IL136939A

IL136939A - Blast-protective window construction

Info

Publication number: IL136939A
Application number: IL13693900A
Authority: IL
Original assignee: M T D Ind Ltd
Priority date: 2000-06-22
Filing date: 2000-06-22
Publication date: 2006-08-01
Also published as: WO2001098617A1; AU6629201A

Description

136,939/2 A BLAST-PROTECTIVE WINDOW CONSTRUCTION The present invention relates to a blast-protective window construction. More particularly, the invention provides improved glazing means for retaining window panels of large and varying thickness in such window.

Blast-protective or security windows are designed to withstand explosive blast forces, and/or small-arms fire, to a level usually determined by standards set by governments or local authorities. Security windows are used in buildings which may be subject to terrorist attacks, in bomb shelters, and in recent years have in Israel also come into extensive use in residential buildings provided with security rooms. Such rooms are part of the living quarters of a house or flat, and although reinforced to withstand a high degree of blast forces, and sealable against external gases, the general appearance of such rooms is reasonably similar to other rooms in the same building.

Blast protective windows are suspended from a sill frame by hinges and are designed to be openable. Hinges may be located on any side. When closed, the room is sealed against entry of gases and toxic biological contaminants, such sealing providing protection also against liquids.

Due to different blast resisting or bullet resisting requirements and standards, and also due to different window sizes, there is no one thickness of window pane which suits all windows. For example, all else being equal, a larger window requires a thicker window pane to maintain the same level of resistance as a smaller window. Furthermore, different combinations of glass/plastic sheets with different combined thickness may meet the same standard of resistance. Prior-art glazing systems, including those disclosed by the present inventor in Israel Patent no. 127,424 and other commercially-available windows, one of which is known as "DEFENDER 72", allow the use of only the design thickness. However due to the competitive nature of the market, the use of a thick window panel providing more resistance than needed to meet a specification adds unacceptable costs to the window. For these reasons it has been found that there is a need for a window frame that can be adapted to accept various thickness of window panel.

It has also been found that blast-resistant windows marketed at present have the glazing facing the inner side of the window. This is aesthetically objectionable.

US Patent nos. 3,931 ,699 5,088,255 5,806,256 and 5,924,263 among others disclose glazing systems, but no reference was found to the subject of accommodating glass of varying thickness.

It is therefore one of the objects of the present invention to obviate the disadvantages of prior art blast-resistant windows and to provide a glazing system therefor which allows the use of a window panel of various thickness, without need to change the profiles used for making the frames, as is the case today.

It is a further object of the present invention to provide an arrangement wherein improved inner appearance is achieved by locating the glazing on the outer face.

The present invention achieves the above objects by providing a blast-protective window frame construction system, comprising a) an inner window-retaining frame of extruded metal, said frame having in cross-section a first substantially L-shaped window-panel-retaining element, said L-shaped element being able to accommodate window panels of various thicknesses; wherein a flangelike base of said L-shaped element is adapted to at least indirectly support an edge of a window panel, and a back-like wall of said L-shaped element is adapted to at least indirectly support inner surfaces of said window panel, and b) an outer frame, attachable to a building and framing an opening having an inner perimeter larger than the outer perimeter of said window panel, whereby window panels of various thicknesses may project into said opening without obstruction by elements of said outer frame.

In a preferred embodiment of the present invention there is provided a blast-protective window comprising a second substantially L-shaped window-panel retaining element, provided with means for attachment of a flange-like base of the second substantially L-shaped element to the flange-like base of the first L-shaped element.

The back-like wall of the second L-shaped element is in spaced-apart substantially parallel alignment with the back-like wall of the first L-shaped element, and defining therebetween a space sized to accommodate a pre-determined thickness of the window panel, by virtue of the chosen width of the flange-like base of the second substantially L-shaped window-panel retaining element.

The back-like wall of the second L-shaped element is adapted to abut and support outer surfaces of the window panel.

In a most preferred embodiment of the present invention there is provided a blast-protective window wherein the frame is composed of at least four frame sub-units sequentially attached to each other by right-angle corner units.

Each of the frame sub-units further comprises a hollowed base sized to receive an arm of the right-angle corner units at each of its ends to form a quadrilateral frame enclosure for the window panel and wherein the hollowed area is positioned to be traversed by at least 90% of the plane of the window panel when the window panel is retained by the L-shaped elements.

Yet further embodiments of the invention will be described hereinafter.

