Foreword
• In recent years, China's food packaging technology has developed rapidly. On the basis of the introduction of foreign packaging machinery , domestic machinery manufacturers have greatly improved the level of packaging machinery manufacturing in China by digesting and absorbing, developing and innovating.
• According to the mechanical structure of the packaging machine, food packaging machinery can be divided into vertical packaging machine and pillow packaging machine. As the name implies, the vertical packaging machine is a packaging process from top to bottom. The type of food packaged is generally granules, powders, liquids, such as salt and milk in daily life; pillow packaging machines are flat-packed, packaged food types. Generally blocky, such as instant noodles, sorbet, cakes, etc. Please see the picture below:
Vertical packaging machine pillow packaging machine
This article is mainly based on the pillow packaging machine.
System schematic (economical pillow packaging machine)
Mechanical structure (pillow packaging machine)
Mainly composed of forks, film rolls, color-coded sensors, cutters, and horizontal and vertical seals:
1. The fork is installed on the conveyor belt to mainly transport and separate the packaging. The film roll acts as a film. The color code sensor detects the color code signal on the film. The cutter cuts the packaged package into a package. Since the cutter has a heating device, the cutter has a transverse seal. In addition, the machine also includes a longitudinal seal portion to bond the side film
System Requirements:
• Film roll diameter: 66.88mm
• Cutter diameter: 120.00mm
• Cutter motor ratio: 9:1
• Membrane motor ratio: 9:1
• Cutter rotary shaft external encoder 360 wire • Packing specification: bag length (50-500) mm
• Packing speed: 150 bags / minute • Cutting accuracy: less than or equal to 2.00mm
• Cutter motor power: 700W
• Film feed motor power: 700W
Design Basis:
• Use the pulse signal sent by the PLC high-speed pulse output channel to realize the position and speed control of the servo driver. • Use the high-speed counting channel of the PLC to realize the position feedback of the external encoder. • Use the cutter axis as the main axis and the film inlet axis as the driven axis. Controlling • Position detection with color-coded sensors, PLC position determination, simple position closed-loop control • Derivation design
Calculation method:
• Calculate whether the maximum pulse output meets the requirements. Rev =4096 units/rev
C = D xπ
=66.88 x 3.14159265
=210mm
Vmax = Lmax x PVmax
=500 x 70
=35000 mm/min
Pmax =Vmax / C x Z x Rev / 60
=35000 / 210 x 9 x 4096 /60
=102400
Precision =C / Z / Rev
=0,0057 mm/unit
Derivation conclusion: Accuracy 2mm 〉Precision x 10 Satisfaction condition The maximum output frequency of PLC is 100KHZ, which satisfies the condition
Software design basis (1) Compensation method:
• Due to the cumbersome calculation process, it will not be described in detail here. In short, different packaging speeds determine different pulse output frequencies, compare the actual position detected by each color mark with the theoretical position, compensate according to the difference between the actual position and the theoretical position, and compensate according to the position difference of two thousandths. .
• The actual position value is implemented according to the external encoder, and the actual value is recorded each time the color code is detected. Each package of a pack of cutters rotates one revolution, and the encoder records 0-360 degrees, and is automatically cleared after one cycle.
Software design based on (2) quadrant judgment:
• Since this packaging machine is an economical configuration, the servo has no position closed loop control and no seek function. In view of this, the teaching function has been added to the software: that is, when the color film packaging is performed, if the new packaging specification is replaced, the teaching is performed, and the position value of the first color mark detection is recorded as a post-packaging process. The judgment basis (theoretical position) of the color mark detection.
• During the packaging process, the difference between the position of the color mark detection and the theoretical position is judged. If the difference is greater than 180 degrees, the film feeding motor performs tracking compensation. Otherwise, the film feeding motor decelerates and delay compensation is performed.
• Since the color point position value (theoretical position) at the time of teaching is random, it can be in any quadrant of 0-360 degrees. Because the difference calculation is involved, it involves the problem of forward tracking or delay compensation, so different calculation formulas should be adopted according to the specific situation.
• Here is a brief introduction to the first quadrant:
If 0
If 180
The packaging machine is an economical configuration scheme of the pillow packaging machine, which can not only carry out fixed length packaging, but also can carry out color standard packaging, and the cutting precision is sufficient to meet the requirements of most food processing manufacturers at present, and has been widely used. In the fierce market competition, cost saving is the choice of many manufacturers.
In addition, in the high-end packaging machine, most of the current servo controller closed-loop control. For example, Siemens SIMOTION system: through the motion controller, not only can directly use the system's electronic gear, electronic cam and other process modules for control, but also has superimposed axes, virtual axes and other functions, the system's dynamic performance is higher, positioning accuracy is more accurate.
Product Description
Product name
Black soya beans
Place of origin
Shaanxi, China
Year of production
Crop 2017
Size
6-8.5mm
Moisture
15%max
Admixture
0.2%max
Imperfection
1%max
Packing
25kg or 50kg pp bag
Payment
T/T L/C D/P
Delivery time
Within 20 days after sales contract confirmed
Certificates
CIQ/SC
Shipping
By sea
Black Soy Beans Non-Gmo,Black Soy Beans,Soy Beans,Dry Roasted Black Beans
Ningxia Toyo Trade Co.,Ltd , http://www.toyogoji.com