Inverter in sheetfed offset printing application transformation

       Currently, the electrical control of new technology has been widely used in domestic sheetfed offset presses, such as PLC, touch screen, inverter and so on. These new sheetfed offset presses with several years old compared to devices with high reliability, energy efficient, functional, etc., many printing companies in the current, the older models are still sheetfed offset presses has a large number. If they transform the PLC, touch screen all use, the need to change the number of lines, is almost equivalent to re-create the electrical control system. If only for a sheet-fed offset printing press main drive using the drive to transform part of the line change is small, less work. Only retains the original relay contactor control is simple, practical features, and give full play to drive, reliable, energy-saving advantages, cost-effective transformation. Following on the drive in the domestic single-color sheet-fed offset presses transformation application, talk about some experience.

Press operation control process characteristics.

       To make a good inverter drive inverter motor can be applied to printing, to meet the requirements of the production process, we must first clear printing press operation control process characteristics, it has the function of the inverter what demands made, and then choose what type of inverter, as well as how to transform specific docking original lines.

       Sheetfed offset printing operation by the motor through a belt drive, gear drive, chain drive to drive the machine, each roller, tooth row, by a mechanical connection between agencies with the coordination of movements, so the control of the main drive motor on control of the whole machine running. In the mechanical adjustment, inspection, installation and removal PS version and blankets, cleaning machines, will need to manually point forward and reverse drive mode controls the machine running, the speed of about 4r/min more appropriate.

       During the pause in the printing, in order to ensure no damage PS version, the ink does not dry at the same speed to make the machine operate for long vehicles. The machine starts printing the official production, there is an initial velocity of about 3000 rev / hour. When the input speed after the sheet feeding machine starts, the higher production rate of the machine, usually from 6000 to 8000 rev / hour. In order to meet requirements of different production speeds, a speed potentiometer can adjust the speed, the speed actual value can be indicated by the speedometer. From the printing speed is lowered to the printing speed, there are two cases. First, the manual button deceleration, and the other is detected during printing paper faults such as crooked sheets, paperless, double sheets and other press automatically slow down the operation of each part to be made accordingly coordinated action, such as from the pressure, water from Mexico, stop feeding and so on. At the end of production, press stop button, the machine accordingly to freewheel mode gently stopped. In addition, in order to ensure personal safety, the dangerous parts in the printer installed safety switch or the emergency stop button, as long as these switching action, no matter what state the machine, should immediately stop, the whole machine.

       Functional requirements of the inverter

       (1) have a three-speed control, direction control functions to meet the positive and negative points car, forward speed, initial speed printing, high-speed requirements

       (2) the value of the variable speed of high-speed operation, preferably by hand by way of stepless adjustment potentiometer in order to adapt to different process requirements;

       (3) have a machine running speed indicator, so that the operator clear the current operating condition;

       (4) the machine's acceleration, deceleration process should be smooth, speed appropriate to achieve timely and smooth speed change when no shock, the drive itself is faulty when you have to make the whole machine stops.

       Inverter parameters

       According to these requirements shows that the vast majority of the inverter can be met, for the use of the occasion, choose the universal converter. Voltage is selected according to the capacity of the connected power supply and the original machine used by the motor. 400V class used here, monochrome machine 5.5kW, two-color machine 11kW inverter, the inverter on the market a wide range of high quality general choice of the mainstream products, such as Mitsubishi A540 series, Yaskawa G5, Delta, etc. These products, though the price is high, but the quality is guaranteed. For a core component in terms of electric presses, rather into a larger one, to avoid future failures are often caused trouble. Of course, if the inverter other brand of quality, performance indicators are sure, you can choose, so you can save some. With the drive hardware later, to set its internal parameters. On the parameters in terms of speed, jog frequency can be set to 2.5Hz, the initial printing speed 25Hz, 60Hz or so high.