Motion Without Limits® Application Notes


As a matter of good engineering practice the DualVee components should not be used where their wear or failure could cause personal injury


Track Mounting In most DualVee applications, accuracy plays a small role in the successful implementation of a guide wheel system. The flatness, straightness, and parallelism of the plate or bar to which the DualVee track is attached (bolted) de- termine the accuracy of the system. Cold finished or extruded bar or plate is adequate for many applications. The DualVee track incorporates a mounting shoulder to locate the track on the bar or plate.


TRACK FLAT BAR OR PLATE


STRAIGHT &


PARALLEL


Greater accuracy is obtained by using a plate or bar that has been ground flat and parallel on the mounting surfaces. To achieve straightness and flatness character- istics to within N grade accuracy levels is fairly routine (± .004 inch; ± 0.10 mm). In fact, accuracies as low as ± .001 inch (± 0.03 mm) have been achieved using carefully prepared mounting surfaces in relatively short stroke appli- cations (1-3 feet; 0.3-1m). For designs requiring accuracy levels of ± .005 inch and better, mounting surfaces must be prepared straight and flat, and appropriate doweling or reference edge assembly techniques must be employed.


TRACK


For single carriage measured at any point along the rail: Variation in carriage height: ± .004 inch (± 0.10 mm) Variation in carriage width: ± .004 inch (± 0.10 mm)


For multiple carriages measured at the same location along the rail: Variation in carriage height: ± .001 inch (± 0.025 mm) Variation in carriage width: ± .001 inch (± 0.025 mm)


Figure 2 Allowable tolerances for straightness and flatness of travel — grade N


Track Life - Hardened/Unhardened Track For maximum loading and heavy continuous use, the “T” series hard edge track should be used. For prototype or light duty intermittent use, the “TS” series unhardened track can be used at a lower cost.


Long Track Lengths - Track Splicing Considerations Precut lengths of track are not suitable for butting end to end. Please contact the factory when track lengths longer than the maximum avail- able single piece lengths are required. Track that is suitable for butting is available on request. When constructing track systems longer than 20 feet, the joints on parallel tracks should be staggered for greater accuracy and smoothness.


Staggered Joint


Staggered Joint


Harsh (Dirty) Enviroments/Wear Resistance Since the circumference of the wheel is greater at the major diameter than at the minor diameter, there is a constant wiping action on the track producing a self cleaning effect. As such, DualVee guide wheels are employed in a wide variety of harsh environ- ments, including the presence of metal chips, powders, fibers, slurries, etc. It is important to note that such envi- ronments will often limit the service life of a DualVee linear guide to some extent.


Figure 1 Running parallelism end view 25 © Bishop-Wisecarver Corporation 2011. All rights reserved. www.bwc.com 888.580.8272


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32