JPS59138456A - Inking device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an inkjet printer having a diameter corresponding to the effective working diameter of the plate, having a rubber skin, and rolling over this plate surface at a speed corresponding to the circumferential speed of the plate. Ink for printing machines with a hard plate, which rolls and can be driven at different speeds and has at least two further rollers delimiting the ink reservoir and having a steel jacket, and which handles highly viscous inks. Regarding equipment.

A device of this kind is disclosed in German Patent Application Publication No. 311 of the Federal Republic of Germany.
No. 9789. In this known device, both ink sump rollers are constructed as steel rollers with a smooth surface, the sump roller being closer to the printing form being the ink sump roller further away from the printing form. Rotate faster. In this case, the quantity of ink removed from the ink fountain is metered by adjusting the gap between the two ink fountain rollers and by adjusting the speed difference of the two ink fountain rollers. When processing different inks with different viscosities, the gap width and speed difference must be constantly adjusted again in the known device. The same applies if the viscosity changes during operation, for example due to temperature changes in the ink or an increase in dampening agent content. It can therefore be seen that the known device is not operationally advantageous in such cases.

The object of the invention is therefore to improve an inking device of the type mentioned at the outset by simple and therefore cost-effective measures, so that it can be operated very conveniently and yet To ensure accurate metering of the amount of ink removed from the reservoir.

According to the present invention, this problem can be solved by constructing the roller closer to the plate among the rollers that partition the ink reservoir as a metering roller, and the steel outer skin of this metering roller forming an ink storage recess and a roller that is closer to the plate.
It has a mesh formed by protrusions provided between these ink storage recesses, and among the rollers that partition the ink reservoir, the roller that is farther from the plate has a mesh formed by the roller that is closer to the plate. configured as a scraping roller attached to the roller, the steel skin of the scraping roller being rotated under pressure at a different speed than the scraping roller;
The solution is that the steel shell of the roller closer to the plate can be compressed.

The different/different speeds of the two rollers which delimit the ink sump together with their mutual suppression ensure that the scraping roller can scrape the metering roller reliably, so that the scraping roller guides the ink only in the area of the ink receiving recess. . In this case, the different speeds produce a scraping effect for scraping off the ink, so that not only reliable scraping of the projections but also good filling of the ink receptacles is ensured. Therefore, each time the metering roller rotates, an amount of ink that is fixedly determined by the volume of the ink receiving recess is taken from the ink reservoir by the mesh of the metering roller, and in this case, regardless of the viscosity of the ink, it is necessary to adjust or adjust the gap. This makes the operation very advantageous.

A further characteristic of the means according to the invention is that the two rollers, which are brought together under pressure and which define the ink reservoir, pass through a mesh to
Advantageously, by obtaining sufficient lubrication by the ink entrained from the ink sump, dry rotation of the ink sump rollers, and thus high mutual rubbing and high roller wear, is eliminated. In this case, it is advantageous for the steel-steel material combination to ensure a high pressing force in order to compensate for eccentricities, etc., without fear of pumping effects, etc. Furthermore, the method according to the invention allows very thin ink I to be applied to the plate surface.
can be applied. In this connection, it must be provided that the scraping roller, which cooperates with the metering roller, not only scrapes off the projections of the mesh, but also removes the ink from the ink-receiving recess by splitting the ink. The ink that has accumulated in the ink receiving recesses is now split up on this latter roller in the area of contact between the metering roller and the roller arranged after this metering roller and during the inking of the printing plate. undergo at least one more fission process.

These means therefore already bring the ink deposits arranged in front of the metering roller and the printing form into direct action with the rollers, so that precise inking can be carried out on the rollers and thus also on the printing plate surface. This inking can be achieved particularly precisely if there is another steel roller between the metering roller and the inking roller, which rotates faster than the metering roller and at the same speed as the inking roller. is,
This steel roller spreads out the ink applied by the metering roller, thereby doubling the splitting effect.

An inking device is known from German Patent Application No. 31 17 341, which is provided with a roller having a mesh. However, this roller does not act as a roller delimiting the ink fountain, but rather is colored by a submerged roller that dips into the ink fountain and is scraped off by a doctor.

