IE20050775U1 - A process for producing double glazed glass panels - Google Patents

Abstract

ABSTRACT This invention relates to a process for efficiently and seamlessly producing double glazed glass panels of the type comprising an outer and an inner glass sheet spaced- apart by a hollow spacing frame. The process described utilizes highly automated procedures and machinery so as to maximise the quantities of double glazed glass panels produced whilst at the same time minimising glass wastage.

Description

“A Process for Producing Double Glazed Glass Panels” The present invention relates to a process for preparing insulating double glazed glass panels of the type comprising a pair of glass sheets separated by a spacing frame. The double glazed glass panels produced by the process are particularly suitable for use in windows and doors.

The manufacture of double glazed glass panels is a time consuming process, which process is complicated by the varying size requirements of the double glazed glass panels produced. For example, in instances involving the preparation of double glazed glass panels from larger base glass sheets it is necessary to accurately cut the larger base glass sheet into smaller individual glass sheets of a desired size. A pair of these individual glass sheets are then typically mounted and sealed either side of a spacing frame to form the double glazed glass panel.

However, the accurate cutting of a large base glass sheet into smaller glass sheets and then subsequently preparing large quantities of such small glass sheets for double glazing is highly time consuming and typically results in a large amount of glass wastage. There is therefore a need for a process for producing double glazed glass panels which minimises glass wastage whilst at the same time maximises the efficient preparation of individual glass sheets for double glazed glass panels. The present invention is therefore directed to such a process.

It is therefore an object of the present invention to provide a process for producing double glazed glass panels which goes someway toward overcoming at least the above disadvantages, and/or which will provide the public and/or industry with a useful choice.

It is acknowledged that the term ‘comprise’, under varying jurisdictions may be provided with either an exclusive or inclusive meaning. For the purpose of this specification, and unless othen/vise noted explicitly, the term comprise shall have an inclusive meaning ~ i.e. that it may be taken to mean an inclusion of not only the IEOSO775 listed components it directly references, but also other non-specified components.

Accordingly, the term ‘comprise’ is to be attributed with as broad an interpretation as possible within any given jurisdiction and this rationale should also be used when the terms ‘comprised’ and/or ‘comprising’ are used.

Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only.

Statements of Invention According to the invention there is provided a process for preparing a double glazed glass panel of the type comprising a pair of glass sheets separated by a spacing frame, the process comprising the steps of: (a) cutting a hollow elongate length of material to a desired length, (b) bending the elongate length of material intermediate its ends to form a spacing frame having outwardly directed front and rear faces and outer and inner peripheral edges; (c) joining the free ends of the spacing frame together; (d) drilling a hole through the outer peripheral edges of the spacing frame and injecting a desiccant into the spacing frame through the hole; (e) sealing the hole; (f) applying a butyl seal around the front and rear faces of the spacing frame; (g) delivering the spacing frame to the panel forming station; (n) preparing a pattern of breaks to be made on a base glass sheet; ‘IE050775 (i) aligning the base glass sheet on a conveyor so that any breaks to be made which extend fully across the base glass sheet perpendicular to the direction of movement of the base glass sheet along the conveyor are performed first; (j) spraying a band of oil on a surface of the base glass sheet corresponding to the pattern of breaks; (k) scoring the base glass sheet along the band of oil to form break lines; (I) breaking the base glass sheet along the scores to fonn a plurality. of glass sheets of a desired size, which breaking comprises the steps of: i. breaking the base glass sheet along all complete transverse break lines to fonn a plurality of glass sheets, which transverse break lines extend fully across the base glass sheet in a direction perpendicular to the direction of movement of the base glass sheet along the conveyor; ii. separating the glass sheets; iii. breaking the glass sheets along any longitudinal break lines, which break lines extend fully along the intermediate glass sheets in the direction of movement of the glass sheets along the conveyor, iv. separating the glass sheets resulting from step(iii), and v. breaking the glass sheets along any unbroken transverse break lines to form a plurality of glass sheets of a desired size; (m) chamfering the edges of the glass sheets; (n) washing and drying the glass sheets; |Eo5o775 (o) passing the glass sheets through a furnace for a predetennined period of time to temper the glass sheets; (p) cooling the glass sheets prior to delivery to the panel forming station; (q) at the panel forming station, securing a spacing frame by its rear face to a facing surface of one of a pair of the glass sheets such that the glass sheet projects outwardly of the outer peripheral edges of the spacing frame; ’ (r) delivering the pair of glass sheets to a gas filled chamber, in which gas filled chamber a facing surface of the other of the pair of glass sheets is secured to the front face of the spacing frame whilst at the same time a cavity defined between the inner peripheral edges of the spacing frame is filled with an insulating gas present in the gas filled chamber; (s) applying a seal around a sealant channel formed between the two glass panes and outwardly from the periphery of the spacer frame to form a double glazed glass panel.

