SK1922023U1 - Method of checking condition of welding electrode tip and system for its realization - Google Patents

Abstract

The method of checking the condition of the welding electrode tip and the system for its realization enables automated inspection of the surface of the welding electrode tip. The computing unit coordinates the positioning system and the laser sensor during fast and detailed scanning of the tip surface, then analyzes this data using the methods of processing point clouds. The system is able to detect deformations, wear and surface imperfections that could affect the quality of the weld. The inspection results are sent to the welding control system, which uses them to decide on the next step in the welding process. Thanks to the designed solution, the need for manual control of the state of the welding electrode tip disappears, which contributes to increasing the degree of automation and making the welding process more efficient.

Description

Field techniques

The technical solution relates to a system for checking the condition of the welding electrode tip, which enables the analysis of the condition of the welding electrode tips. It is used for automatic evaluation of deformations, wear and surface pollution of the welding electrode, which negatively affect the quality of the weld. The system for checking the condition of the tip of the welding electrode belongs to the field of automation of welding processes.

Current state of the art

The current state of the art in the field of automatic inspection of welding electrode tips has revealed some advances, but there is still room for significant improvements. Currently, methods based on visual inspection are often used, which are subjective and limited in their capabilities. Most often, the inspection of the condition of the tip of the welding electrode is performed manually by the worker. Some automated systems have been developed to detect coarser imperfections, but they do not meet the requirements for accurate and thorough inspection. Camera systems that are based on artificial intelligence are in the current state of development and research. But these systems require a large amount of training data to function properly, which can be time- and cost-consuming. In addition, these systems are sensitive to changes in lighting conditions, which can affect their reliability and accuracy. Other camera systems designed to detect faults in welding electrode tips are based on classic color image processing methods. Like AI-based methods, these methods are also sensitive to changes in lighting conditions. An example of such an approach is the document CHISUNG KIM ET AL: Automatic detection of detective welding electrode tips using color segmentation and hough circle detection, November 2016, https://ieeexplore.ieee.org/document/7848238, where the authors use the proposed method for defect detection welding tips of the spot welder.

The essence of the technical solution

Technical solution "The method of checking the state of the welding electrode tip and the system for its implementation deals with the problem of wear and clogging of the welding electrode tip during the automated welding process. The need for automatic inspection of the condition of the welding electrode tip is growing along with the increase in automation in the industry, because the demands on the accuracy and quality of the final products of the automated lines are still increasing. Therefore, it is necessary to automate the processes related to the maintenance and care of the production station itself. The essence of the technical solution is the use of a laser sensor, a computing unit and an automated positioning system, which is equipped with a welding tool with a welding electrode. The positioning system automatically positions the welding electrode in the scanning area of the laser sensor. The computing unit starts the process of scanning the surface of the welding electrode. During the scanning process, the positioning system moves the welding electrode so that its entire surface can be scanned. After completing the movements required to scan the entire surface of the welding electrode tip, the scanned data is transferred to the computing unit. So is the movement data of the positioning system. The combination of data on the movement of the positioning system and data from the laser sensor will be used by the computing unit to perform the necessary transformations, resulting in a 3D digital form (cloud of points) of the surface of the tip of the welding electrode. The generated point cloud is subjected to pre-processing and evaluation using analytical methods designed for point cloud processing. The results of the evaluation are transferred to the control unit of the welding system, which assesses whether it is still possible to continue welding or whether a service intervention is necessary. The result of the welding electrode tip condition inspection system is an assessment of the condition of the welding electrode tip. This means that the system will determine if the electrode is deformed, worn or there are imperfections on the surface of the tip of the welding electrode that could affect the quality of the resulting weld. Thanks to the use of a laser sensor and processing of point clouds, consistent and accurate control of the state of the welding electrode tip is ensured, which is not affected by changes in lighting conditions, unlike systems using camera systems. The use of a laser sensor also brings other advantages in the form of a digitized surface of the welding electrode. This data can serve as input to a welding system maintenance prediction system.

