本文设计的真空吸鱼泵控制系统,采用水环真空泵产生负压,设计了一套基于伺服进行精准位置控制的四通阀装置,实现了吸鱼和排鱼过程的高效切换,提高了吸鱼效率、降低了在捕捞输送过程中对渔获的损伤。整机控制系统基于PLC 控制模块为核心...本文设计的真空吸鱼泵控制系统,采用水环真空泵产生负压,设计了一套基于伺服进行精准位置控制的四通阀装置,实现了吸鱼和排鱼过程的高效切换,提高了吸鱼效率、降低了在捕捞输送过程中对渔获的损伤。整机控制系统基于PLC 控制模块为核心、配置了现场操作的触摸显示人机界面,并通过组态技术,从端到云构建了在 Web 端和移动端对装备进行监控的系统,实现了对装备的本地和远程监控。展开更多
Vacuum die casting is the optimal method to produce high quality aluminum alloy components.At present,there are still very few systematic studies on vacuum die casting theory and equipment design.On the basis of the e...Vacuum die casting is the optimal method to produce high quality aluminum alloy components.At present,there are still very few systematic studies on vacuum die casting theory and equipment design.On the basis of the existing theories of the vacuum die casting pumping and venting systems,a simplified model is established in this research.The model has an aggregate unit consisted of ＂vacuum pump ＋ buffer tank＂ and a cylindrical container（including the shot sleeve,cavity and exhaust channel）.The theoretical analysis is carried out between the cavity pressure and the pumping time under different volume models.An auxiliary system for high vacuum die casting is designed based on the above analysis.This system is composed of a vacuum control machine and a new vacuum stop valve.The machine has a human-computer control mode with ＂programmable logic controller（PLC） ＋ touch screen＂ and a real-time monitoring function of vacuum degree for buffer tank and die cavity.The vacuum stop valve with the ＂compressed gas ＋ piston rod ＋ labyrinth groove＂ structure can realize the function of whole-process vacuum venting.The new system shows great advantages on vacuuming the cavity with a much faster speed by making tests on an existing die casting mold and a 250 t die casting machine.A die cavity pressure less than 10 kPa can be reached within 0.8 s in the experiment and the porosity of castings can be greatly decreased.The systematic studies on vacuum die casting theory and equipment have a great guiding significance for high vacuum die casting,and can also be applied to other high vacuum forming in related theoretical and practical research.展开更多
文摘本文设计的真空吸鱼泵控制系统,采用水环真空泵产生负压,设计了一套基于伺服进行精准位置控制的四通阀装置,实现了吸鱼和排鱼过程的高效切换,提高了吸鱼效率、降低了在捕捞输送过程中对渔获的损伤。整机控制系统基于PLC 控制模块为核心、配置了现场操作的触摸显示人机界面,并通过组态技术,从端到云构建了在 Web 端和移动端对装备进行监控的系统,实现了对装备的本地和远程监控。
基金supported by Fujian Provincial Natural Science Foundation of China (Grant No.2007J0170)Xiamen Municipal Natural Science Foundation of China (Grant No.3502Z20093034)
文摘Vacuum die casting is the optimal method to produce high quality aluminum alloy components.At present,there are still very few systematic studies on vacuum die casting theory and equipment design.On the basis of the existing theories of the vacuum die casting pumping and venting systems,a simplified model is established in this research.The model has an aggregate unit consisted of ＂vacuum pump ＋ buffer tank＂ and a cylindrical container（including the shot sleeve,cavity and exhaust channel）.The theoretical analysis is carried out between the cavity pressure and the pumping time under different volume models.An auxiliary system for high vacuum die casting is designed based on the above analysis.This system is composed of a vacuum control machine and a new vacuum stop valve.The machine has a human-computer control mode with ＂programmable logic controller（PLC） ＋ touch screen＂ and a real-time monitoring function of vacuum degree for buffer tank and die cavity.The vacuum stop valve with the ＂compressed gas ＋ piston rod ＋ labyrinth groove＂ structure can realize the function of whole-process vacuum venting.The new system shows great advantages on vacuuming the cavity with a much faster speed by making tests on an existing die casting mold and a 250 t die casting machine.A die cavity pressure less than 10 kPa can be reached within 0.8 s in the experiment and the porosity of castings can be greatly decreased.The systematic studies on vacuum die casting theory and equipment have a great guiding significance for high vacuum die casting,and can also be applied to other high vacuum forming in related theoretical and practical research.
