Definition:Screw (Machine)

Definition

A screw is a simple machine consisting of:

a cylindrical or conical body

a helical groove cut into its surface

Thus it can be considered as a wedge wound in the form of a helix.

When the end of the screw $S$ is placed against a substance, a rotation of $S$ about its axis causes a translation of $S$ along this axis, and into the substance.

Thread

The helical groove cut into the surface of a screw is called its thread.

Also see

• Results about screws in the context of machines can be found here.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): screw: 1.
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): screw: 1.