Screw jack, to support a plate structure with height adjustment, has an inner tubular/cylindrical body with spaced grooves around it within a tubular carrier covered by an outer sleeve, with balls in the carrier openings

摘要

The screw jack, to adjust the height of support structures, has at least one tubular or cylindrical body (1) with one or more spaced grooves (2) around it. The upper end of the body is attached to the supported structure in a durable or release mounting. The body has a sliding movement within a tubular carrier (3), which has a number of openings (4) at right angles to the symmetrical axis on at least one plane. At least one ring-shaped sleeve (5) slides on the outer carrier, with at least one inner surface (10) at an angle to the axial line, to form a wedge with the outer surface of the carrier. Or the inner sleeve surface has radial wedge surfaces matching the openings. Balls (6) and/or rollers are in the openings between the groove(s) at the inner body and the inner wall surface of the outer sleeve.