The self-adhesive labeling machine is the most common type of labeling machine in recent years, and its technology is also improving rapidly. For pharmaceutical manufacturers, higher requirements will be raised, both in terms of labeling production equipment and the self-adhesive labels and bottles to be labeled. Now facing the domestic self-adhesive labeling machine market with mixed good and bad, how pharmaceutical manufacturers can choose self-adhesive labeling machines with higher cost performance will be a concern. This article discusses the key points for selecting a self-adhesive labeling machine from four aspects: main function and control, label feeding speed, printing speed and output, special purposes, and labeling quality.

Overview of self-adhesive labeling machines at home and abroad, their working principles are similar. They are all made of label peeling, transfer and rolling, but their control and manufacturing are different. Generally, a self-adhesive labeling machine consists of a labeling mechanism, a rolling mechanism, a hot stamping mechanism, a conveying mechanism, a transmission mechanism, a frame and a control system. Among them, the rolling mechanism is also divided into a roller rolling method suitable for flat bottles and a rolling seat rolling method suitable for round bottles. At the same time, the self-adhesive labeling machine is divided into vertical and horizontal types according to the bottle status; according to the label delivery speed, it is divided into low speed, medium speed and high speed; according to the characteristics of the container to be labeled, it is divided into round bottles, flat bottles, square bottles, long bottles, etc. (special-shaped bottles) bottles in the pharmaceutical industry); according to the labeling requirements, they are divided into single-sided labels and double-sided labels; according to the label characteristics, they are divided into general labels and transparent labels.

In the past, the labeling position detected by the self-adhesive labeling machine was based on the front edge of the bottle body as the photosensitive point. Because bottles of different diameters require corresponding electric eye movement or labeling time changes, if this is not done Changes will not ensure that the label is in the required position on each bottle. Today's products all come with an "automatic calculation of label length" function, which effectively makes up for the above weaknesses. "Automatic label length calculation" is an automatic control technology formed by combining PLC and servo motor technology. When the bottle on the conveyor belt passes the detection electric eye, the radius of the bottle is measured, and the most prominent point on the outer edge of the bottle is taken as the label. The sensing point of the labeling signal, that is, no matter how small the diameter of the bottle is, the most prominent point on the outer edge of the bottle is the sensing point of the labeling signal. In this way, the distance between the electric eye and the peeling plate does not need to be mechanically adjusted. There is no need to adjust the labeling time at all. This is the automatic control principle of "automatic calculation of label length". This is also people’s first choice for the functions that a self-adhesive labeling machine should have.

In terms of speed control synchronization, in addition to the above-mentioned "automatic calculation of label length" function, the self-adhesive labeling machine should also automatically complete the conveyor belt speed, label discharging speed, label discharging length, etc. Synchronous adjustment is also the difference from traditional self-adhesive labeling machines, and it also guarantees the stability of labeling quality. The control speed of traditional self-adhesive labeling machines relies on human experience for adjustment, and the difficulty in manual adjustment is that all actions are difficult to synchronize. Without synchronization, the labeling process will frequently change, resulting in poor labeling quality.

In terms of control system, the first choice (PLC human-machine interface) control system is the main one. Compared with the early single-chip computer (single-board computer), the use of general-purpose PLC as the main control device can make the PLC The control system achieves the following purposes:

(1) More stable and reliable;

(2) Future maintenance is more convenient and upgrades are simpler;

( 3) It can be easily controlled online with the upper and lower workstations.

In addition, it is also necessary to consider adding a visual system, which can perform real-time detection, control and alarm on the integrity of printing, the condition of character grains, and whether the label after labeling is present and complete. . When choosing a self-adhesive labeling machine, people often only focus on the labeling output (that is, how many pieces can be applied per minute), but fail to comprehensively consider the label feeding speed, printing speed, rolling speed, etc. simultaneously. Of course, labeling output covers other indicators, but other speed indicators play a key role in the quality of use and production development. People can observe the advantages and disadvantages and potential initiative of each organization from its analysis, which is also the choice of self-adhesive. The labeling machine should be comprehensively inspected.

(1) The label delivery speed of the self-adhesive labeling machine. Nowadays, when matching the output of the self-adhesive labeling machine, people often fail to comprehensively confirm based on the label width and printing speed, and only rely on manufacturing It is also unreasonable to choose the maximum output index in the manufacturer's sample, because the maximum output index given by the manufacturer's sample is generally based on a certain label length and a certain printing method. Therefore, when selecting the output of a self-adhesive labeling machine, one should first examine its label delivery speed. Theoretically, the relationship between label delivery speed and labeling output is: Q=1000V/(L a)

Among them: Q is the maximum labeling output calculated based on the maximum label feeding speed, pieces/min; V is the maximum label feeding speed, m/min; L is the length of a single label, mm; a is the spacing between labels, mm.

For example, when labeling a φ36 bottle, L=52mm, a=3mm, V=25m/min, then Q=454 pieces/min. That is to say, when you choose V=25m/min and take into account other factors and the labeling length L=52mm, the maximum labeling output can only be in the range of 400 pieces/min, let alone consider speeding up or replacing longer labels in the future.

In the domestic market, the maximum label delivery speed of general self-adhesive labeling machine products is 38m/min, while companies with technical strength set the maximum label delivery speed of products at 70m/min. This indicator It can be explained that: while ensuring the original labeling output, it can also adapt to label length changes (variable lengths); the high label delivery speed is based on the quality of mechanical hardware, high component configuration and servo control technology, which cannot be produced by ordinary manufacturers. , its value exactly reflects the professional and technical level of the manufacturer.