The present invention provides a seamless and efficient method for producing double glazed glass panels, which method due to its reliance on highly automated procedures minimizes reliance on human labour and intervention throughout the production process. Accordingly, the present invention will result in a production output which exceeds prior art methods for producing double glazed glass panels. Furthermore, the steps associated with breaking each base glass sheet into smaller glass sheets of a desired size for the double glazed glass panels will significantly minimise glass wastage. Such a reduction in glass wastage will significantly reduce production costs associated with the double glazed glass panels, which is particularly advantageous.

In one embodiment of the invention the edges of each glass sheet are chamfered by a pair of endless belts, each belt secured around a pair of spaced apart rotatable axles and disposed at an angle relative to one another to form a V-shape having an open lEo5o775 mouth facing the edges of the glass sheet so that when the open mouth is pushed against the glass sheet and the belts are rotated by the axles the belts slide against a front and a rear facing edge of the glass sheet at the same time.

The provision of belts for chamfering both front and rear facing edges of a glass sheet at the same time is advantageous as it will significantly reduce the length of time required to chamfer all of the edges of a single glass pane.

Preferably, the belts in each pair of belts are positioned one offset forward of the other, the pair of belts being moveable around the periphery of the glass sheet.

In another embodiment of the invention, the glass sheet is chamfered by a plurality of pairs of endless belts, each pair arranged in the V-shape.

The provision of a plurality of pairs of belts will further reduce the length of time required to chamfer all of the edges of a single glass pane.

Preferably, the angle between each pair of connected belts is adjustable.

The ability to alter the angle between each pair of belts will enable glass sheets of various thicknesses to be chamfered.

In one embodiment of the invention, water is sprayed onto the glass sheets during chamfering of the glass sheets.

In one embodiment of the invention, the longitudinal break lines are broken by a longitudinal break line breaking machine comprising a breaking pin located proud of a pair of spaced apart pinch bars. which pinch bars move up from underneath the base glass sheet when on the conveyor to engage the glass sheet either side of a specific longitudinal break line so as to push the glass sheet up against the breaking pin to break that base glass sheet along that longitudinal break line.

Preferably, the longitudinal break line breaking machine is mounted on the conveyor and moves across the conveyor in a direction perpendicular to the direction of |Eo5o775 movement of the glass sheet along the conveyor.

In a preferred embodiment of the invention, the pattern of breaks is generated by a computer system running computer software programs, which, computer system in response to input received from computer operators to generate the required break patterns.

The provision of a computing software for quickly generating break patterns in the base glass sheets will enhance the efficiency and accuracy of the breaks made, as well as further minimising glass wastage due to errors which are invariably made when this process is done by human operators alone.

Preferably, the input received corresponds to specific orders for double glazed glass panels received from customers, which input is batch processed by the computing system to generate the required break patterns.

In one embodiment of the invention, each base glass sheet is broken into separate glass sheets of a desired size on a horizontal oonveyor, which glass sheets of a desired size are subsequently conveyed once cut from the base glass sheet on a substantially vertical conveyor for assembly into double glazed glass panels.

