GB2033301A

GB2033301A - Inking apparatus

Info

Publication number: GB2033301A
Application number: GB7937023A
Authority: GB
Original assignee: Polygraph Leipzig Kombinat Veb
Current assignee: Polygraph Leipzig Kombinat Veb
Priority date: 1978-10-28
Filing date: 1979-10-25
Publication date: 1980-05-21
Also published as: SE7908845L; FR2439672A1; DE2935033C2; GB2033301B; DE2935033A1; DD140440A1

Abstract

The invention concerns an inking apparatus for printing machines, in which ink metering takes place by an ink well (1), a doctor blade (3) and following inking rollers (6,7). It is an aim of invention to shorten the time between resetting of the doctor blade (3) and inking adjustments becoming effective at the application rollers. This is attained by increasing automatically or on manual command the peripheral speed of the ductor roller (5) through an angle alpha between the contact points of the ductor roller (5) with the doctor blade (3) and the ductor roller (5) with the first inking roller (5). <IMAGE>

Description

SPECIFICATION An inking apparatus The present invention relates to an inking apparatus for a printing machine.

A demand is made on inking apparatuses of modern printing machines that during the settingup of the inking apparatus from the instant of resetting the doctor blade screws at the ink well until the application rollers become effective, the number of the machine cycles occurring is as small as possible.

DE-PS 2 225 571 discloses an apparatus in which the ink taken off by the ductor is transferred to an inking roller, the contact pressure of which against the ductor and a further inking roller can be varied by setting means during the running of the machine. The speed of the ductor roller is not regulable.

This inking apparatus provides a through preliminary distribution through the settable ink squeezing. It is however disadvantageous that due to the ductor speed being greatly reduced relative to the machine speed, a relatively long time passes before the ink strip delivered by the ductor has reached the film roller. This acts particularly disadvantageously during variation of the doctor blade setting. Although attempts have been made to reduce this disadvantage in keeping the spacing of the contact points at the periphery of the ductor between doctor blade and film roller as small as possible, this measure however has the disadvantage that the ink possibly dripping from the ink well impinges on the film roller and the ink metering is thereby disturbed.

According to the present invention there is provided an inking apparatus for a printing machine, comprising a ductor roller, a doctor blade settable relative to a first region of the peripheral path of the ductor roller, a roller arranged to engage the ductor roller at a second region of the periphal path of the ductor roller, and selectably actuable means to increase the rotational velocity of the ductor roller during an angle of rotation thereof corresponding to the angle of travel of the ductor roller from the first to the second region.

The roller arranged to engage the ductor roller may be an inking roller, the apparatus further comprising a further roller arranged to engage the inking roller and means to disengage the inking roller from at least one of the ductor roller and the further roller during said increases in rotational velocity.

The roller arranged to engage the ductor roller may be a vibrator roller, the apparatus further comprising an inking roller arranged to engage the vibrator roller and means to so vibrate the vibrator roller between the ductor roller and the inking roller that the period of said increase in rotational velocity falls within the period during which the vibratory roller is disengaged from at least one of the ductor roller and the inking roller.

The selectably actuable means may be manuably actuable.

The selectably actuabie means may be automatically actuable by program means.

Embodiments of the present invention will now be more particularly described by way of example and with reference to the accompanying drawing in which Fig. 1 shows schematically a part of a film inking apparatus, and Fig. 2 shows a schematically a part of a vibrator inking appartus.

Fig. 1 shows an apparatus in which ink 2 in an ink well 1 is metered by means of doctor blade screws 4 through a doctor blade 3 onto the surface of a ductor roller 5. The ink 2 is then transferred from the ductor roller 5 to a first inking roller 6 and from there to an inking roller 7. The ink passes through inking and distributor rollers (not shown) onto application rollers (also not shown).

The ductor roller 5 is driven through an electrical motor 8. The rotational speed of the motor 8 is greatly reduced by a gear comprising worm 10, which is fastened on a shaft 9 of the electrical motor 8 and which is constantly in engagement with a worm wheel 12 disposed on a ductor shaft 11. Further, variable, reduction of the rotational speed is attained through electrically influencing the electrical motor 8.

Regarding Fig. 1, after variation of the ink metering by means of the doctor blade screws 4, the first inking roller 6 triggered manually pivots away from the ductor roller 5 and/or from the inking roller 7. In this time, the ductor roller 5 is accelerated for a short time through an angle a by bridging-over of the electrical regulating magnitudes. Immediately thereafter, the inking roller 6 pivots back into its original position.

Thereby, the changed ink metering has very rapidly become effective on the inking roller 7 which rotates at the machine speed.

Fig. 2 shows an inking apparatus comprising a vibrator roller 13. After the vibrator roller 13 has moved away from the ductor roller 5, the acceleration of the ductor roller 5 through the angle a takes place. This process is terminated before reaching the inking roller 7. In that case, it is insignificant whether the pivot point of the vibrator is arranged in the centre of the inking roller 7 or externally of this centre.

1. An inking apparatus for a printing machine, comprising a ductor roller, a doctor blade settable relative to a first region of the peripheral path of the ductor roller, a roller arragned to engage the ductor roller at a second region of the periphal path of the ductor roller, and selectably actuable means to increase the rotational velocity of the ductor roller during an angle of rotation thereof corresponding to the angle of travel of the ductor roller from the first to the second region.

