Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F35/00—Cleaning arrangements or devices
  • B41F35/04—Cleaning arrangements or devices for inking rollers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41P—INDEXING SCHEME RELATING TO PRINTING, LINING MACHINES, TYPEWRITERS, AND TO STAMPS
  • B41P2235/00—Cleaning
  • B41P2235/10—Cleaning characterised by the methods or devices
  • B41P2235/20—Wiping devices
  • B41P2235/21—Scrapers, e.g. absorbent pads

Definitions

• the present invention relates to a doctor device according to the preamble of claim 1.
• washing devices which comprise spray nozzles or similar means for applying a cleaning liquid to the surface to be cleaned, and a doctor blade device which serves to press a flexible doctor blade against the surface wetted with the washing liquid and so on wipe off the washing liquid together with the paint dissolved in it.
• the ink solution obtained in this way runs into a trough of the doctor device and is removed via this.
• ink residues remain on such a conventional doctor device, which have to be removed by hand, since they would otherwise dry on the doctor and would damage the surface of the roller to be cleaned if they were used again.
• the invention has for its object to provide a doctor device.
• the advantages that can be achieved with the invention are, in particular, that due to the retractability of the doctor blade in the tub and the closability of the tub, drying of ink onto the doctor blade when not in use can be avoided.
• the trough generally has an elongated shape with a slot-shaped opening for the emerging squeegee, a possibility for closing the trough can be created in a simple manner by designing the trough in the form of a cylindrical chamber, around the axis of which the closure element between one open and a closed position is rotatable.
• the closure element is preferably arranged within the chamber.
• the movement of the squeegee between the protruding position from the trough and the lowered position is preferably a swiveling movement, and an actuator for driving this swiveling movement is provided on the squeegee device.
• the squeegee is preferably elastically deformed in the lowered position.
• closure element can be pivoted by the same actuator which also drives the movement of the doctor between the position protruding from the tub and the lowered position.
• the tub be provided with an inlet and an outlet for a cleaning liquid.
• the cleaning liquid can be pumped through the tub at a high flow rate in the closed state in order to become tough over time To remove squeegee adhering paint residues and rinse them away.
• the inlet and outlet lead to opposite end sections of the trough.
• the doctor device preferably also comprises a pump for circulating cleaning liquid through the trough.
• This pump can expediently be assigned a control device which is coupled to the position of the closure element and, when the chamber is closed, permits a higher throughput of the pump than when the chamber is open. Letting a stream of cleaning liquid flow, even if it is weak, with the chamber open makes sense in order to continuously rinse off any ink residues that the doctor blade wipes off the roller surface to be cleaned during the operation of the doctor blade device.
• the flow rate with the chamber open must be selected low enough so that cleaning fluid does not splash out of the opening of the chamber. In contrast, when the chamber is closed, significantly higher flow rates of the cleaning liquid can advantageously be used.
• This circuit expediently has at least one filter element for separating paint residues from the flow of the cleaning liquid.
• Figure 1 is a schematic section through a first embodiment of a doctor device, in which the doctor is extended from the chamber.
• FIG. 2 shows a schematic section through the doctor blade device from FIG. 1, in which the doctor blade is sunk into the tub;
• FIG. 3 shows an axial section along the line III-III from FIG. 1;
• FIG. 4 shows a section analogous to that of FIG. 1 through a second embodiment of the doctor device
• FIG. 5 shows a section through the doctor blade device according to a second embodiment, with the doctor blade lowered
• Fig. 6 in a block diagram of the doctor device.
• FIG. 1 shows a schematic section through a doctor blade device 01 with a doctor blade 03 placed on an inking roller 02 of a printing press.
