COMPONENTS
TECHNICAL REFERENCE
Lubrication will also increase the maximum linear velocity that a DualVee bearing arrangement can endure. In ap- plications where high speed or high acceleration rates are present, lubrication of the wheel/track interface is highly recommended. Lastly, lubrication will reduce the overall coefficient of friction of the guide, which, depending on the level of preload, can fall anywhere from 0.008 to 0.015. The availability of lubricators and wheel covers gives design engineers an opportunity to design lubrication right into the DualVee mechanism with little effort. See specifications on wheel covers and lubricators for more details (pgs 16 and 17).
The other main factor affecting wear resistance is lubrica- tion. Wheel covers or lubricators should be designed in whenever possible. Both will distribute a thin coating of oil lubricant along the contact surface of the DualVee track. The wheel covers offer added protection by preventing debris from entering the wheel/track contact surface. Lubricated and relatively clean wheel/track contact surfaces will ensure maximum service life in a DualVee linear guide.
As the hardness of the contaminants approaches the hardness of the track and wheels, the wear rate will increase. For these cases, an adjustment factor (see page 23) should be applied to maximum axial and radial working load capacities to provide a longer operating life.
Lubrication Lubrication is the key to maximizing the life of a DualVee linear guide. Internally, DualVee guide wheels are lubri- cated for life with an extreme pressure, corrosion resis- tant grease.
The lubrication of the wheel/track interface is the respon- sibility of the user.
Lubrication of the guide ways will maximize the load capacity of the system and will significantly increase the service life over a non-lubricated configuration under the same loads. A light machine oil or an extreme pressure grease will minimize wear, stick slip, and corrosion on the guide ways in a DualVee-based design.
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Wheel Carriage Configurations In designing a wheel carriage, it is important to use the right combination of eccentric and concentric guide wheels depending on the configuration. The linear systems should always have two concentric wheels and all the other guide wheels should be eccentric. The ec- centric wheels are adjusted to remove the play between the wheels and track, equally loading all the wheels so they roll instead of sliding or skipping on the track due to acceleration. When the wheel carriage is loaded in the radial direction, the concentric wheel should carry the primary load.
Eccentric Wheel
Wheel Carriage
Load
Concentric Wheel
Concentric Wheel
Wheel Carriage
Load
Eccentric Wheel
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