Ground effect dolly

Claim 2

A ground effect dolly adapted for moving, along a generally smooth planar and horizontal supporting surface, a tall heavy load whose base portion is relatively narrow, comprising an elongated rigid platform adapted to be disposed under said load in a horizontal position, first and second pairs of gas cushion means mounted to the underside of said platform with the straight line joining the centers of pressure of gas cushion means of said first pair intersecting the straight line joining the centers of pressure of gas cushion means of said second pair; the first pair located one at each end of the platform and adapted to produce a significantly greater lifting force than the cushions of the second pair, and the second pair located adjacent the long sides of the platform and adapted to balance the load in a direction transverse to the direction of elongation, supply means connectable with a source of pressurized gas; duct means adapted to feed a flow of pressurized gas to said gas cushion means; and pressure differential flow resistance means operable while the load is being supported by the cushions for controllably reducing the flow of pressurized gas to said second pair of gas cushion means relative to the flow to said first pair of gas cushion means until each gas cushion means of said first pair when inflated of said gas produces a significantly greater lifting force than the mean lifting force of gas cushion means of said second pair thereof and the cushions of the second pair provide stability in a direction transverse to the direction of elongation.

Claim 3

A ground effect dolly adapted for moving along a generally horizontal, smooth, planar surface a tall and heavy load supported in its static upright position by means of two spaced apart posts defining the small sides of a narrow rectangular base area on said surface, comprising: an elongated rigid platform having two opposite end portions, said platform being adapted to fit between said posts with said end portions connectable therewith for lifting said load; a pair of load bearing gas cushions mounted to said platform for primarily supporting the weight of the load, each one being located adjacent a different one of said end portions, and projecting below the bottom surface of said platform at least when gas inflated; a pair of auxiliary gas cushions mounted to said platform, one on either side of the straight line joining the centers of pressure of said load bearing gas cushions, and projecting below said bottom surface at least when gas inflated for stabilizing the load in a direction transverse to the said direction of elongation; supply means connectable with a source of pressurized gas; duct means leading from said supply means to said gas cushions; valve means for controlling the gas flow through said ground effect dolly; and differential pressure flow control means operable while the load is being supported by the cushion for controllably reducing the lifting force created by said auxiliary gas cushions relative to that created by said load bearing gas cushions until the load is primarily supported by the load bearing cushions and the pressure of the auxiliary cushions is at a level to produce stability in a direction transverse to the said direction of elongation.

Claim 4

A ground effect dolly adapted for moving along a generally horizontal, smooth, planar surface a tall and heavy load supported in its static upright position by means of two spaced apart posts defining the small sides of a narrow rectangular base area on said surface, comprising: an elongated rigid platform having two opposite end portions, said platform being adapted to fit between said posts with said end portions connectable therewith for lifting said load; a pair of load bearing gas cushions mounted to said platform for primarily supporting the weight of the load, each one being located adjacent a different one of said end portions, and projecting below the bottom surface of said platform at least when gas inflated; a pair of auxiliary gas cushions mounted to said platform, one on either side of the straight line joining the centers of pressure of said load bearing gas cushions, and projecting below said bottom surface at least when gas inflated for stabilizing the load in a direction transverse to the said direction of elongation; supply means connectable with a source of pressurized gas; duct means leading from said supply means to said gas cushions; valve means for controlling the gas flow through said ground effect dolly; and differential pressure flow control means operable while the load is being supported by the cushion for controllably reducing the lifting force created by said auxiliary gas cushions relative to that created by said load bearing gas cushions until the load is primarily supported by the load bearing cushions and the pressure of the auxiliary cushions is at a level to produce stability in a direction transverse to the said direction of elongation.

Claim 5

A ground effect dolly adapted for moving library type bookstacks along an essentially planar, horizontal, smooth surface, comprising an elongated rigid platform having two opposite end portions, adapted to closely fit between the posts of a bookstack and connectable with said posts for lifting said bookstack; a load bearing gas cushion at each one of said opposite end portions, mounted to said platform and projecting slightly therebelow at least when gas inflated for primarily supporting the weight Of the load; a pair of auxiliary gas cushions mounted to said platform and projecting slightly therebelow at least when gas inflated for stabilizing the load in a direction transverse to the said direction of elongation, said auxiliary gas cushions being disposed on either sides of the straight line joining the centers of pressure of said load bearing gas cushions; supply means connectable with a source of pressurized gas; duct means leading from said supply means to said gas cushions; valve means in circuit with said duct means for controlling the gas circuit with said duct means and for controlling the gas flow through said ground effect dolly; differential pressure flow control means in circuit with at least part of said duct means and operable while the load is being supported by the cushions for controllably restricting the flow of gas to said auxiliary gas cushions to reduce the lifting force created by said auxiliary gas cushions relative to that of said load bearing gas cushions until the load is primarily supported by the load bearing cushions and the pressure of the auxiliary cushions is at a level to provide stability in a direction transverse to the said direction of elongation; and lift adjusting means in circuit with at least part of said duct means for adjusting the difference in pressure in said load bearing gas cushions, to compensate for load imbalance in the direction of elongation of the load.