Preferably, the vertical conveyor has a conveying surface which is inclined at an angle of six degrees to the vertical.

Brief Description of the Drawings Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only and with reference to the accompanying drawings in which: Fig. 1 is a perspective view of one construction of double glazed glass panel according to the invention; Fig. 2 is a perspective cut-away view of the double glazed glass panel lEo5o775 shown in Fig. 1; Fig. 3 is a cross-sectional diagrammatic view of Fig. 1; Figs. 4 to 7are perspective views showing the progressive formation of the double glazed glass pane shown in Figs. 1 to 3; Figs. 8 to 11 are perspective views showing progressive the formation of a spacing frame used to form the double glazed glass pane shown in Figs. 1 to 3; ’ Figs. 12 to 13 are cross-sectional diagrammatic views showing the spacing frame illustrated in Fig. 11 being injected with a desiccant; Fig. 14 to 27 inclusive are perspective views of an apparatus used for producing the double glazed glass panels as shown in Figs. 1 to 3.

Detailed Description of the Drawings Referring to the drawings and initially to Figs. 1 to 3 thereof, there is illustrated a double glazed glass panel, indicated generally by the reference numeral 1, produced according to the present invention, which double glazed glass panel comprises an outer glass sheet 2 spaced apart from an inner glass sheet 3 by a hollow spacing frame 4.

Fig. 2 shows perspective cut away view of the double glazed glass pane shown in Fig. 1, again identified by the reference numeral 1 with parts similar to those described already identified by the same reference numerals. In the instance shown. the spacing frame 4 comprises an outwardly directed front facing surface 5, an outwardly directed rear facing surface 6, an outer peripheral edge 9 and an inner peripheral edge 10, which inner peripheral edge 10 comprises a plurality of diffusion holes 11. The glass sheets 2, 3 are secured to the spacing frame 4 by a butyl seal 7 which is applied to the front and rear facing edges 5, 6 of the spacing frame 4.

Located within the spacing frame 4 is a desiccant 8, which desiccant absorbs |E050775 moisture accumulating within a cavity 12 (see Fig. 3) defined between the inner peripheral edges 10 of the spacing frame 4. A layer of sealant 13 is applied around the outer peripheral edge 9 of the spacing frame 4 between the two glass panes 2, 3.

Referring briefly to Figs. 4 to 7, again with like parts using the same numeral identification system of Figs. 1 to 3, a double glazed glass panel 1 according to the invention is formed as follows. Fig. 4 shows the spacing frame 4 adhered to a facing surface of an inner glass sheet 3, which glass sheet 3 has been previously cut to a desired size. As shown, the peripheral edges of the glass sheet 3 projects outwardly of the outer peripheral edge 9 of the spacing frame 4. Fig. 5_ shows an outer glass sheet 2 being adhered to the spacing frame 4 to form the double glazed panel 1 shown in Fig. 6. Finally, a layer of sealant 13 is applied around the outer peripheral edge 9 of the spacing frame to produce a double glazed glass panel according to the invention.

Referring briefly to Figs. 8 to 13, again with like parts using the same numeral identification system of Figs. 1 to 3, the formation of a spacing frame 4 is shown.

Fig. 8 shows a hollow length of material which is cut to a desired length, which hollow length of material comprises a plurality of diffusion holes 11. The length of material is then bent intermediate its ends to form a spacing frame 4, which bending is shown in Figs. 8 to 11. With specific reference to Fig. 11, the ends of the spacing frame 4 are then joined together.

Fig. 12 shows holes being drilled through the outer peripheral edge 10 of the spacing frame 4 whilst Fig. 13 shows a desiccant being injected through the holes into the spacing frame 4. The drilled holes are sealed once a desired quantity of the desiccant has been injected into the spacing frame 4.

