Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F9/00—Rotary intaglio printing presses
  • B41F9/02—Rotary intaglio printing presses for multicolour printing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F9/00—Rotary intaglio printing presses
  • B41F9/06—Details
  • B41F9/061—Inking devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F31/00—Inking arrangements or devices
  • B41F31/02—Ducts, containers, supply or metering devices
  • B41F31/06—Troughs or like reservoirs with immersed or partly immersed, rollers or cylinders
  • B41F31/07—Troughs or like reservoirs with immersed or partly immersed, rollers or cylinders for rotogravure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F9/00—Rotary intaglio printing presses
  • B41F9/06—Details
  • B41F9/061—Inking devices
  • B41F9/066—Enclosures
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F9/00—Rotary intaglio printing presses
  • B41F9/06—Details
  • B41F9/08—Wiping mechanisms
  • B41F9/10—Doctors, scrapers, or like devices
  • B41F9/1036—Clamping and adjusting devices

Definitions

• the present invention relates to a printing group for rotogravure printing presses.
• Printing presses of the rotogravure type are provided with different printing stations, each of which is intended for a single colour.
• Each station comprises a printing group composed of a cylinder on which the image to be printed is etched and against which the continuous strip, onto which the image is to be transferred, is pressed by a pressure roller.
• the impression cylinder is inked by means of an inking roller partially immersed in an inking tray.
• a blade known as a "doctor" in technical jargon, lightly presses against the impression cylinder so as to remove the excess ink and form a film of ink on the etched or engraved zone of the impression cylinder.
• Each printing group which comprises, as is known, the impression cylinder, the inking roller and the doctor, is also provided with accessory elements such as a device for adjusting the correct position of the doctor and an ink collecting tray.
• the continuous strip on which the image is printed passes in succession between the impression cylinder and pressure roller of the various printing stations, in each of which one of the colours of the image to be printed is impressed onto the strip itself.
• the object of the present invention is that of reducing considerably the time required for replacement of the impression cylinder and of performing washing of the entire printing group and in particular the doctor, automatically, without the help of operators in order to avoid problems associated with the health of the operators themselves.
• a further object is that of performing always automatically all the necessary adjustments of the doctor depending on the extension of the impression cylinder and the angle of inclination of the doctor itself, by means of the action of a single operator who enters the aforementioned data on a processor. It has been found that with the device according to the present invention, the replacement times are reduced about tenfold compared to the times necessary with the known printing groups.
• FIGS. 2 and 3 show a plan view of the doctor with the associated device for adjusting the position with respect to the impression cylinder;
• FIG. 5 shows a side view of the device for raising and inserting the impression cylinder
• - Figure 6 shows a front view of the device according to Fig. 5;
• Figures 7, 8 and 9 show the system for washing the impression cylinder and the tray in two operating positions of the doctor.
• 1 denotes a printing station in a printing press of the rotogravure type, in which station there is provided, in the bottom zone, a printing group 2 above which a system of rollers 3 for conveying a continuous film 4 is positioned.
• the printing group comprises an impression cylinder 5 against which the continuous film 4 is pressed by means of a pressure roller 6.
• the impression cylinder is acted on by a doctor 7 supported by an adjusting device 8 which will be illustrated in greater detail below.
• an ink containing tray 9 housing an idle inking roller 10 kept pressed against the impression cylinder by two pneumatic cylinders 11 which support the entire tray by means of an intermediate frame 12.
• the entire printing station 1 is enclosed between metal walls inside a chamber (50) in which there are provided only two slits 13 and 14 for passage of the film 4, the rear wall being provided with an inspection and maintenance hatch 15.
