Air chamber type patient mover air pallet with multiple control features

A flexible air pallet for frictionless movement of a flexible load supported thereon relative to an underlying generally planar fixed support surface, said air pallet including:

• a first thin flexible sheet forming a flexible, generally planar backing surface underlying the load,
• a second thin, flexible sheet underlying the flexible backing surface and directly overlying the planar support surface,
• said second thin, flexible sheet having a portion facing the generally planar fixed support surface perforated over a surface area generally conforming to the footprint of the load and defining with the flexible backing surface, at least one plenum chamber,
• said perforations opening unrestrictedly directly to the plenum chamber,
• air dispersion means operatively associated with said at least one plenum chamber to insure air flow throughout said at least one plenum chamber when the air pallet is under load,
• means for controlling pillowing of the thin, flexible sheet portion of said at least one plenum chamber to jack the flexible backing surface and the load sufficiently to permit the air pallet to accommodate surface irregularities for both the load support surface and the flexible backing surface without ballooning, and
• air inlet means for supplying compressed air to said at least one plenum chamber,
• the improvements wherein said air pallet includes within said at least one plenum chamber, at least one flexible common member joined at spaced positions respectively to said first and second flexible sheets within the perforated area underlying the footprint of the load and being of limited length, whereby said air inlet means in supplying air under pressure to said at least one plenum chamber causes said at least one common member to become taut and rigid and to thereby render said flexible, generally planar backing surface at least semi rigid to at least support said load and to produce an air film upon jacking of the flexible backing surface and the load above said fixed support surface by escape of compressed air from said at least one plenum chamber through said perforations, and said at least one flexible common member defining lateral anti shrink means for restricting the reduction in air pallet size in a plane parallel to the air film during air pressurization of said at least one plenum chamber.

A flexible air chamber-type air pallet for frictionless movement of a load support thereon relative to an underlying generally planar fixed support surface, said air pallet being formed of thin, flexible sheet material consisting of a first thin, flexible sheet at least partially defining a flexible, generally planar backing surface for supporting said load thereon, and

• a second thin, flexible sheet directly underlying and sealed to said backing surface and directly overlying said fixed load support surface and being sealed thereto along longitudinal lines at laterally spaced positions to form a series of laterally connected plenum chambers, said second thin, flexible sheet having a plurality of perforations therein facing said fixed support surface within said linked plenum chambers, said perforations opening directly into and out of said plenum chambers,
• air dispersion means for said plenum chambers to insure air flow through said chambers when said air pallet is under load,
• air inlet means to said chambers for directing compressed air into said plenum chambers for jacking said load and for discharge of said air from the plenum chambers through said perforations to create an air film between said thin, flexible bottom sheet and said fixed support surface,
• pillowing means to cause, upon air pressurization of said chambers said thin, flexible sheet portions of said chambers to jack the backing surface and said load sufficiently to permit the pallet to accommodate surface irregularities and to move said load on said air film,
• means for rendering said plenum chambers sufficiently rigid under said load to support said load when said chambers are pressurized, and
• means for limiting the amount of lateral shrink across the air pallet upon air pressurization of said plenum chambers so that said air pallet plenum chambers can lift said load.

A flexible film air chamber-type air pallet for frictionless movement of a load supported thereon relative to an underlying generally planar fixed support surface, said air pallet comprising:

