I. INTRODUCTION The current production speed of food and beverage filling production lines is very fast. The filling speed of ordinary filling machines has reached 500 bottles/minute. With simple human packaging, such a large amount of packaging work cannot be completed. Therefore, high-speed packaging machines are used in foods. Widely used in the packaging industry. The packaging machine is installed on the production line as a stand-alone device and provides a special conveyor belt to transfer the product lined in the production line to the packaging machine. The packaging machine automatically completes the work of dividing, filming, slitting, heating, cooling, etc. and passes through the conveyor belt. Transfer to the next process. figure 1 figure 2 As shown in the figure above, the products coming from the production line are continuously arranged. The continuous array of products must be divided into discrete product units that can be packaged by a pre-defined film. The following figure will divide the beer cans into every 24 The small unit of one unit of the bottle performs the pretreatment work for the subsequent packaging. image 3 2-S120 Power Module 3-Axis Motor Module 9A 4-Axis Motor Module 5A 5-spindle motor, 1FK7 series 6-minute bottle motor, 1FK7 series 7-minute bottle motor, 1FK7 series 8-delivery motor, 1FK7 series 9-Remote IO, ET200M 10-inverter, MM440, with profibus interface 11-TPP270 Operation Interface 12-Profibus Fieldbus, up to 12M 13-Servo motor power cable 14-Servo Motor DRIVE-CLIQ Encoder Feedback 6. On the film cutting synchronous control: In the film axis and cutting axis synchronization command, set as follows, the imaginary axis cutting_axis, songmo-axis as the slave axis, the imaginary axis xuzhoui_axis as the spindle, select the corresponding cutting_cam, and the songmo-cam curve as the slave axis motion respectively. Track. The master-slave axis operation mode selects absolute coordinate operation, and the Cam operation process selects loop execution. In this way, the upper film axis and the film cutting axis are operated synchronously with the imaginary axis or the main shaft in accordance with a previously set running path.
Second, the introduction of Siemens SIMOTION In the field of motion control, the general motor drive provides a wealth of motion control functions, but the logic control and complex computing functions are quite weak, and the general PLC provides a comprehensive logic control function, but it is difficult to have The full functionality of motion control. The traditional application method is to use PLC and servo controller together, but there are problems such as high-speed data transmission, data synchronization and precise control.
Siemens proposed a new generation of motion control platform SIMOTION. SIMOTION is designed for the machine that plays a leading role in motion control. It integrates logic control and motion control. It can independently perform all the functions of PLC and motor governors in the past. It is mainly applied to those with complicated control requirements and fast control speed. In the field of precision sports.
1. SIMOTION is a simple and flexible control system that integrates motion control, logic control and process control. Has the following advantages:
The combination of logic control and motion control eliminates the need for separate interfaces that affect response time, saves programming and diagnostics for these intermediate interfaces. The programming and diagnostics of the entire machine are not only standardized but also open and transparent like a PLC. The SIMOTION system has three components:
Engineering Development System The engineering development system allows a development environment to solve all motion control, logic and process control issues, and it also provides all the necessary tools, from programming to parameter setting, from testing to troubleshooting.
Real-time software modules These modules provide numerous motion control and process control functions. For the specific functions needed for a particular machine, the relevant modules are flexibly selected.
Hardware Platform SIMOTION D
The functionality of SIMOTION D is integrated into the control template of the new SINAMICS S120 multi-axis drive system, making it a compact system with controllers and drives. Integrate motion control with the driver to give the system an extremely fast response time. SIMOTION D has several specifications, all of which depend on its performance requirements.
III. System Requirements In view of the high degree of automation of equipment in the filling food industry and the characteristics of large product output, the following control requirements have been put forward for high-speed film charters:
1. The speed of operation is high Because of the high filling speed of the food filling production line, the speed of the packaging machine must also reach the matching level. The current mature single-channel plastic film packaging machine can reach the standard output of 50 bags/minute, while the dual channel can reach 100 packets/minute.
2. High reliability In view of the special circumstances of the continuous high-speed production of the production line, any failure of any part of the production line will directly lead to the failure of the entire line, which will bring huge economic losses to the user. Therefore, the reliability of the equipment is required to be very high. The required plastic film packaging machine must undergo rigorous testing before leaving the factory. Continuous production of 2,000 bags per batch, continuous production of 10 batches without any failure as the factory acceptance criteria.