Compared to devices of this type, the device according to the invention is distinguished by low construction and maintenance outlays.

According to an advantageous embodiment of the invention, the two rollers delimiting the ink reservoir can be designed as mesh rollers (9). In this case, the mesh on both sides ensures a complete filling of the two ink receiving recesses, despite the ink splitting that takes place in the area of contact between the two ink receiving recesses.

Therefore, it can be seen that this embodiment is extremely advantageous especially when a large amount of ink is required.

In a further advantageous embodiment of the invention, the mesh of the metering roller and/or the scraping roller cooperating with this metering roller is approximately twice as fine as the mesh of the printing form. This ensures reliable coloring of the printing form even if the ink viscosity changes drastically.

Another advantageous measure provides that at least one of the two ink sump rollers which are accessible to one another under pressure has a tubular jacket, which jacket is supported by a shaft supported on the jacket via at least one support piece. The shaft end, which is penetrated with radial clearance and projects from this skin, has a variable deflection compensator, i.e. a compensator for the deflection lines of the ink fountain rollers that cooperate with each other. Since the pressure can be applied by the device,
Uniform mutual contact is ensured over the entire length of the rollers.

Further advantageous embodiments of the invention, in connection with the remaining exemplary embodiments, appear in the drawings (and will become apparent from the following description of some exemplary embodiments).

The inking device shown in FIG. 1 consists of an ink fountain row 21 with a rubber jacket and two further rollers 3 or 4 which delimit the ink fountain 2. The inking device shown in FIG. The ink reservoir 2 is delimited in the area of the end faces of the associated rollers 3 or 4 by metal plates 5, which contact the flat roller end faces to prevent ink from leaking. connected to the tank for supplying fresh ink to the ink sump 2;
A pump, not shown, can be provided here. In the ink reservoir, the roller 1 is in contact with a plate cylinder 6, and a printing plate forming a plate is attached to this plate cylinder. All rollers transfer to each other. The diameter of the ink reservoir roller 1 corresponds to the effective operating diameter (11) of the plate cylinder 6 to which the hard plate is attached. In the ink reservoir, the circumferential speed of roller l matches the circumferential speed of the plate. By these measures, it is possible to avoid so-called stenciling effects, in which the printing elements of the printing form are no longer sufficiently pigmented.

The two rollers 3, 4 which delimit the ink reservoir 2 are constructed as steel rollers with a steel jacket, which increases the stability, reduces the tendency to deformation and thus also increases the mW. Wear. The steel outer skin of the ink reservoir roller 3, which is closer to the plate, has ink storage recesses 7 shown enlarged in FIG. It has a mesh formed by The mesh of this mesh roller is advantageously finer, preferably twice as fine, than the mesh of the printing form on the printing form cylinder 6, thereby ensuring reliable coloring of the printing form. The two rollers 3 or 4 which define the ink reservoir 2 are brought close to each other under pressure and driven at different speeds for scraping off the projections 8 and filling the ink receiving recesses 7. Therefore (12) In this case the roller acts as a scraping roller.

Since the two rollers, which can be approached by pressure, are constructed as steel rollers, there is no need to fear a pumping effect due to hydraulic pressure. In this case, the ink is conducted only through the ink receiving recess 7 of the roller 3, so that the amount of ink taken out from the ink reservoir 2 is fixedly determined by the capacity of the ink receiving recess 7 of the roller 3. Roller 3 thus forms a metering roller. Good lubrication is achieved by the ink passing through the mutual contact area of both rollers 3°4.
That is advantageous for wear.

To get closer to the pressure, both sump rollers 3
, 4 can be coupled with a suitable operating device.

Advantageously, this is the rear sump roller 4 furthest from the printing form. The ink sump roller 3, which is configured as a mesh roller and is closer to the forme, is driven to rotate slightly faster than the ink sump roller 4 further from the forme, which cooperates with this ink sump roller (13). can. In experiments, good results have been obtained at three times the speed.

Due to the speed difference between both rollers 3 and 4, the ink storage recess 7
The ink that has fallen off is scraped off, which ensures reliable ink entrainment by the mesh. Due to the scraping effect, only a small portion of the ink in the ink receiving recess 7 breaks up onto the roller 4 with a smooth surface. The ink that remains in the ink storage recess 7 is then transferred to the roller I, which in FIG.

