Friday, January 05, 2007

Grinding wheels and nozzles changed automatically

Developed to achieve the most cost-effective grinding, the latest Schutte WU 305 five-axis universal tool and production grinding machine is equipped with an automatic wheel changer.

Developed to achieve the most cost-effective grinding of cuttingtools and components, the latest Schutte WU 305 five-axisuniversal tool and production grinding machine is equipped withan automatic wheel changing system and magazine able to hold fourdifferent wheel and arbor assemblies. As part of the wheel changeprocedure, coolant nozzles are also automatically exchanged inorder to ensure delivery is optimised for each size and shape ofgrinding wheel. Available from Traub Heckert UK, the grindingperformance of the WU 305 is maximised through the use of directdrive digital AC motors to grinding spindle, universal rotaryaxis and C-axis positioning.

The compact, high-performancegrinding spindle has a 15 kW power rating giving up to 12,000revs/min while the three linear axes have maximum feed rates of24 m/min.

The closed-loop universal workhead rotary axis ispowered by a 4.7 kW motor capable of 2,500 revs/min and iscapable of high accuracy positioning within 0.0002deg via theC-axis.

It will accommodate components up to 250 mm diameter by570 mm between centres.

The WU 305 is capable of cylindricalgrinding, helical grinding and grinding features such as the fullradius on ballnose cutters, step drills and shell end mills aswell as special tool forms.

In addition, production cylindricalgrinding and heavy duty plunge grinding can be carried out due tothe inherent rigidity of the machine.

On machine inspection canbe carried out via an integral 3D Renishaw probe mounted on thegrinding head.

The probe, for instance, is able to determineunclamped length, diameter, helix lead and indexing position ofthe spiral flute on the circumference of cutting tools such asend mills and feeds the data direct to the Siemens control fromwhich the automatic grinding cycle is initiated.

The machine iscompact having a footprint of just 1718 mm x 1840 mm with axistravels of 400 mm by 250 mm by 250 mm.

The machine is designedwith the grinding wheelhead set at 30deg to the vertical with thecentre of the wheel close to the centre of the workheadrotational C-axis to maximise rigidity.

And, because thelongitudinal guideway is inclined at 30deg, coolant effectivelywashes away grinding debris into the coolant tank filter systemand makes the rotary axis more convenient for manual loading.

Anoptional automatic workpiece loader that is integral in themachine is available for parts between 4 mm and 32 mm diameterand weighing up to 1.2 kg.

The pallet system is mounted on thelongitudinal axis of the machine with the workpieces positionedvertically.

The table and head axes are used to position thepick-up for transferring the workpiece from the pallet to theworkhead.

During grinding, the loading arm is parked in a safetyzone over the wheelhead of the machine.

The WU 305 uses theSinumerik 840D control system with Windows-based 'openarchitecture' special Schutte grinding software that is easyto use allowing programs to be entered or edited on the machinewith full graphics support.

There is a wide choice of menu-driventool-specific programs with operator prompts to simplify andspeed up programming for milling cutters, drills, step drills andstep tools as well as profile knives and cutting tools used inwoodworking and plastics machining.