T-FLEX Parametric CAD. Fundamentals. 2D Design

Fundamentals. Two-Dimensional Design
variables or user-defined dialog with the control elements can be used for specifying the values (see the
chapter “Control Elements. Creating User Defined Dialog Boxes”).
If the fragment drawing has text fields with an external variable inserted into them (for example,
title block), then the values of such variables can be changed directly on the assembly drawing.
Let's consider first defining the fragment external variables using the list of variables. In this way, variables
may be assigned data of three types:
1) Constant (a number in the case of a real variable, or a string in the case of a text variable);
2) An assembly variable;
3) None (the variable entry left blank).
Type 1: Assigning constant value
Let’s set a particular value of the ball bearing diameter, for
example, “30”.
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In this case, as the shaft diameter varies, the inner diameter
of the ball bearing will not change. To modify the value of
the ball bearing external variable, you will have to edit the
fragment.
Fragment external variables can be pre-defined with default values when offered for defining. The
default values are copied from the respective variables in the original fragment drawing file, if the
flag “Substitute Variable values” is set in the command “SO: Set System Options” on the tab
“Fragments”.
Type 2: Assigning assembly variable
Instead of a fixed value of the ball bearing external
variable, let's type in the name “Diameter” of an existing
assembly variable. If a user puts in the name of a nonexisting
variable, the system will prompt a user to create a
new variable.
Suppose, at the insertion time, the variable “Diameter”
equals “20”. Let's modify the variable “Diameter” to
“40”. In this case, the ball bearing image will adjust
automatically.
An assembly variable can be selected from the list of
existing variables by pressing the key (see the
chapter “Main Concepts of System Operation”, the topic
“Context menu for dialog input boxes”).
If a fragment external variable was named after an assembly variable, and such assembly variable
actually exists in the current assembly drawing, the latter value will be automatically assigned to
the fragment variable (see the chapter “Variables”).
Type 3: Undefined value
You can skip defining the external variable altogether,
leaving the entry blank.