In this case, the ink pool has a higher affinity for the ink on row 23 than the ink on roller 1, so only a small portion of the ink reaches roller l, resulting in a very thin but complete ink film. This ink reservoir is obtained on the roller. The diameter of the roller 3, which is configured as a mesh roller, is υ smaller than the diameter of the ink reservoir roller 1, which rotates at the same circumferential speed. As a result, the mesh roller and the ink reservoir become roller 1.
It is ensured that the meshes can roll over each other so that uniform inking is achieved by the equalization (14) rabbets and creases.

The inking device as described above makes it possible in particular to process highly viscous inks due to the mesh. In the case of offset inks, therefore, a dampening device, generally indicated at 9, preferably constructed as a brush dampening device, can be attached to the inking device. In this case, the dampening agent is applied directly to the printing plate.

In the embodiment on which FIG. 2 is based, the rollers 3 or 4 which partition the ink reservoir 2 are formed by ink receiving recesses 7 and projections 8 provided between these ink receiving recesses. It has a mesh pattern. In this case, the mesh on both sides ensures that the ink-receiving recess 7 is completely filled despite the ink splitting in the contact area. The speeds of these two mesh rollers are different, as mentioned above. In the embodiment shown, the ink sump roller 3 which is closer to the form is driven at a slightly higher speed, preferably three times higher, than the mesh roller 4 (15) which is further away from the form. The ink reservoir roller 3, which is closer to the plate, can cooperate with the roller 1 for direct ink deposition, as described above. In the illustrated embodiment 1, the ink deposit is made of another steel material with a smooth surface between the roller 1 and the ink reservoir roller 3 which is closer to the plate. The roller 10 is arranged such that the circumferential speed of this roller corresponds to the circumferential speed of the roller 1 and the ink layer cooperates with the roller, where 1 is slightly higher than the ink sump roller 3, which is configured as a mesh roller. , is driven preferably three times higher. This spreads the ink transferred from the ink reservoir roller 3 to the roller 10.

The further configuration of the embodiment according to FIG. 2 corresponds to the device according to FIG. 1, and reference may be made to the description with respect to FIG. 1 to avoid repetition.

The ink sump rollers 3 or 41d, as already mentioned above, are subjected to pressure and are brought closer to each other.

(16) For this purpose, it is advantageous if the lateral axle of the ink sump roller 4 remote from the printing form can cooperate with a suitable pressing device. To ensure that there is uniform contact and therefore also uniform pressing force over the entire length of the roller,
One of the two ink sump rollers, in the embodiment shown the one furthest from the printing form, is provided with a deflection compensator which compensates for the deflection of the ink sump roller 4 with respect to this ink sump roller. It is possible to match the deflection of the ink sump row 23 which acts together. For this purpose, the roller 4, as shown in FIG. 3, includes a tubular jacket 11, which is coaxially penetrated by a shaft 12 with a radial clearance. The outer skin 11 is
It is provided with lateral shaft necks 13 pierced by the ends of the shaft 12, which can be connected to the pressing device, indicated here only by the arrow 14, via a radial rocking support piece (not shown). Supported. The drive can take place via a drive element 15 mounted on one of the axes j. The shaft 12 is
The shaft 12 and the outer skin (17) are supported on the outer skin 11 by two support pieces configured as swing support pieces, which communicate the spacing between the shaft 12 and the outer skin (17) 11. The support bearings 16 are arranged symmetrically with respect to the center of the skin and are distributed over the length of the skin in such a way that the spacing of the supporting pieces corresponds approximately to one-third of the length of the skin. The end 17 of the shaft 12, which projects from the lateral shaft neck 13 of the skin 11, engages the operating devices indicated here only by arrows 18, these operating devices being connected to the press housing or as shown in the figure. Advantageously, it is supported by a restraining device [4] attached to the axle neck 13 as in the embodiment. Suppression device 14 and operating device 1
8 can actually be constructed as a hydraulic or pneumatic cylinder-piston assembly. By energizing the actuating device 18 the skin 11 can be deflected over the shaft 12, so that the deflection of this skin corresponds to the deflection of the roller co-acting with the skin, which ensures a uniform push over the entire length of the roller. Create pressure. Advantageously, the actuating device 18 can be restrained so that the set deflection is maintained. In order to distribute the heat generated in the area (18) of the support piece 16 evenly over the entire skin 11, the annular space between the skin II and the shaft 12 can be provided with oil that partially fills this annular space. . Another type of deflection compensation device consists in the roller being pressed against the shaft neck to prevent deflection. For this purpose, pressure screws can be provided which are supported on the printing press frame and whose bearings surrounding the shaft necks cooperate with these shaft necks via the housing.

