CNC machine suppliers underscore accuracy, safety

The latest releases adopt ball screws and linear slide guiding rails, and have emergency shut-off switches.

TOP TRENDS

• Stepper motors lead: Most suppliers employ such mechanisms because they are less costly and widely available. The presence of 50 to 100 magnetic poles also makes stepper motors easier to control. Topping 2,000rpm, however, these are not suitable for high-speed production. Servo types, meanwhile, are capable of 80 to 90 percent accuracy at rapid rates but require a position encoder. These are often sourced from Japan and used in upscale machines.
• Increased precision: For drive screws, companies are adopting ball types as the components are suited for fast-paced operation and withstand heavy load. Makers are also incorporating linear slide guiding rails from Japan's THK and Taiwan’s AMT, which have high speed, accuracy and movement sensitivity, and low resistance.
• Safety features: Most CNC machines are equipped with an emergency shut-off switch in case of a malfunction. Some units may have more than one. Several also feature pressure mats that halt operation automatically when a person comes too close to the machine. Dust- and sound-resistant enclosures to block flying debris are common as well.
• http://www.globalsources.com/gsol/I/CNC-machine/a/9000000129383.htm