Renishaw Next-Generation FORTiS Enclosed Linear Encoders Offer Enhanced Metrology And Reliability For Machine Tools

Delegates at EMO Milano 2021 are invited to the Renishaw stand to learn about the new enclosed encoder that enables machine tool builders to improve machine tool performance and increase uptime while enhancing the efficiency of assembly, maintenance and servicing.

The innovative FORTiS enclosed linear absolute encoder series is designed for use in harsh environments such as machine tools. It can also be used in functional safety applications up to SiL2 and PLd.

The FORTiS encoder design is built upon industry-proven RESOLUTE encoder technology and provides high resistance to the ingress of liquids and solid debris contaminants. It features an extruded enclosure with longitudinally-attached interlocking lip seals and sealed end caps. The readhead body is joined to a sealed optical unit by a blade, which travels through the DuraSeal lip seals along the length of the encoder. Linear axis movement causes the readhead and optics to traverse the encoder's absolute scale (which is fixed to the inside of the enclosure), without mechanical contact.

Ian Eldred, Principal Mechanical Engineer at Renishaw, highlights a range of unique and ground-breaking design features, coupled with the recent introduction of Functionally Safe (FS) variants:

“The new FORTiS enclosed absolute encoder range is the culmination of years of R&D effort at Renishaw. It delivers superior repeatability, reduced hysteresis and improved measurement performance due to an innovative non-contact mechanical design that doesn't require a mechanical guidance carriage. Five years of accelerated life testing, under the harshest conditions, has enabled Renishaw to develop and refine the new advanced DuraSeal lip seals. These offer excellent resistance to wear and machine tool lubricants, superior sealing and ingress protection up to IP64 when combined with air purge.”

He continues, “FORTiS absolute encoders also feature integrated, specially-designed tuned mass dampers that deliver class-leading 30 g vibration resistance and push the limits of what enclosed encoders can endure. Installation of FORTiS encoders is quick and easy, which will help our customers save manufacturing and servicing time. Furthermore, with the growing industrial trend towards risk reduction for systems and processes, we were committed to providing Functional Safety variants for all FORTiS enclosed encoders. We are delighted to offer FS certified products to the market so soon after launching the FORTiS range.”

Customers can choose from two different extrusion profiles to suit their space requirements.

The FORTiS-S linear encoder is the standard-sized encoder, available with measuring lengths from 140 mm to 3040 mm and is installed directly to a machined surface via flexure holes in the extrusion's body.

The FORTiS-N encoder, available with measuring lengths from 70 mm to 2040 mm, features a narrower cross-section extrusion and a more compact readhead to enable installations in confined spaces. This model can be mounted directly to a machined surface via two end cap mounting holes or a mounting spar for greater rigidity.