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本文以最大机械效率为目标函数,运用求极值方法分析和计算了各种斜楔的最佳角度,並得出了各种斜楔最佳角度的统一表达式a最佳=40°±θ╱2。其结论对带斜楔模具的设计有一定指导意义。一般冲压加工为垂直方向。当冲件加工方向必须倾斜时,则要采用带斜楔的冲模,将垂直方向的机械压力转变为倾斜方向的力。斜楔冲模按滑块运动方向与水平方向的夹角可分为水平斜楔模,正向倾斜斜楔模,反向倾斜斜楔模,如图1所示。这三种斜楔模广泛用于冲孔、切缺,切边以及冲件侧边向内弯曲,加工凸缘等冲压工序中。图中斜楔传递角a的大小将直接影响模具机械效率的高低。a角与机械效率的关系及最佳x角的确定,在设计斜楔模中是很重要的。关于水平斜楔模最佳角度计算,文献[2]中进行了讨论。本文主要讨论正向倾斜斜楔模及反向倾斜斜楔模的最佳角度。并指出三种斜楔模最佳角度之间的关系。 相似文献
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叙述了中立柱外板的零件结构及工艺分析,主要介绍了修边冲孔、斜楔冲孔模的结构及其特点,并介绍了双斜楔与滑块的运动关系。 相似文献
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针对传统填充复合斜楔结构的缺点,提出了改进方法。传统填充复合斜楔结构中,采用刚性斜楔镶板来驱动活动驱动滑块和活动凸模,并且这二者均采用氮气缸进行回程,斜楔镶板由于高频次、高速运动和做功,导致磨损严重,影响斜楔结构的精度。对传统填充复合斜楔结构进行改进;采用气缸驱动活动驱动滑块和活动凸模进行工作和回程行程,有效地解决了传统填充斜楔结构使用时,由于斜楔镶板磨损引起的零件定位不可靠的问题。另外,采用辅助氮气缸推动活动凸模进行工作行程,也解决了气缸驱动活动凸模时冲压生产节拍慢的问题。 相似文献
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单双斜楔在弯曲模中的应用 总被引:1,自引:0,他引:1
为了提高工作效率,将弯曲模设计中常见的几种单、双斜楔结构进行了分类总结,介绍了各种单、双斜楔的结构及在弯曲模中的应用、工作过程和适用条件。 相似文献
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大吨位油压机主要用于铁路货车部分零件的拉伸成形.如70吨级通用敞车下侧门板、70吨级通用棚车侧板等零件.为了进一步提升零件的产品质量和零件平面度,油压机应具有上压边功能,满足正拉伸成形所需要的压边力,从而实现对零件产品质量和平面度要求.本文通过分析起伏成形件压型模具与大吨位油压机工作结合部分原理,从优化大吨位油压机压边结构入手,实现提高零件产品质量和平面度的目的. 相似文献
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以一套后背门内板模具为例,在侧冲孔角度不理想、摆放斜楔较困难的情况下,重点介绍为解决斜楔摆放的空间问题而提出的偏心冲孔斜楔结构,此结构对冲孔角度不理想,常规斜楔结构不能满足冲压要求的情况下十分有效,同时此结构简单、易装配。 相似文献
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A various number of products exist which require a clean-sheared edge due to function or surface feel. Traditionally, these
parts are produced on fine blanking presses with three separate and distinct movements. Shaving, in particular counter-shaving
is a shearing operation to improve the edge quality of a blanked part or punched hole. This paper introduces a progressive
die tool to realize the counter-shaving process on a single acting press. Advancing the chip flow through choosing a cutter
angle can achieve up to a 85% clean-sheared edge and rectangular edge. Thereby, a sharp-edged transition—without any rollover
depth—between the upper surface of the sheet metal and the sheared-edge are formed. The end of the clean-sheared edge is followed
by a tear which shapes a burr in the form of a triangular lappet, which can be deburred in a subsequent vibratory grinding
process. Experimental results of different process parameters for two sheet metal materials at three thicknesses are discussed
and compared to finite element calculations.
The presented research work was supported by the German Research Foundation (DFG). 相似文献
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J.J. Hernndez P. Franco M. Estrems F. Faura 《Journal of Materials Processing Technology》2006,180(1-3):143-150
The main defects that characterize the quality and accuracy of blanked parts are the form errors which can be found on the blanked surface. These defects are basically related to tool wear and process parameters. This work presents theoretical modelling of the effects of tool wear on the shearing mechanism and resulting form errors. To this end, a new parameter denominated effective clearance, which characterizes the distance between a punch and the die cutting edge when a tool is worn, is defined. An experimental analysis of form errors as a function of this new parameter is made, using 6 and 8 mm AISI A2 steel punches and 1 mm thick AISI 304 stainless steel sheet. Finally, design criteria are proposed for the process parameters to fulfil the quality requirements of blanked parts. 相似文献
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