Multi-Spindle PCB Drilling Misalignment Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-spindle printed board drilling apparatuses face challenges in maintaining machining accuracy due to axial misalignment of drills, leading to dispersion in hole positions, especially when increasing the number of spindles and varying hole diameters, resulting in reduced precision and potential deviations from intended patterns.
Innovation Solution
A drilling method that involves detecting and compensating for drill misalignment in X and Y directions by adjusting command values for each spindle, allowing for simultaneous drilling of multiple hole diameters while aligning the drill's axial line with the workpiece center, thereby improving overall machining accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple spindles are used to increase productivity, then the number of holes drilled simultaneously increases, but the misalignment of axial lines from designed positions increases due to thermal expansion and air pressure changes
Solution Approach 1:
The patent applies preliminary action by detecting the misalignment of each spindle's axial line from its designed position before simultaneous drilling operations. The control unit stores these misalignment amounts and uses them to correct command values in advance, ensuring that even with thermal expansion and air pressure changes affecting multiple spindles, the actual hole positions remain accurate when all spindles operate simultaneously.
2Adaptability or versatility
If different hole diameters are made by different spindles to handle various hole types, then versatility increases, but the dispersion of machining accuracy increases due to varying misalignment characteristics
Solution Approach 1:
The patent applies local quality by detecting and correcting misalignment for each individual spindle independently, rather than treating all spindles uniformly. Each spindle's axial line misalignment is measured and stored separately in the control unit, allowing customized correction values to be applied to each spindle's command values. This ensures that even spindles making different hole diameters maintain their respective machining accuracies without contributing to overall dispersion.
3Manufacturing precision
If misalignment detection and correction is implemented for each spindle, then machining accuracy improves, but the device complexity increases due to additional detection and control mechanisms
Solution Approach 1:
The patent replaces complex mechanical alignment adjustment mechanisms with a control-based solution. Instead of physically adjusting each spindle's position mechanically, the system uses a detection unit to measure misalignment and a control unit to calculate and apply correction values to the command signals. This substitution of mechanical adjustment with electronic control and software correction achieves high machining accuracy while avoiding the complexity of mechanical adjustment mechanisms for each spindle.
Data Source
AI summary
There is provided a drilling method capable of improving machining accuracy of a printed board drilling apparatus as a whole by decreasing dispersion of the machining accuracy even if it is a multi-spindle printed board drilling apparatus. A misalignment of an axial center of a drill with respect to a designed axial center in X and Y directions is detected in advance per a certain number of revolutions of each spindle that rotates the drill. Holes of two or more types of diameter are made on a printed board by making holes of at least one diameter, e.g., an exposure master hole, per each spindle and by making holes of all other diameters almost simultaneously by all of the spindles.