Safety windshield

Claim 2

In a safety windshield, a pane comprising superposed outer and inner sheets of silicate glass, at least said outer sheet being untempered, said sheets being unitized by an interlayer of adhesive plastic, and a mounting frame gripping the periphery of said outer sheet, said inner sheet having dimensions such that at least its top and bottom border edges stop short of and are free and clear of said mounting frame by a pre-selected distance.

Claim 3

The windshield of claim 1, said interlayer and inner sheet being essentially conterminous to thereby afford a narrow free peripheral area of said first sheet of rigidity materially less than that of the area defined by the boundary of said inner sheet and said interlayer.

Claim 4

The windshield of claim 1, said inner sheet having its peripheral edge contiguous to but out of contact with the inner edge of the frame, the peripheral edge of the plastic interlayer being radially inset from the peripheral edge of said inner sheet.

Claim 5

The windshield of claim 1, the peripheral edge of said outer sheet being fixed in the frame substantially throughout its periphery, said inner sheet having peripherally-spaced discrete radial extensions each extending into and held by said frame, the interlayer being conterminious with said inner sheet and its extensions.

Claim 6

The windshield of claim 1, said inner sheet also being untempered.

Claim 7

The windshield of claim 1, the border edges of said inner sheet stopping short of and being free and clear of said mounting frame, throughout the peripheral extent thereof.

Claim 8

The windshield of claim 6, the spacing of the border edge of said inner sheet from said frame being a preselected essentially uniform distance of between about 1 and 8 mm., and preferably between about 1 and 5 mm.

Claim 9

A windshield comprising a pane of untempered silica glass and a mounting frame therefor, said pane comprising a first exterior sheet, the peripheral border of which is gripped in and by the frame, and a second interior sheet of glass adhesively secured to said first sheet in superposed relation therewith, saiD second sheet being supported essentially solely by said first sheet and having its boundary edge spaced from said frame by an essentially uniform pre-selected distance of from about 1 to 8 mm.

Claim 10

A windshield comprising a pane of untempered silica glass and a mounting frame therefor, said pane comprising a first exterior sheet, the peripheral border of which is gripped in and by the frame, and a second interior sheet of glass adhesively secured to said first sheet in superposed relation therewith, saiD second sheet being supported essentially solely by said first sheet and having its boundary edge spaced from said frame by an essentially uniform pre-selected distance of from about 1 to 8 mm.

Claim 11

The windshield of claim 8, the spacing between the frame and the boundary edge of said sheet being between about 1 and 5 mm.

Claim 12

The windshield of claim 8, said second sheet including integral relatively narrow projections spaced about its periphery, each said projection extending into and being gripped by said frame.

Claim 13

A windshield for vehicle comprising an exterior sheet of untempered silicate glass having a peripheral marginal portion thereof gripped by a supporting frame, an interior sheet of glass, and an interlayer of plastic material interposed between the interior sheet and the interior surface of the exterior sheet to thereby support the interior sheet, the major portion of the peripheral edge of the interior sheet being within the inner periphery of said gripped marginal portion of the exterior sheet and the major portion of the peripheral edge of said interlayer being spaced inwardly from said gripped marginal portion of the exterior sheet a uniform distance of between 1 mm. and 8 mm., said distance being inversely related to the level of impact energy required to be applied to the inner surface of the windshield to cause fracture of the exterior sheet along the space between the gripped marginal portion thereof and said interlayer.

Claim 14

A windshield for vehicle comprising an exterior sheet of untempered silicate glass having a peripheral marginal portion thereof gripped by a supporting frame, an interior sheet of glass, and an interlayer of plastic material interposed between the interior sheet and the interior surface of the exterior sheet to thereby support the interior sheet, the major portion of the peripheral edge of the interior sheet being within the inner periphery of said gripped marginal portion of the exterior sheet and the major portion of the peripheral edge of said interlayer being spaced inwardly from said gripped marginal portion of the exterior sheet a uniform distance of between 1 mm. and 8 mm., said distance being inversely related to the level of impact energy required to be applied to the inner surface of the windshield to cause fracture of the exterior sheet along the space between the gripped marginal portion thereof and said interlayer.

Claim 15

A windshield as defined in claim 11 wherein the interlayer and the interior sheet are coextensive.

Claim 16

A windshield as defined in claim 11 wherein the entire periphery of said interlayer is spaced from said gripped marginal portion of the exterior sheet.

Claim 17

A windshield as defined in claim 11 wherein the entire periphery of said interior sheet is within said marginal portion of the exterior sheet.

Claim 18

A windshield as defined in claim 11 wherein a portion of the frame freely overlaps a small marginal portion of the inner surface of the interior sheet.

Claim 19

A windshield as defined in claim 11 wherein circumferentially spaced portions of said interior sheet extend into and are gripped by said frame.

Claim 20

A windshield as defined in claim 16 wherein said interlayer is coextensive with said interior sheet.

Claim 23

The method of claim 18, the radial distance being selected inversely with increase in the desired minimum shattering force of impact.

Claim 24

The method of claim 19, the selected radial distance being essentially the same for windshields having the same thickness of sheets, interlayer, and emplaced angle of inclination of windshield mounting to the vertical, over a range of sizes and shapes of the glass sheets.

Claim 25

The method of claim 20, the second sheet also being of untempered silica glass.