As the core equipment for complex tool manufacturing, CNC tool grinding machines can accurately process cutting tools such as milling cutters, drill bits, and taps with multiple curved surfaces and cutting edges. The core logic is to transform the tool design model into a solid product through a closed-loop system of "digital trajectory planning multi axis coordinated motion grinding wheel precision cutting real-time accuracy feedback", achieving controllable shaping of complex shapes. This process is not supported by a single technology, but the result of the collaborative action of multiple systems.
Digital trajectory planning is the prerequisite for complex tool forming. The cutting edge curve, spiral groove, and back angle of complex cutting tools need to be accurately defined through 3D modeling. The CNC system uses specialized programming software to analyze the model data and generate the motion trajectory of the grinding wheel. Unlike ordinary grinders, its trajectory planning needs to take into account both "tool geometry characteristics" and "grinding process requirements". For example, when machining a spiral end mill, the system needs to plan the spiral feed trajectory of the grinding wheel based on the spiral angle parameter, while reserving grinding allowance to ensure subsequent precision machining accuracy. In addition, the software's built-in tool process database can provide adaptive trajectory optimization solutions to avoid interference between the grinding wheel and the tool blank.
Multi axis collaborative motion is the core execution mechanism of molding. CNC tool grinders are usually equipped with 3-6 linked coordinate axes, which are driven by servo motors to achieve multidimensional motion between the grinding wheel and the workpiece. During processing, the workpiece rotates around its own axis, and the grinding wheel completes actions such as feed, cut in, and retreat according to the planned trajectory. Multi axis linkage ensures that the grinding wheel always acts on the tool processing surface at a constant angle and speed. For example, when machining the spherical cutting edge of a ball end milling cutter, the X-axis and Z-axis drive the grinding wheel to perform circular motion, while the C-axis drives the workpiece to rotate synchronously, so that the grinding trajectory conforms to the spherical curve, ensuring the smoothness and roundness accuracy of the cutting edge.
The adaptation of grinding wheels and the matching of cutting parameters are key guarantees for the quality of forming. The materials (such as high-speed steel and hard alloy) and processing characteristics of complex cutting tools are different, and corresponding types of grinding wheels need to be selected. For example, diamond grinding wheels are commonly used when processing hard alloy cutting tools to ensure cutting efficiency and durability. At the same time, the system dynamically adjusts the grinding parameters based on the characteristics of the tool, such as reducing the feed rate to reduce vibration when machining the back angle of the tool, increasing the grinding wheel speed to improve surface quality when machining spiral grooves, and balancing machining efficiency and accuracy through parameter optimization.
The real-time accuracy feedback and compensation mechanism is a closed-loop guarantee for forming accuracy. The equipment is equipped with grating rulers, laser measuring heads, and other detection components to collect real-time position data of the grinding wheel and workpiece. If machining deviation is detected (such as excessive edge runout), the system will automatically adjust the coordinate axis motion parameters or grinding wheel position for error compensation. For example, when processing multi edge milling cutters, the laser probe detects the height difference of the cutting edge edge one by one, and the system eliminates the deviation by fine-tuning the Z-axis position to ensure consistency in the accuracy of each cutting edge.
In summary, CNC tool grinders have broken through the precision and efficiency bottlenecks of complex tool forming through the synergistic effects of digitization, multi axis collaboration, precision cutting, and closed-loop compensation, providing core technical support for tool manufacturing.