T-FLEX Parametric CAD. Fundamentals. 2D Design

Fundamentals. Two-Dimensional Design
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5. Use of special functions of variables. In some cases when inserting the fragment in absolute
coordinates, the functions of the T-FLEX CAD variables can be used. For example, it is used for making
the title block. In the parametric drawing of the title block the special functions that read the coordinates
of the page borders of the assembly drawing are utilized. Then the coordinates are passed via the
variables to the corresponding construction lines. Thus, the title block automatically takes the desired
size in accordance with the specified page size of the assembly drawing.
Use of Fragment Variables
When inserting a fragment, one can define the values of the variables that define the fragment drawing. For
this, the desired variables must be marked as external when creating the drawing of the future fragment. For
example, to be able to define a circle radius of a fragment when inserting it in other drawings, assign an
external variable (say, “R”) to the circle radius when creating the respective construction circle. After that,
any time when inserting this fragment into other drawings, the system will ask for the value of the variable
“R”, and then adjust the fragment image according to the input value.
The external fragment variables play an important role by
relating the fragment parameters with those of the
assembly drawing. For example, consider a drawing
representing a shaft, whose diameter is assigned the
variable “Diameter”.
Suppose, we need to mount a ball bearing on the shaft. A
variable “d” was created in the ball bearing drawing that
is responsible for the value of the ball bearing inner
diameter. The variable “d” is marked as external. All the
rest of the ball bearing parameters are interrelated in such
a way that they are driven by the value “d”.
Now, as the bearing is inserted in the shaft drawing, the
two variables can be related.
After the above steps, modifications to the shaft diameter,
that is, to the variable “Diameter” of the assembly
drawing, will be automatically propagate as changes to the
variable “d” in the fragment, leading to the desired
adjustment of its image.
An assembly variable name can be set the same as an external variable name of the fragment. When inserting
a fragment in the current assembly drawing, if a same-name variable is found in the fragment as an assembly
variable, the latter will be automatically assigned the respective external fragment variable.