1 year ago

MDA Technologies 5/2014

MDA Technologies 5/2014


Drive Technologies 03 The LPBK + right-angle gearheads make sure the trays are accurately positioned 02 Generation 3 LPB + low-backlash planetary gearheads help position the sealed cups exactly on screw conveyors 04 Wolfgang Beckmann (centre), Karl Schmitt (left) and Peter Hempsch (right) gripping the cups, gluing the sleeves or placing the containers in the trays – is quite awesome. The gearhead design unites an enveloping worm wheel with a cylindrical worm shaft. “This combination guarantees high transmittable torques. It‘s suitable for varying loads and speeds, and the large tooth contact surfaces mean mechanical wear is reduced to a minimum,” explains Karl Schmitt, Product Manager at Wittenstein alpha in Igersheim (Germany). The special tooth geometry of the V-Drive + gearheads assures the constant, lifelong accuracy that is vital in high-precision servo applications such as this. “In contrast to the majority of our competitors, we chose a geometry with hollow-flank teeth because when the torque is selected based on T2Servo values, the increase in torsional backlash that is normally accepted over time is virtually zero, resulting in constant, high positioning accuracy”, Schmitt adds. Another advantage of the V-Drive + gearheads‘ special tooth geometry is their higher efficiency due to the improved build-up of the required oil film in the lines of contact between the worm wheel and the worm shaft. At the same time, the optimized lubrication of the hollow-flank teeth means there is no stick-slip effect. Schmitt sheds light on the technical issues involved: “This tendency to slip back is extremely undesirable and leads to uncontrolled motions; it can often be observed with other tooth geometries if an oil film has not yet built up between the gearing parts, in other words at high gear ratios and low speeds”. Powerful solutions In addition to the servo worm gearheads in the V-Drive + series that have proved effective both at the main drive and in the robot modules, sema also uses high-precision right-angle and planetary gearheads for a number of functions. The innovative magazine solution for carton blanks is just one example. “It allows the machine operator to place new stacks into the magazine without a climbing aid”, Wolfgang Beckmann remarks. The mechanism that receives and positions the blanks is driven by means of a timing belt. Right-angle gearheads in the HG + hypoid series ensure maximum precision and repeatability when the blanks are removed from the stack. In another application realized by the Yeo Valley machine, Generation 3 LPB + low-backlash planetary gearheads help position the sealed cups exactly on screw conveyors – and control the grippers precisely when the trays are stacked in the robot modules. Innovative, technically reliable and economical – these are the hallmarks of the Wittenstein alpha gearheads installed in sema Systemtechnik‘s packaging machines. The lifelong precision of these worm, bevel and planetary gearheads is fundamental to the high availability of the secondary and tertiary packaging lines. It comes as no surprise that machine manufacturers like sema and end customers like Yeo Valley trust in gearhead solutions built by Wittenstein alpha. About Company name: Wittenstein alpha Headquarters: Igersheim, Germany Turnover: 254 million Euro Employees: 1,900 worldwide Products: Low-backlash planetary gearheads, Servo-right-angle gearheads, Linear systems, Mechatronic system solutions, Stage and lifting technology, sensors 20 MDA Technologies 5/2014

Product News New roller bearings for large gears NSK presents two new series of large gears for industrial gears, which differ from the previously available series with a clearly increased service life. The bearings use a special material that leads to considerably improved resistance against different types of breakouts (“flaking”) in combination with a special heat treatment. Thus, the manufacturer offers a counter-measure for a damage pattern that occurs, among others, in the large roller bearings used, e.g., in wind turbines. The resistance of the new roller bearings against “White Structure Flaking” has been increased by a factor of seven. While the service life increases by a factor of two under common conditions, it can be increased up to three-fold if the lubricants are strongly contaminated. Universal speed control with Danfoss VTL Automation Drive Many countries worldwide have established statutory efficiency classes for electric motors. More and more innovative technologies for three-phase motors, including induction, permanent-magnet and synchronous reluctance motors, claim to achieve the highest energy efficiency. The VLT Automation Drive by Danfoss is the first VLT platform that is able to operate all of these motor types efficiently using adapted algorithms. For users, it is therefore advantageous to be able to operate all motor types with just one type of frequency converter, because this distinctly reduces the previously described extra effort and expense. In principle, nearly all motors can be operated with programmed curves that specify the required voltage for every speed or frequency (voltage versus frequency characteristics). However, the theoretical efficiency of each motor technology can only be achieved in practice with control algorithms specifically adapted to the individual technologies, as otherwise it is not possible to optimize operation for every operating point with variable load. The frequency converter makes commissioning easy with additional functions such as automatic motor adaptation, which measures the motor characteristics and optimizes the motor parameters accordingly. This way the motor always operates at the highest possible efficiency, allowing users to reduce energy consumption and cut costs. Linear technology by Rodriguez: suitable for harsh applications The linear technology offered by Rodriguez ranges from simple roundrail via profile rails to cross roller guides, including entire linear systems, which combine the guide and drive in a single unit. In this way, the company offers a suitable solution for almost all motions required. For example, a ball-screw drive with a toothed belt drive and sliding guide is used in an orbital saw. The linear unit feeds the saw to the semi-finished product (tubes with a length up to 8,000 mm) with a feed precision of ± 0.3 mm. The semi-finished offcuts are then returned via the linear guide. Due to the large output length of the semi-finished products, a long stroke had to be created. For this specific linear unit, it reaches 12,000 mm. The resulting long travel lengths allow large saw lengths without changing grip. The belt drive of these units consists of a plastic toothed belt with steel cord inserts. It runs between two belt pulleys, one at each end of the profile. A belt pulley is connected to the motor and the other is mounted onto a tensioning station. The belt can be re-tensioned, whereas the load remains on the carriage. The prism sliding guides used are self-aligning. According to the manufacturer, all linear units manufactured by Rodriguez stand out thanks to their low noise emission, low overall weight, compact structural dimensions and durability. Sealing via a magnetic stainless steel cover strip with a self-clamping feature also allows applications under harsh operating and ambient conditions. For demanding applications, the company also supplies corrosion-resistant and chemicalresistant finishes. MDA Technologies 5/2014 21


WORLD OF INDUSTRIES - Industrial Automation 1/2017
WORLD OF INDUSTRIES - Industrial Automation 2/2017
WORLD OF INDUSTRIES - Industrial Automation 3/2017
WORLD OF INDUSTRIES - Industrial Automation 4/2017
WORLD OF INDUSTRIES - Industrial Automation 5/2017