[Brief explanation of the drawing]

1 is a side view of a first embodiment with one mesh roller, FIG. 2 is a side view of another embodiment with two mesh rollers, and FIG. 3 is an ink reservoir with variable bending compensation device. It is a sectional view of a roller. 1... Ink is deposited on a roller, 2... Ink reservoir, 3.
4...Roller, 7...1 ink storage recess, 8...
Projection piece (19)

Claims (1)

[Scope of Claims] 1. An ink sump roller (1) having a diameter corresponding to the effective working diameter of the plate, provided with a rubber skin, and rolling over the plate surface at a speed corresponding to the circumferential speed of the plate; At least two further rollers (3 or 4) rolling on each other and driveable at different speeds, delimiting the ink reservoir (2) and having a steel skin, handle viscous ink. In an inking device for uneven printing that handles a hard plate, the ink reservoir (2
), the roller (3) that is closer to the plate is configured as a metering roller, and the steel outer skin of this metering roller has an ink storage recess (7) and an ink storage recess (7) for these ink storages. Of the rollers (3, 4) that have a mesh formed by the pieces (8) provided between the recesses and partition the ink reservoir (2), the roller (4) that is farthest from the plate is attached to the plate. It is configured as a scraping roller attached to the metering roller formed by the closer roller (3), the copper skin of which is rotated under pressure at a speed different from that of the scraping roller. The roller closest to the plate (3)
2. Both rollers (3, 4) that partition the ink reservoir (2).
2. The inking device according to claim 1, wherein the inking device has a mesh. 3. In accordance with one of the claims 1 and 2, characterized in that the mesh of the roller (3) or of the rollers (3, 4), which is configured as a mesh roller, is approximately twice as fine as the mesh of the printing form. Inking device as described. 4. The inking device according to claim 1, wherein the rollers (3, 4) that define the ink reservoir (2) have the same diameter. 5. that the roller (3) with the mesh, which is closer to the plate, can be driven at a higher speed, preferably three times as high, than the roller (4), which is further from the plate and cooperates with this roller; An inking device according to any one of claims 1 to 4. 6 The roller closest to the plate (3) is connected to another copper roller (10
), this steel roller acts in conjunction with the ink reservoir (2)
The adjacent roller (3 or 4) that has the same diameter as the roller (3 or 4) that partitions the ink td, contacts the ink cleaning roller (1) that has a larger diameter, and that partitions the ink td.
One of claims 1 to 5, characterized in that the ink cleaner can be driven at a peripheral speed that is higher than the peripheral speed of 4), preferably 3 times higher, and that matches the peripheral speed of the roller. The inking device described in . 7. One of claims 1 to 6, characterized in that at least one of the rollers (3, 4) that partition the ink reservoir (2) is equipped with a deflection compensator.
The inking device described in . 8. The roller (3 or 4) with the deflection compensator can be subjected to a compensating force in the region of the axle neck, which can preferably be applied by means of a compression screw. Inking device. 9 At least one of the two rollers (3, 4) delimiting the ink reservoir (2), which can be pressed against each other, is connected to the tubular jacket (1).
1), this skin is penetrated with radial clearance by a shaft (12) supported on this skin via at least one support piece, and the skin (11) is elevated i+! 8. Inking device according to claim 7, characterized in that the end (17) of the lit (12) can be subjected to pressure by a +l operating device (18). 10. The end of the outer skin (11) is supported by the suppression device (14), and the operating device (18) attached to the shaft end (17) is
The inking device according to claim 9, characterized in that it is supported by a pressing device (14) that comes into contact with the inking device.