Claim 6

A ground effect dolly adapted for moving library type bookstacks along an essentially planar, horizontal, smooth surface, comprising an elongated rigid platform having two opposite end portions, adapted to closely fit between the posts of a bookstack and connectable with said posts for lifting said bookstack; a load bearing gas cushion at each one of said opposite end portions, mounted to said platform and projecting slightly therebelow at least when gas inflated for primarily supporting the weight Of the load; a pair of auxiliary gas cushions mounted to said platform and projecting slightly therebelow at least when gas inflated for stabilizing the load in a direction transverse to the said direction of elongation, said auxiliary gas cushions being disposed on either sides of the straight line joining the centers of pressure of said load bearing gas cushions; supply means connectable with a source of pressurized gas; duct means leading from said supply means to said gas cushions; valve means in circuit with said duct means for controlling the gas circuit with said duct means and for controlling the gas flow through said ground effect dolly; differential pressure flow control means in circuit with at least part of said duct means and operable while the load is being supported by the cushions for controllably restricting the flow of gas to said auxiliary gas cushions to reduce the lifting force created by said auxiliary gas cushions relative to that of said load bearing gas cushions until the load is primarily supported by the load bearing cushions and the pressure of the auxiliary cushions is at a level to provide stability in a direction transverse to the said direction of elongation; and lift adjusting means in circuit with at least part of said duct means for adjusting the difference in pressure in said load bearing gas cushions, to compensate for load imbalance in the direction of elongation of the load.

Claim 7

A ground effect dolly as defined in claim 3, wherein said duct means comprises first and second ducts leading from said supply means to said load bearing cushions respectively, and a third duct leading from said supply means to both said auxiliary gas cushions in parallel, said differential flow control means comprising a valve in circuit with said third duct.

Claim 8

A ground effect dolly as defined in claim 4, wherein said lift adjusting means comprises a pressure control valve in each said first and second ducts whereby to enable manual control of the difference in pressures in said load bearing gas cushions.

Claim 9

A ground effect dolly as defined in claim 4, wherein said straight line joining the centers of pressure of said load bearing gas cushions, and the straight line joining the centers of pressure of said auxiliary gas cushions intersect one another at right angle and at their respective middle points.

Claim 10

A ground effect dolly as defined in claim 6, wherein said platform is cruciform having a wing portion on each side of and coplanar with an elongated rectangular area, said opposite end portions defining the ends of said rectangular area, said wing portions being symmetrical with respect to the longitudinal axis of said rectangular area, and centered upon the middle point thereof, each one of said auxiliary gas cushions being at least partially located in a different one of said wing portions.

Claim 11

A ground effect dolly as defined in claim 7, wherein the width of said rectangular area is equal to the length of said wing portions, and wherein all said gas cushions are of the same dimensions.

Claim 12

A ground effect dolly as defined in claim 3, wherein each gas cushion is circular and is formed by a flexible membrane secured to the underside of said platform in a gas-tight manner by means of a rigid annular ring whose outside diameter is generally equal to the width of said rectangular area, said ring being secured to said platform, said flexible membrane having a series of small orifices disposed in a circle centered on the center of said ring, a rigid dish-shaped element having a diameter slightly less than the inside diameter of said annular ring and secured to said platform within said membrane and having spaced apart orifices, and means attaching the center of said membrane to the underside of said platform.

Claim 13

A ground effect dolly adapted for moving, along a generally smooth, planar and horizontal supporting surface, a tall, heavy load the base portion of which is relatively narrow, comprising an elongated rigid platform adapted to be disposed undeR said load in a horizontal direction, first and second pairs of gas cushion means mounted to the underside of the platform with the straight line joining the centers of pressure of gas cushion means of said first pair intersecting the straight line joining the centers of pressure of gas cushion means of said second pair; supply means connectable with a source of pressurized gas; duct means adapted to feed a flow of pressurized gas to said cushion means; said duct means comprising first and second ducts leading from said supply means to said first cushions, respectively, and a third duct leading from said supply means to both said auxiliary gas cushions in parallel; and pressure differential flow resistance means including a valve in circuit with said third duct for reducing the flow of pressurized gas to said second pair of gas cushion means whereby each gas cushion means of said first pair when inflated of said gas produces a significantly greater lifting force than the mean lifting force of gas cushion means of said second pair thereof.

Claim 14

A ground effect dolly adapted for moving, along a generally smooth, planar and horizontal supporting surface, a tall, heavy load the base portion of which is relatively narrow, comprising an elongated rigid platform adapted to be disposed undeR said load in a horizontal direction, first and second pairs of gas cushion means mounted to the underside of the platform with the straight line joining the centers of pressure of gas cushion means of said first pair intersecting the straight line joining the centers of pressure of gas cushion means of said second pair; supply means connectable with a source of pressurized gas; duct means adapted to feed a flow of pressurized gas to said cushion means; said duct means comprising first and second ducts leading from said supply means to said first cushions, respectively, and a third duct leading from said supply means to both said auxiliary gas cushions in parallel; and pressure differential flow resistance means including a valve in circuit with said third duct for reducing the flow of pressurized gas to said second pair of gas cushion means whereby each gas cushion means of said first pair when inflated of said gas produces a significantly greater lifting force than the mean lifting force of gas cushion means of said second pair thereof.