A jack in which a screw is used for lifting, or exerting pressure. See Illust. of 2d Jack, n., 5.

(connector/accessory) A mechanical fastening device (one or two per connector) used to draw mating connectors together and to separate them. Includes a threaded screw on one connector that engages a threaded bushing on the mating connector.

Synonymous with expansion screw.

screw-operated jack

A screw attached to one half of a two piece multiple contact connector used to draw and hold both halves together and to separate them.

Type of lifting device, which adjusts its height and the height of its load, by turning a threaded shaft in an internally-threaded sleeve.

A device used for the positioning of a motor. These are adjustable screws fitted on the base or motor frame.

n. a threaded rod used for centering and balancing a vault door & frame in position during installation

A jackscrew mechanism uses a long threaded rod used to position a matching nut at any position along its length. Unlike hydraulic actuators that require continual pressure to remain in a locked position, forces acting on the nut along the length of the rod do not appreciably affect the rotation of the rod so the mechanism self-locks.