3. Bottle control accuracy
The position between each two cans is only about 20mm. The dividing device must be inserted into this position without any mistakes. Both the front and the back can flip the can top and affect the back package. Before and after the bottle splitter is driven by two different motors, the position and speed must be strictly synchronized, otherwise there will be interference between each other, affecting the quality of the separation bottle.
4. The next process after precise membrane separation is controlled by the upper membrane cutting membrane. The upper membrane cutting membrane must strictly ensure the angle of each membrane, and the angle of the membrane is the same to ensure the integrity of the membrane membrane. If it is a color film package, it must also proofread the cursor of the color film to ensure that the product of the film package is neat, beautiful and of high quality.
5. High product yield Due to the huge output of high-speed film charters, once the equipment fails, it will result in a lot of product waste, and the packaging film is also a one-time product and cannot be recycled. Therefore, the product yield is very high, and the packaging is required. The product is a strict cube that cannot be skewed, left-right asymmetrical, or color-coded asymmetric.
6. High degree of automation When the packaging machine is working, from the beginning of the bottle to the end of the package, all the work is done automatically and no manual intervention is required.
Fourth, motion control system configuration
1. In order to ensure the running speed of the whole machine, the following configuration is adopted:
Servo motor high-speed paper charter machine uses Siemens 1FK7 high-precision synchronous servo motor, the main drive shaft speed is 80 rev / min, the mechanical structure is designed to turn the main drive shaft to produce a package of products, so the maximum output of the single channel design structure It is 80 bags/minute and the standard output is 60 bags/minute, which has reached the production speed of the mainstream high-speed film charter.
High-speed signal processing In the process of machine operation, the response time to key signals is 1MS.
Specific algorithm:
Response time = 1 MS/degree For the above signal directly connected to SIMOTION D435, the response time of SIMOTION D435 input signal is 0.1 ms, which fully satisfies the above requirements.
2. SIMOTION uses an integrated connecting cable and an integrated mounting method to ensure the high reliability of the system SIMOTION's motor and encoder cables all use high-IP-specific connectors, and the user directly plugs the cable connectors in the process. Tighten the corresponding screw on the connector.
SIMOTION adopts an integrated integrated connection mode. DRIVE-CLIQ high-speed communication is adopted between the controller D435 and the driver SINAMICS. The communication speed can reach 100M. The response speed is fast and the integration is good. It is simple and convenient for the user, and the failure rate is low.
Figure 4
The connection between the power unit and the motor driver uses a built-in bronze and DRIVE-CLIQ connection, which is simple and convenient and has a low failure rate.
3. The system configuration uses five 1FK7 servo motors, which are two sub-bottle motors, one main motor, one film motor and one film cutting motor. The main motor power is 3.7KW, the power of the two-divided bottle motor is 0.82KW, the power of the upper film motor is 2.14KW, and the power of the film cutting motor is 1.48KW.
TP270 is used as the man-machine interface of the system.
SIMOTION D435 is used as the master controller.
SIMOTION S120 is used as the motor drive unit.
1-SIMOTION D435 Motion Controller
Fifth, the control principle For the plastic film packaging machine from the cans into the bottle into the package to the finished product out, all the actions are all completed by the machine automatically, completely without manual intervention, the degree of automation is very high. The difficulties in the entire control process mainly exist in the aspects of bottle separation control, output cam control, film control, and film cutting control. SIMOTION provides special functions for all aspects of control, making the original very complex control simple and convenient.
1. Bottle control:
Bottle dispensing control is the most difficult part of the packaging machine control process.
Figure 5
The requirements for dividing bottle control are shown in Fig. 5. The bottle-divider motor M1 controls the bottle-dividers A and C. The bottle-divider motor M2 controls the bottle-breakers B and D. They move in the same direction along the same chain axis. The bottle-divider A, C; The distance between B and D can not be changed, and the bottle dispenser A can not exceed the position of D during the movement. The bottle dispenser D can not exceed the position of C during the movement, otherwise it will mechanically appear stuck. malfunction. When it is required that the bottle divider A arrives at the illustrated position, the bottle separator B also just reaches the illustrated position so that the four bottle products are separated from the subsequent products to achieve the purpose of dividing the bottle. Similarly, bottle splitters B and C also dispense four bottles of the same product at the A and B positions. According to the above process, the cycle is ready for the following dispensing. The distance between the specific A and B determines the quantity of products that can be accommodated in each package. It is required to set the quantity of products that each package can hold through the operation screen. The system automatically calculates the distance between A and B to ensure the normal operation of the machine.
