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 t

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 PEB

Projectors

PP

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 /

Line Conventions

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

Alphabet of lines

Multiview Drawing of a Cylinder

Centerlines only

cross in circular

view

Extend center

lines about 5mm

past object 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.

edge

limiting element

Hidden Lines

Holes – locate

limiting elements

Surfaces – locate

edge view of a

surface

Change of planes

– locate position

of a change of

plane or a corner

Hidden lines are used to show hidden features (e.g., edges, limiting elements, etc.) on an object

Multiview Projections 1

This is the end!