EP0097085B1 - Inking device with lower duct blade and removable ink fountain - Google Patents

Description

The invention relates to an inking device for use in a printing machine, for example an offset machine.

A rotary printing machine comprises a number of printing elements each comprising a plate cylinder on which the ink is supplied, by means of distributing rollers, from an ink roller. The ink roller is itself in contact with ink contained in an inkwell bowl. To avoid irregular printing, the quantity of ink taken up by the ink roller must be constant: for this purpose, an ink knife blade is applied against the ink roller. Two types of inkwells have long been known: inkwells with a high blade in which the blade is located above the ink roller and inkwells with a low blade in which the blade is located below the ink roller. Low blade inkwells may be preferred to high blade inkwells because of their smaller size, therefore their lower cost.

We know, in FP-A No. 1585483, an inking device of the low blade type, comprising an ink roller, an inkwell mounted on an axis parallel to the axis of the ink roller and an ink blade provided at the inside the inkwell and whose edge is applied against the ink roller. The inkwell pivots around the axis on which it is mounted in order to be able to access the various organs. But, when tilting, the inkwell moves away from the ink roller so that it is necessary to empty the inkwell and to tilt it.

On the other hand, inkwells with a low blade may include a bowl provided with several compartments, for example four, thus allowing the simultaneous printing of several pages. These compartments are generally filled with black ink but, if you want to make color prints, it is necessary to be able to change the color of the ink contained in the various compartments. You may also want a compartment to be completely emptied of its ink, if one of the four pages must remain white, for example. To change the ink of a compartment, it is necessary to empty this compartment beforehand, which has various drawbacks such as loss of time, non-recovery of the drained ink, dirty operation to be carried out.

On the other hand, as the bowls of inkwells with a high blade have the drawback of not being able to be separated into compartments, it is known to use inkwells with a high blade comprising removable bowls placed on a fixed inkwell support. The removed cuvette can thus be placed on standby with the ink it contains until it is again necessary to use it. However, if an inkwell with removable bowls is easily achievable for an inkwell of the high blade type, the same does not apply to inkwells of the low blade type in which the inkwell blade is located below the ink roller. Indeed, in this type of inkwell, the ink is held between the inkwell blade and the inkwell roller and it is not possible to remove the bowl without a large part of the ink flowing as soon as the bowl is no longer in contact with the ink roller.

The present invention therefore attempts to remedy this drawback: it aims at an inkwell of the low blade type in which it is possible to remove the cuvettes without first emptying the ink.

According to the invention, the inkwell carries at least one removable bowl, and the inkwell can pivot successively around the ink roller without the bowl deviating from said roller and around the axis on which it is mounted. so that the bowl moves away from said ink roller and thus takes up a position from which it can be easily removed.

Preferably, the inking device according to the invention is provided with means for rotating the axis of the inkwell around the axis of the roller, between two positions, a so-called working position for which the ink contained in the inkwell bowl bathes the ink roller and a position for which the end of the ink slide emerges from the ink contained in the inkwell bowl.

In a preferred embodiment of the invention, the means for fixing the bowl to the inkwell are adjustable in order to allow the permutation of different removable bowls on different inkwells.

• La fig. 1 représente le dispositif d'encrage selon l'invention en position de travail, c'est-à-dire dans une position pour laquelle l'encre contenue dans la cuvette de l'encrier baigne le rouleau encrier afin que ce dernier transmette l'encre jusqu 'au cylindre de plaque par l'intermédiaire d'autres rouleaux non représentés. Plus précisément, la fig. 1 est une coupe radiale du dispositif, effectuée au niveau d'une cuvette.
• La fig. 2 représente le dispositif d'encrage selon l'invention dans une position analogue à celle de la fig. 1, c'est-à-dire en position de travail, mais la coupe a été effectuée à l'une des deux extrémités du dispositif d'encrage, c'est-à-dire au niveau de l'un des paliers montés sur l'axe du rouleau encrier pour soutenir l'encrier.
• La fig. 3 est une figure analogue à la fig. 1 après pivotement de l'axe de l'encrier autour de l'axe du rouleau.
• La fig. 4 est une figure analogue à la fig. 3, après un pivotement supplémentaire de l'encrier autour de son axe propre, afin de dégager la cuvette du rouleau.
• La fig. 5 est une figure analogue à la fig. 4 montrant l'enlèvement ou la mise en place d'une cuvette.
• Sur toutes les figures, les éléments correspondants portent les mêmes repères.
• On se reportera tout d'abord à la fig. 1.

But in order to be better understood, the invention will now be described in a preferred embodiment, given solely by way of example and represented by the accompanying drawings.

• Fig. 1 shows the inking device according to the invention in the working position, that is to say in a position for which the ink contained in the bowl of the inkwell bathes the ink roller so that the latter transmits the ink to the plate cylinder via other rollers, not shown. More specifically, fig. 1 is a radial section of the device, carried out at the level of a bowl.
• Fig. 2 shows the inking device according to the invention in a position similar to that of FIG. 1, that is to say in the working position, but the cut was made at one of the two ends of the inking device, that is to say at one of the bearings mounted on the axis of the ink roller to support the inkwell.
• Fig. 3 is a figure similar to FIG. 1 after pivoting of the inkwell axis around the axis of the roller.
• Fig. 4 is a figure similar to FIG. 3, after an additional pivoting of the inkwell around its own axis, in order to disengage the bowl from the roller.
• Fig. 5 is a figure similar to FIG. 4 showing the removal or placement of a bowl.
• In all the figures, the corresponding elements bear the same references.
• We will firstly refer to FIG. 1.