For the above control requirements, the standard multi-axis CAM curve synchronization function provided by SIMOTION is used to precisely control the position of two sub-motors. Specific control methods are as follows:
The position of the fixed spindle motor is used as the X axis of the CAM curve, and the operation positions of the two sub-motors do the Y axis to make two CAM curves, respectively.
As each bottle separator rotates exactly one week, four bags of product can be separated, and the main shaft rotates one cycle to complete the packaging of one package. In order to simplify the system model, the entire production process is divided into the same number of production units, and the entire production process is practical. The same production unit is continuously repeated at the top, and the unit must be completed after the spindle is started in each production unit.
In each production unit, the CAM curve position is synchronized between the bottle-sharing motor and the spindle motor. For each sub-shaft motor shaft, the main motor rotates around 1440 degrees and the motor rotates 360 degrees per week.
The specific control curve is shown in Figure 6, Figure 7
Figure 6 M1 motor CAM curve (units)
Figure 7 M2 motor CAM curve (units)
After the above curve is established, it is specified that the position of Fig. 6 is the zero point of the three motors during the entire curve movement. The divided-motor M1 and M2 will use this position as the zero point to perform strict position synchronization between the respective operation curve and the spindle to ensure Sub-bottle continuous and accurate operation.
Procedure description:
Write the following MCC statement, when the operator presses the "start sync button" to start executing the CAM sync instruction. When the "release synchronization button" is pressed, the release synchronization instruction is executed. The synchronization between the dispensing shaft and the spindle is achieved by the following commands.
In the bottle dispensing synchronization instruction, the following settings are made: dividing the bottle axis fenping1_axis as the slave axis and the main motor drive axis zhudianji_axis as the spindle, and selecting the fenping1_cam curve as the slave axis trajectory. The master-slave axis operation mode selects absolute coordinate operation, and the Cam operation process selects loop execution. In this way, the separate motor runs in synchronism with the position of the spindle according to a previously set operating path.
2. Bottle-stopping correction:
There will be a problem in the process of dividing the bottle: When the bottle-separated motor is put into operation, the system must complete a production unit (the production of four-pack products) and the bottle motor can return to the 0 point coordinate of the curve before it can synchronize the bottle-separated motor with the main motor. Control, otherwise, the position of the sub-bottle motor in the next production unit will be out of sync, which will lead to product waste. Therefore, the following bottleneck control needs to be revised:
As shown in Figures 6 and 7, since the bottle separator is in a cyclic operation, the position of the equipment when the bottle dispensing shaft stops at any one of the five positions of the main shafts 0, 360, 720, 1080, and 1440 for the machinery and equipment Figure 5 is completely the same, so in view of the above situation, we only need to set the event that the stop of the minute bottle is triggered, the system judges which of the above five positions the spindle is in, find the five positions 0, 360, 720, 1080, 1440. The most recent one of the positions is desynchronized. When the synchronizing and stopping of the bottle-disconnect motor is stopped, the current coordinates of the minute-divided motor is cleared to 0. This ensures the strict synchronization with the spindle position at the next start-up. This eliminates the deficiencies in the split bottle control program.
After the above-mentioned corrected machine, the number of packaging errors after the start of separation can be reduced to 1 package, which is a leading position in similar products at home and abroad.
Procedure description:
The following command is set during desynchronization, and the following statement is executed after the release of the synchronization button is pressed. When the spindle reaches the position “fp1_stop_positionâ€, the synchronization is released, and the value of the variable “fp1_stop_position†is judged in real time in the program at 0. , 360, 720, 1080, 1440 value, to ensure that the release of the bottle after the completion of the synchronization axis to the appropriate position.
3. Cam output control:
The equipment control request is to start to judge whether the peripheral equipment meets the operating condition when the main shaft is turned to a certain angle, and if it is satisfied, the control output corresponds to the operation. The standard cam control function will not satisfy the above requirements at the same time, but the system provides the “state†parameter status of the cam. You can use the “state†parameter to create your own control program.
One cam track is established with respect to each function, and the start angle and stop angle of the output are respectively set. The cam starts to output when it reaches the starting angle, and the cam stops output when it reaches the stopping angle.
Procedure description:
The "state" parameter is selected for the output of each cam and then judged, if it is "ON" it means that the cam output, otherwise it means that the cam stops outputting. Then through an intermediate variable to transition the preparation of logical conditions, when the cam output conditions are met to determine whether the peripheral detection device conditions are met, if it is satisfied then the output action.
