Abstract: A spark electrode assembly has an elongate electrode with an inner insulator arranged for operable attachment to a support structure. The inner insulator surrounds the electrode with one end of the electrode positioned adjacent a ground element across a spark gap and another end of the electrode extending relative to the support structure for attachment to a source of electrical power. An outer insulator is spaced radially outwardly from the inner insulator and surrounds the inner insulator generally adjacent the end of the electrode adjacent the ground element. The inner and outer insulators cooperate to inhibit the formation of a continuous lubrication layer thereon, thereby establishing an area generally free from the lubrication layer between the end of the electrode adjacent the ground element and the support structure.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass that includes a spout for delivering core glass from a first source through a first orifice. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through a gap between the first and second orifices. A tube delivers casing glass from the outlet opening of a casing glass spout to the annular chamber in such a way that glass flows by gravity through the orifices from the first and second sources to form the cased glass stream. A hollow tube within the casing glass spout is positioned with respect to the spout outlet opening for metering flow of casing glass through the outlet opening and delivery tube to the annular chamber surrounding the orifices.

Abstract: A burner (16, 116, 216) of a nozzle-mixing type receives a carbonaceous fuel, for example, an acetylene-based fuel, from a fuel line (20) and an oxidant, such as relatively pure oxygen, from an oxidant line (18), the oxidant being supplied to the burner at a rate insufficient to result in complete combustion of the fuel, to thereby produced a sooty flame that is useful in applying lubricating soot particles to a molten glass contacting surface of a glass manufacturing machine. The burner, which is intermittently operated by a solenoid valve (38) in the oxidant line and by a solenoid valve (40) in the fuel line, has a fuel inlet passage (60) that extends along a longitudinal central axis of a tip element (56) of the burner, and an annular inlet passage (64) that surrounds the fuel inlet passage.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass that includes a spout for delivering core glass from a first source through a first orifice. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through a gap between the first and second orifices. A tube delivers casing glass from the outlet opening of a casing glass spout to the annular chamber in such a way that glass flows by gravity through the orifices from the first and second sources to form the cased glass stream. A hollow tube within the casing glass spout is positioned with respect to the spout outlet opening for metering flow of casing glass through the outlet opening and delivery tube to the annular chamber surrounding the orifices.

Abstract: Apparatus for delivering a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first or upper orifice ring having at least one orifice for receiving core glass, and a second or lower orifice ring secured beneath the first orifice ring and having a second orifice aligned with each first orifice. A chamber for receiving casing glass is formed between the first and second orifice rings surrounding the second orifice. A bushing is received in an opening in the second orifice ring to form each second orifice in the second orifice ring. The bushing has a first radially extending flange supported on an upper surface of the second orifice ring and a bushing end spaced upwardly from the first flange for admitting casing glass from the chamber to the second orifice.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass that includes a spout for delivering core glass from a first source through a first orifice. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through a gap between the first and second orifices. A tube delivers casing glass from the outlet opening of a casing glass spout to the annular chamber in such a way that glass flows by gravity through the orifices from the first and second sources to form the cased glass stream. A hollow tube within the casing glass spout is positioned with respect to the spout outlet opening for metering flow of casing glass through the outlet opening and delivery tube to the annular chamber surrounding the orifices.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source, and an orifice ring forming a second orifice vertically spaced beneath and aligned with the first orifice. A chamber surrounds the second orifice and communicates with the second orifice through a metering gap between the first and second orifices. Casing glass is delivered from a second source to the chamber, such that glass flows by gravity from the first and second sources through the orifices to form the cased glass stream. A heater ring of refractory material is disposed beneath the orifice ring, and includes at least one electrical heater embedded in the refractory material of the heater ring. The electrical heater is thus disposed external to the casing glass chamber for adding heat to casing glass flowing through the chamber to the metering gap.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass that includes a spout for delivering core glass from a first source through a first orifice. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through a gap between the first and second orifices. A tube delivers casing glass from the outlet opening of a casing glass spout to the annular chamber in such a way that glass flows by gravity through the orifices from the first and second sources to form the cased glass stream. A hollow tube within the casing glass spout is positioned with respect to the spout outlet opening for metering flow of casing glass through the outlet opening and delivery tube to the annular chamber surrounding the orifices.

Abstract: A method and apparatus for delivering a glass stream comprising a first inner layer and a second outer layer, comprising a generally vertical orifice, and delivering glass from a second source such that the glass from said second source provides an outer layer about the glass from the first source as it flows through said orifice. A resistance heated tube assembly is made of platinum or material having similar resistance heating properties and extends from a glass source to an orifice through which the glass flows from a glass source for the inner layer. The tube assembly includes a tube portion having an inlet end that communicates with the source for the outer layer and an outlet end that communicates with the source. The tube portion has an axis positioned at any angle ranging between the horizontal and vertical but preferably has an axis which is more vertical than horizontal. Flanges are secured to the ends of said tube portion, and the flanges are connected to an electric power supply.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by a chamber that communicates with the second orifice through a gap between the first and second orifices. A spout delivers casing glass from a second source through a tube to the chamber in such a way that glass flows by gravity from the first and second sources through the orifices to form the cased glass stream. Rate of glass flow through the second or casing glass source is measured and compared with one or more preset limits. Rate of casing glass flow from the second source to the chamber surrounding the orifices is adjusted when rate of flow through the second source departs from the preset limit. In this way, a desired ratio of casing glass to core glass is automatically maintained.

