The invention relates to pump inking units of a printing press, as well as to a printing group having a pump inking unit in accordance with the preamble of claim 1 or 2 or 27.
In contrast to customary film inking units, in pump inking units the amount of ink to be introduced into the inking unit is not provided by means of inking blades, but by means of exact metering via valves and/or pumps. This takes place in an exactly tailored manner for each individual ink color zone, for example. For reasons of expense and/or structural space, in some cases the supply of a defined pressure level is provided for several color zones arranged side-by-side in the axial direction, wherein metering can be individually regulated per color zone or group of color zones, for example, by valves.
A pump inking unit of a printing press is known from DE 698 09 580 T2, wherein a defined amount of ink can be metered through respective supply openings by means of several metering pumps onto axially adjacent areas of a roller shell surface, and wherein several of the metering pumps are arranged side-by-side in the axial direction of the inking roller in an applicator strip. The metering pumps are embodied as gear pumps or other suitable positive-displacement pumps.
In a pump inking unit, DE 26 26 006 A1 discloses displacement pumps embodied as sickle-tooth gear pumps, having an externally-toothed interior rotor and an internally-toothed exterior rotor, whose axes of rotation are seated eccentrically in respect to each other. A sickle-shaped insert element is provided in the blending space for forming a suction and a pressure chamber.
A pump inking unit is disclosed in DE 20 43 078 which, in one embodiment, has several pumps side-by-side, in particular gear pumps, between a common feed line and each of the respective bores of a distributor block.
A metering pump embodied in the form of a rotatory displacement pump with an externally-toothed interior rotor and an internally-toothed exterior rotor is shown in EP 0 852 674 B1 and in the material of a prospectus of the HNP Mikrosysteme GmbH company of Parchim, whose axes of rotation are seated eccentrically in respect to each other, wherein the exterior and the interior rotors have a cycloid-shaped tooth arrangement, whose cycloid-shaped tooth arrangement is in meshing engagement and forms a system of several sealed conveying chambers in the course of rotation.
The object of the invention is based on creating pump inking units of a printing press, as well as a printing unit with a pump inking unit.
In accordance with the invention, the object is attained by means of the characteristics of claim 1 or 2, or 27.
The advantages to be obtained by means of the invention lie in particular in that a compact pump inking unit is created, which is highly precise in respect to metering.
The advantages over a conventional film inking unit, which can be attained by a pump inking unit, appear in the form of a simpler basic setting, start-up and/or ink curve determination. The influence of changes in the basic setting, such as film roller spacing, bending of the doctor device (or the doctor roller), etc., is reduced. Improvements can be achieved in the resolution of the actuating steps, in particular in the range of narrower surface-covering degrees.
In contrast to single- or double-piston pumps, clearly evened-out conveyance can be achieved (low pulsation, small lost volume) by the employment of gear pumps or annular gear pumps, in a special embodiment by rotatory displacement pumps with an externally-toothed interior rotor and an internally-toothed exterior rotor. Such a pump (also called a metering pump in what follows) is known, for example, from HNP Mikrosysteme GmbH. It can be produced with an extremely small structural space and has a high precision in metering accuracy.
Because of the small structural space it is now possible to provide an individual pump per ink zone—in particular side-by-side in the axial direction—directly at the applicator strip. Preferably each one of the pumps has its own motor and, in an advantageous variation, its own control unit for the driving thereof.
In another embodiment, the pump is designed as a gear pump, for example internally-toothed gear pump or externally-toothed gear pump. In this case each pump can preferably have its own motor, and in an advantageous embodiment its own control unit, for example a control board.
Exemplary embodiments of the invention are represented in the drawings and will be described in greater detail in what follows.
Shown are in:
As already described above,
In an exemplary embodiment of the pump inking unit in accordance with the invention represented in FIGS. 2 to 10, the conveyance or metering of the ink in the pump inking unit takes place by means of pumps 11, which are based on the micro-tooth ring principle, such as is known, for example, by relevant prospectus material of the HNP Mikrosysteme GmbH company; in particular by means of rotatory displacement pumps with an externally-toothed interior rotor 12 and internally-toothed exterior rotor 13, which are seated slightly eccentrically in respect to each other. Conveying chambers 14, formed on the aspirating side 14 between the exterior and the interior rotors 12, 13, increase in size in the course of the rotation of the rotors around their offset axes, while they are simultaneously decreased in size on the pressure side 17. In
Advantageously, the tip diameter of the interior rotor 12 substantially corresponds to the root diameter of the exterior rotor 13, decreased by the tooth depth, or the reference diameter of the interior rotor 12 substantially corresponds to the reference diameter of the exterior rotor 13, reduced by half the tooth depth. The presence of several closed conveying chambers 14 is made possible in this way, for example.
As represented in a schematic sectional view in
Two embodiment variations of the spatial arrangement of the metering pump 24 (with a motor 27 and a coupling connecting the motor 27 with the metering pump) are represented in
Lines or conduits leading from the ink supply strip 26 to an inlet of the metering pump 24, and from an outlet of the latter to the delivery opening 04, are also indicated. Because of the highly viscous ink, a cross section in the area of the inlet and/or outlet to or from the metering pump 24 (and preferably the conduits) should for example be at least 10 mm2, in particular at least 15 mm2. In particular, with a maximally operationally required volume flow Vmax (for example 10,000 or 15,000 mm3), a minimal cross sectional surface Q should be selected in such a way that Q≧1/(1,000 mm)*Vmax applies. Preferably this should apply to the entire supply path between the ink supply strip 26 to the (kidney-shaped) inlet opening 16 and/or from the (kidney-shaped) outlet opening 17 to the delivery opening 04.
