GB1567983A

GB1567983A - Manufacture of plural-pane window assemblies

Info

Publication number: GB1567983A
Application number: GB41161/77A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1976-10-06
Filing date: 1977-10-04
Publication date: 1980-05-21
Also published as: BE859381A; BR7706649A; FR2367179A1; JPS5396245A; IT1116648B; DE2744880A1

Description

(54) MANUFACTURE OF PLURAL-PANE WINDOW ASSEMBLIES (71) I, EDMUND ANTON LEOPOLD, a German citizen of 2461A Warren Parkway, Twinsburg, State of Ohio, United States of America, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to window assemblies of the type including two or more sheets of light-transmitting material supported in spaced relationship and providing an insulating air space between the sheets.

More particularly, the present invention relates to methods and apparatus for the manufacture of plural-pane window assemblies, and to plural-pane window assemblies manufactured in accordance with such methods.

Window assemblies of the type including two or more peripherally bonded, hermetically sealed, air-spaced sheets of lighttransmitting material are known in the art as "insulating glass". A desiccant-filled spacer is commonly positioned between peripheral portions of adjacent sheets, and a pliable bonding material is applied about the spacer structure to peripherally bond and seal the assembly.

The spacer structures used in insulating glass are ordinarily hollow frame-like assemblies of aluminum or galvanized steel.

Manufacturers of insulatng glass fill these hollow frame-like assemblies with desiccant materials and position the freshly filled assemblies between sheets of lighttransmitting material for bonding. The bonding material used to effect peripheral bonding and sealing of the assemblies is typically a butyl or hot-melt or polysulfide material which adhesively bonds the assembly together and hermetically seals the air spaces between adjacent sheets.

In the fabrication of so-called double seal units, beads of butyl sealant are ordinarily applied to opposite sides of a desiccantfilled spacer prior to the spacer's being positioned between two sheets of lighttransmitting material. The edges of assembled units are sealed with a secondary application of sealant which mainly serves to bond components of the unit together, but which also serves as a back-up for the butyl seals formed between the spacer and the sheets. Polysulfides and hot-melts as well as combinations of different sealants are used to effect the secondary seal in double seal units.

Double seal units have the advantages of no direct contact between the spacer and the light-transmitting sheets, and of the butyl beads forming thermal barriers between spacers and the sheets, whereby heat loss through the units is significantly reduced.

Double seal units are also characterized by much longer useful lives than other types of insulating glass units, and are typically guaranteed by their manufacturers for 20 years. The biggest drawback of double seal units lies in the amount of time and effort required for their fabrication, and their attendantly higher cost.

Plural-pane window assemblies are fabricated in accordance with the preferred method of the present invention by first heating a hot-melt sealant material to a temperature at which it can be extruded in a controlled flow through a nozzle. The heated sealant is extruded through a nozzle onto a spacer while the spacer and the nozzle are moving relative to each other along a path of movement, whereby a ribbon of the sealant is bonded to the spacer. The sealant ribbon is substantially U-shaped when viewed in cross-section, and coats opposite sides of the spacer.

Once the sealant has been applied to the spacer, the sealant-coated spacer is positioned between two sheets of light transmitting material, with the opposite, sealant-coated sides of the spacer each facing toward a separate one of the sheets.

When the spacer and the sheets are assembled in this manner, the spacer and the sheets cooperate to define an insulating space between the sheets.

Fabrication of the window assembly is completed by pressing the sheets toward each other to effect good surface contact between the sheets and such portions of the sealant as coat opposite sides of the spacer.

While the assembly is being compressed, it is heated to effect a thorough, continuous bond between the sealant and the sheets, and to seal the insulating space between the sheets.

A significant feature of the present invention lies in its provision of a technique for applying hot-melt sealants to spacers in such a manner that the entire sealant application procedure can be accomplished with one quick pass of each spacer leg through a nozzle passage. A nozzle of novel construction may be utilized. The nozzle has walls which define a substantially U-shaped passage adapted to loosely receive a spacer. A U-shaped nozzle opening is provided in the walls for extruding a U-shaped ribbon of sealant onto a spacer as a spacer leg is moved through the passage. The nozzle may have a valve located near the nozzle opening for controlling the supply of sealant to the opening. Adjustable nozzle components may be provided to regulate the width of the nozzle passage to accommodate spacers of a wide range of sizes. The nozzle body may include adjustment means for moving selected portions of the walls for adjusting the size of the passage to accomodate different sizes of window assembly spacers.

