ME 297
Steps of Design Process
1. Define Problem 2. Generate Concepts 3. Develop a Solution 4. Construct and Test Prototype 5. Evaluate Solution 6. Present Solution
Stitch Line
A line that indicates a sewing process on a part or an assembly.
Parts List
A list of materials or parts specified for a project. Also referred to as a bill of materials or BOM.
Location Dimension
A location dimension that defines the relationship of features of an object.
Broken-out Section
A section of an object broken away to reveal an interior feature for a sectional drawing.
Half Section
A sectional drawing based on a cutting plane line that cuts through one-quarter of an object. A half section reveals half of the interior and half of the exterior.
Full Section
A sectional drawing based on a cutting plane line that extends completely through an object.
Removed Section
A sectional view removed from the area of the cutting plane and positioned in another location.
Standard in the US
ASME
Pitch Circle
An imaginary circle passing through the points at which the teeth of the meshing gears contact each other.
Symmetry Line
Are used when partial views of symmterical parts are drawn.
Constraints
Coincident, colinear, horizontal, vertical, tanget, parallel, perpendicular, equal, mirror, midpoint
Section Line
Define where material is cut away
Outside diameter
Diameter at the top of the teeth
Ordinate Dimensioning
Dimensions taken off one corner
Parts of an Engineering Drawing
Format (TB, Border), views, dimensions, notes
Offset Section
Has a cutting plane that is bent at one or more 90 degree angles to pass through important features
Standard around the world (except US)
ISO
Dimensions
Indicate the size of the part
Title Block
Legal binding info
Leader Lines
Lines used to connect notes to related features on a drawing.
Revolved Section
Made by revolving the cross-section view 90 degrees about an axis of revolution and superimposing the section view on the orthographic view
Notes
Material, finish, tolerances
Types of Expressions
Named parameters, unnamed parameters
Dedenbum
Radial distance between the pitch circle and the bottom of the teeth
Addendum
Radial distance between the pitch circle and the top of the teeth
Views
Shows shape of the part
Baseline Dimensioning
System of dimensioning in which all dimensions are placed from a datum and not from feature to feature. Also referred to as Datum Dimensioning.
Change Block
The area of the blueprint indicating any changes or revisions made to the part views or dimensions. Change blocks should contain every revision, as well as the dates those revisions were made.
Diametral Pitch
The ratio of the number of teeth to the pitch diameter.
Center Line
These are used to show the center of holes and symmetrical features
Hidden Line
This line is used to show surfaces, edges, or corners of an object that are not in view
Cutting Plane Line
Used to designate where an imaginary cutting took place
Chain Line
Used to indicate an area or portion of a surface that is to receive special treatment.
Visible Line
Used to represent visible edges and outlines of the object being drawn.
Long Break Line
Used to shorten the view of a long part
Short Break Line
Used to shorten the view of a long part
Auxiliary Views
Used to show features that are located on an inclined surface in true size and shape.
Dimension & Extension Line
Used when dimensioning an object
Pressure angle
angle between the normal to the tooth profile at the pitch circle and tangent to the pitch circle at that point
Pitch Diameter
diameter of the pitch circle
Root diameter
distance from the bottom of one tooth to the bottom of a diametrically opposite tooth
Circular Pitch
the distance between corresponding points of adjacent teeth, measured along the pitch circle
Phantom Line
used to indicate alternative positions of moving parts, such as a door's swing
Viewing-plane line
used to indicate direction of sight when a partial view is used
