Schunk Launches Composite Linear Modules

23 August 2013

The linear modules of SCHUNK's new LCx series set a new bench-mark for the high-precision and high-speed movement of Z or Y axes. The lighter, more rigid and more dynamic linear motor axes are the world's first standardized motor axes made of reinforced carbon composite (RCC).

With a weight approximately 58% lighter than 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, the high elasticity modulus of RCC gives the axes superior bending and torsional stiffness. Their excellent internal damping reduces vibration 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 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 directly to the slide. Precision-cut steel guide rails further increase accuracy. As standard the LCx series is equipped with absolute-value transducers to provide excellent repeat accuracy of 0.01mm per axis. The modules soon pay for themselves 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. In addition, the axes do not require end or reference sensors, reducing the investment costs, programming costs and number of cables in the cable set.

Compact system design

The modules are also impressive in terms of space. The 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.

The standardized carbon axes come in two versions. One version is the LCN version with a simple X profile whereby the axis reaches a rated force of 200N and a maximum driving force of 500N. The other is the LCM module, which is designed for moderate loads and is equipped with a wide double X profile. This achieves a rated force of 400N and a maximum driving force of 1,000N. In both versions, the maximum acceleration is 40ms−2, the maximum speed is 4ms−1, and the maximum useful stroke is 1,200mm. 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. Be-cause SCHUNK offers all LDx modules with the standard interfaces Profibus, Sercos III, Profinet IO, EtherNet/IP and EtherCat, the mod-ules can be quickly and easily integrated into higher-level system controllers.