压边力控制技术研究现状

Research status of blank holding force control technology

压边力控制技术(BHFT)是大型覆盖件成形和先进成形设备制造的共性关键技术之一。BHFT涉及液压元件制造、自动控制、成形工艺以及成形装备等诸多技术领域,是制约冲压生产的重要因素,也是板材成形领域的研究热点和难点。从理想压边力行程曲线、加载模式、压边力随行程或区域变化以及控制方式和方法等方面,综合分析了国内外BHFT研究现状。对BHFT提出了按传力介质和加载与耗能方式的不同进行分类的方法,并将磁力压边归入以磁性材料为传力介质的压边方法。对压边过程中的受力情况进行了分析和分类,定性分析了不同压边方法的能耗。指出了在拉深成形过程中,用于抑制板坯起皱所需要的压边力做功很小,采用电控永磁压边的内力加载方式可显著降低能耗和减小设备吨位,可望为BHFT的发展开辟一种新途径。

Blank holder force control technology(BHFT)is one of the common key technologies for large-scale cover forming and advanced forming equipment manufacturing.BHFT involves many technical fields such as hydraulic component manufacturing,automatic control,forming process and forming equipment,and it is an important factor that restricts stamping production and also a research hotspot and difficulty in the field of sheet forming.The research status of BHFT at home and abroad was comprehensively analyzed from the aspects of the stroke curve of ideal blank holder force,loading mode,the variation of blank holder force with stroke or regions,as well as control modes and methods.For BHFT,a classification method was proposed based on force transmission medium,loading and energy consumption methods,and the magnetic blank holder was classified into the blank holder method using magnetic materials as the force transmission medium.The force during blank holding process was analyzed and classified,and the energy consumption of different blank holder methods was qualitatively analyzed.It is pointed out that the work of blank holder force required to suppress sheet wrinkling during the process is small.Using the internal force loading method of electronically controlled permanent magnet blank holder can significantly reduce energy consumption and reduce the tonnage of the equipment,which is expected to open up a new way for the development of BHFT.