PCB industry is technology intensive and capital intensive, but it is still labor intensive. A large amount of automation equipment requires manual operation and assembly line work. A medium-sized PCB enterprise has thousands of employees. As the industrial transfer and upgrading, the implementation of the new labor contract law, the economic structure changes bring the rising cost of living in cities, and after 80, 90 staff and liquidity management difficulty, PCB manufacturers are experiencing more and more serious labor shortages and the challenge of rising labor costs, and then bring to the production plan, product quality and profitability. Meanwhile, with the improvement of robot performance and the decrease of price, replacing the traditional production mode of “automation equipment + manual operation” with “automation equipment + manual operation” will become the trend of PCB industry transformation and development.

I. types and characteristics of industrial robots

Industrial robot is a kind of through the repeated programming and automatic control, able to complete certain operations task in the process of producing multi-functional, more degrees of freedom of mechanical and electrical integration of the automatic mechanical equipment and systems, it combines manufacturing host or production line, can be composed of single or multiple machine automation system, under the unattended, implement handling, welding, such as sorting, assembly and painting a variety of production operation.

Since the first generation of robots came into being in the United States in the early 1960s, the development and application of industrial robots have been developing rapidly, and their application in production has been increasingly widespread, which has become an important highly automatic equipment in modern manufacturing industry.

Industrial robot is mainly composed of two parts: body (including mechanical torso, motor, reducer) and electric control (including drive and control system), whose function is to use the actuator at the end to replace hand to grab objects or tools and complete different tasks. At present, there are three mainstream industrial robots, including SCARA(four-axis parallel joint robot), DELTA(parallel robot) and six-axis multi-joint robot (including six-axis multi-joint robot and derived dual-arm robot).

The most remarkable characteristics of industrial robots can be summarized as follows:

1. Programmable. The further development of production automation is flexible automation. Industrial robots can be reprogrammed according to the needs of their work tasks and environmental changes. Therefore, they can play a very good role in the flexible manufacturing process with balanced and high efficiency in small batch and multiple varieties, and they are an important part of the flexible manufacturing system (FMS).

2. Personification. In the mechanical structure, industrial robot has the parts like human walking, waist turning, arm, forearm, wrist, hand claw and so on, and computer in control. In addition, intelligent industrial robots also have many similar human “biosensors”, such as skin contact sensor, force sensor, load sensor, vision sensor, sound sensor, language function and so on. Sensors improve the adaptability of industrial robots to the surrounding environment.

3. Universality. In addition to specially designed specialized industrial robots, general industrial robots have better versatility in performing different tasks. For example, replacing the end operator (hand claws, tools, etc.) of an industrial robot can perform different tasks.

Ii. Application cases of industrial robots in PCB industry

In the early stage, industrial robots were mainly used in the automobile manufacturing industry. In the process of automobile production, they completed welding, assembly, transportation, spraying, etc., which did not require high precision and speed of robots. However, the situation in the PCB industry is relatively complicated. The application of robots in the PCB industry is mainly reflected in the functions of loading and unloading, turning over, sorting, positioning and detection of various processes, and the operation of the PCB board processing equipment and detection equipment should be replaced by manual cooperation. Due to the diversity and complexity of PCB board, there are single-layer board, double-layer board, multi-layer board, flexible board, flexible board, non-porous board and porous board, which leads to more requirements on front-end execution mechanism. There are also requirements on positioning accuracy and working tempo, so the requirements on robotics and integration technology are also higher in the application of industrial robots. After nearly two years of exploration and practice in the industry, we tried to help customers solve problems and meet their needs, and also accumulated industry application experience. At present, we have mature solutions for many process links in the PCB industry, such as AOI, exposure machine, drilling target machine (OPE, XZ), silver paste grouting, text ink-jet, brown prestack, finished product plate, OSP, finished product cleaning, DOME anti-envelop, LCD assembly, etc.

