Packaging lines are classified according to the reaction characteristics of the system.
Packaging assembly line continuous control system.
The parameters in the system change are continuous, that is, the system’s signal transmission and the response of the object being controlled is an uninterrupted continuous amount or analog quantity. The previously mentioned temperature control, motor speed control systems are continuous control systems. According to the relationship between the output quantity and the input quantity of the system, the system can be divided into.
Packaging linear control system consists of linear components, each link can be described by a linear differential equation to satisfy the principle of superposition, that is, when multiple perturbations or controls act on the system at the same time, the total effect is equal to the sum of the effects caused by each individual action.
Packaging assembly line non-linear control system in some links with saturation, dead zone, friction and other non-linear characteristics, such systems are often described by non-linear differential equations, does not meet the principle of superposition.
Packaging line intermittent control system
Intermittent control systems, also known as discrete control systems, where the internal signals of the system are intermittent, can be divided into.
(1) Sampling control systems are characterised by sampling devices that sample the continuous analogue quantities being controlled at a certain frequency and send the digital quantities to a computer or CNC device. After data processing or manipulation, the control commands are output. The controlled object is controlled by converting the digital data into analogue data. The sampling frequency is often much higher than the frequency of change of the object.
(2) The control system of a switching control system consists of switching elements. As the switching elements are only “ON” and “OFF” in two completely different states, they do not continuously reflect the changes in the control signal and therefore the control achieved by the system is necessarily intermittent. Common relay contactor control systems, programmable controller systems, etc. are switching control systems. There are two types of switching control systems: open-loop and closed-loop. Open-loop switching control theory is based on logic algebra.
With the increase in automation of packaging assembly lines, the operation, maintenance and routine maintenance of packaging machinery and equipment is more convenient and easy, reducing the professional skills required of operators. The quality of product packaging is directly related to the temperature system, the accuracy of the host speed, the stability of the tracking system, etc.
The tracking system is the control core of the packaging pipeline. Two-way tracking in the front and rear direction is used to further improve tracking accuracy. After the machine is running, the film mark sensor constantly detects the film mark (colour coding) and the tracking microswitch in the mechanical part detects the position of the machine. After the program has been run, both of these signals are sent to the PLC. the output of the PLC controls the positive and negative tracking of the tracking motor, which promptly detects errors in the packaging material during production and makes accurate compensation and corrections to avoid wastage of packaging material. If the technical requirements cannot be met after tracking a predetermined number of times, it can automatically stop and wait for inspection in order to avoid producing waste products; due to the adoption of frequency conversion speed regulation, the chain drive is greatly reduced, which improves the stability and reliability of the machine and reduces the noise of the machine. It ensures a high level of technology in the packaging machine, such as high efficiency, low loss and automatic inspection.
Although the application function of the drive system used on the automatic packaging and assembly line is relatively simple, it places high demands on the dynamic performance of the transmission, which requires faster dynamic tracking performance and high stable speed accuracy. It is therefore necessary to consider the dynamic specifications of the frequency converter and to select a high performance, versatile and high quality converter to meet the requirements of a high-speed continuous production packaging line.