In preferred practice, hot sealant which has been extruded through the nozzle onto a spacer is shaped at a location downstream from the nozzle to effect a desired crosssectional distribution of the sealant on the spacer. The sealant shaping operation is preferably effected by establishing rolling contact between the applied sealant and one or more shaping wheels. The surface portions of the shaping wheel or other shaping means which contact the sealant are preferably maintained at a temperature substantially below that at which the sealant is extruded from the nozzle to assure that the sealant does not adhere to these surface portions.

Apparatus for bonding the sealant to the sheets preferably takes the form of a press having upper and lower sets of rollers. The assembled sandwich of sheets and interposed spacer is passed between the sets of rollers and is compressed during such passage. The window assembly is heated as it travels between the upper and lower sets of rollers by suitable heating means such as infra-red radiation.

The invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an apparatus for rapidly applying sealant to a window assembly spacer and for shaping the applied sealant; Figures 2, 3 and 4 are enlarged sectional views as seen from planes indicated by lines 2-2, 3-3 and 4-4 in Figure 1; Figure 5 is an enlarged perspective view of a portion of the apparatus of Figure 1; Figures 6 and 7 are sectional views as seen from planes indicated by lines 6-6 and 7-7 in Figure 5; Figure 8 is a top plan view of a portion of the apparatus of Figure 5; Figure 9 is a top plan view as seen from a plane indicated by a line 9-9 in Figure 6; Figure 10 is a foreshortened sectional view of a plural-plane window assembly fabricated in accordance with the present invention.

Referring to Figure 1, an apparatus 20 is shown for applying a ribbon of hot-melt sealant to a window assembly spacer 30. The apparatus 20 includes a protective outer housing or enclosure 22. A sensing head 50, an extrusion nozzle 60, and a shaping wheel 110 are supported on the housing 22. When a leg of the spacer 30 is moved along a path of travel indicated by arrows 24, a U-shaped ribbon of hot-melt sealant 26 is extruded onto the spacer 30. Sealant 26 extruded onto the spacer 30 by the nozzle 60 typically has a somewhat rounded cross-sectional configuration as shown in Figure 3. If necessary the shaping wheel 110 effects a re-distribution of the sealant 26, conforming it better to the cross-sectional configuration of the spacer 30, as shown in Figure 4.

The spacer 30 is a conventional, rectangular-frame spacer assembly having four legs 32, 34, 36, 38 which are soldered or otherwise joined at their corner junctures. Each of the legs is hollow and has a crosssectional configuration as shown in Figure 2.

The hollow legs 32, 34, 36, 38 are filled with a suitable desiccant material 40.

The sensing head 50 includes a light source 52 and a light-responsive photocell 54. The source 52 and the photocell 54 are located on opposite sides of the path 24, upstream from the nozzle 60. The source 52 projects a beam of light across the path 24 toward the photocell 54. The presence of a spacer moving along the path 24 interrupts the light beam, and causes a change in the output signal of the photocell 54 indicating the presence of a spacer 30 moving along the path 24 at a location near the nozzle 60. As will be explained, the output from the photocell 54 is preferably used to control the supply of hot-melt sealant to the nozzle 60.

Other conventional sensing systems such as limit switches, proximity sensors, and the like can, of course, be used in place of the described photocell system.

Referring to Figures 5 to 7, the nozzle 60 includes three major components, namely a body 62, a head part 64, and a valve member 66. The head part 64 is movably supported on the body 62 and cooperates with an upstanding end portion 68 of the body 62 to define an adjustable width U-shaped passage 70. A U-shaped nozzle opening 72 opens into the passage 70 for extruding a U-shaped ribbon of hot-melt sealant onto a spacer leg as the spacer leg moves through the passage 70. A bore 74 is formed through the body 62. The nozzle opening 72 communicates with the bore 74.

A conduit passage 76 is formed in the body 62 at a location below the nozzle opening 72 and communicates with the bore 74. The valve member 66 is journalled in the bore 74 and operates to control the flow of hot-melt sealant from the conduit passage 76 to the nozzle opening 72.

Tapered walls 78, 80, 82 are formed on the upstanding end portion 68, on the body 62, and on the head part 64 on opposite sides of the passage 70 to relieve the area of the nozzle opening 72. An enlarged sealant supply bore 84 is formed in the upstanding end portion 68 to assure an adequate supply of sealant to its associated side of the nozzle opening 72. A corresponding supply bore 86 is formed in the body 62 near the other end of the body-carried nozzle opening, as seen in Figure 9. An enlarged supply passage 88 is formed in the head part 64 and communicates with the supply bore 86 to assure an adequate supply of sealant to its associated side of the nozzle opening 72.

