The proposed system PROCOMP has been developed using production rule-based KBS approach of AI。 A brief description of design considerations, development procedure and organization of the system is given as under。
The progressive die is very complex and even an ordinary die may have several components [10-12]。 Major components of a progressive die are die block, die gages (front spacer and back gage), stripper plate, punch plate, back plate, punches, pilots, die- set and fasteners。 Critical investigation reveals that the dimensions of die block depend on various factors such as sheet thickness, direction of sharp edge, strip-width, length of strip- layout, and type of die material。 The dimensions of front spacer and back gage mainly depend on the sheet thickness。 But minimum thickness of die gages is also restricted by risk of camber which may occur during heat treatment process of its manufacturing。 The distance between back gage and front spacer depends on the width of stock strip。 The size of stripper plate corresponds to the size of die block。 The punch plate is used to position and support the punches。 The thickness of punch plate is a
function of punch diameter。 Punch plate thickness should also be proportional to the overall punch height。 The length and width of the punch plate is usually same as of die block。 Hardened back-up plates are normally interposed between small perforator punches and the punch holder。 The backup plate is generally about 10-12 mm thick。 In the selection process of die-set of progressive die, one should consider part quantity, dimensional tolerance of the component, clearance between punch and die, and clearance between guideposts and bushings。 Selection of the kind of die-set depends upon the type of sheet metal operation, part quantity and job accuracy。 The dimensions of the die-set depend upon the length and width of the die and its placement in the die-set。 In industries, the number and size of fasteners are selected on the basis of size of die block。
Development procedure of the proposed system PROCOMP includes knowledge acquisition, framing of production rules, verification of production rules, sequencing of production rules, identification of suitable hardware and computer language, construction of knowledge base, choice of search strategy, and preparation of user interface。 The system has been developed on PC (Pentium 4 CPU, 2。4 GHz, 256 MB of RAM) with Autodesk AutoCAD software [13]。 The production rules incorporated in the proposed system have been coded in AutoLISP language [14]。 The system works with input information supplied by the user coupled with knowledge stored in the knowledge base, to draw conclusions or recommendations for design of progressive die components。 The system overall comprises of more than 650 production rules。 However, the system is flexible enough as its knowledge base can be updated and modified, if necessary, on the advancement in technology。
2。3。Organization of the system
As the progressive die has several components, therefore it has been decided to organize the proposed system PROCOMP into the following modules -
1。 Module DBLOCK for selection of dimensions of die block。
2。 Module DIEGAGE for selection of dimensions of die gages (front spacer and back gage) and optimal distance between die gages。
3。 Module DIALCL for selection of proper die angle, die land and cutting clearance。
4。 Module STRPR for selection of stripper and stripper plate。
5。 Module PCHPL for selection of punch details, punch plate and back plate。
6。 Module IDSS for selection of type and dimensions of die-set。 级进模零部件的知识库系统英文文献和中文翻译(2):http://www.youerw.com/fanyi/lunwen_82603.html