EP0031003A2 - Drive with power branching for a multicolour rotary printing machine - Google Patents

Abstract

1. Driving system for multi-colour rotary printing machines having printing units (1 to 6) disposed in tandem arrangement, said printing units being connected to one another via a gear train (22) and being driven via two power input locations (21, 36), each of which is fed via a supplying path (8, 9) by a common motor (7) with a variable, speed-dependent power, and whereby a supplying path is provided with a coupling (12), wherein the coupling (12) is designed as a hydrodynamic coupling and connected to the supplying path (9) having a power increasing with the cube of the speed and feeding the second power input location (36, 38), in such a way that the coupling primary part (11) assigned to the driving motor (7) revolves more rapidly than does the coupling secondary part (30) assigned to the second power input location (36, 38), whereby a constant rotary speed ratio is maintained therebetween and the power increase of the supplying path (9) feeding the second power input location (36, 38) is proportional to the power decrease of the supplying path (8) feeding the first power input location (21, 37).

Description

The invention relates to a drive with power split for multi-color rotary printing presses with a series arrangement of the printing units, which are connected to one another via a gear train and are driven by two force input points, which are fed with power starting from a common motor via a supply line.

It is known to feed multicolor offset printing machines, the printing units of which are in drive connection with one another, at one or more points with the required drive power. Is z. B. a six-color machine driven from the center, so more power must be transmitted via the closest to the force input point power transmission than that arranged at the ends of the machine. This leads to different phase positions of the printing units occurring as a result of the different deformations of the drive members participating in the power transmission. These different deformations can lead to printing difficulties such as e.g. B. offset at different speeds, and thus result in a reduced print quality.

In order to avoid this disadvantage, it has been proposed to supply a multi-color offset printing machine with drive power from several locations, which results in a more favorable load distribution. So it is z. B. conceivable that the drive power between the printing units 2 and 3 and the printing units 4 and 5 is supplied in a six-color machine. In these cases, the pressure on the printing units closest to the feed points is not as high as in the previously dealt with drive. The deformations are less, which results in better print quality. However, this type of power feed sets ahead that the metering of the power components is carried out according to the load on the individual printing units of the machine. It is inadmissible that a tooth engagement ensuring the sheet transfer z. B. between the printing units 3 and 4 is relieved of driving forces or loaded alternately, so that an unstable state arises. This occurs flank change of the gears of the gear train with the associated known disadvantages, for. B. Duplicate.

From DE-PS 1 237 140 it is known to divide the power flow through the entire machine onto the individual drive groups in a certain ratio to one another by using power-dividing differentials in front of the feed points, so that the flank system of all spur gears of the gear train is secured. However, this type of branching of power presupposes that the power requirement of the individual printing units is always known, regardless of which printing speed is used and what type of printing work is. However, as soon as the power requirements of the individual printing units change in relation to one another, a change in the direction of the power flow between the individual printing units and thus an adverse edge change is also possible, since the power division caused by the differentials remains constant.

The object of the invention is, with a minimum of effort, both in terms of means and costs, to completely rule out overdetermination of the drive and to continuously adapt the power feed into the two force input points of the gear train to the varying power requirements of the individual printing units, in order to achieve one Flank change of the gears of the gear train to ver avoid.

The solution to the problem according to the invention is first of all the knowledge that the load on the printing press is strongly dependent on its speed. The numerous non-uniform gear ratios, cam-controlled gripper drives, etc., available on a sheet-fed offset printing machine, load the main drive with a torque that increases quadratically with the speed. Naturally, these dynamic additional forces are not available at speed 0. When starting up or at very low printing speeds, the drive only has to cover the friction losses. This means that, at low speeds, the disadvantage of the prior art drives of the excessive load on the printing units closest to the feed point is not so significant. This disadvantage is only noticeable in print quality at higher printing speeds, especially since the inking units require more power as the speed increases.

The invention makes use of this knowledge, starting from the torque demand characteristic of the printing press, in the fulfillment of its task, the solution of which is that the supply line feeding the second force input point leads to cubic increasing power with the speed. This measure, which is easy to carry out, ensures that the power share of the supply line feeding the second force input point increases to the same extent as the share of the power of the supply line assigned to the first force input point falls, as a result of which the power supply to the individual printing units is as uniform as possible and results therefrom constant printing quality is ensured.

In an advantageous embodiment of the invention, a hydrodynamic coupling is switched into the supply line that feeds the second force input point. By appropriate selection of the coupling with regard to dimensioning, speed and slip, it is possible to ensure that the load on the printing units remains approximately constant over the entire speed range, so that excessive loading of individual printing units cannot occur and harmful flank changes are avoided or instead, even individual printing units would have to be oversized.