2. An apparatus as claimed in claim 1, wherein the roller arranged to engage the ductor roller is an inking roller, the apparatus further comprising a further roller arranged to engage the inking roller

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION An inking apparatus The present invention relates to an inking apparatus for a printing machine. A demand is made on inking apparatuses of modern printing machines that during the settingup of the inking apparatus from the instant of resetting the doctor blade screws at the ink well until the application rollers become effective, the number of the machine cycles occurring is as small as possible. DE-PS 2 225 571 discloses an apparatus in which the ink taken off by the ductor is transferred to an inking roller, the contact pressure of which against the ductor and a further inking roller can be varied by setting means during the running of the machine. The speed of the ductor roller is not regulable. This inking apparatus provides a through preliminary distribution through the settable ink squeezing. It is however disadvantageous that due to the ductor speed being greatly reduced relative to the machine speed, a relatively long time passes before the ink strip delivered by the ductor has reached the film roller. This acts particularly disadvantageously during variation of the doctor blade setting. Although attempts have been made to reduce this disadvantage in keeping the spacing of the contact points at the periphery of the ductor between doctor blade and film roller as small as possible, this measure however has the disadvantage that the ink possibly dripping from the ink well impinges on the film roller and the ink metering is thereby disturbed. According to the present invention there is provided an inking apparatus for a printing machine, comprising a ductor roller, a doctor blade settable relative to a first region of the peripheral path of the ductor roller, a roller arranged to engage the ductor roller at a second region of the periphal path of the ductor roller, and selectably actuable means to increase the rotational velocity of the ductor roller during an angle of rotation thereof corresponding to the angle of travel of the ductor roller from the first to the second region. The roller arranged to engage the ductor roller may be an inking roller, the apparatus further comprising a further roller arranged to engage the inking roller and means to disengage the inking roller from at least one of the ductor roller and the further roller during said increases in rotational velocity. The roller arranged to engage the ductor roller may be a vibrator roller, the apparatus further comprising an inking roller arranged to engage the vibrator roller and means to so vibrate the vibrator roller between the ductor roller and the inking roller that the period of said increase in rotational velocity falls within the period during which the vibratory roller is disengaged from at least one of the ductor roller and the inking roller. The selectably actuable means may be manuably actuable. The selectably actuabie means may be automatically actuable by program means. Embodiments of the present invention will now be more particularly described by way of example and with reference to the accompanying drawing in which Fig. 1 shows schematically a part of a film inking apparatus, and Fig. 2 shows a schematically a part of a vibrator inking appartus. Fig. 1 shows an apparatus in which ink 2 in an ink well 1 is metered by means of doctor blade screws 4 through a doctor blade 3 onto the surface of a ductor roller 5. The ink 2 is then transferred from the ductor roller 5 to a first inking roller 6 and from there to an inking roller 7. The ink passes through inking and distributor rollers (not shown) onto application rollers (also not shown). The ductor roller 5 is driven through an electrical motor 8. The rotational speed of the motor 8 is greatly reduced by a gear comprising worm 10, which is fastened on a shaft 9 of the electrical motor 8 and which is constantly in engagement with a worm wheel 12 disposed on a ductor shaft 11. Further, variable, reduction of the rotational speed is attained through electrically influencing the electrical motor 8. Regarding Fig. 1, after variation of the ink metering by means of the doctor blade screws 4, the first inking roller 6 triggered manually pivots away from the ductor roller 5 and/or from the inking roller 7. In this time, the ductor roller 5 is accelerated for a short time through an angle a by bridging-over of the electrical regulating magnitudes. Immediately thereafter, the inking roller 6 pivots back into its original position. Thereby, the changed ink metering has very rapidly become effective on the inking roller 7 which rotates at the machine speed. Fig. 2 shows an inking apparatus comprising a vibrator roller 13. After the vibrator roller 13 has moved away from the ductor roller 5, the acceleration of the ductor roller 5 through the angle a takes place. This process is terminated before reaching the inking roller 7. In that case, it is insignificant whether the pivot point of the vibrator is arranged in the centre of the inking roller 7 or externally of this centre. CLAIMS

2. An apparatus as claimed in claim 1, wherein the roller arranged to engage the ductor roller is an inking roller, the apparatus further comprising a further roller arranged to engage the inking roller and means to disengage the inking roller from at least one of the ductor roller and the further roller during said increase to rotational velocity.

3. An apparatus as claimed in claim 1, wherein the roller arranged to engage the ductor roller is a vibrator roller, the apparatus further comprising an inking roller arranged to engage the vibrator roller and means to so vibrate the vibrator roller between the ductor roller and the inking roller that the period of said increase in rotational velocity falls within the period during which the vibrator roller is disengaged from at least one of the ductor roller at the inking roller.

4. An apparatus as claimed in any one of the preceding claims, wherein the selectably actuable means are manually actuable.

5. An apparatus as claimed in any one of the preceding claims, wherein the selectably actuable means are automatically actuable by program means.

6. An inking apparatus substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawing.

7. An inking apparatus substantially as hereinbefore described with reference to Fig. 2 of the accompanying drawing.