Injection molding machine control system development is changing with the development of the industry simultaneously. In recent years, due to the structural adjustment of the domestic plastic processing industry, the competition between processing enterprises is aggravating day by day. How to reduce the processing cost and improve the processing efficiency has become an urgent issue to be solved by plastic machinery manufacturers. The injection molding machine control system itself, but also should move toward energy saving and environmental protection. Fiber Reinforced Plastics,Glass Reinforced Plastic,Reinforced Plastic,Frp Fiber Hebei Chunfeng International Trade Co., Ltd , https://www.cfcastiron.com
System composition and working principle
1, the conventional injection molding machine proportional control system At present, the vast majority of domestic injection molding machine hydraulic control system using quantitative pump + proportional flow / pressure valve (PQ valve) control. System work, through the injection molding machine control system output analog pressure, flow control signal, the system can achieve pressure, flow of continuous, proportional control. The injection molding machine in the work process, each cycle needs to constantly change the speed and pressure of each action to meet the injection molding process pressure, speed, time control requirements. PQ valve system to meet the injection molding machine open, clamping speed, injection speed, screw rotation, injection pressure, packing pressure, screw torque, ejection force, and other actions of the control requirements, but due to system operation there is more throttling Loss and overflow losses, and thus power loss larger, especially for some packing pressure is higher, holding a long time products, the performance is more obvious. Such as PPR pipe fittings injection molding process, packing pressure is usually 15 ~ 20S as much as ordinary PQ system, a considerable loss of power.
2, the new proportional variable pump system The new proportional variable pump injection molding machine is the application of the proportional variable pump system. This system changed the conventional proportional control method, which was transformed from a quantitative pump + PQ proportional valve system to a proportional variable displacement pump system. Its core control elements adopted multiple compound control functions including proportional pressure, proportional flow rate and load pressure feedback Load-sensitive variable displacement piston pump, the working principle is: the system work, by changing the electrical signal, the displacement of the variable displacement pump parameters (swash plate tilt) to control and adjust, you can provide the system to drive the load Need pressure and flow.
3. Proportional variable pump system's main advantages
The application of proportional variable pump system realizes the transformation of the hydraulic system of the injection molding machine controlled by the valve to the pump control so that the conventional throttle speed control system is transformed into the proportional speed control system and the control performance index of the whole machine has been improved and improved .
In particular, the proportional variable displacement pump system has the following advantages in addition to the advantages of a conventional proportional control system:
â‘ The same power of the machine, injection speed can be increased by 25% or more, more suitable for thin-walled precision injection requirements. As the ordinary PQ system power calculation to hold the state as the standard, proportional variable displacement pump system in this action is very low power consumption, so the pump displacement can be increased by 25% or more.
â‘¡ lower system heat, hydraulic components extend the service life. Proportional variable system almost no throttling, overflow loss, the system greatly reduce the heat when running. Not only can save the consumption of cooling water, low oil temperature greatly increase the life of sealing components.
â‘¢ reduce energy consumption, improve system efficiency. Proportional variable displacement pump system has a good adaptability, the output pressure and flow can be consistent with the load requirements to solve the throttling speed control system does not meet the flow and pressure to adapt to the problem, significantly reduce energy consumption, improve system efficiency, Energy-saving effect is very obvious, compared with ordinary quantitative pump + PQ proportional valve system, saving 25 ~ 45%.
â‘£ NC back pressure control can be achieved, plasticizing effect has been improved.
⑤ reduce the level of pollution of the hydraulic system, system failure significantly reduced, greatly improving the stability of the movement, the use of hydraulic oil longer than the conventional system for more than 3 years.