Exlar’s component planetary roller screw line has been
expanded to include two performance capacities, available in PRS and PRR
models. The PRS models, with G5 lead accuracy, are available in screw diameters
ranging from 8- to 80-mm, and deliver static load ratings up to 218,000-lbf.
Exlar’s PRR models, with G9 lead accuracy, are available in screw diameters of
12- to 27-mm and offer static loads up to 18,000-lbf.
Exlar’s roller screws are a superior mechanism for
converting rotary torque into linear motion. They function in a similar manner
as acme screws or ball screws, with a nut traveling on a threaded shaft. However,
unlike acme or ball screws, Exlar roller screws are capable of carrying heavy
loads—at high speeds—with high duty cycles for thousands of hours in the most
arduous conditions. This makes them an optimal choice for demanding,
continuous-duty applications. Exlar roller screws are also an ideal replacement
for ball screws, due to their longer travel life in the same compact size.
In applications where high loads are anticipated, or faster
cycling is desired, Exlar roller screw actuators provide a superior alternative
to hydraulic or pneumatic solutions. Electromechanical systems using roller
screws offer major advantages, as they do not require a complex support system
of valves, pumps, filters and sensors. Thus, roller screw based systems require
much less space and deliver significantly long working lives with minimal
maintenance. Further, these systems eliminate hydraulic fluid leaks and
significantly reduce noise levels, resulting in highly efficient operation.
Electromechanical systems also offer increased flexibility, making them
suitable for diverse applications.
Loads and Stiffness: Due to design factors, the number of
contact points in a ball screw is limited by the ball size. Alternatively,
Exlar’s planetary roller screw designs have significantly more contact points
on comparably sized ball screws. Increased contact points enable roller screws
to provide higher load carrying capacities, plus improved stiffness. This
results in minimal space requirements to sufficiently meet the specified load
rating.