Application of the hottest baccarat acopos in heat

Application of Baccarat acopos in heat shrinkable film packaging machine

preface

compact dimensions and excellent performance are important requirements for modern servo drivers. There are more than 100000 foam granulating machines, and the drive system of baccalais can not only perfectly match the selected motor, but also meet the requirements of mechanical performance. For applications requiring excellent dynamic performance and positioning accuracy, acopos series also has a very suitable synchronous servo motor. High energy magnetic circuit and patented coil arrangement ensure the compactness of the structure. The application of baccalais programmable controller (PCC) system and servo control (acopos) system in beer packaging production line can fully meet the basic motion control of all motors of the coating machine and the synchronous motion control between them

system configuration and scheme

generally, the film wrapping machine can be composed of six parts: main drive, bottle feeding, bottle separating, paper feeding, film feeding and cutting, and hot channel. According to different design ideas, the mechanical structure of the coating machine produced by various manufacturers is different, and the programmable control system and servo control system selected are also different. Taking a well-known domestic film wrapping machine as an example, this paper will introduce the application of becalay programmable controller (PCC) system and servo control (acopos) system as the electrical control part

1. The hardware mechanism of the coating machine

the servo control system with synchronous electronic gears and electronic cams has long replaced the complex mechanical cam mechanism, which can easily realize the synchronous relationship between moving objects according to the requirements of the designer. Several motion mechanisms of the film wrapping machine use the servo motor as the drive shaft to complete the tasks from bottle feeding, paperboard feeding to film cutting. The main drive using one servo motor will be used as the synchronization object of several other axes, and all the angle and phase relations are also determined according to the main drive motor. Figure 1 shows the approximate position of the five motors in the machine

2. Control system

the servo control system of bekale can fully meet the basic motion control of all motors of the capsule machine and the synchronous motion control between them. The man-machine panel pp41, which integrates the logic control in the packaging process and has the display function, on the one hand, can convey commands and motion characteristic parameters to the motion control part through the input of parameters, on the other hand, it can timely feed back the current machine operation status and alarm status

(1) field bus (CAN bus)

can bus has strong error detection ability and differential drive function, and it still operates well in a very harsh environment with strong noise. Therefore, in terms of media transmission and circuit design, can bus can be easily suitable for most applications

through the connection of field bus (CAN bus), the communication between man-machine panel (pp41) and each servo controller becomes very reliable, especially for the modification of synchronous characteristic parameters in the servo motion control system (Fig. 2)

(2) basic motion control

the servo motion control system (acopos servo) of bekale adopts an object-oriented control mode. Using the high-level language (basic or C) in the automation studio of the development platform of baccalais, as long as an axis object is created for a servo controller, the created pointer can be used to complete different motion control of the motor

basic motion control will be used for the independent commissioning and parameter seeking of each motor of the film wrapping machine, the start and stop of the main drive, and the cooperation of the bottle splitting motor. This control method has clear objectives and is convenient for the preparation of control procedures

(3) synchronous motion control

synchronous motion control is the control of a servo motor to complete a certain motion trajectory relative to another servo motor according to a certain mathematical model, which is commonly referred to as the concept of electronic gear and electronic cam

for acopos servo, the two servo motors involved in synchronization have a master-slave relationship. The synchronous motion control of the film wrapping machine is generally synchronous in position. On the CAN bus, the main shaft will transmit the current position information to the can network at a certain small interval, and the slave shaft participating in the synchronization will also obtain these information in real time, and then calculate the current position of the slave shaft according to the mathematical model in real time, and run the current track

through the mathematical model, we can get the profiler of the slave axis relative to the main axis. The characteristic parameters of these contours should be downloaded to the application sensitive controller of servo controlled converters before the motor participates in synchronization. Pp41 will use can bus to download parameters. Acopos servo can set 11 sets of contour relationships at a time, and use the event method to make the slave axis jump conveniently according to the needs of movement in the set contour relationship group. There are many kinds of trigger events. Pp41 can be used to send four signal messages down, or two trigger messages on the servo controller. Therefore, we can decompose the master-slave contour relationship into several stages (States) according to certain requirements. Through the jump between stages, we can complete the synchronization requirements of different stages

in the film wrapping machine, after receiving the film feeding signal, the film feeding motor starts to move synchronously when the main motor runs to a certain phase again until the main motor completes a cycle, and the film feeding motor also completes a film feeding task. We can divide it into three stages, that is, the film feeding motor waits for the film feeding signal, the main motor reaches the starting phase of film feeding, and follows the main motor to complete a film feeding task. When delivering film, the last stage can be subdivided into several stages according to the principle of "slow before fast"