It will thus be realized that the various embodiments of the glazing systems of the present invention serves to allow aluminium extrusions used for the inner and for the outer frames respectively to be used for large or small blast-resistant windows, for thick window panes such as those made of PVC, and for any combination of glass and plastic.

In the present specification the term "window panel" refers to a transparent plate which may be made of one or more sheets of glass, or of one or more sheets of a transparent plastic such as PVC or polycarbonate, or a combination, usually a glass-plastic-glass sandwich.

The invention will now be described in connection with certain preferred embodiments with reference to the following illustrative figures so that it may be more fully understood.

With specific reference now to the figures in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

In the drawings: FIG. 1 is a sectional view of the frames of a preferred embodiment of the blast-resistant window according to the invention; FIG. 2 is a sectional view of an embodiment having outer glass support; FIG. 3 is a sectional view of an embodiment wherein the inner and outer L-like strips interlock; FIG. 4a is a sectional view of an embodiment provided with a triple-cornered outer strip; FIG. 4b is an elevational, partly fragmented view of a framed widow showing corner joints; FIG. 5 is a sectional view of an embodiment wherein a portion of the inner frame replaces the base of a L-shaped element; FIG. 6 is a sectional view of an embodiment provided with an extension of the hollow area of the frame; and FIG. 7 is a sectional view of an embodiment adaptable for heavy-duty.

There is seen in FIG. 1 a blast-protective window frame construction system 10.

An inner window-retaining frame 12 is made of extruded aluminium. The frame as seen shown in cross-section, has a first L-shaped window-panel-retaining element 14. The flange-like base 16 of the L-shaped element 14 is adapted to support an edge 28 of the window panel 18. Fasteners 20 provide attachment to the frame 12. These are merely for retention, and are not required to resist any substantial forces as any blast force will come from the outer side. The back-like wall 22 of the L-shaped element 14 is adapted to support inner surfaces of the window panel 18.

Intermediate between the wall 22 and the window panel 18, as well as between the edge of said window panel and the flange-like base 16 is a strongly adhesive material 24 for attachment of the window panel 18 to the inner frame 12. Adhesion is preferably further improved by abrading the faces 26 adjacent to the edges 28 before assembly of the panel 18.

The L-shaped element 14 accommodates window panels 18 of varying thickness.

An outer frame 30 supports the inner frame 12 by means of hinges 32, located along one of the mutual edges of the two frames 12, 30. The outer frame 30 is attachable to a building. It frames an opening 34 having an inner perimeter larger than the outer perimeter 36 of the window panel 18. Thus window panels 18 of increased thickness may project into the opening 34 without obstruction by elements of the outer frame 30.

A seal element 37 prevents the ingress of gases when the window is in its closed position as shown in the diagram.

With regard to the rest of the figures, similar reference numerals have been used to identify similar parts.

Referring now to FIG. 2, there is seen a second embodiment of a blast-protective window 38.

A second L-shaped window-panel retaining element 40 is provided on the outer side. Means 42 such as rivets are used for attachment of a flange-like base 44 of the second L-shaped element 40 to the flange-like base 16 of the first L-shaped element 14.

The back-like wall 46 of the second L-shaped element 40 is in spaced-apart parallel alignment with the back-like wall 22 of the first L-shaped element 14, The space formed therebetween is sized to accommodate a pre-determined thickness of the window panel 48, including adhesive material 24, by virtue of the chosen width of the flange-like base 44 of the second L-shaped element 40.

The back-like wall 46 of the second L-shaped element 40 is adapted to abut and support outer surfaces of the window panel 48, including adhesive material 24. The window panel 48 in the present example is shown to be much thinner than the window panel 18 seen in FIG.1.

FIG. 3 illustrates a further embodiment of the blast-protective window 50.

The flange-like base 52 is provided with means 54, such as the upturned lip shown, for attachment thereto of a retaining strip-like element 56 in spaced-apart, parallel alignment with the back-like wall 58 of the first L-shaped element 60. The space defined therebetween is sized to accommodate a predetermined thickness of the window panel 18, including any space needed for an adhesive or sealant 24. The-strip element 56 shown is an extrusion, and is adapted to abut and support the outer surfaces of the window panel 18. Being located on the outer face, the strip 56 serves for retention and it is not stressed by the high forces caused by a blast.

Referring now to Fig. 4a, there is seen a further embodiment of the window frame 62. A triple-cornered strip 64 has an upper flange wall 66 which is adapted to abut and support outer surfaces of the window panel 18. The lower part 68 of the strip 64 is a flange-like base attached to the inner frame 62 by fasteners 42.

