Assembly Design > Assembly Design > Using Assembly > Placing Components > Packaged Components > About Packaged or Partially Constrained Components and Mechanisms
About Packaged or Partially Constrained Components and Mechanisms
Packaged components are not fully constrained in an assembly. There are two reasons for leaving a component packaged or partially constrained in an assembly:
When you add a component to an assembly, you may not know where it fits best, or you might not want to locate it relative to the geometry of other components. Use packaging as a temporary means of placing the component. To package a component, close the Component Placement tab before the component is fully constrained, or clear the Allow Assumptions check box.
When you add a mechanism component to the assembly, a user-defined constraint set, or a predefined constraint set (connection) determines the degrees of freedom the component has in the assembly.
Adding packaged components in an assembly
Use Assemble > Package to place components in an assembly without constraining them relative to neighboring parts. Components placed in this manner are nonparametric.
When adding a packaged component, you can create placement references to fully constrained components or to packaged components. This defines an assembly design before all placements constraints are known for all parent components. When you place a component by referencing a packaged parent it is called a Child of Packaged component. A unique Child of Packaged icon , similar to the Packaged Component icon , is used in the Model Tree to indicate a component that is placed with references to a packaged parent. The component is shown as Child of Packaged in the Model Tree Status column. The icon is used only for first-level children of a packaged component.
Packaged components follow the behavior dictated by the package_constraints configuration file option.
As a design grows, the placement of children of packaged components may not remain as you intended because of the extra degrees of freedom. You can use the Fix constraint to fix, or fully constrain, a packaged component in its current location, in relation to its parent assembly.
Place a subassembly independently if you want a more immediate coordinate system, closer to the active packaged components.
You can reposition a packaged component using the Assembly > Package > Move command or the Drag dialog box.
You can change the placement of a component, regardless of how it was assembled, without having to redefine it.
When you add a component as a packaged component, the Move dialog box opens. Choose a Move option and move the pointer to position the packaged component, then click to drop the part at the required position. When a component is positioned in this manner, positioning is absolute, not relative to other components.
Mechanism assemblies
You can assemble a component using a user-defined or predefined constraint set (connection) to retain degrees of freedom for component movement in the assembly. These components are packaged and are marked as packaged in the Model Tree. Connections define a specific type of movement in the assembly. Use the Drag dialog box to move the component and check for interference with other components in the assembly. Components placed using predefined constraint sets that reference more than one packaged components are themselves packaged components. They have degrees of freedom that allow them to move independently of any one component.