So that the power flow is clear, in a further development of the inventive concept, the primary part and the secondary part of the hydrodynamic coupling are in driving connection with one another in such a way that there is a constant speed ratio between the two, the primary part rotating faster than the secondary part facing the force input point.

In order to vary the clutch slip from positive values above zero to negative values, a continuously variable transmission is engaged in the second supply line between the hydrodynamic clutch and the second force input point. As a result, the amount of power flowing through the coupling can be changed in such a way that numerous variations between power sharing and reactive power (bracing) are possible.

• Fig. 1 eine schematische Darstellung einer ersten Ausführungsform eines leistungsverzweigten Antriebes nach der Erfindung mit eingeschalteter hydrodynamischer Kupplung für eine Sechsfarben-Bogenrotationsdruckmaschine mit Krafteingabe zwischen dem zweiten und dritten sowie dem vierten und fünften Druckwerk,
• Fig. 2 eine schematische Draufsicht auf den Antrieb gemäß Fig. auszugsweise über den Bereich der beiden Krafteingabestellen,
• Fig. 3 ein Diagramm, das den Leistungsbedarf der beiden Versorgungsstränge einer mit einem Antrieb nach der Erfindung ausgestatteten Mehrfarben-Rotationsdruckmaschine bei steigender Maschinendrehzahl aufzeigt,
• Fig. 4 ein Diagramm, das den Drehmomentenbedarf der einzelnen Druckwerke in einem Antrieb gemäß Fig. 1 bei steigender Maschinendrehzahl aufzeigt,
• Fig. 5 die gleiche Ansicht wie in Fig. 1 mit schematischer dargestellter Aufteilung der Gesamtantriebsleistung und Belastung der einzelnen Druckwerke,
• Fig. 6 die gleiche Ansicht wie in Fig. 1 jedoch mit Krafteingabe vor dem ersten und zwischen dem dritten und vierten Druckwerk,
• Fig. 7 dasselbe Diagramm wie in Fig. 4 jedoch für einen Antrieb gemäß Fig. 6,
• Fig. 8 eine schematische Darstellung eines Antriebes gemäß Fig. 1 mit einem in den zweiten Versorgungsstrang eingeschalteten stufenlosen Getriebe.

The invention is described below with reference to three exemplary embodiments shown in the drawings. It shows:

• Fig. 1 is a schematic representation of a first embodiment form of a power-split drive according to the invention with the hydrodynamic clutch switched on for a six-color sheet-fed rotary printing press with force input between the second and third and the fourth and fifth printing units,
• 2 shows a schematic top view of the drive according to FIG. Excerpt over the area of the two force input points,
• 3 shows a diagram which shows the power requirement of the two supply lines of a multi-color rotary printing press equipped with a drive according to the invention with increasing machine speed,
• 4 is a diagram showing the torque requirement of the individual printing units in a drive according to FIG. 1 with increasing machine speed,
• 5 shows the same view as in FIG. 1 with a schematically illustrated distribution of the total drive power and load of the individual printing units,
• 6 shows the same view as in FIG. 1 but with force input in front of the first and between the third and fourth printing units,
• 7 shows the same diagram as in FIG. 4 but for a drive according to FIG. 6,
• 8 shows a schematic illustration of a drive according to FIG. 1 with a continuously variable transmission switched into the second supply line.

Figures 1, 2, 4 and 6 show a six-color sheet-fed rotary printing machine, the six printing units 1-6 of which are arranged in series.

The drive power required for the six printing units 1-6 is applied by a drive motor 7, which is designed, for example, as an electric motor. The power supply of the six printing units 1-6 takes place via two separate supply lines 8 and 9, which are fed with power by the common drive motor 7 at the same time.

In a first exemplary embodiment of the invention according to FIGS. 1 and 2, a coupling primary part 11 of a hydrodynamic coupling 12 is arranged on the end of a drive shaft 10 of the drive motor 7. The first supply line 8 branches off in front of the primary coupling part 11, in which the greater part of the drive power generated by the drive motor 7 is first transmitted to a belt drive 14. A V-belt pulley 15 of the belt drive 14 drives a spur gear pair 17 via a shaft 16, one spur gear of which is attached to the free end of a journal 19 of a transfer cylinder, not shown and described in more detail, arranged between the second and third printing units. The first supply line 8 opens at one of the above. Axle journal 19 fastened drive gear 20 into a first force input point 21 of a gear train 22.

The further spur gears of the gear train 22 shown in extracts in FIG. 2 are identified from right to left with the reference numbers 24-29.

The smaller residual portion of the drive power applied by the common drive motor 7, which is not transmitted in the first supply line 8, is fed into the second supply line 9.

In this second supply line 9, the above-mentioned hydrodynamic clutch 12 is switched on in such a way that there is a constant speed ratio between the clutch primary part 11 arranged on the engine side and a clutch secondary part 30 downstream thereof. The primary coupling part 11 has a slightly higher speed than the secondary coupling part 30, so that there is always a constant slip between these two coupling parts 11 and 30.

