Stepping into the age of tile detection intelligence

China's ceramic tile inspection system has been launched for nearly 20 years since the end of the 1990s. However, fewer than 10 companies have conducted research and development on the ceramic tile. In addition to the high technical requirements, the low penetration rate is also an important factor.

According to incomplete statistics, at present, there are nearly 500 flatness machines used in China and about 100 size machines. Since the tile detection system is mostly placed after the polishing process of the polishing tile, it is calculated according to the national 1400 polished tile production line. China's tile testing equipment has a very broad market prospect.

“The concept of the company itself plays a decisive role in the promotion of the product.” According to Zhang Weiqun, general manager of Foshan Maixun Electromechanical Co., Ltd. (hereinafter referred to as “Meixun Electromechanical”), well-known brand companies have purchased the products because of their product positioning. Product appearance, flatness, color and other appearance requirements are higher, leading manufacturers to increase their investment in quality inspection. At present, famous ceramic companies such as Nobel Ceramics, Champion Ceramics, Ousheno Ceramics, Dongpeng Ceramics, Xinghui Ceramics, Xinruncheng Ceramics, Marco Polo Ceramics, and Shuncheng Ceramics have all purchased and applied such quality inspection equipment. Good response. This is why Zhang Weiqun frankly stated that "after many years of development, our country's tile inspection system is very mature".

Founded in 2009, Mesun Electronics Co., Ltd. has been developing a high-precision ceramic visual inspection system for tiles since 2010, and has obtained national technology patents for dimensional inspection technology. At present, the company sold a total of more than 80 detection systems, and sold to Taiwan, Malaysia, Indonesia, Vietnam and other places. According to interviews, Maisun's electromechanical equipment is currently installed on eight production lines in the Guangdong New School Building Materials Co., Ltd. The company has also developed a microcrystalline stone flatness machine specifically for microcrystalline stone products, and is currently being put into use by companies. The surface frit of microcrystalline stone is prone to wave deformation, so the performance of the flatness machine is very high. The launch of Messon's leveling machine successfully solved the industry's difficult problem of wave deformation detection.

The sizing machine is an automated system that is professionally used for measuring various dimensions of tiles. The system captures the tiles on the production line through the CCD camera, inputs the captured image signals into the computer, and after the computer recognizes and processes the images, it obtains the dimensions of the tiles and determines whether the products meet the quality requirements. If it is unqualified, the alarm light will be on, the alarm will be on alarm, and a note will be drawn on the side (optional device), or a recordable intelligent voice alarm (optional device). The data will also be recorded in the database for statistical analysis.

The size machine can detect many types of products such as polished tiles, full-glazed tiles, antique tiles, ceramic tiles, etc. “This device is particularly suitable for ceramic tile production enterprises.” Zhang Weiqun explained that the tiles on the wall are seamlessly stitched and diagonally The demand is high, and due to the high speed of the production line, traditional manual inspections cannot effectively detect and manage product quality.

The use of the size machine can display online the real-time online display of brick size changes on the production line, after adjusting the edging line in advance to avoid the appearance of excessive size bricks, reduce the loss of excessive standards; online 100% detection of production line products, eliminate product missed detection, timely notification edging line The working conditions are to reduce the occurrence of a large number of excessive bricks due to the failure of the edging line; to reduce the labor intensity of the quality inspection and edging operators. The size machine has also greatly improved the company's quality inspection speed, taking Meysun's mechanical and electrical dimensioning machine as an example. In some enterprises, at least 57 600 × 600 (mm) polished tiles can be detected per minute.

The size machine mainly includes a transmission system, a centering device, a support frame, a sensor, and a vision system.

The vision system is the main component of the size machine, mainly composed of illumination light source, imaging lens group, CCD imaging device and image acquisition system. Its main components are CCD cameras, matching lenses and image capture cards.

Because industrial cameras can accurately detect whether or not the diagonal of a tile is qualified, the CCD camera becomes the main tool for detecting the tile size at the present stage. The CCD has very high requirements on the resolution and field of view of the lens. The choice of the optical lens is critical. It directly affects the quality of the imaging quality and the implementation and effect of the algorithm. CCD has the characteristics of high resolution, small size, light weight, low power consumption, etc. Its shutter speed can reach 1/5000(s), which ensures that the images captured by each camera are consistent in time and reduces the calculation error.

