Precise control and application of Mitsubishi PLC in press

In recent years, with the improvement of automation technology Precise press application Mitsubishi in Precise press application Mitsubishi China, factory automation also on a new step. Controller of PLC as an emerging industry, with its small volume, complete functions, low price, high reliability, has a unique advantage, won a wide application in all fields. As the nation's largest printing machine manufacturer - northerners group company, in order to make our products stable performance, easy to maintain, we adopted PLC as the control scheme of the host controller. Due to the double color printing machine requirements is easy to operation, high accuracy, so its input and output points more, thus adopted double machine communication. Upper machine adopt mitsubishi FX2N - 80 - Mr 32 ex 4 d/A, mainly responsible for the control of main drive, each unit of the clutch pressure control, as well as the air pump, valve control, etc. A machine under the mitsubishi FX2N - 64 Mr 4 a/D, mainly responsible for the control of water roll motor, main drive speed output, adjustable version of motor data acquisition. Chose a mitsubishi 5.7 -inch touch screen, at the same time is mainly responsible for water roller, according to the motor speed adjustable version, and the machine fault display, etc. The system reliable operation, convenient maintenance, simple and intuitive operation, greatly improve the level of the offset press, is well received by users.

System structure

Among them, the upper machine and lower machine adopted RS485 communication, communication is convenient, and reliable. For multi-color machine, safety factor is very important. In the design, each unit should not only consider the safety control, including the standard unit of scram, security button; Consider convenient operation, each unit shall have excellent, including the button. Therefore, on the one hand, the input point increases a lot; On the other hand, walk line also is not very convenient. Adopts double machine communication, is a good way to solve this problem, the unit can get the line according to the principle nearby, the ark into closer to its control, saves walk the line, is also convenient for control.

Since the printing press is a high mechanical precision, the stand or fall of printed matter is on the one hand, the precision of machining and installation, on the other hand, also depends on the waterway, the balance of ink road, and the accuracy of the pressure. Each color group, two-color machine, there is water and ink device. In order to facilitate water roller speed regulating, each root water roll with a frequency converter control, at the same time, also need inverter to adjust the main motor speed. Therefore, in order to achieve the multi-channel speed regulation, we adopt mitsubishi 4 d/A d/A converter, it would give the digital quantity of PLC, according to the corresponding algorithm, converted into 0 ~ 10 v dc voltage output, well realize the multi-channel speed regulation requirements. In the process of printing, the version is a more complicated process. Especially for multi-color machine, the accuracy of each version for can produce great influence to printing quality. If misregister, print will appear literally overlap or image is not clear. Generally speaking, the plate axial adjustment range is - 2 mm ~ 2 mm, weeks to adjust the range of 1 mm ~ 1 mm. If you are using a manual version, will waste a lot of time, and the accuracy is not high. In order to realize the automatic version, we installed in the version of the roll potentiometer, through the potentiometer to send 4 analog a/D, through PLC processing, version roller rotation accuracy can be well controlled within the scope of the play version.

Touch screen as a new man-machine interface, emerged from a concern, it's easy to use, powerful features and excellent stability makes it very suitable for the industrial environment. User can freely combination of text, button, graphics, digital, etc to handle or monitoring management information may change at any time. With the rapid development of machinery and equipment, the former interface needs to be operated by a skilled operator, unable to improve efficiency. But using a computer interface, can clear instructions and inform the operator of machine equipment's current situation, make the operation simple and vivid. Use the touch screen, still can make machine wiring standardization, simplification, at the same time also can reduce the I/O points required for the PLC control, reduce production cost, is also relatively increase additional value of the whole equipment. Mitsubishi touch screen and mitsubishi PLC has good generality and can on-line monitor and modify the program, don't have to be repeated plug interface of trouble.