JPH0623962A - Ink ductor driver in printing press - Google Patents

Abstract

PURPOSE: To provide a ductor roller drive device wherein when a ductor roller comes into contact with an ink distributing roller, an impact is not produced on the ductor roller. CONSTITUTION: A transmission device is provided between a slowly rotating ink fountain roller 3 and a faster rotating ink distributing roller 4 for cyclic adjustment of the circumferential speeds of a ductor roller 1 pivotable forth and back in accordance with the work cycle of the machine to the different curcumferential speeds of the roller 3 and the roller 4. In order to accelerate the roller 1 when the roller 1 pivots toward the roller 4, a drive device controllable in accordance with the work cycle of the machine is provided, which machine is connected to the roller 1 by the differential transmission device to accelerate the circumferential speeds of the roller 1 to the circumferential speeds of the roller 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink transfer roller driving device for a printing machine according to the preamble of the claims.

[0002]

Ink transfer rollers are commonly used in inking units of printing presses, especially sheet-fed rotary offset presses.

Usually, the ink transfer roller is rotatably supported by a swiveling lever, and includes a slowly rotating inking roller and a first ink kneading roller of an inking device which rotates significantly faster than this. It is possible to turn between. Therefore, the ink taken out from the inking roller is supplied to the ink kneading roller, in which case, after the ink transfer roller comes into contact with the inking roller and the ink kneading roller, they are carried together by friction, and therefore the machine cycle At the time of contact with the ink kneading roller, it is remarkably accelerated, and at the time of contact with the ink discharge roller, it is remarkably decelerated.

German Patent 26 10 12
From publication No. 6, the ink transfer roller is periodically and alternately connected by means of two wheel trains and two magnetic couplings with the ink kneading roller or the ink discharging roller, and the ink transferring roller comes into contact with the ink mixing roller or the ink discharging roller. It is known to drive each of them at the same rotational speed. As a result, the contact of the rollers is made at the same peripheral speed, and thus the scraping edge (Schabekante) at the time of ink feeding, the peripheral speed of the rollers in contact is different, and the ink is scraped off irregularly. Irregular patterns caused by unevenness are avoided.

In the case of the device described in US Pat. No. 3,688,696, the same purpose should be achieved by a belt drive in which the ink transfer rollers are associated with a controllable electric motor. However, this device does not provide reliable operation at the high printing speeds of modern printing presses.

German Patent No. 29 44 82
According to Japanese Patent Laid-Open No. 3 (1994), the peripheral speed of the ink transfer roller is periodically accelerated and decelerated, so that when the ink transfer roller turns toward the ink kneading roller, the ink transfer roller accelerates and when it turns toward the ink delivery roller. It is known to couple the spring load, which slows the ink transfer roller, to the ink transfer roller by means of a planetary gear.

Federal Republic of Germany Patent Application Publication No. 300
According to Japanese Laid-Open Patent Publication No. 2592, a similar action for preventing a rubbing edge during ink feeding is achieved by periodically coupling an ink transfer roller to a vibrating body using a transmission device having various gear ratios. To be done. However, in both of these cases, the cost to prevent rubbing edges during ink feeding is high.

The present invention, on the other hand, pursues other objectives. Conventionally, noise has increased as the printing speed has increased. As a result of research, the so-called ink transfer roller impact in an inking unit of a printing machine of the type described at the beginning, which has an ink transfer roller between a slowly rotating inking roller and a significantly faster inking roller. The generation of noise is mainly due to the high acceleration acting on the ink transfer roller when the transfer roller comes into contact with the ink kneading roller, and is therefore practically increased in a shock-like manner based on the machine speed.

[0009]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ink transfer roller driving device for accelerating the peripheral speed of the ink transfer roller to the magnitude of the peripheral speed of the ink mixing roller in the turning path toward the ink mixing roller. Is to configure.

[0010]

This object is achieved by the features of the characterizing part of claim 1.

The basic advantage over the known arrangements is that the ink transfer roller is already accelerated to the peripheral speed of the ink mixing roller by means of a special motor drive on the swirl path from the ink delivery roller to the ink mixing roller. Is to be done. In that case, since both rollers rotate at substantially the same peripheral speed, the acceleration of the ink transfer roller, which is the main cause of the ink transfer roller impact, is not performed. Since the ink transfer roller is always connected to the drive motor via the differential transmission, the internal friction of the differential transmission and the drive motor will be reduced after the ink transfer roller changes direction from the ink kneading roller to the ink delivery roller. Thus, the peripheral speed of the ink transfer roller is reduced. Therefore, the ink transfer roller is actually decelerated again to the peripheral speed of the ink transfer roller when traveling toward the ink transfer roller. However, this must not preclude that in some cases a control device for performing the same drive can be provided as a differential transmission for deceleration.

In a particularly preferred arrangement, an electric drive for the ink transfer rollers is provided, which is controlled by the operating cycle of the machine and which is provided by a differential transmission having a gear ratio which varies during rotation. Is combined with. Suitable are compact and space-saving type harmonic drive type differential transmissions known in the printing machine industry, but also other conventional differential transmissions such as cam transmissions, coupling transmissions, etc. Are suitable. Furthermore, the use of a harmonic drive transmission has the advantage that such a transmission can be adjusted in some cases and therefore the acceleration of the ink transfer roller in the swirl path towards the ink kneading roller can be optimally adjusted. ing.

[0013]

The invention is shown diagrammatically in the drawing.

