The Hephaist Seiko range of spherical rolling joints, which are available through Heason Technology, are excellent for axial alignment of parallel kinematics and high-precision positioning mechanism such as Hexapods and Stewart Platforms. Providing backlash-free axial rigidity but allowing radial and angular freedom of movement, the SRJ units offer a very compact alternative to combining traditional roller bearings to achieve joints with three degrees of freedom - with significantly increased rigidity.
The design includes an SUJ2 steel mounting base with a precision ground sun sphere connected via a very low friction ball cage retainer to a planetary sphere; this has a threaded shaft for mounting to the customer's parallel joint or actuator mechanism. Maximum swing angle is +/-30 degrees and, in the radial plane, complete freedom of movement is permitted. On request, alternative materials can include stainless steel, and the SRJ can also be supplied with vacuum-compatible grease.
Base diameters from 19-mm are available in eight sizes with threaded connecting shafts from M3 to M28. Axial load ratings are up to 10,600N in the push (compression) direction and 16,000N in the pull (tension) direction.
For more information, visit www.heason.com/catalogue/224/bearings.html.