Abstract: A method of controlling the flow of glass through multiple orifices in which a plurality of closely spaced vertical plungers have cylindrical lower portions and oval upper portions. The upper portions of the plungers are engaged and supported in closely spaced side-by-side relationship in a clamping mechanism, in which each plunger is individually adjusted independently of the other plungers. The plungers are reciprocated simultaneously for controlling the flow of glass through the orifices.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by a chamber that communicates with the second orifice through a gap between the first and second orifices. A spout delivers casing glass from a second source through a tube to the chamber in such a way that glass flows by gravity from the first and second sources through the orifices to form the cased glass stream. Rate of glass flow through the second or casing glass source is measured and compared with one or more preset limits. Rate of casing glass flow from the second source to the chamber surrounding the orifices is adjusted when rate of flow through the second source departs from the preset limit. In this way, a desired ratio of casing glass to core glass is automatically maintained.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source, and a second orifice vertically spaced beneath and aligned with the first orifice. A chamber surrounds the second orifice and communicates with the second orifice through a metering gap between the first and second orifices. Casing glass is delivered from a second source to one side of the chamber such that glass flows by gravity from both the first and second sources through the orifices to form the cased glass stream.

Abstract: An apparatus for delivering a glass stream including a first inner layer and a second outer layer, including a generally vertical orifice, and delivering glass from a second source such that the glass from said second source provides an outer layer about the glass from the first source as it flows through the orifice. A resistance heated tube assembly is made of platinum or material having similar resistance heating properties and extends from a glass source to an orifice through which the glass flows from a glass source for the inner layer. The tube assembly includes a tube portion having an inlet end that communicates with the source for the outer layer and an outlet end that communicates with the source. The tube portion has an axis positioned at any angle ranging between the horizontal and vertical but preferably has an axis which is more vertical than horizontal. Flanges are secured to the ends of the tube portion, and the flanges are connected to an electric power supply.

Abstract: A method and apparatus for delivering a coated glass stream having a first inner layer and a second outer layer wherein the method comprises providing a vertical orifice, delivering molten glass from a first source through the orifice, providing a gap about the orifice intermediate its upper and lower ends, delivering glass from a second source about the gap such that the glass from the second source flows through the gap to provide an outer layer about the glass from said first source as it flows through the orifice, and controlling the size and shape of the gap parallel to the flow and the size of the gap perpendicular to the flow such that the gap provides sufficient flow resistance and the gap is of sufficient size and shape to prevent clogging.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source, and a second orifice vertically spaced beneath and aligned with the first orifice. A chamber surrounds the second orifice and communicates with the second orifice through a metering gap between the first and second orifices. Casing glass is delivered from a second source to the chamber such that glass flows by gravity through the orifices from the first and second sources to form the cased glass stream. The first and second orifices are disposed in respective first and second orifice rings of refractory composition. The first orifice ring has a peripheral flange and an interior passage for glass flow from the first source to the first orifice.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a first orifice for receiving core glass from a first source. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through the gap between the first and second orifices. A spout delivers casing glass from a second source through a tube to the annular chamber in such a way that glass flows by gravity from the first and second sources through the orifices to form the cased glass stream. A plurality of gas burners are disposed in the spout above the glass pool. The casing glass delivery spout is configured for improved heat transfer to, and improved heat retention within, the casing glass pool within the spout. Specifically, the glass pool surface area is enlarged, and the glass pool depth is reduced.

Abstract: A method for delivering a coated glass stream having a first inner layer and a second outer layer wherein the method includes providing a vertical orifice, delivering molten glass from a first source through the orifice, providing a gap about the orifice intermediate its upper and lower ends, delivering glass from a second source about the gap such that the glass from the second source flows through the gap to provide an outer layer about the glass from the first source as it flows through the orifice, and controlling the size and shape of the gap parallel to the flow and the size of the gap perpendicular to the flow such that the gap provides sufficient flow resistance and the gap is of sufficient size and shape to prevent clogging.

Abstract: A glass delivery system including a first forehearth having an orifice, a second forehearth having an orifice, a bottom pan assembly adapted to be positioned underneath the orifice of the first forehearth, and a glass delivery tube having an upper end adapted to be positioned underneath the orifice of the second forehearth and a lower end adapted to deliver glass to the bottom pan assembly. The orifice is adapted to combine the glass from the two forehearths and, deliver cased glass to provide an interior glass from said first forehearth and an external layer of glass from said second forehearth. Provision is made for moving the glass delivery tube horizontally, vertically and in azimuth relative to the second forehearth and for moving the bottom assembly relative to the first forehearth.

Abstract: Apparatus for forming a cased glass stream that includes at least one pair of aligned orifices coupled to sources of core and casing glass such that glass flows by gravity from the glass sources through the aligned orifices to form a cased glass stream. The orifices are carried by an orifice housing mounted on a frame for movement into seating engagement of the orifice housing against the core and casing glass delivery mechanisms. A fluid manifold is mounted on the orifice housing, with an inlet for connection to a source of cooling fluid such as air. A plurality of outlets on the manifold are directed toward the area of seating engagement between the orifice ring housing and the core and casing glass delivery mechanisms for cooling the seating area and thereby reducing leakage of glass between the housing and the glass delivery mechanisms.