Insulating glazing unit, in particular for a climate chamber

Abstract

An insulating glazing includes two glass sheets spaced apart by an air- or gas-filled cavity, at least one spacer arranged at a periphery of the glass sheets and that keeps the glass sheets spaced apart, one of the spacers being transparent, made of transparent plastic and placed on one of the sides of the glazing, and a first leaktight barrier that is leaktight to water, formed by a structural seal, a material of which is watertight, and a second leaktight barrier that is leaktight to gases and to water vapor, the leaktight barriers being made of transparent material, wherein the spacer includes on at least one of its internal and external faces, the internal and external faces being respectively facing and on the opposite side from the gas-filled cavity, a coating which is thin and constitutes the second transparent barrier, the coating and the transparent spacer forming a single assembly.

Claims

1. An insulating glazing comprising at least two glass sheets that are spaced apart by at least one air- or gas-filled cavity, at least one spacer that is arranged at a periphery of the two glass sheets and that keeps the two glass sheets spaced apart, the at least one spacer being a transparent spacer made of transparent plastic and placed on at least one of the sides of the glazing, and a first leaktight barrier that is leaktight to water, formed by at least one structural seal, a material of which is watertight, and a second leaktight barrier that is leaktight to gases and to water vapor, the first and second leaktight barriers being made of transparent material, and wherein the transparent spacer comprises on at least one of its internal and external faces, the internal face and facing the gas-filled cavity and the external face being opposite the internal face and facing an exterior of the insulating glazing, a transparent thin coating which has a thickness of at most 500 m and constitutes the second transparent leaktight barrier that is leaktight to gases and to water vapor, the transparent thin coating and the transparent spacer forming a single assembly.

2. The glazing as claimed in claim 1, wherein the transparent thin coating is a film added to the spacer or a deposited thin layer.

3. The glazing as claimed in claim 1, wherein the transparent thin coating is made of silicon oxide, or aluminum oxide or polysilazane.

4. The glazing as claimed in claim 1, wherein the transparent thin coating covers the internal and/or external face, and in addition corners of the internal and/or external face by extending onto spacer-fastening faces which are parallel to the glass sheets, or the transparent thin coating covers all the faces of the spacer.

5. The glazing as claimed in claim 1, wherein the transparent spacer is made of plastic of SAN (styrene-acrylonitrile) type or of PETg (glycolized polyethylene terephthalate) or of PMMA (polymethyl methacrylate), or of polycarbonate.

6. The glazing as claimed in claim 1, wherein the transparent spacer is bulk or hollow.

7. The glazing as claimed in claim 1, wherein the structural seal positioned at an interface between each glass sheet and the opposite face of the spacer, and is made of an adhesive and watertight transparent material.

8. The glazing as claimed in claim 1, further comprising a supplementary leaktight barrier which is positioned at an interface between each fastening face of the spacer and each glass sheet, and/or limited to perpendicular to an interface between corners of the spacer and the glass sheets and/or arranged over an entire width separating the two glass sheets on an outer face of the spacer.

9. The glazing as claimed in claim 1, further comprising a supplementary leaktight barrier which is positioned at an interface between each fastening face of the spacer and each glass sheet, being abutted and aligned with the structural seal, a thickness of the supplementary barrier being equivalent to that of the structural seal.

10. The glazing as claimed in claim 1, wherein the glazing is a double glazing or triple glazing.

11. The glazing as claimed in claim 1, wherein the glazing is provided with one or more low-emissivity coatings and/or an anti-fog or anti-frost layer.

12. A door comprising a glazing as claimed claim 1.

13. A climate-controlled unit comprising at least one door as claimed in claim 12.

14. The glazing as claimed in claim 1, wherein the thickness of the transparent thin coating that is leaktight to gases and to water vapor is between 2 nm and 200 m.

15. The glazing as claimed in claim 2, wherein the deposited thin layer is deposited by a magnetron process, evaporation process, or else a wet-coating process.

16. The glazing as claimed in claim 7, wherein the structural seal is made of acrylic or silicone, which is optionally crosslinkable under the action of ultraviolet rays.

17. The glazing as claimed in claim 9, wherein the thickness of the supplementary barrier is from a few micrometers to 2 mm.

18. A climate-controlled unit comprising a plurality of glazings as claimed in claim 1, the plurality of glazings being placed side-by-side with one another, the transparent spacers associated with the plurality of glazings being placed at least on the sides abutted to one another of the glazings.

