Machine Tool Reaction Force Compensation for Machining Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional machine tools face reduced machining accuracy due to displacement of the tool caused by machining reaction forces, which is not accounted for in positioning control, especially when using soft and low-rigidity tools like elongate end mills, leading to inefficiencies in machining time and accuracy.
Innovation Solution
Incorporating a reaction force detecting unit, displacement amount calculating unit, and compensating unit into the machine tool to detect and compensate for the displacement caused by machining reaction forces, allowing for precise position control and eliminating the need for gradual cutting or slowdown of the feed device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional positioning control is used without considering machining reaction forces, then the control system remains simple, but machining accuracy deteriorates due to tool displacement
Solution Approach 1:
The patent implements feedback by detecting machining reaction forces and using this information to calculate and compensate for tool displacement. The reaction force detecting unit continuously monitors forces during machining, and the control unit uses this feedback to adjust positioning commands, creating a closed-loop system that maintains machining accuracy despite tool displacement.
Solution Approach 2:
The patent replaces purely mechanical positioning control with a hybrid system that incorporates force detection and computational compensation. Instead of relying solely on mechanical rigidity and positioning precision, the system uses reaction force detection and algorithmic displacement compensation to achieve accurate machining.
2Manufacturing precision
If gradual additional cutting processes are used to mitigate tool displacement effects, then machining accuracy improves, but machining time increases
Solution Approach 1:
The patent applies preliminary action by calculating and compensating for tool displacement before it affects machining accuracy. The system proactively adjusts positioning commands based on predicted displacement from reaction forces, preventing accuracy degradation rather than correcting it after the fact through multiple cutting passes.
Solution Approach 2:
The patent enables skipping the traditional gradual cutting process (rough finishing, semi-finishing, finishing) by directly compensating for tool displacement in real-time. This allows the system to perform single-pass machining at optimal feed rates while maintaining high accuracy, eliminating the need for multiple sequential cutting stages.
3Productivity
If feed device acceleration is maximized to reduce machining time, then productivity improves, but positioning accuracy deteriorates due to uncompensated tool displacement
Solution Approach 1:
The patent uses real-time feedback from reaction force detection to continuously adjust positioning commands during high-speed machining. This allows the system to maintain positioning accuracy even when operating at maximum feed device acceleration, as the compensation adapts dynamically to changing force conditions.
Solution Approach 2:
The patent implements dynamic compensation that adapts to changing machining conditions in real-time. The reaction force detection and displacement calculation systems continuously update compensation values based on current cutting forces, enabling accurate positioning during dynamic high-speed operations rather than relying on static pre-calculated compensation.
Data Source
AI summary
A machine tool has a holding portion, spindle, feed device, controller generating a position control signal according to machining data and controlling a feed motion of a drive unit according to the position control signal, reaction force detecting section for determining a reaction force the tool receives from the workpiece during machining, displacement amount calculating section for determining displacement of the tool with respect to a target control position based on the reaction force, and compensating section receiving the displacement amount and adding correction data for eliminating the displacement amount to the position control signal or the machining data.