4. Film displacement control:
The upper film control means that when the spindle motor moves to a certain phase, if the corresponding photoelectric switch is detected, the upper film operation starts. The difference from the above cam output control is that the detection photoelectric switch signal and the phase output are not in the same cycle phase (for example, when the spindle is rotated to 120 degrees, the operation is started, and when the rotation is 150 degrees, the operation is ended. All The movement is all within the range of 0 to 360 degrees of the rotation of the spindle. However, the upper film requires the detection of the photoelectric signal to start the filming operation within two revolutions of the spindle (for example, when the spindle rotates to 150 degrees). When a bottle is detected, the spindle continues to rotate. After this cycle is completed, the film is started at the next turn. That is, after the main shaft rotates 360 degrees, the film motor starts to move and the film moves.
In order to achieve the above functions, a shift instruction is added on the basis of the cam output function, a memory area is set in the program, and the first bit of this memory area is set to operate when the photoelectric signal is detected, when the spindle completes a After the duty cycle (rotated by 360 degrees), the data in this memory area is shifted to the left by one bit, and then the state of the second bit of this memory area is determined by the phase of the start film operation. If it is 1, it indicates that the film operation is currently required. If it is 0, there is no need for filming.
Procedure description:
In the general PLC program to achieve the above functions, we only need to define a word address (such as MW0) as the work address, specify the M0.0 to be set when the upper film signal is detected, and the MW0 is shifted to the left after each rotation of the spindle. In view of the above requirements, only the state of M0.2 needs to be used for logical judgment. The programming is relatively simple.
Since SIMOTION uses variables to store data, it is difficult to implement the above functions by not splitting a font variable into a number of bit-type variables. Therefore, it is implemented using a logical algorithm.
Define a font variable "songmo_delay_inputgdy" to set it by the state of the film photoeye. It is reset by one revolution of the spindle. Then use the OR operation to add its status to the working variable "yiwei_gdy". Perform shift operations.
The shift operation is performed by one revolution of the spindle signal, and then the bit to be judged is taken out by the AND instruction (the state of the variable "tmp_yiwei" is) to determine the state of the variable to be taken out. The system functions have been completed through the adaptation of the above program.
5. Virtual axis synchronization control:
The difficulty in programming the plastic film charter program is how to ensure the synchronous relationship between the film motor and the film motor and the actual sense of the spindle motor; it is required that the film motor be in the process of mechanically packaging a package of products during one rotation of the spindle motor. When the synchronization with the spindle motor occurs during the process, when the synchronous relationship is released; and in order to maintain the integrity of the upper membrane, the membrane motor must also have a process of acceleration and deceleration during the movement. Considering that the length of the spindle motor is set to 0 to 1440 degrees when dividing the bottle, we need the range of 0 to 360 degrees to achieve a relatively simple synchronization because the spindle motor rotates one revolution (360). Degree), the upper film motor shaft and the film cutting motor shaft also move once. Therefore, at this time, we have established an imaginary axis, the imaginary axis and the main shaft are synchronized, and the upper film motor shaft, the film cutting motor shaft and the imaginary axis are maintained at 360 degrees. Interval synchronization. That is, the interval from 0 degrees to 1440 degrees of the main motor shaft is shifted to a range of 0 degrees to 360 degrees.
For the above control requirements, the same multi-axis CAM curve synchronization function provided by SIMOTION is used to precisely synchronize the position of the spindle motor and the imaginary axis:
The position of the spindle motor is used as the X axis of the CAM curve, and the imaginary axis operation position is the Y axis as a CAM curve.
Due to the mechanically mounted film motor, the film cutting motor requires one package per rotation, that is, 360 degrees, and the spindle is set to a length of 1440 degrees. Therefore, in order to simplify the system model, the translation of the spindle to the virtual axis is equivalent to a 360 degree. In the range of degrees, the entire production process actually repeats this same production unit continuously.
The specific control curve is shown below.
Procedure description:
Write the following MCC statement, as long as the CAM synchronization instruction is started when the spindle motor is running, that is, "ping_start_zhuji" is "TRUE" under automatic conditions. The synchronization of the imaginary axis with the spindle is achieved by the following commands.
