Abstract: This article introduces the application of Omron NJ controller in the screen printing machine of perfume bottle. After actual testing, the elliptical motion effect meets the customer's requirements. The customers of triangle arc surface and the printing effect of the workpiece with chamfered rectangle are basically satisfied.
Keywords: Omron NJ controller screen printing machine
1 Introduction
Perfume bottle screen printing machine (see Figure 1) is mainly for the perfume bottle, daily necessities and other irregular products on the surface of printing, mostly circular, oval, triangular, square and other diversified shapes. The presses currently used are mostly mechanical cam mechanisms. With the development of science and technology, the printing efficiency and precision of mechanical cams have been difficult to meet market demands. In order to improve the performance of printing presses, Omron has developed an electrical system with OMRON NJ as its core. To meet the market.
Figure 1 perfume bottle screen printing machine in kind
2 system structure and control difficulties
The screen printing part of the perfume bottle screen printing machine is composed of six axes: a rotating shaft, a floating shaft, a mesh plate shaft, a scraping rubber shaft, a feeding shaft, and a connecting shaft, as shown in FIG. 2 . The workpiece is driven on the belt by the feeding shaft (M6), and the connecting shaft (M5) clamps the unprinted and printed workpieces to the printing position and the blanking position, respectively. Rotary shaft, floating shaft, screen shaft, and scraper shaft are used for electronic cam motion to complete screen printing.
Figure 2 Perfume bottle screen printing machine structure diagram
Due to the variety of customer printing products and shapes, such as circular, elliptical, triangular, square, etc., in order to achieve 360-degree printing of workpieces of different shapes, it is necessary to formulate derivation of various shapes of workpieces and calculate the axes of printing. The position of the relationship to do the cam movement, to achieve the printing effect requested by customers, therefore, to determine the relationship between the servo axis during the printing process has become a system of difficulties.
Taking ellipse printing as an example (see Figure 3), in order to ensure the printing quality when printing on the workpiece surface, the scraper needs a vertical printing surface. As the workpiece rotates, the center of the ellipse moves, the scraper needs to move horizontally following the center, and the floating axis moves at the same time so that the printing distance is appropriate. In order to achieve elliptical surface printing, the center of the ellipse of the legend is on the blue line and the doctor blade is in the center. When rotating to the second example, the center is lowered to the orange line and the scraper moves to the right.
Figure 3 Oval printing (the green scraper and the red oval workpiece)
In this system, since not all automation products are Omron's, communication problems with third-party devices are also one of the difficulties that need to be solved. Customers require that simple parameters can be set in the touch screen to change the product for printing. The customer uses a Wei-Lan touch screen with an Ethernet interface. Both the NJ and the touch screen need to be set accordingly. Parameter settings shown in Figure 4.
Figure 4 NJ and touch screen parameter settings
3 system hardware solutions
3.1 System Hardware Configuration (See Table 1)
Table 1 System hardware configuration
Device name
Equipment model
Quantity
1
NJ power module
NJ-PA3001
1
2
NJ four-axis controller
NJ301-1200
1
3
750W servo driver
R88D-KN08H-ECT
1
4
400W servo driver
R88D-KN04H-ECT
3
5
750W servo motor
R88M-K75030H-Z
1
6
400W servo motor
R88M-K40030H-Z
3
7
PLC controller
CP1H-XA40DT-D
1
8
Ethernet Communication Board
CP1W-CIF41
1
9
RS485 communication board
CP1W-CIF11
1
10
Absolute encoder
E6C3-AG5C
1
11
400-750W power cable
R88A-CRKA005SR-E
4
12
400-750W encoder cable
R88A-CRKA005CR-E
4
13
Servo control cable
XW2Z-200J-B34
4
14
Servo terminal block
XW2B-20G5
4
15
ECAT cable
5 meters
4
16
1.5KW servo - Mitsubishi / Yaskawa
Customer specified (price reason)
1
17
750W Inverter - Panasonic
Customer specified (price reason)
1
18
Touch screen - Wei Lun
Customer specified (price reason)
1
19
Input and output modules
I/.O CJ module
Some
3.2 system hardware structure (see Figure 5)
Figure 5 system hardware wiring diagram
4 system software design
4.1 Oval workpiece program derivation
According to the triangular geometric relations, the positional relationship between each servo axis and the rotation axis during the rotation of the ellipse is derived as follows:
According to the above formula in the NJ controller to calculate the axis of the cam data are as follows:
The data of the cam is exported to the SD card for verification. The results are shown in Fig. 6. It can be seen from the figure that the trajectory relationship of the ellipse at the I-IV position is correct, and the motion test can be performed. After the actual printing action test, after testing, the actual movement effect of the servo axis is consistent with the movement trajectory.
Figure 6 Cam Data Verification
4.2 Rectangular workpiece program derivation
According to the triangular geometric relations, the relationship between the servo axis and the rotation axis during the rotation of the rectangle is derived as follows:
Figure 7 Rectangle Workpiece Printing
Figure 8 rectangular workpiece data validation
4.3 Derivation of triangular workpiece program
According to the triangular geometric relations, the relationship between the servo axis and the rotation axis during the rotation of the rectangle is derived as follows:
Figure 9 Triangle Workpiece Printing
Figure 10 Triangle Workpiece Data Verification
Figure 11 Triangle arc data validation
Figure 12 triangle arc surface printing effect
4.4 NJ and Wei Lun touch screen communication settings
(1) NJ uses the default IP address (see Figure 13)
Figure 13 NJ uses the default IP address
(2) Wei Lun touch screen settings - edit - system parameter settings (see Figure 14)
Figure 14 Wei Lun touch screen settings
(3) touch communication address settings (see Figure 15)
Figure 15 Touch Communication Address Settings
Use labels or D0/D2 can be. Here the tag also needs to correspond to the PLC memory address, which is different from the network tag.
5 Conclusion
After inspection by the customer, the elliptical movement effect meets the customer's requirements. The triangular arc surface workpiece and the printing effect of the workpiece with a chamfered rectangular workpiece are basically satisfactory. As the on-site printing conditions are not satisfied, half ellipses, eight deformations, rectangles +
Oval workpieces have not yet been tested. When the customer's mechanical structure such as ellipse, circle, rectangle, etc. satisfies the printing conditions, it will do the accuracy test for the customer.