Screw

A screw joint is a five degree-of-freedom kinematic pair used in mechanisms. Screw joints imposes a relation between the rotation of one body (Body 1) about an axis to the translation of the other body (Body 2) along an axis. The pitch of the joint completes this relation. One full rotation of Body 1 translates Body 2 by a distance equal to the pitch. Screw joints are commonly used in applications such as bolt and nut constraints and rack and pinion steering.

1. If the Joints panel is not currently displayed, select the desired joint by clicking on it in the Project Browser or in the modeling window.
   The Joints panel is automatically displayed.
2. From the Connectivity tab, click Body 1 and pick a body from the modeling window, or double-click Body 1 to open the Model Tree (from which the desired body can be selected).
   Note: If the selected joint is a pair entity, first distinguish between the Left and Right tabs in the panel, and then edit the properties. When defining a pair joint, use pair entities for Body, Origin, etc.
3. Similarly, click Body 2 and select the desired body from the modeling window (or use the Model Tree).
4. Click the Point collector (under Origin) and select a point from the modeling window, or double click the Point collector to open the Model Tree (from which the desired point can be selected).
5. Specify the alignment axis for the joint.
   • Point - Select a point that lies on the desired alignment axis for the joint.
   • Vector - If the alignment axis for the joint is along any of the global axes, then the global x, y,or z axis can be selected by clicking on the desired axis in the modeling window or by browsing through the Model Tree.
6. Click the Properties tab and enter a value for Pitch.