SK 192-2023 U1

Overview of images on drawings

The essence of the technical solution "Method of checking the state of the welding electrode tip and the system for its implementation" is shown and clarified in the drawings, where the components of the technical solution are shown. Figure 1 shows the concept of the technical solution "Welding electrode tip condition inspection method and system for its implementation", which shows the positioning system in the welding electrode tip condition inspection process. Figure 2 and Figure 3 show detailed views from different angles of the process of scanning the surface of the welding electrode together with an illustration of the field of view of the laser sensor.

Implementation examples

An example of the implementation of the technical solution "Method of checking the state of the welding electrode tip and the system for its implementation" is a laser sensor (1) mounted on a stand (5) near a positioning system (4), which performs automated welding using a TIG welding tool (2), which it is equipped with a tungsten welding electrode (3). Before or after the welding process, an automated inspection of the tip of the welding electrode (3) is performed as follows:

The positioning system (4) positions the welding electrode in the field of view (6) of the laser sensor (1). When the positioning system (4) is ready, the computing unit (7), which controls the entire scanning process, sends an instruction to the laser sensor (1) to start scanning. At the same moment, it sends an instruction to the positioning system (4) to start the movement. The positioning system (4) moves the welding electrode (3) during scanning so that the laser sensor (1) can scan the entire surface of the welding electrode (3). After finishing all the movements necessary to scan the surface of the welding electrode (3), the scanning process is finished. Subsequently, the data from the laser sensor (1) is sent to the computing unit (7). The positioning system (4) sends information about the performed trajectory during the scanning process to the computing unit (7). The calculation unit (7) performs the necessary mathematical operations (transformations) to create a cloud of points. The resulting point cloud is further processed by the computing unit (7) and the state of the welding electrode tip (3) is evaluated using analytical methods designed for point cloud analysis. The result of the analysis, i.e. the condition of the tip of the welding electrode (3), which tells about the degree of wear or fouling of the tip of the welding electrode (3), is sent to the main control unit of the welding process (e.g. PLC), which assesses the results based on the requirements for quality and accuracy, whether it is it is possible to continue with the welding electrode (3) in the detected condition or maintenance of the welding electrode (3) is necessary.

An example of a specific embodiment is given only for illustration, not as a limitation of the scope of protection of the technical solution "Method for checking the state of the welding electrode tip and system for its implementation".

Industrial applicability

The industrial applicability of the technical solution "Method of checking the state of the welding electrode tip and the system for its implementation" is significant for companies that provide automated welding with non-melting electrodes. These companies include the automotive, aerospace, energy and engineering industries, where high quality welds are critical for the safety and reliability of the resulting products. The system enables precise inspection and evaluation of electrode tips, which ensures consistent weld quality and minimizes the need for manual interventions, thus contributing to the efficiency of production processes.

Claims (1)

1. A method of checking the condition of the tip of the welding electrode, characterized by the fact that it is carried out in the following steps: positioning the welding electrode in the field of view of the laser sensor using the positioning system; starting the scanning of the surface of the welding electrode with a laser sensor while simultaneously moving the positioning system; transfer of data from the laser sensor and from the positioning system to the computing unit; transforming the received data into a cloud of points; pre-processing and subsequent evaluation of the point cloud using analytical methods of point cloud processing; sending the result of the evaluation of the state of the welding electrode tip to the control unit. 10 2. System for checking the condition of the welding electrode tip, characterized by the fact that it is composed of a laser sensor (1) placed on a stand (5) within the range of the positioning system (4) for scanning the surface of the welding electrode tip (3) installed in the welding tool (2) on the positioning system (4), while the system also includes a computing unit (7) communicating with the laser sensor (1), serving to coordinate the movement of the positioning system (4), processing and evaluating the state of the tip of the welding electrode 15 (3) and transfer of results to the control unit of the welding process.