Tapping Spindle Control With High-Speed Return for Shorter Cycles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Machine tools performing tapping with synchronized spindle and feed axes face challenges in reducing cycle time while maintaining machining accuracy, particularly when the spindle axis rotation speed is set at a relatively low value to accommodate the load on the tapping tool.
Innovation Solution
A control apparatus that includes a numerical control unit to create spindle and feed axis commands, a spindle axis control unit to control rotational operations, and a feed axis control unit to manage feeding operations, allowing for a higher maximum rotation speed during the return operation than during machining, which enables faster return and reduced cycle time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the rotation speed of the spindle axis during machining is set at a relatively low value to accommodate the load on the tapping tool, then the machining accuracy and tool safety are maintained, but the cycle time increases
Solution Approach 1:
The patent segments the spindle operation into two distinct phases: machining phase and return phase. During the machining phase, the spindle rotates at a low speed to ensure machining accuracy and protect the tapping tool. During the return phase, the spindle rotates at a high speed to minimize cycle time. This segmentation allows each phase to operate at its optimal speed without compromise.
Solution Approach 2:
The patent implements dynamic speed adjustment of the spindle axis by changing the rotation speed command value between machining and return operations. The numerical control unit dynamically switches from a first rotation speed command value (low) during machining to a second rotation speed command value (high) during return, optimizing performance for each operational phase.
2Strength
If the rotation speed of the spindle axis during machining is set at a relatively low value to accommodate the load on the tapping tool, then the tool load is reduced, but the productivity decreases
Solution Approach 1:
The patent divides the operational cycle into machining segment and return segment, allowing the spindle to operate at low speed during machining to protect the tool while operating at high speed during return to maintain productivity. This segmentation enables the system to accommodate tool load constraints without sacrificing overall生产效率.
Solution Approach 2:
The patent employs dynamic speed control where the spindle rotation speed is adjusted in real-time based on the operational phase. The numerical control unit switches between a first rotation speed command value (low) during machining and a second rotation speed command value (high) during return, optimizing both tool protection and productivity.
3Speed
If the maximum rotation speed during return operation is set higher than during machining, then the return time is reduced, but the cycle time would increase without proper control
Solution Approach 1:
The patent implements dynamic speed adjustment where the numerical control unit switches from a first rotation speed command value during machining to a second rotation speed command value that is higher during return. This dynamic control ensures that the high-speed return operation actually reduces overall cycle time by compensating for the slower machining phase.
Solution Approach 2:
The patent changes the rotation speed parameter between machining and return operations. The numerical control unit modifies the speed command value based on the operational phase, using a lower speed during machining and a higher speed during return, optimizing the balance between machining quality and cycle time.
Data Source
AI summary
A control apparatus of a machine tool, the control apparatus including: a numerical control unit configured to create a spindle axis command and a feed axis command according to a tapping program; a spindle axis control unit configured to control rotational operation of the spindle axis according to the spindle axis command; a rotation detector configured to detect a rotation position of the spindle axis; and a feed axis control unit configured to control feeding operation of the feed axis according to the feed axis command on the basis of the rotation position. The numerical control unit is further configured to include, in the spindle axis command, a speed command value during return that does not depend on maximum rotation speed during machining of the spindle axis and that is higher than the maximum rotation speed during machining, as a command of return operation.