Figs. 14 to 16 inclusive show, in broad outline, an apparatus for producing a double glazed glass panel according to the invention, which apparatus is indicated generally throughout these figures together by the reference numeral 100. Shown in Fig. 14 is a continuous horizontal conveyor 101, and in Figs. 15 and 16 is a continuous vertical conveyor 102, which conveyors 101,102 deliver glass sheets lEo5o775 through the apparatus 100 to facilitate their assembly into double glazed glass panels according to the invention. The vertical conveyor 102 has a conveying surface which is inclined at an angle of about six degrees to the vertical to enable glass sheets to be retained thereon for conveying through the apparatus 100.

Detailed descriptions, where necessary, of the stations and the processes carried out by the apparatus,10O are illustrated in Figs. 17 to 30.

Initially however, a pattern of transverse and horizontal break lines to be made on a base glass sheet is prepared, which pattern when followed will minimise glass wastage during breaking of the base glass sheet whilst at the same time maximizing throughput. Such break patterns will typically be generated by a computer system running computer software programs, such as computer aided design (CAD) applications. Such programs will, in response to input received from computer operators, generate the required break patterns. The input received from the computer operators will be data corresponding to specific orders for double glazed glass panels received from customers, and such data will be batch processed by the computing system and its associated software to generate the required break patterns, which patterns are then transmitted to machinery associated with the apparatus 1 and applied to the base glass sheets as they move through the apparatus 100.

With reference to Figs. 17 to 21, there is shown separate stations of that part of the apparatus 100 illustrated in Fig. 14.

Referring initially to Fig. 17, there is illustrated a base glass sheet placement station, indicated generally by the reference numeral 110, comprising an overhead gantry 113 slideably mounting a gantry crane 114. A glass sheet gripping device 115 depends from the gantry crane 114, which glass sheet gripping device 115 comprises a plurality of suction cups 116. Also shown is a rack 111 for a plurality of base glass sheets 112.

In operation, the gantry crane 114 moves along the overhead gantry 113 into a position enabling the suction cups 116 to releasably grip a single base glass sheet 112 in the rack 111. The base glass sheet 112 is then removed from the rack 111 by the gripping device 115 as it moves along the overhead gantry 113 to a glass lEo5o775 -10.. sheet intake surface 118 which is associated with the conveyor 101. The glass sheet intake surface 118 pivots up on its side at an angle to the conveyor 101 under the action of a pneumatically operated ram 117 to receive the glass sheet 112, which glass sheet 112 is then released from the gripping device 115. The glass sheet intake surface 118 then pivots down to align the base glass sheet 112 on the conveyor 101 such that any breaks to be made which extend fully across the base glass sheet 112 perpendicular to the direction of movement of the base glass sheet 112 along the conveyor 101 are performed first. Once placed on the conveyor the base glass sheet 112 is transferred to a glass scoring station 120 (see Fig. 18).

Referring now to Fig. 18, there is illustrated the scoring station 120 comprising an overhead gantry 121 along which an oil discharge head 122 and a scoring blade 123 move. In operation, as the glass sheet 112 moves underneath the overhead gantry 121 a band of oil is sprayed onto it according to a pre-prepared pattern of transverse and horizontal break lines. The base glass sheet 112 is then subsequently scored along the band(s) of oil, which, in the instance shown, forms complete transverse break lines 124(a), longitudinal break line 124(b) and an incomplete transverse break line 124(c).

It should be appreciated that the complete transverse break lines 124(a) extend fully across the base glass sheet 112 in a direction perpendicular to the direction of movement of the base glass sheet 112 as it moves along the conveyor 101. It should further be appreciated that the longitudinal break lines 124(b) extend along the base glass sheets 112 in the direction of movement of the glass sheets along the conveyor, and any incomplete transverse break lines 124(c) will extend only partially across the base glass sheet 112 in a direction perpendicular to the direction of movement of the base glass sheet 112 along the conveyor 101.

It should be clearly understood that the specific locations of the longitudinal and transverse break lines scored on any glass sheet will vary according to the requirements of a specific double glazed glass panel to be produced. The break lines scored define the dimensions of any smaller glass sheets, as well as any waste glass sheets, to be cut from the base glass sheet 112. Once the break lines have been completed the base glass sheet 112 is transferred to a breaking IE050775 _ 11 _ station 130 (see Fig. 19 and 20).

