The lack of size or inaccurate dimensions of the carton has always been a quality issue in the drum die cutting. The demand for the packaging industry is getting higher and higher, which makes it difficult for a carton with poor accuracy to pass through automated packaging lines. Some manufacturers use variable speed motors and other equipment, irregularly adjust the speed of the bottom drum to make it consistent with the linear speed of the die drum, but in the waste rate control, machine time savings, manpower savings, carton high precision tolerance requirements This passive approach does not completely solve the problem.
Fortunately, the well-developed DICAR equalizer (Equalizer) has provided the best solution for this purpose. Main Factors Affecting Accuracy In order to understand how to maintain dimensional accuracy, it is important to first understand the main factors that cause carton dimensional changes. Under normal operating conditions, there are four influencing factors:
First, it is the height of the drum die cutter, which is determined by the machine manufacturer and then executed by the die cutter.
The second is the theoretical diameter of the die.
The third is the cutting depth of the roller knife on the bottom rubber pad. Most machine manufacturers recommend a standard plunging depth as the ideal setting, but it can change for different orders. The depth of cut depends on the operator and usually requires a sufficient depth of cut to achieve a thorough cut through the cardboard with a slight margin.
Finally, the surface speed of the bottom drum will normally decrease as the bottom pad wears. Surface Speed ​​Ideally, the surface speed of the die, the surface speed of the bottom drum, and the running speed of the corrugated cardboard should be the same.
Unfortunately, under conventional drum die-cutting conditions, this situation exists for only a short period of time, when the bottom pad is completely unworn and therefore the upper and lower drums operate at the same rate of 1:1 theoretically. From this point on, the bottom pad wears out, which reduces the diameter of the bottom roller, and thus changes the surface speed of the bottom roller, eventually resulting in a shortened length of the carton. The surface speed of the die depends on the circumference of the drum to the radius of the blade. The surface speed of the bottom drum depends on the circumference of the radius from the center of the bottom drum to the bottom pad surface. Due to the wearability of the bottom pad, it is obvious that the only variable that cannot be kept constant here is the surface speed of the bottom roller. Therefore, it has been difficult to ensure the accuracy of the cartons from beginning to end under repeated orders. It is hard to care when customers request to run a multi-carton carton. Two or more carton boxes are cut from one piece of corrugated paper and the size problem becomes even more obvious. In order to control the size of the first carton, the cutting depth of the die cutter or the speed of the bottom drum must be changed. However, this will inevitably change the size of the last carton. In general, the last carton will be cut shorter than the first one. Experience shows that if you try to control this phenomenon, you will change the size of the first carton. This is called "difficulty." This effect makes batches of finished products inconsistent due to differences in carton size, machine size, drum speed, and depth of cut of the knife. Many carton manufacturers have made valuable efforts to solve this problem and found many ways to minimize the dimensional changes caused by die cutting by the rollers. One method is to use a variable-speed bottom roller. The tolerance of the carton is measured by the operator from time to time. The operator then adjusts the speed of the bottom roller through a variable speed motor to compensate for the wear of the bottom pad. Short diameter. The system can achieve certain results, but the carton factory must rely on the operator's technology to make the right adjustments. Even in this case, it is difficult to accurately determine the diameter of the undercushion, because in most cases, the wear of the underpad is different everywhere. In many cases, this also gives the operator too much trouble, often causing damage to the die and gear system. In addition, in the case of multiple editions, some of the modellers make the second board longer to compensate for the size difference between the "end to end". Although these methods can solve some problems, they cannot fundamentally meet the needs of customers with high precision requirements, and it is difficult to meet the ISO9000 standard. The DICAR equalizer DICAR uses a system called an equalizer to control the surface speed of the bottom drum to reduce operator error. Unlike standard die-cutting devices, the bottom pad does not cover the bottom roller directly, but instead fits over the bearing sleeve (figure 05).
No matter how the diameter of the bottom rubber pad changes, the bearing can slide freely on the bottom roller, so that the surface speed of the bottom pad is completely controlled by the cutter die, so that the shape of the die cut carton and the cutter die are exactly the same. The main progress made by the equalizer in controlling the size of the carton is that it does not require the involvement of the operator, and it is not necessary for the operator to adjust the rotation speed of the drum at regular intervals. Instead, it is automatically adjusted by the equalizer. This is very important when cutting orders repeatedly. Because customers of course want the exact size of each shipment. Based on this, when running multiple plates or multiple sets of molds, there will be no end to end phenomenon. The shape of the die-cut carton will be exactly the same as the corresponding mold. In addition to this advantage, the DICAR equalizer has the following advantages: It extends the life of the bottom pad. Because the line speeds of the upper and lower rollers are completely the same, the tension of the bottom rubber pad is reduced. In addition, the diameter of the knife mold and the diameter of the bottom rubber pad do not have to be the same, so that the cutting point of each roller knife is uniformly moved on the bottom rubber pad, ie, Each time it does not fall on the same point, the bottom pad wears very evenly and lasts longer. The application proves that the life of the bottom pad on the equalizer can be extended by more than 30%. Replace the bottom pad shorter time. The position of the traditional bottom pad needs to be removed and then installed. The replacement of the bottom pad of the DICAR equalizer is very convenient and takes only 5 minutes. The savings in downtime are considerable.
At present, more than 1,000 rotary die-cutting machines in the world are equipped with DICAR equalizers. This patented product enables unprecedented precision in the size of cartons and saves a lot of machine time and manpower. Hongye Equipment Co., Ltd. Lu Xiangqian