• the doctor 7 is fixed by known means, which are not described here, onto a bar 16 which is able to rotate about a horizontal pivot 17 or perform a translatory movement vertically since the said bar is supported by two vertical columns 18 sliding in bushes 19 integral with the frame of the printing station; the two columns 18 are connected together at the bottom by means of a cross-piece 20.
• Each column has milled on it a rack 21 which meshes with a pinion 22 keyed onto a shaft 23 supported by two supports 24.
• the shaft 23 is driven by means of an electric motor 25 connected to a reducer 25a keyed onto said shaft.
• the shaft 23 On the opposite side to the driving system, the shaft 23 has keyed onto it an encoder 26 designed to detect the number of revolutions of the shaft 23 itself.
• Two end-of-travel stops 27 and 28 determine the maximum travel or vertical displacement of the doctor-carrying bar 16.
• the rod of each cylinder 29 is connected to a ball joint 31 which is connected to the bar 16.
• the doctor adjusting device described above via connection of the encoder and the electric motor to a processor, allows the position of the doctor to be adjusted automatically depending on the diameter of the impression cylinder; in short, the operator must simply set the diameter of the cylinder and the working angle of the doctor on the computer and automatically the electric motor will perform a predetermined number of rotations so as to bring the doctor into an optimum position, whereas the angular position is determined by the cylinders 29.
• the working angle of the doctor is chosen depending on various factors such as, for example, the quality of the inks, the incisions on the cylinder and the like.
• 32 denotes a pneumatic cylinder with opposing rods, the rod 33 of which is connected to an arm 35a of a lever 35 pivotably mounted at 36.
• the rod 37 of the cylinder 32 is connected to the frame of the station and allows horizontal translation of the cylinder and the lever 35, while the rod 33 imparts a thrusting force to the impression cylinder (5) so as to push it out of the working position.
• the lever 35 has an arm 35b which is inserted underneath the impression cylinder.
• the impression cylinder 5 rolls on two horizontal guides 38 so as to end up on a carriage not illustrated.
• the two rods 33 and 37 move out simultaneously so as to cause raising and thrusting of the impression cylinder.
• the lever 35 is arranged in the position shown in broken lines and indicated by (a) so as to prevent the impression cylinder from dropping suddenly onto the support rollers 39.
• two pneumatic cylinders 32 which operate two levers 35 located at the two ends of the impression cylinder.
• the washing system comprises a duct 40 located on the doctor side and having engaged on it a plurality of nozzles 41 with a jet directed substantially towards the point of contact of the doctor with the impression cylinder and a plurality of nozzles 42 with the jet directed towards a baffle 43 for guiding into the tray.
• Another duct 44 is positioned on the other side of the tray and has a plurality of nozzles 45 with the jet directed towards the impression cylinder and a plurality of nozzles 46 with the jet directed towards the walls of the tray.
• Figure 9 shows in broken lines the position of the tray 9 in the lowered position.
• the ducts 40 and 44 are able to rotate about their longitudinal axis so as to adapt to the different positions and orientations of the doctor upon variation in the diameter of the impression cylinder.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Inking, Control Or Cleaning Of Printing Machines (AREA)
• Rotary Presses (AREA)
• Electronic Switches (AREA)
• Ink Jet (AREA)
• Retarders (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (2)

Family

ID=11396025

Family Applications (1)

Country Status (9)

Cited By (3)

Families Citing this family (7)

Citations (7)

• 1996
  • 1996-09-30 IT IT96PR000036A patent/IT1288050B1/it active IP Right Grant
• 1997
  • 1997-08-26 ES ES97942177T patent/ES2174289T3/es not_active Expired - Lifetime
  • 1997-08-26 CN CN97198416A patent/CN1110412C/zh not_active Expired - Fee Related
  • 1997-08-26 AU AU43958/97A patent/AU720109B2/en not_active Ceased
  • 1997-08-26 EP EP97942177A patent/EP1009634B1/en not_active Expired - Lifetime
  • 1997-08-26 JP JP10516353A patent/JP2001501146A/ja not_active Ceased
  • 1997-08-26 DE DE69710929T patent/DE69710929T2/de not_active Expired - Fee Related
  • 1997-08-26 KR KR10-1999-7002730A patent/KR100516100B1/ko not_active IP Right Cessation
  • 1997-08-26 WO PCT/IT1997/000215 patent/WO1998014329A2/en active IP Right Grant

Patent Citations (7)

Also Published As

Similar Documents

Legal Events