• the inking roller 02 is only shown in sections, on a quarter of its circumference.
• the doctor blade 03 is a strip of a flexible plastic or rubber material which extends at least over the active axial width of the inking roller 02.
• a longitudinal edge 04 of the doctor blade 03 lies in that in FIG. 1 shown extended position of the doctor blade 03 on the surface of the ink roller 02.
• An opposite longitudinal edge 06 of the doctor blade 03 is in a cylindrical sector-shaped closure element 07, z. B. clamped a holding element 07.
• the holding element 07 is rotatably received in a cylindrical chamber 08 of a tub 09.
• the tub 09 is composed of two opposite end plates 11 and a jacket 12 connecting the two end plates 11.
• the jacket 12 has essentially the shape of a cylinder, with an elongated opening 13, for. B. a slot 13 on its upper side and one on one edge of the slot 13 bent outward, elongated tab 14, which serves as a support 14 for the doctor blade 03 when wiping the ink roller 02.
• Both end plates 11 are provided with a bore 16, to each of which a supply line or discharge line 17 for a cleaning liquid is connected.
• a nozzle bar (not shown) sprays a cleaning liquid over the entire width of the jacket of the inking roller 02.
• the inking roller 02 rotates counterclockwise with respect to FIG. 1.
• the doctor blade 03 presses against the surface of the ink roller 02 at an acute angle. The friction that occurs increases the pressure between the doctor blade 03 and the ink roller 02 and also presses the doctor blade 03 against the supporting tab 14 of the tub 09.
• Mixture carried on the surface of the ink roller 02 of cleaning liquid and ink residues is stripped from the squeegee 03 and flows downwards into it Trough 09, where it is carried along by a cleaning liquid stream which flows through the trough 09 in the longitudinal direction from the inlet to the outlet 17.
• the throughput of the cleaning liquid in this state is just sufficient to ensure that the paint residues are reliably washed away and do not deposit in the tub 09. For this, it is not necessary for the flow to fill the entire cross section of the tub 09.
• the holding element 07 After cleaning the inking roller 02, the holding element 07 is rotated together with the squeegee 03 about the longitudinal axis A of the chamber 08 into the position shown in FIG. 2.
• the holding element 07 runs out at its two longitudinal ends in a cylindrical ring 18 which is closed in the circumferential direction and which exactly fills the inner cross section of the likewise cylindrical chamber 08.
• an external toothing 19 is formed, which meshes with a pinion 21.
• the pinions 21 at both ends of the tub 09 are driven by the same servomotor, not shown.
• the external teeth 19 are each protected by sealing rings 22 against the infiltration of washing liquid and possibly color.
• FIG. 2 shows the squeegee device 01 in a configuration in which the holding element 07 with the squeegee 03 is rotated less than 180 ° clockwise compared to the configuration of FIG. 1.
• the doctor blade 03 is in a fully retracted position in the chamber 08.
• the longitudinal edge 04 of the doctor blade 03 presses against the jacket 12 of the tub 09, and the doctor blade 03 is in itself elastically bent.
• the holding element 07 blocks the slot 13, so that the holding element 07 and the jacket 12 form a tube which is closed all round.
• cleaning liquid is pumped through the chamber 08 at high speed in order to clean the doctor blade 03.
• FIG. 2 shows the squeegee device 01 in a configuration in which the holding element 07 with the squeegee 03 is rotated less than 180 ° clockwise compared to the configuration of FIG. 1.
• the doctor blade 03 is in a fully retracted position in the chamber 08.
• the longitudinal edge 04 of the doctor blade 03 presses against the jacket 12 of the tub 09, and
• the retracted doctor blade 03 divides a small area 23 from the cross section of the chamber 08, which does not communicate directly with the bores 16 on the end plates 11 of the tub 09 and in which therefore there is no significant flow of the Cleaning fluid occurs.
• this is of no importance for the effectiveness of the doctor blade cleaning, since the side surface of the doctor blade 03 which delimits the region 23 is not reached when the ink-cleaning liquid mixture is wiped off from the ink roller 02 and remains clean.
