire length of the to be cleaned Cylinders. The case is on its two each end arranged on a slide, which together with the housing on one Machine frame across a straight track to the cylinder to be cleaned is adjustable to the Wash roller on the outer surface of the to be cleaned Put on cylinders or move them away from her. For this purpose is a linear drive cylinder on the slide, for example a hydraulic cylinder, attached, for actuating a guided in it Piston, which is supported on an eccentric, the rotatable about an axis mounted in the machine frame is. To put the washing roller on the one to be cleaned The cylinder becomes the piston of the linear drive cylinder always extended to its full stroke so that the extended position of the washing roller only from the Setting of the eccentric is dependent. The setting is such that in the extended position Washer roller abuts the cylinder to be cleaned. The Housing is on a swivel axis with the slide pivotally connected, such that by means of a Swivel-piston-cylinder unit with the housing Wash roller can be pivoted about the pivot axis can. The cylinder of the swing-piston-cylinder unit is attached to the sled and its piston presses against the housing. The swivel axis is through a Square shaft formed, of which an edge as Scraper edge or squeegee in the outer surface of the Washing cylinder engages when the housing with the Wash cylinder is pivoted about the pivot axis. On the washing roller is a fabric cover as Washing element. The force with which the washing roller applies the blanket cylinder is turned on by the Pressurization of the swivel cylinder-piston unit given, this actuation pressure on a kept constant value of, for example, 30 bar becomes. The constant pressurization of the swivel-piston-cylinder unit has a certain pressure the washing roller to the blanket cylinder. An automatic compensation is found possible wear of the washing roller cover instead.

The function of the known washing device is following: In the rest position, the washing roller is from the blanket cylinder. To pre-wet the Wash cover of the washing roller is made via nozzles Wash liquid sprayed onto the roller cover and that Housing is pivoted up about the pivot axis, so that the squeegee edge scrapes off the wash roller cover. This Operation can be done in the same way to clean the Wash roller can be used after the Has cleaned blanket cylinder and then again from Blanket cylinder was distanced. To wash the Blanket cylinder becomes the housing with the washing roller advanced by the linear drive cylinders which be extended to their full stroke. Here comes the washing roller on the blanket cylinder to the system. The Force with which the washing roller on the blanket cylinder is pressed by the swivel-piston-cylinder unit certainly.

The scraping effect of the doctor edge is thereby disturbed that the outer surface of the blanket cylinder is uneven where the rubber blanket on Cylinder is attached so that the unevenness Washer roller bounces around and small swiveling movements makes the pivot axis, whereby the contact pressure of the Doctor edge on the washing roller is affected. Of the The square bar used as a doctor blade is caused by the friction worn with the washing roller. The doctor rod is expensive and takes a lot of time to replace.

The object of the invention is to achieve the develop known washing device so that it is constructive and easier to use, whereby the contacting and decontacting as well as the Contact pressure of the squeegee regardless of the contact pressure the washing roller on the rotating body to be cleaned should be adjustable, such that bumps on the Surface of the rotating body to be cleaned none have an adverse effect on the squeegee function. Further the washing device should be designed so that the squeegee becomes cheaper and exchanged faster can be.

This object is achieved according to the invention by the Features of claim 1 solved.

As piston-cylinder units are preferred hydraulic units can be used instead but also pneumatic or electric piston-cylinder units be used.

According to a special embodiment of the invention is the washing roller in a tub-like housing rotatably mounted on at least one carrier arranged and on this support relative to him and relative to the rotating body together with the washing roller is adjustable transversely to the axis of rotation of the washing roller, such that the washing roller in the area of a Housing opening optionally on the rotary cylinder can be created or distanced from it, whereby the housing around the axis of rotation of the wiping element is not is rotatably arranged relative to the carrier. Through the Non-rotatability of the housing is avoided in washing liquid available to him from the housing is distributed.