• a flexible, generally planar backing surface for supporting said load thereon,
• a thin, flexible sheet directly underlying said flexible backing surface and directly overlying said load support surface,
• a portion of said thin, flexible sheet facing said generally planar fixed support surface being perforated and being sealed to and defining with said backing surface at least one plenum chamber, said perforations extending over an area generally corresponding to the footprint of the load with said perforations opening directly into said at least one plenum chamber,
• air dispersion means for said plenum chamber to insure air flow through said chamber when said chamber is under load and being pressurized,
• air inlet means opening to said at least one plenum chamber for permitting air under pressure to enter into the plenum chamber for jacking said load, for discharge of the air from said plenum chamber through said perforations to create an air film between the flexible, thin sheet and said fixed support surface over the area of the perforations,
• pillowing means for jacking the backing surface and said load sufficiently to permit the pallet to accommodate surface irregularities and move said load on a film of air without said thin, flexible bottom sheet ballooning, means for preventing said at least one plenum chamber from hot dogging for preventing load instability and for maintaining said at least one plenum chamber planar in a direction parallel to the developed air film for retention of the load on said backing surface during movement of said load via said air pallet on said developed air film, and
• means for limiting shrink of the air pallet laterally parallel to the plane of the developed air film over the surface area of the perforations to insure that the footprint of the air film generally matches that of the load.

In a flexible air chamber-type air pallet for frictionless movement of a load supported thereon relative to an underlying generally planar fixed support surface, said air pallet being formed of thin, flexible sheet material comprising a first thin, flexible sheet at least partially defining a flexible, generally planar backing surface for supporting said load thereon, and

• a second thin, flexible sheet underlying said backing surface and directly overlying said fixed load support surface and being connected thereto along longitudinal lines at laterally spaced positions to form a series of laterally connected, linked plenum chambers, said second thin, flexible sheet having a plurality of perforations therein facing said fixed support surface within said linked plenum chambers, said perforations opening directly into and out of said plenum chambers,
• air dispersion means for said plenum chambers to insure air flow through said chambers when said air pallet is under load,
• air inlet means to said chambers for directing compressed air into said plenum chambers for jacking said load and for discharge of said air from the plenum chambers through said perforations to create an air film between said thin, flexible bottom sheet and said fixed support surface,
• pillowing means to cause, upon air pressurization of said chambers said thin, flexible sheet portions of said chambers to jack the backing surface and said load sufficiently to permit the pallet to accommodate surface irregularities and to move said load on said air film, the improvement comprising:
• means for controlling the amount of lateral shrink across the pallet upon air pressurization of said plenum chambers so that said air pallet plenum chambers can lift said load, and
• means for rendering said first thin flexible sheet over the area of said perforations sufficiently rigid to support said load when the chambers are pressurized and means to prevent load instability and hot dogging of said air pallet under load.

A flexible film air chamber-type air pallet for frictionless movement of a load supported thereon relative to an underlying generally planar fixed support surface, said air pallet comprising:

• a flexible, generally planar backing surface for supporting said load thereon,
• a thin, flexible sheet underlying said flexible backing surface and directly overlying said load support surface,
• a portion of said thin, flexible sheet facing said generally planar fixed support surface being perforated and being sealed to and defining with said backing surface at least one plenum chamber, said perforations extending over a surface area of said thin, flexible sheet corresponding generally to the footprint of the load with said perforations opening directly into said at least one plenum chambers,
• air dispersion means for said plenum chamber to insure air flow through said chamber when said chamber is under load and being pressurized,
• air inlet means opening to said at least one plenum chamber for permitting air under pressure to enter the at least one plenum chamber for jacking said load, and for discharge of the air from said plenum chamber through said perforations to create an air film between the flexible, thin sheet and said fixed support surface over the area of the perforations,
• pillowing means for jacking the backing surface and said load sufficiently to permit the pallet to accommodate surface irregularities and move said load on a film of air without said thin, flexible bottom sheet ballooning, and
• means for preventing said at least one plenum chamber from hot dogging, for preventing load instability, for maintaining said flexible backing surface planar in a direction generally parallel to the developed air film for retention of the load on said backing surface during movement of said load via said air pallet on said developed air film and for limiting shrink of the air pallet laterally, generally parallel to the plane of the developed air film to insure that the footprint of the air film generally matches that of the load, and means for rendering said flexible generally planar backing surface sufficiently rigid under said load to support said load upon jacking when said at least one plenum chamber is air pressurized.