根据The Economistmagazine，制造业的第三次革命将由3D打印，新材料和协作制造服务带入。在过去的十年甚至过去五年中，任何观看3D印刷行业发展的人都可能同意。Gartner forecaststhat worldwide shipments of 3D printers will reach over 217,000 units in 2015 and will more than double each year between 2015 and 2018.
对于线性运动组件和系统的制造商和分销商来说，这是个好消息，因为尽管该过程可能会有所不同 - 从立体光刻到激光烧结到热塑性挤出，但实际上每个3D打印机的骨干都是线性运动系统。（有关3D打印技术的底漆，请参阅3D Printing Industry’s Beginner’s Guide。）和3D打印行业根据用户的多样性和打印机的预期目的为广泛的运动技术提供了机会。
Desktop 3D Printers
Desktop 3D printers can be loosely defined as those with a print area less than 10 in. x 10 in. x 10 in. These models range from kits costing a few hundred dollars to pre-assembled printers costing a few thousand dollars, making them within reach of home users, hobbyists, and small manufacturers. Nearly all desktop 3D printers use Freeform Fabrication (FFF, also called Fused Filament Fabrication) technology, which involves heating, extruding and depositing layers of thermoplastic material to build a 3D model.
由于动态要求相对较低，并且易于组装是主要考虑因素，因此这些打印机通常使用圆形轴和Belt-Pulley系统来移动挤压头。尽管这些组件提供了符合打印机规格的最低成本线性运动系统和定位，但它们很难安装和对齐，这可能会导致绑定和扭矩尖峰。随着时间的流逝，圆形轴和皮带系统也将发展反弹，这可能导致降解的印刷质量。通过自我对准和易于组装功能的线性指南有助于缓解这些问题，并通过降低维护并提供一致的构建质量来减轻打印机的性能和客户满意度。
P并3D打印机
Falling between desktop and professional versions, prosumer 3D printers can have a print area up to 18 in. x 18 in. x 18 in., and may be based on either FFF or Selective Laser Sintering (SLS) technology, which uses a laser to melt and fuse powered metal, ceramic, or plastic. With the ability to print larger models and a wider variety of print materials, prosumer 3D printers can be found in commercial and industrial applications, including part modeling and rapid prototyping.
In the prosumer range of 3D printers, requirements for larger print areas and smaller layer thicknesses lead manufacturers to use components such as linear rails and leadscrews, or even preassembled systems. As Mark Heubner, Market Development Manager at PBC Linear, explains, “Linear rails can provide pre-engineered alignment, which significantly reduces manufacturing and assembly time and service costs versus round shafts. And anti-backlash leadscrews provide better positioning and less positional degradation than belt driven systems. Leadscrews are also self-lubricating, which reduces maintenance and eliminates issues with oil or grease in the printer’s work area. All of these features contribute to lower manufacturing costs for the OEM and lower cost of ownership for the user.”
Professional 3D Printers
对于高精度零件，功能原型，工具甚至成品零件的型号，用户转向专业或工业级3D打印机。这些单元的打印区域最多可达1米（39英寸），层厚度（通常称为分辨率）为10微米。专业的3D打印机采用FFF，SLS，立体光刻（SLA），或者在某些情况下，具有印刷机制造商专有的技术。
To achieve smaller layers, better surface finish, and faster build times, manufacturers of professional 3D printers use higher precision and more robust linear motion systems, such as ball screws and profiled rail linear guides. At the highest end of the technology spectrum, linear motion is achieved not with mechanical drives, but with linear motors. As RJ Hardt, Applications Engineer at Aerotech explains, “The level of precision needed from the linear motion system is dependent on the feature size of the part being produced.”
Aerotech has significant experience with high-precision 3D printing applications, and one area that the company sees moving rapidly toward these smaller feature sizes is printed electronics, where he predicts that traditional mechanical drives, such as ball screws, won’t be able to keep up with the precision required by the application. Decreasing feature sizes and increasing precision also place higher demands on the motion control system, and this can become a sticking point for 3D printer manufacturers. According to Hardt, “Essentially, many manufacturers don’t allocate enough of their time and budget to this area. And no matter how precise the mechanical system, an inadequate control system will prevent the printer from producing the desired resolution.”
As material technologies advance and printing processes are refined, the use of 3D printing will increase among a wide range of products, from relatively basic consumer items to high-tech aerospace and medical components. But with so many technologies, end uses and manufacturers, it will be quite some time before the performance requirements of 3D printers exceed the capabilities of linear motion systems and controls – whether screws and profiled rail guides or linear motors and air bearings. The challenge for manufacturers of linear motion components and systems will be to educate designers and OEMs on the capabilities of each technology and help them as they lead the Third Industrial Revolution.
Filed Under:线性运动Tips,Ball screws • lead screws,Motors (linear)
