Zero-backlash splined couplings for robotic applications
Ruland, a brand distributed in Italy by the Genoese company Getecno, offers zero backlash splined couplings designed for use in robotics applications. In particular, the RL and RS series allow for different combinations of outer diameter and length; moreover, they are able to compensate for any misalignment at low bearing loads.
Ruland offers slit couplings for robotic systems. Slit couplings are zero-backlash, lightweight, and manufactured with intermittent slit cuts, making them an ideal starting point for designers of robotic systems. While they are visually similar to Ruland multiple beam couplings, the slit cut design gives them higher torque and torsional stiffness capabilities and multiple length options in the same outer diameter, allowing coupling performance to be tailored to system requirements.
Slit couplings have torque comparable to that of a single disc coupling, torsional stiffness similar to a stainless-steel beam coupling, and misalignment consistent with an aluminium beam coupling. This combination of features allows a slit coupling to be used in-place of one of these styles which all have limitations such as no accommodation of parallel misalignment in a single disc coupling. The proprietary slit pattern with radiused (as opposed to squared) edges reduces stresses that build up during misalignment and under torque loads, increasing effective service life and allowing for better performance when compared to other slit couplings available in the market. Along with low mass and inertia, these characteristics make slit couplings a good choice for robotic systems.
High torsional rigidity to enable high torque and speed
Robotic applications such as those found in medical, surgical, factory and warehouse environments often require a zero-backlash coupling with high torque, torsional rigidity and speed. These robots can start, stop and reverse constantly, necessitating the use of a responsive coupling. Along with other performance benefits, slit couplings have a moderate amount of dampening, which is useful in robots that require vibration control, such as material handling and articulating robots. Slit couplings are offered in RL and RS series for a range of outer diameter and length combinations. RL series couplings have longer lengths, allowing for greater parallel misalignment capabilities, increased torsional stiffness and greater distances between shafts. RS series couplings are designed to fit in compact spaces and offer parallel misalignment capabilities, an upgrade to the single disc coupling, which has comparable torque but no accommodation for parallel misalignment. Both series accommodate all forms of misalignment with low bearing loads and have a balanced design allowing for speeds up to 70,000 rpm.
Slit couplings are available in clamp screw and set screw designs with bore sizes ranging from 1.5 to 12 mm.