“The key to the size machine is the vision system and system software. To make the size machine run stably, a good match between software and hardware is very important.” Zhang Weiqun’s remarkedly confirmed the importance of “seamless splicing” of hardware and software for device performance. Sex.

First of all, the principle of the vision system is to make the tiles clearly visible on the CCD under the premise of meeting the requirements of the equipment. It images the tile on the CCD. After the positioning sensor issues the tile arrival signal, the CCD scans the tile with the external drive timing provided by the feedback encoder. The acquired image is input to the computer through the image acquisition card for image processing, and the edge length is calculated by a certain algorithm. Dimensional data such as diagonals.

The reporter learned that the visual system is easily affected by dust, water vapor, and temperature in the production environment, so it is very important to choose a component with good quality. At present, most ceramic tile inspection systems in China use imported optical components, which have higher compatibility with software, better technology and better design.

Secondly, the software system is the window for dialogue between the device and the user. It mainly performs the functions of camera control, camera automatic focusing, image preprocessing, algorithm implementation, system control, and data access. The software realizes the basic functions of measurement and provides measurement information such as tile side length, diagonal line, diagonal line difference, current system state and detection speed, measured quantity, qualification rate, etc., and the on/off time, total number of measurements, and unqualified The quantity, qualification rate, quantity and degree of occurrence of various major overshoot types are saved in the form of reports, which facilitates production statistics, management, and timely correction of production equipment such as kilns and edgers.

The key to the realization of the smoothness function of the software design According to the provisions of the national standard GB/T3810.2-2006, the flatness is the general term of the central curvature, the edge curvature and the diagonal warp degree. As long as these three indicators are measured and calculated, and combined with the actual production of the factory, the maximum value of these three values ​​is taken as the value of the flatness of the tested tiles.

Different measurement principles form different measurement methods. The traditional method for measuring the surface roughness of tiles is the feeler gauge method and the dial gauge method. Platform feeler gauge is a direct measurement method, which is the most commonly used measurement method for flatness measurement. Measurement process: Use a bridge frame to measure the position of the workpiece surface, and then use a feeler gauge to measure the gap under the ruler. According to different measurement requirements to select different measurement positions, you can measure the work surface flatness value.

The feeler curvature and warpage degree are measured by the platform feeler method. Due to the limitations of the measurement method, this feeler can only be used for static measurement. The measurement process is affected by the subjective factors of the staff and the measurement error is also large. .

In contrast, the use of a flatness machine can replace manual inspections to achieve 100% complete inspection of online products and eliminate product missed inspections; real-time notification of changes in tile flatness, reminding polishing and furnace operators to adjust process parameters in time; according to more The quality requirements set grading standards in more detail and more scientifically graded products.

The measuring process of the flatness machine is: the tiles are conveyed by the synchronous conveyor belt and adjusted to the correct position by the centering mechanism. When the tile continues to move forward to reach the detection position, it is detected by the positioning switch, and the control system obtains the signal of the arrival of the tile and starts. To perform inspection, the sensor collects the height information of the tile surface, and transmits the measurement data to the PLC. After calculation, the flatness of the measured tile can be obtained.

Zhang Weiqun emphasized that in on-line measurement of tile flatness, whether or not the transport mechanism can make the tiles pass through the inspection station correctly and smoothly is a prerequisite for achieving accurate and accurate detection of flatness; a stable and tight structural design is also very necessary for sensors. Provides good protection against the impact of tiles on the sensor.

"Whether it is a size machine or a flat machine, the design of software can not be ignored for the normal operation of the equipment, and the realization of the free communication and flatness algorithm of the industrial PC is the core of the software design of the flatness machine system." Zhang Weiqun said that the parameter Readings, sending of instructions, reading and accessing of measurement data, etc., are important parts of the online detection software for tile flatness. It is directly related to whether the function of tile flatness online detection system can be realized.

It is understood that few software programs for tile detection systems in China are developed independently. The software algorithm of Maxim's leveling machine was developed by the company's own programmers, and the accuracy of the algorithm was verified through online trial and error. Because of its own software algorithm development, the device can quickly adjust product performance according to customer needs.

