3D Optical Referencing Between Tool Holder and Workpiece Support
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current machine tool measurement techniques are inadequate for accurately determining the three-dimensional relative position between a tool holder and a workpiece support, particularly due to limitations in measuring tool wear and thermal variations, and often require multiple measurement steps, increasing costs and implementation time.
Innovation Solution
A machine tool equipped with an optical measuring device featuring a three-dimensional target with a planar reference face and an inclined face, allowing for simultaneous three-dimensional measurement of the relative position between the tool holder and workpiece support using a single shooting step, utilizing a dual-camera system with different focal lengths and reflection properties to capture precise images without the need for focusing adjustments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional measurement techniques are used to measure relative position between tool holder and workpiece support, then measurement can be performed, but measurement precision is degraded due to tool wear and thermal variations
Solution Approach 1:
The patent introduces a target object as an intermediary element that is attached to the tool holder. This target object serves as a stable reference that does not wear like the cutting tool and can be precisely tracked by the optical measurement device, thereby mediating between the tool holder and measurement system to achieve high precision and reliability
Solution Approach 2:
The patent creates an optical copy or image of the target object using the optical measurement device. By measuring the position of this optical image rather than the physical tool directly, the system achieves measurement that is independent of tool wear and thermal expansion of the machine structure
2Measurement precision
If two-dimensional measurement is used for relative positioning, then implementation is simpler, but measurement precision is insufficient for complete three-dimensional positioning
Solution Approach 1:
The patent transitions from two-dimensional measurement to three-dimensional measurement by using an optical measurement device that can capture depth information. The optical system measures not only X and Y coordinates but also Z coordinate (distance along optical axis) by analyzing the image of the target object, thereby achieving complete three-dimensional positioning
Solution Approach 2:
The optical measurement device performs multiple functions: it measures both two-dimensional position (X, Y) and three-dimensional distance (Z) using a single system. The same optical device that captures the image also provides depth information through focus analysis or stereo vision, eliminating the need for separate measurement systems
3Measurement precision
If multiple measurement steps are used for three-dimensional measurement, then measurement completeness is improved, but productivity is reduced due to increased measurement time
Solution Approach 1:
The patent combines multiple measurement functions into a single optical measurement step. The optical measurement device simultaneously captures position information in X, Y directions and distance information in Z direction by taking one image of the target object, thereby merging what would traditionally require multiple measurement steps into a single operation
Solution Approach 2:
The target object is pre-attached to the tool holder during tool setup. This preliminary action ensures that the target is already in its final position, so when the optical measurement is performed, no additional positioning or adjustment steps are needed, allowing immediate three-dimensional measurement
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables rapid and precise three-dimensional relative position measurement between the tool holder and workpiece support, overcoming tool wear and thermal variations, and reducing measurement time and complexity by capturing images in a single step, achieving accuracy of one micrometer or less.
Implementation Method 1
a first structure defining a planar reference face distributed between at least: a first portion whose surface is reflective according to a diffuse reflection, and a second portion whose surface is reflective according to a specular reflection
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
The invention relates to a machine tool comprising a machining module (300) equipped with a tool holder (310) and with a workpiece support (320), and an optical measurement device (10) for the three-dimensional measuring of the relative position between the said tool holder (310) and the said workpiece support (320), the said optical measurement device (10) comprising an optical system (100) mounted on the workpiece support (320) and a target (200) mounted on the tool holder (310) and comprising a working face (202) forming a positioning reference that can position itself on the optical axis (O) of the optical system (100).