Fig. 1 shows the ink roller 1 on which is mounted a bearing 2 integral with the axis 3 of the inkwell 4. On the inkwell 4 is fixed, by means of screws 5 and 6, a bowl 7 containing a certain amount of ink 8. The ink 8 is kept in the bowl 7 by means of the side walls 9 of the bowl, terminated by seals 10 which come to bear against the ink roller 1, on the one hand , and by an ink pad 11 whose edge is applied against the ink roller 1, on the other hand. The distance between the blade 11 and the ink roller 1 can be adjusted by means of a screw 12 fixed to the inkwell 4.

Fig. 2 shows, more clearly than FIG. 1, the fixing of the bearing 2 to a fixed frame 13 by means of a screw 14. FIG. 2 also shows the fixing of the inkwell 4 on the bearing 2 by means of a screw 15.

We will now refer to FIG. 2. This figure is similar to FIG. 1. However, it differs from the latter by the fact that, by acting on the screw 14, the bearing 2 has been separated from the frame 13, then the bearing has been pivoted until it comes to hang, by means of a clip 16, to a dowel 17, also fixed to the fixed frame 13. A jack 18, one end of which is fixed to the bearing 2 and the other end to the fixed frame 13, has made it possible to perform this pivoting of the bearing 2 around the axis of the roller 1. In this pivoting movement, the bowl 7 of the inkwell 4 remained in contact with the roller 1, thus preventing the ink 8 from escaping from the bowl 7. In the position of fig. 3, the end of the ink slide 11 emerges from the ink 8 contained in the bowl 7.

We will now refer to FIG. 4 which shows the pivoting of the inkwell 4 about its axis 3, the latter now remaining fixed since the bearing 2 has been hooked to the fixed frame 13 by means of the clip 16. In order to allow the inkwell 4 to pivot around its axis 3, of course, the inkwell 4 was removed from the bearing 2 by unscrewing the screw 15. In the position obtained after pivoting around the axis 3, the inkwell 4 is such that the bowl 7 moves away from the roller 1 and thus assume a position for which it can be easily removed, since the roller 1 is no longer necessary for maintaining the ink 8 in the bowl 7. In this position, the blade 11 can also be easily cleaned.

The removal of the bowl 7 is shown in FIG. 5. This is done very simply, once we have separated the bowl 7 from the inkwell 4 by completely unscrewing the screw 5. We can thus remove the bowl 7 and replace it with another similar bowl containing a different color ink. The new bowl which will replace bowl 7 may be of slightly different dimensions from the first; this is why provision has been made for precise positioning of the bowl 7 on the inkwell 4 by a double adjustment carried out by means of the screws 6 and 19. This adjustment does not have to be carried out each time that a bowl 7 on an inkwell 4. Indeed, the adjustment of the screw 6 is carried out once and for all on each bowl 7 so that the distance between the end of the blade 11 and the bearing face of the screw 6 is identical for all the bowls 7, and the adjustment of the screw 19 is carried out once and for all on each inkwell 4 so that the distance between the roller 1 and the bearing face of the screw 19 is identical for all the inkwells 4. When placing any bowl 7 on any inkwell 4, already adjusted, it suffices to screw the screw 6 into the screw 19 without it being necessary to carry out a new adjustment. The fixing of the bowl 7 on the inkwell 4 ends of course by the screwing of the screw 5.

The invention which has just been described has numerous advantages. It makes it easy to change the bowls of the inkwell of an inking device of the low blade type, without requiring any adjustment each time the bowl is changed. It also makes it easy to clean the ink slide.

The number of cuvettes supported by the inkwell can obviously be arbitrary, this number depending on the number of pages that it is desired to print simultaneously.

Claims (3)

1. A low-blade-type inking mechanism comprising an ink duct roller (1), an ink duct (4) mounted on an axis (3) parallel to the axis of the ink duct roller (1) and a low blade (11) provided inside the ink duct (4), the edge of which is applied against the ink duct roller (1), characterized in that the ink duct (4) brings at least one removable trough (7) and in that the ink duct (4) can, on the one hand, pivot about the ink duct roller (1) without the trough (7) moving away from said roller (1) and about the axis (3) so that the trough moves away from said ink duct roller (1) and takes a position in which it is able to be easily removed.

2. A low-blade-type inking mechanism as claimed in Claim 1, characterized in that it is equipped with means (18) to rotate the axis (3) of the ink duct (4) about the axis of the roller (1) between two positions, a so-called work position in which the ink (8) contained in the trough (7) of the ink duct (4) wets the ink duct roller (1 ) (Fig. 1 ) and a position in which the end of the ink duct blade (11) emerges from the ink (8) contained in the trough (7) (fig. 3).

3. A low-blade-type inking mechanism as claimed in either of Claims 1 or 2, characterized in that the means (6 and 19) of fixing the trough (7) to the ink duct (4) are adjustable to permit the permutation of different detachable troughs (7) to different ink ducts (4).

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