Implementing local drive networks with integrated master/slave function in DC drives


Electronics integrated in DC motors creates extensive advantages for decentralised drive technology in woodworking machines. A master drive controls and monitors a number of slave drives in a local network and therefore considerably relieves the higher-level PLC. The result – shorter cycle times, higher productivity, lower installation costs for the machine and less programming effort for the higher-level PLC.


In the woodworking industry the financial pressure on companies is always in the centre of attention, particularly here in this country. That's why they demand maximum productivity, minimum cycle times and low investment costs through affordable machines. Machine manufacturers can only respond to these demands with sophisticated automation. They are supported in this by the automation equipment manufacturers, like Bonndorf-based Dunkermotoren. The specialist for drive technology based on brushless DC servo motors has now introduced a broad spectrum of DC drives with integrated electronics in its extensive modular system. These compact drives totally fulfil all the user's wishes and requirements.

Electronics supports decentralised drive technology
To achieve high flexibility and short setup duration, woodworking machines are more and more equipped with decentralised drives. Individual motors adjusts formats, carriages and sensors to each required position. With their high reliability and robust yet affordable construction, brushless DC servo motors are ideal for this application. They gain special advantages through their integrated electronics and the spectrum of special functionalities achieved as a result. So these drives can cope with simple to extensive automation tasks. From electronic commutation, through speed control and positioning, up to a local, independently-controlled network, the integrated electronics can now take over diverse sub-sections of the drive automation, without having to access the processing power and memory capacity of higher-level drive amplifiers and controllers.
Especially in woodworking machines, a number of drives repeatedly have to be moved to programmable positions. These include, for example, the transverse adjustment for sawing laths and boards. The same applies to the format adjustment on profile milling machines. In the past, the format adjustment was manually operated via adjusting wheels. Today's state-of-the-art systems are mostly decentralised drive concepts which receive the necessary positioning data from the higher-level PLC, via a bus system. In this case, the "recipe", or in other words, the description of the profile, including the travel data for the individual positioning drives needed for this profile, must be programmed and stored on the higher-level PLC.