For dynamic applications like semiconductor fabrication and pick and place machines — where fast acceleration and deceleration are critical requirements — chances are your main criteria for positioning tables are speed, fast response and compact size. As you explore the wide variety of linear positioning tables available, look closely at the drive system. In order to find the ideal characteristics you need for your dynamic application, you will have to weigh the options of choosing driving mechanisms based on ball screws, lead screws, belts or linear motors.
While each drive type has its advantages, linear motor-driven positioning tables provide the high speeds, fast response and accuracy these applications demand. For example, NT Nano Linear Series positioning tables integrate direct drive linear motor technology to deliver high thrust force and respond to fast changes in motion with accuracy and high repeatability. Here’s how:
The Linear NT’s structure consists of a high-performance neodymium magnet and optical linear encoder scale — built into the steel table — which are deployed as a slide table, and an air-core coil and linear encoder head, which is deployed as a stator within the steel bed. Neodymium boasts exceptional magnetic properties and high magnetic strength.
In keeping with Fleming’s left-hand rule, the coil is subject to horizontal force. This is due to flux that always works in the vertical direction from the magnet and coil yoke, and rotational flux that is generated by the coil current. When the direction of the coil current is switched to match the direction of the flux, continuous thrust is created in that same direction, maintaining the slide table’s linear motion. Electric current control regulates the acceleration and speed profile of the motion, and feedback from the linear encoder contributes to the excellent positioning accuracy.
To optimize positioning accuracy, an IKO linear or crossed roller way can be combined with the linear motor and high-resolution encoder. The result: very high speed and acceleration with very good resolution and repeatability.
Our NT Series of linear tables comes in a variety of versions to accommodate various dynamic applications, including:
- NT…V (standard) for ultra-compact applications. The smallest unit in the family is only 38 millimeters wide with a 62-millimeter overall length and just an 11-millimeter sectional height.
- NT…H for high-accuracy applications. Offering maximum thrust of 25 Newtons, this positioning table features exceptional attitude accuracy of 5 seconds or less and straightness of 1 micrometer or less. NT…H tables are desirable for semiconductor and liquid crystal-related equipment.
- NT…XZ for pick and place applications. Measuring just 18 millimeters wide, this ultra-thin unit allows users to change strokes according to application requirements.
When your dynamic application needs to achieve fast and responsive linear positioning during acceleration and deceleration, it pays to choose positioning tables with linear motor drive technology. IKO NT Series linear motor-driven positioning tables deliver large thrust forces for fast acceleration and deceleration, good response and accuracy — all in a compact unit. Be sure to contact our sales engineers to help select the best positioning table for your high-speed equipment.
For more information about IKO International’s Nano Linear NT Series direct drive motor positioning tables, visit our product page.