Direct-Drive Design Eliminates Backlash
The Direct-Drive Rotary System incorporates a rare earth permanent magnet torque motor with no mechanical gearing. This frameless motor wraps around the spindle, eliminating the need for a separate motor extension, which results in a smaller footprint. A ±0.077-arcsecond resolution, ±2.19-arcseconds accuracy encoder is mounted directly on the spindle to provide accurate positioning. According to the company, the direct-drive design eliminates backlash, which results in high servo stiffness, rapid and accurate bidirectional response and repeatability of ±2 arcseconds. The systems are said to require little maintenance and have fewer parts to wear than traditional gear-driven systems. A cross roller bearing in the front of the spindle and a tapered bore cylindrical bearing in the back of the spindle are designed to provide support and rigidity. The direct-drive models are also equipped with a drawbar actuator to accommodate multiple workholding devices. Various diameter face plates, collets and chucks can be interchanged. The DD100 4,500-degrees-per-second positioner is suited for drill and tap; laser processing; and intricate or high-speed milling applications. The larger DD200 and DD300 high-torque models include a slotted faceplate and a spindle brake clamp for off-center drilling and other high-force machining operations.
Editor PickRotary Tables Feature Dual-Lead Gearing System
Eastec 2017: Koma Precision will display Tsudakoma rotary tables in horizontal, vertical, tilting, multi-spindle and high-speed configurations.