A pair of slots 90 are formed through the head part 64. Threaded fasteners 92 extend through the slots 90 and are threaded into holes formed in the body 62. When the fasteners 92 are loosened, the head part 64 is slidable along the tapered walls 80 to adjust the width of the passage 70 to accommodate spacers of a wide range of sizes.

Referring to Figures 6 and 8, the valve member 66 has an elongated, radially extending slot 94 through which hot-melt sealant is transmitted from the conduit passage 76 to the nozzle opening 72. A pair of O-rings 96 prevent the sealant from traveling along the bore 74. A pair of snap rings 98 prevent the valve member 66 from moving axially in the bore 74. The supply of sealant delivered to the nozzle opening 72 is controlled by rotating the valve member 66 so that the slot 94 selectively communicates the conduit passage 76 and the nozzle opening 72. A handle 100 is provided at one end of the valve member 66 to facilitate its rotation. A rotary actuator (not shown) is preferably connected to the opposite end of the valve member 66 for operating the valve member in response to an output signal from the photocell 54. Suitable signal delay circuitry is preferably interposed between the photocell 54 and this rotary actuator to coordinate the initiation of sealant extrusion with the entrance of one end of a spacer leg in the passage 70, and to effect termination of sealant extrusion as the other end of the spacer leg leaves the passage 70.

Pressurized hot-melt sealant at a suitable extrusion temperature of about 350-400"F.

is supplied to the conduit passage 76 through a conduit 102. The conduit 102 communicates with a heated extruder apparatus (not shown) housed within the protective enclosure 22. Inasmuch as suitable apparatus for heating and supplying hot-melt sealant under pressure is well known and forms no part of the present invention, it is not described in detail here.

In some instances it is desirable to use a series of sealant shaping wheels to progressively redistribute sealant on spacer frame legs.

Referring to Figure 10, once the ribbon of sealant 26 has been bonded to and shaped around the legs of the spacer 30, the sealant-coated spacer is inserted between two sheets 170, 172 of light-transmitting material such as glass to form an assembly 174 of window components. The assembled components define an insulating space 176 between the sheets 170, 172, and the sealant 26 forms a thermal barrier between the sheets 170, 172 and the spacer 30.

The assembly 174 is then passed through a press apparatus. The press apparatus includes upper and lower sets of drivingly interconnected rollers. As the assembly passes between the sets of rollers, it is compressed by the rollers and heated rapidly by infra-red lights, or by micro-wave heating, or any other suitable heating technique, to a temperature which is sufficient to re-activate the hot-melt sealant 26 and assure that it bonds thoroughly not only to the sheets but also to the spacer 30.

As will be apparent from the foregoing description, the present invention provides novel methods and apparatus for forming plural-pane insulating glass windows simply and inexpensively, and provides plural-pane window assemblies with improved bonds and seals between their components. Unlike prior processes, proper heating of the sealant for good bonding is assured, first by applying heated sealant directly onto the spacer frame, and second by reheating the assembled window components to reactivate the sealant as the components are subjected to compression.

WHAT I CLAIM IS: 1. A method of manufacturing a pluralpane window assembly of the type including at least two sheets of light-transmitting material separated by a spacer, wherein the spacer and the two sheets cooperate to define an insuulating space between the two sheets, characterized by: (a) heating a hot-melt sealant material to a temperature at which the sealant can be extruded in a controlled flow through a nozzle; (b) extruding the heated sealant through a nozzle onto a spacer while the spacer and the nozzle are moving relative to each other along a path of movement to apply a ribbon of sealant to the spacer with the applied ribbon of sealant being substantially U-shaped when viewed in crosssection and coating opposite sides of the spacer.

(c) positioning the sealant-coated spacer between two sheets of light-transmitting material with the opposite, sealant-coated sides of the spacer each facing toward a separate one of the sheets, and with the spacer and the sheets cooperating to define an insulating space between the sheets; (d) pressing the sheets toward each other to effect good surface contact between the sheets and such portions of the sealant as coat opposite sides of the spacer; and (e) heating the assembly of the sheets and the sealant-coated spacer during such pressing to bond the assembly together and to seal the insulating space between the sheets.

2. The method of claim 1, characterized by the step of shaping the sealant applied to the spacer prior to the positioning of the sealant-coated spacer between the sheets, the shaping effecting a desired crosssectional distribution of the sealant on the spacer.

3. The method of claim 1 or claim 2, characterized in that the spacer has a plurality of elongated, interconnected portions which cooperate to define a frame-like structure, and the heated sealant is extruded onto the elongated spacer portions one at a time.

