Vertical injection molding machine PLC technology

Date：2014/7/3 13:13:20

Vertical injection molding machine plastic processing industry is the primary facility, mechanical, electrical, hydraulic wonderful technology in one, in the development of all kinds of plastic heating, melting, mixing, booster, plastic fluid injected into the mold, the completion of a workpiece injection molding. The entire injection molding process through the various electrical components and electrical instrumentation, electrical facilities to control. The traditional vertical injection molding machine crushing discipline is generally accepted by the warring fractions of relays plus temperature control instrumentation is complete, because the relay piecemeal What, then equip bulky, low reliability, maintenance will be detrimental, leading to the fractional precision tubes, flexible control, poor exercise is not intuitive, discouraged easily resolved. To this end, contain finely, and may adopt a strong anti-interference ability, high reliable work, use the guard to facilitate the PLC as its main control component, complete the automatic and semi-passive injection.
An integrated injection molding process
Plastic injection molding granular or powder after the plastic barrel from the hopper into the vertical injection molding machine is heated and melted plasticized, in vertical injection molding machine screw plunger or moving fast but the pressure of being a row compressed and moved forward, the front end of the cylinder via a nozzle at high pressure and injection rate deft closed mold in the lower temperature, the melt filled in the cavity under pressure conditions, solidified by cooling or heating , lost the mold cavity mold corresponding waste. Broken plastic injection molding process involves closing, closing, regulators, the whole feed, injection, holding pressure, pre-plastic, decompression, gate, from mold and other processes.
2 System Design counsel
Vertical injection molding machine system mainly by the trivial, clamping system, hydraulic and electrical control systems and other components discipline, discipline pace from the electrical system output signal to drive the hydraulic system of the task, the hydraulic system gave birth occurred corresponding energy propulsion machinery movement, the machine furnishings movement and response to the hydraulic, electrical system, and actively work together to complete the process of vertical injection molding machine. Among them is the electrical demand factors crushing vertical injection molding machine injection molding raw produce finished, but also flattering vertical injection molding machine fragmented discipline where the overall performance of the link. PLC skills of the traditional use of electrical crushing development transformation, vertical injection molding machine can complete passive and modulating control, injection molding process parameters vocals or bundle also get protection against root. Since PLC bundle approach allows vertical injection molding machine to complete closed-loop control, and that the deviation based online measurement value and set value carried by the negative repercussions loop control, and so when the injection speed, injection pressure, cavity temperature, cavity pressure, melt when parameters such as temperature and oil pressure in the manufacturing process due to the invasion of Health mausoleum presents deviations from the machine can adapt to Britain at the end unrest dragged on for trivial violations of regulatory enthusiastically corrected.
2.1 contain trivial hardware design
2.1.1
Selection PLC applications in accordance to contain vertical injection molding machine, to retreat now active and enthusiastic half cycle control, after the various manufacturers of programmable per-view control is carried out cost analysis, master devices use Omron's CPM2A type. The existence of rich models of PLC instruction aristocratic entertainment city system, fast and satisfactory compliance with the input response pulse input condescend. 40-point I / O type, and one input points accounted for 24 points, accounting for 16 points of input points. Points satisfy trivial applications. And there is a small size, light weight, reliable, strong anti-intrusion techniques and Peixiu convenience benefits.
2.1.2
I / O facilities deployed on the task enthusiastically expounded flowchart development cycle time, which is trivial bundle input devices have peace switch SQ1 and SQ2, limit switch SQ3, SQ4, SQ5, SQ6, SQ7, SQ8, pressure relay contacts KP, active cycle start button and abort button SB1 SB2, determined to work another way switch SA. Implementation of devices collect YV1 ~ YV8 eight solenoid valves. The PLC input point locations 00000-00007 allocated to input facilities SQ1 ~ SQ8, enter the address of 00010 points assigned to the pressure switch KP, 00009 allocated to the input point locations start button SB1, 00100 allocated to the input point locations termination button SB2, input address 00111 deployment decisions to the task another way switch SA. Output to the input point locations 01000-01007 deployment with YV1 ~ YV8.
2.1.3
The output circuit concern measures bundle fragmented vertical injection molding machine PLC hardware design process, thinking to have a DC input termination inductive load, the load is in the middle of a rational power parallel freewheeling diode, freewheeling diode special working voltage is greater than the supply voltage 2 ~ 3 times. In order to withstand the load when a short circuit, PLC lax external input devices, plus the fuse in the input load circuit, short-circuit the development of care.
2.2 Software Design and Implementation
Vertical injection molding machine discipline fragmented sequence yield shown in Figure 3. Because of the containment system has automatic and semi-active both tasks determined another way available. Use the buttons crushing SA (input relay 00111) resolution and a half has been actively working out methods. Now with enthusiastic manner, for example, to describe the specific software design process.
The use of intermediate relay emerge reincarnation process each step, sideways between 20000 relay is energized, the system is in place forms, organizing work. If at this time the switch SQ1 and SQ2 safe route is closed, the relay is energized 20001, 01000 while the output relay is energized, the solenoid valve YV1 split face the task into the "closed mode" step. If the "closed mold" in place, then SQ3 is depressed, energized relay 20002, 01001,01003,01007 input relay is energized, solenoid valves YV2, YV4 and YV8 begin the task into the "closing" step. If the "closing" in place, then SQ4 is depressed, energized relay 20003, 01005 output relay is energized, the solenoid valve YV6 earliest work, enter the "regulator" step. If the "regulator" in place when the pressure relay, the relay is energized 20004, 01007 input relay is energized, the solenoid valve YV8 task split face the very start, enter "into the whole" step. When the "whole into" to SQ5 depressed, 20005 relay is energized, go to "inject" step, 01000 and 01005 input relay is energized, when the solenoid valve YV1 and YV6 start work. Meanwhile TIM00 the end of time, usually between the time t1 the end, go to "dwell" step. "Dwell" while horses face time, often between fixed after t2 is complete, 20007 relay is energized, enter "pre-plastic" step. Solenoid valve YV1 split face the very start the task. "Pre-plastic" to be depressed when SQ6 enter "unzip" step. "Extract" while the end of the time, usually between the time t3 ended, enter the "gate" step. "Floodgates" to SQ7 when depressed, 20010 relay is energized, go to "play mode" step, while the output relay is energized 010001 and 01002, solenoid valves and YV3 YV1 first task.
"Play mode" to SQ8 is depressed, the end of the symbol from the model back to the initial stage of the cycle. In the circulation process, the next step is activated, the previous step is immediately switched off. Display, you can set or modify process parameters vocals, and a fragmented and obstruction warning indicator light display to monitor students build process, thereby greatly advancing the performance parts. The PLC expense discipline less trivial transformation, short construction period, crushing reliability, safety of the road to get Obviously, there will certainly use the advertised value required.
3 Conclusion
The character of the finished product depends on the injection molding machine injection molding process of vertical tubes vocal parameters, traffic patterns mimic Conceiving input variables, such as the temperature of each cylinder, the polymer melt temperature, screw temperature, mold temperature, injection system pressure, screw speed etc.; digital input variable pattern, such as a screw to evacuate the rest position, has an injection seat post, the template and the forward and backward movement over roads. Vertical injection molding machine use PLC skills piecemeal after the defeat of the radical transformation of the open-loop control avenue of harm to achieve closed-loop discipline, another way to make more radical PLC way to contain the anti-invasion mausoleum trick and also has a great level of precision tubes forward. Both can develop logic control switch, can mimic both the amount (such as temperature, pressure, flow, speed, etc.) of the closed-loop control. With keyboard and LCD or digital.

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