The strip can be made by bending sheet material or by extrusion.

Seen in FIG. 4b is a blast-protective window wherein the inner frame 2 is composed of four frame sub-units 12a-d, sequentially attached to each other by right-angle corner units 70.

Each of the frame sub-units 12a-d further comprises a hollowed base 72 sized to receive an arm of the right-angle corner units 70 at each of its ends to form a quadrilateral frame 12 enclosure for the window panel 18.

The hollowed base area 72 is positioned to be traversed by at least 90% of the plane of the window panel 18 when the window panel 18 is retained by the L-shaped elements 14 as seen in FIG.1.

Referring now to FIG. 5, there is depicted a blast-protective window 74 wherein surfaces 16 and 22 of the inner frame sub-unit 76 constitute said first L-shaped element.

Similarly to FIG. 2, a second L-shaped window-panel retaining element 40 is provided on the outer side. Fasteners 42 such as rivets are used for attachment of the flange-like base 44 of the element 40 to the inner frame 76.

The window panel is composed of two face-to-face identical sheets of toughened glass 78.

FIG. 6 shows a further embodiment of a blast-protective window 80. The window 80 is generally similar to that seen in FIG. 2. An extension 82 of the hollow area 84 of the inner frame 86 increases the support surface for the window panel 48 and for L-shaped element 40, as well as stiffening the frame 86 against bending forces.

FIG. 7 illustrates an embodiment 88 which uses an inner frame 90 similar to the frame 12 seen in FIG. 1. The inner frame 90 has been substantially stiffened by interposing a rectangular tube 92 between the window panel 48 and the inner frame 90. The rectangular tube 92 serves to greatly increase the range of window panel thickness which can be used, making this embodiment suitable for exceptionally heavy duty and, when attached to inner frame 90, its upper surface 16 serves as the flange-like supporting base for window panel 48, in conjunction with surface 22 of inner frame 90 which functions as the back wall of the aforementioned L-shaped element.

The rectangular tube 92 forms a quadrilateral frame which is connected to the inner frame 90 by means of fasteners 94.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

11 136,939/2 WHAT IS CLAIMED IS:

1. A blast-protective window frame construction system, comprising: a) an inner window-retaining frame of extruded metal, said frame having in cross-section a first substantially L-shaped window-panel-retaining element, said L-shaped element being able to accommodate window panels of various thicknesses; wherein a flange-like base of said L- shaped element is adapted to at least indirectly support an edge of a window panel, and a back-like wall of said L-shaped element is adapted to at least indirectly support inner surfaces of said window panel, an outer frame, attachable to a building and framing an opening having an inner perimeter larger than the outer perimeter of said window panel, whereby window panels of various thicknesses may project into said opening without obstruction by elements of said outer frame.

2. A blast-protective window according to claim 1 , wherein said window panel attached to said inner frame by strongly adhesive material.

3. A blast-protective window according to claim 1 , comprising a second substantially L-shaped window-panel retaining element, provided with means for attachment of a flange-like base of said second substantially L-shaped element to the flange-like base of said first L-shaped element, with the backlike wall of said second L-shaped element in spaced-apart substantially parallel alignment with the back-like wall of said first L-shaped element, and defining therebetween a space sized to accommodate a pre-determined thickness of said window panel, by virtue of the chosen width of said flangelike base of said second substantially L-shaped window-panel retaining element, said back-like wall of said second L-shaped element being adapted to abut and support outer surfaces of said window panel. 11 136,939/2

4. A blast-protective window according to claim 1 , wherein said flange-like base is provided with means for attachment thereto of at least one retaining striplike element in spaced-apart, substantially parallel alignment with the back-like wall of said first L-shaped element and defining therebetween a space sized to accommodate a predetermined thickness of said window panel, said strip being adapted to abut and support outer surfaces of said window panel.

5. A blast-protective window according to claim 1 , said frame being composed of at least four frame sub-units sequentially attached to each other by right-angle corner units, wherein each of said frame sub-units further comprises a hollowed base sized to receive an arm of said right-angle corner units at each of its ends to form a quadrilateral frame enclosure for said window panel and wherein said hollowed area is positioned to be traversed by at least 90% of the plane of said window panel when said window panel is retained by said L- shaped elements.

6. A blast-protective window according to claim 5, wherein a portion of said frame sub-unit constitutes said L-shaped element. For the Applicant WOLFF, BREGMAN AND GOLLER by: ft I J A