Hydraulic Cad Drawings Of The Auxiliary System

Under the background of a CAD system for the manifold block by Xing ZhiWei, the dissertation has mainly researched the customization development technology of AutoCAD in engineering drawing generation. The software is based on the operating system of Windows 98 and developed with AutoCAD Runtime extension (ObjectARX) under Visual C++6.0.Complied with national standards, the assistance system in engineering drawing generation includes four subsystems, which are an interactive geometrical tolerances auto-inquiry and marking subsystem, an accurate surface roughness marking subsystem, an automatic engineering technology requirement generation subsystem, an automatic specification generation subsystem. It also includes an assistant module of machining allowance auto-inquiry.With the interlinking way of ObjectARX with database reached deeply by ADO technology, it is made possible that geometrical tolerances are marked automatically to comply with de-sign customs and national standards.According to the marking principles of the surface roughness, the key angle is calculated that is necessary to marking surface roughness accurately. Based on the concept of drawing block and its attributes, the surface roughness can be marked accurately in AutoCAD.By using ODBC SDK to connect CAD internal graphic library and external database, an automatic engineering technology requirement generation subsystem is developed.To improve the efficiency of marking specification, an automatic specification generation subsystem are built by object-oriented technology.In order to improve the quality of designing and guaranty the craft paper conformity, the assistant module of machining allowance auto-inquiry is developed.By means of CAD technique, database technique, ObjectARX technique and programming for Windows technique ect, a assistance system in engineering drawing generation has been developed. It has a friendly and convenient user interface.