4. The method of any one of claims 1 to 3, characterized by the steps of concurrently cooling and shaping the sealant applied to the spacer prior to the positioning of the sealant-coated spacer between the sheets.

5. The method of any one of claims 1 to 4, characterized in that the step of extruding the heated sealant is effected using a nozzle having walls which define a substantially U-shaped passage adapted to loosely receive the spacer, and having a U-shaped nozzle opening formed in the walls, and heated sealant is extruded through the nozzle opening toward the spacer as the spacer is moved relative to the nozzle through the passage.

6. The method of any one of claims 1 to 5, characterized by the step of sensing the presence of a spacer moving along the path of movement and controlling the extrusion of sealant through the nozzle in response to the sensed presence of a spacer.

7. Apparatus for extruding heated, hotmelt sealant onto a spacer of the type used between two sheets of light-transmitting material in a plural-pane window assembly, the apparatus comprising: (a) a nozzle body having walls defining a passage of substantially U-shaped crosssection adapted to loosely receive a window assembly spacer; (b) a substantially U-shaped nozzle opening formed through the walls and opening into the passage for extruding heated, hot-melt sealant onto a window assembly spacer as the spacer is moved relative to the nozzle through the passage.

8. Apparatus according to claim 7, characterized in that the nozzle is part of an extrusion means for extruding a heated, hot-melt sealant onto a spacer as the spacer and the extrusion means move relative to each other along a path of movement and for applying the extruded sealant to the spacer in the form of a ribbon which is substantially U-shaped when viewed in cross-section and which coats opposite sides of the spacer; and by bonding means for compressing and heating an assembly comprising the sealant-coated spacer interposed between two opposed sheets of lighttransmitting material to effect good surface contact between the sheets and such portions of the sealant as coat opposite sides of spacer, to bond the assembly together, and to seal an insulating space defined between the sheets.

9. The apparatus of claim 8, characterized by shaping means for effecting a desired cross-sectional distribution of the sealant applied to the spacer prior to the spacer's being interposed between the two opposed sheets.

10. The apparatus of claim 9, characterized by cooling means for maintaining such portions of the shaping means as contact the sealant at a temperature substantially below that at which the sealant is extruded from the extrusion means.

11. The apparatus of any one of claims 7 to 10, wherein the nozzle includes means for adjusting the width of the passage to accommodate spacers of different widths.

12. The apparatus of any one of claims 7 to 10, wherein the nozzle body includes adjustment means for moving selected portions of the walls for adjusting the size of the passage to accommodate different sizes of window assembly spacers.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. WHAT I CLAIM IS:

1. A method of manufacturing a pluralpane window assembly of the type including at least two sheets of light-transmitting material separated by a spacer, wherein the spacer and the two sheets cooperate to define an insuulating space between the two sheets, characterized by: (a) heating a hot-melt sealant material to a temperature at which the sealant can be extruded in a controlled flow through a nozzle; (b) extruding the heated sealant through a nozzle onto a spacer while the spacer and the nozzle are moving relative to each other along a path of movement to apply a ribbon of sealant to the spacer with the applied ribbon of sealant being substantially U-shaped when viewed in crosssection and coating opposite sides of the spacer.

13. The apparatus of claim 12, characte

rized by: (a) the nozzle body includes first and second members, each of which defines different portions of the passage walls, and each of which has structure defining different portions of the nozzle opening; and (b) the adjustment means includes structure for selectively relatively positioning the first and second members.

14. A plural-pane window assembly, comrising: (a at least two spaced, opposed sheets of light-transmitting material; (b) a spacer interposed between peripheral portions of the opposed sheets and cooperating with the sheets to define an insulating space between the sheets; (c) a ribbon of hot-melt sealant bonded to the spacer and to the sheets and sealing the insulating space, the ribbon being substantially U-shaped when viewed in crosssection and having first and second leg portions interconnected by a base portion; (d) the first leg being interposed between one side of the spacer and peripheral portions of one of the sheets; (e) the second leg being interposed between the other side of the spacer and peripheral portions of the other sheet; (f) the third leg portion extending perimetrically around the spacer and transversely between the sheets; (g) the bond between the sealant and the spacer having been formed by extruding the sealant onto the spacer prior to the spacer's having been interposed between the two sheets; and (h) the bond between the spacer and the two sheets having been formed by concurrently compressing and heating the assembly of the sheets and the sealant-coated spacer. A

15. A method according to claim 1, substantially as hereinbefore described.

16. Apparatus according to claim 7, substantially as hereinbefore described with reference to the accompanying drawings.

17. A plural-pane window assembly, whenever manufactured by a method in accordance with any one of claims 1 to 6 and 15.