Here are three typical application cases of robots:

1. Six-axis multi-joint robot is used for AOI detection process

Traditional AOI scanning machines rely on manual putting, turning and receiving. One person takes care of two machines, performing repetitive and monotonous actions every day. Moreover, the freshly made circuit board will also emit pungent smell, which will bring certain harm to human body. We use a six-axis multi-joint robot to replace the workers in charge of two AOI’s laying boards, turning boards and receiving boards. Each shift can complete the folding and discharging of more than 700 PCB hard boards, and the comprehensive efficiency can reach 1 piece /min(including AOI machine scanning time). If we can further connect the upper and lower material transport line to AGV for fixed line transfer, we can realize fully automatic production of upper and lower processes.

2. SCARA robot is used in the circuit board coil detection process

The laminated coil short circuit of a complete set of testing equipment, also very few on the market, most of the testing equipment is dependent on human, aperture large PCB board is artificial open board into the testing equipment and test equipment, aperture small PCB board need artificial carrying equipment (probe) to testing for each coil. We use SCARA robot to complete the feeding and feeding and positioning of the detection equipment, so as to realize the one-time detection of all the coils of boards with large aperture. For the boards with small holes, we use SCARA equipment to fix the probe at the executive end, and use the probe to detect each coil by visual positioning. Our equipment also effectively avoids leakage detection due to small or large coil holes during manual operation. Compared with manual operation, the detection efficiency can be significantly improved and quality problems caused by missed inspection can be avoided.

3. The DELTA robot is used for small circuit board finished product packaging process

The existing FPC mounting plates are manually picked up one by one and placed in the blister disc. Since FPC is soft and thin when picked up, the efficiency will be greatly reduced. Delta800 plus a set of visual system can pick out qualified FPC from the messy pile and place them in the blister disc according to the requirements. His speed can reach 60 pieces /min, which can completely replace manual work to carry out sorting and mounting plates.

Third, industrial robot in the PCB industry to replace the advantages of artificial

As with the automobile industry and other manufacturing industries, the replacement of human labor by industrial robots in the PCB industry gives companies many advantages.

1. Reduce employment, speed up work tempo and improve work efficiency. The robot can achieve repetitive operation at high speed and can be far higher than the artificial work beat, which leads to a significant improvement of work efficiency and reduction of labor cost and management cost.

2. Improve operation accuracy and product quality. The robot can use programming and vision system to achieve accurate positioning and repeat accuracy, and effectively improve product quality.

3. Avoid the potential threat of working environment to workers’ health and safety, and save investment in environmental safety.

4. Reduce the decrease of efficiency and quality and the accident rate caused by the effect of repeated and boring processes on the state of workers;

5. Optimize the work flow and reduce the work space.

6. Effectively reduce material consumption rate.

7. Can operate 24 hours continuously and under the environment of black light;

8. Flexible manufacturing process. In the future, there will be more and more orders in small batches in the PCB industry. The use of industrial robots can greatly enhance the flexibility of production and realize the rapid delivery of orders.

9. Improved brand image and reputation. The application of industrial robots further improves the automation level of PCB manufacturers, drives the improvement of product quality, production efficiency, cost control, responsiveness and other aspects, and improves the overall competitiveness of manufacturers in the industry.

Iv. Application prospect of industrial robots in PCB industry

At present, the application of industrial robots in PCB industry is still in its infancy and still faces many problems to be solved. PCB industry many line is a standard product, in the process of robot application subject to the limitations of existing space, is limited by the ability of original equipment, in the face of the influence of different factors in the PCB material, but also promote the intelligent robot, the application of various sensor should also consider for factory training a batch of robot can be operation and maintenance staff.

The future application of industrial robots in the PCB industry will present the following trends:

1. From single station or single line application to multi-line application. It is difficult for existing PCB enterprises to fully introduce robots to realize automatic production, which requires a large amount of investment for transformation. However, they can carry out step by step transformation on the single station and single line with conditions, and then gradually expand the application scope after achieving obvious results.

2. From the application of pure robots to the combination of AGV and other intelligent equipment. Most of the material transfer between existing process production lines is manual operation, which can be distributed and implemented to realize the orderly transfer of materials by combining robot and AGV.

3. The existing plants are mainly applied locally, and the construction of new plants will be planned as a whole, which will be directly imported into the applications of robots and AGV.

4. The combination of industrial robots and Internet of things will make the manufacturing process more intelligent and flexible.