A different ball game

When Lealde had a problem with sourcing a linear encoder suited to the requirements of its newly developed lathe it needed an innovative approach to encoder technology.

When Lealde, one of six industrial companies that make up Spanish machine tool giants Danobat Group, had a problem with sourcing a linear encoder suited to the requirements of its newly developed lathe, a solution was found by employing the services of Leicester-based Newall Measurement Systems and its innovative and successful approach to encoder technology.

Manufactured in Spain, the TCN-24 is the largest in the range of universal horizontal lathes manufactured by Lealde.

It has a triangular saddle and trapezoidal bed for the heavy duty turning of large components up to 900mm in diameter.

The slant bed allows for rapid chip and coolant evacuation.

Lealde's aim was to get a development model up and running at EMO Milano 2003 for prospective customers to see in action.

It sounds simple enough, but as Newall's technical director Dr Mark Hudman explains, it wasn't all plain sailing: "With a bed length of 3 metres, the TCN-24 machine for EMO was right on the length limit of conventional encoders that employ glass scale technology, and though such variants are available, they are often expensive.

Also, the TCN-24 is designed for heavy duty machining applications such as axle manufacture, which means there is often a lot of contamination present in the form of flood coolant and large quantities of swarf.

These applications, with plenty of vibration, shock and contamination, do not lend themselves to the deployment of optical equipment such as glass scale encoders".

"Lealde wanted a more robust solution that could match the accuracy of glass scale encoders at a more cost effective price.

At first they thought this would be difficult to source, that is until they contacted us".

Newall encoders use steel ball based inductive technology.

As they employ no moving parts and there is no reliance on optical technology, they not only provide a solution to the problems of vibration, contamination (Newall encoders are IP67 rated), length and cost, they also offer other advantages such as a high resistance to thermal drift, something important in many metal cutting environments where temperature is unregulated.

Digital versions also have the connectivity and processing power that allows direct communication via a laptop computer, permitting programming, interrogation and diagnostics to take place at machine-side.

Another benefit is that inductive technology encoders are extremely fast in comparison to other types of encoder technology.

Newall set to work, initially providing an engineering survey (both mechanical and electrical) on the TCN-24.

This was followed by a trial installation on the EMO-bound machine with full training and commissioning provided for the Lealde engineers to ensure full product familiarity.

Newall fitted a 3m long Spherosyn (stainless steel housing) encoder to the bed length (z-axis) of the TCN-24 and a Microsyn (carbon fibre housing) encoder to the x-axis, both feeding into an existing Fanuc controller.

Leadle was very pleased with the project and the TCN-24 made its debut at EMO Milano as planned.

"For an OEM, a commitment of this scale is a large investment - to specify any new component on a range of machines is a significant step", says Dr Hudman.

"But I think this project has opened a few eyes at Lealde and we are hopeful that it will progress into production.

It is certainly a lot less expensive than alternative options and there is little doubt that this high accuracy solution overcomes their previous concerns regarding vibration and contamination".

Back to top