Renishaw Mini Readhead Fits into the Tightest Spots
Designed for use where conventional enclosed readheads won't fit.
OEMs can custom-fit linear encoders to the tightest spots with a mini readhead that Renishaw Inc (Schaumburg, IL) is calling its smallest ever. The new miniaturized linear encoder readhead is said to bring rugged, reliable, non-contact operation and high-speed, high-resolution capabilities to size-sensitive applications, even in shopfloor conditions.
The RGH34 packs its capabilities into a thumbnail unit small enough to fit on the face of a 25 cent piece with room to spare. The new RGH34 readhead measures just 0.63x0.63x0.35 in. (15x15x8.8 mm), yet delivers state-of-the-art performance, operating at speeds up to 48 ft (15 m)/second with resolutions as high as 0.2µ.
Typical applications include size-sensitive, high-precision linear motion applications such as microstages, microscopes, and ultra-small linear actuators.
The RGH34 features open, non-contact optical systems that eliminate friction, hysteresis, and wear. The mini readhead runs on 40µm pitch scales with 1.5mm ride height and wide setup tolerances. Patented filtering optics average reflections from multiple scale facets, ensuring excellent signal stability and accuracy even with contamination or minor damage to the scale. Industry standard analog voltage and RS422 digital outputs are available.
Supplied in component form, the FGH34 allows custom-engineering by OEMs to maximize design flexibility and packaging efficiencies, but requires attention to EMC/RFI issues. Installation is simplified with a patented LED setup indicator that indicates when optimum installation conditions are met, thus optimizing manufacturing productivity. The tri-color LED (green, orange, and red) gives continuous indication of signal strength and overcomes the need for a specialized setup, test and service kit. Tri-state error indication on the incremental output channels warns of low signal amplitude during operation, eliminating the danger of encoder count loss.
The RGH34 uses an RGS42 "rolled gold" scale made from thin, flexible steel strip, gold-plated for high reflectivity and corrosion resistance. Offered in pre-cut lengths or continuous "cut and tape" rolls up to 229 ft (70 m), the scale features a self-adhesive backing for mounting to most engineering materials, including metals, ceramics, and composites. Direct-mounted to the machine, the scale matches the thermal expansion of the base materials, keeping differential movement between the scale and substrate close to zero, even over significant temperature ranges. Scale installation is quick and easy at any stage of machine build without need for drilling.
Renishaw Inc, 623 Cooper Ct, Schaumburg, IL 60173; phone: 847-843-3666