SYMMETRY
This function allows the user to define a symmetrical die by mirroring the available half or quarter about a symmetry plane.
The DIE needs to be defined in the database
in order to define the symmetry plane. If there is no part defined for the die,
a DYNAFORM QUESTION window will appear as shown in Figure
Figure
Select YES, and the current part will be
assigned to the die and the function will continue. Selecting NO will
exit the function. See Figure
Figure
eta/DYNAFORM supports the following four types of part geometry.
NO
SYMMETRY (Default)
This is the
default option . If the function is toggled ON, other
functions in Figure
SYMMETRY
The part is defined as symmetrical.
HALF
SYMMETRY INPUT
Only one half of the part geometry is available. The program will mirror the half part about the symmetry plane to form the complete part.
QUARTER
SMMETRY INPUT
Only one quarter of the part geometry is available. The program will mirror the quarter part about both symmetry planes to form the complete part.
There are three types of symmetry that can be defined by the SELECT POINTS button.
X-Z PLANE
The symmetry plane is parallel to the XZ plane of the Global System. The user
must select two points. The first point defines the location of the symmetry
plane, and the second point defines the direction of the symmetry axis.
Y-Z PLANE
The symmetry plane is parallel to the YZ plane of the Global System. The user must select two points. The first point defines the location of the symmetry plane, and the second point defines the direction of the symmetry axis.
TWO-XY-POINT
The symmetry plane is normal to the XY plane of the Global System and through the selected two points. The user must select two points. The first point defines the location of the symmetry plane, and the second point determines the direction of the symmetry axis.
If the nodes at the plane of symmetry are not perfectly collinear along the symmetry plane, use ALIGN NODES function to correct the problem. When the part is defined as Half Symmetry or Quarter Symmetry, DYNAFORM will activate the ALIGN NODES function. The user can define the tolerance in the dialog window to align the nodes along the line of symmetry. The program will show the result of the align nodes operation and prompt the user for acceptance.
If QUARTER SYMMETRY INPUT is selected, there are two symmetry planes and two symmetry axes. One symmetry axis is vertical to the first and through the base point (first selected point). The other symmetry axis is vertical to the first plane and through the second symmetry axis.
If HALF SYMMETRY INPUT or QUARTER SYMMETRY is toggled ON, the MIRROR GEOMETRY button will be activated. This function allows the user to select elements to mirror about the symmetry plane(s). The UNDO button is used to undo the mirror operation.
Follow the below steps to design the symmetrical die.
1. Read in the symmetrical geometry, mesh it and assign it to DIE.
2. Select a geometry type, for example, HALF SYMMETRY.
3. Select a symmetry type, for example, X-Z PLANE.
4. Using the SELECT POINT button, select two points to define the symmetry plane and the axis direction.
Figure
5. Click MIRROR GEOMETRY SYMMETRY, then
select the part as shown in Figure
Figure
Note: Once the symmetry axis is defined, the
created binder will be symmetrical and consist of two surfaces as shown in
Figure
Figure