Demmeler Automatisierung & Roboter GmbH Takes advantage of the MSR, the new concept of accionamiento of Redex Andantex

Alta dynamic and high power. These are, in summary, the central requirements of the manufacturers and users of machines-tool regarding the rotary presses tables CNC. Demmeler Automatisierung & Roboter GmbH, with headquarters in Heimertingen/Allgäu, is a prestigious manufacturer of these components that contribute a degree of additional freedom to the mechanised of metal by start of shaving.

Demmeler Offers tables giratorias that they can arrive to have diameters of until twelve metres and capacities portantes of until 500 tonnes. Between his customers stand out the manufacturers of big machining centres that allow, for example, the mechanised of carcasas of aerogeneradores or big gears. Of course, the program of production of Demmeler includes also rotary presses tables CNC smaller.

The circular tables CNC of Demmeler are famous all over the world by his high precision.

In addition to the guided, that in the case of the tables giratorias heavier is of hydrostatic type, the precision of the accionamiento has a very decisive importance, even when it treats to move loads of a lot of tonnes. Only then it can guarantee that the processes of mechanised realizar with the precision wished. To all this it is necessary to add that during the milling or high turning strengths repercuten on the piece of work that, in last term, have to be absorbed by the table giratoria and his accionamiento. Therefore, the effort to the that is subjected the accionamiento is very high.

Historically, the accionamientos of the rotary presses tables consisted in a combination formed by an accionamiento main for the mechanised by turning and a servo-reductor, usually without game, for the twist in function of axis C.

An accionamiento main provides to the dish the pair of accionamiento total during the continuous way (turning). This accionamiento is generally composed by a box of straight gears of parallel trains, that includes a box of transmission of 2 speeds to expand the rank of speed to constant power of the engine in accordance with the diameters mín/máx of the piece to mechanise. It provides high pair to low speed for operations of desbaste of steel or smelting and high speeds in operations of semiacabado or finishing.

By his part, the accionamiento auxiliary in way axis C provides 100% of the pair of accionamiento to low speed for operations of milling and positioned. In this way, the accionamiento main has to happen ready neutral (deadlock) and be dragged. When it requires happen to continuous way (turning) again, the pinions of the accionamiento auxiliary have to desconectarse of the accionamiento.

Looks for : a system of accionamiento simpler keeping the highest levels of precision. Demmeler Has come adapting this concept of accionamiento to his tables. Nevertheless, given his complexity and his high cost, the engineers looked for an able alternative to offer at least the same precision or even something upper, but whose construction and utilisation resulted simpler.

Redex Andantex, mudialmente recognised manufacturer of accionamientos of precision for machines-tool, developed does some years the range MSR, until reaching the necessary maturity for his production in series entirely in his installations (image 2). This solution combines the two functions of accionamiento described previously in one, by what fulfils with the criterion of the simplification required by Demmeler. The basic construction of the system consists in two trains of identical gears (pinions twins) where each one composes of an engine of cabezal, a box of change of 2 speeds type MSD with a reenvió angular integrated on which mounts the pinion that meshes directly with the toothed crown of the dish. These 2 accionamientos combined deliver the load during the mechanised by turning with a relation 50:50. This wants to say that both turn in the same sense.

In the operations of milling and positioned the CNC conventional (Fanuc, Siemens, etc) manage a system of precarga master-slave on the same accionamientos to cancel the game in all the system, an engine acciona and the another brakes. In this case it would work in way ‘axis C', without the need to resort to additional mechanical components.

This extremely compact system provides a solution key in hand since because of his high degree of integration can be mounted directly in the table and, optionally, is possible to suppresses the reenvío angular, according to the construction of the machine in question. As it offers the system of accionamiento for pairs of twist until 9.000/18.000 Nm (in this case are two the motors of 100 kW that provide the pair of necessary twist), is possible to move pieces of work very big with maximum precision and mechanise the same with some very narrow tolerances. In case of a relation between pinion and toothed crown of, for example, between 2 and 5, is possible to achieve pairs of twist in the upper table to 400.000 Nm and reaches a global transmission (gear more pinion/tops toothed) of 217/57. The CNC guarantees the coordination of all the operations of movement and mechanised.

The advantages of the new system of accionamiento of Redex Andantex already have remained of self-evident in the practice. Demmeler Uses the new system with the designation ‘Duo Drive' in his last generation of tables giratorias CNC and only can give testimony of positive appearances. Bernhard Eberhard, responsible of design of Demmeler Automatisierung & Roboter GmbH: “The new solution is clearly simpler and economic, what does that our tables giratorias are even more competitive”. The designers do not have to take into account any additional system for the function of axis C and the synchronisation of the two accionamientos. Like this the coordination of the operations of movement with the tool of milling, realizar practically ‘in direct' by means of the control CNC, that is to say, without need of any type of mechanical components and/or electronic additional.