Referring now to Figs. 19 and 20, there is illustrated a breaking station 130 for breaking the base glass sheet 112 along the break lines 124 to form a plurality of separate glass sheets of a desired size. The breaking station 130 comprises a complete transverse break line breaking machine, indicated generally by the reference numeral 131, a longitudinal break line breaking machine, indicated generally by the reference numeral 132, and an unbroken transverse break line breaking machine, indicated generally by the reference numeral 133.

The complete transverse break line breaking machine 131 comprises a transverse break bar 134 which moves up and down through the conveyor 101 between a pair of transverse overhead crossbars 135 which are located proud of the break bar 134. In operation, the break bar 134 moves underneath the base glass sheet 112 to engage it in the region of a transverse break line 124(a) so as to push the base glass sheet 112 up against the transverse overhead crossbars 132 to apply a breaking force to break the base glass sheet 112 along that specific transverse break line 124(a). The base glass sheet 112 is then iteratively moved along the conveyor 101 over the break bar 134 until all complete transverse break lines 124(a) have been broken.

In the instance shown, the base glass sheet 112 is broken along all complete transverse break lines 124(a) by the complete transverse break line breaking machine 131, which breaks the base glass sheet 112 into a plurality of glass sheets 125(a)-(c).

The glass sheets 125(aHc) are then separated and conveyed along the conveyor 101 in the direction indicated generally by the reference numeral 136 to the longitudinal break line breaking machine 132.

The longitudinal break line breaking machine 132 is mounted on the conveyor 101 and moves along a recess 137 in the conveyor 101 in a direction perpendicular to the direction of movement of the glass sheet 112 along the conveyor 101. The longitudinal break line breaking machine 132 comprises a breaking pin 138 spaced apart proud of a pair of pinch bars 139, which pinch bars 139 move up and down relative to the conveyor 101 to meet the breaking pin 138 so that the breaking pin 138 bisects the pinch bars 139. in operation, the pinch bars 139 move upwards from IE050775 underneath the base glass sheet 112 so as to engage it either side of the longitudinal break line 124(b) and push it up against the breaking pin 138 to apply a breaking force to break the base glass sheet 112 along that longitudinal break line 124(b). The longitudinal break line breaking machine 132 slides along the recess 137 and pinches the glass sheet 112 where necessary to break all longitudinal break lines.

In the instance shown, the base glass sheet112 is broken along the longitudinal break line 124(b) by the longitudinal break line breaking machine 132 to break the glass sheet 125(c) into separate smaller glass sheets 125(c) and 125(d). All of the glass sheets 125(a)-(d) are then separated and conveyed along the conveyor 101 in the direction indicated generally by the reference numeral 136 to the unbrokentransverse break line breaking machine 133 (see Fig. 20).

The unbroken transverse break line breaking machine 133 operates identically to the longitudinal break line breaking machine 132 in order to break all remaining unbroken transverse break lines 124(0). In the instance shown, the base glass sheet 112 is finally broken along the unbroken transverse break line 124(c) to break the glass sheet 125(d) into separate glass sheets 125(d) and 125(e). All of the glass sheets 125(a)-(e) are then separated and conveyed one after another along the conveyor 101 in the direction indicated generally by the reference numeral 136 to a glass sheet rotating station 140 (see Fig. 21). It should be appreciated that the glass sheet 125(e) has, in the instance shown, been discarded as waste.

Referring now to Fig. 21, there is illustrated a glass sheet rotating station, indicated generally by the reference numeral 140, for tilting each of the glass sheets 125(a)- (d) received from the breaking station 130 from a horizontal position on the conveyor 101 to a substantially upright position suitable for onward delivery through the apparatus 100 on a vertical conveyor 102 (see Fig. 21), which vertical conveyor 102, as previously mentioned, has a conveying surface which is inclined at an angle of six degrees to the vertical.

