主权项 |
1. A tilt-up door system for a building having an opening comprising:
a door frame comprising first and second vertically juxtaposed members each defining a vertical track having an upper portion and a lower portion; first and second generally horizontal members each having first and second ends, the first and second generally horizontal members extending generally laterally from respective ones of the first and second vertically juxtaposed members at the upper portion thereof with the first end adjacent the vertical track, each of the first and second generally horizontal members having a first cam surface extending from adjacent the first end toward the second end; a door having an inside and an outside sized to span the opening having a top, a bottom and two vertical sides, the two vertical sides each having a horizontally extending pivot shaft tube positioned vertically between the top and bottom of the door, and first and second cam followers extending laterally from an upper portion of the door in register with respective ones of the first cams; first and second carriages each including a horizontally extending pivot shaft journal positioned vertically between the top and bottom of the door, the first and second carriages being arranged for vertical movement along one of the vertical tracks; first and second horizontally extending pivot shafts connecting respective ones of the pivot shaft tubes to the pivot shaft journals; an actuator comprising first and second vertically extending hydraulic cylinders mounted adjacent respective ones of the first and second vertically juxtaposed members and connected to respective ones of the first and second carriages operable to move the first and second carriages along respective ones of the first and second vertical tracks; a hydraulic circuit including at least one hydraulic pump, a motor for operating the hydraulic pump and a hydraulic fluid tank; whereby, when hydraulic fluid is pumped into the first and second hydraulic cylinders the first and second carriages move vertically along the first and second vertical tracks. |