Machine Tool Servo Current Monitoring for Tool Change Faults
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing machine tools lack effective methods to detect internal abnormalities during tool exchanging operations, such as tool collisions and device breakdowns, which can lead to inefficient operation and potential damage.
Innovation Solution
A machine tool that monitors current values inputted into multiple servo motors to detect abnormalities by comparing them with pre-stored normal time-varying changes during tool exchanging steps, using a current detector and determination unit to identify deviations from expected current patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple motors are used in tool exchanging steps, then the tool exchanging operation can be performed, but it becomes difficult to detect internal abnormalities such as tool collisions and device breakdowns
Solution Approach 1:
The current detector serves multiple functions: it monitors current values for normal operation and simultaneously detects abnormalities such as tool collisions, magazine breakdowns, and tool clamping issues. By making the current detection system multi-functional, the patent enables comprehensive monitoring without adding separate detection devices, thus improving reliability while avoiding increased system complexity
Solution Approach 2:
The system continuously monitors current values from multiple servo motors and provides feedback to the determination unit, which compares actual current values with predetermined threshold values. This feedback mechanism enables real-time detection of abnormal conditions during tool exchanging operations, allowing the system to identify issues such as tool collisions and device breakdowns through current value analysis
2Measurement precision
If current values are monitored during tool exchanging operation, then abnormalities can be detected, but multiple motors make it difficult to identify the specific source of abnormality
Solution Approach 1:
The patent divides the tool exchanging operation into multiple distinct steps (tool unclamping, tool clamping, magazine rotation, etc.), and assigns specific current value thresholds to each step. By segmenting the monitoring process according to operational phases and corresponding motors, the system can precisely identify which specific step and motor are experiencing abnormalities, thereby improving both detection accuracy and source identification
3Reliability
If the machine tool stops operating at abnormal occurrence, then safety is ensured, but productivity is reduced due to frequent stoppages
Solution Approach 1:
The patent replaces the traditional mechanical stoppage approach with an electronic information-based system. Instead of immediately stopping the machine tool upon detecting an abnormal current value, the system records the abnormality information, identifies the specific issue through current value analysis, and enables targeted intervention. This substitution of mechanical stopping with electronic monitoring and information processing maintains safety while reducing unnecessary stoppages and improving productivity
Data Source
AI summary
A machine tool includes a current detector that detects a plurality of current values inputted into a first servo motor and a second servo motor, a storage that stores normal time-varying changes in current values inputted into the first servo motor and the second servo motor in a predetermined step among a series of tool exchanging steps performed between a rotary tool device and an automatic tool changer, and a determination unit that determines whether the predetermined step is performed normally by comparing the plurality of current values detected by the current detector in the predetermined step with the normal time-varying changes in current values.