Hand tool for making circumferential cut in bore of tube - uses screw jack effect with inclined rails effecting radial motion of cutting slide

摘要

The hand tool comprises a screw jack which is inserted in the tube (1), rotation of head elements (17, 5) effecting the radia protrusion and rotation of a cutting tool, respectively. A sleeve (4) of which the external dia. equates to the bore of the tube, houses the screw (8) of which the head projects to receive a nut (17). A rectangular section slide (11) incorporates the cutter (11a) being set in a radial slideway within the walls of the sleeve, and having a rectangular section groove in each side. The grooves are inclined at 10 deg. to the sleeve axis, and are traversed by parallel ribs (12a) projecting from the inner walls (9a) of a diametric slot in the base of the screw. As the screw moves up the ribs slide through the grooves effecting the radial displacement of the slide (11).