The DirectDrive Pioneers
MAN Roland has pioneered the direct drive concept over decades
These days direct drive is state of the art with web offset presses and it is not only here that MAN Roland has done pioneering work over decades. At the same time that this concept was introduced for series production of web presses more than ten years ago, the development engineers in Offenbach were already working on direct drive for sheetfed offset presses.
Within a few years a new drive principle for web offset presses gained acceptance: instead of one main drive, many decentrally arranged and electronically controlled motors provide precise output. The developments in sheetfed offset appear to be similar; the idea being that direct drive enables a printer to produce as many short run jobs as possible each day. Therefore, for maximum makeready time reduction, MAN Roland offers the DirectDrive system for simultaneous plate changing as well as simultaneous washing functions. At least for the present, other press manufacturers are only offering simultaneous plate changing. Whether at a high or low technological level – it appears that the time for direct drive for sheetfed offset presses has arrived.Web offset: developments started in the 1970s
MAN Roland’s know-how in individual motor drives goes way back to 1973 when Augsburg development engineers, together with partners from the supply industry, succeeded in driving two gravure printing units each with its own synchronized DC motor. 1988 saw the introduction of shaftless dual-motor drive on a commercial web press, the ROTOMAN. The printing units and folders had separate drives. From 1991 until 1994 theoretical and practical tests led to the introduction of an eight-page commercial web press with individual motor drive. Every printing unit, the chilling unit, and the folder superstructure had its own motor.
Sheetfed offset: patents granted in the 1990s
At drupa 1995 MAN Roland introduced individual motor drive for newspaper presses. The GEOMAN eight-couple tower shown there was at that time the world’s first and only web press to use individual motor drive and printed newspapers in excellent quality. In the following years all major web press manufacturers adopted the individual motor drive technique that is now state of the art.
At the beginning of the 1990s, the sheetfed press design engineers in Offenbach started developing the theoretical basis for a DirectDrive concept. Can the web press drive principle be applied to sheetfed presses? What benefits would this bring?As a result a patent was applied for in 1996 that led to the granting of the German patent DE 196 23 224 C1, the European patent EP 0 812 683 B1 and the US patent US 05826505 A. The patent specification precisely describes the advantages of decoupled, directly-driven plate cylinders, albeit in a somewhat sober manner: “Due to the individually driven plate cylinders that are independent of the remaining cylinder system … tasks such as plate changing or cylinder washing can be attended to more flexibly. With the blanket cylinders disengaged … it is thus possible … with the aid of appropriate devices to change plates in all printing units semi- or fully-automatically … etc.”
Thus the idea was born and implementation then followed. The DirectDrive development project started in 2003 under the direction of Dr. Holger Wiese, who is cited in the patent specification as co-inventor of the direct drive principle for sheetfed offset presses.In the new millennium: ready for series production
More results followed already in 2004 and several more patents were applied for. For example, the plate cylinder double clutching system was granted the German patent DE 10 2005 036 786 B3. The first ROLAND 700 DirectDrive test press was running in the factory. The printing unit with direct drive presented at drupa was a show-stopper and innovation highlight. Intensive development work resulted in production-viable presses and the first field tests in 2005. Here the thorough preparation based on know-how gathered over decades paid off. The level of dependability was much higher than expected. Mathieu Siemons from Drukkerij Vrijdag b. v. in Eindhoven, Holland, one of the first field test sites, reports that during the entire field test year the press was available 87 percent of the time. “It all went much better than promised. There were never any great difficulties that would have prevented production of a job.” Thomas Götz from Druckhaus Götz in Ludwigsburg, Germany, also confirms this: “Since it started up, the test press was practically always available; the counter already showed 18 million sheets after just ten months.” All the field test users reported makeready time savings of up to 35 percent thanks to the simultaneous functions.
More than just simultaneous plate changing
The field tests were successfully concluded more than six months ago and dozens of serially produced ROLAND 700 DirectDrive printing units are running all over the world. Competitors are following suit; there are indications of a development similar to that for web presses – the drive principle of the future is gaining ever greater acceptance. This is because many sheetfed printers with frequent job changeovers and short runs are looking for time-saving possibilities through for example:
• Simultaneous and fully-automated plate changing in all printing units
• Simultaneous wash-ups at different speeds for inking units and blanket and impression cylinders
• Simultaneous plate changing and wash-ups which equates to ZeroTimePlateChange
• Electronic start-of-print adjustment for repeat perfecting jobs with different sheet sizes
This provides users with competitive advantages. They benefit especially from the many years of experience that pioneer MAN Roland has, with DirectDrive not only offering simultaneous plate changing but also many more simultaneous makeready functions. The industry recognises this as well – in 2007 the ROLAND 700 DirectDrive received the German Printing Industry Innovation Award, and the InterTech™ Technology Award from PIA/GATF in the United States.
