General composition of control devices for commercial form printers

Commercial form printers are continuous paper printers and their equipment control devices are more complex than sheetfed offset printers. In the actual operation process, understanding and mastering the general composition of the control device, the operator is familiar with the machine performance, skilled equipment operation, reduce operational errors, reduce the rate of production scrap, and strengthen equipment maintenance and prolong the service life of equipment, etc. The important role. Below, the author uses some high-end commercial form printers (such as Japanese palace waist, floating field, Kita Fuji, etc.) as an example, to make a brief introduction to the composition of each part of the control device from unwinding to delivery, and the actual operation process The experience and problems encountered are listed together for reference by peers.

First, automatic tension control device

The function of the automatic tension control device of a commercial form printer is to maintain a constant tension of the web during the entire unwinding process so as to keep the printing rules stable. In the actual printing production, the tension value is generally set to 7-14kg according to the paper type. After setting the automatic tension of the tape, it is generally required to set the manual tension. The setting value of the manual tension should be smaller than the automatic tension setting value. The role of the manual tension is that in the process of the continuous paper, the control device is operated in a jog mode. Tension to prevent excessive tension in the paper causing the joint to break.

Second, the paper joint control device

When the web has a connector through the paper joint control device, the printer should respond to it in a timely manner. There are three general reaction modes:

1, not automatically pressure, only sound and light alarm, prompting the operator through the paper joints, in the delivery of paper should promptly remove the connector.

2, sound and light alarm, automatic pressure. At this point, the impression cylinder is detached from the paper, and the paper strips several meters before and after the paper joint are no longer printed, and the counter stops counting. After the joint passes the machine, the machine will automatically press and print. After the alarm is reset, the audible and visual alarm is terminated.

3, sound and light alarm, automatic pressure, the machine slows down. At this point, the operator must observe the paper joints, wait until they pass through the machine and then manually pressurize, and at the same time speed up the printing.

The paper joint control devices for commercial form printers are equipped with the above three reaction modes. When the device has a low print speed and a small color group, it can be set to the first mode; when the device has more color groups and a higher running speed, it can be set to the third mode; under normal circumstances, it can be set as the first Two ways.

Third, tail detection device

The detection probe of the coil tail control device is installed on the left and right sides of the paper portion on the web, and its control signal is connected to the host. The function is to decelerate the machine when the roll paper is ready to be unwound, and there are 3 control methods:

1. The printing will automatically leave the pressure immediately and the machine will stop automatically after it is reduced to the minimum speed;

2. During the deceleration process, it will not separate from the pressure. After the machine is reduced to the minimum speed, it will automatically leave the pressure and stop automatically;

3. During the deceleration process, the machine is not depressurized. After the machine is reduced to the minimum speed, the machine prints at the lowest speed. The operator can manually stop the machine at any time.

For the above three reaction modes, the operator can set according to actual printing requirements.

Fourth, automatic corrective control device

The purpose of using the automatic deskew control device is to prevent the continuously printed paper from shifting to the left and right. The automatic corrective device has two types of error correction methods: searching for an edge and searching for a line. Commercial form printers generally use the edge search method, that is, there is a positioning probe in the unwinding section to detect the paper edge, and the positive and negative rotation of the correcting motor pull the left and right guide rollers to swing so that the paper always runs along a fixed track. When setting the sensitivity of the automatic corrective device, the paper is generally set to slightly shake the paper, because the sensitivity setting is too high will affect the service life of the corrective device. When the quality of the original paper is too bad and the control range is beyond the corrective control, the automatic corrective device will sound and light alarm. The solution at this time is to rewind the original paper on the slitter.

Five, broken paper detection device

The web break detection probe has a tandem structure. Between each printing color group and the unwinding, processing, and delivery sections, there is a paper break detection device. There is only one way to control the host computer, that is, the machine stops immediately and the sound and light alarm occurs simultaneously. However, when the web break detection probe is covered with dust or shredded paper, the breakage of the paper cannot be detected effectively.

Sixth, automatic oil supply device

The automatic oil supply lubricating device generally has two time settings, namely the oil supply time and the fuel supply interval time. After the running-in period of the equipment is over, the lubricant is automatically applied for 10 seconds every 30 minutes. When the oil in the tank is depleted, the equipment will automatically sound and light alarm.

Seven, circulating water dampening device

Commercial form printers generally use a circulating water dampening device, which not only circulates and filters printing water, but also cools water, and at the same time facilitates the addition of various dampening substances such as alcohol. The circulating water dampening device is an accessory of the machine and has no control connection to the machine itself, but it has a variety of function settings, such as: water temperature setting, over temperature alarm, alcohol proportion display, water pH value display, and the like. In daily printing, its main maintenance is to regularly clean the impurities in the filter. The water temperature is generally set to 10-15 °C. Setting too low will cause the refrigeration compressor to be overloaded.

Each of the above control devices has a greater effect on the operation and use of commercial form printers and on the quality of products.

influences. Grasping the control principle and setting and using methods of each part of the control device has a multiplier effect in reducing downtime, improving product quality, and improving production efficiency.