What are the common applications of linear guides?

A linear guide is a linear assembly with a double parallel track containing a load support ball or roller.As the backbone of many industrial applications,they provide low-friction guidance and high stiffness for loads ranging from a few grams to thousands of kilograms.Its various sizes,accuracy grades,and preloads make linear guides suitable for almost any performance requirement.

Single rail applications

Because linear guides have load support balls(or rollers)on each side of the guide,they can withstand cantilever loads even if only a single guide is used.(In contrast,round-axis linear guides must be used in pairs when cantilever loads are present.)Because of this feature,many applications use a single linear guide rail to save space or prevent misalignment problems between other components in the system.Here are a few examples of applications using a single linear rail.

Linear actuators - Linear guides are usually the preferred guide mechanism for actuators driven by belts,screws,or cylinders because of their ability to withstand torque loads.They can also accommodate driving speeds of up to 5 m/sec,which is important in belt or pneumatic drive systems.

Linear actuators typically consist of a single linear guide rail with one or two bearing housings.

Gantry Robot - The defining feature of Gantry is that it has two X (and sometimes two Y and two Z) axes.Each shaft usually contains a single linear guide rail and is driven by a screw or belt and pulley system.With two axes working in parallel (e.g. X and X'),very good torque capability can be achieved even with only one linear guide rail per axis.

When the two axes work in parallel,the bending moment capacity is very high even with only one linear guide rail per axis.This example shows two X-axes (each with a linear guide),one Y-axis,and one Z-axis.

Dual rail applications

When high moment loads are present, linear guides can be used in pairs,which can decompose the moment loads into forces on the bearing housing.In this configuration,the actuation mechanism can be installed between linear guides,making the whole system very compact.Dual linear guide applications include:

Linear Stages-- Stages are typically very high precision systems,which means high stroke accuracy and minimum deflection are critical.Dual linear guides are often used to ensure maximum stiffness and bearing life,even when the load is concentrated on the stage with little or no torque load.

Linear guides are usually used for stages requiring a longer travel length than air bearings or cross-roller sliders.

Machine tools - Like Stages,machine tools require very high stroke accuracy and stiffness to ensure that the tool produces high quality parts.The use of two guides in parallel(usually with two bearing houses per guide)ensures that the deflection is minimized.The machine tool will also bear very high loads,so solving the load on the four bearing houses helps to maximize the bearing life.

load capacity and stiffness requirements of machine tools usually require the use of bilinear guideways-ball or roller type

Cartesian robots - Since Cartesian robots typically use only one linear system per axis,it is important that each axis can withstand high torque loads.This is why most Cartesian robot axes are constructed from linear actuators that contain two linear guides in parallel.

A Cartesian robot consists of a single axis using a bilinear guide,such as a double-rail actuator driven by a ball screw shown here.

Robotic Transport Unit - Six-axis robots provide flexible movement for applications requiring extension and rotation in multiple directions. However,if the robot needs to move to another workstation or work area,the dual-track system can act as a "seventh axis" to transport the entire robot to the new location.A significant advantage of linear rail in these applications is the ability to connect multiple rails with very long travel lengths,often in excess of 15 m.

The robotic transport device uses two parallel linear tracks and is capable of carrying up to 2,930 kg of weight with a maximum travel of 30 meters.

https://www.autolinearmotion.com/linear-guideways.html