Therefore, for the flatness machine, the system software is the intermediate link between workers and equipment. On the one hand, tools need to be provided to allow the user to control the production process parameters according to the quality requirements of the products and provide a numerical display of the test results so that the user can intuitively obtain the flatness information of the tiles; on the other hand, the software needs to generate a certain amount of the parameters based on the user input. The output command controls the detection equipment to perform on-line inspection operations. At the same time, the detection results are displayed in real time. The software must also monitor the status of the flatness detection equipment. If there is an abnormality, the output alarms to avoid improper operation such as wrong inspection or missing inspection, which affects the quality of the product. control.

Accurate, stable, and convenient for ceramic tile detection system to go further In the current high degree of mechanization of the ceramic industry, the ceramic enterprise's requirements for the automation of ceramic equipment, no longer just emphasize automation, for equipment production speed, product quality assurance and production stability Sex has higher requirements. Zhang Weiqun is also aware of this: "An excellent tile inspection system requires stability based on accuracy while being easy to operate."

In the performance characteristics of the ceramic tile inspection system, ceramic enterprises value the ability to eliminate missed products and improve detection accuracy. The requirement of the enterprise to meet the standard of the product size is getting higher and higher. When the traditional worker detects the diagonal line, the allowable error is ±1mm. Now the company requires the error to reach ±0.2-0.4mm. Zhang Weiqun believes that in order to improve the accuracy of the equipment, it is necessary to pay attention to CCD selection, acquisition procedures of control systems, and software algorithms.

At the Guangzhou Industry Exhibition in May this year, many merchants concerned with the ceramic tile inspection system stated that they would give priority to products with guaranteed production speed and stability when purchasing equipment, so as to ensure the stability of the production process. In fact, tile detection equipment can ensure the stability of equipment operation on the basis of improving the detection speed, but the premise is that the hardware and software are reasonably matched.

In addition, because most of the tile detection system programs are extremely complex, once the equipment is debugged, it often occurs that the tuning time is longer than the production time. Therefore, ease of operation is also the direction of future efforts of the device. Mesun Electronics has always been working towards the ease of operation of the equipment. Compared with other similar products, it needs to be debugged for one week before it can be used. Meson's electromechanical products can operate normally after half an hour of debugging.

“In the future, our products will consume shorter time when converting tile specifications; the operation and control of equipment will also tend to be simple.” Zhang Weiqun said that when enterprises convert their product specifications, the equipment will take 15 minutes to adjust some hardware locations and Software algorithm. In addition, because the device has different operation buttons for different steps, the button is usually more than 10, in order to more easily operate the device, the device in the future will reduce the number of buttons.

In exploring how to make the Chinese ceramics industry accelerate the development of automation, many industry experts have shown that the current level of automation in China's ceramics industry is still relatively low, and to increase the level of automation should be based on innovation, the formation of differentiated development It is not simply imitating.

In fact, ceramic automation equipment has developed to a revolutionary breakthrough in technology nowadays. Enterprises have more to upgrade their existing equipment and make automation equipment more technologically mature.

Maisun Electromechanical will improve product performance according to the specific requirements of different customers. At present, the company's tile detection system has been upgraded to the third generation, not only the operation is more simple, but also the product structure more in line with the requirements of the production environment, in order to protect from dust, water vapor, etc., the sealing of equipment components is greatly enhanced.

Some industry experts believe that the future tile detection system will tend to be comprehensive, intelligent and modular. Comprehensiveness means that all product defects can be detected through the equipment; intelligence refers to the ability to adapt to the requirements of manufacturers, improve the software system to improve the performance of the equipment, and modularization means to simplify the appearance and structure of the equipment and make the equipment installation operation more convenient. Simple. "Our size machine will be closer to the modular system, and the installation and use of the system will be more convenient." Zhang Weiqun realized that the simple operation of the equipment is important for ceramic production.

In addition, Zhang Weiqun believes that taking into account the difficulty of manual detection of tile color differences, and susceptible to personal quality and external environment, the error rate when checking is also high, "In the near future, China will also appear tile color difference detection system ."