Zero backlash couplings

When fitting stepper motors, servomotors, gearboxes and encoders to machines, care must be taken to ensure all devices are co-axial (no angular or parallel misalignment). Failure to do so will place excessive loads on bearings and reduce the life of the components. Using flexible couplings with some angular and parallel compliance will ensure this while maintaining constant velocity and low backlash. The Bervina flexible couplings are constructed from a one-piece aluminium, steel or stainless steel section. There no wearing parts to require lubrication and they are constant velocity.

The couplings are manufactured by cutting several helical slots into a solid cylindrical section. Because they are machined from a single section, they are constant velocity couplings and do not cause backlash in position control systems.

Two types are available. The six-beam couplings consist of two sets of three helical slots providing good parallel offset. The three-beam couplings consist of one set of three helical slots and are shorter so they can be installed in confined spaces. Both clamp fixing and set screw fixing versions are available, the clamp version having greater gripping torque.