Linear axes use carbon composites for higher performance

With a weight approximately 58 per cent lighter than comparable aluminium modules, they can achieve high speeds and high accelerations. The reinforced carbon composite results in many further advantages. For example, the high elastic modulus of RCC gives the axes superior bending and torsional stiffness. Their excellent internal damping also 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.

Dynamics and accuracy

Lightweight 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. Schunk says that 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 wear parts, both the maintenance costs and the number of unplanned stoppages drop to almost zero. In addition, the axes do not require end or reference sensors, thereby reducing the investment costs, programming costs and cabling.

The modules are also impressive in terms of how little space they require. The powerful servo motors achieve such high rated forces that smaller sizes usually suffice or, in vertical applications, greater loads can be moved. Since the motor, measuring system and linear guidance elements are integrated directly into the axis profile or slide, the modules are extremely compact and require very little space.

Schunk offers the carbon axes in two versions. One is the LCN version with a simple X profile with a rated force of 200N and a maximum driving force of 500N. The other is the LCM module that 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 1000N. In both versions, the maximum acceleration is 40m/s2, the maximum speed is 4m/s, and the maximum useful stroke is 1200mm. 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, or a Siemens Sinamics S120 drive is offered 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.

Contact Schunk for more information about the LCx series linear modules.