The clutch secondary part 30 transmits the drive power to a belt drive 31, the V-belt pulley 32 of which drives a spur gear tooth pair 34 via a shaft 33, one of the spur gear wheels 34 being fastened at the end to an axle journal 35 of a transfer cylinder, not shown or described. The second supply line 9 opens between the printing unit 4 and 5 in the drive gear 29 for the transfer cylinder mentioned above into a second force input point 36 in the gear train 22. The drive gear 29 is also fastened to the journal 35 and is in the gear train 22 with the adjacent drive gear 28 of the Printing cylinder of the fourth printing unit 4, not shown, engages.

• Der Antriebsmotor 7 treibt über die beiden Versorgungsstränge 8 und 9 die Druckmaschine an. In den zweiten Versorgungsstrang 9 ist die hydrodynamische Kupplung 12 eingeschaltet. Hierbei ist das Kupplungsprimärteil 11 der Antriebsseite, das Kupplungssekundärteil 30 der Maschinenseite zugewandt. Zwischen dem Kupplungssekundärteil 30 der hydrodynamischen Kupplung 12 und deren Kupplungsprimärteil 11 besteht eine starre Verbindung über die Knoten 21 und 36, welche als erste und zweite Krafteingabestellen fungieren und über den Verbindungsstrang 40 zwischen diesen beiden. Die Stirnräderpaare 17 bzw. 34 oder die Riementriebe 14 bzw. 31 sind so bemessen, daß zwischen dem Kupplungssekundärteil 30 und dem Kupplungsprimärteil 11 ein konstantes Drehzahlverhältnis besteht,derart, daß ein Zwangsschlupf der hydrodynamischen Kupplung 12 vorliegt. Hierbei ist die Drehzahl des Kupplungssekundärteils 30 kleiner als die des Kupplungsprimärteils 11. Das Übersetzungsverhältnis im Verbindungsstrang 40 beträgt 1:1 entsprechend seiner Aufgabe der drehwinkelgetreuen Kupplung der Druckwerke untereinander.

The drive described above works as follows:

• The drive motor 7 drives the printing press via the two supply lines 8 and 9. The hydrodynamic clutch 12 is switched on in the second supply line 9. Here, the clutch primary part 11 faces the drive side, the clutch secondary part 30 faces the machine side. There is a rigid connection between the clutch secondary part 30 of the hydrodynamic clutch 12 and its clutch primary part 11 the nodes 21 and 36, which act as first and second force input points and via the connecting line 40 between these two. The pairs of spur gears 17 and 34 or the belt drives 14 and 31 are dimensioned such that there is a constant speed ratio between the clutch secondary part 30 and the clutch primary part 11 such that there is a forced slip of the hydrodynamic clutch 12. Here, the speed of the clutch secondary part 30 is lower than that of the clutch primary part 11. The transmission ratio in the connecting line 40 is 1: 1 in accordance with its function of the rotation angle-accurate coupling of the printing units to one another.

The total output required by the printing press is represented in a diagram in FIG. 3 by curve "a" in a standardized representation depending on the machine speed n. The power P increases with increasing machine speed n. The abscissa of this graph represents thereby the speed ratio n D / n D _max relative to the Ma ^s chinendrehzahl n D _max, the ordinate the power ratio P / P _max based on the maximum power P _max. The curve "a" represents the total performance of the machine and thus the power to be applied by the drive motor 7.

The curve "b" indicates the proportion of the power ratio P _h y _{dr /} P _max that is fed to the machine via the second supply line 9. Corresponding to the cubic dependence of the power on the speed in turbomachines, to which the hydrodynamic coupling 12 is also to be assigned, the curve "b" is a cubic parabola.

4 shows the torque requirement of the individual printing units 1 - 6 of a six-color sheet-fed rotary printing press in Dependence on the speed n when using a drive according to the first embodiment again; the standardized representation is also used here. It is assumed that friction resistances have to be overcome when starting the machine at the speed 0, assuming that the starting torque is e.g. B. is half of the maximum torque at maximum machine speed.

The curve "c" thus shows the total torque requirement on the machine. The curve "d" corresponds to the torque that is supplied by the drive motor 7 via the hydrodynamic clutch 12. It is a square parabola. The diagram also shows the torque requirements M _D1 to M _D6 for the individual printing units 1-6.

It can be seen that at low speeds the torque requirement of the entire machine is primarily covered by the first supply line 8 (M _mech ), while with increasing machine speed the second supply line 9 leads increasingly more torque (M _h y _dr ). The mechanical portion M _mech and the hydraulic portion M _h y _{dr of} the torque are highlighted by corresponding arrows plotted in the ordinate direction in the diagram in FIG. 4. At the maximum speed of the machine corresponding to the abscissa value 1, it can be seen from FIG. 4 that the torque requirement of the printing unit 6 is completely covered and that of the printing unit 5 is covered up to half by the second supply line 9 (M _h y _dr ).