• it is no problem to produce a cleaning liquid flow in this area e.g. B. in which the position of at least the bore 16 connected to the feed line in its End plate 11 is displaced so that at least a part of its cross section opens onto the area 23.
• Fig. 4 shows a second embodiment of a doctor device 01 in a representation analogous to Fig. 1.
• the same elements that are present in both embodiments are given the same reference numerals and will not be described again.
• the squeegee device 01 from FIG. 4 is designed for an ink roller 02 rotating clockwise in the perspective of this figure.
• the squeegee 03 is composed of a rigid squeegee lip 24 made of plastic and a spring 26, e.g. B. a leaf spring 26 which extends like the squeegee lip 24 over the entire width of the ink roller 02.
• the leaf spring 26 is screwed on the one hand to the squeegee lip 24 and on the other hand to a holding element 07 which has the same functions as the holding element 07 from FIG. 1.
• the tab 14 of the embodiment from FIG. 1 is replaced by a rail 27 screwed to the jacket 12, which holds the free longitudinal edge 04 of the doctor blade 03 pressed against the inking roller 02.
• the rail 27 can be removed to access the interior of the tub 09 for maintenance and repair purposes.
• Inlets and outlets 17 for cleaning liquid are not led through the end plates 11, but close to the opposite ends through the jacket 12 of the tub 09.
• doctor blade 03 When the doctor blade 03 is in the retracted position shown in FIG. 5, it divides the free interior of the chamber 08 into two areas 23, 28.
• the feed line 17 is arranged in such a way that it points onto the Area 23 opens out, which is delimited by the side surface of doctor blade 03 bearing the stripped paint.
• the discharge line 17 opens into the area 28.
• a cleaning liquid flow pumped through the supply and discharge lines 17 through the chamber 08 not only rinses the chamber 08 in the longitudinal direction, but also forces the doctor blade 03 a little way from the jacket 12 into the interior of the chamber 08 back so that a narrow gap is formed along the longitudinal edge 04 of the doctor blade 03, through which the cleaning liquid passes from the area 23 into the area 28 at high speed. In this way, highly effective cleaning is achieved in particular of the longitudinal edge 04 provided for contact with the ink roller 02.
• Two rubber sealing strips 29 are embedded in the body of the holding element 07 and rotate with it. They are placed in such a way that they come to rest on both sides of the slot 13 in the closed configuration shown in FIG. 5 and reliably prevent the cleaning liquid from escaping to the inking roller 02.
• the doctor device 01 also comprises a pump 30, which circulates the cleaning liquid in a closed circuit.
• the pump 30 is coupled to a control circuit 32, which also drives the servomotor 33 for the pivoting movement of the holding element 07 and the doctor blade 03.
• the control circuit 32 Coupled to the respective position of the holding element 07, the control circuit 32 regulates the throughput of cleaning liquid to a low value with an open value and a high one, a turbulent one Cleaning liquid flow favoring value when the position is closed.
• Filters 31 for catching ink residues dissolved in the cleaning liquid are also arranged in the closed circuit, so that the doctor device 01 can be operated maintenance-free for a long time.

Landscapes

• Inking, Control Or Cleaning Of Printing Machines (AREA)
• Coating Apparatus (AREA)
• Beans For Foods Or Fodder (AREA)
• Polarising Elements (AREA)
• Cereal-Derived Products (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=33426736

Family Applications (1)

Country Status (6)

Families Citing this family (7)

Citations (3)

Family Cites Families (6)

• 2003
  • 2003-05-08 DE DE10321189A patent/DE10321189B4/de not_active Expired - Fee Related
• 2004
  • 2004-05-04 EP EP04731068A patent/EP1620267B1/de not_active Expired - Lifetime
  • 2004-05-04 DE DE502004001742T patent/DE502004001742D1/de not_active Expired - Fee Related
  • 2004-05-04 US US10/554,809 patent/US7392744B2/en not_active Expired - Fee Related
  • 2004-05-04 JP JP2006506572A patent/JP2006525149A/ja active Pending
  • 2004-05-04 WO PCT/IB2004/001384 patent/WO2004098891A1/de not_active Ceased
  • 2004-05-04 AT AT04731068T patent/ATE342166T1/de not_active IP Right Cessation

Patent Citations (3)

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