Off-The-Shelf Solution for Noncircular Grinding

Noncircular grinding is used in a wide variety of automated manufacturing applications, such as the production of camshafts, crankshafts, cams and eccentric shafts. It’s an extremely complex task because the contour leads to constantly changing engagement and movement conditions between the grinding wheel and the workpiece.

NUM Corp. (Naperville, IL) addresses this difficulty by adding noncircular grinding functionality to its NUMgrind cylindrical grinding software, an application-specific element of the company’s Flexium+ CNC platform. Fully compatible with other Flexium software from release 4.1.20.00, the enhancement  enables manufacturers of CNC cylindrical grinding machines to easily and inexpensively add noncircular grinding capabilities.

NUMgrind simplifies the creation of G-code programs for CNC grinding machines through the use of a highly intuitive graphical human machine interface (HMI), conversational-style dialogues, or a combination of the two.

Unlike conventional CAD/CAM workstation tools for generating CNC machine tool control programs, NUMgrind is intended for the production environment. Shop floor employees can quickly handle everyday machining tasks and easily share work among several people and several machines. The NUMgrind HMI can also be run on an office PC. Application-dependent projects and the corresponding ISO part programs can be created, tested with Flexium 3D simulation software, and transferred to the targeted machine.

The operator determines the sequence of the grinding process via the HMI and enters the necessary data for the grinding operations, grinding wheels, and dressing operations in the dialogue pages. Programming is simplified by an HMI that’s supported by a comprehensive library of predefined shapes, which includes eccentric circles, hexagons, pentagons, polygons, Reuleaux triangles, and rhombi. The CNC program is then automatically created and stored in an executable form.

The closed shape of the workpiece is defined in the XY plane. However, grinding is performed by interpolating or synchronizing the X-axis with the C-axis (workpiece spindle). Axial movement in the Z-axis can also be accommodated via oscillation or multiplunge. The Flexium+ CNC system’s NCK transforms the contour from the XY plane into an XC plane and calculates the corresponding compensation and in-feed movements, taking grinding wheel diameter into account. Speed and acceleration automatically adapt to the machine’s capabilities.

www.num.com