Friction Stir Welding Z-Axis Correction for Tool Deflection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing friction stir welding methods lack precise control over the Z-axis position of the joining tool, leading to inadequate joining quality on production lines with short required tact times, as they cannot effectively correct for tool deflection caused by reaction forces.
Innovation Solution
A friction stir welding apparatus with a control device that includes a reference setting mode, a joining mode, and a correction mode to measure and correct the position fluctuation of the joining tool in the Z-axis direction, ensuring accurate positioning and alignment during the welding process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If real-time control of rotation speed and traveling speed is implemented to maintain constant joining temperature, then joining quality is improved, but Z-axis position control of the joining tool remains uncontrolled leading to misalignment
Solution Approach 1:
The patent implements feedback control by measuring the actual Z-axis position of the joining tool during friction stir welding and comparing it with the target position. The control device then adjusts the driving device to correct any deviation, ensuring accurate Z-axis position control while maintaining the improved joining quality from temperature control
Solution Approach 2:
The control device is designed to perform multiple functions simultaneously: it controls rotation speed, traveling speed for temperature management, and Z-axis position control for alignment. This multi-functional approach resolves the contradiction by integrating both control aspects into a single comprehensive control system
2Measurement precision
If prediction and correction of Z-axis deflection is incorporated into the control system, then position accuracy is improved, but the required tact time of the production line increases
Solution Approach 1:
The patent performs preliminary measurement of the Z-axis position before friction stir welding begins, establishing a baseline for correction. This preliminary action enables real-time correction during welding without requiring additional time for separate measurement steps, thus maintaining productivity while improving position accuracy
Solution Approach 2:
The control system continuously monitors and adjusts the Z-axis position throughout the welding process without interruption. This continuous correction ensures position accuracy is maintained throughout the entire welding operation without requiring stopping or additional time-consuming intervention steps
3Manufacturing precision
If measurement and correction of position fluctuation is performed during joining, then joining precision is improved, but the complexity of the control system increases
Solution Approach 1:
The patent combines the measurement function and correction function into the existing control device. The control device integrates the driving device control, position measurement processing, and correction operations into a unified system, reducing overall complexity compared to having separate independent systems for each function
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
This solution enables high-quality, high-precision joining of joint target members even on production lines with short tact times by accurately correcting the Z-axis position of the joining tool, thereby improving the reliability and consistency of the welding process.
Implementation Method 1
Friction stir welding (FSW) which joins joint target materials by softening the joint target materials by frictional heat generated by rotating a columnar joining tool
Data Source
AI summary
Provided are a friction stir welding apparatus and a friction stir welding method capable of highly accurate position control in a Z-axis direction (vertical direction) of a joining tool when a joint target member is subjected to friction stir welding by the friction stir welding apparatus. The friction stir welding apparatus includes a joining tool which consists of a shoulder portion and a probe portion and is inserted into a joint target member to rotate, a joining head which holds the joining tool, an apparatus body which holds the joining head, rotates the joining tool, and moves the joining tool, and a control device which controls an operation of the joining tool, in which the control device has a reference setting mode where a correction reference used for correction of misalignment in the Z-axis direction of the joining tool which occurs when the joint target member is joined by the joining tool is set in a stage before the joining tool is inserted into the joint target member, a joining mode where the joining tool is inserted into the joint target member and the joint target member is joined, and a correction mode where an amount of position fluctuation of a tip of the joining tool with respect to the correction reference which occurs when the joining tool joins the joint target member is measured and correction is performed when the amount of position fluctuation exceeds a predetermined threshold value.