The pump 24 (here the pump mechanism with externally-toothed interior rotor and internally-toothed exterior rotor), the driveshaft 32 and the barrier seal 31 are represented enlarged and in section in
Advantageous characteristics for laying out and/or operating the metering pump, or a characterization of an advantageous dimensioning of the metering pump are shown in the following table.
( . . . .): Values in parentheses apply to headset printing
(1)measured with a rotatory viscosimeter, plate-cone system, opening angle 0.3°, temp. 20° C.
(4)to be able to place the individual metering pumps side-by-side on the ink applicator strip, the width of the pump plus the drive mechanism should not exceed the stated value
In this case a maximum width b24, b27, b36 of the pump 24 and/or of the motor 27 and/or, if applicable, of a flange 36 holding the pump 24, which is less than 50 mm, in particular maximally 35 to 43 mm, in the axial direction of the inking unit, is of particular importance (see
Here, the metering pump 24′ is embodied as an externally-toothed gear pump 24′ and has two gear wheels 37, 38, which mesh with each other, wherein only their pitch circles are represented. One of the gear wheels 37, 38 is driven via a shaft 39. In the course of driving the gear wheels in the direction indicated by the arrows, ink is transported from the area of the inlet opening 16′ between the teeth into the lower area of the outlet opening 17′. A return transport is prevented by the engagement of the teeth in the contact point, and the ink is transported out of the outlet 17′. The second gear wheel 38 can be merely rotatably seated.
The same as for the first embodiment of the metering pump 24, it can be advantageous to again provide a barrier seal 31′ and/or a coupling 29. The barrier seal 31′ can be embodied in the manner of the above mentioned barrier seal 31 with a pressure chamber 34 containing hydraulic fluid. However, in another advantageous embodiment it contains an elastic material which is under pressure and is arranged in the space between the shaft 39 and a housing of the barrier seal. The pressure on the elastic material 42, for example an elastomer, can be applied for example by means of a fluid, a gel, or also by grease. When employing a gel or grease, this can be introduced through a valve 43 or a connecting piece 43, which is to be closed afterward. In this case a supply system, such as required in connection with the embodiment of the hydraulic fluid-operated barrier seal 31, would not be necessary.
In a non-represented variation, the metering pump 24 can also be embodied as an internally-toothed pump.
For all embodiments in accordance with the invention, its own control unit 41, for example a control card 41, can be assigned to each metering pump 24, 24′, besides its own motor 27. It can preferably also be arranged, for example at the assigned motor 27, 27′, in numbers corresponding to the motors 27, 27′ on the applicator strip 06. However, a reduced number of control cards 27 can be provided in the area of the applicator strip 06, which then is respectively assigned to two, three or more motors 27, 27′. In principle it is also possible to arrange the control cards 41, or a common control card 41, structurally separated from the applicator strip 41.
Since with the described arrangement the amount of ink can be introduced into the inking unit in zones or as a whole via the control of the metering pumps 24, 24′, it is no longer required to operate the doctor roller 07 at a speed in regard to the required amount of ink which is a relative speed in comparison to the film roller 08. Therefore, in a first variation the doctor roller 07 does not require its own drive motor, which is mechanically independent of the film roller 08, but instead it can be driven via a mechanical driving connection by another roller of the inking unit. In a second variation, the doctor roller 07 can have its own drive motor which, however, is operated at fixed relative rpm in regard to the inking unit during the operation of the printing press. It is operated in such a way that the doctor roller operates at rpm which are proportionate to the production speed.
The pump inking unit is represented in the roller train of a printing group 44 in
In the ideal case, the forme and transfer cylinders 52, 53 are therefore individually driven by at least one drive motor 54 (individually, as shown on the right by way of example, or coupled in pairs by a common one, as shown on the left by way of example), at least one distribution cylinder 47, 49 by a drive motor 46, as well as the metering pumps 24, 24′ by at least one drive motor 27, 27′. Advantageously the feed pressure can also be adjusted by a motor which is mechanically independent of the mentioned motors.
Two printing groups 44 in the form of a double printing group in
01 Pump, oblique-shaft (double) piston pump
02 Feed line
03 Feed line
04 Delivery opening
05 -
06 Applicator strip
07 Roller, doctor roller
08 Film roller
09 Ink application roller
10 -
11 Pump
12 Interior rotor
13 Exterior rotor
14 Conveying chamber
15 -
16 Aspirating side, inlet opening
17 Pressure side, outlet opening
18 Pump, condenser
19 Ink reservoir, feed container
20 -
21 Pressure regulator, pressure reducer
22 Feed line
23 Filter
24 Metering pump, pump (pump mechanism)
25 -
26 On-site reservoir, ink supply strip
27 Drive mechanism, motor
28 Line
29 Coupling
30 -
31 Barrier seal
32 Driveshaft
33 Seal
34 Pressure chamber
35 -
36 Flange
37 Gear wheel
38 Gear wheel
39 Shaft
40 -
41 Control unit, control card
42 Elastic material
43 Valve, connecting piece
44 Printing group
45 -
46 Drive motor
47 Distribution cylinder
48 Ink transfer roller
49 Distribution cylinder
50 -
51 Application roller
52 Forme cylinder
53 Transfer cylinder
54 Drive motor
55 -
56 Web
57 Printing location
58 Printing unit, printing tower
b24 Width
b27 Width
b36 Width
P Pressure
P0 Pressure (feed line)
Number | Date | Country | Kind |
---|---|---|---|
10 2004 045 673.9 | Sep 2004 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP05/54621 | 9/16/2005 | WO | 3/19/2007 |