Patent ID: 9505593
Filing Date: 2016-11-29
CPC Classification: B66F,F15B

Claim Text:
1. A jacking device, including: a base member, including a base surface adapted to engage a substrate surface, having a base screw thread; an upper member, including an upper surface adapted to engage a load to be raised or lowered, having an upper screw thread; at least one intermediate member, positioned between said base member and said upper member, each intermediate member including first and second screw threads adapted to engage a respective screw thread of an adjacent member; drive means, adapted to permit relative movement of each of said members to thereby raise or lower said upper surface, said drive means including: a primary hydraulic drive cylinder positioned between said base surface and said upper surface to substantially raise/lower said upper surface relative to said base surface; and, a backup drive motor to rotate each intermediate member; a linear bearing, to substantially prevent rotational movement of said upper and base members whilst permitting rotation of each intermediate member as said drive means is operated; a controller, operable by a user to control the raising/lowering of said jacking device by simultaneously controlling operation of said hydraulic drive cylinder to effect substantially vertical movement of said upper surface relative to said lower surface, whilst controlling cooperative rotational movement of each intermediate member via said backup drive motor.