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Members press release

Schunk, Germany - IFR-Partner

Standardized RCC axes for high-speed assembly

June 2013

Lighter, more rigid, more dynamic: when complete Z or Y axes are to be moved in high-precision high-speed applications, the linear modules of SCHUNK's LCx series set a new benchmark. The profiles of the world's first standardized linear motor axes made of rein-forced carbon composite weigh around 58% less than the profiles of comparable aluminum modules. They can be accelerated and moved in an extremely fast and energy-efficient fashion. The reinforced carbon composite brings about a whole bundle of other advantages: for example, because of the high elasticity modulus of RCC, the axes also have superior bending and torsional stiffness. Their excellent internal damping reduces vibrations and ensures outstanding dynamic stiffness. Since the thermal expansion of the material is minimal, the axes ensure high precision even when they heat up during operation.

Excellent dynamics and repeat accuracy

Light-weight modules in the LCx series use proven high-speed LDx high-speed modules from SCHUNK. They owe their high dynamics and repeat accuracy to a servo-electric linear motor drive. Without mechanical transmission elements, the driving force is transmitted by high-precision drive elements, free from play, directly to the slide. Precision-cut steel guide rails additionally increase accuracy. Standard equipped with absolute-value transducers, the modules provide excellent repeat accuracy of 0.01 mm per axis. They soon pay for themselves especially in highly dynamic joining and placing processes due to their extremely short cycle times, maximum precision, and consistently high process stability. Since the modules have almost no parts that wear, both the maintenance costs and the number of unplanned down-times drop to almost zero. The absolute-value transducer eliminates the need for expensive homing when the system boots and after emergency stops. In addition, the axes need neither end nor reference sensors, reducing the investment costs, programming costs, and number of cables in the cable set.

Compact system design

The modules are impressive in terms of space as well: powerful servo motors achieve such high rated forces that smaller sizes usually suffice or, in vertical applications, greater masses can be moved. Since the motor, measuring system, and linear guidance are integrated directly into the axis profile or slide, the modules are extremely compact and require very little space. In addition, multiple freely programmable slides on a profile guide enable especially compact and low-priced concepts. For use as a Z-axis, a parking brake may optionally be added to the modules.

The standardized carbon axes come in two versions: one is the LCN version with a simple X profile, in which the axis reaches a rated force of 200 N and a maximum driving force of 500 N. The other is the LCM module, which is designed for moderate loads, is equipped with a wide double X profile, and achieves a rated force of 400 N and a maximum driving force of 1,000 N. In both versions, the maximum acceleration is 40 ms−2, the maximum speed is 4 ms−1, and the maximum useful stroke is 1,200 mm. The modules can be used both horizontally and vertically, optionally with a static profile, and moving slide or with a static motor and moving profile. The axes are controlled with Bosch Rexroth IndraDrive controllers as standard; a Siemens SINAMICS S120 drive is also possible as an option. Because SCHUNK offers all LDx modules with the standard interfaces Profibus, Sercos III, Profinet IO, EtherNet/IP and EtherCat, the modules can be quickly and easily integrated into higher-level system controllers.