Another preferred embodiment is that as a doctor blade from a doctor blade rust-resistant spring steel is used, which is interchangeable and rotatable in such a way that either one longitudinal edge or the other longitudinal edge of the Spring band steel as a squeegee edge with the washing roller cooperates. The washing roller preferably has one Metal cylinder on which there is an elastic covering e.g. made of rubber. There is a on the topping Washing element, e.g. a stocking-like washcloth cover applied interchangeably.

Further features of the invention are in the Subclaims included.

Fig. 1

schematisch eine Seitenansicht einer Waschvorrichtung nach der Erfindung für einen Rotationskörper in einer Druckmaschine, beispielsweise einen Gummituchzylinder in einer Offset-Druckmaschine,

Fig. 2

schematisch eine Seitenansicht auf die Waschvorrichtung von Fig. 1 von rechts in Richtung eines Pfeiles II gesehen,

Fig. 3

eine schematische Querschnittsansicht längs der Ebene III-III von Fig. 2,

Fig. 4

eine Querschnittsansicht längs der Ebene IV-IV von Fig. 2,

Fig. 5

eine Querschnittsansicht längs der Ebene V-V in Fig. 2.

The invention is described below with reference to the drawings using a preferred embodiment as an example. Show in the drawings

Fig. 1

schematically a side view of a washing device according to the invention for a rotary body in a printing press, for example a blanket cylinder in an offset printing press,

Fig. 2

schematically a side view of the washing device of FIG. 1 seen from the right in the direction of an arrow II,

Fig. 3

2 shows a schematic cross-sectional view along the plane III-III of FIG. 2,

Fig. 4

3 shows a cross-sectional view along the plane IV-IV of FIG. 2,

Fig. 5

3 shows a cross-sectional view along the plane VV in FIG. 2.

The washing device according to the invention can on be of different types. According to the Drawings just a single wash roller or in modified embodiment also two or more Have washing rollers. This one or more Wash rollers can be attached to a rotating body at the same time or alternately or to different ones Rotational body can be created. According to a special one Embodiment it is also possible to use a washing roller or several washing rollers alternately between several To move bodies of revolution back and forth and thereby each to one or the other as needed Rotating body to be created alternately.

In the drawings, a rotating body is shown schematically 2 of a printing press, which by one Rotation axis 3 is rotatable and its lateral surface 4th continuously or periodically or as required by the Washing device is cleaned according to the invention. Of the Rotating body 2 can be a blanket cylinder, a Plate cylinder, one impression cylinder, one Inking roller, a dampening roller, a guide roller or idler or other rotating body. The printing press can, for example, be an offset printing press, however one after another Process printing press. Of the Rotary body 2 is one in the side parts 6 Machine frame rotatably supported.

The washing device according to the invention contains one Wash roller 8, which is rotatable about an axis of rotation 10 in a tub or tub-like housing 12 is rotatably mounted. The axis of rotation 10 of the Washing roller 8 runs parallel to the rotation axis 3 of the Rotating body 2. The washing roller 8 can according to FIG. 3 from a core 14 in the form of a metal tube, a elastic covering 16 e.g. made of rubber, and an as Wash element acting cover 18 exist. The coating 18 consists of a material which is washing liquid can take up, preferably plush, terrycloth or a Loop fabric with a variety of small Thread loops, which have a good cleaning effect when Wipe the rotating body 2 to be cleaned. In the housing 12 is on his from Rotating body 2 facing away from a variety of Nozzles 20 for spraying washing liquid, for example water and / or solvents to which outer lateral surface 22 of the washing roller 8. the nozzles 20 are preferably against the washing roller 8 directed that part of the washing liquid on their Shell surface 8 and another part of the Washing liquid on a stripping device 24 meets. The stripping device 24 is used for stripping the lateral surface 22 of the washing roller 8 in order Washing liquid and dirt from the outer surface 22 to strip and squeeze out of the coating 18. A washing liquid supply line 26 is via a Distribution line 28 to the nozzles 20 in terms of flow connected. The used washing liquid will collected on the bottom 30 of the housing 12, then over a not shown Reprocessing system cleaned, and then again fed to the nozzles 20.

