The traditional approach to accommodating parallelism tolerances in linear motion systems is to use two linear slides or track systems operating in parallel, with one free to float so that the two guidance systems do not 'fight' each other. However, designers are often hampered by a limited choice of components and sometimes even the need to specify special parts.
Now, thanks to the development by HepcoMotion of a new Floating Bearing with vee-profile, such linear motion systems can be implemented based on the HepcoMotion GV3 and PRT precision ring track ranges. HepcoMotion Vee slides, ring and tracks are available in an exceptionally wide range of formats and sizes, and with standard carriage plates, lubricators and other complementary parts.
For the majority of parallel systems, therefore, HepcoMotion says that an off-the-shelf product is now available, and one that is not subject to 'special' prices and long lead times. Technical Director Peter Fanshawe states: "We expect our floating bearings to be particularly popular in conjunction with ring and track applications. It is in these situations where flat track and roller solutions are not available as standard and are not so easy to engineer."
Choice of sizes and variants
In providing axial movement (float) to compensate for parallelism between the opposing vees, the HepcoMotion Floating Bearings reduce the potential of additional loading and help to maintain a consistent running quality. They are available in three basic sizes to work in harmony with the GV3 and PRT ranges. Furthermore, they may be specified with one of two stud lengths to cover most thicknesses of carriage or mounting plate; the short stud version is compatible with HepcoMotion carriage plates.
Both versions of the stud are available in three different types. The concentric type is fixed, providing a datum for the system, and the eccentric and double eccentric types provide for adjustment, with the latter having sufficient movement to permit disengagement of a ring encircled by bearings. To allow for high speeds and lifetime lubrication, all versions feature caged needle roller bearings. And to protect them against the ingress of debris, they have nitrile seals.
Fanshawe concludes: "Our new Floating Bearings provide the perfect technical answer for specific applications within the framework of our standard range. They enhance the breadth and depth of our product programme and demonstrate our continued commitment to offering an optimum solution to even the most complicated motion problems."