Fully automatic, high precision CNC grinding machine for PCD/PcBN tool manufacture

The new RG9A enables high precision CNC grinding of both hard and ultra-hard materials

Launched in 2016, the RG9A is a fully automatic, high precision grinding machine designed to meet the sophisticated demands of toolmakers working with both hard and ultrahard materials, such as carbides, ceramics, PCD and PcBN.

Drawing on our 75 years of experience in designing machines for grinding and polishing diamond and related materials, the RG9A's construction ensures fast grinding times and repeatable accuracy to 2μm tolerances. The Coborn designed and manufactured wheel spindle is dynamically balanced to ensure minimal edge chipping of brittle and delicate tool materials. Programming is rapid, menu driven and straightforward for the operator and the ultra-fast vision system, with closed loop feedback, ensures minimum cycle times and maximum rates of throughput.

The RG9A is ideal for tool manufacturers making both small and large batch sizes. Individual tool set up times are quick and, if required, robot loading is available. From simple, single point shank tools to helical/radius multi-point rotary tools, the RG9A has all the characteristics, functions and capabilities needed to minimize tool production costs.

Tool formats possible

The RG9A meets the market demand for small, medium and large batch sizes in a very wide range of possible tool formats.

• Single point turning/milling inserts and shank type tools
• Simple radius and multiple blended radius tools
• Grooving tools with blended radii
• Large radius wiper inserts
• Multiple clearance angles
• Tools with K-land chamfers
• Rotary tools: end mills, reamers, single and multi-tooth cutters and saw blades
• Straight helical and radial helical cutters

Tool Formats

PCD/PcBN Square Grooving Tools

PCD/PcBN Radius Grooving Tools

PCD/PcBN ISO Inserts

PCD/PcBN Cassettes

Peripheral Ground Solid Inserts

PCD Step Drills

PDC Drilling Head Inserts

PCD Concave Ground Tools

CVD Dresser Roll

PCD Helical Rotary Tool

Multi-tipped Cutters

Orthopaedic Implants

Unique Automatic Features

With all the primary axes under software control (pivot, wheel in-feed, wheel traverse, planetary position, and if fitted rotary axis) the PG4 introduces many new and unique possibilities for automation and exacting finesse in the grinding process

The Vision System

Faster than contact probes, the ultra-high-speed vision system gives integrated, closed loop control of the machine using the image from the camera. The high resolution camera enables:

• Automatic alignment of the tool before grinding commences
• Automatic detection of the brazed PCD/PcBN blank position to eliminate crashes and minimise cycle times by reducing 'air–grinding'
• In–situ, intermediate and final inspection of angles, flanks and radii, measuring to an accuracy of +/- 2μm

CNC Programming

Programming the RG9A is simplicity itself. The software is:

• Menu driven and intuitive
• Designed with PCD/PcBN tool manufacture in mind
• Follows the steps associated with manual tool grinding

Each custom program is developed, either on or off the machine, by building the required sequence of 'blocks'. Operator training takes just 3 days for the basic five-axis machine and an additional 2 days for the rotary/helical programming course. The RG9A is a multi-tasking system and programs can be run whilst new programs are developed or old ones modified.

Rotary and Helical Tool Manufacture

The RG9A software enables complete control of the simultaneous movement of all axes. With coordinated movement of the rotary (RM) and linear (LM) axes, it is possible to grind the PCD edge of multi-tooth reamers where the PCD is laid on a helix angle. Since wheel-in feed position can also be controlled simultaneously, it is possible to create cutters which are both helical, and have a convex or concave radius.

Machine Axes

With the optional rotary module (RM) and the linear module (LM) axes fitted, the RG9A has 7 CNC machine axes and 3 CNC camera axes.

Optional Fixtures

Many optional fixtures are available and the most common are shown below. Coborn can also design and supply custom fixtures and tool holding solutions according to customer requirements

LM50 & LM100: Linear Axis

• Full CNC control
• Used with RM rotary axis for helical tool grinding
• 50mm or 100mm linear motion, respectively
• 0.1μm feedback resolution

RM130 (Pictured): Rotary Axis

• Full CNC control
• Indexing to 0.001° resolution or continuous rotation
• Face plate design for hydraulic chucking systems, HSK and ISO adapters
• Custom adapters available to special order

RM250: Rotary Axis

• As RM130
• Designed for grinding larger workpieces such a CVD rotary dressers and saw blades up to 150mm in diameter

TSU1: Manual Tailstock Units

• Provides a dead centre

TSU2 (Pictured): Hydraulic Tailstock Unit

• Provides hydraulic clamping for peripheral grinding of inserts between anvils
• Allows PcBN inserts to be OD ground and the K-land also applied

Optional Software Modules

• Cam (peripheral) grinding module
• Helical radial convex/concave grinding module
• CAD file import (dxf) module

RG9A Technical Specification