The ink transfer roller 1 of the inking unit of the printing unit 2 is pivotably mounted between the inking roller 3 and the first inking unit 4 of the inking unit. Both ends of the shaft of the ink transfer roller 1 are rotatably supported by a crank 5, and one end of the shaft has a bearing 6 fixed to the frame. It is possible to swivel about the axis of this bearing 6 between the installation and the installation of the ink kneading roller 4.

The drive unit for the ink transfer roller 1 comprises an electric motor 7 which can be driven periodically, the shaft of which is connected to the shaft 9 of the ink transfer roller 1 via a differential transmission 8. By cyclically driving the electric motor 7, the electric motor 7 acts on the shaft 9 of the ink transfer roller 1 via the differential transmission device 8 to move the ink transfer roller 1 from the ink delivery roller 3 to the ink kneading roller 4. Accelerate with the turning circuit. In that case, when the ink transfer roller 1 travels toward the ink kneading roller 4, the acceleration is adjusted by a commercially available differential transmission device so that the ink transfer roller 1 reaches almost the same peripheral speed as the ink kneading roller. Ink transfer roller impacts no longer occur. When the ink transfer roller 1 periodically returns to the ink discharge roller 3 to perform the turning operation, the drive motor 7 is disconnected. At that time, a freewheel provided between the differential transmission device 8 and the shaft 9 of the ink transfer roller 1 acts, and in some cases, the braking of the ink transfer roller 1 is simultaneously performed by friction force. Therefore, the peripheral speed of the ink transfer roller 1 can be adjusted to the peripheral speed of the ink discharge roller 3. In some cases, deceleration of the inking roller in its turning circuit towards the inking roller is also achieved by the same drive, but this is generally regarded as an unnecessary, optional means. In the case of the differential transmission according to the embodiment shown in FIG. 4, the electric motor 7 is driven by the harmonic drive transmission (Harmonic-Drive-Getriebe) 12 via the pinion 10.
Drive its input 11 and its output 13 drives a gear 14 which can be connected to the shaft 9 of the ink transfer roller 1, for example via a freewheel. The gear ratio between the input part 11 and the output part 13 is defined by a main shaft drive generator 16 which is made up of two parts coupled to each other and which can be adjusted externally by a shaft 15. Such harmonic drive transmissions are commercially available and are not the subject of the present invention.

FIG. 5 schematically shows the differential cam transmission in different positions. This transmission is also suitable for obtaining the desired acceleration of the ink transfer roller 1. The drive pin 18 is attached to the disk 17 that can be driven by the drive motor 7.
The drive pin 18 is suitable for fitting in the groove 19 of the second disc 20 which can be connected to the shaft 9 of the ink transfer roller 1 via a freewheel or the like. Both discs 17 and 20 are provided with teeth in their arcuate area, which teeth bite against each other only when the drive pin 18 of one disc leaves the groove 19 of the other disc. Fit. Acceleration and deceleration of the groove provided with the disc takes place on the path of the drive pin 18 through the groove 19.
When the arcuate teeth of both discs 17 and 20 are engaged, torque is transmitted at a constant gear ratio. Figure 5
The differential cam transmission corresponding to the above can be designed for both angular acceleration and angular deceleration. This type of cam transmission is state of the art and is not the subject of the present invention.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an inking device of a printing unit including an ink transfer roller provided so as to be rotatable.

FIG. 2 is a side view of an ink discharge roller, an ink transfer roller, and an ink kneading roller that are enlarged on a scale proportional to FIG.

FIG. 3 is a plan view of driving ends of an ink transfer roller, an ink discharge roller, and an ink kneading roller.

FIG. 4 is a schematic representation of a suitable differential transmission.

FIG. 5 is a differential cam transmission in different drives.

[Explanation of symbols]

 1 Ink Transfer Roller 2 Printing Unit 3 Inking Roller 4 Ink Mixing Roller 5 Crank 6 Bearing 6 Electric Motor 8 Differential Transmission 9 Ink Transfer Roller Shaft 10 Pinion 11 Input 12 Harmonic Drive Transmission 13 Output 14 Gear 15 Shaft 16 Axial drive generator 17 Disc 18 Drive pin 19 Groove 20 Disc

Claims (4)

[Claims] 1. An ink transfer roller supported on at least one crank reciprocates in a machine operation cycle between a slow rotating inking roller and a faster rotating swaying roller, In an ink transfer roller driving device of a printing machine, which is provided with a transmission device for periodically adjusting the peripheral speed of the transfer roller to different peripheral speeds of the ink feeding roller and the ink kneading roller, the ink transfer roller (1) is A drive unit (7) controllable in the operating cycle of the machine at the beginning of the swiveling movement, the ink transfer roller being a differential which accelerates the ink transfer roller (1) to the peripheral speed of the ink kneading roller (4) Ink transfer roller drive of a printing press, characterized in that it is connected to the drive (7) by a transmission (8 or 7 to 20). 2. The ink transfer roller (1) comprises an electric drive (7), which is electrically controllable in the operating cycle of the machine and which has a variable transmission ratio during rotation. 2. Ink transfer roller drive according to claim 1, which is associated with the ink transfer roller (1) by means of a differential transmission (8) having. 3. Ink transfer roller drive according to claim 1, wherein the ink transfer roller (1) comprises an electric motor, a differential cam transmission and, considerably, a drive which operates cyclically in the operating cycle of the machine. 4. An adjustable differential transmission (8), in particular a harmonic drive transmission (1), having a continuously variable transmission ratio.
The ink transfer roller driving device according to claim 1, further comprising 2).