英语翻译
Strippers
There are tow types of strippers:fixed or spring-operated.The primary function of either type is to strip the workpiece from a cutting or noncutting punch or die.A stripper that forces a part out of a die may also be called a knockout,an inside stripper,or an ejector .Besides its primary function,a stripper may alwo hold down or clamp,posirion ,or guide the sheet,strip ,or workpiece.
The stripper is usually the same width and length as the die block ,In simpler dies,the stripper may be fastened with the same screws and dowels that fasten the die block ,and the screwheadw will be counterbored into the stripper ,In more compex tools and with sectional die blocks,the die block screws will usually be inverted ,and the stripper fastener will be independent .
The stripper thickness must be sufficient to withstand the force required to strip the strip the stock from the punch ,plus whatever is required for the stock strip channel.Except for very heavy tools or large blank areas,thethickness required for screwhead counterbores ,in the range of 3/8” to 5/8”(9.5mm—16mm),will be sufficient.
The height of the stock strip channel should be at least 1.5 times the stock thickness .This height should be increased if the stock is to be lifted over a fixed pin stop .The Channel widthshould be the width of the stock strip,plus adequate clearance to allow for variations in the width of the strip cut.
Choice of the methods of applying springs to stripper plates depends on the required pressure,space limitations,shape of the die,nature of the work ,and production requirements .Figure 9-12 presents a number of such methods.