Tag - is being used for the old term EID (Entity IDentifier) and
for the new term object identifier. A Tag identifies an
object in the Unigraphics database. The objects are not
limited to geometrical objects, but can include parts,
instances, and occurrences.
Piece Part - This is the lowest level part in an assembly; it contains
geometry and features that represent the physical object,
but no components.
Occurrence - When several parts are brought together into an
assembly, the parts and their objects are not copied
into the assembly part. Rather, the parts are loaded into
memory, and part occurrences of those parts are put into
the assembly part.
Object Occurrence - For each object in the piece part, an object occurrence of
that object is made in the assembly part.
Instance - This is the term used to indicate the placement of a
component part within an assembly part. For each Instance,
a Part Occurrence is displayed in the assembly part.
Multi-level - Assemblies can be multi-leveled. For example, an
automobile can consist of the body and two instances of an
axle assembly part, which itself consists of an axle and
two instances of a wheel assembly part, which itself
consists of .... etc. In these cases, each Instance can
have more than one associated Part Occurrence.
Component Part - This is the usage of a part within an assembly, at a
particular location and orientation. A component may be a
sub-assembly consisting of other, lower-level components.
Each component in an assembly contains only a link to its
master geometry. When you modify the geometry of one
component, all other components in the session using the
same master update automatically to reflect the change.
Old (V9) style components are stored in the Database as
Type 63, Subtype 0. New (V10) style components are listed
as Type 63, Subtype 1.
Prototype - This is the master geometry to which an occurrence is
linked. In the case of a part occurrence, it is the piece
part containing that master geometry.
Reference Set - This is a named collection of geometry from a Unigraphics
part that may be used to simplify the representation of
the component part in higher level, large, complex
assemblies. Whenever the name of a reference set is passed
in to a routine, if the string is NULL or blank, the whole
part is used. If the string "Empty" is used, the empty
reference set is used.
Displayed Part - This is the part that is being viewed in the graphics
window. It can either be a piece part or an assembly.
The displayed part must be fully loaded. A partially
loaded part can be made the displayed part by opening it.
Work Part - This is the part whose geometry or assembly structure is
being modified. The Work Part can be the same as the
Displayed Part or any component of the Displayed Part if
it is an assembly. The work part may be partially loaded,
but must be a member of the assembly which is the displayed
part. Only objects of the work part may be edited.
Object occurrences can not be edited, but they may be
queried to find their data.作者: endiaons 时间: 2005-8-11 12:50
找本UG的书应该没问题吧