Longitudinally stiffened flexible lifter for arcuate objects

Claim 2

A vacuum lifter for arcuately shaped objects comprising a flexible sheet which is formed of a flexible material and has opposed parallel surfaces and a source of vacuum, said sheet having a port through which said vacuum source communicates, a supporting member connected to one surface of said sheet, a resilient sealing gasket connected to the opposing surface of said sheet about the periphery thereof, and stiffening means connected to said flexible sheet to prevent bending of said sheet about a line extending at an angle transverse to the longitudinal extent of said sheet, said stiffening means comprising a plurality of closely spaced longitudinally extending plates provided along the entire transverse extent of said flexible sheet, said lifter being secured to an arcuate object by placing said gasket against the outer surface of said object so that a partial vacuum is formed in the compartment formed between the outer surface of said object, said sheet and said gasket, said sheet accommodating a range of diameters of arcuate objects by bending around its longitudinal axis to conform to the diameter of said object.

Claim 3

The vacuum lifter of claim 1 wherein said closely spaced longitudinally extending plates are connected to the front and rear surfaces of the flexible sheet.

Claim 4

The vacuum lifter of claim 2 wherein the longitudinally extending plates connected to the side of said sheet that said gasket is connected each have spacing means connected between the plates and said sheet, said spacing means enabling a uniform distribution of the partial vacuum in the compartment formed between an object to be lifted, the gasket and said flexible sheet.

Claim 5

The vacuum lifter of claim 1 wherein said gasket includes an enlarged portion on one side of said lifter, said enlarged portion being provided on the uppermost edge of said lifter when said lifter engages an object to be lifted, said enlarged portion being integral with said gasket and movable with respect to said sheet so that said portion provides a fortified sealing area when said object is lifted.

Claim 6

A vacuum lifter for arcuately shaped objects comprising a flexible sheet having opposed parallel surfaces and a source of vacuum, said sheet having a port through which said vacuum source communicates, a supporting member connected to one surface of said sheet, a resilient sealing gasket connected to the opposing surface of said sheet about the periphery thereof, and stiffening means connected to said flexible sheet to prevent bending of said sheet about a line extending at an angle transverse to the longitudinal extent of said sheet, said lifter being secured to an arcuate object by placing said gasket against the outer surface of said object so that a partial vacuum is formed in the compartment formed between the outer surface of said object, said sheet and said gasket, said sheet accommodating a range of diameters of arcuate objects by bending around its longitudinal axis to conform to the diameter of said object, said supporting member including an arcuate plate which is connected centrally to said flexible sheet, said arcuate plate including means for urging the transverse ends of said lifter in an arcuate shape to facilitate seating of the gasket against an arcuate object.

Claim 7

A vacuum lifter for arcuately shaped objects comprising a flexible sheet having opposed parallel surfaces and a source of vacuum, said sheet having a port through which said vacuum source communicates, a supporting member connected to one surface of said sheet, a resilient sealing gasket connected to the opposing surface of said sheet about the periphery thereof, and stiffening means connected to said flexible sheet to prevent bending of said sheet about a line extending at an angle transverse to the longitudinal extent of said sheet, said lifter being secured to an arcuate object by placing said gasket against the outer surface of said object so that a partial vacuum is formed in the compartment formed between the outer surface of said object, said sheet and said gasket, said sheet accommodating a range of diameters of arcuate objects by bending around its longitudinal axis to conform to the diameter of said object, said supporting member including an arcuate plate which is connected centrally to said flexible sheet, said arcuate plate including means for urging the transverse ends of said lifter in an arcuate shape to facilitate seating of the gasket against an arcuate object.

Claim 8

The vacuum lifter of claim 5 wherein said means for urging includes a pair of leaf springs which extend through said arcuate plate and urge the outermost edges of said flexible sheet inwardly, said springs enabling said transverse ends of said lifter to be resiliently flexible when said edges engage an object to be lifted.

Claim 9

The vacuum lifter of claim 1 and further including limiting means provided on at least one oF said transverse edges of said lifter, said limiting means acting to prevent more than a predetermined spacing between said flexible lifter and said support means.