The stripping device 24 has a cross section square rectangular shaft 32, whose central longitudinal axis 34 parallel to the axis of rotation 10 of the Washer roller 8 runs and at the same time the axis of rotation is around which the shaft 32 can rotate. The wave 32 has cylindrical end portions 36 which over Bushings 38 are rotatable in end walls 40 of the housing 12 are stored, as shown in FIG. 5. In the housing 12 are attached to a plurality of bearing blocks 42, which cylindrical intermediate sections 44 of the shaft 32 support to prevent the shaft 32 from bending. On an outer surface of the square shaft 32 is a Doctor blade 46 made of stainless material, preferably made of rust-resistant spring steel, interchangeable attached that it against another doctor blade can be exchanged and that it is optional can be rotated that either one longitudinal edge 48 or its other longitudinal edge 50 as a doctor edge the washing roller 8 cooperates. The active squeegee edge 48 lies on the side facing the rotating body 2 Side on a theoretical connecting line which the axis of rotation 10 of the washing roller 8 with the Axis of rotation 34 of the shaft 32 connects. The active one Squeegee edge 48 has a small distance in the rest position from the lateral surface 18 of the washing roller 8, as shown in the drawings shown in solid lines and can be positioned by means of a positioning device 52 5 about the axis of rotation 34 in a working position be pivoted in which they are in the coating 18 of the Washer roller 8 presses as this in dash-dotted lines Lines are shown in Figs. 4 and 5. In the Working position squeezes the active doctor edge 48 Washing liquid and dirt out of the coating 18. For this purpose, the washing roller 8 according to FIG Motor 54, for example a hydraulic motor driven so that the washing roller 8 with respect to 1, 3, 4 and 5 clockwise accordingly an arrow 56 rotates. This direction of rotation 56 of Wash roller 8 is preferably the same as that Direction of rotation 58 of the rotating body 2 to be cleaned, so that their opposite each other Surface areas run opposite to each other. The directions of rotation 56 and 58 can also be opposite to each other provided that Circumferential speeds of the washing roller 8 and Rotational body 2 are so different that a differential movement or wiping movement between these two rotating bodies.

The positioning device 52 has in each housing end wall 40 a piston-cylinder unit 58 with a in the housing end wall 40 cylinders 60 and a piston 62 which can be extended from the cylinder. On the shaft 32 is a radially protruding from it Lever arm 64 attached in a rotationally fixed manner. If not activated Piston-cylinder unit 58 is the piston 62 in its retracted position in cylinder 60, 5, and the doctor blade 46 is in its illustrated in Figs. 3 and 4 Rest position, in which the lever arm 64 the in Fig. 5th position shown in solid lines. At retracted piston 62, the shaft 32 comes with the Doctor blade 46 either by its own weight, the Center of gravity eccentric to the axis of rotation 34 of the shaft 32 lies, or by a compression spring 66, which optionally can be used and press on the lever arm 64 can, in the rest position according to FIGS. 3, 4 and 5. By activating the piston-cylinder unit 58 her piston 62 with a certain force against the Lever arm 64 pressed so that the shaft 32 with the Doctor blade 46 is pivoted about the axis of rotation 34 and the active doctor edge 48 with a pressure which is the Force corresponds to the piston-cylinder unit 58 against pressed the coating 18 of the washing roller 8. Of the Path of movement of the piston 62 from its cylinder 60 and is the angle of rotation of the shaft 32 about its axis of rotation 34 not by stops, but only by back pressure the roller 8 limited to the doctor edge 48. Thereby results for a certain force of the piston 62 Piston-cylinder unit 58 always exactly predetermined contact pressure of the active doctor edge 48 on the washing roller 8, regardless of possible Material wear of the doctor edge 48 or the Lateral surface of the washing roller 8 and regardless of Manufacturing tolerances and assembly tolerances of the Washing device. Of course, attacks can be provided to the maximum range of motion of the piston 62 and the rotational movement of the shaft 32 limit, but then these attacks are so arranged that they are outside the range of motion which are in normal function for the Swiveling movement of the doctor blade 46 about the axis of rotation 34 and the necessary stroke movement of the piston 62 are necessary. The cylinder 60 of the piston-cylinder unit 58 can according to FIG. 5 each in the end wall 40 of the Housing 12 be screwed. The piston-cylinder unit 58 preferably works hydraulically, can also work pneumatically or electrically.

