Linear guides, also known as linear rails, are used to support and guide the rolling elements, typically rollers or balls, of a linear bearing. Linear guides provide a smooth surface for the linear bearings to travel in addition to allowing for controlled, precision movement rather than free, unrestrained motion.
Utilized in a broad spectrum of applications, linear guides serve industries including: industrial manufacturing, for use in CNC machining centers and material handling applications such as industrial robots; medical and laboratory, for used in devices requiring high levels of cleanliness; semiconductor, where they are used in assembly and for precision part applications; and food and beverage, for processing and packaging applications. Additional industries that utilize linear guides include aerospace, automotive, optical, textile, commercial, marine and agriculture for use in applications such as engine compartments and office machinery as well as diverse automated processes. In order to be used in corrosive or sanitary environments, linear guides are constructed from a wide range of materials including aluminum, stainless steel, steel, bronze and even some plastics, although they are much less commonly used than metals. Additionally, lubrication may be added for enhanced mobility as well as increase service life.
There are many different types of linear guides. The most basic breakdown is whether the linear guide is manual or motorized. Manual linear guides are very simple in design and consist of a solid, flat metal body and one or two metal bars that are grooved in order to guide the linear bearings. Motorized linear guides are similar in construction to manual linear guides, but which a few additions. Much more complicated in design, some common types of motorized linear guides include belt guides, rack guides, screw guides and chain guides. Linear belt drives have the addition of a belt that can be made from various elastomers, that allows for quiet, yet high speed linear motion. Linear rack guides are used for applications in which the role of the carriage and the guide are reversed; meaning that the guide moves and the carriage remains stationary. This type of linear guide is best-suited for applications requiring maximum use of available space as well as when long work tracks are required. Linear screw guides typically utilize either spherical worm screws or trapezoidal screws and require very low torque motors since the screw is most often coupled directly to the motor. This type of linear guide is used in applications with tight tolerances as they are capable of extreme precision. Lastly, linear chain guides are often used as alternatives to belt guides in high temperature environments and are mainly employed in lifting applications.
