Work load lifting system for a vertical vacuum furnace

A vertical vacuum furnace assembly comprising:

• a vertically oriented pressure vessel having an opening at a lower end thereof;
• a bottom head assembly dimensioned for closing the opening in said pressure vessel;
• a support structure comprising first and second preassembled leg assemblies arranged on opposite sides of said pressure vessel and having support arms attached to said pressure vessel;
• and
• a control system;
• wherein each of said preassembled leg assemblies comprises:
• first and second columns;
• a floor plate connected to the bottom ends of the first and second columns for attaching said columns to a surface;
• a cross beam connecting the first and second columns in spaced relation to each other, said cross beam being positioned at a first distance above said floor plate;
• first and second guide channels affixed longitudinally to the first and second columns, respectively, between said floor plate and the cross beam such that said first and second guide channels are on facing surfaces of said first and second columns;
• a trolley movably disposed in said first and second guide channels;
• and
• a reversible mechanism supported on said cross beam, mechanically connected to said trolley for lifting or lowering said trolley, and electrically connected to said control system whereby said reversible mechanism can be operated to lift or lower said trolley;
• wherein the reversible mechanism comprises a threaded shaft rotatably attached at one end to the floor plate, a drive mechanism mounted on the cross beam and connected to the other end of said threaded shaft, and a travelling element movably mounted on said threaded shaft and connected to the trolley;
• wherein the trolley comprises a lift assembly that includes first and second side plates arranged in spaced parallel relation, a cross beam interconnecting the first and second side plates at upper ends thereof, a cross bar interconnecting the first and second side plates at lower ends thereof, and a coupling assembly connected to said lift assembly and to the travelling element on said reversible mechanism;
• and
• wherein the coupling assembly comprises first and second lifting bars attached at lower ends thereof to the cross bar of said lift assembly, a bracket, and first and second link members pivotably connected between said first and second lifting bars and said bracket.