Vollmer introduces grinding machine for small diameter tools

Tool sharpening specialist Vollmer has launched the VGrind 340S grinding machine. Complementing the existing VGrind series of machines, the latest VGrind 340S has been specially developed for producing and re-sharpening small carbide tools with diameters from 0.3 to 12.7 mm.

Drills and milling cutters in this size range are in high demand in the automotive, electronics, connector and medical engineering sectors, where assembly space and components are becoming smaller and smaller. The automation options on the VGrind 340S allow tool manufacturers to use the machine for unmanned production around the clock.

Vollmer’s VGrind 340S, which was first presented at the EMO 2019 exhibition in Hanover, is not just suitable for producing rotationally symmetric tools, but for re-sharpening. The machine relies on the company’s tried-and-tested VGrind technology to achieve this functionality.

VGrind see two vertical spindles made available for different grinding wheel sets, which makes it possible to reduce non-production time. Five harmonised CNC axes achieve interpolation, with short travel distances for the linear and rotary axes. These machine kinematics reduce idle times and the subsequent time required to machine workpieces.

In addition to the rotary axes, the linear axes are also designed as direct drives (linear drives) for the first time. Unlike ball screws, these axes are non-contact drives and are therefore not subject to wear, increasing the service life, precision and longevity of the machine. The VGrind 340S also features a steady rest to ensure optimum tool concentricity during grinding, while a back rest is available as an option for longer drilling tools.

NUMROTOplus software enables a 3D simulation of the tool production process and makes it possible to carry out collision monitoring in advance. The height-adjustable and pivoting touchscreen control desk, as well as the generously dimensioned view of the machining space, make for ergonomic machine operation.

Solutions for automation, such as the HP 160 pallet magazine or HPR 250 free-arm robot, ensure that precision machining of up to 900 tools with different shank diameters can continue unattended. The VGrind 340S features a replaceable dressing device for the grinding wheels to achieve optimum concentricity and axial run-out for the wheel packages. An optional probe enables in-machine grinding wheel calibration and offers the option of recalibrating the handling mechanism as often as required. In addition, the wheel coolant nozzles can be replaced automatically, just like the wheel packages themselves.

"Machining small tool diameters requires a great deal of finesse, which we have been able to achieve through digital and mechanical solutions,” says Dr Stefan Brand, CEO of the Vollmer Group. “Actuation via five CNC axes and the use of back rests guarantee precise machining in the micrometre range."