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ENCODERS
This Model TR1 TruTrac from Encoder Products Co. (EPC) is an integrated design with an encoder, measuring wheel and torsion arm. It provides linear-measurement feedback for New Tech Machinery’s mobile steel-roll form-and-cut machine.
cranes, wind turbines, food-and-beverage machinery and some medical devices. Usually, it’s either the failure of the encoder’s bearing (in the case of rotary setups) or contamination and signal loss that causes encoder failure. For example, ingress of dust from wood processing or steam from food-application cleaning cycles can quickly render encoders useless if they breach the housing. In applications where the design must track position along a linear axis, linear encoders are often the most suitable choice. These track location without intermediate mechanical components, even registering errors from rotary-to-linear linkages, so help controls correct for machine errors. One industry that makes copious use of linear encoders is the machine-tool industry ... especially for the manufacture of aerospace parts that necessitates precision milling and finishing.
Encoders at work in metal cutting
New Tech Machinery (NTM) makes a portable SSQ Multipro roof-panel machine for metal roofing contractors, installers and fabricators. Users can take the machine to jobsites and quickly cut metal roofing panels to any length. It works like this: A metal coil feeds into
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one end of the machine and gets one of 15 different profiles. Then the machine automatically cuts the metal to length. A rotary encoder tells the controller how much material has fed through, which activates the shear mechanism at the right time. NTM needed an incremental encoder to provide accurate linear measurement and withstand the rigors of outdoor operation. The encoder had to be small and (to get feedback directly from the metal surface) sport a measuring wheel. After testing and evaluation, NTM picked a Model TR1 TruTrac from Encoder Products Co. (EPC) and bought it from a local distributor. The compact TR1 encoder has an integrated measuring wheel and spring-loaded torsion arm. It operates in any orientation; it’s fully configurable with up to 10,000 CPR resolution; and it accommodates line speed to 3,000 ft per min. On the SSQ, constant spring tension keeps the measuring wheel in contact with the metal, and the pivot arm accommodates any panel movement. To date there have been no TR1 failures on any SSQs; NTM recently released a simplified (less costly) roofing machine and it also uses a Model TR1 TruTrac.
designworldonline.com
11/8/15 2:27 PM