Linear Guideways Keep Loads on Track

If a motion control application needs a way to precisely guide, support and carry a load in a straight line, chances are a linear guideway may be required, as these high-quality devices are designed to provide smooth, low-friction movement in applications that require highly precise, linear movement.

Linear guideways generally comprise a stationary linear rail and a mobile carriage responsible for motion. This setup enables smooth movement with minimal friction, ensuring exceptional strength and precision down to the micrometer level. By incorporating ball bearings, these guides facilitate rolling motion between the rail and carriage, enabling seamless movement with reduced friction. Consequently, these systems demand less energy for operation, enhancing overall efficiency. These motion control components are pivotal in preserving accurate motion along a single axis, especially in precision-critical applications like CNC machines, grinding, milling, boring equipment, and medical devices.

The Advantages of Using Linear Guideways

High-quality linear guides, such as PMI linear guideways from Accu Tech USA, provide many advantages over conventional slide guides in applications that require straight-line, smooth motion with low friction, high speeds and accuracy. Users can expect to find:

  • High positioning accuracy and high repeatability: Because linear guideways utilize rolling motion with a low-friction coefficient. This means that “stick/slip” will not occur during submicron feeding, so users can count on high levels of positioning accuracy over and over again.
  • Low-frictional resistance: The frictional resistance of a linear guideway is minimal when it is presented in a slide guide. Additionally, with a properly designed linear guideway, lubrication can be easily supplied through the grease nipple on the carriage or by using a centralized oil pumping system, further decreasing frictional resistance and maintaining accuracy for long periods.
  • High rigidity and high strength: With an optimal four-way load design, linear guideways are capable of bearing loads in all four directions: radial, reversed radial, and two lateral directions. Furthermore, carriages can be equipped with preloading or joined together to enhance system rigidity.
  • Suitability for high-speed operation: Due to the low-frictional resistance, the required driving force is low, so high speeds can be accommodated without a lot of power consumption. Additionally, linear guideways are not prone to temperature increases, even during high-speed operation.
  • Simplified installation: Linear guides offer high precision, even if the mounting surface is machined by milling or grinding, making them simpler to install than conventional slide guides and they are often easily interchangeable for maintenance purposes.

Types of Linear Guideways

Because they are critical in many motion control applications, there are a variety of linear guideway types available. Some of the most reliable linear guideway types include full-ball, full-roller, ball-chain and roller-chain styles. Below we explore each type, as well as the applications for which they are best suited:

Full-ball linear guideThis type of linear guideway offers smooth movement, self-alignment, and low noise. Full-ball type linear guides are also easily interchangeable. Full-ball linear guides are available in heavy-load and compact versions for applications such as machine centers; CNC lathes; heavy-cutting machine tools; grinding, milling and boring machines and machine tools; measuring equipment; welding machines; and automated packing machinery. They also come in a compact style that is suitable for use in electronics; office equipment; wafer transfer equipment; printed circuit board assembly tables; medical equipment; and inspection tools. A wide-rail type is available for applications such as binding machines; laser cutting equipment; and automated packing equipment.
Full-roller/heavy-load typeFull-roller, heavy-load linear guideways offer the ability to manage ultra-heavy loads with ultra-high rigidity, smooth movement and low noise, as well as a good lubrication effect. They are well suited to applications such as machine centers; lathes; grinding machines; five-axis milling machines; jig borers; drilling machines; horizontal milling machines; mold processing equipment; and EDM machines.
Ball-chain/heavy-load typeThis type of linear guideway provides self-alignment capabilities, as well as a ball-chain design for heavy loads, high rigidity and smooth motion. They are also easy to lubricate and interchangeable. Ball-chain, heavy-load linear guides excel in applications such as lathes; heavy-cutting machine tools; grinding, milling and boring machines and machine tools; EDM equipment; measuring equipment; welding and binding machinery; and automated packing equipment.
Roller-chain/heavy-load typeRoller-chain, heavy-load linear guides provide high rigidity in ultra-heavy load conditions. The roller-chain design offers smooth motion and low noise. They find use in lathes; grinding and milling machines; jig borers; horizontal milling machines; mold processing equipment; and EDM equipment.
Linear guide with ballscrew unitFor compact applications that require high rigidity and accuracy, an actuator manufactured with a linear guide and a ball screw unit combines the carriage of the linear guideway and the nut of the ballscrew to provide a complete, but compact carriage nut. The carriage nut serves to operate efficiently with the U rail to provide high rigidity and high accuracy in a limited space.

With so many types to choose from, linear guides are the go-to device when support, guidance and smooth, straight-line motion with very little friction are critical specifications. They are often used in applications where high accuracy and reliability are essential, so the component must be robust and accurate, as well as in applications where the total weight of an object must be fully supported as it moves in a straight line. For more information about how Accu Tech’s PMI linear guideways can provide straight-line motion with the reliability and accuracy needed for your application, please contact an expert at Accu Tech USA, a JHFOSTER company.