It is important that an appropriate hydraulic pressure or Pneumatic pressure or an electromagnetic force of certain strength can be generated. If the Washer roller 8 is short, it may be enough in or on only a housing end wall 40 a piston-cylinder unit 58 to provide the positioning device 52. For lengths of more than 50 cm, however, it is advisable to get one uniform contact pressure of the active doctor edge 48 to get their entire length when on both front ends of the housing 12 each have a piston-cylinder unit 58 is used. According to one, not Modified embodiment shown is also possible a positioning device 52 within the To arrange the length of the shaft 32 elsewhere.

Above was only the one in the drawings, in particular Fig. 3 shown below Stripping device 24 described. Depending on the type of cleaning rotary body or the printing press or of the material to be printed on one Rotating body 2 a plurality of stripping devices 24 be provided simultaneously or alternately to be used. 3 is diametrical as an example a second, identical to the washing roller 8 trained scraper 24/2 with a Doctor blade 46/2 shown.

The front end sections of the tub-like or trough-like housing 12, at the housing end walls 40, are carried by guide bodies 70 and are on these guide bodies 70 by means of a Washer roller positioning device 72 perpendicular to Rotation axis 10 of the washing roller 8 and thus also perpendicular to the axis of rotation 3 of the to be cleaned Rotating body 2 can be moved in a straight line and thereby between a washing position and a non-washing position adjustable. In the non-washing position the washing roller 8 has a distance from it cleaning rotary body 2 according to Fig. 1. In the washing position, the washing roller 8 is on the Shell surface 4 of the rotating body 2 to be cleaned on. The two guide bodies 70 are on the Side parts 6 of the machine frame attached and protrude towards each other towards the center of the machine. The Wash roller positioning device 72 points to each front end of the housing 12 one on it attached piston-cylinder unit 74, whose pistons 76 at right angles to the Rotation axes 3 and 10 from the piston-cylinder unit 74 is extendable and adjustable Stop 78 supports, which on the associated Guide body 70 is attached. The adjustable Stop 78 is shown schematically in Fig. 1 as Eccentric disc shown, its angular position determines where the washing roller 8 each in the Washing position and the non-washing position. This piston-cylinder unit 74 can be designed in this way be that the piston 76 each when pressurized is fully extended, the adjustable Stop 78 is set so that at extended piston 76, the washing roller 8 am Rotating body 2 abuts, but with the retracted Piston 76 the washing roller 8 from the rotating body 2 is distant. The piston-cylinder unit 74 for Linear displacement of the washing roller 8 across Rotary body 2 can be hydraulic or pneumatic or be an electro-magnetically operated unit. It is preferably a hydraulically operated unit. If your piston 76 with the associated stop 78 is mechanically connected, then he can the washing roller 8th from the washing position to the non-washing position withdraw. If such a connection between the Piston 76 and the stop 78 is not available one or more compression springs 80 between a paragraph the guide body 70 and the housing 12 are used be around the housing 12 and thus the washing roller 8 from the washing position to the non-washing position push back.

According to another embodiment, not shown it is also possible to use the washing roller 8 alone a washing roller positioning device 72 alternately between the washing position and the non-washing position to adjust while at the same time housing 12 the side parts 6 of the machine frame stationary remains.

The length of the washing roller 8 is approximately the same as the length of the rotating body 2. According to modified Embodiments, the washing roller 8 can be shorter or be longer and / or it can be over the length of the Rotating body 2 distributes several shorter washing rollers 8 or more complete washing devices used will.

