Counter weight door

A counter weight door comprising:

• two guides each arranged to be located on a respective side of an opening on a building;
• a door which is arranged to be supported on respective side thereon by the guides, the door having a plurality of panels each connected to the next one of the panels for common movement vertically in the guides;
• a counter weight system coupled to the door for providing counter weight for the weight of the door, the counter weight system having a plurality of counter weights each associated with a respective one of the panels;
• the counter weights being arranged vertically one above the next in a row;
• an interconnecting coupling connecting each of the counter weights to the next and arranged such that a bottom surface of each of the counter weights is spaced from a top surface of the next when the weight of the door is supported by the counter weights and such that the bottom surface of each is stacked on top of the top surface the next so as to be supported by the next as the door is moved to a position so that is not required to be supported by the counter weights;
• the interconnecting coupling including a spring arrangement housed in one of the counter weights so as to allow the counter weights to be stacked one on top of the next.

A counter weight door comprising:

• two guides each arranged to be located on a respective sides of an opening on a building;
• a door which is arranged to be supported on respective side thereon by the guides, the door having a plurality of panels each connected to the next one of the panels for common movement vertically in the guides;
• a counter weight system coupled to the door for movement of the door within the guide means having a plurality of counter weights;
• an interconnecting coupling connecting the counter weights;
• and,
• a pulley system having;
• a first guide pulley mounted adjacent a first side of the door;
• a second guide pulley mounted adjacent a second side of the door;
• a first elongate member fixed at a first end of the first elongate member to the door and extending through the first pulley;
• a second elongate member fixed at a first end of the second elongate member to the door and extending through the second pulley;
• wherein the second guide pulley has two pulley elements in a fixed rotatable relationship for receiving the first and second elongate members respectively, the first and second elongate members each extending through a third pulley at the counter weight system and each having a second end thereof anchored anchored to a fixed point.