In horizontal movements, friction is one of the most important factors when determining the energy needed to drive an axis. For applications in environments with low contamination levels, low friction seals can significantly reduce the drive power requirement. Compared with standard seals, they reduce the friction between the runner block and the profiled rail by up to 50 percent. This may be a small detail in an individual application, but seen globally, it adds up to a big effect. About ten million ball runner blocks are manufactured around the world every year. If just half of these were equipped with low friction seals, users could save up to 230GWh of electricity per year with the Size 25 runner blocks alone. That corresponds to the annual electricity demand of a city with a population of 200,000.
Besides friction, the weight of the components themselves is another major factor in the drive power equation, especially in vertical axes. The light weighting components and modules of the eLINE series from Rexroth are setting new standards here. Their hybrid design combines a wrought aluminium alloy for the body with hardened antifriction bearing steel for the running tracks and balls, which reduces the overall weight of profiled rail systems by about 60 percent. The innovative eLINE Compact Modules or the Feed Modules VKK from Rexroth are ideal for use in handling applications as vertical axes or actuators. With their low moving system mass they reduce the required drive power, while providing extremely precise and stepless positioning.
In 2009, Rexroth will be expanding its portfolio of miniaturised linear motion products. With their more compact design and lower weight these products offer higher performance for less energy input