The remaining stages in the process will now be described with reference to glass sheets 125(a) and 125(b) only.

|E050775 Once placed on the vertical conveyor 102 each of the glass sheets 125(a),(b) is delivered to a glass sheet chamfering station, indicated generally by the reference numeral 150.

Referring now to Fig. 22, there is illustrated the glass sheet chamfering station 150 which chamfers, or rounds, the edges of the glass sheets 125(a),(b). With brief reference to Fig. 23, the chamfering station 150 comprises a plurality of pairs of endless belts 151,152,153,154 each belt secured around a pair of spaced apart rotatable axles 151(a),152(a),153(a),154(a) and disposed at an angle relative to one another to each form a V-shape having an open mouth, each open mouth indicated generally by the reference numerals 151(b),152(b),153(b),154(b) respectively, which face the edges of the glass sheet 125(a),(b). it should be appreciated that the angle between the individual belts in each pair of belts may be adjusted depending on the thickness of the glass being chamfered.

In the instance shown, the belts in each pair of belts 151,152,153,154 are positioned one offset fom/ard of the other and the pair of belts 151,152,153,154 are also moveable around the periphery of the glass sheets 125(a),(b). Accordingly, when the belts are pushed against the glass sheet 125(a),(b), and are rotated at high speed by the axles 151(a),152(a),153(a),154(a), they slide against edges of the glass sheets 125(a),(b) at the same time to chamfer them. Water is sprayed against the glass sheets as they are being chamfered.

Referring to Fig. 24, the glass sheets 125(a),(b) are then transferred along the vertical conveyor 102 through a washing and drying station, indicated generally by the reference numeral 160, to sterilize the glass sheets 125(a),(b). Once the glass sheets 125(a),(b) have been dried they are then manually removed from the vertical conveyor 102 by operating personnel and placed onto a glass pane stacker (not shown) in a predetermined order.

The glass sheets 125(a), (b) are then passed through a furnace, indicated generally by the reference numeral 161 (see Fig.25), for a predetermined period of time in order to temper the glass. The glass sheets 125(a),(b) are then allowed to cool on cooling beds (not shown) prior to onward delivery to a panel forming station, lE050775 _ 14 - indicated generally by the reference numeral 170 (see Fig. 26).

With reference to Fig. 26, there is shown the panel forming station 170, at which station a spacing frame 4 is secured by its rear face to a facing surface of the glass sheet 125(a) so that the peripheral edges of the glass sheet 125(a) project outwardly of the outer peripheral edges of the spacing frame 4. In the instance shown, the spacing frame 4 is secured to a facing surface of the glass sheet 125(a) whilst on the vertical conveyor 102. Both of the glass sheets 125(a),(b) are then delivered one after the other along the vertical conveyor 102 to a gas filled chamber 171, in which gas filled chamber 171 the glass sheet 125(b) is secured to the front face of the spacing frame 4 whilst at the same time a cavity defined between the inner peripheral edges of the spacing frame 4 is filled with an insulating gas present in the gas filled chamber 171. It should be appreciated that the insulating gas is heavier than air and therefore effectively displaces the lighter air out of the cavity.

Fig. 27 shows a sealing station, generally indicated by the reference numeral 180, for applying a seal around a sealant channel formed between the two glass sheets 125(a),(b) and outwardly from the periphery of the spacer frame 4 to form a double glazed glass panel 126.

In the instance shown, the sealing station 180 comprises a sealing arm 181 mounting a seal dispensing head 182, which seal dispensing head 182 moves around the perimeter of the glass sheets 125(a),(b) and discharges a sealant between the glass sheets 125(a),(b) outwardly from the periphery of the spacing frame 4.

Finally, each double glazed glass panel 1 is then removed from the sealing station 180 and stored on a rack 183 for subsequent delivery to a storage facility or to transport vehicles for onward delivery to customers for mounting into doors and/or windows as required or as desired.

