Abstract: A hollow glazing unit comprising vitreous sheets and a plastic foil wherein said vitreous sheets are held in spaced relationship by marginal spacing means which comprise one or more metal strips forming a spacing web located outward of the plastic foil, the metal strips being connected to the vitreous sheets by solder joints, wherein a plastic foil is held taut between and in spaced relationship to the vitreous sheets by means comprising components distinct from the spacing strip.

Abstract: In a method of manufacturing a glazing panel comprising sheets which are joined together along the margin of the panel using heat-activatable bonding medium (e.g. solder) which is electrically conductive and/or in contact with electrically conductive material and which is activated in situ by induction heating, the induction heating is performed using an inductor 65 powered by an aperiodic generator 57 whose power output setting is determined in dependence on the instantaneous resonant frequency of the inductor circuit as influenced by the load.

Abstract: A method of manufacturing a polygonal glazing panel comprising sheets 61, 62 which are joined together along the margin of the panel using heat-activatable bonding medium 66,67 which is electrically conductive and/or in contact with electrically conductive material 63 comprised within the panel and which is activated in situ by induction heating is characterized in that for the induction heating use is made of a polygonal inductor loop each of whose sides 50, 51, 52, 53 and 68 comprises a conductor or conductors of tubular bar or of rod form, the loop being spaced from the work 61 to 67 and so disposed in relation to the margin of the work that the bonding medium 66, 67 is heated simultaneously at all positions along the joint or joints to be formed.

Abstract: A method of soldering a first, vitreous component for example a sheet to at least one second component which is vitreous or metallic, in which the or each vitreous component is metallized in the joint region(s), the components are assembled together in the required relationship where they may be held by a clamp and the joint region(s) of the assembly is or are dipped in a bath of molten solder to bond it together as a unit. Such a unit may be constituted as an envelope containing one or more electrical circuit components, as a fluid flow directing unit or as a pane for incorporation into a leaded window.

Abstract: A method of manufacturing a hermetically sealed envelope comprising assembling envelope-forming components of which at least one is a vitreous wall forming component wherein the or each vitreous component is metallized along a zone where it is to be bonded by solder to form a sealing joint. Such sealing is effected while the assembly 13 of envelope-forming components is within a hermetically sealable chamber 1 e.g. using heating devices 11, 12. The chamber may be evacuated via exhaust port 7 and valve 9 and optionally filled with a gas other than air via inlet port 4 and valve 6.