Make the following settings in the imaginary axis synchronization command. The imaginary axis xuzhou_axis is used as the slave axis and the main motor drive axis zhudianji_axis is the master axis. The xuzhou_cam curve is selected as the trajectory of the slave axis. The master-slave axis operation mode selects absolute coordinate operation, and the Cam operation process selects loop execution. In this way, the imaginary axis will run in synchronism with the position of the spindle according to the preset trajectory.
After the introduction and establishment of the imaginary axis, the imaginary axis is synchronized with the spindle at the time of automatic operation, that is, a 360-degree interval spindle. Therefore, at this time, the synchronization of the film motor, the film cutting motor and the spindle motor is converted into the synchronization with the virtual axis. In accordance with the above control requirements, the SIMMTION provides a standard multi-axis CAM curve synchronization function to the upper film motor shaft and the virtual axis. Precise location synchronization:
Define the imaginary axis position as the X axis of the CAM curve and the position of the upper membrane motor as the y axis to make a CAM curve.
Because the film motor is in synchronization with the spindle motor to maintain the position, the speed needs to be changed to achieve the change of the film's late, early, and upper film length. Therefore, we divide this coordinate system into five segments, namely film feeding. Starting point, film feeding start point, film feeding high speed point, film feeding low speed point, film feeding ending point, and the shape of the film feeding curve can be changed by changing the X, Y axis coordinates of these five pairs of points so as to realize different formulation products Film packaging task.
For the operation of the film cutting motor, the film cutting motor is normally kept in a stopped state. When the spindle motor runs until it needs to cut the film, the film cutting motor stops immediately after a high-speed operation for one week and waits for the arrival of the next cycle. Therefore, the curve is a very The line of "stiffness".
The specific control curve is shown below.
Procedure description:
To write the following MCC statement, start the CAM synchronization instruction as soon as the film signal arrives. The following instructions are used to achieve the synchronization of the upper film axis, the cutting film axis and the imaginary axis, that is, the synchronization with the main axis.
6. Superiority of SIMOTION compared to other similar solutions
1. Compared with the Siemens PLC+MASTERDRIVES MC solution, the Siemens PLC+MASTERDRIVES MC solution represents a very typical type of solution in motion control, that is, the PLC completes the logic operation and data processing functions. The MASTERDRIVES MC completes all the functions of motion control. Compared with the above solution, SIMOTION has very obvious advantages:
High-speed communication interface for isochronous data synchronization SIMOTION D provides a DRIVE-CLIQ communication interface for internal communication. This interface is suitable for communication between SIMOTION D and S120 servo drives, servo motor encoder feedback signals, and communication speeds up to 100M. High-speed data synchronization can be easily realized. High-speed input and output channels SIMOTION D provides a number of high-speed digital input and output channels that can be connected to signals that require high speed response for fastest response.
Integration of integrated programming reduces the difficulty of programming PLC + MASTERDRIVES MC program programmers must be proficient in PLC programming, MASTERDRIVES MC programming and man-machine interface programming. In most cases, it is difficult to fully understand the above three different programming methods.
SIMOTION provides integrated solutions, controllers, drivers, and human-machine interface programs all integrated together and there is a tool for development. As long as programmers understand this tool, they can complete the compilation of three different parts of the program, greatly simplifying the workload.
2. Compared with the B&R control system (PCC) system and servo control (ACOPOS) system solution, the B&R solution represents a typical high-end solution for other brands of servos in the packaging industry. B&R also provides electronic gears. Functions such as electronic cams have some advantages over SIMOTION:
The programming method is simple. The programming language of the B&R controller is C language, which requires the programmer to have a certain level of high-level language programming capabilities. However, it is very difficult for the electrical engineering personnel in the general factory to use C programming. This has caused Equipment maintenance is more difficult.
SIMOTION provides very flexible programming methods, high-level language programming suitable for program developers, ladder diagram programming for engineers, and MCC programming for electricians. In this way, users can use various programming languages ​​according to their familiarity with the tool.
High precision of bottle-breaking control At present, the minimum bottle-breaking unit of B&R's bottle-breaking control is 2 bags (ie, the bottle-separated motor synchronizes with the main shaft, and the synchronization must be completed after the 2 packages are finished).
SIMOTION's minute bottle control unit can reach 1 pack.
Seven, the main monitoring screen Eight, conclusion SIMOTION as a new generation of Siemens motion controller adds a lot of practical functions, reducing the difficulty of the user's programming, in some control requirements of the machine can truly reflect its advantages. The packaged carton packaging machine has been applied on the spot for more than half a year. The application effect is good, and it has received favorable comments from users and equipment manufacturers.