Apparatus for testing glass
AssigneeLibbey-Owens-Ford Co.
InventorsRobert E. Maltby, Jr., James T. Sikorski
Life of this patent
Estimating the term…
Abstract
Apparatus for the destructive testing of glass sheets. The sheets to be tested are subjected to a differential pressure condition by establishing a vacuum on one side thereof and lowering the pressure on such side until the glass deflects to its breaking point. The vacuum system includes a control circuit which enables lowering the pressure in a controlled linear manner with time. The apparatus is designed to permit selection of and testing of sheets substantially immediately after the capping operation.
Claims7
Apparatus for the destructive testing of glass sheets, comprising a vacuum chamber defined in part by a base and side walls extending upwardly from the base, gasket means at the top of said side walls for supporting a glass sheet to be tested about the periphery thereof in fluid tight relationship with said side walls, a vacuum pump communicating with the interior of said vacuum chamber, and a control circuit for said vacuum pump, said control circuit including means for establishing a predetermined evacuation rate for said chamber and means for providing a linear decrease in chamber pressure with time.
Apparatus for the destructive testing of glass sheets, comprising a vacuum chamber defined in part by a base and side walls extending upwardly from the base, gasket means at the top of said side walls for supporting a glass sheet to be tested about the periphery thereof in fluid tight relationship with said side walls, a vacuum pump communicating with the interior of said vacuum chamber, said vacuum pump having a capacity sufficient to lower the pressure in said chamber to cause deflection of said sheet in direction of the interior of said chamber until breakage of the sheet occurs, a control circuit for said vacuum pump, said control circuit including means for establishing a predetermined evacuation rate for said chamber and means for providing a linear decrease in chamber pressure with time, and means to indicate the degree of vacuum at the moment of glass fracture.
Apparatus for the destructive testing of glass sheets, comprising a vacuum chamber section defined in part by a base and side walls extending upwardly from the base, gasket means at the top of said side walls adapted for supporting a glass sheet to be tested about the periphery thereof in fluid tight relationship with said side walls, a glass conveying section including a frame having an outline of substantially the same size and shape as the vacuum chamber section and adapted for removing said sheet to be tested from a conveyor and positioning same on said gasket means, a plurality of vacuum cups mounted within said frame for holding said sheet during conveyance thereof on said frame, means associated with said vacuum chamber section for clamping said conveying section thereto when said sheet is positioned on said gasket means, a vacuum pump communicating with the interior of said vacuum chamber, said vacuum pump having a capacity sufficient to lower the pressure in said chamber to cause deflection of said sheet in the direction of the interior of said chamber until breakage of the sheet occurs, and means to indicate the degree of vacuum in said chamber at the moment of glass fracture.
Dependencies are inferred from the claim text.