Convertible lift mechanism having a number of retractable stairs with a lift platform positioned thereunder

A method of operating a convertible lift mechanism for moving an object from a lower surface to a vertically displaced upper surface, with (i) said lower surface and said upper surface having a vertical wall interposed therebetween, and (ii) said convertible lift mechanism having (a) a lift platform, (b) a gate member pivotally coupled to said lift platform, and (c) a number of retractable stairs, said method comprising the steps of:

• positioning said lift platform in a lowered platform position in which said lift platform is positioned approximately level with the lower surface;
• positioning said gate member in an extended gate position in which said gate member is orientated substantially parallel to said lift platform so as to form a bridging surface between said lower surface and said lift platform;
• positioning each of said number of retractable stairs in an extended stair position in which a stepping surface associated with each of said number of retractable stairs extends out of an opening defined in said vertical wall;
• retracting said stepping surface of each of said number of retractable stairs into said opening defined in said vertical wall so as to position each of said number of retractable stairs into a retracted stair position;
• positioning said gate member in a retracted gate position in which said gate member is orientated substantially perpendicular to said lift platform so as to form a retaining surface for retaining said object on said lift platform;
• and
• moving said lift platform from said lowered platform position to a raised platform position in which said lift platform is positioned approximately level with said upper surface.

A convertible lift mechanism for moving an object from a lower surface to a vertically displaced upper surface, said lower surface and said upper surface having a vertical wall interposed therebetween, said convertible lift mechanism comprising:

• a number of retractable stairs, wherein (i) each of said number of retractable stairs includes a substantially horizontal stepping surface, and (ii) each of said number of retractable stairs is horizontally movable between (a) a retracted stair position in which said stepping surface is received into an opening defined in said vertical wall, and (b) an extended stair position in which said stepping surface extends out of said opening defined in said vertical wall;
• a lift platform which is movable between (i) a lowered platform position in which said lift platform is positioned approximately level with the lower surface, and (ii) a raised platform position in which said lift platform is positioned approximately level with said upper surface;
• and
• a number of vertical screw drive mechanisms, wherein (i) each of said number of vertical screw drive mechanisms includes a driven lift nut, (ii) each of said driven lift nuts of said number of vertical screw drive mechanisms is secured to said lift platform, and (iii) actuation of said number of vertical screw drive mechanisms causes movement of said driven lift nuts thereby moving said lift platform between said lowered platform position and said raised platform position.

A convertible lift mechanism for moving an object from a lower surface to a vertically displaced upper surface, said lower surface and said upper surface having a vertical wall interposed therebetween, said convertible lift mechanism comprising:

• a lift platform which is movable between (i) a lowered platform position in which said lift platform is positioned approximately level with the lower surface, and (ii) a raised platform position in which said lift platform is positioned approximately level with said upper surface;
• a first retractable stair having a first substantially horizontal stepping surface, said first retractable stair being horizontally movable between (i) a first retracted stair position in which said first stepping surface is received into an opening defined in said vertical wall, and (ii) a first extended stair position in which said first stepping surface extends out of said opening defined in said vertical wall;
• a second retractable stair having a second substantially horizontal stepping surface, said second retractable stair being horizontally movable between (i) a second retracted stair position in which said second stepping surface is received into said opening defined in said vertical wall, and (ii) a second extended stair position in which said second stepping surface extends out of said opening defined in said vertical wall;
• and
• a contact member secured to said first retractable stair, wherein (i) said contact member contacts said second retractable stair during movement of said first retractable stair from said first retracted stair position to said first extended stair position so as to urge said second retractable stair into said second extended stair position, and (ii) said contact member contacts said second retractable stair during movement of said first retractable stair from said first extended stair position to said first retracted stair position so as to urge said second retractable stair into said second retracted stair position.