According to an embodiment, not shown Wash roller 8, with or without the housing 12, by means of Washing roller positioning device 72 not straight, but along an arcuate trajectory to the Rotational body 2 can be put on and by him again removable.

Claims (9)

1. Washing device for rotating members (2) in printing machines with the following features: a washing roller (8) rotatably mounted and drivable round an axis of rotation (10); means (70, 72) for placing the washing roller (8) with its external surface (18) on the external surface (4) of the rotating member (2) to be cleaned; a fluid applicator (20) for applying washing fluid to the external surface of the washing roller (8); at least one stripping device (24) for stripping the external surface (18) of the washing roller (8), the stripping device (24) being variable in angle round a pivot axis (34) extending parallel to the axis of rotation (10) of the washing roller (8); characterised in that the pivot axis (34) of the stripping device (24) is formed by a shaft (32) which is mounted rotatably and variably in angle in a body (12) in which the washing roller (8) is also rotatably mounted, in that the stripping device (24) comprises a doctor blade (46), in that the doctor blade (46) has an elongate shape in the form of a strip extending in the longitudinal direction of the washing roller and has two stripping edges (48, 50) formed by the two longitudinal edges of the doctor blade and in that the doctor blade (46) is detachably fastened on the shaft (32) such that it can be exchanged and can be selectively rotated through 180° and fastened on the shaft (32) to allow one or other stripping edge (48, 50) to cooperate selectively with the washing roller (8).
2. Washing device according to claim 1, characterised in that the doctor blade (46) is a strip of stainless spring steel.
3. Washing device according to one of the preceding claims, characterised in that the stripping edge (48) of the stripping device (24) lies on the downward side, in terms of movement, of a theoretical connecting line with respect to the direction of rotation (56) of the washing roller (8), the connecting line connecting the axis of rotation (10) of the washing roller (8) to the pivot axis (34) of the stripping device (24).
4. Washing device according to one of the preceding claims, characterised in that several, at least two, stripping devices (24, 24/2) are arranged round the periphery of the washing roller (8).
5. Washing device according to one of the preceding claims, characterised in that two stripping devices (24, 24/2) are arranged on two diametrically opposed peripheral points of the washing roller (8).
6. Washing device according to one of the preceding claims, characterised in that the stripping device (24) is arranged freely rotatably round its pivot axis (34), in that a positioning device (52) is provided which pivots the stripping device (24) with a predetermined constant force round its pivot axis (34) toward the external surface (18) of the washing roller (8) from a rest position into a working position in which the positioning force of the positioning device (52) is in equilibrium with an opposing pressure exerted on the stripping device (24) by the washing roller (8) and in that the positioning device (52) on the one hand is supported (62, 64) in the direction of its force on the stripping device (24) and on the other hand is supported (40, 60) in the direction opposed to this force on the body (12), in which the washing roller (8) and the stripping device (12) are each mounted rotatably round their separate axes (10, 34).
7. Washing device according to claim 6, characterised in that the positioning device (52) has at least one hydraulic, pneumatic or electric piston cylinder unit (58) of which the force can be adjusted to the stripping device (24).
8. Washing device according to claim 6 or 7, characterised in that a second positioning device (72) is provided and in that the body (12) is arranged and guided, preferably rectilinearly guided, on a machine frame (6, 70) such that it can be adjusted by the second positioning device (72) between a non-washing position in which the washing roller (8) is spaced from the rotating member (2) to be cleaned and a washing position, in which the washing roller (8) rests on the rotating member (2), without the distances and angular positions of the washing roller (8) and the stripping device (24) being varied relative to one another.
9. Washing device according to one of the preceding claims, characterised in that the fluid applicator has a plurality of nozzles (20) which are distributed over the length of the washing roller (8) and are directed toward the external surface of the washing roller (8) such that a proportion of the jet of washing fluid flows from at least some of these nozzles (20) past the washing roller (8) onto the stripping device (24).

Images