(2) The printing speed of the self-adhesive labeling machine. For labeling machines used in the pharmaceutical industry, it is particularly important that the label can be printed with the batch number in place. Therefore, when selecting the feeding and rolling speed of the self-adhesive labeling machine, the printing speed of the equipped printer must also be considered. The smallest one can be counted as the actual labeling production capacity value.

In the pharmaceutical industry, the printing of batch numbers on self-adhesive labels is generally based on hot stamping. Hot stamping is a technology that uses a heated prefix to print text through a ribbon. Why is hot stamping the preferred method for printing batch numbers on self-adhesive labels in the pharmaceutical industry? Compared with recent inkjet printing methods, hot stamping has lower production costs and equipment maintenance costs; second, hot stamping does not have the same odor as the solvent emitted by some inkjet printing devices when printing. The circulation of the air conditioning system; the third is that the ribbon can be recycled, which has an environmentally friendly aspect.

Although hot stamping has its own characteristics, it also has a weakness, that is, its printing speed has a certain limit. The fastest speed of domestic hot stamping machines is generally 400 times/min. After this value, printing The text is not clear. Therefore, some people believe that the maximum output of a self-adhesive labeling machine with hot stamping can only be set at 400 pieces/min. Self-adhesive labeling machines with an output of more than 500 pieces/min must be equipped with inkjet printing. When labeling bottles, special-purpose problems are often encountered. For pharmaceutical production, you may encounter: (1) double-sided labeling; (2) similar plastic bottle surfaces due to release agents that cause label adhesion to decrease or There are "bubbles" on the labeling surface. This puts forward more special requirements for the selection of self-adhesive labeling machines.

3.1. Aspects that should be considered when choosing double-sided stickers

If double-sided stickers are required for flat bottles, square bottles, and round bottles, at least the following points should be considered:

(1) The label head can realize multi-dimensional space adjustment to ensure the accuracy of labeling, such as 6-dimensional space adjustment;

(2) The label head adopts a double pressure roller design , to increase the tension of the label to facilitate the labeling of long labels.

3.2. Considerations regarding the problem of "bubbles" being easily generated on the labeling surface

(1) The influence of static electricity should be eliminated. A destaticizing ion blower can be used to electrostatically treat the bottle body. At the same time, use an electrostatic brush to remove static electricity from the label;

(2) Increase the labeling pressure of the label and increase the adhesion between the label and the bottle as much as possible;

(3) Labeling During the process, try to keep the label in line contact with the bottle to completely drive away the "bubbles".

The generally recognized labeling quality requirements are:

(1) Labeling error ≤±1mm, this value can be achieved even if the overlapping position of labeling is repeated multiple times;

(2 ) After affixing, the label and the bottle surface should fit together and be smooth, without wrinkles or "bubbles";

(3) The printed batch number should be clear and legible, without overlap or blurring, and the batch number position error lt;±1mm.

To achieve the above labeling requirements, in addition to label quality and reasonable operation, it is also related to equipment, so the following points should be considered in selection:

(1) Labeling Flatness mainly depends on the reasonable design and high-precision processing of the rolling mechanism. Under the rolling pressure, the line contact between the label and the bottle surface must be ensured;

(2) High configuration requirements of the driving components, Because the core of the label delivery action is a high-precision and ultra-low inertia servo motor, in order to ensure the labeling quality, the system applies closed-loop control, and the motor itself can always correct its own position and compensate itself;

(3) Detection methods and detection components are also the basis for ensuring labeling quality and labeling output. Manufacturers with technical strength have changed the imperfections caused by the past detection components only detecting label printing, and now use detection methods Change to thickness measurement, which uses the thickness change caused by the gap between labels to control the operation of the servo motor. This is currently the best detection method, which is more reliable;

( 4) To achieve perfect labeling, the control of the entire machine is also very critical, especially the bottle feeding speed and label delivery speed. When selecting control, it should be noted that the production speed signal can be sent to the system synchronously, and then sent to the servo motor through analysis and calculation, and the running speed of the two is required to match;

(5) Component configuration, due to today's high-speed paste The standard is based on the continuous operation of the machine, which requires each component to respond quickly and all actions to be completed in an instant, which also imposes requirements on the configuration of detection components. For example, labeling servo motor, labeling motor driver, conveyor belt motor, delivery motor, separation motor, frequency converter, labeling electric eye, label detection electric eye, delivery stop proximity switch, programmable controller, human-machine operation Interface components all have configuration requirements. 5.1. Label selection

The labels used by the self-adhesive labeling machine are all in roll form. The quality of the label will directly affect the quality of the labeling. The die-cutting, slitting, static electricity and dust in the label printing process Processing is also more important.

Note: Features of the self-adhesive labeling machine: Suitable for cylindrical objects such as glass bottles and plastic bottles. Tapered objects can be customized.

A printer or inkjet printer can be installed according to product needs.

Photoelectrically detect bottles to ensure that no bottle is out of the mark;

It can be operated alone or connected to the production line;

The whole machine processing technology is precise and delicate, and the basic The components are all standard accessories, which is convenient for maintenance and repair;

The whole machine is basically imported configuration to ensure the quality, making it more stable, longer in use and lower in maintenance rate