19. The glazing as claimed in claim 1, wherein the second leaktight barrier is provided on the internal face.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention is now described using merely illustrative and non-limiting examples of the scope of the invention, and with regard to the appended drawings, in which:

(2) FIG. 1 illustrates a perspective view of a front of a refrigerated unit incorporating a plurality of glazings according to the invention;

(3) FIG. 2 is a partial schematic cross-sectional and top view of a glazing of the invention;

(4) FIGS. 3a to 3d are schematic views of positioning variants of the thin leaktight coating of a spacer according to the invention, it being possible for the spacer to be bulk or hollow.

DETAILED DESCRIPTION

(5) The figures are not to scale for the sake of readability.

(6) The climate-controlled unit 1 schematically illustrated in FIG. 1 comprises a plurality of doors 2 each comprising an insulating glazing 3 according to the invention.

(7) The unit is for example a refrigerated chiller unit intended to be installed in a store aisle. It is thus possible, according to the invention, to form a unit with a row of doors that are laterally abutted vertically along their edge faces.

(8) In the case of a chiller unit/display case, since leaktightness is less critical than for a freezer unit, the door of the invention comprising the insulating glazing of the invention has no need to comprise vertical jambs forming a frame and provided with thick seals at the junction of two abutted doors/glazings. The glazing of the invention thus allows, because of the transparency of its vertical edges, a continuous transparent area to be achieved when glazings are placed side-by-side via their edge faces.

(9) Each insulating glazing comprises at least two glass sheets that are held parallel and spaced apart by a frame the opposite vertical portions of which, in the mounted position of the glazing, are transparent.

(10) The front of the glazings and therefore of the unit is thus devoid of any structural frame and has a virtually smooth glass-wall-like appearance. In this way vision area is increased.

(11) Only the transparent vertical portion of the frame of the glazing, i.e. the portion corresponding to the invention, will be described below, the horizontal portions generally being formed by conventional interlayer means and leakfight means that are not transparent. Likewise, the door that incorporates the glazing, the hinging means, the profiles for supporting and hiding the hinging means, and the type of handle will not be described.

(12) FIG. 2 illustrates a partial top view of the insulating glazing 3 showing the transparent vertical inner portion 4 of the frame. The insulating glazing illustrated is a double glazing with two glass sheets. In the case of a triple glazing with three glass sheets, the glazing would comprise two transparent portions 4 according to the invention.

(13) The glazing 3 comprises two glass sheets 30 and 31 that are parallel and spaced apart by means of an interlayer element or spacer 5.

(14) The glass sheets 30 and 31 are preferably made of tempered glass. The thickness of each of the glass sheets is between 2 and 5 mm, and is preferably 3 or 4 mm in order to minimize the overall weight of the glazing and to optimize the transmission of light.

(15) The glass sheets are separated from each other by the spacer 5 in order to produce, therebetween, a volume forming a gas-filled cavity 32.

(16) The gas-filled cavity 32 has a thickness of at least 4 mm and is modified depending on the desired performance in terms of the heat-transfer value U, but is no thicker than 16 mm, or even than 20 mm.

(17) The gas-filled cavity is filled with air or, preferably, in order to increase the level of insulation of the glazing, a noble gas, chosen from argon, krypton, xenon, or a mixture of these various gases, the noble gas making up at least 85% of the gas mixture filling the cavity. For an even further improved U value, it is preferable for the cavity to be filled with at least 92% krypton or xenon.

(18) The spacer 5 preferably has a low thermal conductivity, having a thermal conductivity coefficient of at most 1 W/m.Math.K, preferably less than 0.7 W/m.Math.K, and even less than 0.4 W/m.Math.K.

(19) The spacer has a body made of transparent plastic, of styrene-acrylonitrile (SAN) or polypropylene type for example.

(20) The spacer 5 is of generally parallelepipedal shape and has four faces, a face called the internal face 50 facing the gas-filled cavity, an external opposite face 51 facing the exterior of the glazing, and two what are called fastening faces 52 and 53 facing the respective glass sheets 30 and 31. The spacer may in particular have, on its internal face 50, a profile with sections cut toward the corners (not illustrated). The spacer may be hollow as illustrated schematically in FIG. 2.

(21) The spacer 5 extends lengthwise (here not shown) over the entire length of each of the at least vertical sides of the glazing.

(22) The spacer has a width (dimension transverse to the general faces of the glass sheets) equivalent to the desired spacing of the glass sheets.