(4) virtual axis concept

in acopos servo, the moving object created for each servo motor has a virtual axis, that is, virtual axis. This virtual axis is the same as the real axis. On the one hand, it can be used as a slave axis to complete the synchronization track with the main axis. On the other hand, it can also be used as a main axis to allow other slave axes to participate in the synchronization. Due to the introduction of the concept of virtual axis, a servo motor can also synchronize with its own virtual axis

if a main virtual axis is added between the film feeding motor and the main motor, the contour relationship of the three stages of waiting for the film feeding signal, waiting for the starting phase of the main motor, and completing a cycle with the main motor can be added to the main virtual axis. The film feeding motor can be synchronized with the main virtual axis to complete the synchronization tasks of several stages from slow to fast. In this way, when the main motor does not move, let the virtual axis go for a cycle, and the film feeding motor can complete the film feeding task once, that is, manually feed the film once, which is convenient for the adjustment of the film feeding position at the beginning

function realization in the control process

acopos servo's tasks in the film wrapping machine are: driving the bottle pushing rod and film picking rod, feeding paperboard, feeding and cutting film, and separating bottles. Among them, the tasks with synchronous relationship include cardboard feeding, film feeding and film cutting. Figure 3 illustrates the master-slave relationship between several axes. The left side of the arrow is dominant and the right side is subordinate. Although the bottle feeding motor does not participate in synchronization, in the bottle separation process, it, the pressing plate and the baffle are based on the phase angle of the main motor to perform the interrelated start and stop, and jointly complete the bottle separation task

1. Feeding and cutting of white film

film feeding and cutting are the most important links in the film wrapping machine, and also the most difficult part in the control process, especially film feeding

according to the requirements of the process, in the initial stage after the start of film feeding, the speed of film output should be consistent with the speed of a group of bottles to be wrapped, and the part pressed under the cardboard should be of a preset length, and curling cannot occur. In the remaining stages, the film should be quickly removed to ensure that the film pick-up rod can pick out the rear film unimpeded. The speed of these stages of membrane picking must also be controlled appropriately. Too fast will lead to membrane wrinkling, and too slow will cause membrane picking rod to be blocked. No matter how many stages, or how fast the film is discharged in the middle, we must finally ensure that after the main motor executes a cycle, the film feeding motor must also just complete one film feeding. That is, the film feeding motor and the main motor are synchronized once

different manufacturers design different film cutting mechanisms. At present, there are two kinds of mechanisms used more. One is to use an electromagnetic clutch on the film feeding motor shaft to pull in a cutter and rotate it for one circle after binding; The other is to keep the cutter as an independent motor shaft synchronized with the film feeding motor shaft. It is important to cut the film that the instantaneous linear speed of the cutter rotating to cut the film should be greater than the linear speed of the point where the film is cut, otherwise the film may be scratched, cut continuously, and even cause the cutter teeth to collapse. The film wrapping machine of keshimin company adopts an independent cutter motor shaft, and the cutter participating in the synchronization with the film feeding motor can more directly adjust the speed of several synchronization stages during synchronization, ensuring the position accuracy of each film cutting, and can also participate in the color film control

a very important problem should also be paid attention to in the feeding and cutting of white film: film length control under different wrapping speeds. In order to ensure that the film roller will not continue to discharge the film due to inertia after film feeding, a brake device will be added next to the film roller. Affected by the drag factor of the brake device and the friction factor of the film feeding roller, the actual film length will change at different wrapping speeds. In other words, if the one-time film feeding amount of the film feeding motor remains unchanged, the actual film feeding length will become shorter and shorter with the increase of the wrapping speed. Therefore, we need to increase the film feeding compensation at different wrapping speeds

2. Bottle splitting

bottle splitting control in the film wrapping machine has always been a problem that cannot be ignored. The bottle splitting quality of the bottle splitting device will directly affect the subsequent wrapping speed, thus affecting the speed of the whole production line. At present, there are also two kinds of mechanisms used in the bottle separating device. One is to use two motor shafts to keep the synchronous relationship between one fast and one slow with the main motor; The other is to use the pressing plate, baffle and bottle feeding motor shaft to start and stop according to the phase of the main motor. The bottle separation device of the second mode prevents the bottle pouring phenomenon and improves the bottle separation speed

3. Inlet bottle inlet and hot channel bottle outlet

in addition to film feeding and bottle separation, inlet bottle inlet and hot channel bottle outlet cannot reduce the control requirements. Both the inlet and the hot channel should be equipped with a frequency converter to smoothly control the conveying of bottles in and out. According to the requirements of the process, the speed of the inlet conveyor belt and the hot channel conveyor belt should maintain a proportional relationship with the main motor. In this way, the main motor, inlet conveying, bottle separation and hot channel conveying can be basically synchronized. The speed of inlet conveying controls the tightness between bottles, thus affecting the quality of bottle separation. The speed of hot channel transportation and the temperature will also make the film shrinkage after wrapping different. 2. The bolt tension test should be equipped with: a single head bolt should be equipped with a tension bowl (Note: two double head bolts should be equipped with a tension bowl) and a tension ring. Therefore, the synchronous coordination of front and rear conveying is also a factor to be considered

discussion on color film feeding and cutting

white film has no position restrictions, and can start from any position, as long as the film length of each feeding and cutting is consistent. In contrast, the precision required by the position and length of color film feeding and cutting is much higher. In addition to the length of the film, the symmetry of the pattern of the color film after cutting is also a test standard for the degree of the processed sample. Generally, printed