Numerical Controller Dynamic Positioning Completion Width
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In machine tools with rotary axes, the positioning completion check by angle is imprecise due to varying rotation radii, leading to uncertain determination of the instructed position, especially when the rotation radius is large, affecting machining precision on the workpiece.
Innovation Solution
A numerical controller that adjusts the positioning completion width of the rotary axis inversely proportional to the rotation radius, allowing for precise positioning completion checks at the tool center point by calculating a second positioning completion width based on the rotation radius, ensuring the check width remains constant regardless of the rotation radius.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the positioning completion width of the rotary axis is given by a fixed angle, then the positioning completion check is simple to implement, but the check width converted into tool tip movement changes in proportion to the rotation radius, causing imprecise positioning determination when the rotation radius is large
Solution Approach 1:
The positioning completion width is made dynamic by calculating it based on the current rotation radius rather than using a fixed angle. The control unit computes the positioning completion width as a linear dimension proportional to the rotation radius, allowing the check width to adapt to different rotational positions and maintain precision across varying rotation radii
Solution Approach 2:
The patent changes the parameter used for positioning completion check from a fixed angular width to a linear width that varies with the rotation radius. By calculating the positioning completion width as a linear dimension (e.g., arc length) based on the current rotation radius, the system maintains consistent positioning precision regardless of the rotation radius magnitude
2Measurement precision
If a small positioning completion width is set to accommodate maximum radii, then positioning precision is maintained for large rotation radii, but the positioning completion check becomes overly strict for smaller rotation radii, increasing cycle time
Solution Approach 1:
The positioning completion width dynamically adapts to the current rotation radius, being larger when the rotation radius is large and smaller when the rotation radius is small. This dynamic adjustment allows the system to maintain appropriate positioning precision for each specific rotational position without using an unnecessarily small fixed width that would increase cycle time
Solution Approach 2:
The patent applies local quality by setting different positioning completion widths appropriate to each local condition (rotation radius). Instead of using a uniform small width across all rotation radii, the system calculates and applies a locally appropriate width based on the current rotation radius, optimizing both precision and efficiency for each specific operational context
Data Source
AI summary
A numerical controller calculates the distance (rotation radius) between the rotation center axis of a rotary axis and a control target point using the machine conditions (including the axis structure and tool length) of a machine tool having a rotary axis and the coordinate values of the respective axes of the machine tool. Then, the preset positioning completion widths of the respective axes are compensated by the calculated rotation radius and a positioning completion check of the rotary axis is carried out using the compensated positioning completion widths.