(23) The spacer has a thickness, distance separating the internal 50 and external 51 faces (between the edge of the glazing and the gas- or air-filled cavity), which is equivalent to the width if the spacer has a square cross section, or which may in particular be smaller.

(24) Preferably, the spacer has a thickness of between 3 and 16 mm between glass and gas-filled cavity.

(25) The spacer 5 is fastened by adhesive bonding via its fastening faces 52 and 53 against the respective internal faces 30A and 31A of the glass sheets 30 and 31, by means of a structural seal 6 that furthermore provides watertightness.

(26) The material of the structural seal 6 is transparent and watertight, for example made of silicone or acrylic.

(27) The structural seal 6 is for example a double-sided adhesive tape.

(28) The thickness (dimension extending between the spacer and the glass sheets) of the structural seal 6 is between a few micrometers and 2 mm depending on the nature of the material as regards its bonding ability in particular.

(29) The structural seal 6 extends over the length of the spacer on one side of the glazing, and along a limited width of each fastening face 52 and 53 of the spacer.

(30) The structural seal 6 is positioned, with regard to FIG. 2, so as to open from the external side of the glazing.

(31) Preferably, the spacer 5 via its external face 51 and each structural seal 6 at the interface with each glass sheet are coplanar with the edge of the glass sheets.

(32) The glazing furthermore comprises a transparent barrier that is leaktight to gases and to water vapor.

(33) According to the invention, the barrier that is leaktight to gases and to water vapor consists of a thin coating 54 made of a material that is leaktight to gases and to water vapor attached to the internal face 50 and/or external face 51 of said spacer.

(34) With regard to FIG. 2, the thin coating 54 is attached to the internal face 50 of the spacer 5.

(35) With regard to the variant from FIG. 3a, the coating 54 may cover one of the internal or external faces and the corners of the spacer by extending onto the fastening faces 52 and 53.

(36) FIG. 3b illustrates the variant for which the coating 54 is both on the internal face 50 and external face 51.

(37) FIG. 3c corresponds to FIG. 3b, the coating 54 extending onto the fastening faces.

(38) FIG. 3d illustrates a variant for which the coating covers all the faces of the spacer.

(39) This coating is thin, preferably with a thickness of between 2 nm and 200 m.

(40) The thin coating is a film added to the spacer or a deposited thin layer. Its thickness is above all linked to the type of material used and to the process for manufacturing same.

(41) In the case of a deposited thin layer, this layer is deposited by any technique, such as by a magnetron process, evaporation, or else a wet-coating process.

(42) The transparent thin coating that is leaktight to gases and to water vapor is, as a preferred example, made of silicon oxide, or aluminum oxide or else polysilazane.

(43) Owing to the very thin thickness of the coating 54, when this is incorporated with the spacer, it is imperceptible to the naked eye, which does not disrupt the transparent visual impression that the entire glazing must give, in particular at the join of two glazings abutted by their vertical sides comprising the transparent spacers.

(44) Furthermore, the glazing advantageously comprises supplementary means 7 that are leaktight to gases and to water vapor, which are positioned at least at the interface and/or perpendicular to the interface between each glass sheet 30 and 31 and the fastening faces 52 and 53 of the spacer.

(45) FIG. 2 illustrates the preferred example of the leaktight means 7 arranged at the interface between each glass sheet 30 and 31 and the fastening faces 52 and 53 of the spacer.

(46) The leaktight means 7 extend on the one hand over the length of the spacer, and on the other hand along a portion of the width of the spacer, being abutted and aligned with each watertight structural seal 6.

(47) The supplementary leaktight means 7 open from the internal side of the glazing facing the gas-filled cavity 32, preferably without going beyond the internal face 50 of the spacer.

(48) The leaktight means 7 are preferably made of butyl rubber.

(49) The leaktight means 7 have a thickness equivalent to that of the structural seal 6.

(50) This embodiment from FIG. 2 makes it possible to place the spacer coplanar with the edge of the glass sheets. Consequently, the transparent portion 4 of the frame thus created provides leaktightness while very greatly minimizing the visual impact, no thickness of sealing material indeed being present transversely to the glass sheets, between the glass sheets and at the edge of the glazing.

(51) The function of leaktightness to gases and to water vapor is guaranteed over the entire edge face of the glazing with no visual disturbance owing, on the one hand, to the transparent ultra-thin coating 54 attached to the edge of the spacer and to the thin thickness of the supplementary leaktightness means 7 limited to the interface or perpendicular to the to interface between the spacer and the glass sheets.