Assuming that each printing unit has the same torque requirement, but for the sake of simplicity, this fundamental view of the investors and the delivery arms is said to be without performance are taken, the torque distribution numerically indicated in FIG. 5 results at the maximum speed of the machine. The torque requirement for an individual printing unit is numerically set to 1, so that the drive motor 7 has to apply the total torque 6. Since all printing units 1 - 6 run at the same speed, the torque distribution also corresponds to the power distribution. It can be seen that at the critical nodes of FIG. 4, the first force input point 21 and the second force input point 36, there are always clear directions of force flow. The gear train leading to the right of the force input point 36 to the printing unit 4 is always flowed through in the direction of the arrow pointing to the left, even at the speed ratios <1.

In the arrangement of a second embodiment shown in FIG. 6, the power is fed from the first supply line 8 into the gear train 22 via a first force input point 37 located in front of the first printing unit and from the second supply line 9 via a second force input point 38 between the third and fourth Printing unit lies. This expediently results in a split of moments between hydraulic and mechanical torque, which is illustrated in the following diagram in FIG. 7. In this case, at the maximum speed of the machine, the output of the printing units 5 and 6 is completely covered, and the output for the printing unit 4 is half covered by the second supply line 9. It also applies here that there are clear directions of force flow at all speed ratios below 1.

It is clear from the torque requirement diagrams of FIGS. 4 and 7 that the addition of the second supply line 9 relieves the pressure on the transmission lines leading the power transmission between the printing units. If one of them assumes that the central drive, ie the drive between the printing units 4 and 3, is necessary for a clear determination of the direction of the force flow in order to avoid flank changes, the advantage of the proposed measure becomes particularly clear.

The progression of curve "b" or "d" can be changed in a simple manner by changing either the degree of filling of the hydrodynamic clutch 12 (more or less oil content) or the slip between the clutch primary part 11 and the clutch secondary part 30. A change in the constant slippage, which in the normal design is brought about by correspondingly rigid transmission ratios between the coupling primary and secondary parts 11 and 30, can be brought about by additionally switching a continuously variable transmission 39 into one of the two supply lines 8 or 9. With the aid of a continuously variable transmission 39 arranged in the second supply line 9 as shown in FIG. 8, it is possible to reverse the power flow in the second supply line 9 in such a way that the clutch secondary part 30 rotates faster than the clutch primary part 11.

In this case, power flows back via the second supply line 9, so that reactive power flows via the first supply line 8, the first force input point 21, the connecting line 40 and the second supply line 9. In this way, the meshing in the gear parts concerned in the described circle can be additionally loaded if necessary. The latter application shows how advantageously the engagement of a hydrodynamic clutch 12 in a second supply line 9 can be used to achieve several effects, in particular when a continuously variable transmission 12, which only has to have a small adjustment range, is used as an additional variation member.

PARTS LIST

• 1 - 6 printing units
• 7 drive motor
• 8 first supply line
• 9 second supply line
• 10 drive shaft
• 11 coupling primary part
• 12 hydrodynamic clutch
• 13
• 14 belt drive
• 15 V-belt pulley
• 16 wave
• 17 spur gear tooth pair
• 18th
• 19 stub axles
• 20 drive wheel
• 21 first force input point
• 22 gear train
• 23
• 24-29 spur gear
• 30 coupling secondary part
• 31 belt drive
• 32 V-belt pulley
• 33 wave
• 34 spur gear tooth pair
• 35 journal
• 36 second force input point
• 37 first force input point
• 38 second force input point
• 39 continuously variable transmission
• 40 connecting strand

Claims (4)

1.Drive with power split for multi-color rotary printing presses with a row arrangement of the printing units, which are connected to one another via a gear train and are driven via two force input points, each of which is supplied with power from a common motor via a supply line,
characterized,
that the supply line (9) which feeds the second force input point (36, 38) leads to a cubically increasing power with the speed. 2. Drive according to claim 1,
characterized,
that a hydrodynamic coupling (12) is switched on in the supply line (9) feeding the second force input point (36, 38). 3. Drive according to claim 1 and 2,
characterized,
that the coupling primary part (11) and the coupling secondary Part (30) of the hydrodynamic coupling (12) are in drive connection with one another in such a way that there is a constant speed ratio between the two, the primary coupling part (11) rotating faster than the secondary coupling part (30) facing the second force input point (36, 38). 4. Drive according to claim 1 to 3,
characterized,
that between the hydrodynamic coupling (12) and the second force input point (36, 38) a continuously variable transmission (39) is switched on in the second supply line (9).

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