Marine lock systems and methods

A balanced marine lock system comprising:

• a lock chamber defined by:
• a pair of parallel vertical rectangular elongated walls each bounded by longitudinal horizontal top and bottom edges and opposed vertical first sides,
• first and second end walls each bounded by top and bottom edges shorter in length than said edges of said elongated walls and opposed vertical second sides of lesser height than said first sides of said elongated walls, said second sides being joined to said first sides with said longitudinal bottom edges and said shorter bottom edges all lying in a horizontal plane,
• a horizontal first bottom whose periphery joins with said elongated walls and said end walls,
• a first gate including a pair of doors each bounded by top and bottom edges and vertical third sides of height equal to the height of said first sides of said elongated walls minus said height of said second sides of said end walls, each said door being hinged at its said third side to a first side of said elongated walls above said top edge of said first end wall,
• a second gate including a pair of doors each constructed like said first gate and being hinged at its said third side to a first side of said elongated walls above said top edge of said second end wall,
• a horizontal vertically movable first floor within said lock chamber having an area conforming to, but slightly less, than the horizontal cross-sectional area of said lock chamber,
• inflatable gasket means associated with the periphery of said first floor to prevent liquid supported thereby from flowing below its level and to form a variable volume first pressure compartment between said first floor and said first bottom, and
• first hydraulic means to positively raise and lower said first floor,
• a balance chamber defined by:
• a pair of vertical side walls, a pair of vertical end walls, a horizontal second bottom whose periphery joins with said balance chamber vertical walls and end walls and a open top,
• a horizontal vertically movable second floor within said balance chamber having an area conforming to, but slightly less, than the horizontal cross-sectional area of said balance chamber, said area of said second floor being substantially equal to said area of said first floor,
• inflatable gasket means associated with the periphery of said second floor to prevent liquid supported thereby from flowing below its level and to form a variable volume second pressure compartment between said second floor and said second bottom,
• second hydraulic means to positively raise and lower said second floor, and
• conduit means connecting said first pressure compartment to said second pressure compartment for flow of pressurized air between them.