Method and mechanism for accurately controlling heat-seal temperature of heating wire

Abstract

The invention relates to a mechanism for accurately controlling the heat-seal temperature of a heating wire. The mechanism for accurately controlling the heat-seal temperature of the heating wire comprises a first power generation component, a second power generation component, a PLC, a PID module and a PWM controller, wherein the second variable voltage is the PWM direct current voltage; the output end of a second solid-state relay is connected with a Hall current sensor in series and connected with the heating wire; the PID module and the PWM controller are contained in the PLC, the temperature change of the heating wire is worked out by using the PID module of the PLC according to the resistance value of the heating wire fed back by the hall current sensor, and accordingly the on-off time of the second solid-state relay is prolonged or shortened. According to the method and mechanism for accurately controlling the heat-seal temperature of the heating wire, two groups of voltages aresuperposed, the temperature change of the heating wire is accurately detected by the Hall current sensor, the heat-seal time of a film body by the heating wire is further adjusted, the temperature inthe heat-seal process is accurately monitored, and the heat-seal effect is improved, so that the method has the beneficial effect of remarkably improving the product quality.

Description

Technical field: [0001] The invention belongs to a method for controlling an electric heating wire of a bag making machine in the field of bag making machinery, and specifically relates to a method and a mechanism for precisely controlling the heat sealing temperature of an electric heating wire. Background technique: [0002] For a long time, bag-making machines usually use heating wires to cut and seal after heating. Heating wires have the advantages of simple mechanical structure, convenient maintenance and low cost, and are widely used in the field of packaging machinery. At present, in the field of packaging machinery, heating wire is used to seal the sealing line of the film. When the heating wire is heated, the heat is accumulated on the body, and a certain heat capacity is stored. When the heating wire touches the film, the heat will be transferred to the film, and the film seal absorbs heat. Tighten to form a seal or a cut-off, and the temperature of the heating wir...

AI Technical Summary

Problems solved by technology

At present, in the field of packaging machinery, heating wire is used to seal the sealing line of the film. When the heating wire is heated, the heat is accumulated on the body, and a certain heat capacity is stored. When the heating wire touches the film, the heat will be transferred to the film, and the film seal absorbs heat. Tighten to form a seal or a cut-off, and the temperature of the heating wire drops. Under the existing lower production speed, there is not much difference between the electric heating wire power control method using constant pressure heating or intermittent heating; and when it is necessary to increase production Speed, such as 250 or more per second, the processing interval of each bag is less than 240 milliseconds, counting the conveying time, the contact time of the heating wire with the bag is less than 120 milliseconds, due to the fast processing speed, the bag and the The heat transferred between the heating wires needs to be increased. Simply by increasing the electric energy to increase the temperature of the heating wires, it is easy to cause the instantaneous temperature to be too high and the sealing of the film to become sealed or the quality of the sealing to deteriorate. method, because the power supply equipment uses a core-coupled transformer for on-off changes, there will be a defect that its response time is higher than the processing cycle, coupled with the influence of the eddy current of the transformer itself, the response speed is too high, the intermittent time is inaccurate and it is difficult to control accurately , and the use of switching power supply also has the problem of using ultra-high energy control parts. The use of current devices cannot output accurate voltage. At the same time, increasing the amount of energy means increasing the output current and voltage. The heating wire generally uses low-voltage (15-36v) DC To increase the output, it is necessary to select a super-high-standard current controller, which is also unrealistic in actual use. Therefore, the current heating wire has the technical problem of difficult and precise temperature control, which leads to unstable film sealing.

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