Aspects of the present invention have been described by way of example only and it should be appreciated that additions and/or modifications may be made thereto without departing from the scope thereof.

Claims (1)

1. A process for preparing a double glazed glass panel of the type comprising a pair of glass sheets separated by a spacing frame, the process comprising the steps of: (a) cutting a hollow elongate length of material to a desired length, (b) bending the elongate length of material intermediate its ends to form a spacing frame having outwardly directed front and rear faces and outer and inner peripheral edges; (c) joining the free ends of the spacing frame together; (d) drilling a hole through the outer peripheral edges of the spacing frame and injecting a desiccant into the spacing frame through the hole; (e) sealing the hole; (f) applying a butyl seal around the front and rear faces of the spacing frame; (g) delivering the spacing frame to the panel forming station; (h) preparing a pattern of breaks to be made on a base glass sheet; (i) aligning the base glass sheet on a conveyor so that any breaks to be made which extend fully across the base glass sheet perpendicular to the direction of movement of the base glass sheet along the conveyor are performed first; (j) spraying a band of oil on a surface of the base glass sheet corresponding to the pattern of breaks; |EO50775 (k) scoring the base glass sheet along the band of oil to form break lines; (l) breaking the base glass sheet along the scores to fonn a plurality of glass sheets of a desired size, which breaking comprises the steps of: breaking the base glass sheet along all complete transverse break lines to form a plurality of glass sheets, which transverse break lines extend fully across the base glass sheet in a direction perpendicular to the direction of movement of the base glass sheet along the conveyor, the complete transverse break lines are broken by a complete transverse break line breaking machine comprising a transverse break bar which moves up and down through the conveyor between a pair of transverse overhead crossbars which are located proud of the break bar, which break bar moves up to engage the glass sheet in the region of a transverse break line so as to push the base glass sheet up against the transverse overhead crossbars to break the base glass sheet along a specific transverse break line. separating the glass sheets; breaking the glass sheets along any longitudinal break lines, which break lines extend fully along the intermediate glass sheets in the direction of movement of the glass sheets along the conveyor, separating the glass sheets resulting from step(iii), and breaking the glass sheets along any unbroken transverse break lines to form a plurality of glass sheets of a desired size; |EO50775 (m) chamfering the edges of the glass sheets; (n) washing and drying the glass sheets; (0) passing the glass sheets through a furnace for a predetermined period of time to temper the glass sheets; (q) cooling the glass sheets prior to delivery to the panel forming station; (r) at the panel fonning station, securing a spacing frame by its rear face to a facing surface of one of a pair of the glass sheets such that the glass sheet projects outwardly of the outer peripheral edges of the spacing frame; (s) delivering the pair of glass sheets to a gas tilled chamber, in which gas filled chamber a facing surface of the other of the pair of glass sheets is secured to the front face of the spacing frame whilst at the same time a cavity defined between the inner peripheral edges of the spacing frame is filled with an insulating gas present in the gas filled chamber; (t) applying a seal around a sealant channel formed between the two glass panes and outwardly from the periphery of the spacing frame to form a double glazed glass panel. A process as claimed in claim 1, in which the edges of each glass sheet are chamfered by a pair of endless belts, each belt secured around a pair of spaced apart rotatable axles and disposed at an angle relative to one another to form a V-shape having an open mouth facing the edges of the glass sheet so that when the open mouth is pushed against the glass sheet and the belts are rotated by the axles the belts slide against a front and a rear facing edge of the glass sheet at the same time, a process as claimed in claim 2, in which the belts in each pair of belts are positioned one offset forward of the other, the pair of belts being together moveable around the periphery of the glass sheet. IEo5o775 A process as claimed in any preceding claim, in which the pattern of breaks is generated by a computer system running computer software programs, which, computer system in response to input received from computer operators generate the required break patterns. A double glazed glass panel produced according to the process as claimed in any preceding claim. A process for producing double glazed glass panels substantially as herein described with reference to and as illustrated in the accompanying drawings: