Lecture Autodesk inventor: Multiview projections 1 - Glass box theory. After completing this chapter, you will be able to: Explain orthographic and multiview projection; identify frontal, horizontal, and profile planes; identify the six principal views and the three space dimensions; apply standard line practices to multiview drawings and sketches;...
Multiview Projections 1 Glass Box Theory Some Characteristics Parallel projectors Projectors normal to projection plane Object positioned with one face parallel to projection plane PP Projectors PEB Only one face visible need more than one view to describe object Glass Box Theory 1 Mutually perpendicular projection planes (sides of glass box) Position object inside glass box. PEB orthogonal to sides of glass box Six principal views (front/back, top/bottom, left/right) Frontal (F), Horizontal (H), Profile (P) projection planes Object dimensions (width, height, depth) Hinges – fold lines (H/F, F/P) Glass Box Theory 2 Images projected onto the projection planes Glass Box Theory 3 Sides of glass box hinged (H/F, F/P) so that when opened … Glass Box Theory 4 the views are aligned as shown here: Glass Box Theory 5 View Alignment/View Placement Arrangement of Views Top and Front are vertically aligned, share width dimension Front and Right are horizontally in line, share height dimension Top and right are not aligned, share depth dimension Transfer of Depth Every point or feature in one view must be aligned on a parallel projector in an adjacent / related view Line Conventions Alphabet of lines Visible lines – used to represent visible edges on an part Center Lines – used to identify centers of circles and axes of cylinders (holes). Also used to identify symmetry and to show path of motion Multiview Drawing of a Cylinder Centerlines only cross in circular view Extend center lines about 5mm past object edge edge NOTE: Limiting elements refer to the extents of a curved surface. In engineering graphics lines are use to represent limiting elements, just as they are used to represent edges limiting element Hidden Lines Hidden lines are used to show hidden features (e.g., edges, limiting elements, etc.) on an object Holes – locate limiting elements Surfaces – locate edge view of a surface Change of planes – locate position of a change of plane or a corner Multiview Projections 1 This is the end! ... Hinges – fold lines (H/F, F/P) Glass Box Theory 2 Images projected onto the projection planes Glass Box Theory 3 Sides of glass box hinged (H/F, F/P) so that when opened … Glass Box Theory 4 the views are aligned ... to describe object Glass Box Theory 1 Mutually perpendicular projection planes (sides of glass box) Position object inside glass box. PEB orthogonal to sides of glass box Six principal views (front/back, ... hinged (H/F, F/P) so that when opened … Glass Box Theory 4 the views are aligned as shown here: Glass Box Theory 5 View Alignment/View Placement Arrangement of Views Top and Front are vertically aligned,